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Sample records for isolated ventricular noncompaction

  1. Isolated ventricular noncompaction.

    PubMed

    Okçün Baniş; Tekin, Abdullah; Oz, Büge; Küçükoğlu, M Serdar

    2004-04-01

    Isolated ventricular noncompaction of myocardium is a rare congenital disease due to an arrest of myocardial morphogenesis during foetal development. It is characterized by a thin compacted epicardial and an extremely thickened endocardial layer with prominent trabeculations and deep intertrabecular recesses. The persistence of myocardial noncompaction is usually an associated anomaly in patients with congenital left or right ventricular outflow tract obstruction. However, isolated noncompaction of myocardium is not associated with any factors that would explain it apart from the foetal arrest of compaction of the ventricular myocardium. The disease results in systolic and diastolic ventricular dysfunction, systemic embolism and ventricular arrhythmias. We describe a case of isolated noncompaction of the ventricular myocardium in a 20-year-old man who presented initially with ventricular tachycardia.

  2. Isolated right ventricular noncompaction in a newborn.

    PubMed

    Sert, Ahmet; Aypar, Ebru; Aslan, Eyup; Odabas, Dursun

    2013-01-01

    Noncompaction of the ventricular myocardium is a rare cardiomyopathy characterized by a pattern of prominent trabecular meshwork and deep intertrabecular recesses. The prevalence of left ventricular noncompaction is 0.01% in adults and 0.14% in pediatric patients. Although the usual site of involvement is the left ventricle, the right ventricle and septum can be affected as well. Previously, right ventricular noncompaction has been described only in a few cases of newborns with congenital heart defects and in adult patients. This report presents a newborn with isolated right ventricular noncompaction. To the authors' knowledge, this is the first newborn patient with isolated right ventricular noncompaction but no congenital heart defect involving only the right ventricle.

  3. Isolated Ventricular Noncompaction Cardiomyopathy Presenting as Recurrent Syncope

    PubMed Central

    Ladia, Vatsal; Sitwala, Puja; AlBalbissi, Kais

    2016-01-01

    Isolated ventricular noncompaction (IVNC) occurs because of interruption of trabecular morphogenesis in the myocardium leading to ventricular noncompaction. Patients present with heart failure or with systemic complications secondary to thromboembolism or arrhythmias. High index of suspicion is necessary for early diagnosis. We present a case of 48-year-old male with unexplained recurrent syncope who was eventually diagnosed with IVNC. PMID:28105050

  4. [Isolated left ventricular noncompaction causing refractory heart failure].

    PubMed

    Meneguz-Moreno, Rafael Alexandre; Rodrigues da Costa Teixeira, Felipe; Rossi Neto, João Manoel; Finger, Marco Aurélio; Casadei, Carolina; Castillo, Maria Teresa; Sanchez de Almeida, Antonio Flávio

    2016-03-01

    Left ventricular noncompaction is a rare congenital anomaly characterized by excessive left ventricular trabeculation, deep intertrabecular recesses and a thin compacted layer due to the arrest of compaction of myocardial fibers during embryonic development. We report the case of a young patient with isolated left ventricular noncompaction, leading to refractory heart failure that required extracorporeal membrane oxygenation followed by emergency heart transplantation. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  5. Verapamil-sensitive fascicular ventricular tachycardia in a patient with isolated left ventricular noncompaction.

    PubMed

    Ying, Zhi-Qiang; Chen, Miao-Yan

    2014-01-01

    Isolated left ventricular noncompaction (IVNC) is a rare congenital form of cardiomyopathy. Verapamil-sensitive fascicular ventricular tachycardia is a rare arrhythmogenic condition characterized by a right bundle-branch block pattern and left-axis deviation with a relatively narrow QRS complex. We herein present the case of a patient with IVNC who presented with verapamil-sensitive fascicular ventricular tachycardia.

  6. [Acute cerebral ischemia: an unusual clinical presentation of isolated left ventricular noncompaction in an adult patient].

    PubMed

    Fiorencis, Andrea; Quadretti, Laura; Bacich, Daniela; Chiodi, Elisabetta; Mele, Donato; Fiorencis, Roberto

    2013-01-01

    Isolated left ventricular noncompaction in adults is uncommon. The most frequent clinical manifestations are heart failure due to left ventricular systolic dysfunction and supraventricular and ventricular arrhythmias, which may be sustained and associated with sudden death. Thromboembolic complications are also possible. We report the case of an adult patient with isolated left ventricular noncompaction who came to our observation because of acute cerebral ischemia, an initial presentation of the disease only rarely described.

  7. Isolated left ventricular noncompaction diagnosed by transthoracic threedimensional echocardiography.

    PubMed

    Wang, X X; Song, Z Z

    2009-05-01

    A 55-year-old man was admitted to our hospital because of chest distress, associated with activity. Two-dimensional echocardiography (2DE) demonstrated a suspected trabeculation versus false tendon of the left ventricular apex cordis but not meeting the diagnostic criteria of noncompaction of the ventricular myocardium (NVM). Threedimensional echocardiography (3DE) revealed more prominent trabeculations and deeper intertrabecular recesses of the left ventricular apex, which were consistent with the diagnostic criteria of NVM. In contrast to 2DE, 3DE provides wide, pyramid-shaped datasets that encompass the entire left ventricle. (Neth Heart J 2009;17:208-10.).

  8. Anesthetic experience of patient with isolated left ventricular noncompaction: a case report

    PubMed Central

    Kim, Doyeon; Kim, Eunhee; Lee, Jong-Hwan; Lee, Sangmin Maria; Lee, Jung Eun

    2016-01-01

    Isolated left ventricular noncompaction (LVNC) is a rare primary genetic cardiomyopathy characterized by prominent trabeculation of the left ventricular wall and intertrabecular recesses. Perioperative management of the patient with LVNC might be challenging due to the clinical symptoms of heart failure, systemic thromboembolic events, and fatal left ventricular arrhythmias. We conducted real time intraoperative transesophageal echocardiography in a patient with LVNC undergoing general anesthesia for ovarian cystectomy. PMID:27274374

  9. Isolated left ventricular noncompaction in a newborn with Pierre-Robin sequence.

    PubMed

    Aypar, Ebru; Sert, Ahmet; Gokmen, Zeynel; Aslan, Eyup; Odabas, Dursun

    2013-02-01

    Pierre-Robin sequence or syndrome (PRS) (OMIM #261800) is characterized by a small mandible (micrognathia), posterior displacement/retraction of the tongue (glossoptosis), and upper airway obstruction. It has an incidence varying from 1 in 8,500 to 1 in 30,000 births. Congenital heart defects (CHDs) occur in 20 % of the patients with PRS. Ventricular septal defect, patent ductus arteriosus, and atrial septal defects are the most common lesions. Noncompaction of the ventricular myocardium is a rare cardiomyopathy characterized by a pattern of prominent trabecular meshwork and deep intertrabecular recesses. It is thought to be caused by arrest of the normal endomyocardial morphogenesis. Isolated left ventricular noncompaction (LVNC) in patients with PRS has not been reported previously. This report describes a newborn with PRS and isolated LVNC. Previously, LVNC has been reported in association with mitochondrial disorders, Barth syndrome hypertrophic cardiomyopathy, zaspopathy, muscular dystrophy type 1, 1p36 deletion, Turner syndrome, Ohtahara syndrome, distal 5q deletion, mosaic trisomy 22, trisomy 13, DiGeorge syndrome, and 1q43 deletion with decreasing frequency. Karyotype analysis of the reported patient showed normal chromosomes (46, XX), and a fluorescent in situ hybridization study did not show chromosome 22q11.2 deletion. This is the first clinical report of a patient with isolated LVNC and PRS. Noncompaction of the ventricular myocardium is a rare and unique disorder with characteristic morphologic features that can be identified by echocardiography. Long-term follow-up evaluation for development of progressive LV dysfunction and cardiac arrhythmias is indicated for these patients.

  10. Examination of isolated ventricular noncompaction (hypertrabeculation) as a distinct entity in adults.

    PubMed

    Roberts, William Clifford; Karia, Sumit Jagdish; Ko, Jong Mi; Grayburn, Paul Arthur; George, Betsy Ann; Hall, Shelley Anne; Kuiper, Johannes Jacob; Meyer, Dan Marshall

    2011-09-01

    Three patients (2 women) 36, 45, and 49 years of age underwent cardiac transplantation for what was diagnosed clinically as nonischemic dilated cardiomyopathy. Examination of the transthoracic echocardiogram and explanted heart in each disclosed marked hypertrabeculation involving the free wall of the very dilated left ventricle, a finding consistent with what has been termed "isolated ventricular noncompaction" (IVNC). Although these 3 cases anatomically fulfilled the echocardiographic definition of IVNC, review of previous publications containing gross photographs of the heart suggests that IVNC is overdiagnosed at least morphologically. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Lown-Ganong-Levine syndrome in a 3-month-old infant with isolated left ventricular noncompaction.

    PubMed

    Shabanian, Reza; Kiani, Abdolrazagh; Rad, Elaheh Malakan; Eslamiyeh, Hosein

    2010-02-01

    This report describes a 3-month-old boy with isolated left ventricular noncompaction admitted to a medical facility due to heart failure and dysrhythmia. His electrocardiogram showed a short PR interval and a normal QRS complex after abortion of supraventricular tachycardia in favor of Lown-Ganong-Levine syndrome or enhanced atrioventricular nodal conduction.

  12. Echocardiographic and pathoanatomical characteristics of isolated left ventricular non-compaction: a step towards classification as a distinct cardiomyopathy

    PubMed Central

    Jenni, R; Oechslin, E; Schneider, J; Jost, C; Kaufmann, P

    2001-01-01

    AIM—To determine clear cut echocardiographic criteria for isolated ventricular non-compaction (IVNC), a cardiomyopathy as yet "unclassified" by the World Health Organization. The disease is not widely known and its diagnosis mostly missed.
METHODS AND RESULTS—In seven out of a series of 34 patients with IVNC the in vivo echocardiographic characteristics were validated against the anatomical examination of the heart removed after death in four and due to heart transplantation in three patients. Four morphological criteria diagnostic for IVNC were found. (1) Coexisting cardiac abnormalities were absent (by definition). (2) A two layer structure was seen, with a compacted thin epicardial band and a much thicker non-compacted endocardial layer of trabecular meshwork with deep endomyocardial spaces. A maximal end systolic ratio of non-compacted to compacted layers of > 2 is diagnostic. (3) The predominant localisation of the pathology was to mid-lateral (seven of seven patients), apical (six), and mid-inferior (seven) areas. The pathological preparations confirmed the echocardiographic findings. Concomitant regional hypokinesia was not confined to the non-compacted segments. (4) There was colour Doppler evidence of deep perfused intertrabecular recesses.
CONCLUSIONS—Four clear cut echocardiographic diagnostic criteria were established. It is suggested that the WHO classification of cardiomyopathies be reconsidered to include IVNC as a distinct cardiomyopathy.


Keywords: isolated ventricular non-compaction; morphological criteria; cardiomyopathy; echocardiography; pathology PMID:11711464

  13. Case report. Isolated left ventricular myocardium non-compaction: MR imaging findings from three cases.

    PubMed

    Junqueira, F P; Fernandes, F D B; Coutinho, A C; De Pontes, P V; Domingues, R C

    2009-02-01

    The purpose of this study is to report three cases of left ventricular myocardium non-compaction (LVNC), with emphasis on the MRI findings. From May 2006 to February 2007, three patients -- 2 females (6 years and 42 years of age) and 1 male (18 years of age) -- presented to our radiology department, two of them with fatigue, shortness of breath and episodes of syncope and arrhythmia, for further investigation by cardiac MRI because an apparent asymmetrical pattern of hypertrophy of the left ventricular myocardium was suspected by transthoracic echocardiography. The 18-year-old patient was only experiencing arrhythmia, and arrhythmogenic right ventricular dysplasia was suspected. The images (produced by a 1.5T MRI system) were interpreted by two experienced radiologists and post-processed with Argus software (Siemens, Germany) for ejection fraction calculation. In all three patients, MRI aided in the correct identification of prominent ventricular myocardial trabeculations and deep intertrabecular recesses communicating with the ventricular cavity, as well as areas of hypokinesia with depressed systolic function, and showed the absence of myocardial delayed enhancement and other structural heart defects. In conclusion, cardiac MRI was useful for correctly identifying this rare congenital heart disorder and appears to increase diagnostic accuracy. Although considered a rare anomaly, radiologists should be capable of recognizing LVNC, as current non-invasive imaging methods have increased the frequency of this diagnosis and timely detection is vital in considering early-stage transplantation.

  14. [Heart transplantation for the treatment of isolated left ventricular myocardial noncompaction. First case in Mexico].

    PubMed

    Zetina-Tun, Hugo Jesús; Careaga-Reyna, Guillermo; Galván-Díaz, José; Sánchez-Uribe, Magdalena

    2016-10-20

    Myocardial noncompaction of the left ventricle is a congenital cardiomyopathy characterised by left ventricular hypertrabeculation and prominent intertrabecular recesses. The incidence ranges from 0.15% to 2.2%. Clinical manifestations include heart failure, arrhythmias, and stroke. Prognosis is fatal in most cases. Heart transplantation is a therapeutic option for this cardiomyopathy, and few had been made worldwide. The case is presented of a 20 year-old male with noncompacted myocardium of the left ventricle, who had clinical signs of heart failure. His functional class was IV on the New York Heart Association scale. He was successfully transplanted. Its survival to 15 months is optimal in class I New York Heart Association, and endomyocardial biopsies have been reported without evidence of acute rejection. It is concluded that heart transplantation modified the natural history and improved survival in patients with this congenital heart disease. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  15. Left ventricular noncompaction diagnosed following Graves' disease

    PubMed Central

    Habib, Habib; Hawatmeh, Amer; Rampal, Upamanyu; Shamoon, Fayez

    2016-01-01

    Isolated left ventricular noncompaction (LVNC) is a rare genetic cardiomyopathy. Clinical manifestations are variable; patients may present with heart failure symptoms, arrhythmias, and systemic thromboembolism. However, it can also be asymptomatic. When asymptomatic, LVNC can manifest later in life after the onset of another unrelated condition. We report a case of LVNC which was diagnosed following a hyperthyroid state secondary to Graves' disease. The association of LVNC with other noncardiac abnormalities including neurological, hematological, and endocrine abnormalities including hypothyroidism has been described in isolated case reports before. To the best of our knowledge, this is the first reported case of LVNC diagnosed following exacerbation in contractile dysfunction triggered by Graves' disease. PMID:27843800

  16. Left ventricular noncompaction cardiomyopathy: updated review.

    PubMed

    Udeoji, Dioma U; Philip, Kiran J; Morrissey, Ryan P; Phan, Anita; Schwarz, Ernst R

    2013-10-01

    The first case of noncompaction was described in 1932 after an autopsy performed on a newborn infant with aortic atresia/coronary-ventricular fistula. Isolated noncompaction cardiomyopathy was first described in 1984. A review on selected/relevant medical literature was conducted using Pubmed from 1984 to 2013 and the pathogenesis, clinical features, and management are discussed. Left ventricular noncompaction (LVNC) is a relatively rare congenital condition that results from arrest of the normal compaction process of the myocardium during fetal development. LVNC shows variability in its genetic pattern, pathophysiologic findings, and clinical presentations. The genetic heterogeneity, phenotypical overlap, and variety in clinical presentation raised the suspicion that LVNC might just be a morphological variant of other cardiomyopathies, but the American Heart Association classifies LVNC as a primary genetic cardiomyopathy. The familiar type is common and follows a X-linked, autosomal-dominant, or mitochondrial-inheritance pattern (in children). LVNC can occur in isolation or coexist with other cardiac and/or systemic anomalies. The clinical presentations are variable ranging from asymptomatic patients to patients who develop ventricular arrhythmias, thromboembolism, heart failure, and sudden cardiac death. Increased awareness over the last 25 years and improvements in technology have increased the identification of this illness and improved the clinical outcome and prognosis. LVNC is commonly diagnosed by echocardiography. Other useful diagnostic techniques for LVNC include cardiac magnetic resonance imaging, computerized tomography, and left ventriculography. Management is symptom based and patients with symptoms have a poorer prognosis. LVNC is a genetically heterogeneous disorder which can be associated with other anomalies. Making the correct diagnosis is important because of the possible associations and the need for long-term management and screening of

  17. A rare case of isolated left ventricular non-compaction. Importance of image technology and disease awareness for a correct diagnosis.

    PubMed

    Mariotti, Egidio; Pierantozzi, Attilio; Bocconcelli, Paolo

    2006-07-01

    In 1999 a 50-year-old man with sustained monomorphic ventricular tachycardia came to our institution for investigation using fundamental echocardiographic imaging. A diagnosis of hypertrophic cardiomyopathy with dilatation and apical thrombus was made. In 2003, a new echocardiographic machine equipped with second harmonic imaging modality became available and after a second investigation the diagnosis was changed to isolated left ventricular non-compaction. The echocardiogram showed hypertrabeculations involving not only the mid-septum but also the basal septum (anterior and posterior) and a thin epicardial layer without the thickened endocardial component.

  18. Left ventricular noncompaction: A rare indication for pediatric heart transplantation.

    PubMed

    Magalhães, Mariana; Costa, Patrícia; Vaz, Maria Teresa; Pinheiro Torres, José; Areias, José Carlos

    2016-01-01

    Isolated left ventricular noncompaction is a rare congenital cardiomyopathy, characterized morphologically by a dilated left ventricle, prominent trabeculations and deep intertrabecular recesses in the ventricular myocardium, with no other structural heart disease. It is thought to be secondary to an arrest of normal myocardial compaction during fetal life. Clinically, the disease presents with heart failure, embolic events, arrhythmias or sudden death. Current diagnostic criteria are based on clinical and imaging data and two-dimensional and color Doppler echocardiography is the first-line exam. There is no specific therapy and treatment is aimed at associated comorbidities. Cases refractory to medical therapy may require heart transplantation. The authors describe a case of severe and refractory heart failure, which was the initial presentation of isolated left ventricular noncompaction in a previously healthy male child, who underwent successful heart transplantation. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  19. Left Ventricular Noncompaction Cardiomyopathy Presenting with Heart Failure in a 35-Year-Old Man.

    PubMed

    Papadopoulos, Kyriacos; Petrou, Petros M; Michaelides, Demos

    2017-08-01

    Isolated ventricular noncompaction, a rare genetic cardiomyopathy, is thought to be caused by the arrest of normal myocardial morphogenesis. It is characterized by prominent, excessive trabeculation in a ventricular wall segment and deep intertrabecular recesses perfused from the ventricular cavity. The condition can present with heart failure, systematic embolic events, and ventricular arrhythmias. Two-dimensional echocardiography is the typical diagnostic method. We report a case of heart failure in a 35-year-old man who presented with palpitations. Two-dimensional echocardiograms revealed left ventricular noncompaction, which markedly improved after standard heart failure therapy.

  20. The Current Approach to Diagnosis and Management of Left Ventricular Noncompaction Cardiomyopathy: Review of the Literature

    PubMed Central

    Bennett, Courtney E.; Freudenberger, Ronald

    2016-01-01

    Isolated left ventricular noncompaction (LVNC) is a genetic cardiomyopathy characterized by prominent ventricular trabeculations and deep intertrabecular recesses, or sinusoids, in communication with the left ventricular cavity. The low prevalence of patients with this cardiomyopathy presents a unique challenge for large, prospective trials to assess its pathogenesis, management, and outcomes. In this paper we review the embryology and genetics of LVNC, the diagnostic approach, and propose a management approach based on the current literature available. PMID:26881173

  1. Left ventricular non-compaction in a patient with ankylosing

    PubMed Central

    Toufan, Mehrnoush; Pourafkari, Leili; Nader, Nader D.

    2016-01-01

    A 58 years old male with a long-standing history of HLA-B27 positive ankylosing spondylitis presented with increasing fatigue and dyspnea on exertion. He had left ventricular dysfunction and enlargement, flail right coronary leaflet of aortic valve with severe eccentric aortic insufficiency along with left ventricular non-compaction in echocardiography. The most common cardiac manifestations of ankylosing spondylitis are aortic insufficiency and conduction disturbances. Involvement of myocardium, in the form of dilated cardiomyopathy and restrictive cardiomyopathy, has also been reported. This case presents a very rare association of ankylosing spondylitis with non-compaction cardiomyopathy. PMID:28210476

  2. Right atrial deformation analysis in isolated left ventricular noncompaction - insights from the three-dimensional speckle tracking echocardiographic MAGYAR-Path Study.

    PubMed

    Nemes, Attila; Domsik, Péter; Kalapos, Anita; Gavallér, Henriette; Oszlánczi, Mónika; Forster, Tamás

    2016-10-01

    Isolated left ventricular noncompaction (ILVNC) is a rare cardiomyopathy characterized by a prominent trabecular meshwork and deep intertrabecular recesses. The present study aimed to examine right atrial (RA) volumes, volume-based functional properties and strains by three-dimensional speckle-tracking echocardiography (3DSTE) in ILVNC patients. The study group consisted of 13 patients with ILVNC (mean age: 54.6±14.1 years, six male) and 23 healthy age- and gender-matched volunteers (mean age: 50.4±12.4 years, 10 male), who served as normal controls. Complete two-dimensional Doppler echocardiography and 3DSTE were performed in all cases. Increased systolic maximum (58.2±15.3 ml vs. 40.5±11.8 ml, p=0.0004) and diastolic pre-atrial contraction (39.6±16.1 ml vs. 28.2±9.2 ml, p=0.01) and minimum (46.2±17.5 ml vs. 34.6±11.6 ml, p=0.02) RA volumes were detected in ILVNC patients. Only total (18.6±8.5 ml vs. 12.2±5.9 ml, p=0.01) and passive (12.0±13.3 vs. 5.9±3.7 ml, p=0.05) RA stroke volumes, representing features of RA reservoir and conduit phases, were increased in ILVNC; active RA stroke volume and all emptying fractions did not differ between ILVNC patients and matched controls. Moreover, global, mean segmental and regional peak strains and strains at atrial contraction showed no differences between ILVNC patients and controls. 3DSTE-derived volumetric analysis confirmed increased cyclic RA volumes in ILVNC. Only mild RA functional alterations were demonstrated in ILVNC. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Postoperative normalization of left ventricular noncompaction and new echocardiographic signs in aorta to left ventricular tunnel.

    PubMed

    Malakan Rad, Elaheh; Zeinaloo, Ali Akbar

    2013-04-01

    We report postoperative normalization of left ventricular noncompaction in a neonate undergoing successful neonatal surgery for type II aorta to left ventricular tunnel (ALVT) associated with a large patent ductus arteriosus, floppy and extremely redundant anterior mitral leaflet, right coronary artery arising directly from the tunnel, and severe left ventricular noncompaction. We also described 2 novel echocardiographic findings in ALVT including "triple wavy line sign" on M-mode echocardiography which disappeared 1 month after operation and "abnormally increased left ventricular posterior wall motion" on M-mode of standard parasternal long-axis view on color tissue Doppler imaging (TDI) that also normalized postoperatively. We showed that proper definition of endocardial border is extremely important in strain and strain rate imaging in the context of left ventricular noncompaction. Preoperative longitudinal strain and strain rate were significantly decreased in comparison to radial strain and strain rate. Circumferential strain and strain rate were normal. © 2013, Wiley Periodicals, Inc.

  4. Ebstein's Anomaly, Left Ventricular Noncompaction, and Sudden Cardiac Death

    PubMed Central

    McGee, Michael; Warner, Luke; Collins, Nicholas

    2015-01-01

    Ebstein's anomaly is a congenital disorder characterized by apical displacement of the septal leaflet of the tricuspid valve. Ebstein's anomaly may be seen in association with other cardiac conditions, including patent foramen ovale, atrial septal defect, and left ventricular noncompaction (LVNC). LVNC is characterized by increased trabeculation within the left ventricular apex. Echocardiography is often used to diagnose LVNC; however, magnetic resonance (MR) imaging offers superior characterization of the myocardium. We report a case of sudden cardiac death in a patient with Ebstein's anomaly with unrecognized LVNC noted on post mortem examination with screening documenting the presence of LVNC in one of the patient's twin sons. PMID:26240764

  5. A rare cause of heart failure treated by heart transplantation: noncompaction of the ventricular myocardium.

    PubMed

    Bordes, Julien; Jop, Bertrand; Imbert, Sandrine; Hraiech, Sami; Collard, Frédéric; Kerbaul, François

    2009-01-01

    Noncompaction of the ventricular myocardium is a rare cardiomyopathy due to an arrest of myocardial morphogenesis. The characteristic echocardiographic findings are prominent myocardial trabeculations and deep intertrabecular spaces communicating with the left ventricular cavity. The clinical manifestations include heart failure (HF) signs, ventricular arrhythmias, and cardioembolic events. We describe an illustrative case of noncompaction of the ventricular myocardium associated with bicuspid aortic valve, a 42-year-old male presenting a refractory acute heart failure successfully treated by emergency heart transplantation.

  6. Left ventricular noncompaction cardiomyopathy in end-stage heart failure patients undergoing orthotopic heart transplantation.

    PubMed

    Ottaviani, Giulia; Segura, Ana Maria; Rajapreyar, Indranee N; Zhao, Bihong; Radovancevic, Rajko; Loyalka, Pranav; Kar, Biswajit; Gregoric, Igor; Buja, L Maximilian

    2016-01-01

    Previous studies reported that left ventricular noncompaction (LVNC) is a cardiomyopathy, familial or sporadic, arising from arrest of the normal process of trabecular remodeling during embryonic development. The diagnosis is usually made by echocardiography, but to date, there has been little research on the occurrence and clinicopathological features of LVNC in the explanted hearts of orthotopic heart transplant (OHT) recipients. The clinical, echocardiographic, and pathologic findings were reviewed for evidence of LVNC, diagnosed by echocardiographic criteria, in 105 patients with end-stage heart failure (HF) undergoing OHT. Analyses of multiple sections of the explanted hearts were carried out. The hearts were evaluated for grades (0, negative; 1, mild/occasional foci; 2, moderate/multiple foci; 3, severe/extensive, diffuse) of fibrosis, reactive and replacement, hypertrophy, myocytolysis in left ventricle, right ventricle, interventricular septum, and atria. Absolute measurements of noncompacted and compacted portions of the left ventricle wall and noncompacted/compacted ratios were calculated. Isolated LVNC was observed in 0 of 54 ischemic cardiomyopathy and in 4 of 51 (7.8%) nonischemic cardiomyopathy patients - 2 men and 2 women, with a mean age±SEM of 34.2±6.9years. The echocardiogram disclosed marked left ventricular dilatation, prominent trabeculations, and left ventricle ejection fraction <20%. Mural thrombi were seen in 3 of 4 (75%) patients. The heart weight mean±SEM was 468±55.3 g (range, 340-600g); noncompacted myocardium was 22±5.8mm, compacted myocardium was 13.2±3.5mm, and noncompacted/compacted ratio was 1.7/1±0.2. The total scores of hypetrophy, myocytolysis, and fibrosis were as follows: left ventricle, 7.7±0.2; right ventricle, 6.2±0.5; interventricular septum, 6.7±0.2; and atria, 7.5±0.3. LVNC is an unusual form of nonischemic cardiomyopathy in patients suffering from end-stage HF undergoing OHT. The variability in the

  7. Transesophageal echocardiography monitoring in the delivery of a preeclamptic parturient with severe left ventricular noncompaction.

    PubMed

    Ashford, Eric J; Klimkina, Oksana; Hassan, Zaki-Udin; Colclough, George; Fragneto, Regina

    2014-09-01

    A multidisciplinary approach to the preterm delivery of a preeclamptic parturient with severe left ventricular (LV) noncompaction and pulmonary hypertension using transesophageal echocardiography (TEE) as a monitor of hemodynamic status in lieu of a pulmonary artery catheter during general anesthesia for Cesarean section is presented. This case adds to the available literature on LV noncompaction with pulmonary hypertension in preeclamptic parturients, and addresses the anesthetic concerns and approaches to management using echocardiography in these highly complex patients.

  8. Congenital left ventricular aneurysm coexisting with left ventricular non-compaction in a newborn.

    PubMed

    Ootani, Katsuki; Shimada, Jun; Kitagawa, Yosuke; Konno, Yuki; Miura, Fumitake; Takahashi, Toru; Ito, Etsuro; Ichinose, Kouta; Yonesaka, Susumu

    2014-10-01

    Described herein is the case of a rare combination of congenital left ventricular (LV) aneurysm and left ventricular non-compaction (LVNC) in a newborn. The patient developed refractory heart failure soon after birth and died at 5 months of age. The etiology of both congenital LV aneurysm and LVNC seems to be maldevelopment of the ventricular myocardium during early fetal life. Treatment should be individually tailored depending on clinical severity, and treatment options are limited. Given that this combination of congenital LV aneurysm and LVNC is significantly associated with poor prognosis, it appears that patients with congenital LV aneurysm and LVNC are candidates for early, aggressive intervention, including surgical aneurysmectomy and evaluation for transplantation. It is important to be aware of this combination of congenital LV aneurysm and LVNC, and to make earlier decisions on therapeutic strategy.

  9. Congenital heart surgery in patients with ventricular noncompaction.

    PubMed

    Yu, Wen-zhou; Wang, Ying; Zheng, Jian-wei; Zou, Chengwei

    2015-02-01

    Noncompaction of the ventricular myocardium (NVM) is exceedingly rare and associated with a high morbidity and mortality. This pathology has been associated with other congenital heart diseases (CHDs). The efficacy of surgical treatment of patients with NVM and other CHDs is largely unknown. The aim of the present study was to describe surgical outcomes of 16 patients. Between April 2009 and October 2011, 16 patients with NVM and CHD were admitted to our hospital. Through a clinical chart review, we analyzed results of surgical treatment of NVM with other CHDs retrospectively. The median age was 3.9 years (range 2 m-11 y). The follow-up time was 23.93 months (range 3 m-36 m). Two patients (12.5%) died after the surgery, the remaining patients (87.5%) had an uneventful postoperative course. An additional patient died due to sudden death three months after surgery. Two patients developed recurrent heart failure after surgery. Congestive heart failure, severe arrhythmias, and the range of NVM may be risk factors for death. At 6 months after the operation, the NYHA functional class was significantly improved (2.38 ± 0.89 vs. 1.62 ± 0.65, p = 0.009). The cardiothoracic ratio was significantly reduced when compared to before the operation (p < 0.001). Surgery in patients with NVM and other CHDs can be effective in relieving heart failure, improving heart function, and decreasing heart size. © 2014 Wiley Periodicals, Inc.

  10. Disappearance of left ventricular hypertrabeculation/noncompaction and sudden death in a patient with Turner mosaic syndrome.

    PubMed

    Altenberger, Johann; Hasenauer, Georg; Granitz, Marcel; Stöllberger, Claudia; Finsterer, Josef

    2012-07-15

    Left ventricular hypertrabeculation/noncompaction is associated with various neuromuscular and other rare genetic disorders. In a 53-year-old man with a Turner mosaic karyotype, regression of left ventricular hypertrabeculation/noncompaction was documented by cardiac magnetic resonance imaging and echocardiography after 7 years. During that time, coronary 3-vessel disease and severe left ventricular dys function developed, necessitating coronary bypass surgery. Postoperatively, left ventricular systolic function recovered to an ejection fraction of 40%. The patient died suddenly 6 months postoperatively. In conclusion, the disappearance of left ventricular hypertrabeculation/noncompaction was most likely due to scar formation.

  11. Troponin and Anti-Troponin Autoantibody Levels in Patients with Ventricular Noncompaction

    PubMed Central

    Erer, Hatice Betül; Güvenç, Tolga Sinan; Kemik, Ahu Sarbay; Yılmaz, Hale Yaka; Kul, Şeref; Altay, Servet; Sayar, Nurten; Kaya, Yüksel; Eren, Mehmet

    2013-01-01

    Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24) and noncompaction with reduced EF (LVEF <35%, n = 26) groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group), troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group) and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group) levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG). Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients. PMID:23469039

  12. Troponin and anti-troponin autoantibody levels in patients with ventricular noncompaction.

    PubMed

    Erer, Hatice Betül; Güvenç, Tolga Sinan; Kemik, Ahu Sarbay; Yılmaz, Hale Yaka; Kul, Şeref; Altay, Servet; Sayar, Nurten; Kaya, Yüksel; Eren, Mehmet

    2013-01-01

    Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24) and noncompaction with reduced EF (LVEF <35%, n = 26) groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group), troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group) and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group) levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG). Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients.

  13. Surgery for congenital aortic stenosis in children with left ventricular noncompaction.

    PubMed

    Wang, Chao; Miao, Qi; Liu, Xingrong; Li, Xiaofeng

    2013-07-01

    Left ventricular noncompaction (LVNC) is an uncommon genetic disorder of endocardial morphogenesis, which carries a high mortality from heart failure or sudden cardiac death. This condition is often first diagnosed in adults, but it has also been described in children with other cardiac anomalies. We discuss the management of a 10-year-old female with congenital aortic stenosis associated with LVNC.

  14. Purkinje fiber dysplasia (histiocytoid cardiomyopathy) with ventricular noncompaction in a savannah kitten.

    PubMed

    Gelberg, H B

    2009-07-01

    In a 2-month-old female savannah kitten that died unexpectedly, the pathologic findings of significance were restricted to the heart and included abnormal Purkinje fibers and biventricular myocardial trabeculation or noncompaction. The Purkinje fibers were large, angular, and tightly packed. They contained few disorganized myofibrils among a rarified cytoplasm. The fibers were distinct from adjacent myocytes and were immunohistochemically positive for desmin, muscle actin, myoglobin, sarcomeric actin, and chromogranin A. These findings are identical to those that occur in children with histiocytoid cardiomyopathy, a fatal genetic mitochondrial disorder of Purkinje fibers. Ventricular noncompaction likely has a multifactoral cause that results from fetal arrest of ventricular organizational development that might occur in conjunction with, or independent of, histiocytoid cardiomyopathy.

  15. Left ventricular non-noncompaction: the mitral valve prolapse of the 21st century?

    PubMed

    Captur, Gabriella; Flett, Andrew S; Jacoby, Daniel L; Moon, James C

    2013-03-20

    A spongiform epidemic is upon us - myocardial trabeculae are everywhere as left ventricular noncompaction (LVNC) ingratiates itself into modern day cardiology. Current understanding of the condition is evolving but remains incomplete, and brings to mind the chronicles of another great cardiac story: mitral valve prolapse. Anecdote suggests that many individuals with prominent trabeculae may be being falsely labelled with a disease - LVNC - using poor echocardiographic and cardiovascular magnetic resonance criteria. Until we have robust diagnostic criteria, aetiology, clinicopathological significance and prognosis, the risk of casualties from ascertainment bias will remain. We should look to history and learn from past mistakes - specifically from the mitral valve prolapse story to show the way forward for LVNC. Meanwhile, clinicians (and patients) should be wary, bearing in mind the possibility that they might be seeing LVNNC - left ventricular non-noncompaction.

  16. Left Ventricular Noncompaction Combined With Epinephrine-Secreted Pheochromocytoma Inducing Heart Failure.

    PubMed

    Han, Ling; Luo, Jing-Gang; Chen, Xin; Hu, Wen-Ze; Chen, Li-Wei; Xin, Xiao-Ming; Yang, Ming; Duan, Jun; Zou, Feng-Jun; Teng, Xu; Qi, Yong-Fen

    2016-01-01

    Pheochromocytomas and left ventricular noncompaction (LVNC) are both rare diseases. In this patient, the long duration of the catecholamine-secreted pheochromocytoma caused myocardial ischemia, pressure overload, and hypertrophy, resulting in the onset of heart failure (HF). The LVNC might be associated with the acute attack of HF induced by the pheochromocytoma. This is the first case reporting LVNC in combination with HF secondary to pheochromocytoma.

  17. Neonatal, lethal noncompaction of the left ventricular myocardium is allelic with Barth syndrome.

    PubMed Central

    Bleyl, S B; Mumford, B R; Thompson, V; Carey, J C; Pysher, T J; Chin, T K; Ward, K

    1997-01-01

    Loss-of-function mutations in the G4.5 gene have been shown to cause Barth syndrome (BTHS), an X-linked disorder characterized by cardiac and skeletal myopathy, short stature, and neutropenia. We recently reported a family with a severe X-linked cardiomyopathy described as isolated noncompaction of the left ventricular myocardium (INVM). Other findings associated with BTHS (skeletal myopathy, neutropenia, growth retardation, elevated urinary organic acids, and mitochondrial abnormalities) were either absent or inconsistent. A linkage study of the X chromosome localized INVM to the Xq28 region near the BTHS locus, suggesting that these disorders are allelic. We screened the G4.5 gene for mutations in this family with SSCP and direct sequencing and found a novel glycine-to-arginine substitution at position 197. This position is conserved in a homologous Caenorhabditis elegans protein. We conclude that INVM is a severe allelic variant of BTHS with a specific effect on the heart. This finding provides further structure-function information about the G4.5 gene product and has implications for unexplained cases of severe infantile hypertrophic cardiomyopathy in males. Images Figure 2 PMID:9382097

  18. Ebstein anomaly associated with left ventricular noncompaction: an autosomal dominant condition that can be caused by mutations in MYH7.

    PubMed

    Vermeer, Alexa M C; van Engelen, Klaartje; Postma, Alex V; Baars, Marieke J H; Christiaans, Imke; De Haij, Simone; Klaassen, Sabine; Mulder, Barbara J M; Keavney, Bernard

    2013-08-01

    Left ventricular noncompaction (LVNC) is a relatively common genetic cardiomyopathy, characterized by prominent trabeculations with deep intertrabecular recesses in mainly the left ventricle. Although LVNC often occurs in an isolated entity, it may also be present in various types of congenital heart disease (CHD). The most prevalent CHD in LVNC is Ebstein anomaly, which is a rare form of CHD characterized by apical displacement and partial fusion of the septal and posterior leaflet of the tricuspid valve with the ventricular septum. Several reports of sporadic as well as familial cases of Ebstein anomaly associated with LVNC have been reported. Recent studies identified mutations in the MYH7 gene, encoding the sarcomeric β-myosin heavy chain protein, in patients harboring this specific phenotype. Here, we will review the association between Ebstein anomaly, LVNC and mutations in MYH7, which seems to represent a subtype of Ebstein anomaly with autosomal dominant inheritance and variable penetrance.

  19. Left ventricular non-compaction cardiomyopathy associated with epidermolysis bullosa simplex with muscular dystrophy and PLEC1 mutation.

    PubMed

    Villa, Chet R; Ryan, Thomas D; Collins, James J; Taylor, Michael D; Lucky, Anne W; Jefferies, John L

    2015-02-01

    Plectin mutations have been reported in epidermolysis bullosa simplex with muscular dystrophy. We report the first case of left ventricular non-compaction in an 18-year-old male with epidermolysis bullosa simplex with muscular dystrophy. The patient was diagnosed with epidermolysis bullosa simplex after blistering was noted at birth. Motor function difficulties were first recognized at age 11, however the patient was lost to follow up. He was re-evaluated at age 17 and demonstrated significant ptosis, ophthalmoparesis, and pharyngeal muscle weakness. He had predominant proximal muscle weakness with the inability to raise arms against gravity. He was ambulatory for short distances but lost the ability to rise from the floor at 14 years. He was subsequently diagnosed with epidermyolysis bullosa simplex with muscular dystrophy and a PLEC1 mutation. Screening cardiovascular imaging revealed a diagnosis of isolated left ventricular non-compaction. This case highlights the potential for delayed onset muscular dystrophy in patients with epidermolysis bullosa simplex. Furthermore, this case also underscores the importance of long term, routine cardiac evaluation, including imaging and electrophysiologic evaluation, in patients with epidermolysis bullosa simplex with muscular dystrophy as the cardiac phenotype appears to parallel the variable severity and age of onset that characterize the neuromuscular phenotype. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. [Non-compaction cardiomyopathy].

    PubMed

    Wieneke, Heinrich; Neumann, Till; Breuckmann, Frank; Hunold, Peter; Fries, Jochen W U; Dirsch, Olaf; Erbel, Raimund

    2005-09-01

    Isolated non-compaction of the ventricular myocardium (INVM), also known as left ventricular hypertrabeculation or spongy myocardium, belongs to the "unclassified" cardiomyopathies according to the World Health Organization. The main characteristic of this entity is a prominent trabeculation of the left ventricle with deep intertrabecular recesses communicating with the ventricular cavity. The pathomechanism of INVM is thought to be an arrest in cardiac myogenesis with persistence of embryonic myocardial morphology. The most frequent clinical manifestations include congestive heart failure, ventricular arrhythmias and systemic thromboembolic events. The therapy of INVM comprises standard medical therapy for heart failure.

  1. Histopathological evidence of Fabry disease in a female patient with left ventricular noncompaction.

    PubMed

    Martins, Elisabete; Pinho, Teresa; Carpenter, Stirling; Leite, Sérgio; Garcia, Raquel; Madureira, António; Oliveira, João Paulo

    2014-09-01

    Fabry disease is a rare X-linked lysosomal storage disorder caused by mutations in the alpha-galactosidase gene. The most frequent cardiac presentation of Fabry disease is cardiomyopathy characterized by left ventricular (LV) hypertrophy, usually concentric. Heart disease in affected females tends to be clinically recognized later than in males and cardiac complications are the most frequently reported cause of death in females with Fabry disease. There are few data regarding the association between Fabry disease and LV noncompaction. We report a case of a 30-year-old asymptomatic woman, heterozygous for a nonsense alpha-galactosidase gene mutation (p.R220X), who presented LV noncompaction on cardiac magnetic resonance imaging, without LV wall hypertrophy. Histopathological examination of myocardial fragments showed marked deposition of glycosphingolipids in cardiomyocytes, confirming the diagnosis of Fabry cardiomyopathy. Based on this finding, the patient was proposed for enzyme replacement therapy. This case illustrates the role of endomyocardial biopsy in the clarification of doubtful or atypical findings related to cardiac Fabry disease, even in heterozygous women, and corroborates the contention that Fabry disease should be included in the differential diagnosis of LV hypertrabeculation/noncompaction.

  2. Challenging mitral valve repair for double-orifice mitral valve with noncompaction of left ventricular myocardium.

    PubMed

    Yamasaki, Manabu; Misumi, Hiroyasu; Abe, Kohei; Kawazoe, Kohei

    2017-02-25

    Double-orifice mitral valve (DOMV) is a relatively rare cardiac anomaly. Although usually associated with various cardiac anomalies, co-presence of DOMV and noncompaction of left ventricular myocardium (NCLVM) is extremely rare. Here, we present a 24-year-old male who underwent mitral valve repair using artificial chordae and annuloplasty at the posterior commissure for severe mitral regurgitation (MR), resulting from flail anterior leaflet of the larger postero-medial orifice and dilatation of left ventricle with NCLVM. One year later, he underwent second mitral valve repair for recurrence of MR. Further endoscopic evaluation of the left ventricle, and reinforcement via artificial ring, enabled us to achieve repair.

  3. Two different cardiomyopathies in a single patient : hypertrophic cardiomyopathy and left ventricular noncompaction.

    PubMed

    Sunbul, M; Ozben, B; Mutlu, B

    2013-05-01

    Hypertrophic cardiomyopathy is a complex and relatively common genetic disorder characterized by left ventricular (LV) hypertrophy, usually associated with a nondilated and hyperdynamic chamber with heterogeneous phenotypic expression and clinical course. On the other hand, LV noncompaction is an uncommon cardiomyopathy characterized by the persistence of fetal myocardium with a pattern of prominent trabecular meshwork and deep intertrabecular recesses, systolic dysfunction, and LV dilatation. We report a 29-year-old man with these two different inherent conditions. Our case raises the possibility of a genetic mutation common to these two clinical entities or different gene mutations existing in the same individual.

  4. Left-ventricular non-compaction in a patient with monosomy 1p36.

    PubMed

    Thienpont, Bernard; Mertens, Luc; Buyse, Gunnar; Vermeesch, Joris R; Devriendt, Koen

    2007-01-01

    We report on a new-born girl with left ventricular non-compaction (LVNC), dysmorphism and epilepsy. Array-CGH at 1 Mb resolution revealed a deletion of the terminal 4.6 to 5.9 Mb of the short arm of chromosome 1. Cardiac abnormalities such as dilated cardiomyopathy and structural cardiac defects are common findings in patients with monosomy 1p36. This is however the first report describing LVNC in association with the 1p36 deletion syndrome, broadening the spectrum of cardiac anomalies found in association with this syndrome.

  5. Left ventricular hypertrabeculation/noncompaction associated with coronary heart disease and myopathy.

    PubMed

    Finsterer, Josef; Stöllberger, Claudia; Bonner, Elisabeth

    2011-05-05

    The association of left ventricular hypertrabeculation (LVHT), also known as noncompaction, coronary heart disease, and metabolic myopathy, as presented in the following report, is rare. In a 77-yo male with a history of arterial hypertension, coronary heart disease, dilative cardiomyopathy, mitral and tricuspid insufficiency, AV-block III, implantation of a pacemaker, atrial fibrillation, and heart failure, LVHT was detected on transthoracic echocardiography during hospitalization for worsening heart failure. Clinical neurologic investigation, revealing bilateral ptosis, madarosis, absent eyelashes, bilateral hypacusis, sore neck muscles, generally absent deep tendon reflexes, weakness for foot extension, and ataxic stance, and recurrently elevated creatine-kinase with normal troponine, suggested a metabolic myopathy. Autopsy after death from intractable heart failure. 17 months later confirmed severe coronary heart disease and LVHT in the apex. LVHT may be associated with coronary heart disease and myopathy and may be exclusively located in the left ventricular apex. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  6. Hypertrophic cardiomyopathy associated with left ventricular noncompaction cardiomyopathy and coronary fistulae: a case report. One genotype, three phenotypes?

    PubMed

    Delgado, Anne; Moreira, Davide; Rodrigues, Bruno; Correia, Emanuel; Gama, Pedro; Cabral, Costa; Marinho, António; Santos, Oliveira

    2013-11-01

    The authors present a rare case of hypertrophic cardiomyopathy associated with left ventricular noncompaction cardiomyopathy and coronary artery-left ventricular fistulae in a 42-year-old woman presenting with non-ST-elevation myocardial infarction. Coronary angiography, transthoracic echocardiography and cardiac magnetic resonance revealed the structural abnormalities of the left ventricle and the coronary tree. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  7. Prevalence and Prognostic Significance of Left Ventricular Noncompaction in Patients Referred for Cardiac Magnetic Resonance Imaging.

    PubMed

    Ivanov, Alexander; Dabiesingh, Devindra S; Bhumireddy, Geetha P; Mohamed, Ambreen; Asfour, Ahmed; Briggs, William M; Ho, Jean; Khan, Saadat A; Grossman, Alexandra; Klem, Igor; Sacchi, Terrence J; Heitner, John F

    2017-09-01

    Presence of prominent left ventricular trabeculation satisfying criteria for left ventricular noncompaction (LVNC) on routine cardiac magnetic resonance examination is frequently encountered; however, the clinical and prognostic significance of these findings remain elusive. This registry aimed to assess LVNC prevalence by 4 current criteria and to prospectively evaluate an association between diagnosis of LVNC by these criteria and adverse events. There were 700 patients referred for cardiac magnetic resonance: 42% were women, median age was 70 years (range, 45-71 years), mean left ventricular ejection fraction was 51% (±17%), and 32% had late gadolinium enhancement on cardiac magnetic resonance. The cohort underwent diagnostic assessment for LVNC by 4 separate imaging criteria-referenced by their authors as Petersen, Stacey, Jacquier, and Captur, with LVNC prevalence of 39%, 23%, 25% and 3%, respectively. Primary clinical outcome was combined end point of time to death, ischemic stroke, ventricular tachycardia/ventricular fibrillation, and heart failure hospitalization. Secondary clinical outcomes were (1) all-cause mortality and (2) time to the first occurrence of any of the following events: cardiac death, ischemic stroke, ventricular tachycardia/ventricular fibrillation, or heart failure hospitalization. During a median follow-up of 7 years, there were no statistically significant differences in assessed outcomes noted between patients with and without LVNC irrespective of the applied criteria. Current criteria for the diagnosis of LVNC leads to highly variable disease prevalence in patients referred for cardiac magnetic resonance. The diagnosis of LVNC, by any current criteria, was not associated with adverse clinical events on nearly 7 years of follow-up. Limited conclusions can be made for Captur criteria due to low observed prevalence. © 2017 American Heart Association, Inc.

  8. Coffin-Lowry syndrome and left ventricular noncompaction cardiomyopathy with a restrictive pattern.

    PubMed

    Martinez, Hugo R; Niu, Mary C; Sutton, V Reid; Pignatelli, Ricardo; Vatta, Matteo; Jefferies, John L

    2011-12-01

    Coffin-Lowry syndrome (CLS) is an X-linked dominant condition characterized by moderate to severe mental retardation, characteristic facies, and hand and skeletal malformations. The syndrome is due to mutations in the gene that encodes the ribosomal protein S6 kinase-2, a growth factor-regulating protein kinase located on Xp22.2. Cardiac anomalies are known to be associated with CLS. Left ventricular noncompaction (LVNC) is a clinically heterogeneous disorder characterized by left ventricular (LV) myocardial trabeculations and intertrabecular recesses that communicate with the LV cavity. Patients may present with a variety of clinical phenotypes, ranging from a complete absence of symptoms to a rapid, progressive decline in LV systolic and diastolic function, resulting in congestive heart failure, malignant ventricular tachyarrhythmias, and systemic thromboembolic events. Restrictive cardiomyopathy is an uncommon primary cardiomyopathy characterized by biatrial enlargement, normal or decreased biventricular volume, impaired ventricular filling, and normal or near-normal systolic function. We describe a patient with CLS and LVNC with a restrictive pattern, as documented by echocardiography and cardiac catheterization. To our knowledge, there have been no previous reports of concomitant CLS and LVNC. On the basis of our case, we suggest that patients with CLS be screened not only for congenital structural heart defects but also for LVNC cardiomyopathy.

  9. Cardiomyopathies Due to Left Ventricular Noncompaction, Mitochondrial and Storage Diseases, and Inborn Errors of Metabolism.

    PubMed

    Towbin, Jeffrey A; Jefferies, John Lynn

    2017-09-15

    The normal function of the human myocardium requires the proper generation and utilization of energy and relies on a series of complex metabolic processes to achieve this normal function. When metabolic processes fail to work properly or effectively, heart muscle dysfunction can occur with or without accompanying functional abnormalities of other organ systems, particularly skeletal muscle. These metabolic derangements can result in structural, functional, and infiltrative deficiencies of the heart muscle. Mitochondrial and enzyme defects predominate as disease-related etiologies. In this review, left ventricular noncompaction cardiomyopathy, which is often caused by mutations in sarcomere and cytoskeletal proteins and is also associated with metabolic abnormalities, is discussed. In addition, cardiomyopathies resulting from mitochondrial dysfunction, metabolic abnormalities, storage diseases, and inborn errors of metabolism are described. © 2017 American Heart Association, Inc.

  10. Fibrillin-1 Gene Mutations in Left Ventricular Non-compaction Cardiomyopathy.

    PubMed

    Parent, John J; Towbin, Jeffrey A; Jefferies, John L

    2016-08-01

    Left ventricular non-compaction cardiomyopathy (LVNC) is a unique cardiomyopathy with a current yield of about 30-40 % in identifying a causative gene mutation. A retrospective review of all patients with LVNC at our institution was performed and genetic testing was reviewed. Echocardiographic and cardiac magnetic resonance imaging was reviewed to corroborate the reported phenotype. We present a series of patients with LVNC dilated phenotype associated with fibrillin-1 gene mutations. Fifty-one patients were identified as having LVNC with reduced left ventricular function and/or left ventricular dilation. We retrospectively reviewed gene testing in this cohort when available and identified 5 patients (10 %) with an FBN1 gene mutation. Syndrome breakdown as follows: 3 with Marfan, 1 with Shprintzen-Goldberg, and 1 with no identifiable syndrome. Derangements in fibrillin-1 may impact the compaction process resulting in LVNC. Although causation has not been proven by our report, it certainly raises interest in a possible mechanistic relationship between fibrillin-1 and LVNC given the increased prevalence of Marfan syndrome and fibrillin-1 gene mutations in this cohort.

  11. Cardiomyopathy Phenotypes and Outcomes for Children with Left Ventricular Myocardial Noncompaction: Results from the Pediatric Cardiomyopathy Registry

    PubMed Central

    Jefferies, John L.; Wilkinson, James D.; Sleeper, Lynn A.; Colan, Steven D.; Lu, Minmin; Pahl, Elfriede; Kantor, Paul F.; Everitt, Melanie D.; Webber, Steven A.; Kaufman, Beth D.; Lamour, Jacqueline M.; Canter, Charles E.; Hsu, Daphne T.; Addonizio, Linda J.; Lipshultz, Steven E.; Towbin, Jeffrey A.

    2015-01-01

    Background Left ventricular noncompaction (LVNC) is a distinct form of cardiomyopathy characterized by hypertrabeculation of the left ventricle. The LVNC phenotype may occur in isolation or with other cardiomyopathy phenotypes. Prognosis is incompletely characterized in children. Methods and Results Using diagnoses from the National Heart, Lung, and Blood Institute-funded Pediatric Cardiomyopathy Registry from 1990-2008, 155 of 3219 children (4.8%) had LVNC. Each LVNC patient was also classified as having an associated echocardiographically diagnosed cardiomyopathy phenotype (dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy (RCM), isolated, or indeterminate). The time to death or transplant differed among the phenotypic groups (P = 0.035). Time to listing for cardiac transplantation significantly differed by phenotype (P < 0.001), as did time to transplantation (P = 0.015). The hazard ratio for death/transplant (with isolated LVNC as the reference group) was 4.26 (95% confidence interval [CI], 0.78 to 23.3) for HCM, 6.35 (95% CI, 1.52 to 26.6) for DCM, and 5.66 (95% CI, 1.04 to 30.9) for the indeterminate phenotype. Most events occurred in the first year after diagnosis. Conclusion LVNC is present in at least 5% of children with cardiomyopathy. The specific LVNC-associated cardiomyopathy phenotype predicts the risk of death/transplant and should inform clinical management. PMID:26164213

  12. Cardiomyopathy Phenotypes and Outcomes for Children With Left Ventricular Myocardial Noncompaction: Results From the Pediatric Cardiomyopathy Registry.

    PubMed

    Jefferies, John L; Wilkinson, James D; Sleeper, Lynn A; Colan, Steven D; Lu, Minmin; Pahl, Elfriede; Kantor, Paul F; Everitt, Melanie D; Webber, Steven A; Kaufman, Beth D; Lamour, Jacqueline M; Canter, Charles E; Hsu, Daphne T; Addonizio, Linda J; Lipshultz, Steven E; Towbin, Jeffrey A

    2015-11-01

    Left ventricular noncompaction (LVNC) is a distinct form of cardiomyopathy characterized by hypertrabeculation of the left ventricle. The LVNC phenotype may occur in isolation or with other cardiomyopathy phenotypes. Prognosis is incompletely characterized in children. According to diagnoses from the National Heart, Lung, and Blood Institute-funded Pediatric Cardiomyopathy Registry from 1990 to 2008, 155 of 3,219 children (4.8%) had LVNC. Each LVNC patient was also classified as having an associated echocardiographically diagnosed cardiomyopathy phenotype: dilated (DCM), hypertrophic (HCM), restrictive (RCM), isolated, or indeterminate. The time to death or transplantation differed among the phenotypic groups (P = .035). Time to listing for cardiac transplantation significantly differed by phenotype (P < .001), as did time to transplantation (P = .015). The hazard ratio for death/transplantation (with isolated LVNC as the reference group) was 4.26 (95% confidence interval [CI] 0.78-23.3) for HCM, 6.35 (95% CI 1.52-26.6) for DCM, and 5.66 (95% CI 1.04-30.9) for the indeterminate phenotype. Most events occurred in the 1st year after diagnosis. LVNC is present in at least 5% of children with cardiomyopathy. The specific LVNC-associated cardiomyopathy phenotype predicts the risk of death or transplantation and should inform clinical management. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Left Ventricular Assist Device Insertion in a Patient With Biventricular Noncompaction Cardiomyopathy, Ebstein Anomaly, and a Left Atrial Mass: A Case Report.

    PubMed

    Kumar, Nikhil; Troianos, Christopher A; Baisden, Joshua S

    2016-12-15

    In this report, we present the case of a patient with biventricular noncompaction cardiomyopathy, Ebstein anomaly, and a left atrial mass who required emergent placement of a left ventricular assist device. The noncompaction cardiomyopathy complicated the left ventricular assist device implantation procedure because the thickened, trabeculated myocardium made it difficult to place the inflow cannula. We discuss our perioperative management strategy, in which transesophageal echocardiography was used, to help the surgical team identify the proper cannula placement and provide a bridge to transplantation.

  14. Comparison of Echocardiographic Diagnostic Criteria of Left Ventricular Noncompaction in a Pediatric Population.

    PubMed

    Joong, Anna; Hayes, Denise A; Anderson, Brett R; Zuckerman, Warren A; Carroll, Sheila J; Lai, Wyman W

    2017-08-03

    There is controversy regarding the best echocardiographic diagnostic criteria for left ventricular noncompaction (LVNC). We assessed the diagnostic utility and reproducibility of the previously proposed echocardiographic diagnostic criteria in a pediatric population using a segmental approach. Echocardiograms were matched for patients with and without a clinical diagnosis of LVNC. Blinded reviews of echocardiograms measured (1) depths of intertrabecular recesses (X/Y), (2) noncompaction-to-compaction ratio (NC/C), and (3) number of trabeculations, using a segmental approach. Measurements were analyzed for area under the receiver operating characteristic curves (AUC), sensitivity, and specificity. There were 30 echocardiograms in the initial cohort (15 LVNC cases, 15 controls). Median age was 1.7 years (IQR 0.2-6.9 years) and systolic function was decreased in 40%. Comparison of diagnostic criteria demonstrated the best interrater agreement and AUC with an X/Y ratio measured in end-diastole in the parasternal short axis in the apical anterolateral segment (κ 0.72, CI 0.43-1.00, p value <0.001), yielding 100% sensitivity and 70-86% specificity, among readers. The least predictive and reproducible method was the NC/C ratio. A validation cohort confirmed the superiority of the X/Y ratio, although the interrater agreement and AUC decreased. Measurements according to existing LVNC diagnostic criteria vary by echocardiographic view and segment. Modification of the Chin et al. criteria (Circulation 82:507-513, 1990) using an X/Y ratio <0.5 had the greatest interrater reliability and predictive validity when measured in end-diastole in the parasternal short axis in the apical anterolateral segment. The NC/C ratio had the lowest reliability and predictive validity.

  15. Loss of Function Mutations in NNT Are Associated with Left Ventricular Noncompaction

    PubMed Central

    Bainbridge, Matthew N.; Davis, Erica E.; Choi, Wen-Yee; Dickson, Amy; Martinez, Hugo R.; Wang, Min; Dinh, Huyen; Muzny, Donna; Pignatelli, Ricardo; Katsanis, Nicholas; Boerwinkle, Eric; Gibbs, Richard; Jefferies, John L.

    2015-01-01

    Background Left ventricular noncompaction (LVNC) is an autosomal dominant, genetically heterogeneous cardiomyopathy with variable severity, which may co-occur with cardiac hypertrophy. Methods and Results Here, we generated whole exome sequence (WES) data from multiple members from five families with LVNC. In four out of five families, the candidate causative mutation segregates with disease in known LVNC genes MYH7 and TPM1. Subsequent sequencing of MYH7 in a larger LVNC cohort identified seven novel likely disease causing variants. In the fifth family, we identified a frameshift mutation in NNT, a nuclear encoded mitochondrial protein, not implicated previously in human cardiomyopathies. Resequencing of NNT in additional LVNC families identified a second likely pathogenic missense allele. Suppression of nnt in zebrafish caused early ventricular malformation and contractility defects, likely driven by altered cardiomyocyte proliferation. In vivo complementation studies showed that mutant human NNT failed to rescue nnt morpholino-induced heart dysfunction, indicating a probable haploinsufficiency mechanism. Conclusions Together, our data expand the genetic spectrum of LVNC and demonstrate how the intersection of WES with in vivo functional studies can accelerate the identification of genes that drive human genetic disorders. PMID:26025024

  16. Left ventricular noncompaction: a rare disorder in adults and its association with 1p36 chromosomal anomaly.

    PubMed

    Dod, Harvinder S; Bhardwaj, Ravindra; Hummel, Marybeth; Morise, Anthony P; Batish, Satdev; Warden, Bradford E; Beto, Robert J; Jain, Abnash C

    2010-01-01

    We report on a case of a 25-year-old male with 1p36 deletion syndrome, who was diagnosed with left ventricular noncompaction (LVNC). The association of this rare chromosomal abnormality with LVNC is reported in the pediatric literature, but it has not previously been specifically reported in adults. It is important to diagnose this unclassified cardiomyopathy in the adult population with this chromosomal abnormality for appropriate management and treatment as highlighted in our case.

  17. Left Ventricular Noncompaction Diagnosis and Management Relevant to Pre-participation Screening of Athletes.

    PubMed

    Caselli, Stefano; Attenhofer Jost, Christine H; Jenni, Rolf; Pelliccia, Antonio

    2015-09-01

    Left ventricular noncompaction (LVNC) has been extensively studied over the last years, and an increasing number of cases have been reported worldwide, with a large proportion comprising young and asymptomatic subjects, including athletes. The current epidemic of LVNC is likely the consequence of several causes, that is, the increased awareness of the disease and the refined cardiovascular imaging techniques. The current diagnostic methods, based uniquely on definition of morphologic findings, do not always resolve the overlap of a physiological myocardial architecture comprising a prominent trabecular pattern from a mild phenotypic expression of the real disease. Appropriate criteria for identification and management of LVNC in athletes have, therefore, become a novel challenge for cardiologists and sport physicians, who are required to solve the question of diagnosis and appropriate management in the setting of pre-participation cardiovascular screening. Indeed, although it is important to timely identify a true myocardial disease, to reduce the burden of adverse cardiac event in a young athlete, in contrast, a misdiagnosis of LVNC may lead to unwarranted restriction of the athlete lifestyle, with detrimental psychological, social, and economic consequences. This review report has been planned, therefore, to help physicians in diagnosing and managing athletes presenting with a morphologic pattern suggestive of LVNC with specific focus on criteria for advising sport participation. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. iPSC-derived cardiomyocytes reveal abnormal TGFβ signaling in left ventricular non-compaction cardiomyopathy

    PubMed Central

    Kodo, Kazuki; Ong, Sang-Ging; Jahanbani, Fereshteh; Termglinchan, Vittavat; Hirono, Keiichi; InanlooRahatloo, Kolsoum; Ebert, Antje D.; Shukla, Praveen; Abilez, Oscar J.; Churko, Jared M.; Karakikes, Ioannis; Jung, Gwanghyun; Ichida, Fukiko; Wu, Sean M.; Snyder, Michael P.; Bernstein, Daniel; Wu, Joseph C.

    2016-01-01

    Left ventricular non-compaction (LVNC) is the third most prevalent cardiomyopathy in children and its pathogenesis has been associated with the developmental defect of the embryonic myocardium. We show that patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) generated from LVNC patients carrying a mutation in the cardiac transcription factor TBX20 recapitulate a key aspect of the pathological phenotype at the single-cell level and was associated with perturbed transforming growth factor beta (TGFβ) signaling. LVNC iPSC-CMs have decreased proliferative capacity due to abnormal activation of TGFβ signaling. TBX20 regulates the expression of TGFβ signaling modifiers including a known genetic cause of LVNC, PRDM16, and genome editing of PRDM16 caused proliferation defects in iPSC-CMs. Inhibition of TGFβ signaling and genome correction of the TBX20 mutation were sufficient to reverse the disease phenotype. Our study demonstrates that iPSC-CMs are a useful tool for the exploration of pathological mechanisms underlying poorly understood cardiomyopathies including LVNC. PMID:27642787

  19. Effects of β-blocker therapy on electrocardiographic and echocardiographic characteristics of left ventricular noncompaction.

    PubMed

    Li, Jin; Franke, Jennifer; Pribe-Wolferts, Regina; Meder, Benjamin; Ehlermann, Philipp; Mereles, Derliz; Andre, Florian; Abdelrazek, Mohamed Assem; Merten, Constanze; Schweizer, Patrick A; Becker, Rüdiger; Katus, Hugo A; Thomas, Dierk

    2015-03-01

    Left ventricular noncompaction (LVNC) is a cardiomyopathy with hypertrabeculation of the LV, often complicated by heart failure, arrhythmia and thromboembolic events. The features of LVNC are still incompletely characterized due to its late recognition as clinically relevant condition. The aims of this study were to describe echocardiographic and electrophysiologic characteristics of LVNC patients and to assess the effects of chronic β-blocker treatment. Study patients (n = 20; 42.5 [36.3; 52.5] years; 12 men) exhibited reduced LV ejection fraction (median LVEF = 32 %) and an increased LV mass of 210 g. Sinus rhythm was present in 19 patients, whereas one patient was in atrial fibrillation. Baseline heart rate was 77.5 beats per minute. Left bundle branch block was detected in five cases. In a subgroup of patients receiving β-blocker therapy (n = 17), LV mass was reduced from 226 [178; 306] g to 220 [169; 254] g (p = 0.007) at 13 ± 6 months follow-up. By contrast, a subgroup of three patients that were not treated with an anti-β-adrenergic agent showed LV mass increase from 180 [169; 197] g to 199 [185; 213] g (p = 0.023). LVEF and electrocardiographic parameters were not significantly modulated during chronic β-blocker treatment. There was no sustained symptomatic ventricular tachyarrhythmia, thromboembolic event or death in either group. In conclusion, this study reveals reduction of LV mass among LVNC patients during β-blocker therapy. Effects of β-blocker treatment in LVNC require validation in prospective controlled studies.

  20. Value of cardiovascular MR in diagnosing left ventricular non-compaction cardiomyopathy and in discriminating between other cardiomyopathies.

    PubMed

    Grothoff, Matthias; Pachowsky, Milena; Hoffmann, Janine; Posch, Maximilian; Klaassen, Sabine; Lehmkuhl, Lukas; Gutberlet, Matthias

    2012-12-01

    To analyse the value of cardiovascular magnetic resonance (CMR)-derived myocardial parameters to differentiate left ventricular non-compaction cardiomyopathy (LVNC) from other cardiomyopathies and controls. We retrospectively analysed 12 patients with LVNC, 11 with dilated and 10 with hypertrophic cardiomyopathy and compared them to 24 controls. LVNC patients had to fulfil standard echocardiographic criteria as well as additional clinical and imaging criteria. Cine steady-state free precession and late gadolinium enhancement (LGE) imaging was performed. The total LV myocardial mass index (LV-MMI), compacted (LV-MMI(compacted)), non-compacted (LV-MMI(non-compacted)), percentage LV-MM(non-compacted), ventricular volumes and function were calculated. Data were compared using analysis of variance and Dunnett's test. Additionally, semi-quantitative segmental analyses of the occurrence of increased trabeculation were performed. Total LV-MMI(non-compacted) and percentage LV-MM(non-compacted) were discriminators between patients with LVCN, healthy controls and those with other cardiomyopathies with cut-offs of 15 g/m(2) and 25 %, respectively. Furthermore, trabeculation in basal segments and a ratio of non-compacted/compacted myocardium of ≥3:1 were criteria for LVNC. A combination of these criteria provided sensitivities and specificities of up to 100 %. None of the LVNC patients demonstrated LGE. Absolute CMR quantification of the LV-MMI(non-compacted) or the percentage LV-MM(non-compacted) and increased trabeculation in basal segments allows one to reliably diagnose LVNC and to differentiate it from other cardiomyopathies. Cardiac magnetic resonance imaging can reliably diagnose left ventricular non-compaction cardiomyopathy. Differentiation of LVNC from other cardiomyopathies and normal hearts is possible. The best diagnostic performance can be achieved if combined MRI criteria for the diagnosis are used.

  1. [Echocardiographic diagnosis for ventricular non-compaction cardiomyopathy in foetus and the pathologically comparative study].

    PubMed

    Zhou, Jia; Tian, Leiqi; Zhou, Qichang; Zeng, Shi; Zhou, Jiawei; Zhang, Rongsen; Tong, Hai

    2015-07-01

    目的:研究胎儿心肌致密化不全心肌病(ventricular non-compaction cardiomyopathy,NCCM)的产前超声心动图诊断及其病理特征和心肌超微结构的特点。方法:2004年到2013年产前超声诊断9例胎儿NCCM,观察其产前超声心动图表现,与产后超声心动图或尸体解剖进行对比,并取心肌组织进行病理检查,观察NCCM心肌超微结构特点。结果:NCCM心肌的超声心动图表现为异常粗大的肌小梁、肌小梁隐窝和心肌非致密层厚度/致密层厚度≥2。产前超声心动图诊断9例胎儿NCCM中,6例累及左心室,2例累及双心室,1例累及右心室。其中2例胎儿继续妊娠至分娩,并经产后超声心动图证实,其他7例均选择终止妊娠并经尸体解剖病理证实,心肌组织活检显示NCCM心肌的线粒体和肌小节发育不良、心肌纤维化。结论:通过产前超声心动图诊断NCCM是可行的。胎儿NCCM可以累及左心室、右心室或两个心室。NCCM心肌的线粒体和肌小节成熟度低并伴有心肌纤维化。.

  2. Biventricular noncompaction cardiomyopathy in a patient presenting with new onset seizure: case report.

    PubMed

    Odiete, Oghenerukevwe; Nagendra, Ramanna; Lawson, Mark A; Okafor, Henry

    2012-01-01

    Ventricular noncompaction (VNC) of the myocardium is a rare genetic cardiomyopathy caused by a disorder during endocardial morphogenesis and could be accompanied by life-threatening complications. The major clinical manifestations of VNC are heart failure, arrhythmias, and embolic events. The left ventricle is the most commonly reported affected site, but a few cases of right ventricular involvement have also been reported. We report a case of biventricular noncompaction cardiomyopathy in a 31-year-old woman presenting with a new onset seizure. On the second day of her telemetry-monitored hospitalization, she suffered a witnessed ventricular fibrillation arrest requiring emergency direct-current cardioversion and induced hypothermia. Transthoracic echocardiography (TTE) showed isolated left ventricular (LV) noncompaction and depressed LV systolic function. Subsequent cardiac magnetic resonance imaging (MRI) revealed both left and right ventricular noncompaction. This unusual presentation highlights the importance of a complete and thorough evaluation of patients even when presenting with apparently noncardiac symptom(s).

  3. Left-ventricular non-compaction (LVNC): a clinical feature more often observed in terminal deletion 1p36 than previously expected.

    PubMed

    Cremer, Kirsten; Lüdecke, Hermann-Josef; Ruhr, Frauke; Wieczorek, Dagmar

    2008-01-01

    Deletion of 1p36 (OMIM 607872) is estimated to be the most common distal terminal deletion syndrome. We describe a previously unreported, typically affected two-month-old girl with this microdeletion syndrome, who additionally suffers from left-ventricular non-compaction (LVNC). Recently, this congenital heart defect, characterized by prominent left-ventricular trabeculae and deep intertrabecular recesses, was reported in 12 further patients (excluding those reported only in abstract form) with terminal deletion of 1p36, leading to the conclusion that this cardiomyopathy is common in patients with this chromosomal aberration. We hypothesize that a gene in 1p36 might be responsible for LVNC.

  4. iPSC-derived cardiomyocytes reveal abnormal TGF-β signalling in left ventricular non-compaction cardiomyopathy.

    PubMed

    Kodo, Kazuki; Ong, Sang-Ging; Jahanbani, Fereshteh; Termglinchan, Vittavat; Hirono, Keiichi; InanlooRahatloo, Kolsoum; Ebert, Antje D; Shukla, Praveen; Abilez, Oscar J; Churko, Jared M; Karakikes, Ioannis; Jung, Gwanghyun; Ichida, Fukiko; Wu, Sean M; Snyder, Michael P; Bernstein, Daniel; Wu, Joseph C

    2016-10-01

    Left ventricular non-compaction (LVNC) is the third most prevalent cardiomyopathy in children and its pathogenesis has been associated with the developmental defect of the embryonic myocardium. We show that patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) generated from LVNC patients carrying a mutation in the cardiac transcription factor TBX20 recapitulate a key aspect of the pathological phenotype at the single-cell level and this was associated with perturbed transforming growth factor beta (TGF-β) signalling. LVNC iPSC-CMs have decreased proliferative capacity due to abnormal activation of TGF-β signalling. TBX20 regulates the expression of TGF-β signalling modifiers including one known to be a genetic cause of LVNC, PRDM16, and genome editing of PRDM16 caused proliferation defects in iPSC-CMs. Inhibition of TGF-β signalling and genome correction of the TBX20 mutation were sufficient to reverse the disease phenotype. Our study demonstrates that iPSC-CMs are a useful tool for the exploration of pathological mechanisms underlying poorly understood cardiomyopathies including LVNC.

  5. PLEKHM2 mutation leads to abnormal localization of lysosomes, impaired autophagy flux and associates with recessive dilated cardiomyopathy and left ventricular noncompaction

    PubMed Central

    Muhammad, Emad; Levitas, Aviva; Singh, Sonia R.; Braiman, Alex; Ofir, Rivka; Etzion, Sharon; Sheffield, Val C.; Etzion, Yoram; Carrier, Lucie; Parvari, Ruti

    2015-01-01

    Gene mutations, mostly segregating with a dominant mode of inheritance, are important causes of dilated cardiomyopathy (DCM), a disease characterized by enlarged ventricular dimensions, impaired cardiac function, heart failure and high risk of death. Another myocardial abnormality often linked to gene mutations is left ventricular noncompaction (LVNC) characterized by a typical diffuse spongy appearance of the left ventricle. Here, we describe a large Bedouin family presenting with a severe recessive DCM and LVNC. Homozygosity mapping and exome sequencing identified a single gene variant that segregated as expected and was neither reported in databases nor in Bedouin population controls. The PLEKHM2 cDNA2156_2157delAG variant causes the frameshift p.Lys645AlafsTer12 and/or the skipping of exon 11 that results in deletion of 30 highly conserved amino acids. PLEKHM2 is known to interact with several Rabs and with kinesin-1, affecting endosomal trafficking. Accordingly, patients' primary fibroblasts exhibited abnormal subcellular distribution of endosomes marked by Rab5, Rab7 and Rab9, as well as the Golgi apparatus. In addition, lysosomes appeared to be concentrated in the perinuclear region, and autophagy flux was impaired. Transfection of wild-type PLEKHM2 cDNA into patient's fibroblasts corrected the subcellular distribution of the lysosomes, supporting the causal effect of PLEKHM2 mutation. PLEKHM2 joins LAMP-2 and BAG3 as a disease gene altering autophagy resulting in an isolated cardiac phenotype. The association of PLEKHM2 mutation with DCM and LVNC supports the importance of autophagy for normal cardiac function. PMID:26464484

  6. Assessment of tenascin-C levels in ventricular noncompaction/hypertrabeculation patients: a cross-sectional study.

    PubMed

    Erer, Hatice Betul; Guvenc, Tolga Sinan; Kemik, Ahu Sarbay; Yilmaz, Hale; Kul, Seref; Altay, Servet; Oz, Dilaver; Zeren, Gonul; Ekmekci, Ahmet; Zencirci, Aycan Esen; Sayar, Nurten; Eren, Mehmet

    2014-02-01

    Ventricular noncompaction/hypertrabeculation (NC/HT) is a rare form of congenital cardiomyopathy. We aimed to investigate the presence of serum tenascin-C (TN-C) in adult patients with NC/HT and evaluate its value. Serum TN-C levels were measured by ELISA in 50 NC/HT patients both with/without systolic dysfunction and in 23 normal controls. Systolic dysfunction was defined as ejection fraction (EF) ≤ 40. Mann-Whitney U-test and ROC curve analysis were done. Of 49 NC/HT patients, 24 (49%) patients had systolic dysfunction (mean age 36 ± 15) and 25 patients (51%) had normal systolic function (mean age 36 ± 17). The ages between groups were not different. The mean levels of serum TN-C in patients with or without systolic dysfunction were 26 ± 10 ng/mL and 26 ± 8 ng/mL respectively, compared to normal controls, 7 ± 2 ng/mL (P < 0.001). No significance was observed between 2 groups of NC/HT patients regarding TN-C levels (P = 0.8). The ROC curve analysis revealed that a TN-C value of 11.7 ng/mL identified patients with NC/HT with 100% sensitivity and specifity. High serum TN-C levels are present in adult NC/HT cardiomyopathy even when left ventricular systolic function remains normal. Also, serum TN-C levels could be regarded as a candidate biomarker in the diagnosis of NC/HT which needs to be tested in larger prospective studies. © 2013, Wiley Periodicals, Inc.

  7. Biventricular non-compaction with predominant right ventricular involvement, reduced left ventricular systolic and diastolic function, and pulmonary hypertension in a Hispanic male

    PubMed Central

    Said, Sarmad; Cooper, Chad J.; Quevedo, Karla; Rodriguez, Emmanuel; Hernandez, German T.

    2013-01-01

    Patient: Male, 22 Final Diagnosis: Cardiomyopathy Symptoms: Shortness of breath • dispnoea • chest discomfort Medication: — Clinical Procedure: Echocardiogram • cardiac MRI Specialty: Cardiology Objective: Challenging differential diagnosis Background: Non-compaction cardiomyopathy (NCM) is a rare congenital cardiomyopathy characterized by increased trabeculation in one or more segments of the ventricle. The left ventricle is most commonly affected. However, biventricular involvement or right ventricle predominance has also been described. Clinical features of NCM are non-specific and can range from being asymptomatic to symptoms of congestive heart failure, arrhythmia, and systemic thromboembolism. Case Report: 22-year-old Hispanic male presented with two month history of chest discomfort. Laboratory workup revealed an elevated brain-natriuretic-peptide of 1768 pg/ml. ECG and chest x-ray was nonspecific. Transthoracic echocardiogram revealed prominent trabeculae and spongiform appearance of the left ventricle (LV) with an ejection-fraction of 15–20%; 5 of 9 segments of the LV were trabeculated with deep intertrabecular recesses also involving the right ventricle (RV) with demonstrated blood flow in these recesses on color-doppler. The biventricular spongiform appearance was morphologically suggestive for NCM with involvement of the RV. Confirmatory cardiac MRI was performed, demonstrating excessive trabeculation of the left-ventricular apex and mid-ventricular segments. Hypertrabecularion was exhibited at the apical and lateral wall of the RV. Cardiac catheterization showed an intact cardiac vessel system. The patient was discharged on heart failure treatment and was placed on the heart transplantation list. Conclusions: NCM is a unique disorder resulting in serious and severe complications. The majority of the reported cases describe the involvement of the left ventricle. However, the right ventricle should be taken into careful consideration. The early

  8. Biventricular non-compaction with predominant right ventricular involvement, reduced left ventricular systolic and diastolic function, and pulmonary hypertension in a Hispanic male.

    PubMed

    Said, Sarmad; Cooper, Chad J; Quevedo, Karla; Rodriguez, Emmanuel; Hernandez, German T

    2013-01-01

    Male, 22 FINAL DIAGNOSIS: Cardiomyopathy Symptoms: Shortness of breath • dispnoea • chest discomfort - Clinical Procedure: Echocardiogram • cardiac MRI Specialty: Cardiology. Challenging differential diagnosis. Non-compaction cardiomyopathy (NCM) is a rare congenital cardiomyopathy characterized by increased trabeculation in one or more segments of the ventricle. The left ventricle is most commonly affected. However, biventricular involvement or right ventricle predominance has also been described. Clinical features of NCM are non-specific and can range from being asymptomatic to symptoms of congestive heart failure, arrhythmia, and systemic thromboembolism. 22-year-old Hispanic male presented with two month history of chest discomfort. Laboratory workup revealed an elevated brain-natriuretic-peptide of 1768 pg/ml. ECG and chest x-ray was nonspecific. Transthoracic echocardiogram revealed prominent trabeculae and spongiform appearance of the left ventricle (LV) with an ejection-fraction of 15-20%; 5 of 9 segments of the LV were trabeculated with deep intertrabecular recesses also involving the right ventricle (RV) with demonstrated blood flow in these recesses on color-doppler. The biventricular spongiform appearance was morphologically suggestive for NCM with involvement of the RV. Confirmatory cardiac MRI was performed, demonstrating excessive trabeculation of the left-ventricular apex and mid-ventricular segments. Hypertrabecularion was exhibited at the apical and lateral wall of the RV. Cardiac catheterization showed an intact cardiac vessel system. The patient was discharged on heart failure treatment and was placed on the heart transplantation list. NCM is a unique disorder resulting in serious and severe complications. The majority of the reported cases describe the involvement of the left ventricle. However, the right ventricle should be taken into careful consideration. The early diagnosis may help to increase the event-free survival.

  9. Novel findings of left ventricular non-compaction cardiomyopathy, microform cleft lip and poor vision in patient with SMC1A-associated Cornelia de Lange syndrome.

    PubMed

    Wenger, Tara L; Chow, Penny; Randle, Stephanie C; Rosen, Anna; Birgfeld, Craig; Wrede, Joanna; Javid, Patrick; King, Darcy; Manh, Vivian; Hing, Anne V; Albers, Erin

    2017-02-01

    Relatively few patients with Cornelia de Lange syndrome (CdLS) due to SMC1A mutation have been reported, limiting understanding of the full extent of the phenotype. Compared to children with classic NIPBL-associated CdLS, patients with SMC1A-associated CdLS have a milder physical phenotype with prominent intellectual disability, high rate of cleft palate and absence of limb reductions. We present a patient with SMC1A-associated CdLS who had typical features including developmental delay, seizure disorder, feeding difficulties, hirsutism, and cleft palate. She also was found to have three novel features: (i) left ventricular non-compaction (LVNC) cardiomyopathy; (ii) microform cleft lip; and (iii) severe hyperopia and astigmatism. These features have implications regarding potential insight into the pathogenesis of the disorder, screening, and medical management. Hypertrophic cardiomyopathy has previously been reported in SMC1A-associated CdLS, but to our knowledge this is the first reported child with LVNC. Previous reports have included children with isolated clefts of the palate without involvement of the lip. When cleft palate alone is associated with a disorder, the underlying pathophysiology for clefting is sometimes secondary due to mechanical blocking of the fusion of the palatal shelves with the developing tongue. The presence of microform cleft lip in this patient suggests that the pathophysiology of clefting in SMC1A is primary rather than secondary. Few studies report ophthalmologic findings specific to SMC1A. Based on these findings, LVNC cardiomyopathy and cleft lip should be considered features of SMC1A-associated CdLS. All patients should receive echocardiogram and undergo thorough ophthalmologic evaluation as part of routine CdLS care. © 2016 Wiley Periodicals, Inc.

  10. Bilateral perisylvian polymicrogyria, periventricular nodular heterotopia, and left ventricular noncompaction in a girl with 10.5-11.1 Mb terminal deletion of 1p36.

    PubMed

    Saito, Shoji; Kawamura, Rie; Kosho, Tomoki; Shimizu, Takashi; Aoyama, Koki; Koike, Kenichi; Wada, Takahito; Matsumoto, Naomichi; Kato, Mitsuhiro; Wakui, Keiko; Fukushima, Yoshimitsu

    2008-11-15

    Monosomy 1p36 is a common subtelomeric microdeletion syndrome, characterized by craniofacial dysmorphisms, developmental delay, mental retardation, hypotonia, epilepsy, cardiovascular complications, and hearing impairment; deleted regions have been mapped within 10.0 Mb from the telomere in most documented cases. We report on a girl with a 10.5-11.1 Mb terminal deletion of 1p36 shown by fluorescence in situ hybridization (FISH). She had three distinct structural abnormalities: bilateral perisylvian polymicrogyria, periventricular nodular heterotopia, and left ventricular noncompaction. She died in early infancy with intractable epilepsy, progressive congestive heart failure and pulmonary hypertension. To date, this is the first case with monosomy 1p36, complicated by this combination of manifestations; she is also the first who had possibly a simple terminal deletion of 1p36 and died in early infancy. An atypically large deletion in this patient might be the basis for the development of these features and the severe clinical course.

  11. Ebstein anomaly, left ventricular non-compaction, and early onset heart failure associated with a de novo α-tropomyosin gene mutation.

    PubMed

    Kelle, Angela M; Bentley, S Jared; Rohena, Luis O; Cabalka, Allison K; Olson, Timothy M

    2016-08-01

    Ebstein anomaly of the tricuspid valve (EA) can be associated with left ventricular non-compaction (LVNC), a rare congenital cardiomyopathy. We report a 2 year-old female with EA and severe tricuspid regurgitation, LVNC, pulmonary hypertension, and chronic biventricular systolic heart failure, who died during evaluation for cardiac transplantation. Gene panel testing revealed a heterozygous de novo missense mutation in TPM1, which encodes the cardiac sarcomeric thin filament protein α-tropomyosin. The c.475G>A variant results in a p.Asp159Asn substitution, altering a highly conserved residue predicted to be damaging to protein structure and function. TPM1 is the second gene linked to EA with LVNC in humans, implicating overlap in the molecular basis of structural and myopathic heart disease. © 2016 Wiley Periodicals, Inc.

  12. Combination of Whole Genome Sequencing, Linkage, and Functional Studies Implicates a Missense Mutation in Titin as a Cause of Autosomal Dominant Cardiomyopathy With Features of Left Ventricular Noncompaction

    PubMed Central

    Hastings, Robert; de Villiers, Carin P.; Hooper, Charlotte; Ormondroyd, Liz; Pagnamenta, Alistair; Lise, Stefano; Salatino, Silvia; Knight, Samantha J.L.; Taylor, Jenny C.; Thomson, Kate L.; Arnold, Linda; Chatziefthimiou, Spyros D.; Konarev, Petr V.; Wilmanns, Matthias; Ehler, Elisabeth; Ghisleni, Andrea; Gautel, Mathias; Blair, Edward; Watkins, Hugh

    2016-01-01

    Background— High throughput next-generation sequencing techniques have made whole genome sequencing accessible in clinical practice; however, the abundance of variation in the human genomes makes the identification of a disease-causing mutation on a background of benign rare variants challenging. Methods and Results— Here we combine whole genome sequencing with linkage analysis in a 3-generation family affected by cardiomyopathy with features of autosomal dominant left ventricular noncompaction cardiomyopathy. A missense mutation in the giant protein titin is the only plausible disease-causing variant that segregates with disease among the 7 surviving affected individuals, with interrogation of the entire genome excluding other potential causes. This A178D missense mutation, affecting a conserved residue in the second immunoglobulin-like domain of titin, was introduced in a bacterially expressed recombinant protein fragment and biophysically characterized in comparison to its wild-type counterpart. Multiple experiments, including size exclusion chromatography, small-angle x ray scattering, and circular dichroism spectroscopy suggest partial unfolding and domain destabilization in the presence of the mutation. Moreover, binding experiments in mammalian cells show that the mutation markedly impairs binding to the titin ligand telethonin. Conclusions— Here we present genetic and functional evidence implicating the novel A178D missense mutation in titin as the cause of a highly penetrant familial cardiomyopathy with features of left ventricular noncompaction. This expands the spectrum of titin’s roles in cardiomyopathies. It furthermore highlights that rare titin missense variants, currently often ignored or left uninterpreted, should be considered to be relevant for cardiomyopathies and can be identified by the approach presented here. PMID:27625337

  13. Next-generation sequencing (NGS) as a fast molecular diagnosis tool for left ventricular noncompaction in an infant with compound mutations in the MYBPC3 gene.

    PubMed

    Schaefer, Elise; Helms, Pauline; Marcellin, Luc; Desprez, Philippe; Billaud, Philippe; Chanavat, Valérie; Rousson, Robert; Millat, Gilles

    2014-03-01

    Left ventricular noncompaction (LVNC) is a clinically heterogeneous disorder characterized by a trabecular meshwork and deep intertrabecular myocardial recesses that communicate with the left ventricular cavity. LVNC is classified as a rare genetic cardiomyopathy. Molecular diagnosis is a challenge for the medical community as the condition shares morphologic features of hypertrophic and dilated cardiomyopathies. Several genetic causes of LVNC have been reported, with variable modes of inheritance, including autosomal dominant and X-linked inheritance, but relatively few responsible genes have been identified. In this report, we describe a case of a severe form of LVNC leading to death at 6 months of life. NGS sequencing using a custom design for hypertrophic cardiomyopathy panel allowed us to identify compound heterozygosity in the MYBPC3 gene (p.Lys505del, p.Pro955fs) in 3 days, confirming NGS sequencing as a fast molecular diagnosis tool. Other studies have reported neonatal presentation of cardiomyopathies associated with compound heterozygous or homozygous MYBPC3 mutations. In this family and in families in which parental truncating MYBPC3 mutations are identified, preimplantation or prenatal genetic screening should be considered as these genotypes leads to neonatal mortality and morbidity.

  14. Myocardial Noncompaction Presenting With Myocardial Bridge

    PubMed Central

    Shen, Yuechun; Li, Xinchun; Lu, Dongfeng; Xiao, Aiyi; Li, Jun

    2015-01-01

    Abstract Myocardial noncompaction, namly isolated noncompaction of the left ventricular myocardium (NVM), is a rare congenital disease. It can be either seen in the absence of other cardiac anomalies, or associated with other congenital cardiac defects, mostly stenotic lesions of the left ventricular outflow tract. A myocardial bridge (MB) is thought being associated with coronary heart disease, such as coronary spasm, arrhythmia, and so on. The significance of MB in association with other congenital cardiac conditions is unknown. We report a novel case who was presented NVM and MB. A 34-year-old man complained of chest prickling-like pain and dizzy for 1 year. His blood pressure was 110/70 mm Hg. Echocardiograph revealed increased trabeculations below the level of papillary muscle of left ventricle (LV); deep intertrabecular recesses in the endocardial wall of LV particularly in apex free wall; and LV ejection fraction of 57%. A coronary computerized tomography scan showed that part, 38.9 cm, of left descending artery tunnel was surrounding by cardiac muscles rather than resting on top of the myocardium. The therapeutics interventions included lifestyle cares, agents of anti-ischemia and improvement myocardial cell metabolism. The patient was followed up for 2.6 years, and his general condition was stable. This case indicates that NVM can be developed with MB, and the complete diagnosis of NVM and MB should be made by different image studies. PMID:26356695

  15. AB0 system and D(Rh o) antigen frequencies in left ventricular hypertrabeculation/noncompaction in relation to cardiac and neuromuscular findings.

    PubMed

    Stöllberger, C; Krugluger, W; Winkler-Dworak, M; Finsterer, J

    2008-10-30

    Left ventricular hypertrabeculation/noncompaction (LVHT) is a cardiac abnormality with suspected genetic background, characterized by trabeculations and intertrabecular recesses. Aim of the study in LVHT patients was to assess the AB0 system and D(Rh(o)) antigen frequencies, to look for an association between the prevalence of cardiac and neuromuscular abnormalities and to compare distribution of the AB0 system and D(Rh(o)) antigen frequencies with the Austrian general population. In 77/102 LVHT patients (75%) information about blood group could be obtained. There were no differences in the prevalence of clinical, electrocardiographic and echocardiographic findings and neuromuscular disorders between the AB0 blood groups. When comparing 67 LVHT patients who were D(Rh(o)) antigen positive with 10 patients who were D(Rh(o)) antigen negative, no differences could be found. Among LVHT patients, 0 D(Rh(o)) antigen positive was the most frequent (39%) followed by A D(Rh(o)) antigen positive (34%). In the Austrian general population A D(Rh(o)) antigen positive was the most frequent (33%) followed by 0 D(Rh(o)) antigen positive (30%). This study shows that LVHT patients do not differ according the blood groups, and that the distribution of blood groups is only minimally different between LVHT patients and the general Austrian population.

  16. Use of cardiac magnetic resonance imaging to determine myocardial viability in an infant with in utero septal myocardial infarction and ventricular noncompaction.

    PubMed

    Whitham, Jennifer K E; Hasan, Babar S; Schamberger, Marcus S; Johnson, Tiffanie R

    2008-09-01

    We describe the use of cardiac magnetic resonance imaging (CMRI) to determine myocardial viability and subsequently clinical prognosis in a patient with in utero septal myocardial infarction (MI) and dilated cardiomyopathy. MI is most commonly associated with congenital heart disease. These lesions include aortic atresia and stenosis, interrupted aortic arch, hypoplastic left ventricle (LV), and total anomalous pulmonary venous return (TAPVR). Within the last decade, it has been clearly established that systolic dysfunction is not always a definitive status after MI. In the presence of residual viable myocardium and an adequate myocardial perfusion, contractility might normalize-this process being related to a remarkable prognostic benefit. Until the use of CMRI, myocardial viability has been poorly characterized by other imaging modalities, thus making prognosis difficult to predict. Using myocardial delayed-enhancement CMRI, this patient was shown to have a dilated left ventricle with noncompaction, longitudinal midwall hyperenhancement consistent with nonviable tissue, and severely diminished left ventricular function. In conclusion, CMRI is the only imaging modality that can define anatomy, function, and tissue characterization simultaneously. In the future, CMRI could circumvent the need for more invasive diagnostic procedures in determining the cause and prognosis of patients with dilated cardiomyopathy and myocardial infarction.

  17. Complications Associated With Implantable Cardioverter Defibrillators in Adults With Congenital Heart Disease or Left Ventricular Noncompaction Cardiomyopathy (From the NCDR(®) Implantable Cardioverter-Defibrillator Registry).

    PubMed

    Gleva, Marye J; Wang, Yongfei; Curtis, Jeptha P; Berul, Charles I; Huddleston, Charles B; Poole, Jeanne E

    2017-08-08

    Patients with childhood heart disease are living longer and entering adulthood, and may undergo implantable cardioverter-defibrillator (ICD) implantation to reduce the risk of sudden death. We evaluated the characteristics of adult patients with congenital heart disease or left ventricular noncompaction cardiomyopathy (LVNC) in the National Cardiovascular Disease Registry ICD Registry and determined ICD-related in-hospital complications. Patients with LVNC or transposition of the great arteries, tetralogy of Fallot, Ebstein's anomaly, atrial septal defect, ventricular septal defect, or common ventricle were identified in the registry. In-hospital complications were compared among different diagnoses using the chi-square test for categorical variables and the F-test in analyses of variance for continuous variables. A total of 3,077 patients were identified. The mean age was 48.0 ± 16.0 years, and 39.9% were female. Single-chamber ICDs were implanted in 25.2%, dual chamber in 41.9%, and cardiac resynchronization in 30.8%. Intraprocedural or postprocedural complications occurred in 70 patients (2.3%); there were 6 in-hospital deaths (0.2%). The most frequent complications were acute lead dislodgments, pneumothorax, and hematomas. Patients with Ebstein's anomaly had the greatest complication rate (8.3%, p = 0.03). The complication rate was 1.55% in single-chamber devices, 1.86% in dual chamber, and 3.5% in cardiac resynchronization (p < 0.001). For initial implants, the complication rate was 2.55%, 1.62% in generator replacements, and 8.77% in lead revisions (p = 0.001). In conclusion, in this large contemporary adult cohort of congenital heart disease and LVNC patients who underwent ICD implant procedures, periprocedural complication rates were low. Lead-related risks predominated. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. A Case of Fetal Diagnosis of Noncompaction Cardiomyopathy and Coarctation of the Aorta

    PubMed Central

    Jacobs, Katherine; Giacobbe, Lauren; Aguilera, Marijo; Ramin, Kirk; Sivanandam, Shanthi

    2014-01-01

    Background Left ventricular noncompaction (LVNC) cardiomyopathy is a rare form of cardiomyopathy. It is difficult to diagnose prenatally and therefore not well described in the fetal population. There have been a few reports in the literature detailing isolated cases of fetal and neonatal LVNC cardiomyopathy. Case Report We present a case of LVNC cardiomyopathy and coarctation of the aorta detected prenatally at 29 + 6 weeks of gestation with survival in infancy. This is the first case report in the literature describing the fetal diagnosis of noncompaction cardiomyopathy and associated coarctation of the aorta; a rare combination. Conclusion  With a high index of suspicion, the antenatal diagnosis of noncompaction cardiomyopathy may improve neonatal morbidity and mortality. PMID:25032060

  19. Loss-of-Function of hNav1.5 by ZASP1-D117N Associated with Intraventricular Conduction Disturbances in Left Ventricular Noncompaction

    PubMed Central

    Xi, Yutao; Ai, Tomohiko; De Lange, Enno; Li, Zhaohui; Wu, Geru; Brunelli, Luca; Kyle, W. Buck; Turker, Isik; Cheng, Jie; Ackerman, Michael J.; Kimura, Akinori; Weiss, James N.; Qu, Zhilin; Kim, Jeffrey J.; Faulkner, Georgine; Vatta, Matteo

    2013-01-01

    Background Defects of cytoarchitectural proteins can cause left ventricular noncompaction (LVNC), which is often associated with conduction system diseases. We have previously identified a p.D117N mutation in the LDB3-encoding Z-band Alternatively Spliced PDZ motif gene (ZASP) in a patient with LVNC and conduction disturbances. We sought to investigate a role of p.D117N mutation in the LBD3 NM_001080114.1 isoform (ZASP1-D117N) in the regulation of cardiac sodium channel (Nav1.5) that plays an important role in the cardiac conduction system. Methods and Results Effects of ZASP1-wt and ZASP1-D117N on Nav1.5 were studied in HEK-293 cells and neonatal rat cardiomyocytes (NRCMs). Patch-clamp study demonstrated that ZASP1-D117N significantly attenuated INa by 27% in HEK-293 cells and by 32% in NRCMs. In addition, ZASP1-D117N rightward shifted the voltage-dependent activation and inactivation in both systems. In silico simulation using Luo-Rudy phase 1 model demonstrated that altered Nav1.5 function can reduce cardiac conduction velocity by 28% compared to the control. Pull-down assays showed that both wt and ZASP1-D117N can complex with Nav1.5 and telethonin/T-Cap, which required intact PDZ domains. Immunohistochemical staining in NRCMs demonstrates that ZASP1-D117N did not significantly disturb the Z-line structure. Disruption of cytoskeletal networks with ML-7 and cytochalasin D abolished the effects of ZASP1-D117N on the Nav1.5. Conclusions ZASP1 can form protein complex with telethonin/T-Cap and Nav1.5. The LVNC-specific ZASP1 mutation can cause loss-of-function of Nav1.5 without significant alteration of the cytoskeletal protein complex. Our study suggests that electrical remodeling can occur in LVNC subject due to a direct effect of mutant ZASP on Nav1.5. PMID:22929165

  20. [Association of Wolff-Parkinson-White syndrome with isolated non-compaction of the left ventricle: a case report].

    PubMed

    Brembilla-Perrot, B; Codreanu, A; Marie, P Y; Beurrier, D; Husson, J L; Hutin, O; Pruna, A; Yangni N'Da, O; Ernst, Y; Bosser, G

    2006-06-01

    The Wolff-Parkinson-White syndrome (WPW) may be associated with a number of cardiac pathologies, especially congenital disease, in 7.5 to 17% of cases. The authors report a rare association of the WPW syndrome with two Kent bundles, right and left septal, with non-compaction of the left ventricle in a 52 year old man. This was a chance finding during systematic echocardiography after ablation, and confirmed by cardiac MRI. The patient was asymptomatic.

  1. Arrhythmogenic Noncompaction Cardiomyopathy: Is There an Echocardiographic Phenotypic Overlap of Two Distinct Cardiomyopathies?

    PubMed

    Aras, Dursun; Ozeke, Ozcan; Cay, Serkan; Ozcan, Firat; Baser, Kazım; Dogan, Umuttan; Unlu, Murat; Demirkan, Burcu; Tufekcioglu, Omac; Topaloglu, Serkan

    2015-09-01

    The clinical diagnosis of right ventricular (RV) cardiomyopathies is often challenging. It is difficult to differentiate the isolated left ventricular (LV) noncompaction cardiomyopathy (NC) from biventricular NC or from coexisting arrhythmogenic ventricular cardiomyopathy (AC). There are currently few established morphologic criteria for the diagnosis other than RV dilation and presence of excessive regional trabeculation. The gross and microscopic changes suggest pathological similarities between, or coexistence of, RV-NC and AC. Therefore, the term arrhythmogenic right ventricular cardiomyopathy is somewhat misleading as isolated LV or biventricular involvement may be present and thus a broader term such as AC should be preferred. We describe an unusual case of AC associated with a NC in a 27-year-old man who had a history of permanent pacemaker 7 years ago due to second-degree atrioventricular block.

  2. Noncompaction myocardium in association with type Ib glycogen storage disease.

    PubMed

    Goeppert, Benjamin; Lindner, Martin; Vogel, Monika Nadja; Warth, Arne; Stenzinger, Albrecht; Renner, Marcus; Schnabel, Philipp; Schirmacher, Peter; Autschbach, Frank; Weichert, Wilko

    2012-10-15

    Noncompaction myocardium is a rare disorder assumed to occur as an arrest of the compaction process during the normal development of the heart. Left ventricular noncompaction has been reported to be associated with a variety of cardiac and extracardiac, especially neuromuscular abnormalities. Moreover, it has been suggested that metabolic alterations could be responsible for the noncompaction. However, no association of noncompaction myocardium with type Ib glycogen storage disease (GSD) has been reported so far. Type Ib GSD is due to a defect of a transmembrane protein which results, similar to type Ia GSD, in hypoglycemia, a markedly enlarged liver and, additionally, in neutropenia, recurrent infections, and inflammatory bowel disease. Until now, no muscular or cardiac involvement has been described in type Ib GSD patients. The present case represents the first report of a noncompaction myocardium in a child with type Ib GSD who died of sudden clinical deterioration at the age of four.

  3. Cardiac beta-myosin heavy chain defects in two families with non-compaction cardiomyopathy: linking non-compaction to hypertrophic, restrictive, and dilated cardiomyopathies.

    PubMed

    Hoedemaekers, Yvonne M; Caliskan, Kadir; Majoor-Krakauer, Danielle; van de Laar, Ingrid; Michels, Michelle; Witsenburg, Maarten; ten Cate, Folkert J; Simoons, Maarten L; Dooijes, Dennis

    2007-11-01

    Cardiomyopathies are classified according to distinct morphological characteristics. They occur relatively frequent and are an important cause of mortality and morbidity. Isolated ventricular non-compaction or non-compaction cardiomyopathy (NCCM) is characterized by an excessively thickened endocardial layer with deep intertrabecular recesses, reminiscent of the myocardium during early embryogenesis. Aims Autosomal-dominant as well as X-linked inheritance for NCCM has been described and several loci have been associated with the disease. Nevertheless, a major genetic cause for familial NCCM remains to be identified. Methods and Results We describe, in two separate autosomal-dominant NCCM families, the identification of mutations in the sarcomeric cardiac beta-myosin heavy chain gene (MYH7), known to be associated with hypertrophic cardiomyopathy (HCM), restricted cardiomyopathy (RCM), and dilated cardiomyopathy (DCM). Conclusion These results confirm the genetic heterogeneity of NCCM and suggest that the molecular classification of cardiomyopathies includes an MYH7-associated spectrum of NCCM with HCM, RCM, and DCM.

  4. Isolated Right Ventricular Infarction after Modified Cabrol Operation

    PubMed Central

    Pappy, Reji M.; Hanna, Elias B.; Peyton, Marvin D.; Saucedo, Jorge F.

    2012-01-01

    We report the case of a 27-year-old woman with a rare presentation of right ventricular failure secondary to isolated right ventricular myocardial infarction, 3 weeks after an uncommon surgical procedure, the modified Cabrol operation. Her medical history also included a Ross procedure at the age of 12 years. On the basis of her subacute presentation and a consultation with cardiac surgeons, we decided on medical management. Follow-up echocardiography at 6 months revealed that the right ventricular systolic function remained severely impaired, but the patient was asymptomatic with excellent functional capacity. We review the surgical techniques of aortic graft replacement and their respective complications. We also discuss the impact of conservative and reperfusion strategies on prognosis and long-term outcomes in the setting of right ventricular infarction. PMID:22412249

  5. Isolated right ventricular infarction after modified Cabrol operation.

    PubMed

    Pappy, Reji M; Hanna, Elias B; Peyton, Marvin D; Saucedo, Jorge F

    2012-01-01

    We report the case of a 27-year-old woman with a rare presentation of right ventricular failure secondary to isolated right ventricular myocardial infarction, 3 weeks after an uncommon surgical procedure, the modified Cabrol operation. Her medical history also included a Ross procedure at the age of 12 years. On the basis of her subacute presentation and a consultation with cardiac surgeons, we decided on medical management. Follow-up echocardiography at 6 months revealed that the right ventricular systolic function remained severely impaired, but the patient was asymptomatic with excellent functional capacity.We review the surgical techniques of aortic graft replacement and their respective complications. We also discuss the impact of conservative and reperfusion strategies on prognosis and long-term outcomes in the setting of right ventricular infarction.

  6. Common arterial trunk and ventricular non-compaction in Lrp2 knockout mice indicate a crucial role of LRP2 in cardiac development.

    PubMed

    Baardman, Maria E; Zwier, Mathijs V; Wisse, Lambertus J; Gittenberger-de Groot, Adriana C; Kerstjens-Frederikse, Wilhelmina S; Hofstra, Robert M W; Jurdzinski, Angelika; Hierck, Beerend P; Jongbloed, Monique R M; Berger, Rolf M F; Plösch, Torsten; DeRuiter, Marco C

    2016-04-01

    Lipoprotein-related receptor protein 2 (LRP2) is important for development of the embryonic neural crest and brain in both mice and humans. Although a role in cardiovascular development can be expected, the hearts ofLrp2knockout (KO) mice have not yet been investigated. We studied the cardiovascular development ofLrp2KO mice between embryonic day 10.5 (E10.5) and E15.5, applying morphometry and immunohistochemistry, using antibodies against Tfap2α (neural crest cells), Nkx2.5 (second heart field), WT1 (epicardium derived cells), tropomyosin (myocardium) and LRP2. TheLrp2KO mice display a range of severe cardiovascular abnormalities, including aortic arch anomalies, common arterial trunk (persistent truncus arteriosus) with coronary artery anomalies, ventricular septal defects, overriding of the tricuspid valve and marked thinning of the ventricular myocardium. Both the neural crest cells and second heart field, which are essential for the lengthening and growth of the right ventricular outflow tract, are abnormally positioned in theLrp2KO. This explains the absence of the aorto-pulmonary septum, which leads to common arterial trunk and ventricular septal defects. Severe blebbing of the epicardial cells covering the ventricles is seen. Epithelial-mesenchymal transition does occur; however, there are fewer WT1-positive epicardium-derived cells in the ventricular wall as compared to normal, coinciding with the myocardial thinning and deep intertrabecular spaces. LRP2 plays a crucial role in cardiovascular development in mice. This corroborates findings of cardiac anomalies in humans withLRP2mutations. Future studies should reveal the underlying signaling mechanisms in which LRP2 is involved during cardiogenesis. © 2016. Published by The Company of Biologists Ltd.

  7. Common arterial trunk and ventricular non-compaction in Lrp2 knockout mice indicate a crucial role of LRP2 in cardiac development

    PubMed Central

    Baardman, Maria E.; Zwier, Mathijs V.; Wisse, Lambertus J.; Gittenberger-de Groot, Adriana C.; Kerstjens-Frederikse, Wilhelmina S.; Hofstra, Robert M. W.; Jurdzinski, Angelika; Hierck, Beerend P.; Jongbloed, Monique R. M.; Berger, Rolf M. F.; Plösch, Torsten; DeRuiter, Marco C.

    2016-01-01

    ABSTRACT Lipoprotein-related receptor protein 2 (LRP2) is important for development of the embryonic neural crest and brain in both mice and humans. Although a role in cardiovascular development can be expected, the hearts of Lrp2 knockout (KO) mice have not yet been investigated. We studied the cardiovascular development of Lrp2 KO mice between embryonic day 10.5 (E10.5) and E15.5, applying morphometry and immunohistochemistry, using antibodies against Tfap2α (neural crest cells), Nkx2.5 (second heart field), WT1 (epicardium derived cells), tropomyosin (myocardium) and LRP2. The Lrp2 KO mice display a range of severe cardiovascular abnormalities, including aortic arch anomalies, common arterial trunk (persistent truncus arteriosus) with coronary artery anomalies, ventricular septal defects, overriding of the tricuspid valve and marked thinning of the ventricular myocardium. Both the neural crest cells and second heart field, which are essential for the lengthening and growth of the right ventricular outflow tract, are abnormally positioned in the Lrp2 KO. This explains the absence of the aorto-pulmonary septum, which leads to common arterial trunk and ventricular septal defects. Severe blebbing of the epicardial cells covering the ventricles is seen. Epithelial-mesenchymal transition does occur; however, there are fewer WT1-positive epicardium-derived cells in the ventricular wall as compared to normal, coinciding with the myocardial thinning and deep intertrabecular spaces. LRP2 plays a crucial role in cardiovascular development in mice. This corroborates findings of cardiac anomalies in humans with LRP2 mutations. Future studies should reveal the underlying signaling mechanisms in which LRP2 is involved during cardiogenesis. PMID:26822476

  8. Cesarean section in a patient with non-compaction cardiomyopathy managed with ECMO.

    PubMed

    Koster, A A; Pappalardo, F; Silvetti, S; Schirmer, U; Lueth, J U; Dummler, R; Emmerich, M; Schmitt, M; Kirchne, G; Kececioglu, D; Sandica, E

    2013-01-01

    Isolated ventricular non-compaction is a rare cardiomyopathy associated with left heart failure, severe arrhythmias and thromboembolism. We report about our interdisciplinary strategy in a patient with severe isolated ventricular non-compaction cardiomyopathy scheduled for caesarean section in general anaesthesia. Monitoring included placement of an arterial line, a central venous catheter and a pulmonary artery catheter with pacing option. Small introducer gates were placed in the femoral artery and vein to facilitate quick percutaneous institution of extracorporeal life support via extracorporeal membrane oxygenation in case of acute cardiac failure refractory to medical treatment. Inotropic pharmacological therapy with 3 µg/kg/min dobutamine and 0.25 mg/kg/min milrinone was started before surgery. Induction of general anesthesia and rapid sequence intubation was performed with an analgesic dose of 0.5 mg/kg S ketamine, 0.25 mg/kg etomidate and 5 mg rocoronium followed by 1.5 mg/kg succinylcholine. This regimen provided completely stable hemodynamics in this critical period until delivery of the child and continuation of anaesthesia with continuous infusion of propofol and remifentanyl. The current strategies, particularly the preparation for femoro-femoral extracorporeal membrane oxygenation, may be considered in similar cases with a high risk of acute cardiac decompensation which may be refractory to medical treatment. Anaesthesiologist involved in performing caesarean section in women with complex cardiac disease, should encompass extracorporeal membrane oxygenation standby in management of the perioperative period.

  9. Noncompaction Cardiomyopathy with Charcot-Marie-Tooth Disease.

    PubMed

    Eltawansy, Sherif Ali; Bakos, Andrea; Checton, John

    2015-01-01

    We report a case of a 53-year-old female presenting with a new-onset heart failure that was contributed secondary to noncompaction cardiomyopathy. The diagnosis was made by echocardiogram and confirmed by cardiac MRI. Noncompaction cardiomyopathy (also known as ventricular hypertrabeculation) is a newly discovered disease. It is considered to be congenital (genetic) cardiomyopathy. It is usually associated with genetic disorders and that could explain the genetic pathogenesis of the non-compaction cardiomyopathy. Our case had a history of Charcot-Marie-Tooth disease. There is a high incidence of arrhythmia and embolic complications. The treatment usually consists of the medical management, defibrillator placement, and lifelong anticoagulation. Heart transplantation will be the last resort.

  10. Acquired Fontan paradox in isolated right ventricular cardiomyopathy

    PubMed Central

    Saran, Mahim; Sivasubramonian, Sivasankaran; Abhilash, Sreevilasam P; Tharakan, Jaganmohan A

    2016-01-01

    A 44-year-old woman presented with features of congestive heart failure. Echocardiography revealed severe right ventricular dysfunction along with passive minimally pulsatile pulmonary blood flow suggesting very high systemic venous pressures. This was confirmed with cardiac catheterization in which the pressures of superior vena cava and inferior vena cava (19 mmHg) were higher than the pulmonary artery pressures (17 mmHg). Elevation of systemic venous pressures above the pulmonary venous pressures, Fontan paradox, to drive the forward flow, is a specific feature of artificially created cavopulmonary shunts. Late stage of isolated right ventricular cardiomyopathy resulted in the spontaneous evolution of Fontan circulation with a nonfunctional right ventricle in this patient. PMID:27625525

  11. Dual Endothelin Receptor Blockade Abrogates Right Ventricular Remodeling and Biventricular Fibrosis in Isolated Elevated Right Ventricular Afterload

    PubMed Central

    Nielsen, Eva Amalie; Sun, Mei; Honjo, Osami; Hjortdal, Vibeke E.; Redington, Andrew N.; Friedberg, Mark K.

    2016-01-01

    Background Pulmonary arterial hypertension is usually fatal due to right ventricular failure and is frequently associated with co-existing left ventricular dysfunction. Endothelin-1 is a powerful pro-fibrotic mediator and vasoconstrictor that is elevated in pulmonary arterial hypertension. Endothelin receptor blockers are commonly used as pulmonary vasodilators, however their effect on biventricular injury, remodeling and function, despite elevated isolated right ventricular afterload is unknown. Methods Elevated right ventricular afterload was induced by progressive pulmonary artery banding. Seven rabbits underwent pulmonary artery banding without macitentan; 13 received pulmonary artery banding + macitentan; and 5 did not undergo inflation of the pulmonary artery band (sham-operated controls). Results: Right and left ventricular collagen content was increased with pulmonary artery banding compared to sham-operated controls and ameliorated by macitentan. Right ventricular fibrosis signaling (connective tissue growth factor and endothelin-1 protein levels); extra-cellular matrix remodeling (matrix-metalloproteinases 2 and 9), apoptosis and apoptosis-related peptides (caspases 3 and 8) were increased with pulmonary artery banding compared with sham-operated controls and decreased with macitentan. Conclusion Isolated right ventricular afterload causes biventricular fibrosis, right ventricular apoptosis and extra cellular matrix remodeling, mediated by up-regulation of endothelin-1 and connective tissue growth factor signaling. These pathological changes are ameliorated by dual endothelin receptor blockade despite persistent elevated right ventricular afterload. PMID:26765263

  12. Isolated Right Ventricular Infarction Mimicking Anterior ST-Segment Elevation

    PubMed Central

    Oktay, Veysel; Coskun, Ugur; Yildiz, Ahmet; Gurmen, Tevfik

    2016-01-01

    Acute coronary syndromes in patients with presence of ST-segment elevation in the anterior precordial leads indicates left anterior descending coronary artery occlusion. However, anterior ST-segment elevation has also been described in right ventricular myocardial infarction and is thought to be due to right coronary artery (RCA) occlusion. We present a rare case of isolated RVMI presenting with anterior ST-segment elevation due to proximal occlusion of a right coronary artery that was treated by primary coronary angioplasty. Primary coronary angioplasty and stenting of this artery was performed resulting in resolution of the chest pain and ST- segment elevation. PMID:27190867

  13. Substrate Ablation of Ventricular Tachycardia: Late Potentials, Scar Dechanneling, Local Abnormal Ventricular Activities, Core Isolation, and Homogenization.

    PubMed

    Briceño, David F; Romero, Jorge; Gianni, Carola; Mohanty, Sanghamitra; Villablanca, Pedro A; Natale, Andrea; Di Biase, Luigi

    2017-03-01

    Ventricular arrhythmias are a frequent cause of mortality in patients with ischemic cardiomyopathy and nonischemic cardiomyopathy. Scar-related reentry represents the most common arrhythmia substrate in patients with recurrent episodes of sustained ventricular tachycardia (VT). Initial mapping of scar-related VT circuits is focused on identifying arrhythmogenic tissue. The substrate-based strategies include targeting late potentials, scar dechanneling, local abnormal ventricular activities, core isolation, and homogenization of the scar. Even though substrate-based strategies for VT ablation have shown promising outcomes for patients with structural heart disease related to ischemic cardiomyopathy, the data are scarce for patients with nonischemic substrates.

  14. Isolated Left Ventricular Apical Hypoplasia with Right Ventricular Outflow Tract Obstruction: A Rare Combination.

    PubMed

    Zhao, Yonghui; Zhang, Jiaying; Zhang, Jing

    2015-09-01

    Isolated left ventricular (LV) apical hypoplasia is a unusual and recently recognized congenital cardiac anomaly. A 19-year-old man was found to have an abnormal ECG and cardiac murmur identified during a routine health check since joining work. His ECG revealed normal sinus rhythm, right-axis deviation, poor R wave progression, and T wave abnormalities. On physical examination, a 2/6~3/6 systolic murmur was heard at the second intercostal space along the left sternal border. Subsequent echocardiography and cardiac magnetic resonance imaging confirmed the LV apical hypoplasia. Of note, we first found that LV apical hypoplasia was accompanied by RV outflow tract obstruction due to exaggerated rightward bulging of the basal-anterior septum during systole. A close follow-up was performed for the development of heart failure, pulmonary hypertension, and potentially tachyarrhythmia.

  15. [Comparative evaluation of left ventricular function by two-dimensional echocardiography and three-dimensional speckle-tracking echocardiography in noncompaction cardiomyopathy. Results from the MAGYAR-Path Study].

    PubMed

    Kalapos, Anita; Domsik, Péter; Forster, Tamás; Nemes, Attila

    2013-08-25

    Bevezetés: A noncompaction cardiomyopathia a myocardium kompaktálódásának hiányában kialakuló kórkép, amely a bal kamra diszfunkciójával jár együtt. Célkitűzés: Jelen tanulmány célja a balkamra-diszfunkció összehasonlító vizsgálata volt kétdimenziós echokardiográfia és háromdimenziós speckle-tracking echokardiográfia során noncompaction cardiomyopathiában. Módszer: Jelen tanulmányban hét, noncompaction cardiomyopathiában szenvedő beteget (62,9±8,5 év, három férfi) és 10, korban és nemben egyeztetett kontrollesetet (60,7±7,7 év, két férfi) vizsgáltak kétdimenziós echokardiográfia és háromdimenziós speckle-tracking echokardiográfia során a bal kamra funkciójának vizsgálata céljából. Eredmények: Emelkedett bal kamrai végdiasztolés és végszisztolés térfogatértékek, valamint csökkent bal kamrai ejekciós frakció volt igazolható noncompaction cardiomyopathia fennállása esetén. Valamennyi háromdimenziós speckle-tracking echokardiográfia során számított strainparaméter csökkentnek bizonyult noncompaction cardiomyopathia esetén a kontrollokhoz képest. A háromdimenziós speckle-tracking echokardiográfia során mért rotációs paraméterek a bal kamra apicalis és basalis szegmentumainak egyirányú mozgását („rigid body rotation”) igazolták noncompaction cardiomyopathiában. Következtetések: A bal kamra funkciója és szegmentumainak kontraktilitása lényegesen beszűkült noncompaction cardiomyopathiában. A bal kamrai csavarodás (twist) noncompaction cardiomyopathia fennállása esetén hiányzik. Orv. Hetil., 2013, 154, 1352–1359.

  16. Isolated right ventricular infarct presenting as ventricular fibrillation arrest and confirmed by delayed-enhancement cardiac MRI.

    PubMed

    Cavalcante, João L; Al-Mallah, Mouaz; Hudson, Michael

    2010-10-01

    Malignant ventricular arrhythmias resulting from isolated right ventricular myocardial infarction (RVMI) without left ventricular myocardial ischaemia or infarction occur rarely. We present a case of a 61 year-old male with acute onset of chest pain and ventricular fibrillation cardiac arrest requiring prompt defibrillation. Subsequent 15-lead EKG, showed ST-segment elevation in the anterior and right precordial leads without ST-segment elevation in the inferior leads. Angiography documented occlusion of a large RV marginal branch. Delayed enhancement cardiac magnetic resonance imaging (DE-CMR) with gadolinium performed two days post-infarct showed isolated RVMI. Patient remained symptom free and haemodynamically stable throughout his hospital stay. The clinical presentation of isolated RV infarct can be misleading and diagnosis difficult. EKG findings can resemble acute anterior wall myocardial infarction, while its course can be accompanied by life-threatening ventricular arrhythmias. This case uniquely combines this rare clinical sequence with DE-CMR images using gadolinium to confirm isolated RVMI. A brief review of RVMI presentation and associated EKG patterns is also discussed. Published by Elsevier B.V.

  17. Diagnosis and definition of biventricular non-compaction associated to Ebstein's anomaly.

    PubMed

    Fazio, Giovanni; Visconti, Claudia; D'angelo, Luciana; Grassedonio, Emanuele; Lo Re, Giuseppe; D'Amico, Teresa; Sutera, Loredana; Novo, Giuseppina; Ferrara, Filippo; Midiri, Massimo; Novo, Salvatore

    2011-07-01

    Non-compaction of ventricular myocardium is a rare congenital cardiomyopathy characterized by the presence of an extremely thickened endocardial layer with prominent trabeculations and deep recesses in communication with ventricular chamber and determining the typical spongeous aspect. The diagnosis of non-compaction of ventricular myocardium is possible through the identification of morphological alterations by echocardiographic evaluation. Ebstein's anomaly is a rare congenital cardiac disease, defined as the significant apical displacement of the part of the tricuspid valve causing significant tricuspid regurgitation and reduction of the functional right ventricle, right atrial and right ventricular dilatation and atrial and ventricular arrhythmias. We present a case of biventricular non-compaction and Ebstein's anomaly in a 29-year-old Italian man that was referred for chest pain. Diagnosis of Ebstein's anomaly was made during a medical control for military service through an echocardiographic evaluation which left the suspicion of myocardium non-compaction. We present the cardiac image of the 2D and 3D eco, RMN, scintigraphy and ventriculaography. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  18. A novel association of biventricular cardiac noncompaction and diabetic embryopathy: case report and review of the literature.

    PubMed

    Woo, Jennifer S; Perez-Rosendahl, Mari; Haydel, Dana; Perens, Gregory; Fishbein, Michael C

    2015-01-01

    Diabetic embryopathy refers to a constellation of congenital malformations arising in the setting of poorly controlled maternal diabetes mellitus. Cardiac abnormalities are the most frequently observed findings, with a 5-fold risk over normal pregnancies. Although a diverse spectrum of cardiac defects has been documented, cardiac noncompaction morphology has not been associated with this syndrome. In this report, we describe a novel case of biventricular cardiac noncompaction in a neonate of a diabetic mother. The patient was a late preterm female with right anotia, caudal dysgenesis, multiple cardiac septal and aortic arch defects, and biventricular cardiac noncompaction. Examination of both ventricles demonstrated spongy myocardium with increased myocardial trabeculation greater than 50% left ventricular thickness and greater than 75% right ventricular thickness, with hypoplasia of the bilateral papillary muscles, consistent with noncompaction morphology. Review of the literature highlights the importance of gene expression and epigenomic regulation in cardiac embryogenesis.

  19. [Successful outcome of a pregnancy with an extremely low fetal heart rate (34 bpm) due to isolated complete heart block--case report].

    PubMed

    Hamela-Olkowska, Anita; Dangel, Joanna; Miszczak-Knecht, Maria

    2009-09-01

    Isolated complete congenital heart block (CHB) in the majority of cases is associated with the presence of autoantibodies to SSA (Ro) and SSB (La) antigens in the maternal serum. The prognosis is less favorable in fetuses with a ventricular rate < 55bpm. We have reported a case of a fetus with an isolated non-autoimmune CHB with an extremely low ventricular rate (34bpm) in which the outcome was favorable. In the neonate the non-compaction of the myocardium was diagnosed.

  20. Modulation of ventricular fibrillation in isolated perfused heart by dofetilide.

    PubMed

    Amitzur, Giora; Shenkar, Nitza; Leor, Jonathan; Novikov, Ilia; Eldar, Michael

    2003-06-01

    The authors studied the involvement of IKr potassium current in ventricular fibrillation during perfusion. Electrophysiologic parameters were measured before and after dofetilide administration (2.5, 7.5, and 12.5 x 10-7 M, n = 8) in isolated perfused feline hearts. During pacing, these parameters included epicardial conduction time, refractoriness, and the fastest rate for 1:1 pacing/response capture. During 8 minutes of electrically induced tachyarrhythmias, they included heart rate and normalized entropy reflecting the degree of organization. In all groups, arrhythmia rate was slower in the right ventricle than in the left ventricle. Dofetilide decreased the arrhythmia rate more than it increased organization, reduced its maintenance, or increased difficulty in initiation. Refractoriness was prolonged in a reverse use-dependent way which was less than 1:1 pacing/response capture. Unexpectedly, a moderate prolongation of conduction time was observed. Inverse correlation was found between the arrhythmia rate and changes in refractoriness and conduction time and between the degree of organization and refractoriness (both ventricles) and conduction time (right ventricle). Dofetilide, which intensively blocks IKr current and unexpectedly suppressed conduction, has different quantitative effects on fibrillation features. These changes in fibrillation suggest that these effects are mainly associated with refractoriness prolongation and do not seem to be attenuated by conduction suppression.

  1. Naturally Occurring Biventricular Noncompaction in an Adult Domestic Cat.

    PubMed

    Kittleson, M D; Fox, P R; Basso, C; Thiene, G

    2017-03-01

    A definitively diagnosed case of left ventricular noncompaction (LVNC) has not been previously reported in a non-human species. We describe a Maine Coon cross cat with echocardiographically and pathologically documented LVNC. The cat was from a research colony and was heterozygous for the cardiac myosin binding protein C mutation associated with hypertrophic cardiomyopathy (HCM) in Maine Coon cats (A31P). The cat had had echocardiographic examinations performed every 6 months until 6 years of age at which time the cat died of an unrelated cause. Echocardiographic findings consistent with LVNC (moth-eaten appearance to the inner wall of the mid- to apical region of the left ventricle (LV) in cross section and trabeculations of the inner LV wall that communicated with the LV chamber) first were identified at 2 years of age. At necropsy, pathologic findings of LVNC were verified and included the presence of noncompacted myocardium that consisted of endothelial-lined trabeculations and sinusoids that constituted more than half of the inner part of the LV wall. The right ventricular (RV) wall also was affected. Histopathology identified myofiber disarray, which is characteristic of HCM, although heart weight was normal and LV wall thickness was not increased.

  2. Isolated right ventricular cardiomyopathy with autoimmune hypothyroidism: a rare association in an adolescent

    PubMed Central

    Yelve, Kavita; Panandikar, Gajanan Ashok; Pazare, Amar; Bajpai, Smrati

    2015-01-01

    A 13-year-old girl presented with progressive dyspnoea and palpitation, diagnosed on echocardiography as primary right ventricular cardiomyopathy with atrial fibrillation. Her thyroid profile was positive for antithyroid microsomal antibody, and antithyroid peroxidase antibodies were suggestive of autoimmune hypothyroidism. She was managed with furosemide, digoxin, acenocoumarol and thyroxine following which she showed significant improvement. This is a rare case of isolated right ventricular cardiomyopathy and its association with autoimmune hypothyroidism presenting at the age of 13. PMID:25795745

  3. Pathologic features of dilated cardiomyopathy with localized noncompaction in a child with deletion 1p36 syndrome.

    PubMed

    Pearce, F Bennett; Litovsky, Silvio H; Dabal, Robert J; Robin, Nathaniel; Dure, Leon J; George, James F; Kirklin, James K

    2012-01-01

    Dilated cardiomyopathy and ventricular noncompaction have been reported in association with deletion 1p36 syndrome. Previous descriptions include echocardiographic and/or gross pathologic descriptions. There are no previous reports of microscopic findings. We report a case with descriptions of echocardiographic, gross pathologic, and microscopic findings.

  4. Isolated right ventricular infiltrating tumour: metastatic hepatocellular carcinoma.

    PubMed

    Lee, Wei-Chieh; Fu, Morgan; Liu, Wen-Hao

    2015-10-01

    Hepatocellular carcinoma (HCC) with intracavitary metastasis to the heart is rare. The incidence of HCC with right atrial metastasis is less than 6% at autopsy. Reports of HCC with right ventricular metastasis without inferior vena cava and right atrial metastasis are rarer. The diagnosis of metastasis of HCC into the cardiac cavity might be overlooked because the symptoms are neither apparent nor specific. Here, we report a patient with metastasis of HCC into the right ventricle cavity. The patient was in a disease-free status and experienced lower limbs oedema and gradual shortness of breath.

  5. Behavior of noncompacted high strength bolted joints

    NASA Astrophysics Data System (ADS)

    Huckelbridge, A. A., Jr.; Miller, C. J.; Burkhart, R. A.; Asante, K.

    1980-03-01

    All tests were continued until failure of the joint; all joints were of a butt type utilizing double lap plates and 3/4 inch A325 high strength bolts. Noncompaction ranged from the fully compacted state up to 1/8 inch difference in thickness of connected plates. Noncompaction was observed to significantly reduce the load level at which joints slip into bearing. Ultimate static loads were not affected by noncompaction, however. Under repeated loads the joints tended to slip into bearing even though nominally designed as friction connections. Fatigue failures were observed to occur through the minimum net section, usually, though not always, in the lap plates. The greatest reduction in slip load was in the shorter non-compacted joints; those with two or three bolts/row only. It is recommended that non-compaction be accounted for in these types of joints if it is necessary to maintain a friction-type connection. Non-compaction would not seem to be significant for bearing type connections.

  6. Action potential conduction between a ventricular cell model and an isolated ventricular cell.

    PubMed Central

    Wilders, R; Kumar, R; Joyner, R W; Jongsma, H J; Verheijck, E E; Golod, D; van Ginneken, A C; Goolsby, W N

    1996-01-01

    We used the Luo and Rudy (LR) mathematical model of the guinea pig ventricular cell coupled to experimentally recorded guinea pig ventricular cells to investigate the effects of geometrical asymmetry on action potential propagation. The overall correspondence of the LR cell model with the recorded real cell action potentials was quite good, and the strength-duration curves for the real cells and for the LR model cell were in general correspondence. The experimental protocol allowed us to modify the effective size of either the simulation model or the real cell. 1) When we normalized real cell size to LR model cell size, required conductance for propagation between model cell and real cell was greater than that found for conduction between two LR model cells (5.4 nS), with a greater disparity when we stimulated the LR model cell (8.3 +/- 0.6 nS) than when we stimulated the real cell (7.0 +/- 0.2 nS). 2) Electrical loading of the action potential waveform was greater for real cell than for LR model cell even when real cell size was normalized to be equal to that of LR model cell. 3) When the size of the follower cell was doubled, required conductance for propagation was dramatically increased; but this increase was greatest for conduction from real cell to LR model cell, less for conduction from LR model cell to real cell, and least for conduction from LR model cell to LR model cell. The introduction of this "model clamp" technique allows testing of proposed membrane models of cardiac cells in terms of their source-sink behavior under conditions of extreme coupling by examining the symmetry of conduction of a cell pair composed of a model cell and a real cardiac cell. We have focused our experimental work with this technique on situations of extreme uncoupling that can lead to conduction block. In addition, the analysis of the geometrical factors that determine success or failure of conduction is important in the understanding of the process of discontinuous

  7. Prognostic impact of isolated right ventricular dysfunction in sepsis and septic shock: an 8-year historical cohort study.

    PubMed

    Vallabhajosyula, Saraschandra; Kumar, Mukesh; Pandompatam, Govind; Sakhuja, Ankit; Kashyap, Rahul; Kashani, Kianoush; Gajic, Ognjen; Geske, Jeffrey B; Jentzer, Jacob C

    2017-09-07

    Echocardiographic myocardial dysfunction is reported commonly in sepsis and septic shock, but there are limited data on sepsis-related right ventricular dysfunction. This study sought to evaluate the association of right ventricular dysfunction with clinical outcomes in patients with severe sepsis and septic shock. Historical cohort study of adult patients admitted to all intensive care units at the Mayo Clinic from January 1, 2007 through December 31, 2014 for severe sepsis and septic shock, who had an echocardiogram performed within 72 h of admission. Patients with prior heart failure, cor-pulmonale, pulmonary hypertension and valvular disease were excluded. Right ventricular dysfunction was defined by the American Society of Echocardiography criteria. Outcomes included 1-year survival, in-hospital mortality and length of stay. Right ventricular dysfunction was present in 214 (55%) of 388 patients who met the inclusion criteria-isolated right ventricular dysfunction was seen in 100 (47%) and combined right and left ventricular dysfunction in 114 (53%). The baseline characteristics were similar between cohorts except for the higher mechanical ventilation use in patients with isolated right ventricular dysfunction. Echocardiographic findings demonstrated lower right ventricular and tricuspid valve velocities in patients with right ventricular dysfunction and lower left ventricular ejection fraction and increased mitral E/e' ratios in patients with combined right and left ventricular dysfunction. After adjustment for age, comorbidity, illness severity, septic shock and use of mechanical ventilation, isolated right ventricular dysfunction was independently associated with worse 1-year survival-hazard ratio 1.6 [95% confidence interval 1.2-2.1; p = 0.002) in patients with sepsis and septic shock. Isolated right ventricular dysfunction is seen commonly in sepsis and septic shock and is associated with worse long-term survival.

  8. Spontaneous closure of isolated ventricular septal defect in the pika (Ochotona rufescens rufescens).

    PubMed

    Shinohara, H; Nishimura, H

    1986-04-01

    The incidence of spontaneously occurring ventricular septal defects (VSD) in PIKA neonates and its fate during development are investigated. A total of 160 PIKAs were used in the present study. They consisted of three groups; first, 56 live neonates, second, 37 3-week-old live animals and third, 68 animals which had died during the first two weeks after birth from unknown causes. As high as 8.9% (5 cases out of 56) of the live neonates revealed isolated ventricular septal defects of membranous type. Decreased incidence (2.7%) was seen in 3-week-old PIKAs. Its implication and significance are evaluated in the discussion.

  9. Sustained vortex-like waves in normal isolated ventricular muscle.

    PubMed Central

    Davidenko, J M; Kent, P F; Chialvo, D R; Michaels, D C; Jalife, J

    1990-01-01

    Sustained reentrant excitation may be initiated in small (20 x 20 x less than 0.6 mm) preparations of normal ventricular muscle. A single appropriately timed premature electrical stimulus applied perpendicularly to the wake of a propagating quasiplanar wavefront gives rise to circulation of self-sustaining excitation waves, which pivot at high frequency (5-7 Hz) around a relatively small "phaseless" region. Such a region develops only very low amplitude depolarizations. Once initiated, most episodes of reentrant activity last indefinitely but can be interrupted by the application of an appropriately timed electrical stimulus. The entire course of the electrical activity is visualized with high temporal and spatial resolution, as well as high signal-to-noise ratio, using voltage-sensitive dyes and optical mapping. Two- and three-dimensional graphics of the fluorescence changes recorded by a 10 x 10 photodiode array from a surface of 12 x 12 mm provide sequential images (every msec) of voltage distribution during a reentrant vortex. The results suggest that two-dimensional vortex-like reentry in cardiac muscle is analogous to spiral waves in other biological and chemical excitable media. Images PMID:2247448

  10. Calcium current in isolated neonatal rat ventricular myocytes.

    PubMed Central

    Cohen, N M; Lederer, W J

    1987-01-01

    1. Calcium currents (ICa) from neonatal rat ventricular heart muscle cells grown in primary culture were examined using the 'whole-cell' voltage-clamp technique (Hamill, Marty, Neher, Sakmann & Sigworth, 1981). Examination of ICa was limited to one calcium channel type, 'L' type (Nilius, Hess, Lansman & Tsien, 1985), by appropriate voltage protocols. 2. We measured transient and steady-state components of ICa, and could generally describe ICa in terms of the steady-state activation (d infinity) and inactivation (f infinity) parameters. 3. We observed that the reduction of ICa by the calcium channel antagonist D600 can be explained by both a shift of d infinity to more positive potentials as well as a slight reduction of ICa conductance. D600 did not significantly alter either the rate of inactivation of ICa or the voltage dependence of f infinity. 4. The calcium channel modulator BAY K8644 shifted both d infinity and f infinity to more negative potentials. Additionally, BAY K8644 increased the rate of inactivation at potentials between +5 and +55 mV. Furthermore, BAY K8644 also increased ICa conductance, a change consistent with a promotion of 'mode 2' calcium channel activity (Hess, Lansman & Tsien, 1984). 5. We conclude that, as predicted by d infinity and f infinity, there is a significant steady-state component of ICa ('window current') at plateau potentials in neonatal rat heart cells. Modulation of the steady-state and transient components of ICa by various agents can be attributed both to specific alterations in d infinity and f infinity and to more complicated alterations in the mode of calcium channel activity. PMID:2451004

  11. [Serial assessment of left ventricular function after valve replacement for isolated aortic regurgitation].

    PubMed

    Misawa, Y; Hasegawa, T; Kato, M; Horimi, H; Yamaguchi, T

    1991-04-01

    Between 1978 and 1990, serial echocardiographic studies were performed on consecutive twenty-five patients of isolated aortic regurgitation (AR) before and after aortic valve replacement (AVR). The mean follow up period was 55 +/- 30 months. The serial changes in left ventricular end-diastolic dimension (LVDd), left ventricular end-systolic dimension (LVDs), fractional shortening (FS), and ejection fraction (EF) were assessed. According to preoperative echocardiographic studies, 25 patients were divided into two groups: Group I with LVDs greater than 50 mm and FS less than 25%, Group II with LVDs less than or equal to 50 mm and/or FS greater than or equal to 25%. One year after AVR, echocardiographic studies revealed normalization of LVDd and LVDs in Group II, and persistent left ventricular enlargement with lower FS and EF levels in Group I. However three years after AVR, LVDd, LVDs, and FS and EF of Group I returned to normal levels. It was concluded that in order to normalize the left ventricular function in isolated AR patients, those who had LVDs greater than 50 mm and FS less than 25% required three years after AVR, those patients who had LVDs less than or equal to 50 mm and/or FS greater than or equal to 25%, required only one year after AVR.

  12. [Hypervolemic redistribution mechanism in pulmonary edema in patients with isolated left ventricular failure].

    PubMed

    Shteĭngardt, Iu N; Inzel', T N

    1981-04-01

    The authors examined 90 patients with ischemic heart disease and isolated left-ventricular insufficiency by impedance plethysmography and determined the body total water content by means of tritium oxide in 32 of them. It was established that there is no essential increase in total body water and volumes of circulating blood and plasma at the peak of manifestations of isolated left-ventricular insufficiency. The redistribution of some of the blood from the periphery of systemic circulation to the center, mainly into the pulmonary circulation, possibly plays the principle role in the genesis of pulmonary circulation hypervolemia and pulmonary edema in approximately half of the cases. The same mechanism with its reverse direction occurs in successful treatment and correction of hypervolemia of pulmonary circulation and pulmonary edema.

  13. Model building with non-compact cosets

    NASA Astrophysics Data System (ADS)

    Croon, Djuna Lize

    2016-11-01

    We explore Goldstone boson potentials in non-compact cosets of the form SO (n , 1) / SO (n). We employ a geometric approach to find the scalar potential, and focus on the conditions under which it is compact in the large field limit. We show that such a potential is found for a specific misalignment of the vacuum. This result has applications in different contexts, such as in Composite Higgs scenarios and theories for the Early Universe. We work out an example of inflation based on a non-compact coset which makes predictions which are consistent with the current observational data.

  14. Congenital isolated cleft mitral valve leaflet and apical muscular ventricular septal defect in a Holstein calf.

    PubMed

    Depenbrock, Sarah M; Visser, Lance C; Kohnken, Rebecca A; Russell, Duncan S; Simpson, Katharine M; Bonagura, John D

    2015-09-01

    A 5-week-old Holstein heifer calf presented for emergency treatment of signs referable to gastrointestinal disease and hypovolemic shock. Fluid resuscitation uncovered clinical signs of primary cardiac disease and echocardiography revealed multiple congenital cardiac defects. Malformations included a cleft anterior mitral valve leaflet resembling an isolated cleft mitral valve and an apically-located muscular ventricular septal defect. The echocardiographic and postmortem findings associated with these defects are presented and discussed in this report.

  15. Chamber-specific effects of hypokalaemia on ventricular arrhythmogenicity in isolated, perfused guinea-pig heart.

    PubMed

    Osadchii, Oleg E; Bentzen, Bo Hjorth; Olesen, Soren Peter

    2009-04-01

    Diuretic-induced hypokalaemia has been shown to promote cardiac arrhythmias in hypertensive patients. The present study was designed to determine whether hypokalaemia increases arrhythmic susceptibility of the left ventricle (LV) or the right ventricle (RV), or both. Proarrhythmic effects of hypokalaemic perfusion (2.5 mm K(+) for 30 min) were assessed in isolated guinea-pig heart preparations using simultaneous recordings of volume-conducted electrocardiogram and monophasic action potentials from six ventricular epicardial sites. Effective refractory periods, ventricular fibrillation thresholds and inducibility of tachyarrhythmias by programmed electrical stimulation and tachypacing were determined at the LV and the RV epicardial stimulation sites. Hypokalaemia promoted spontaneous ventricular ectopic activity, an effect attributed to non-uniform prolongation of ventricular repolarization resulting in increased RV-to-LV transepicardial dispersion of refractoriness and action potential duration. Furthermore, hypokalaemic perfusion was associated with reduced ventricular fibrillation threshold and increased inducibility of tachyarrhythmias by programmed electrical stimulation and tachypacing as determined at the LV stimulation site. In contrast, the RV stimulation revealed no change in arrhythmic susceptibility of the RV chamber. Consistently, hypokalaemia reduced the LV effective refractory period but had no effect on the RV refractoriness. This change enabled generation of premature propagating responses by extrastimulus application at earlier time points during LV repolarization. Increased prematurity of extrastimulus-evoked propagating responses was associated with exaggerated local inhomogeneities in intraventricular conduction and action potential duration in hypokalaemic LV, thus creating a favourable stage for re-entrant tachyarrhythmias. Taken together, these findings suggest that proarrhythmic effects of hypokalaemia are mostly attributed to increased LV

  16. Successful heart failure therapy in mitochondrial disorder with noncompaction cardiomyopathy.

    PubMed

    Finsterer, Josef; Josef, Finsterer; Stöllberger, Claudia; Claudia, Stöllberger; Gelpi, Ellen; Ellen, Gelpi

    2006-01-01

    Effective heart failure therapy with angiotensin-converting enzyme inhibitors and beta-blockers in a patient with mitochondrial disorder and asymptomatic previously stable hypertrophic cardiomyopathy and left ventricular noncompaction (NCCMP) has not been reported. In a 58-year-old male with juvenile seizures, impaired hearing, recurrent pancreatitis, diabetes, recurrent emesis and diarrhea, discrete weakness for hip flexion, general wasting, and reduced tendon reflexes, elevated muscle-enzymes, abnormal lactate-stress-test, and mitochondrial dysfunction on muscle biopsy, mitochondrial disorder was diagnosed at age 51 year. Echocardiography revealed myocardial thickening and NCCMP. Cardiac abnormalities did not progress upon repeated follow-ups. At age 57 year he developed acute heart failure during respiratory infection. Echocardiography additionally revealed reduced left ventricular systolic function, and a restrictive filling pattern. Within seven weeks of therapy with ramipril (2.5 mg/day) and bisoprolol (1.25 mg/day) the restrictive filling pattern disappeared and fractional shortening normalized. This case shows that heart failure in a patient with mitochondrial disorder and previously stable hypertrophic cardiomyopathy and NCCMP promptly resolves under therapy with angiotensin-converting enzyme inhibitors and beta-blockers.

  17. Prenatal Isolated Ventricular Septal Defect May Not Be Associated with Trisomy 21.

    PubMed

    Shen, Ori; Lieberman, Sari; Farber, Benjamin; Terner, Daniel; Lahad, Amnon; Levy-Lahad, Ephrat

    2014-04-23

    The aim of this study was to examine if isolated fetal ventricular septal defect (VSD) is associated with trisomy 21. One hundred twenty six cases with prenatal VSD diagnosed by a pediatric cardiologist were reviewed. Cases with known risk factors for congenital heart disease, the presence of other major anomalies, soft signs for trisomy 21 or a positive screen test for trisomy 21 were excluded. Ninety two cases formed the study group. None of the cases in the study group had trisomy 21. The upper limit of prevalence for trisomy 21 in isolated VSD is 3%. When prenatal VSD is not associated with other major anomalies, soft markers for trisomy 21 or a positive nuchal translucency or biochemical screen, a decision whether to perform genetic amniocentesis should be individualized. The currently unknown association between isolated VSD and microdeletions and microduplications should be considered when discussing this option.

  18. Effects of an Isolated Complete Right Bundle Branch Block on Mechanical Ventricular Function.

    PubMed

    Zhang, Qin; Xue, Minghua; Li, Zhan; Wang, Haiyan; Zhu, Lei; Liu, Xinling; Meng, Haiyan; Hou, Yinglong

    2015-12-01

    The purpose of this study was to investigate the effects of an isolated complete right bundle branch block on mechanical ventricular function. Two groups of participants were enrolled in this study: a block group, consisting of 98 patients with isolated complete right bundle branch blocks without structural heart disease, and a control group, consisting of 92 healthy adults. The diameter, end-diastolic area, end-systolic area, and right ventricular (RV) fractional area change were obtained to evaluate morphologic and systolic function by 2-dimensional sonographic technology. Systolic and diastolic velocities and time interval parameters were measured to assess mechanical ventricular performance using pulsed wave tissue Doppler imaging. Although there was no significant difference in the RV fractional area change between the patients with blocks and controls, the diameter, end-diastolic area, and end-systolic area of the RV were significantly larger in the patients with blocks (P < .05). In the patients with blocks, the peak velocities during systole and early diastole and the ratio of the peak velocities during early and late diastole decreased. The block group had a prolonged pre-ejection period, electromechanical delay time, and isovolumic relaxation time, a decreased ejection time, and an increased pre-ejection period/ejection time ratio, and the myocardial performance index (Tei index) at the basal RV lateral wall was significantly increased. There were no significant differences in any echocardiographic parameters at different sites of the left ventricle. In patients with isolated complete right bundle branch blocks, systolic and diastolic functions are impaired in the RV, and follow-up is needed. © 2015 by the American Institute of Ultrasound in Medicine.

  19. A novel anionic conductance affects action potential duration in isolated rat ventricular myocytes.

    PubMed

    Spencer, C I; Uchida, W; Kozlowski, R Z

    2000-01-01

    Effects of extracellular anions were studied in electrophysiological experiments on freshly isolated rat ventricular myocytes. Under current-clamp, action potential duration (APD) was prolonged by reducing the extracellular Cl(-) concentration and shortened by replacement of extracellular Cl(-) with I(-). Under voltage-clamp, membrane potential steps or ramps evoked an anionic background current (I(AB)) carried by either Cl(-), Br(-), I(-) or NO(3)(-). Activation of I(AB) was Ca(2+)- and cyclic AMP-independent, and was unaffected by cell shrinkage. I(AB) was insensitive to stilbene and fenamate anion transport blockers at concentrations that inhibit Ca(2+)-, cyclic AMP- and swelling-activated Cl(-) currents in ventricular cells of other mammals. These results suggest that I(AB) may be carried by a novel class of Cl(-) channel. Correlation of anion substitution experiments on membrane current and action potentials revealed that I(AB) could play a major role in controlling rat ventricular APD. These findings have important implications for those studying cardiac Cl(-) channels as potential targets for novel antiarrythmic agents.

  20. Infinitely many singular interactions on noncompact manifolds

    SciTech Connect

    Kaynak, Burak Tevfik Turgut, O. Teoman

    2015-05-15

    We show that the ground state energy is bounded from below when there are infinitely many attractive delta function potentials placed in arbitrary locations, while all being separated at least by a minimum distance, on two dimensional non-compact manifold. To facilitate the reading of the paper, we first present the arguments in the setting of Cartan–Hadamard manifolds and then subsequently discuss the general case. For this purpose, we employ the heat kernel techniques as well as some comparison theorems of Riemannian geometry, thus generalizing the arguments in the flat case following the approach presented in Albeverio et al. (2004). - Highlights: • Schrödinger-operator for infinitely many singular interactions on noncompact manifolds. • Proof of the finiteness of the ground-state energy.

  1. Core isolation of critical arrhythmia elements for treatment of multiple scar-based ventricular tachycardias.

    PubMed

    Tzou, Wendy S; Frankel, David S; Hegeman, Timothy; Supple, Gregory E; Garcia, Fermin C; Santangeli, Pasquale; Katz, David F; Sauer, William H; Marchlinski, Francis E

    2015-04-01

    Radiofrequency ablation of multiple or unmappable ventricular tachycardias (VTs) remains a challenge with unclear end points. We present our experience with a new strategy isolating core elements of VT circuits. Patients with structural heart disease presenting for VT radiofrequency ablation at 2 centers were included. Strategy involved entrainment/activation mapping if VT was hemodynamically stable, and voltage mapping with electrogram analysis and pacemapping. Core isolation (CI) was performed incorporating putative isthmus and early exit site(s) based on standard criteria. If VT was noninducible, the dense scar (<0.5 mV) region was isolated. Successful CI was defined by exit block (20 mA at 2 ms) within the isolated region. VT inducibility was also assessed. Forty-four patients were included (mean age, 63; 95% male; 73% ischemic cardiomyopathy; mean left ventricular ejection fraction, 31%; 68% with multiple unstable VTs [mean, 3+2]). CI area was 11+12 versus 55+40 cm(2) total scar area. Additional substrate modification was performed in 27 (61%), and epicardial radiofrequency ablation was performed in 4 (9%) patients. CI was achieved in 37 (84%) and led to better VT-free survival (log rank P=0.013). CI is a novel strategy with a discrete and measurable end point beyond VT inducibility to treat patients with multiple or unmappable VTs. The CI region can be selected based on standard characterization of suspected VT isthmus surrogates thus limiting ablation target size. Exit block within the isolated area is achievable in most and may further improve long-term success. © 2015 American Heart Association, Inc.

  2. Epicardial wavefronts arise from widely distributed transient sources during ventricular fibrillation in the isolated swine heart

    NASA Astrophysics Data System (ADS)

    Rogers, J. M.; Walcott, G. P.; Gladden, J. D.; Melnick, S. B.; Ideker, R. E.; Kay, M. W.

    2008-01-01

    It has been proposed that ventricular fibrillation (VF) waves emanate from stable localized sources, often called 'mother rotors'. However, evidence for the existence of these rotors is conflicting. Using a new panoramic optical mapping system that can image nearly the entire ventricular epicardium, we recently excluded epicardial mother rotors as the drivers of Wiggers' stage II VF in the isolated swine heart. Furthermore, we were unable to find evidence that VF requires sustained intramural sources. The present study was designed to test the following hypotheses: (i) VF is driven by a specific region, and (ii) rotors that are long-lived, though not necessarily permanent, are the primary generators of VF wavefronts. Using panoramic optical mapping, we mapped VF wavefronts from six isolated swine hearts. Wavefronts were tracked to characterize their activation pathways and to locate their originating sources. We found that the wavefronts that participate in epicardial re-entry were not confined to a compact region; rather they activated the entire epicardial surface. New wavefronts feeding into the epicardial activation pattern were generated over the majority of the epicardium and almost all of them were associated with rotors or repetitive breakthrough patterns that lasted for less than 2 s. These findings indicate that epicardial wavefronts in this model are generated by many transitory epicardial sources distributed over the entire surface of the heart.

  3. The herbal drug Catuama reverts and prevents ventricular fibrillation in the isolated rabbit heart.

    PubMed

    Pontieri, Vera; Neto, Augusto Scalabrini; de França Camargo, André Ferrari; Koike, Marcia Kiyomi; Velasco, Irineu Tadeu

    2007-01-01

    Catuama, an herbal drug very popular in Brazil, was tested on the reversion and prevention of ventricular fibrillation (VF) in the isolated rabbit heart. Catuama (a mixture of Trichilia catigua, Paullinia cupana, Ptychopetalum olacoides, and Zinziber officinalis) was perfused in the isolated perfused rabbit heart. Its effects on intraventricular conduction, heart rate, and monophasic action potential (MAP) duration were evaluated, and sustained VF was induced. The effects on reversion and reinduction of arrhythmia were observed, and new measures were taken in the hearts that reverted. Catuama and T catigua reverted VF in all hearts, prevented reinduction, and prolonged intraventricular conduction. Catuama prolonged MAP phase 2. On the other hand, P cupana reverted VF in 3 of 5 hearts, but depressed automatism, prolonged MAP phase 3, and did not prevent reinduction. Catuama reverted and prevented VF in this model. T catigua extract is probably the main agent responsible for the beneficial actions observed. Further studies are now in progress to clarify these actions.

  4. Effects of tedisamil (KC-8857) on cardiac electrophysiology and ventricular fibrillation in the rabbit isolated heart.

    PubMed

    Chi, L; Park, J L; Friedrichs, G S; Banglawala, Y A; Perez, M A; Tanhehco, E J; Lucchesi, B R

    1996-03-01

    1. The direct cardiac electrophysiological and antifibrillatory actions of tedisamil (KC-8857) were studied in rabbit isolated hearts. 2. Tedisamil (1, 3, and 10 microM), prolonged the ventricular effective refractory period (VRP) from 120 +/- 18 ms (baseline) to 155 +/- 19, 171 +/- 20, and 205 +/- 14 ms, respectively. Three groups of isolated hearts (n = 6 each) were used to test the antifibrillatory action of tedisamil. Hearts were perfused with 1.25 microM pinacidil, a KATP channel activator. Hearts were subjected to hypoxia for 12 min followed by 40 min of reoxygenation. Ventricular fibrillation (VF) developed during hypoxia and reoxygenation in both the control and 1 microM tedisamil-treated groups (5/6 and 4/6, respectively). Tedisamil (3 microM) reduced the incidence of VF (0/6, P = 0.007 vs. control). 3. In a separate group of hearts, VF was initiated by electrical stimulation. The administration of 0.3 ml of 10 mM tedisamil, via the aortic cannula, terminated VF in all hearts, converting them to normal sinus rhythm. 4. Tedisamil (3 microM) reversed pinacidil-induced negative inotropic effects in rabbit isolated atrial muscle which were equilibrated under normoxia, as well as in atrial muscle subjected to hypoxia and reoxygenation. 5. The results demonstrate a direct antifibrillatory action of tedisamil in vitro. The mechanism responsible for the observed effects may involve modulation by tedisamil of the cardiac ATP-regulated potassium channel, in addition to its antagonism of IK and Ito.

  5. Effects of tedisamil (KC-8857) on cardiac electrophysiology and ventricular fibrillation in the rabbit isolated heart.

    PubMed Central

    Chi, L.; Park, J. L.; Friedrichs, G. S.; Banglawala, Y. A.; Perez, M. A.; Tanhehco, E. J.; Lucchesi, B. R.

    1996-01-01

    1. The direct cardiac electrophysiological and antifibrillatory actions of tedisamil (KC-8857) were studied in rabbit isolated hearts. 2. Tedisamil (1, 3, and 10 microM), prolonged the ventricular effective refractory period (VRP) from 120 +/- 18 ms (baseline) to 155 +/- 19, 171 +/- 20, and 205 +/- 14 ms, respectively. Three groups of isolated hearts (n = 6 each) were used to test the antifibrillatory action of tedisamil. Hearts were perfused with 1.25 microM pinacidil, a KATP channel activator. Hearts were subjected to hypoxia for 12 min followed by 40 min of reoxygenation. Ventricular fibrillation (VF) developed during hypoxia and reoxygenation in both the control and 1 microM tedisamil-treated groups (5/6 and 4/6, respectively). Tedisamil (3 microM) reduced the incidence of VF (0/6, P = 0.007 vs. control). 3. In a separate group of hearts, VF was initiated by electrical stimulation. The administration of 0.3 ml of 10 mM tedisamil, via the aortic cannula, terminated VF in all hearts, converting them to normal sinus rhythm. 4. Tedisamil (3 microM) reversed pinacidil-induced negative inotropic effects in rabbit isolated atrial muscle which were equilibrated under normoxia, as well as in atrial muscle subjected to hypoxia and reoxygenation. 5. The results demonstrate a direct antifibrillatory action of tedisamil in vitro. The mechanism responsible for the observed effects may involve modulation by tedisamil of the cardiac ATP-regulated potassium channel, in addition to its antagonism of IK and Ito. Images Figure 9 PMID:8882624

  6. Panoramic optical mapping reveals continuous epicardial reentry during ventricular fibrillation in the isolated swine heart.

    PubMed

    Rogers, Jack M; Walcott, Gregory P; Gladden, James D; Melnick, Sharon B; Kay, Matthew W

    2007-02-01

    During ventricular fibrillation (VF), activation waves are fragmented and the heart cannot contract synchronously. It has been proposed that VF waves emanate from stable sources ("mother rotors"). Previously, we used new optical mapping technology to image VF wavefronts from nearly the entire epicardial surface of six isolated swine hearts. We found that VF was not driven by epicardial rotors, but could not exclude the presence of stable rotors hidden within the ventricular walls. Here, we use graph theoretic analysis to show that, in all 17 VF episodes we analyzed, it was always possible to trace sequences of wavefronts through series of fragmentation and collision events from the beginning to the end of the episode. The set of wavefronts that were so related (the dominant component) consisted of 92%+/-1% of epicardial wavefronts. Because each such wavefront sequence constitutes a continuous activation front, this finding shows that complete reentrant pathways were always present on the epicardial surface and therefore, that wavefront infusion from nonepicardial sources was not strictly necessary for VF maintenance. These data suggest that VF in this model is not driven by localized sources; thus, new anti-VF treatments designed to target such sources may be less effective than global interventions.

  7. Dynamic sympathetic regulation of left ventricular contractility studied in the isolated canine heart.

    PubMed

    Miyano, H; Nakayama, Y; Shishido, T; Inagaki, M; Kawada, T; Sato, T; Miyashita, H; Sugimachi, M; Alexander, J; Sunagawa, K

    1998-08-01

    We investigated the dynamic sympathetic regulation of left ventricular end-systolic elastance (Ees) using an isolated canine ventricular preparation with functioning sympathetic nerves intact. We estimated the transfer function from both stellate ganglion stimulation to Ees and ganglion stimulation to heart rate (HR) for both left and right ganglia by means of the white noise approach and transformed those transfer functions into corresponding step responses. The HR response was much larger with right sympathetic stimulation than with left sympathetic stimulation (4.3 +/- 1.4 vs. 0.7 +/- 0.6 beats . min-1 . Hz-1, P < 0.01). In contrast, the Ees responses without pacing were not significantly different between left and right sympathetic stimulation (0.72 +/- 0.34 vs. 0.76 +/- 0. 42 mmHg . ml-1 . Hz-1). Fixed-rate pacing significantly decreased the Ees response to right sympathetic stimulation (0.53 +/- 0.43 mmHg . ml-1 . Hz-1, P < 0.01), but not to left sympathetic stimulation (0.67 +/- 0.32 mmHg . ml-1 . Hz-1, not significant). Although the mechanism by which the sympathetic nervous system regulates cardiac contractility is different depending on whether the left or right sympathetic nerves are activated, this difference does not affect the apparent response of Ees to dynamic sympathetic stimulation.

  8. Spaces of embeddings of noncompact manifolds

    NASA Astrophysics Data System (ADS)

    khalil, Assakta; Ahmad, Abd Ghafur Bin

    2017-04-01

    Let M signifies smooth, non-compact manifold without boundary of dimension greater or equal to 5. Assuming that M has a finite number of tame ends and a neighbourhood U of infinity at each end, let D (M) be the simplicial group of self-diffeomorphisms of M. The results showed the existence of a fibration map from D (M) to the disjoint union of D (U) with homotopy fibre equivalent to the space of diffeomorphisms with compact support D c(M).

  9. Isolated right ventricular takotsubo cardiomyopathy: a case report and literature review.

    PubMed

    Elikowski, Waldemar; Małek-Elikowska, Małgorzata; Różańska, Paulina; Fertała, Natalia; Zawodna, Magdalena

    2016-12-22

    In about one quarter of patients with stress-induced takotsubo cardiomyopathy (TC) concomitant involvement of right ventricle (RV) can be observed. Opposite to this biventricular form of TC, isolated right ventricular takotsubo cardiomyopathy (RVTC) was described only in a few cases and so far has not been listed as a specific type of TC. The authors present a case of a 87-year-old demented female admitted with pneumonia in whom echocardiography revealed RV apical ballooning while the left ventricle function was quite normal. RV apical thrombus was also found. Initial ECG showed QR in V1, discrete ST elevation in V1-2 leads and low voltage of QRS complex in limb leads. There was only a slight increase in troponin I level but a marked BNP elevation. Despite treatment, the course of the disease ended in a fiasco. The authors compare the clinical picture of the patient presented with the data of the 6 remaining cases of isolated RVTC found in the literature. Routine echocardiographic evaluation of RV in different clinical situations which may trigger TC should show actual occurrence of isolated RVTC.

  10. Left ventricular apical diseases.

    PubMed

    Cisneros, Silvia; Duarte, Ricardo; Fernandez-Perez, Gabriel C; Castellon, Daniel; Calatayud, Julia; Lecumberri, Iñigo; Larrazabal, Eneritz; Ruiz, Berta Irene

    2011-08-01

    There are many disorders that may involve the left ventricular (LV) apex; however, they are sometimes difficult to differentiate. In this setting cardiac imaging methods can provide the clue to obtaining the diagnosis. The purpose of this review is to illustrate the spectrum of diseases that most frequently affect the apex of the LV including Tako-Tsubo cardiomyopathy, LV aneurysms and pseudoaneurysms, apical diverticula, apical ventricular remodelling, apical hypertrophic cardiomyopathy, LV non-compaction, arrhythmogenic right ventricular dysplasia with LV involvement and LV false tendons, with an emphasis on the diagnostic criteria and imaging features. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13244-011-0091-6) contains supplementary material, which is available to authorized users.

  11. Perventricular device closure of isolated muscular ventricular septal defect in infants: A single centre experience☆

    PubMed Central

    Thakkar, Bhavesh; Patel, Nehal; Shah, Shaunak; Poptani, Vishal; Madan, Tarun; Shah, Chirag; Shukla, Anand; Prajapati, Vaishali

    2012-01-01

    Objectives To evaluate prospective single centre experience of mid-term safety and efficacy of perventricular device closure of isolated large muscular ventricular septal defect (mVSD) in high-risk infants. Background Surgical closures of large mVSD in infants represent a challenge with significant morbidity. Methods Between August 2008–2010, perventricular closure was attempted in 24 infants of 6.01 ± 2.37 months age and 4.27 ± 0.56 kg weight under TEE guidance. Results The device was successfully deployed in 21/24 infants. Size of mVSD was 8.42 ± 1.46 mm (6.1–12 mm). Mean procedure time was 28.8 ± 11.7 min. The closure rate was 84% immediately and 100% at 6 months. Four patients suffered major complications: 2-died, 1-esophageal perforation, 1-persistent CHB. At 26.23 ± 6.63 months follow-up two patients were symptomatic: 1-required device retrieval, 1-died of severe gastroenteritis. Conclusion Perventricular device closure of isolated mVSD appears feasible option at mid-term follow-up and may either substitute or complement the conventional surgical technique in selected cases depending on institutional paediatric cardiac surgery performance. PMID:23253407

  12. The Impact of Isolated Obesity on Right Ventricular Function in Young Adults

    PubMed Central

    Sokmen, Abdullah; Sokmen, Gulizar; Acar, Gurkan; Akcay, Ahmet; Koroglu, Sedat; Koleoglu, Murat; Yalcintas, Sila; Aydin, M. Naci

    2013-01-01

    Background Obesity is an independent risk factor for cardiovascular diseases. The effects of obesity on left ventricular structure and function have been reported, but relatively little is known regarding right ventricular (RV) function in obesity. Objective To evaluate subclinical RV alterations in obese, but otherwise healthy, young adults by conventional echocardiography and tissue Doppler imaging (TDI). Methods In this study, we included 35 normal weight healthy subjects with a body mass index (BMI) < 25 kg/m2 (group I), 27 subjects with a BMI of 30-34.99 kg/m2 (group II), and 42 subjects with a BMI ≥ 35 kg/m2 (group III). All subjects underwent transthoracic echocardiography. In addition to standard echocardiographic measurements, tricuspid annular peak systolic (Sm), peak early (Em), and late diastolic (Am) velocities, isovolumetric contraction (ICTm), relaxation (IRTm) time, and ejection time (ETm) were obtained by TDI, and RV myocardial performance index (MPIm) was calculated. Results In group II, RV Em/Am was significantly decreased and IRTm and MPIm were significantly increased compared to group I (p < 0.01). RV Sm, Em, and the Em/Am ratio were significantly lower and RV IRTm and MPIm were significantly higher in group III than in group II (p < 0.05 for RV Sm and IRTm and p < 0.01 for others). RV Am differed significantly between groups III and I (p < 0.05). BMI was significantly and negatively correlated with RV Sm, Em, and the Em/Am ratio, but positively correlated with RV MPI (p < 0.01). Conclusion Our study showed that isolated obesity in young normotensive adults was associated with subclinical abnormalities in RV structure and function. PMID:23842799

  13. Non-compact nonlinear sigma models

    NASA Astrophysics Data System (ADS)

    de Rham, Claudia; Tolley, Andrew J.; Zhou, Shuang-Yong

    2016-09-01

    The target space of a nonlinear sigma model is usually required to be positive definite to avoid ghosts. We introduce a unique class of nonlinear sigma models where the target space metric has a Lorentzian signature, thus the associated group being non-compact. We show that the would-be ghost associated with the negative direction is fully projected out by 2 second-class constraints, and there exist stable solutions in this class of models. This result also has important implications for Lorentz-invariant massive gravity: There exist stable nontrivial vacua in massive gravity that are free from any linear vDVZ-discontinuity and a Λ2 decoupling limit can be defined on these vacua.

  14. Dispersion-based reentry: mechanism of initiation of ventricular tachycardia in isolated rabbit hearts.

    PubMed

    Robert, E; Aya, A G; de la Coussaye, J E; Péray, P; Juan, J M; Brugada, J; Davy, J M; Eledjam, J J

    1999-02-01

    The aim of the study was to determine whether facilitation of reentry by potassium-channel openers is related to dispersion of refractoriness and/or modification of anisotropic properties of ventricular myocardium. The dispersion of ventricular effective refractory period (VERP), longitudinal and transverse ventricular conduction velocities (thetaL and thetaT, respectively), and wavelength [lambda = VERP x theta(L or T)] were studied in Langendorff-perfused left ventricular epicardium in 20 rabbits during infusion of incremental doses of levcromakalim or nicorandil. Dispersion of refractoriness was assessed using standard deviation of VERP mean (SD-VERP), dispersion index (DI; SD-VERP/mean VERP), and maximum dispersion (Dmax = VERPmax - VERPmin). Ventricular conduction velocities and anisotropic ratio were not modified, whatever the dose used. VERP and lambda were significantly shortened at high concentrations of levcromakalim and nicorandil. At these doses, SD-VERP, DI, and Dmax were increased significantly. Analysis of ventricular tachycardia induction, performed using a high-resolution ventricular mapping system, confirmed that heterogeneity and shortening of VERP were factors inducing functional conduction block. Our data suggest that, in rabbit left ventricular epicardium, functional conduction block facilitating the occurrence of reentry could be initiated by shortening and, especially, by dispersion of refractoriness during infusion of potassium-channel openers.

  15. Characterization of two distinct depolarization-activated K+ currents in isolated adult rat ventricular myocytes

    PubMed Central

    1991-01-01

    Depolarization-activated outward K+ currents in isolated adult rat ventricular myocytes were characterized using the whole-cell variation of the patch-clamp recording technique. During brief depolarizations to potentials positive to -40 mV, Ca(2+)-independent outward K+ currents in these cells rise to a transient peak, followed by a slower decay to an apparent plateau. The analyses completed here reveal that the observed outward current waveforms result from the activation of two kinetically distinct voltage-dependent K+ currents: one that activates and inactivates rapidly, and one that activates and inactivates slowly, on membrane depolarization. These currents are referred to here as Ito (transient outward) and IK (delayed rectifier), respectively, because their properties are similar (although not identical) to these K+ current types in other cells. Although the voltage dependences of Ito and IK activation are similar, Ito activates approximately 10-fold and inactivates approximately 30-fold more rapidly than IK at all test potentials. In the composite current waveforms measured during brief depolarizations, therefore, the peak current predominantly reflects Ito, whereas IK is the primary determinant of the plateau. There are also marked differences in the voltage dependences of steady-state inactivation of these two K+ currents: IK undergoes steady-state inactivation at all potentials positive to -120 mV, and is 50% inactivated at -69 mV; Ito, in contrast, is insensitive to steady-state inactivation at membrane potentials negative to -50 mV. In addition, Ito recovers from steady-state inactivation faster than IK: at -90 mV, for example, approximately 70% recovery from the inactivation produced at -20 mV is observed within 20 ms for Ito; IK recovers approximately 25-fold more slowly. The pharmacological properties of Ito and IK are also distinct: 4-aminopyridine preferentially attenuates Ito, and tetraethylammonium suppresses predominantly IK. The voltage- and

  16. Isolation of the Left Subclavian Artery with Right Aortic Arch in Association with Bilateral Ductus Arteriosus and Ventricular Septal Defect

    PubMed Central

    Lee, Ji Seong; Park, Ji Young; Ko, Seong Min; Seo, Dong-Man

    2015-01-01

    Right aortic arch with isolation of the left subclavian artery is a rare anomaly. The incidence of bilateral ductus arteriosus is sporadic, and a right aortic arch with isolation of the left subclavian artery in association with bilateral ductus arteriosus is therefore extremely rare. Since the symptoms and signs of isolation of the left subclavian artery can include the absence or underdevelopment of the left arm, subclavian steal syndrome, or pulmonary artery steal syndrome, the proper therapeutic approach is controversial. We report a case in which surgical reconstruction was used to treat isolation of the left subclavian artery with right aortic arch in association with bilateral ductus arteriosus and a ventricular septal defect. PMID:26665110

  17. Itraconazole decreases left ventricular contractility in isolated rabbit heart: Mechanism of action

    SciTech Connect

    Qu, Yusheng; Fang, Mei; Gao, BaoXi; Amouzadeh, Hamid R.; Li, Nianyu; Narayanan, Padma; Acton, Paul; Lawrence, Jeff; Vargas, Hugo M.

    2013-04-15

    Itraconazole (ITZ) is an approved antifungal agent that carries a “black box warning” in its label regarding a risk of negative cardiac inotropy based on clinical findings. Since the mechanism of the negative inotropic effect is unknown, we performed a variety of preclinical and mechanistic studies to explore the pharmacological profile of ITZ and understand the negative inotropic mechanism. ITZ was evaluated in: (1) an isolated rabbit heart (IRH) preparation using Langendorff retrograde perfusion; (2) ion channel studies; (3) a rat heart mitochondrial function profiling screen; (4) a mitochondrial membrane potential (MMP) assay; (5) in vitro pharmacology profiling assays (148 receptors, ion channels, transporters, and enzymes); and (6) a kinase selectivity panel (451 kinases). In the IRH, ITZ decreased cardiac contractility (> 30%) at 0.3 μM, with increasing effect at higher concentrations, which indicated a direct negative inotropic effect upon the heart. It also decreased heart rate and coronary flow (≥ 1 μM) and prolonged PR/QRS intervals (3 μM). In mechanistic studies, ITZ inhibited the cardiac NaV channel (IC{sub 50}: 4.2 μM) and was devoid of any functional inhibitory effect at the remaining pharmacological targets. Lastly, ITZ did not affect MMP, nor interfere with mitochondrial enzymes or processes involved with fuel substrate utilization or energy formation. Overall, the cardiovascular and mechanistic data suggest that ITZ-induced negative inotropy is a direct effect on the heart, in addition, the potential involvement of mitochondria function and L-type Ca{sup 2+} channels are eliminated. The exact mechanism underlying the negative inotropy is uncertain, and requires further study. - Highlights: ► Effect of itraconazole (ITZ) was assessed in the isolated rabbit heart (IRH) assay. ► ITZ decreased ventricular contractility in IRH, indicating a direct effect. ► IC{sub 50} of ITZ on L-type I{sub Ca} was greater than 30 μM, on I{sub Na} was 4

  18. Ventricular filling slows epicardial conduction and increases action potential duration in an optical mapping study of the isolated rabbit heart

    NASA Technical Reports Server (NTRS)

    Sung, Derrick; Mills, Robert W.; Schettler, Jan; Narayan, Sanjiv M.; Omens, Jeffrey H.; McCulloch, Andrew D.; McCullough, A. D. (Principal Investigator)

    2003-01-01

    INTRODUCTION: Mechanical stimulation can induce electrophysiologic changes in cardiac myocytes, but how mechanoelectric feedback in the intact heart affects action potential propagation remains unclear. METHODS AND RESULTS: Changes in action potential propagation and repolarization with increased left ventricular end-diastolic pressure from 0 to 30 mmHg were investigated using optical mapping in isolated perfused rabbit hearts. With respect to 0 mmHg, epicardial strain at 30 mmHg in the anterior left ventricle averaged 0.040 +/- 0.004 in the muscle fiber direction and 0.032 +/- 0.006 in the cross-fiber direction. An increase in ventricular loading increased average epicardial activation time by 25%+/- 3% (P < 0.0001) and correspondingly decreased average apparent surface conduction velocity by 16%+/- 7% (P = 0.007). Ventricular loading did not significantly alter action potential duration at 20% repolarization (APD20) but did at 80% repolarization (APD80), from 179 +/- 7 msec to 207 +/- 5 msec (P < 0.0001). The dispersion of APD20 was decreased with loading from 19 +/- 2 msec to 13 +/- 2 msec (P = 0.024), whereas the dispersion of APD80 was not significantly changed. These electrophysiologic changes with ventricular loading were not affected by the nonspecific stretch-activated channel blocker streptomycin (200 microM) and were not attributable to changes in myocardial perfusion or the presence of an electromechanical decoupling agent (butanedione monoxime) during optical mapping. CONCLUSION: Acute loading of the left ventricle of the isolated rabbit heart decreased apparent epicardial conduction velocity and increased action potential duration by a load-dependent mechanism that may not involve stretch-activated channels.

  19. Ventricular filling slows epicardial conduction and increases action potential duration in an optical mapping study of the isolated rabbit heart

    NASA Technical Reports Server (NTRS)

    Sung, Derrick; Mills, Robert W.; Schettler, Jan; Narayan, Sanjiv M.; Omens, Jeffrey H.; McCulloch, Andrew D.; McCullough, A. D. (Principal Investigator)

    2003-01-01

    INTRODUCTION: Mechanical stimulation can induce electrophysiologic changes in cardiac myocytes, but how mechanoelectric feedback in the intact heart affects action potential propagation remains unclear. METHODS AND RESULTS: Changes in action potential propagation and repolarization with increased left ventricular end-diastolic pressure from 0 to 30 mmHg were investigated using optical mapping in isolated perfused rabbit hearts. With respect to 0 mmHg, epicardial strain at 30 mmHg in the anterior left ventricle averaged 0.040 +/- 0.004 in the muscle fiber direction and 0.032 +/- 0.006 in the cross-fiber direction. An increase in ventricular loading increased average epicardial activation time by 25%+/- 3% (P < 0.0001) and correspondingly decreased average apparent surface conduction velocity by 16%+/- 7% (P = 0.007). Ventricular loading did not significantly alter action potential duration at 20% repolarization (APD20) but did at 80% repolarization (APD80), from 179 +/- 7 msec to 207 +/- 5 msec (P < 0.0001). The dispersion of APD20 was decreased with loading from 19 +/- 2 msec to 13 +/- 2 msec (P = 0.024), whereas the dispersion of APD80 was not significantly changed. These electrophysiologic changes with ventricular loading were not affected by the nonspecific stretch-activated channel blocker streptomycin (200 microM) and were not attributable to changes in myocardial perfusion or the presence of an electromechanical decoupling agent (butanedione monoxime) during optical mapping. CONCLUSION: Acute loading of the left ventricle of the isolated rabbit heart decreased apparent epicardial conduction velocity and increased action potential duration by a load-dependent mechanism that may not involve stretch-activated channels.

  20. Posterior left atrial isolation for atrial fibrillation in left ventricular diastolic impairment is associated with better arrhythmia free survival.

    PubMed

    Nalliah, Chrishan; Lim, Toon Wei; Bhaskaran, Abhishek; Kizana, Eddy; Kovoor, Pramesh; Thomas, Liza; Ross, David L; Thomas, Stuart P

    2015-04-01

    Patients with left ventricular diastolic impairment (LVDI) have higher rates of arrhythmia recurrence following atrial fibrillation (AF) ablation. Past studies have implicated the posterior left atrium (LA) in atrial arrhythmia maintenance in conditions that cause LVDI. We prospectively compared posterior LA isolation (PLAI) with wide antral isolation (WAI) in patients with LVDI having AF ablation. We conducted a sub-study of a previously published large randomized control study that compared PLAI with WAI. Two hundred and twenty consecutive consenting patients referred for catheter ablation of AF (paroxysmal 135, persistent 48, long standing persistent 37) were recruited (female 43, mean age 59 ± 10 years). Transthoracic echocardiography identified 50 (23%) patients with LVDI and preserved left ventricular systolic function (ejection fraction ≥ 50%). Cox regression analysis was utilized to identify independent predictors of atrial arrhythmia after ablation. Patients were followed for median 4.6 (inter quartile range 4.0-5.5) years. Patients with LVDI having PLAI had better arrhythmia free survival than patients randomized to conventional ablation (Log rank P=0.028). The only independent predictor of recurrence utilizing Cox regression analysis was ablation strategy (2.3 [1.15-4.74], P=0.026). Posterior isolation of the LA results in superior atrial arrhythmia free survival in patients with LVDI. Further investigation is required to determine potential mechanisms. http://www.anzctr.org.au;ACTRN12606000467538. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

  1. Comparative effects of clarithromycin on action potential and ionic currents from rabbit isolated atrial and ventricular myocytes.

    PubMed

    Gluais, Pascale; Bastide, Michìle; Caron, Jacques; Adamantidis, Monique

    2003-04-01

    Prolongation of QT interval by several antibacterial drugs is an unwanted side effect that may be associated with development of ventricular arrhythmias. The macrolide antibacterial agent clarithromycin has been shown to cause QT prolongation. To determine the electrophysiologic basis for this arrhythmogenic potential, we investigated clarithromycin effects on (i). action potentials recorded from rabbit Purkinje fibers and atrial and ventricular myocardium using conventional microelectrodes and (ii). potassium and calcium currents recorded from rabbit atrial and ventricular isolated myocytes using whole-cell patch clamp recordings. We found that (i). clarithromycin (3-100 microM) exerted concentration-dependent lengthening effects on action potential duration in all tissues, with higher efficacy and reverse frequency-dependence in Purkinje fibers. However, clarithromycin did not cause development of early afterdepolarizations, and the parameters other than action potential duration were almost unaffected; (ii). clarithromycin (10-100 microM) reduced the delayed rectifier current. Significant blockade (approximately 30%) was found at the concentration of 30 microM. At 100 microM, it decreased significantly the maximum peak of the calcium current amplitude but failed to alter the transient outward and inwardly rectifier currents. It was concluded that these effects might be an explanation for the QT prolongation observed in some patients treated with clarithromycin.

  2. Electrical properties of individual cells isolated from adult rat ventricular myocardium.

    PubMed

    Powell, T; Terrar, D A; Twist, V W

    1980-05-01

    1. Individual cells were isolated from adult rats ventricular myocardium by a collagenase digestion procedure. 2. Steady membrane potentials recorded with conventional intracellular glass micro-electrodes from cells in a modified Krebs solution containing 3 . 8 mM-KCl and 0 . 5 mM-CaCl2 were less negative than -40 mV in most cells (-25 . 3 +/- 10 . 9 mV, mean +/- S.D., 211 cells). 3. After addition of the potassium selective ionophore valinomycin (60 nM) to the bathing solution all recorded membrane potentials were more negative than -60 mV (-74 . 8 +/- 7 . 0 mV, sixty-three cells). 4. The internal concentration of potassium in the cells was determined as 120 . 8 +/- 1 . 7 mM (+/- S.E., n = 24) by flame emission spectrometry after centrifugation through silicone oil, using tritiated water and D-[1-14C] mannitol to estimate total and extracellular water in the pellet. 5. In the majority of cells in the standard solution the membrane potential recorded within a few msec of penetration was more negative than -70 mV (-78 . 4 +/- 9 . 7 mV, seventy-three cells). In sixty-six cells penetration initiated an action potential which overshot zero by 31 . 3 +/- 7 . 1 mV. This overshoot was abolished by reducing the external sodium to 0 . 1 of the normal value, and reduced or abolished by addition of tetrodotoxin (30 microM). 6. Modifications of the standard bathing solution which increased the number of cells with steady recorded membrane potentials more negative than -60 mV were: isosmotic substitution of sucrose for NaCl; replacement of NaCl and KCl by sodium isethionate and potassium methyl sulphate; addition of 5 or 10 mM-CaCl2; addition of 10 mM-MnCl2. 7. For cells in solution containing 2 . 5 or 5 . 5 mM-CaCl2, input resistances estimated from the amplitude of hyperpolarizations evoked by 200 msec current pulses were approximately 40 M omega at a resting potential close to -80 mV and became much greater as cells were depolarized. Time constants measured at the resting

  3. Left ventricular mechanics in isolated mild mitral stenosis: a three dimensional speckle tracking study.

    PubMed

    Poyraz, Esra; Öz, Tuğba Kemaloğlu; Zeren, Gönül; Güvenç, Tolga Sinan; Dönmez, Cevdet; Can, Fatma; Güvenç, Rengin Çetin; Dayı, Şennur Ünal

    2017-03-11

    In a fraction of patients with mild mitral stenosis, left ventricular systolic function deteriorates despite the lack of hemodynamic load imposed by the dysfunctioning valve. Neither the predisposing factors nor the earlier changes in left ventricular contractility were understood adequately. In the present study we aimed to evaluate left ventricular mechanics using three-dimensional (3D) speckle tracking echocardiography. A total of 31 patients with mild rheumatic mitral stenosis and 27 healthy controls were enrolled to the study. All subjects included to the study underwent echocardiographic examination to collect data for two- and three-dimensional speckle-tracking based stain, twist angle and torsion measurements. Data was analyzed offline with a echocardiographic data analysis software. Patients with rheumatic mild MS had lower global longitudinal (p < 0.001) circumferential (p = 0.02) and radial (p < 0.01) strain compared to controls, despite ejection fraction was similar for both groups [(p = 0.45) for three dimensional and (p = 0.37) for two dimensional measurement]. While the twist angle was not significantly different between groups (p = 0.11), left ventricular torsion was significantly higher in mitral stenosis group (p = 0.03). All strain values had a weak but significant positive correlation with mitral valve area measured with planimetry. Subclinical left ventricular systolic dysfunction develops at an early stage in rheumatic mitral stenosis. Further work is needed to elucidate patients at risk for developing overt systolic dysfunction.

  4. A high-resolution thermoelectric module-based calorimeter for measuring the energetics of isolated ventricular trabeculae at body temperature.

    PubMed

    Johnston, Callum M; Han, June-Chiew; Ruddy, Bryan P; Nielsen, Poul M F; Taberner, Andrew J

    2015-07-15

    Isolated ventricular trabeculae are the most common experimental preparations used in the study of cardiac energetics. However, the experiments have been conducted at subphysiological temperatures. We have overcome this limitation by designing and constructing a novel calorimeter with sufficiently high thermal resolution for simultaneously measuring the heat output and force production of isolated, contracting, ventricular trabeculae at body temperature. This development was largely motivated by the need to better understand cardiac energetics by performing such measurements at body temperature to relate tissue performance to whole heart behavior in vivo. Our approach uses solid-state thermoelectric modules, tailored for both temperature sensing and temperature control. The thermoelectric modules have high sensitivity and low noise, which, when coupled with a multilevel temperature control system, enable an exceptionally high temperature resolution with a noise-equivalent power an order of magnitude greater than those of other existing muscle calorimeters. Our system allows us to rapidly and easily change the experimental temperature without disturbing the state of the muscle. Our calorimeter is useful in many experiments that explore the energetics of normal physiology as well as pathophysiology of cardiac muscle. Copyright © 2015 the American Physiological Society.

  5. Hemodynamic instability after pulmonary veins isolation in a patient with dual chamber pacemaker: The phantom injury of the ventricular lead.

    PubMed

    Kiuchi, Márcio Galindo; Lobato, Guilherme Miglioli; Chen, Shaojie

    2017-06-01

    The standard treatment of sinus node dysfunction (SND) is the pacemaker implantation, and the ideal methodology for the management of atrial fibrillation (AF) is rhythm control, but this is sometimes very hard to accomplish. For such actions, complete isolation of all pulmonary veins (PVI) is currently widely accepted as the best endpoint. In this case, we report a female patient, 81 years old, with controlled hypertension, without coronary artery disease, bearer of bilateral knee replacement, and dual chamber pacemaker implanted 1.5 years ago owing to sinus node disease, presenting the following symptoms: presyncope episodes associated with sustained irregular palpitation tachycardia. The evaluation of the pacemaker-recorded episodes of atrial fibrillation, the echocardiogram-presented normal systolic function and measurements, as well as the resting myocardial scintigraphy and with drug use did not demonstrate ischemia and/or fibrosis. The patient was in use of valsartan 320 mg daily, amlodipine 10 mg daily, sotalol hydrochloride 120 mg 2 times daily, and dabigatran 110 mg 2 times daily. At the end of the PVI, the patient presented hemodynamic instability, with a decrease in heart rate to 30 bpm and invasive arterial blood pressure to 60/30 mmHg. The pericardial puncture was quickly carried out with the possibility of cardiac tamponade as the first hypothesis, but no pericardial effusion was found. Next, we detected acute capture loss from the ventricular pacemaker lead, unvarying with high voltage and pulse width, even with stable impedance, sense and keeping the same position visualized by fluoroscopy. And there was soon afterwards induction of sustained ventricular tachycardia degenerating to spontaneous ventricular fibrillation. Electrical cardioversion-defibrillation was performed with 200J, and the sinus rhythm was reestablished, but there was a dead short, and the pacemaker generator was burned and disabled. So, we can speculate that

  6. Arterial-ventricular and interventricular interaction in isolated post-capillary and combined pulmonary hypertension in severe mitral stenosis.

    PubMed

    Venkateshvaran, Ashwin; Sola, Srikanth; Govind, Satish Chandra; Dash, Pravat Kumar; Vyavahare, Sagar; Lund, Lars H; la Merkely, Bé; Nagy, Anikó Ilona; Manouras, Aristomenis

    2016-08-01

    Isolated post-capillary pulmonary hypertension (Ipc-PH) is characterized by elevated left atrial pressures that are passively transmitted upstream, whereas combined pre- and post-capillary PH (Cpc-PH) demonstrates additional reactive changes in pulmonary vasculature. The increased load imposed on the right ventricle (RV) influences left ventricular (LV) mechanics by means of interventricular interaction. However, there is lack of evidence to substantiate the effect of possible additional alterations in the arterio-ventricular (AV) coupling and their effect on LV function. Considering the discrepant RV load in Cpc-PH and Ipc-PH, we sought to investigate whether these two conditions are also characterized by differential alterations in AV coupling. Invasive hemodynamic and echocardiographic data of 120 patients with PH due to severe rheumatic mitral stenosis before and immediately after percutaneous valvulotomy, along with 40 age-matched healthy controls, were analyzed. Effective arterial (E a) and ventricular elastance (E es) were measured. PH patients demonstrated elevated LV afterload (E a) along with AV uncoupling, and these derangements were more evident in the Cpc-PH group [E a: 3.3 (2.3-5.4) vs 2.6 (2.1-3.5) mmHg/mL, E a/E es: 0.73 (0.6-0.9) vs 0.88 (0.7-1.2), p < 0.05]. In addition, PH was associated with reduced LV deformation, which was mainly determined by elevated E a, while the effect of interventricular interaction was limited to the septal wall. Our results suggest that in addition to the interventricular interaction, an abnormal AV coupling contributes to the altered LV mechanics that has been associated with adverse prognosis in Cpc-PH.

  7. Exercise capacity and ventricular function in patients treated for isolated pulmonary valve stenosis or tetralogy of Fallot.

    PubMed

    Luijnenburg, Saskia E; de Koning, Wilfred B; Romeih, Soha; van den Berg, Jochem; Vliegen, Hubert W; Mulder, Barbara J M; Helbing, Willem A

    2012-07-26

    We hypothesized 1) that long-term ventricular outcome and exercise capacity would be better in patients with isolated pulmonary valve stenosis (PS) treated with balloon pulmonary valvuloplasty (BPV) than in patients operated for tetralogy of Fallot (TOF), and 2) that ventricular outcome and exercise capacity would not be different in PS patients and healthy controls. We included 21 PS patients after BPV (16.2 ± 5.2 years) and 21 patients operated for TOF (16.6 ± 5.6 years), matching them for gender, age at treatment, and age at study. Patients underwent cardiovascular magnetic resonance (CMR) imaging, exercise testing, 12-lead ECG and 24-hour Holter monitoring for assessment of right ventricular (RV) size and function, pulmonary regurgitation (PR), exercise capacity and electrocardiographic status. Healthy controls for CMR imaging and exercise testing were matched for gender and age at study. RV volumes and PR percentage were significantly larger in TOF patients than in PS patients; biventricular ejection fraction (EF) was not different. PR was mild in most PS patients. RV end-systolic volume was significantly larger in PS patients than in healthy controls; RVEF was significantly lower. Both patient groups had similar exercise test results. Peak workload and VO(2) max. were significantly lower in PS patients than in healthy controls. Longstanding mild PR in PS patients can lead to an enlarged RV, reduced RV function and reduced exercise capacity. Despite more PR and larger RV volumes in TOF patients, exercise capacity and biventricular function are similar in both patient groups. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  8. Effects of L-propionylcarnitine on electrical and mechanical alterations induced by amphiphilic lipids in isolated guinea pig ventricular muscle.

    PubMed

    Aomine, M; Arita, M; Shimada, T

    1988-01-01

    We examined the effects of L-propionylcarnitine (Prop. C), a short-chain acylcarnitine, on amphiphile (L-lysophosphatidylcholine or L-palmitoylcarnitine)-induced electrophysiological and ultrastructural changes in isolated guinea pig ventricular papillary muscles, under acidic conditions (pH 6.9). Conventional microelectrode, tension-recording, and electron microscope techniques were used. Both amphiphiles, at a concentration of 10(-4) M, significantly decreased the resting membrane potential, action potential amplitude, and action potential duration, but increased the developed and resting tension. Such amphiphile-induced electrical changes were not observed in muscles pretreated with the beta-blocker, atenolol, although the mechanical changes remained unaffected. The application of Prop. C (10(-2) M), in the continued presence of the amphiphiles caused a return of the action potential duration and the developed tension to the control level. However, the resting potential and action potential amplitude remained unaffected; in fact, the maximum upstroke velocity (Vmax) of the action potential tended to decrease further. Pretreatment with Prop. C prevented all the amphiphile-induced electrophysiological and mechanical changes, except for Vmax. Electron microscopic studies revealed that amphiphile-induced ultrastructural changes were prevented, at least in part, in the presence of Prop. C. Thus, Prop. C antagonizes some of deleterious effects of amphiphiles, such as lysophosphatidylcholine and palmitoylcarnitine, upon the electrical and mechanical activities of the ventricular muscle, under acidic conditions.

  9. Spatiotemporal complexity of ventricular fibrillation revealed by tissue mass reduction in isolated swine right ventricle. Further evidence for the quasiperiodic route to chaos hypothesis.

    PubMed Central

    Kim, Y H; Garfinkel, A; Ikeda, T; Wu, T J; Athill, C A; Weiss, J N; Karagueuzian, H S; Chen, P S

    1997-01-01

    We have presented evidence that ventricular fibrillation is deterministic chaos arising from quasiperiodicity. The purpose of this study was to determine whether the transition from chaos (ventricular fibrillation, VF) to periodicity (ventricular tachycardia) through quasiperiodicity could be produced by the progressive reduction of tissue mass. In isolated and perfused swine right ventricular free wall, recording of single cell transmembrane potentials and simultaneous mapping (477 bipolar electrodes, 1.6 mm resolution) were performed. The tissue mass was then progressively reduced by sequential cutting. All isolated tissues fibrillated spontaneously. The critical mass to sustain VF was 19.9 +/- 4.2 g. As tissue mass was decreased, the number of wave fronts decreased, the life-span of reentrant wave fronts increased, and the cycle length, the diastolic interval, and the duration of action potential lengthened. There was a parallel decrease in the dynamical complexity of VF as measured by Kolmogorov entropy and Poincaré plots. A period of quasiperiodicity became more evident before the conversion from VF (chaos) to a more regular arrhythmia (periodicity). In conclusion, a decrease in the number of wave fronts in ventricular fibrillation by tissue mass reduction causes a transition from chaotic to periodic dynamics via the quasiperiodic route. PMID:9366563

  10. Left ventricular aneurysm and prognosis in patients with first acute transmural anterior myocardial infarction and isolated left anterior descending artery disease.

    PubMed

    Shen, W F; Tribouilloy, C; Mirode, A; Dufossé, H; Lesbre, J P

    1992-01-01

    To determine the clinical and angiographic factors responsible for left ventricular aneurysm formation and the prognosis of patients with aneurysm, 79 patients with a first acute transmural anterior myocardial infarction and angiographically documented isolated left anterior descending artery disease were retrospectively evaluated. Presence of large infarct size and left ventricular volumes, reduced left ventricular function, and evidence of clinical functional impairment were more common in patients with aneurysm (n = 31) than in those without (n = 48). Patients with aneurysm often had total occlusion of the proximal left anterior descending artery without collateral vessels on angiography. During a mean follow-up of 53 months, 10 patients with and three without aneurysm died (P less than 0.01). Compared to survivors with or without aneurysm, the nonsurvivors were older, had significantly larger infarct size and left ventricular volumes and poor systolic function. The incidence of total occlusion of the left anterior descending artery without collaterals was higher in nonsurvivors. In patients with aneurysm, stepwise multivariate analysis revealed that left ventricular ejection fraction and the status of left anterior descending artery obstruction and collaterals were independent predictors of mortality. The study indicates that in patients with a first acute transmural anterior myocardial infarction and isolated anterior descending artery disease, left ventricular aneurysm often results from a large infarct caused by total occlusion of the proximal left anterior descending artery without collateral supply to the infarct region. The reduced survival rate for patients with aneurysm is primarily related to severe global left ventricular dysfunction which may be determined by assessing the residual flow to the infarct region.

  11. Rigidity of complete noncompact bach-flat n-manifolds

    NASA Astrophysics Data System (ADS)

    Chu, Yawei; Feng, Pinghua

    2012-11-01

    Let (Mn,g) be a complete noncompact Bach-flat n-manifold with the positive Yamabe constant and constant scalar curvature. Assume that the L2-norm of the trace-free Riemannian curvature tensor R∘m is finite. In this paper, we prove that (Mn,g) is a constant curvature space if the L-norm of R∘m is sufficiently small. Moreover, we get a gap theorem for (Mn,g) with positive scalar curvature. This can be viewed as a generalization of our earlier results of 4-dimensional Bach-flat manifolds with constant scalar curvature R≥0 [Y.W. Chu, A rigidity theorem for complete noncompact Bach-flat manifolds, J. Geom. Phys. 61 (2011) 516-521]. Furthermore, when n>9, we derive a rigidity result for R<0.

  12. Mechanisms of action of diltiazem in isolated human atrial and ventricular myocardium.

    PubMed

    Sutton, M S; Morad, M

    1987-05-01

    A comparative study of human atrial fibers (HAF), human ventricular fibers (HVF), frog ventricle, and frog skeletal muscle demonstrated marked differences in tension development in the presence of diltiazem. There was no significant difference between the tension developed by HAF and by HVF over a range of diltiazem concentrations when the differences in resting membrane potential were corrected by increasing external K+ concentration. In human myocardium, diltiazem resulted in both a voltage and use-dependent blockade of the calcium channel. Comparison of the tension-dose response curves in human myocardium, frog ventricle and skeletal muscle showed that diltiazem was most effective at decreasing tension in frog heart, and least effective in skeletal muscle with human myocardium being intermediate. In skeletal muscle, neither tension development nor the birefringence signal related to the Ca2+ release from the sarcoplasmic reticulum was significantly altered by Diltiazem in concentrations less than 10(-6) M, but in concentrations greater than 10(-5) M both were suppressed. Diltiazem suppressed tension in human myocardium over the range of membrane potentials associated with Ca2+ channel activity, while at more positive potentials, diltiazem appeared to have little effect on the tension-voltage relations. Diltiazem had no effect upon tension development induced by acetyl strophanthidin in human myocardium or upon the Ca2+ sensitivity of chemically skinned atrial or ventricular fibers. Thus the tension-suppressant effect of diltiazem in human myocardium appears to be mediated by a combination of voltage-dependent block of the Ca2+ channel and inhibition of Ca2+ release from internal stores, and not from alterations in either Na+-Ca2+ coupled transport or Ca2+ sensitivity of the myofilaments.

  13. A rigidity theorem for complete noncompact Bach-flat manifolds

    NASA Astrophysics Data System (ADS)

    Chu, Yawei

    2011-02-01

    Let (M4,g) be a four-dimensional complete noncompact Bach-flat Riemannian manifold with positive Yamabe constant. In this paper, we show that (M4,g) has a constant curvature if it has a nonnegative constant scalar curvature and sufficiently small L2-norm of trace-free Riemannian curvature tensor. Moreover, we get a gap theorem for (M4,g) with positive scalar curvature.

  14. Topological and affine classification of complete noncompact flat 4-manifolds

    NASA Astrophysics Data System (ADS)

    Sadowski, Michał

    2008-11-01

    In this paper we give topological and affine classification of complete noncompact flat 4-manifolds. In particular, we show that the number of diffeomorphism classes of them is equal to 44. The affine classification uses the results of [M. Sadowski, Affinely equivalent complete flat manifolds, Cent. Eur. J. Math. 2 (2) (2004) 332-338]. The affine and the topological equivalence classes are the same for flat manifolds not homotopy equivalent to S1,T2 or the Klein bottle.

  15. [A full-term pregnant woman with non-compaction cardiomyopathy].

    PubMed

    Bañuls Pellicer, G; Domingo-Triadó, V

    2014-01-01

    Non-compaction cardiomyopathy, a genetic primary cardiomyopathy, is being increasingly diagnosed. Pregnant women with non-compaction cardiomyopathy are more susceptible to complications, such as heart failure, arrhythmias and embolic events. This paper reports the case of a pregnant woman with non-compaction cardiomyopathy under treatment and asymptomatic, who received epidural analgesia during labor and delivery. The clinical course is described and a brief review is presented.

  16. Isolated permanent right ventricular assist device implantation with the HeartWare continuous-flow ventricular assist device: first results from the European Registry for Patients with Mechanical Circulatory Support.

    PubMed

    Bernhardt, Alexander M; De By, Theo M M H; Reichenspurner, Hermann; Deuse, Tobias

    2015-07-01

    Isolated right ventricular (RV) dysfunction with preserved left ventricular function is difficult to treat and associated with high mortality. Temporary devices for right ventricular support [right ventricular assist device (RVAD)] are available and have been used for short-term right heart assistance. In some patients, RV function does not recover and long-term devices are needed. Recently, isolated RVAD implantation with a permanent HeartWare HeartWare ventricular assist device (HVAD) device has been reported in patients with acute RV infarction and chronic graft failure. However, isolated implantation on the right side remains rare and is still an off-label use for this pump. To gather European data, we queried the European Registry for Patients with Mechanical Circulatory Support (EUROMACS) database, in which procedures and outcome data for patients receiving mechanical circulatory support are registered. Until May 2014, data of 8 patients (mean age 55.0 ± 17.3 years, 100% males) with an isolated HVAD for RV support were submitted to the EUROMACS registry. All patients were in INTERMACS classes 1-3. Device strategy was rescue therapy in 6 patients (75.0%) and destination therapy in 2 patients (25.0%). Indications for RVAD placement were acute myocardial infarction in 4 (50.0%), failure to wean from cardiopulmonary bypass in 2 (25.0%) and post-cardiotomy RV failure in another 2 patients (25.0%). Intra- and postoperative results of the EUROMACS registry were analysed. Inflow cannulas were implanted into the right atrium (RA) in 6 patients (75.0%) and into the RV in 2 patients (25.0%). CPB was used in 6 patients (75.0%). Four patients (50.0%) survived the first 30 days. During follow-up, 1 patient died after 44 days due to multiorgan failure. In the surviving three patients, 2 patients were transplanted after 29 and 419 days, respectively, and, in 1 patient, the device was explanted for pump thrombosis and recovered RV function. In this very specific and sick

  17. Gap junction modifier rotigaptide decreases the susceptibility to ventricular arrhythmia by enhancing conduction velocity and suppressing discordant alternans during therapeutic hypothermia in isolated rabbit hearts.

    PubMed

    Hsieh, Yu-Cheng; Lin, Jiunn-Cherng; Hung, Chen-Ying; Li, Cheng-Hung; Lin, Shien-Fong; Yeh, Hung-I; Huang, Jin-Long; Lo, Chu-Pin; Haugan, Ketil; Larsen, Bjarne D; Wu, Tsu-Juey

    2016-01-01

    Therapeutic hypothermia (TH) may increase the susceptibility to ventricular arrhythmias by decreasing ventricular conduction velocity (CV) and facilitating arrhythmogenic spatially discordant alternans (SDA). The purpose of this study was to test the hypothesis that rotigaptide, a gap junction enhancer, can increase ventricular CV, delay the onset of SDA, and decrease the susceptibility to pacing-induced ventricular fibrillation (PIVF) during TH. Langendorff-perfused isolated rabbit hearts were subjected to 30-minute moderate hypothermia (33°C) followed by 20-minute treatment with rotigaptide (300 nM, n = 8) or vehicle (n = 5). The same protocol was also performed at severe hypothermia (30°C; n = 8 for rotigaptide, n = 5 for vehicle). Using an optical mapping system, epicardial CV and SDA threshold were evaluated by S1 pacing. Ventricular fibrillation inducibility was evaluated by burst pacing for 30 seconds at the shortest pacing cycle length (PCL) that achieved 1:1 ventricular capture. Rotigaptide increased ventricular CV during 33°C (PCL 300 ms, from 76 ± 6 cm/s to 84 ± 7 cm/s, P = .039) and 30°C (PCL 300 ms, from 62 ± 6 cm/s to 68 ± 4 cm/s, P = .008). Rotigaptide decreased action potential duration dispersion at 33°C (P = .01) and 30°C (P = .035). During 30°C, SDA thresholds (P = .042) and incidence of premature ventricular complexes (P = .025) were decreased by rotigaptide. PIVF inducibility was decreased by rotigaptide at 33°C (P = .039) and 30°C (P = .042). Rotigaptide did not change connexin43 expressions and distributions during hypothermia. Rotigaptide protects the hearts against ventricular arrhythmias by increasing ventricular CV, delaying the onset of SDA, and reducing repolarization heterogeneity during TH. Enhancing cell-to-cell coupling by rotigaptide might be a novel approach to prevent ventricular arrhythmias during TH. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  18. Characterization of the hyperpolarization-activated current, I(f), in ventricular myocytes isolated from hypertensive rats.

    PubMed Central

    Cerbai, E; Barbieri, M; Mugelli, A

    1994-01-01

    1. Left ventricular myocytes isolated from the heart of young (2-month-old) and old (18- to 20-month-old) spontaneously hypertensive rats (SHRs) were studied in the whole-cell configuration. Since multicellular preparations from old SHRs show a diastolic depolarization phase, we performed experiments to test whether it was associated with the presence of a hyperpolarization-activated If-like current. 2. In control Tyrode solution, a time-dependent increasing inward current activated by hyperpolarization was recorded in myocytes from old SHRs showing a diastolic depolarization phase. A barium-insensitive, caesium-sensitive, time-dependent inward current was recorded in a minority (4 of 33) of cells from young SHRs (membrane capacitance, 160 +/- 7 pF) but in 93% (25 of 27, P < 0.01) of myocytes from old SHRs (membrane capacitance, 355 +/- 19 pF, P < 0.01). 3. The current was fully activated at -120 mV and voltage of half-maximal activation was -88.1 +/- 1.5 mV; it was blocked by extracellular CsCl (4 mM) in a voltage-dependent manner. Reducing [K+]o from 25 to 5.4 mM caused a shift of the reversal potential from -17.3 +/- 3.8 to -25.7 +/- 2.7 mV and a 60% decrease of current conductance. 4. These findings suggest that an If-like current is present in rat ventricular myocytes from old SHRs, where it might favour the occurrence of spontaneous action potentials. PMID:7707227

  19. Isolated pulmonary regurgitation causes decreased right ventricular longitudinal function and compensatory increased septal pumping in a porcine model.

    PubMed

    Kopic, S; Stephensen, S S; Heiberg, E; Arheden, H; Bonhoeffer, P; Ersbøll, M; Vejlstrup, N; Søndergaard, L; Carlsson, M

    2017-06-05

    Longitudinal ventricular contraction is a parameter of cardiac performance with predictive power. Right ventricular (RV) longitudinal function is impaired in patients with free pulmonary regurgitation (PR) following corrective surgery for Tetralogy of Fallot (TOF). It remains unclear whether this is a consequence of the surgical repair, or whether it is inherent to PR. The aim of this study was to assess the relationship between longitudinal, lateral and septal pumping in a porcine model of isolated PR. Piglets were divided into a control (n = 8) group and a treatment (n = 12) group, which received a stent in the pulmonary valve orifice, inducing PR. After 2-3 months, animals were subjected to cardiac magnetic resonance imaging. A subset of animals (n = 6) then underwent percutaneous pulmonary valve replacement (PPVR) with follow-up 1 month later. Longitudinal, lateral and septal contributions to stroke volume (SV) were quantified by measuring volumetric displacements from end-diastole to end-systole in the cardiac short axis and long axis. PR resulted in a lower longitudinal contribution to RV stroke volume, compared to controls (60.0 ± 2.6% vs. 73.6 ± 3.8%; P = 0.012). Furthermore, a compensatory increase in septal contribution to RVSV was observed (11.0 ± 1.6% vs. -3.1 ± 1.5%; P < 0.0001). The left ventricle (LV) showed counter-regulation with an increased longitudinal LVSV. Changes in RV longitudinal function were reversed by PPVR. These findings suggest that PR contributes to decreased RV longitudinal function in the absence of scarring from cardiac surgery. Measurement of longitudinal RVSV may aid risk stratification and timing for interventional correction of PR in TOF patients. © 2017 The Authors. Acta Physiologica published by John Wiley & Sons Ltd on behalf of Scandinavian Physiological Society.

  20. Remote ischemic preconditioning impairs ventricular function and increases infarct size after prolonged ischemia in the isolated neonatal rabbit heart.

    PubMed

    Schmidt, Michael R; Støttrup, Nicolaj B; Michelsen, Marie M; Contractor, Hussain; Sørensen, Keld E; Kharbanda, Rajesh K; Redington, Andrew N; Bøtker, Hans E

    2014-03-01

    Remote ischemic preconditioning (rIPC) reduces myocardial injury in adults and children undergoing cardiac surgery. We compared the effect of rIPC in adult and neonatal rabbits to investigate whether protection against ischemia-reperfusion injury can be achieved in the newborn heart by (1) in vivo rIPC and (2) dialysate from adult rabbits undergoing rIPC. Isolated hearts from newborn and adult rabbits were randomized into 3 subgroups (control, in vivo rIPC, and dialysate obtained from adult, remotely preconditioned rabbits). Remote preconditioning was induced by four 5-minute cycles of lower limb ischemia. Left ventricular (LV) function was assessed using a balloon-tipped catheter, glycolytic flux by tracer kinetics, and infarct size by tetrazolium staining. Isolated hearts underwent stabilization while perfused with standard Krebs-Henseleit buffer (control and in vivo rIPC) or Krebs-Henseleit buffer with added dialysate, followed by global no-flow ischemia and reperfusion. Within the age groups, the baseline LV function was similar in all subgroups. In the adult rabbit hearts, rIPC and rIPC dialysate attenuated glycolytic flux and protected against ischemia-reperfusion injury, with better-preserved LV function compared with that of the controls. In contrast, in the neonatal hearts, the glycolytic flux was lower and LV function was better preserved in the controls than in the rIPC and dialysate groups. In the adult hearts, the infarct size was reduced in the rIPC and dialysate groups compared with that in the controls. In the neonatal hearts, the infarct size was smaller in the controls than in the rIPC and dialysate groups. Remote ischemic preconditioning does not protect against ischemia-reperfusion injury in isolated newborn rabbit hearts and might even cause deleterious effects. Similar adverse effects were induced by dialysate from remotely preconditioned adult rabbits. Copyright © 2014 The American Association for Thoracic Surgery. All rights reserved.

  1. High-frequency periodic sources underlie ventricular fibrillation in the isolated rabbit heart.

    PubMed

    Chen, J; Mandapati, R; Berenfeld, O; Skanes, A C; Jalife, J

    The mechanism(s) underlying ventricular fibrillation (VF) remain unclear. We hypothesized that at least some forms of VF are not random and that high-frequency periodic sources of activity manifest themselves as spatiotemporal periodicities, which drive VF. Twenty-four VF episodes from 8 Langendorff-perfused rabbit hearts were studied using high-resolution video imaging in conjunction with ECG recordings and spectral analysis. Sequential wavefronts that activated the ventricles in a spatially and temporally periodic fashion were identified. In addition, we analyzed the lifespan and dynamics of wavelets in VF, using a new method of phase mapping that enables identification of phase singularity points (PSs), which flank individual wavelets. Spatiotemporal periodicity was found in 21 of 24 episodes. Complete reentry on the epicardial surface was observed in 3 of 24 episodes. The cycle length of discrete regions of spatiotemporal periodicity correlated highly with the dominant frequency of the optical pseudo-ECG (R(2)=0.75) and with the global bipolar electrogram (R(2)=0.79). The lifespan of PSs was short (14.7+/-14.4 ms); 98% of PSs existed for <1 rotation. The mean number of waves entering (6.50+/-0.69) exceeded the mean number of waves that exited our mapping field (4.25+/-0.56; P<0.05). These results strongly suggest that ongoing stable sources are responsible for the majority of the frequency content of VF and therefore play a role in its maintenance. In this model, multiple wavelets resulting from wavebreaks do not appear to be responsible for the sustenance of this arrhythmia, but are rather the consequence of breakup of high-frequency activation from a dominant reentrant source.

  2. Metabolic stress in isolated mouse ventricular myocytes leads to remodeling of t tubules.

    PubMed

    Cheng, Lu-Feng; Wang, Fuzhen; Lopatin, Anatoli N

    2011-11-01

    Cardiac ventricular myocytes possess an extensive t-tubular system that facilitates the propagation of membrane potential across the cell body. It is well established that ionic currents at the restricted t-tubular space may lead to significant changes in ion concentrations, which, in turn, may affect t-tubular membrane potential. In this study, we used the whole cell patch-clamp technique to study accumulation and depletion of t-tubular potassium by measuring inward rectifier potassium tail currents (I(K1,tail)), and inward rectifier potassium current (I(K1)) "inactivation". At room temperatures and in the absence of Mg(2+) ions in pipette solution, the amplitude of I(K1,tail) measured ~10 min after the establishment of whole cell configuration was reduced by ~18%, but declined nearly twofold in the presence of 1 mM cyanide. At ~35°C I(K1,tail) was essentially preserved in intact cells, but its amplitude declined by ~85% within 5 min of cell dialysis, even in the absence of cyanide. Intracellular Mg(2+) ions played protective role at all temperatures. Decline of I(K1,tail) was accompanied by characteristic changes in its kinetics, as well as by changes in the kinetics of I(K1) inactivation, a marker of depletion of t-tubular K(+). The data point to remodeling of t tubules as the primary reason for the observed effects. Consistent with this, detubulation of myocytes using formamide-induced osmotic stress significantly reduced I(K1,tail), as well as the inactivation of inward I(K1). Overall, the data provide strong evidence that changes in t tubule volume/structure may occur on a short time scale in response to various types of stress.

  3. Alterations in echocardiographic left ventricular function after percutaneous coronary stenting in diabetic patients with isolated severe proximal left anterior descending artery stenosis.

    PubMed

    Nabati, Maryam; Taghavi, Morteza; Saffar, Naser; Yazdani, Jamshid; Bagheri, Babak

    There are conflicting theories regarding the use of percutaneous coronary intervention (PCI) of isolated severe proximal left anterior descending (LAD) artery stenosis in place of left internal mammary artery grafting in diabetic patients. The aim of this study was to investigate the effect of PCI on left ventricular function and determine difference between diabetics and non-diabetics. A prospective study was conducted on 50 patients with isolated severe proximal LAD stenosis: 23 diabetic and 27 non-diabetic patients. Successful PCI with everolimus-eluting stents was performed for all of the patients. These patients underwent transthoracic echocardiography within 24h before and 1 month after PCI, and alterations in the left ventricular parameters were compared between the two groups. There was a significant 12% increment in the mitral annular peak systolic velocity (s') (p=0.02), 21% decrement in the trans mitral early filling deceleration time (DT) (p<0.001), 10% decrement in the systolic left ventricular internal dimension (LVIDs) (p=0.002), significant increment in the left ventricular ejection fraction (LVEF) (p=0.004), and significant decrement in the left atrial diameter (p=0.006) in the diabetic patients after performing PCI. Conversely, the non-diabetic patients showed a statistically significant 14% increase in the DT, 6.3% decrease in the s' velocity, 8% increase in the LVIDs, significant increment in the left atrial diameter and no change in LVEF after PCI. Our study demonstrated that everolimus-eluting stents favorably improved the markers of left ventricular systolic and diastolic function in diabetic patients with isolated severe proximal LAD stenosis compared with those of non-diabetic patients with the same condition. Copyright © 2016. Published by Elsevier B.V.

  4. Syndromic non-compaction of the left ventricle: associated chromosomal anomalies.

    PubMed

    Digilio, M C; Bernardini, L; Gagliardi, M G; Versacci, P; Baban, A; Capolino, R; Dentici, M L; Roberti, M C; Angioni, A; Novelli, A; Marino, B; Dallapiccola, B

    2013-10-01

    Non-compaction of the left ventricle (NCLV) is a cardiomyopathy characterized by prominent left ventricular trabeculae and deep intertrabecular recesses. Associated extracardiac anomalies occur in 14-66% of patients of different series, while chromosomal anomalies were reported in sporadic cases. We investigated the prevalence of chromosomal imbalances in 25 syndromic patients with NCLV, using standard cytogenetic, subtelomeric fluorescent in situ hybridization, and array-comparative genomic hybridization (CGH) analyses. Standard chromosome analysis disclosed an abnormality in three (12%) patients, including a 45,X/46,XX mosaic, a 45,X/46,X,i(Y)(p11) mosaic, and a de novo Robertsonian 13;14 translocation in a child affected by hypomelanosis of Ito. Cryptic chromosome anomalies were found in six (24%) cases, including 1p36 deletion in two patients, 7p14.3p14.1 deletion, 18p subtelomeric deletion, 22q11.2 deletion associated with velo-cardio-facial syndrome, and distal 22q11.2 deletion, each in one case. These results recommend accurate clinical evaluation of patients with NCLV, and suggest that chromosome anomalies occur in about one third of syndromic NCLV individuals, without metabolic/neuromuscular disorder. Array-CGH analysis should be included in the diagnostic protocol of these patients, because different submicroscopic imbalances are causally associated with this disorder and can pinpoint candidate genes for this cardiomyopathy. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Effects of propafenone on electrical and mechanical activities of single ventricular myocytes isolated from guinea-pig hearts.

    PubMed Central

    Honjo, H.; Watanabe, T.; Kamiya, K.; Kodama, I.; Toyama, J.

    1989-01-01

    1. The effects of propafenone on the transmembrane action potential and sarcomere shortening during twitch contraction were investigated in single ventricular myocytes isolated from guinea-pig hearts. 2. Propafenone at low concentrations (3-5 x 10(-7) M) slightly lengthened action potential duration (APD), but shortened it at higher concentrations. The shortening of APD was accompanied by an attenuation of sarcomere shortening during twitch contraction. 3. Propafenone (greater than 10(-6) M) caused a concentration-dependent decrease in the maximum upstroke velocity (Vmax) of the action potential. In the presence of propafenone (3 x 10(-6) M), trains of stimuli led to an exponential decline in Vmax. A time constant for the recovery of Vmax from the use-dependent block was 4.8 s. 4. In myocytes treated with propafenone (3 x 10(-6) M), the Vmax of test action potentials preceded by the conditioning clamp pulses to 0 mV was progressively decreased by increasing the duration of single clamp pulse or by increasing the number of multiple brief clamp pulses. 5. These findings suggest that propafenone has use-dependent inhibitory action on the sodium channel by binding to the channel during both activated and inactivated states, and that the unbinding rate is comparable to that of Class-I antiarrhythmic drugs with intermediate kinetics. Propafenone may also have an inhibitory action on calcium and potassium channels. PMID:2758239

  6. The arrhythmogenic transient inward current iTI and related contraction in isolated guinea-pig ventricular myocytes.

    PubMed Central

    Fedida, D; Noble, D; Rankin, A C; Spindler, A J

    1987-01-01

    1. The arrhythmogenic transient inward current, iTI, and contractions were recorded in isolated guinea-pig ventricular myocytes, after exposure to strophanthidin or low external K+ (0.5 mM), using a single-microelectrode voltage-clamp technique and an optical measure of contraction. 2. The inward current, iTI, and after-contraction occurred on repolarization after a depolarizing pre-pulse. Longer pre-pulses to more positive potentials increased the size and reduced the latency of iTI. Oscillatory currents and contractions also occurred during pulses to positive potentials. 3. The voltage dependence of iTI was studied by repolarizing to different potentials after a constant depolarizing pulse. Inward currents preceded after-contractions at all potentials. The iTI was maximal at about -50 mV, diminishing in magnitude at more negative and positive potentials. It remained inward at potentials up to +47 mV. The contraction exhibited a similar voltage dependence. The current-voltage relation varied in the same cell with longer exposure to glycosides. Thus, the voltage dependence of iTI reflected not only that of an underlying ionic mechanism but also the effects of potential on intracellular Ca2+ oscillations which trigger iTI. 4. Uniformity of internal Ca2+ transients was achieved by clamping to different potentials at the peak of an inward current. The iTI remained inward at positive potentials. An inward tail current, seen on repolarizing during iTI at the end of a depolarizing pre-pulse, progressively increased at negative potentials. This voltage dependence may be close to that of the Ca2+-activated inward current responsible for iTI. 5. Replacement of Na+ by Li+ initially increased the magnitude of iTI, but further exposure abolished the inward current, while the after-contractions continued to increase. The potential dependence of iTI was not affected by exposure to zero Na+. Replacement of Ca2+ by Sr2+ also abolished iTI and the after-contraction, but the main

  7. Novel approaches to determine contractile function of the isolated adult zebrafish ventricular cardiac myocyte

    PubMed Central

    Dvornikov, Alexey V; Dewan, Sukriti; Alekhina, Olga V; Pickett, F Bryan; de Tombe, Pieter P

    2014-01-01

    The zebrafish (Danio rerio) has been used extensively in cardiovascular biology, but mainly in the study of heart development. The relative ease of its genetic manipulation may indicate the suitability of this species as a cost-effective model system for the study of cardiac contractile biology. However, whether the zebrafish heart is an appropriate model system for investigations pertaining to mammalian cardiac contractile structure–function relationships remains to be resolved. Myocytes were isolated from adult zebrafish hearts by enzymatic digestion, attached to carbon rods, and twitch force and intracellular Ca2+ were measured. We observed the modulation of twitch force, but not of intracellular Ca2+, by both extracellular [Ca2+] and sarcomere length. In permeabilized cells/myofibrils, we found robust myofilament length-dependent activation. Moreover, modulation of myofilament activation–relaxation and force redevelopment kinetics by varied Ca2+ activation levels resembled that found previously in mammalian myofilaments. We conclude that the zebrafish is a valid model system for the study of cardiac contractile structure–function relationships. PMID:24591576

  8. Intraventricular migration of an isolated fourth ventricular cysticercus following cerebrospinal fluid shunting

    PubMed Central

    Khalid, Saifullah; Obaid, Amber; Sharma, Raman M.; Mahmood, Asad; Narayanasamy, Sabarish

    2016-01-01

    Background: Isolated intraventricular neurocysticercosis (NCC) is less frequently seen and can be missed on plain magnetic resonance imaging (MRI). Three-dimensional constructive interference in steady state (CISS) sequence is an extremely helpful sequence in identifying the lesion but is rarely used routinely. Case Description: Here, we report a case of young male adult who presented with diminution of vision and headache. MRI of the brain revealed hydrocephalus, and on using CISS sequence only, the lesion could be identified in the fourth ventricle. He was treated with medical management, and ventriculoperitoneal shunting of cerebrospinal fluid was done to relieve the hydrocephalus. It resulted in immediate relief with aggravation of headache few days later. Repeat MRI revealed intraventricular migration into the left foramen of monro leading to left lateral ventricle dilatation necessitating endoscopic removal of the lesion. Conclusion: CISS sequence is definitely the sequence of choice in identifying intraventricular NCC. Ventriculoperitoneal shunting can result in the intraventricular migration of the cyst due to sudden decompression necessitating repeat surgery. Endoscopic removal of NCC has a high success rate with limited complications. PMID:28031989

  9. Effect of Late Gadolinium Enhancement on the Recovery of Left Ventricular Systolic Function After Pulmonary Vein Isolation.

    PubMed

    Addison, Daniel; Farhad, Hoshang; Shah, Ravi V; Mayrhofer, Thomas; Abbasi, Siddique A; John, Roy M; Michaud, Gregory F; Jerosch-Herold, Michael; Hoffmann, Udo; Stevenson, William G; Kwong, Raymond Y; Neilan, Tomas G

    2016-09-26

    The factors that predict recovery of left ventricular (LV) systolic dysfunction among patients with atrial fibrillation (AF) are not completely understood. Late gadolinium enhancement (LGE) of the LV has been reported among patients with AF, and we aimed to test whether the presence LGE was associated with subsequent recovery of LV systolic function among patients with AF and LV dysfunction. From a registry of 720 consecutive patients undergoing a cardiac magnetic resonance study prior to pulmonary vein isolation (PVI), patients with LV systolic dysfunction (ejection fraction [EF] <50%) were identified. The primary outcome was recovery of LVEF defined as an EF >50%; a secondary outcome was a combined outcome of subsequent heart failure (HF), admission, and death. Of 720 patients, 172 (24%) had an LVEF of <50% prior to PVI. The mean LVEF pre-PVI was 41±6% (median 43%, range 20% to 49%). Forty-three patients (25%) had LGE (25 [58%] ischemic), and the extent of LGE was 7.5±4% (2% to 19%). During follow-up (mean 42 months), 91 patients (53%) had recovery of LVEF, 68 (40%) had early recurrence of AF, 65 (38%) had late AF, 18 (5%) were admitted for HF, and 23 died (13%). Factors associated with nonrecovery of LVEF were older age, history of myocardial infarction, early AF recurrence, late AF recurrence, and LGE. In a multivariable model, the presence of LGE and any recurrence of AF had the strongest association with persistence of LV dysfunction. Additionally, all patients without recurrence of AF and LGE had normalization of LVEF, and recovery of LVEF was associated with reduced HF admissions and death. In patients with AF and LV dysfunction undergoing PVI, the absence of LGE and AF recurrence are predictors of LVEF recovery and LVEF recovery in AF with associated reduction in subsequent death and heart failure. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  10. Acute Reversal of Phospholamban Inhibition Facilitates the Rhythmic Whole-cell Propagating Calcium Waves in Isolated Ventricular Myocytes

    PubMed Central

    Chan, Yi-Hsin; Tsai, Wei-Chung; Song, Zhen; Ko, Christopher Y.; Qu, Zhilin; Weiss, James N.; Lin, Shien-Fong; Chen, Peng-Sheng; Jones, Larry R.; Chen, Zhenhui

    2015-01-01

    Phospholamban (PLB) inhibits the activity of cardiac sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a). Phosphorylation of PLB during sympathetic activation reverses SERCA2a inhibition, increasing SR Ca2+ uptake. However, sympathetic activation also modulates multiple other intracellular targets in ventricular myocytes (VMs), making it impossible to determine the specific effects of reversal of PLB inhibition on the spontaneous SR Ca2+ release. Therefore, it remains unclear how PLB regulates rhythmic activity in VMs. Here we used the Fab fragment of 2D12, a monoclonal anti-PLB antibody, to test how acute reversal of PLB inhibition affects the spontaneous SR Ca2+ release in normal VMs. Ca2+ sparks and spontaneous Ca2+ waves (SCWs) were recorded in the line-scan mode of confocal microscopy using the Ca2+ fluorescent dye Fluo-4 in isolated permeabilized mouse VMs. Fab, which reverses PLB inhibition, significantly increased the frequency, amplitude, and spatial/temporal spread of Ca2+ sparks in VMs exposed to 50 nM free [Ca2+]. At physiological diastolic free [Ca2+] (100–200 nM), Fab facilitated the formation of whole-cell propagating SCWs. At higher free [Ca2+], Fab increased the frequency and velocity, but decreased the decay time of the SCWs. cAMP had little additional effect on the frequency or morphology of Ca2+ sparks or SCWs after Fab addition. These findings were complemented by computer simulations. In conclusion, acute reversal of PLB inhibition alone significantly increased the spontaneous SR Ca2+ release, leading to the facilitation and organization of whole-cell propagating SCWs in normal VMs. PLB thus plays a key role in subcellular Ca2+ dynamics and rhythmic activity of VMs. PMID:25596331

  11. Unique preferential conduction within the isolated septal substrate in a patient with ventricular tachycardia complicated with non-ischemic dilated cardiomyopathy.

    PubMed

    Watanabe, Masaya; Yokoshiki, Hisashi; Mitsuyama, Hirofumi; Mizukami, Kazuya; Tsutsui, Hiroyuki

    2013-01-01

    We describe the case of a 67-year-old woman with non-ischemic dilated cardiomyopathy who underwent successful radiofrequency catheter ablation for ventricular tachycardia (VT) originated from the isolated ventricular septal substrate. Pacemapping exhibited either left, identical to clinical VT, or right bundle branch block like wide QRS morphology. Time interval from the stimulus to QRS onset (St-QRS) was prolonged at the center of the substrate, while St-QRS at the border was shortened. Difference in the morphology of pacemapping was dependent on whether or not the pacing stimulus could propagate directly into the right ventricle due to the possible intramural conduction disturbance. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. beta-Adrenergic modulation of the inwardly rectifying potassium channel in isolated human ventricular myocytes. Alteration in channel response to beta-adrenergic stimulation in failing human hearts.

    PubMed Central

    Koumi, S; Backer, C L; Arentzen, C E; Sato, R

    1995-01-01

    The beta-adrenergic modulation of the inwardly-rectifying K+ channel (IK1) was examined in isolated human ventricular myocytes using patch-clamp techniques. Isoproterenol (ISO) reversibly depolarized the resting membrane potential and prolonged the action potential duration. Under the whole-cell C1- -free condition, ISO applied via the bath solution reversibly inhibited macroscopic IdK1. The reversal potential of the ISO-sensitive current was shifted by approximately 60 mV per 10-fold change in the external K+ concentration and was sensitive to Ba2+. The ISO-induced inhibition of IK1 was mimicked by forskolin and dibutyrl cAMP, and was prevented by including a cAMP-dependent protein kinase (PKA) inhibitor (PKI) in the pipette solution. In single-channel recordings from cell-attached patches, bath applied ISO could suppress IK1 channels by decreasing open state probability. Bath application of the purified catalytic sub-unit of PKA to inside-out patches also inhibited IK1 and the inhibition could be antagonized by alkaline phosphatase. When beta-adrenergic modulation of IK1 was compared between ventricular myocytes isolated from the failing and the nonfailing heart, channel response to ISO and PKA was significantly reduced in myocytes from the failing heart. Although ISO inhibited IK1 in a concentration-dependent fashion in both groups, a half-maximal concentration was greater in failing (0.12 microM) than in nonfailing hearts (0.023 microM). These results suggest that IK1 in human ventricular myocytes can be inhibited by a PKA-mediated phosphorylation and the modulation is significantly reduced in ventricular myocytes from the failing heart compared to the nonfailing heart. Images PMID:8675658

  13. Calcium-activated non-selective cation channel in ventricular cells isolated from adult guinea-pig hearts.

    PubMed Central

    Ehara, T; Noma, A; Ono, K

    1988-01-01

    1. A class of Ca2+-activated non-selective cation channel was identified in ventricular cells, which were dissociated from adult guinea-pig hearts using collagenase. 2. Under cell-attached conditions the patch electrode filled with a Na+-rich solution recorded no obvious single-channel current at the resting membrane potential. Subsequent superfusion of the ventricular cell with a Na+-free Tyrode solution induced an inward-going single-channel current as well as contracture of the cell. Kinetics of this channel were not affected by varying the membrane potential. 3. Single-channel currents showing a conductance similar to those observed in the cell-attached patches were recorded in isolated inside-out membrane patches when the inner side of the membrane was exposed to a free Ca2+ concentration ([Ca2+]i) higher than 0.3 microM. The slope conductance of the channel was 14.8 +/- 2.9 pS (mean +/- S.D., n = 17) at 20-25 degrees C. 4. The reversal potential examined in the inside-out patch was about 0 mV irrespective of the Na+-rich, K+-rich, Li+-rich or Cs+-rich solutions on either side of the membrane, thereby indicating that the channel was almost equally permeable to these cations. 5. The open probability of the channel was increased by raising [Ca2+]i with the maximum value of 0.93 +/- 0.17 (n = 4) at about 10 microM [Ca2+]i. The dose-response relation was fitted to the saturation kinetics with a Hill coefficient of 3.0 and a half-maximum concentration of 1.2 microM [Ca2+]i. 6. The gating kinetics were complex; both the open and closed time histograms showed at least two exponential components with time constants of 3.8 +/- 1.3 ms and 140 +/- 110 ms for open time and 1.8 +/- 1.1 ms and 14.9 +/- 5.3 ms for closed time (n = 4) at 10 microM [Ca2+]i. Reduction of [Ca2+]i resulted in both a decrease of the time constant of the slow component in the open time histogram and an increase of the two time constants of the closed time histogram. 7. Contribution of the channel

  14. Noncompact dynamical symmetry of a spin-orbit-coupled oscillator

    NASA Astrophysics Data System (ADS)

    Haaker, S. M.; Bais, F. A.; Schoutens, K.

    2014-03-01

    We explain the finite as well as infinite degeneracy in the spectrum of a particular system of spin-1/2 fermions with spin-orbit coupling in three spatial dimensions. Starting from a generalized Runge-Lenz vector, we explicitly construct a complete set of symmetry operators, which span a noncompact SO(3,2) algebra. The degeneracy of the physical spectrum only involves an infinite, so-called singleton representation. In the branch where orbital and spin angular momentum are aligned, the full representation appears, constituting a three-dimensional analog of Landau levels. Antialigning the spin leads to a finite degeneracy due to a truncation of the singleton representation. We conclude the paper by constructing the spectrum generating algebra of the problem.

  15. Role of the T-type calcium channel CaV3.2 in the chronotropic action of corticosteroids in isolated rat ventricular myocytes.

    PubMed

    Maturana, Andrés; Lenglet, Sébastien; Python, Magaly; Kuroda, Shun'ichi; Rossier, Michel F

    2009-08-01

    The mineralocorticoid receptor is involved in the development of several cardiac dysfunctions, including lethal ventricular arrhythmias associated with heart failure or hyperaldosteronism, but the molecular mechanisms responsible for these effects remain to be clarified. Reexpression of low voltage-activated T-type calcium channels in ventricular myocytes together with other fetal genes during cardiac pathologies could confer automaticity to these cells and would represent a pro-arrhythmogenic condition if occurring in vivo. In the present study, we demonstrated that in isolated neonatal rat ventricular myocytes, corticosteroids selectively induced the expression of a particular isoform of T channel, Ca(V)3.2/alpha1H. This response was accompanied by an increase of the Ca(V)3.2 T-type current, identified with the patch clamp technique by its sensitivity to nickel, and a concomitant acceleration of the myocyte spontaneous contractions. Silencing Ca(V)3.2 expression markedly reduced the chronotropic response to steroids. Moreover, modulation of the frequency of cell contractions by different redox agents was independent of channel expression but involved a direct regulation of channel activity. Although oxidants increased both Ca(V)3.2 current amplitude and beating frequency, they decreased L-type channel activity. Reducing agents had the opposite effect on these parameters. In conclusion, the acceleration of ventricular myocyte spontaneous contractions induced by corticosteroids in vitro appears dependent on the expression of the Ca(V)3.2 T channel isoform and modulated by the redox potential of the cells. These results provide a molecular model that could explain the high incidence of arrhythmias observed in patients upon combination of inappropriate activation of the mineralocorticoid receptor and oxidative stress.

  16. Melatonin, given at the time of reperfusion, prevents ventricular arrhythmias in isolated hearts from fructose-fed rats and spontaneously hypertensive rats.

    PubMed

    Diez, Emiliano Raúl; Renna, Nicolás Federico; Prado, Natalia Jorgelina; Lembo, Carina; Ponce Zumino, Amira Zulma; Vazquez-Prieto, Marcela; Miatello, Roberto Miguel

    2013-09-01

    Melatonin reduces reperfusion arrhythmias when administered before coronary occlusion, but in the clinical context of acute coronary syndromes, most of the therapies are administered at the time of reperfusion. Patients frequently have physiological modifications that can reduce the response to therapeutic interventions. This work determined whether acute melatonin administration starting at the moment of reperfusion protects against ventricular arrhythmias in Langendorff-perfused hearts isolated from fructose-fed rats (FFR), a dietary model of metabolic syndrome, and from spontaneous hypertensive rats (SHR). In both experimental models, we confirmed metabolic alterations, a reduction in myocardial total antioxidant capacity and an increase in arterial pressure and NADPH oxidase activity, and in FFR, we also found a decrease in eNOS activity. Melatonin (50 μm) initiated at reperfusion after 15-min regional ischemia reduced the incidence of ventricular fibrillation from 83% to 33% for the WKY strain, from 92% to 25% in FFR, and from 100% to 33% in SHR (P = 0.0361, P = 0.0028, P = 0.0013, respectively, by Fisher's exact test, n = 12 each). Although, ventricular tachycardia incidence was high at the beginning of reperfusion, the severity of the arrhythmias progressively declined in melatonin-treated hearts. Melatonin induced a shortening of the action potential duration at the beginning of reperfusion and in the SHR group also a faster recovery of action potential amplitude. We conclude that melatonin protects against ventricular fibrillation when administered at reperfusion, and these effects are maintained in hearts from rats exposed to major cardiovascular risk factors. These results further support the ongoing translation to clinical trials of this agent.

  17. Effects of phorbol ester on contraction, intracellular pH and intracellular Ca2+ in isolated mammalian ventricular myocytes.

    PubMed Central

    MacLeod, K T; Harding, S E

    1991-01-01

    1. We have investigated the actions of certain phorbol esters on the intracellular pH, intracellular Ca2+ and contractility of isolated rat and guinea-pig cardiac myocytes. Intracellular pH was measured using 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF) and intracellular Ca2+ was measured using Fura-2. 2. Application of the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (also called phorbol 12-myristate 13-acetate) (TPA) (which activates protein kinase C) to rat cardiac myocytes significantly increased cell shortening by 116 +/- 34% (n = 8) (p less than 0.02). The rate of change of cell length during contraction (i.e. +dL/dt) increased from 67.2 +/- 8.7 microns/s to 127.7 +/- 14.1 microns/s (n = 7). The rate of change of cell length during relaxation (-dL/dt) increased from 55.8 +/- 7.4 microns/s to 118.9 +/- 12.1 microns/s (n = 7). Time to peak shortening was unchanged. 3. Application of 4 alpha-phorbol 12,13-didecanoate, which does not activate protein kinase C, did not affect rat myocyte contractility. An insignificant decrease in contractility (by 7.5 +/- 7.5%) was observed (n = 5). The positive inotropic effect of TPA may therefore be evoked through an activation of protein kinase C. 4. In rat myocytes we have measured the changes of pHi and contractility (cell shortening) during an alkalosis and acidosis induced by exposure to and subsequent removal of NH4Cl both in the presence and absence of TPA. Recovery times from an acid load were significantly (p less than 0.05) enhanced by 15.1 +/- 6.9% (n = 13) in the presence of TPA. Recovery times of cell shortening were also more rapid (p less than 0.05) by an average of 59.1 +/- 10.6% (n = 5) in the presence of TPA. Recovery times were unchanged in the presence of 4-phorbol 12,13-didecanoate (which does not activate protein kinase C). 5. Since pHi recovery of an isolated myocyte from an acid load is partially inhibited by the presence of 1 mM-amiloride and inhibited by removing extracellular Na

  18. A rare case of isolated congenital right ventricular inflow obstruction due to the presence of an intraventricular muscular shelf.

    PubMed

    Nanna, Giovanni J; Nanna, Michael G; Muchnik, Danielle; DeRose, Joseph J; Narasimhan, Seshasayee

    2012-01-01

    A 56-year-old man presented with anasarca and a 40-lb weight gain that had occurred over the course of 3 to 4 weeks. He had a history of permanent atrial fibrillation and a congenital anomaly of the right ventricular inflow tract. This defect consisted of a muscular shelf in the right ventricular inflow tract, which encased the tricuspid subvalvular apparatus in such a manner that it created tricuspid stenosis. The clinical consequences of this anatomic and hemodynamic situation were a massively dilated right atrium, permanent atrial fibrillation, and clinical evidence of right-sided heart failure, including fluid retention and ascites. The patient underwent surgical resection of the muscular shelf, which was followed by progressive resolution of the ascites and fluid retention.

  19. Comparison of Na(+)/Ca(2+) exchanger current and of its response to isoproterenol between acutely isolated and short-term cultured adult ventricular myocytes.

    PubMed

    Pabbathi, V K; Zhang, Y H; Mitcheson, J S; Hinde, A K; Perchenet, L; Arberry, L A; Levi, A J; Hancox, J C

    2002-09-20

    The Na(+)/Ca(2+) exchanger protein is present in the cell membrane of many tissue types and plays key roles in Ca(2+) homeostasis, excitation-contraction coupling, and generation of electrical activity in the heart. The use of adult ventricular myocyte cell culture is important to molecular biological approaches to study the roles and modulation of the cardiac Na(+)/Ca(2+) exchanger. Therefore, we characterised the functional expression of the exchanger in adult guinea-pig ventricular myocytes maintained in short-term culture (for 4 days) and compared the response of ionic current (I(NaCa)) carried by the exchanger from acutely isolated and Day 4 cells to beta-adrenoceptor activation with isoproterenol (ISO). Functional activity of the exchanger was assessed by measuring I(NaCa) using whole cell patch clamp, under selective recording conditions. I(NaCa) amplitude measured at both +60 and -100mV declined significantly by Day 1 of cell culture, showing a further small decline by Day 4. However, cell surface area (assessed by measuring membrane capacitance) also declined over this time-frame. I(NaCa) normalised to membrane capacitance (I(NaCa) density) did not differ significantly between acutely isolated and cells cultured for 4 days. However, although ISO (1 microM) increased I(NaCa) in acutely isolated myocytes, it exerted no significant effect on I(NaCa) from Day 4 cells. This was not due to an inherent inability of these cells to respond to ISO, as L-type calcium current amplitude from Day 4 cells was increased by ISO to a similar extent as that from acutely isolated cells. Our data suggest that the functional expression of the Na/Ca exchanger is well maintained during short-term culture of adult ventricular myocytes. The lack of response to ISO of I(NaCa) from Day 4 cells suggests: (a) that, despite a well-maintained I(NaCa) density, cultured adult myocytes may not necessarily be suitable for studies of exchanger modulation by some agonists and (b) that there

  20. Aeroacoustic theory for noncompact wing-gust interaction

    NASA Technical Reports Server (NTRS)

    Martinez, R.; Widnall, S. E.

    1981-01-01

    Three aeroacoustic models for noncompact wing-gust interaction were developed for subsonic flow. The first is that for a two dimensional (infinite span) wing passing through an oblique gust. The unsteady pressure field was obtained by the Wiener-Hopf technique; the airfoil loading and the associated acoustic field were calculated, respectively, by allowing the field point down on the airfoil surface, or by letting it go to infinity. The second model is a simple spanwise superposition of two dimensional solutions to account for three dimensional acoustic effects of wing rotation (for a helicopter blade, or some other rotating planform) and of finiteness of wing span. A three dimensional theory for a single gust was applied to calculate the acoustic signature in closed form due to blade vortex interaction in helicopters. The third model is that of a quarter infinite plate with side edge through a gust at high subsonic speed. An approximate solution for the three dimensional loading and the associated three dimensional acoustic field in closed form was obtained. The results reflected the acoustic effect of satisfying the correct loading condition at the side edge.

  1. Closure of aorto-right ventricular tunnel with Amplatzer duct occluder II.

    PubMed

    Vijayalakshmi, I B; Narasimhan, Chitra; Agarwal, Ashish

    2013-04-01

    Aorto-right ventricular tunnel (ARVT) is a very rare, congenital, abnormal extracardiac channel that connects the ascending aorta at or above the sinotubular junction to the cavity of the right ventricle. Only 16 cases have been reported thus far in the English literature. We report the first transcatheter closure of ARVT with the Amplatzer duct occluder II in an infant, with both coronary arteries arising from the left coronary sinus and with biventricular apical non-compaction.

  2. Interaction of a Transapical Miniaturized Ventricular Assist Device With the Left Ventricle: Hemodynamic Evaluation and Visualization in an Isolated Heart Setup.

    PubMed

    Granegger, Marcus; Aigner, Philipp; Haberl, Thomas; Mahr, Stephane; Tamez, Daniel A; Graham, Joel; Nunez, Nathalie J; Schima, Heinrich; Moscato, Francesco

    2016-12-01

    New left ventricular assist devices (LVADs) offer both important advantages and potential hazards. VAD development requires better and expeditious ways to identify these advantages and hazards. We validated in an isolated working heart the hemodynamic performance of an intraventricular LVAD and investigated how its outflow cannula interacted with the aortic valve. Hearts from six pigs were explanted and connected to an isolated working heart setup. A miniaturized LVAD was implanted within the left ventricle (tMVAD, HeartWare Inc., Miami Lakes, FL, USA). In four experiments blood was used to investigate hemodynamics under various loading conditions. In two experiments crystalloid perfusate was used, allowing visualization of the outflow cannula within the aortic valve. In all hearts the transapical miniaturized ventricular assist device (tMVAD) implantation was successful. In the blood experiments hemodynamics similar to those observed clinically were achieved. Pump speeds ranged from 9 to 22 krpm with a maximum of 7.6 L/min against a pressure difference between ventricle and aorta of ∼50 mm Hg. With crystalloid perfusate, central positioning of the outflow cannula in the aortic root was observed during full and partial support. With decreasing aortic pressures the cannula tended to drift toward the aortic root wall. The tMVAD could unload the ventricle similarly to LVADs under conventional cannulation. Aortic pressure influenced central positioning of the outflow cannula in the aortic root. The isolated heart is a simple, accessible evaluation platform unaffected by complex reactions within a whole, living animal. This platform allowed detection and visualization of potential hazards. Copyright © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  3. Electrophysiological effects of OPC-88117, a new antiarrhythmic agent on papillary muscles and single ventricular myocytes isolated from guinea-pig hearts.

    PubMed Central

    Toyama, J.; Kodama, I.; Honjo, H.; Kamiya, K.

    1989-01-01

    1. The effects of OPC-88117, a new antiarrhythmic agent, on transmembrane action potentials were examined in right ventricular papillary muscles and in single ventricular myocytes isolated from guinea-pig hearts. 2. In papillary muscles, OPC-88117 above 3 x 10(-6) M caused a dose-dependent prolongation of action potential duration (APD). 3. OPC-88117 above 3 x 10(-5) M caused a significant decrease in the maximum upstroke velocity (Vmax) of the action potential without affecting the resting membrane potential. The inhibition of Vmax was enhanced at higher stimulation frequencies. 4. In the presence of OPC-88117, trains of stimuli at rates greater than or equal to 1.0 Hz led to a use-dependent inhibition of Vmax with rapid onset. The time constant for the recovery of Vmax from the use-dependent block was 456 ms. 5. The curves relating membrane potential and Vmax were shifted by OPC-88117 to the direction of more negative potentials (9 mV at 10(-4) M). 6. In single ventricular myocytes treated with OPC-88117 (1-3 x 10(-4) M), the Vmax of test action potentials preceded by conditioning clamp pulses to 0 mV was decreased progressively as the clamp pulse duration was prolonged. 7. These findings suggest that the primary electrophysiological effect of OPC-88117 on the cardiac muscle cell is prolongation of APD (Class III action) and that at high concentrations, it may also possess a lignocaine-like sodium channel inhibitory effect (Class I action). PMID:2553186

  4. Low oxygen tension induces positive inotropy and decreases a(i)Na in isolated guinea-pig cardiac ventricular papillary muscles.

    PubMed

    Jao, M J; Yang, J M

    1998-06-30

    Effects of low oxygen on contractile force, intracellular Na+ activity (aiNa), and action potential were simultaneously measured in isolated guinea-pig ventricular papillary muscles. Reduction of oxygen from control 488 to 150 mmHg biphasically increased and decreased the twitch tension, and decreased aiNa in muscles driven at 60 beats/min. The action potential duration (APD) was decreased but the maximum rate of upstroke (Vmax) was increased. In control, 1 microM epinephrine significantly increased the the action potential amplitude and twitch tension with decreases in the time to twitch peak (TTP), time for 50% relaxation (RT50), and aiNa. After exposure to low oxygen for 10 min, with twitch tension elevated and TTP and RT90 increased, 1 microM epinephrine significantly increased the twitch tension and Vmax, and decreased the APD and aiNa. Pretreatment with reserpine inhibited the twitch tension, both at control and in the presence of epinephrine. But changes of action potential and aiNa in response to low oxygen and epinephrine were similar to those in control. Our results indicate that the isolated guinea-pig ventricular muscle needs a high oxygen tension to maintain a normal contractile function. Reduction of oxygen deteriorates the electrical and mechanical activities, most likely, by a coaxial graded hypoxia. The decreased aiNa, not associated with endogenous catecholamines, suggests that the activity of the Na(+)-K+ pump can be maintained in the superficial muscle cells despite of core-central hypoxia.

  5. Noncompaction cardiomyopathy: The role of advanced multimodality imaging techniques in diagnosis and assessment.

    PubMed

    Chebrolu, Lakshmi H; Mehta, Anjlee M; Nanda, Navin C

    2017-02-01

    Noncompaction cardiomyopathy (NCCM) is a unique cardiomyopathy with a diverse array of genotypic and phenotypic manifestations. Its hallmark morphology consists of a bilayered myocardium with a compact epicardial layer and prominent trabeculations that comprise the noncompacted endocardial layer. The controversial diagnostic criteria for NCCM have been frequently discussed in the literature. This review touches on those diagnostic criteria, delves further into the evolving use of advanced imaging techniques within the major imaging modalities (echocardiography, computed tomography, and cardiac magnetic resonance imaging), and proposes an alternative algorithm incorporating these techniques for aiding with the diagnosis of NCCM.

  6. Invariant Differential Operators for Non-Compact Lie Groups: Euclidean Jordan Groups or Conformal Lie Groups

    NASA Astrophysics Data System (ADS)

    Dobrev, V. K.

    2013-01-01

    In the present paper we continue the project of systematic construction of invariant differential operators for non-compact semisimple Lie groups. Our starting points is the class of algebras, which we call 'conformal Lie algebras' (CLA), which have very similar properties to the conformal algebras of Minkowski space-time, though our aim is to go beyond this class in a natural way. For this we introduce the new notion of parabolic relation between two non-compact semisimple Lie algebras Script G and Script G' that have the same complexification and possess maximal parabolic subalgebras with the same complexification.

  7. Oscillator-like unitary representations of non-compact groups with a jordan structure and the non-compact groups of supergravity

    NASA Astrophysics Data System (ADS)

    Günaydin, M.; Saçlioglu, C.

    1982-06-01

    We give a general bosonic construction of oscillator-like unitary irreducible representations (UIR) of non-compact groups whose coset spaces with respect to their maximal compact subgroups are Hermitian symmetric. With the exception of E7(7), they include all the non-compact invariance groups of extended supergravity theories in four dimensions. These representations have the remarkable property that each UIR is uniquely determined by an irreducible representation of the maximal compact subgroup. We study the connection between our construction, the Hermitian symmetric spaces and the Tits-Koecher construction of the Lie algebras of corresponding groups. We then give the bosonic construction of the Lie algebra of E 7(7) in SU(8), SO(8) and U(7) bases and study its properties. Application of our method to E 7(7) leads to reducible unitary representations.

  8. Ventricular tachycardia

    MedlinePlus

    ... prevented by treating heart problems and avoiding certain medicines. Alternative Names Wide-complex tachycardia; V tach; Tachycardia - ventricular Images Implantable cardioverter-defibrillator ... Ventricular arrhythmias. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap ...

  9. Incidence and natural history of neonatal isolated ventricular septal defects: Do we know everything? A 6-year single-center Italian experience follow-up.

    PubMed

    Cresti, Alberto; Giordano, Raffaele; Koestenberger, Martin; Spadoni, Isabella; Scalese, Marco; Limbruno, Ugo; Falorini, Susanna; Stefanelli, Stefania; Picchi, Andrea; De Sensi, Francesco; Malandrino, Angela; Cantinotti, Massimiliano

    2017-08-30

    Despite ventricular septal defects (VSDs) are the most common congenital heart diseases (CHDs) in the neonatal period, their incidence and natural history are still debated and their follow-up and management strategies remain controversial. Our aim was to evaluate the incidence and natural history of isolated VSDs. From January 1996 to December 2015 all neonates with a CHD suspicion were referred to the Cardiological Department of Grosseto Misericordia Hospital. Only newborns with confirmed isolated VSD were enrolled in this study and followed for 6 years. Our 343 newborns with an isolated VSD (incidence of 10.45/1000/births) account for 64% of all detected CHDs. VSDs location were as follows: muscular (73.8%), perimembranous (11.3%), inlet (1%), and outlet (0.8%). Of the located VSDs, 90% were small, 7.5% moderate, and 2.5% large, respectively. Spontaneous closure was observed in 96 (29.2%) of the VSD patients at 6-month, 198 (60.2%) at 1-year, 261 (79.3%) at 2-year, and in 302 (91.8%) at 6-year follow-up. Risk factors for defect persistence were a perimembranous location (P = .001; HR: 0.508, CI: 0.342-0.755), detection of multiple defects (P = .043; HR: 0.728, CI: 0.536-0.990), and male gender (P < .048; HR: 0.783, CI: 0.615-0.998), respectively. We here provide an incidence and natural history of neonatal isolated VSDs in a neonatal Caucasian population. These data may be useful for the development of expert consensus/standard recommendation guidelines for the follow-up and VSD management, data that are currently lacking. © 2017 Wiley Periodicals, Inc.

  10. On a Mathematical Model with Noncompact Boundary Conditions Describing Bacterial Population

    NASA Astrophysics Data System (ADS)

    Boulanouar, Mohamed

    2013-04-01

    In this work, we are concerned with the well-posedness of a mathematical model describing a maturation-velocity structured bacterial population. Each bacterium is distinguished by its degree of maturity and its maturation velocity. The bacterial mitosis is mathematically described by noncompact boundary conditions. We show that the mathematical model is governed by a positive strongly continuous semigroup.

  11. Invariant differential operators for non-compact Lie groups: Summary of su(4,4) multiplets

    NASA Astrophysics Data System (ADS)

    Dobrev, V. K.

    2017-03-01

    The present paper is part of the project of systematic construction of invariant differential operators of noncompact semisimple Lie algebras. Here we give a summary of all multiplets containing physically relevant representations including the minimal ones for the algebra su(4, 4). Due to the recently established parabolic relations the results are valid also for the algebras sl(8, R) and su*(8)

  12. Usefulness of plasma brain natriuretic peptide measurement and tissue Doppler imaging in identifying isolated left ventricular diastolic dysfunction without heart failure.

    PubMed

    Goto, Toshihiko; Ohte, Nobuyuki; Wakami, Kazuaki; Asada, Kaoru; Fukuta, Hidekatsu; Mukai, Seiji; Tani, Tomomitsu; Kimura, Genjiro

    2010-07-01

    Left ventricular (LV) diastolic dysfunction carries a substantial risk for the subsequent development of heart failure and reduced survival, even when it is asymptomatic. Plasma brain natriuretic peptide (BNP) level and tissue Doppler imaging indexes provide powerful incremental assessment of LV diastolic function. Accordingly, the aim of this study was to clarify whether these methodologies could identify LV diastolic dysfunction without heart failure in 280 patients with preserved LV ejection fractions (> or =50%) who underwent echocardiography and cardiac catheterization for the evaluation of coronary artery disease. Patients were classified into 2 groups, those with diastolic dysfunction (tau > or =48 ms; n = 91) and those with normal diastolic function (tau <48 ms; n = 189). Plasma BNP > or =22.4 pg/ml, an unexpectedly low value, had sensitivity of 74.7% and specificity of 60.8% for identifying isolated LV diastolic dysfunction; the combined use of BNP > or =22.4 pg/mL and mitral annular velocity during early diastole <7.4 cm/s had relatively low sensitivity of 44.0% but high specificity of 86.8%. In conclusion, using plasma BNP level and with the combination of BNP level and mitral annular velocity during early diastole, invasively proved isolated LV diastolic dysfunction without heart failure could be identified in patients with coronary artery disease.

  13. Long-Term Follow-Up of Isolated Epicardial Left Ventricular Lead Implant Using a Minithoracotomy Approach for Cardiac Resynchronization Therapy.

    PubMed

    McALOON, Christopher J; Anderson, Benjamin M; Dimitri, Wadih; Panting, Jonathan; Yusuf, Shamil; Bhudia, Sunil K; Osman, Faizel

    2016-10-01

    Transvenous left ventricular (LV) lead placement for cardiac resynchronization therapy is unsuccessful in 5-10% of reported cases. These patients may benefit from isolated surgical placement of an epicardial LV lead via minithoracotomy approach. To evaluate the success of this approach at long-term follow-up. Retrospective evaluation of all consecutive patients undergoing isolated epicardial LV lead placement after failed transvenous attempt over a 6-year period. Data collected on baseline parameters, procedural details, and outcome at follow-up (hospital stay, complications, mortality, and clinical response). Forty-two patients underwent epicardial lead implant. Five died within 1 year (11.9%): two (4.8%) died within 30-days post op (one from intraoperative hemorrhage, the other from multiple organ failure); 39 (95.1%) were admitted to the high dependency unit and transferred to the ward <24 hours. Median hospital stay was 3.4 ± 1.9 days. The overall complication rate was 17.5% (n = 7): 15.0% (n = 6) short term and 2.5% (n = 1) long term; these included three (7.5%) LV noncapture events all treated with reprogramming. There were two (5.0%) wound infections requiring oral antibiotics and two (5.0%) device infections requiring intravenous antibiotics (one had device resiting, the other developed septic shock requiring intensive care admission). Assessment of clinical response was possible in 34 (81.0%) at follow-up: 21 (61.8%) were responders and 13 (28.2%) nonresponders with no significant differences between these groups; no clinical predictors of response were identified. Isolated epicardial LV lead implant using minithoracotomy is relatively safe and effective at successful LV pacing. Response rate and postoperative recovery at long-term follow-up are reasonable in these high-risk patients. © 2016 Wiley Periodicals, Inc.

  14. Low sodium inotropy is accompanied by diastolic Ca2+ gain and systolic loss in isolated guinea-pig ventricular myocytes

    PubMed Central

    Même, William; O'Neill, S C; Eisner, D A

    2001-01-01

    We measured sarcolemmal Ca2+ fluxes responsible for the positive inotropic effects of solutions with reduced Na+ concentration in voltage-clamped guinea-pig ventricular myocytes; intracellular Ca2+ concentration ([Ca2+]i) was measured with Indo-1. Reduction of external Na+ concentration by 50 % (to 67 mM) produced an increase in systolic [Ca2+]i accompanied by a decrease in Ca2+ entry via the L-type Ca2+ current. With reduced Na+ concentration, there was an initial decrease in the Na+–Ca2+ exchange current on repolarization followed by an increase to greater than control. We attribute this initial decrease to a decrease in the Na+ gradient and the subsequent increase to a fall in intracellular Na+ concentration and increase in systolic [Ca2+]i. The decreased L-type Ca2+ current and increased Ca2+ efflux on Na+–Ca2+ exchange resulted in a calculated systolic loss of Ca2+. The calculated systolic loss of Ca2+ was accompanied by a measured increase in sarcoplasmic reticulum (SR) Ca2+ content. Reduction of the external Na+ concentration also produced an outward shift of holding current which was blocked by Ni2+. This is taken to represent Ca2+ influx via Na+–Ca2+ exchange. When diastolic influx is taken into account, the observed gain in SR Ca2+ content can be predicted. The measurements show that, in reduced Na+, much of the entry of Ca2+ into the cell occurs during diastole (via Na+–Ca2+ exchange) rather than in systole (via the L-type Ca2+ current). PMID:11158278

  15. Transoesophageal echocardiography for prediction of postoperative atrial fibrillation after isolated aortic valve replacement: two-dimensional speckle tracking for intraoperative assessment of left ventricular longitudinal strain.

    PubMed

    Hu, Jia; Peng, Ling; Qian, Hong; Li, Ya-jiao; Meng, Wei; Xiao, Zheng-hua; Zhao, Jing Janice; Hu, Jonathan Zhao; Zhang, Er-yong

    2015-05-01

    Recent studies suggested association between impaired left ventricular long-axis function and arrhythmic events early after open heart surgery. This prospective study investigated the predictive value of a depressed intraoperative global longitudinal strain (GLS) for postoperative atrial fibrillation after isolated aortic valve replacement in patients with preserved ejection fraction. A total of 107 patients with ejection fraction ≥50% and moderate-to-severe aortic stenosis undergoing isolated aortic valve replacement were enrolled. All patients underwent intraoperative transoesophageal echocardiography before surgical incision (T1) and after closure of the sternotomy (T2) with semiautomated measurement of GLS, and were followed for the occurrence of postoperative atrial fibrillation during the hospitalization. The incidence of postoperative atrial fibrillation was 37/107 (34.6%). Patients with postoperative atrial fibrillation were associated with increased length of hospitalization and a higher risk of low cardiac output syndrome and pulmonary complications. On univariate analysis, significant risk factors associated with postoperative atrial fibrillation were E/e' ratio, left atrial volume index (LAVi), GLST2 and ΔGLS%. On multivariable analysis, GLST2 (odds ratio: 1.21; 95% confidence interval (CI): 1.06-1.56, P = 0.031) and ΔGLS% (odds ratio: 3.66; 95% CI: 1.85-6.79, P = 0.001) were independent predictors of postoperative atrial fibrillation. The best cut-off values for the prediction were GLST2 >-12.75% and ΔGLS% >19.50%, the latter of which had incremental predictive value for postoperative atrial fibrillation. A significant reduction of intraoperative GLS provides independent information for predicting postoperative atrial fibrillation in patients undergoing aortic valve replacement, and may help to identify patients who are most likely to benefit from targeted prophylaxis. © The Author 2014. Published by Oxford University Press on behalf of the

  16. Acquired noncompaction associated with coronary heart disease and myopathy.

    PubMed

    Finsterer, Josef; Stöllberger, Claudia; Bonner, Elisabeth

    2010-01-01

    In a 77-year-old man with a history of arterial hypertension, coronary heart disease, dilative cardiomyopathy, mitral and tricuspid insufficiency, arteriovenous block III, implantation of a pacemaker, atrial fibrillation, and heart failure, left ventricular hypertrabeculation (LVHT) was detected on transthoracic echocardiography during hospitalization for worsening heart failure. Revision of previous echocardiography did not show LVHT in any of the previous investigations why LVHT was interpreted as acquired. The additional presentation with bilateral ptosis, madarosis (absent eyelashes), bilateral hypoacusis, sore neck muscles, absent tendon reflexes, weakness for foot extension, ataxic stance, and recurrently elevated creatine kinase with normal troponin-T suggested a metabolic myopathy. Autopsy after death resulting from intractable heart failure, 17 months later, confirmed severe coronary heart disease and LVHT in the apex. The case confirms that LVHT may be acquired in single cases with neuromuscular disease and may represent an adaptive mechanism of an impaired myocardium. Copyright 2010 Elsevier Inc. All rights reserved.

  17. Regulation by endothelin-1 of Na+-Ca2+ exchange current (I(NaCa)) from guinea-pig isolated ventricular myocytes.

    PubMed

    Zhang, Y H; James, A F; Hancox, J C

    2001-11-01

    The cardiac Na+-Ca2+ exchanger participates in Ca homeostasis, and Na+-Ca2+ exchanger-mediated ionic current (I(NaCa)) also contributes to the regulation of cardiac action potential duration. Moreover, I(NaCa) can contribute to arrhythmogenesis under conditions of cellular Ca overload. Although it has been shown that the peptide hormone endothelin-1 (ET-1) can phosphorylate the cardiac Na+-Ca2+ exchanger via protein kinase C (PKC), little is known about the effect of ET-1 on I(NaCa). In order to examine the effects of ET-1 on I(NaCa), whole-cell patch clamp measurements were made at 378C from guinea-pig isolated ventricular myocytes. With major interfering currents inhibited, I(NaCa) was measured as the current sensitive to nickel (Ni; 10mM) during a descending voltage ramp. ET-1 (10 nM) significantly increased I(NaCa) ( approximately 2-fold at -100 mV). Application of a PKC activator (PMA; 1mM: phorbol 12-myristate 13-acetate), mimicked the effect of ET-1. In contrast, the PKC inhibitor chelerythrine (CLT, 1mM) abolished the stimulatory effect of ET-1. An inactive phorbol ester, 4-alpha-phorbol-12,13-didecanoate (4a-PDD, 1mM) had no effect on I(NaCa). Collectively, these data indicate that ET-1 activated I(NaCa) through a PKC-dependent pathway. In additional experiments, isoprenaline (ISO; which has also been reported to activate I(NaCa) ) was applied. The increase in I(NaCa) density with ISO (1mM) was similar to that induced by ET-1 (10nM). When I(NaCa) was pre-stimulated by ET-1, application of ISO elicited no further increase in current and vice versa. ISO also had no additional effect on I(NaCa) when the cells were pretreated with PMA. Application of CLT did not alter the response of I(NaCa) to ISO. We conclude that ET-1 stimulated ventricular I(NaCa) via a PKC-dependent mechanism under our recording conditions. Concentrations of ET-1 and ISO that stimulated I(NaCa) to similar extents when applied separately were not additive when co-applied. The lack of

  18. [Perioperative treatment of a pregnant woman with recent cerebral infarction secondary to noncompaction cardiomyopathy].

    PubMed

    Fernández Sánchez, L J; Pérez González, R; Guasch Arévalo, E; Martín Reyes, R; Gilsanz Rodríguez, F

    2006-12-01

    Recent-onset noncompaction of the myocardium is a rare but serious entity with uncertain prognosis. Cerebral infarction is among the forms of presentation, and pregnancy and hypercoagulability increase risk. We report the case of a pregnant woman brought to the emergency department with ischemic cerebral infarction. Investigation demonstrated the cause to be cardiac embolism, and noncompaction of the myocardium was diagnosed. She was stabilized and a few days later underwent elective cesarean section under general anesthesia. Surgery and postoperative recovery were uneventful, and she was transferred for rehabilitation. Myocardial injury and progression to cerebrovascular accident must be prevented in such cases; the patient must be stabilized and antiplatelet and/or anticoagulant therapy initiated before surgery. Hemodynamic stability must be maintained throughout the perioperative period and neonatal depression avoided after delivery. Various approaches are available to be adapted to the patient's situation.

  19. Development of a noncompact source theory with applications to helicopter rotors

    NASA Technical Reports Server (NTRS)

    Farassat, F.; Brown, T. J.

    1976-01-01

    A new formulation for determining the acoustic field of moving bodies, based on acoustic analogy, is derived. The acoustic pressure is given as the sum of two integrals, one of which has a derivative with respect to time. The integrands are functions of the normal velocity and surface pressure of the body. A computer program based on this formulation was used to calculate acoustic pressure signatures for several helicoptor rotors from experimental surface pressure data. Results are compared with those from compact source calculations. It is shown that noncompactness of steady sources on the rotor can account for the high harmonics of the pressure system. Thickness noise is shown to be a significant source of sound, especially for blunt airfoils in regions where noncompact source theory should be applied.

  20. Development of a noncompact source theory with applications to helicopter rotors

    NASA Technical Reports Server (NTRS)

    Farassat, F.; Brown, T. J.

    1976-01-01

    A new formulation for determining the acoustic field of moving bodies, based on acoustic analogy, is derived. The acoustic pressure is given as the sum of two integrals, one of which has a derivative with respect to time. The integrands are functions of the normal velocity and surface pressure of the body. A computer program based on this formulation was used to calculate acoustic pressure signatures for several helicoptor rotors from experimental surface pressure data. Results are compared with those from compact source calculations. It is shown that noncompactness of steady sources on the rotor can account for the high harmonics of the pressure system. Thickness noise is shown to be a significant source of sound, especially for blunt airfoils in regions where noncompact source theory should be applied.

  1. Equidistribution of Zeros of Holomorphic Sections in the Non-compact Setting

    NASA Astrophysics Data System (ADS)

    Dinh, Tien-Cuong; Marinescu, George; Schmidt, Viktoria

    2012-07-01

    We consider tensor powers L N of a positive Hermitian line bundle ( L, h L ) over a non-compact complex manifold X. In the compact case, B. Shiffman and S. Zelditch proved that the zeros of random sections become asymptotically uniformly distributed as N→∞ with respect to the natural measure coming from the curvature of L. Under certain boundedness assumptions on the curvature of the canonical line bundle of X and on the Chern form of L we prove a non-compact version of this result. We give various applications, including the limiting distribution of zeros of cusp forms with respect to the principal congruence subgroups of SL 2(ℤ) and to the hyperbolic measure, the higher dimensional case of arithmetic quotients and the case of orthogonal polynomials with weights at infinity. We also give estimates for the speed of convergence of the currents of integration on the zero-divisors.

  2. Heat-kernel expansion on noncompact domains and a generalized zeta-function regularization procedure

    SciTech Connect

    Cognola, Guido; Elizalde, Emilio; Zerbini, Sergio

    2006-08-15

    Heat-kernel expansion and zeta function regularization are discussed for Laplace-type operators with discrete spectrum in noncompact domains. Since a general theory is lacking, the heat-kernel expansion is investigated by means of several examples. It is pointed out that for a class of exponential (analytic) interactions, generically the noncompactness of the domain gives rise to logarithmic terms in the heat-kernel expansion. Then, a meromorphic continuation of the associated zeta function is investigated. A simple model is considered, for which the analytic continuation of the zeta function is not regular at the origin, displaying a pole of higher order. For a physically meaningful evaluation of the related functional determinant, a generalized zeta function regularization procedure is proposed.

  3. Contribution of sarcolemmal sodium-calcium exchange and intracellular calcium release to force development in isolated canine ventricular muscle

    PubMed Central

    1992-01-01

    The aim of this work was to determine the relationship between peak twitch amplitude and sarcoplasmic reticulum (SR) Ca2+ content during changes of stimulation frequency in isolated canine ventricle, and to estimate the extent to which these changes were dependent upon sarcolemmal Na(+)-Ca2+ exchange. In physiological [Na+]o, increased stimulation frequency in the 0.2-2-Hz range resulted in a positive inotropic effect characterized by an increase in peak twitch amplitude and a decrease in the duration of contraction, measured as changes in isometric force development or unloaded cell shortening in intact muscle and isolated single cells, respectively. Action potentials recorded from single cells indicated that the inotropic effect was associated with a progressive decrease of action potential duration and a marked reduction in average time spent by the cell near the resting potential during the stimulus train. The frequency-dependent increase of peak twitch force was correlated with an increase of Ca2+ uptake into and release from the SR. This was estimated indirectly using the phasic contractile response to rapid (less than 1 s) lowering of perfusate temperature from 37 degrees C to 0-2 degrees C and changes of twitch amplitude resulting from perturbations in the pattern of electrical stimulation. Lowering [Na+]o from 140 to 70 mM resulted in an increase of contractile strength, which was accompanied by a similar increase of apparent SR Ca2+ content, both of which could be abolished by exposure to ryanodine (1 x 10(-8) M), caffeine (3 x 10(-3) M), or nifedipine (2 x 10(-6) M). Increased stimulation frequency in 70 mM [Na+]o resulted in a negative contractile staircase, characterized by a graded decrease of peak isometric force development or unloaded cell shortening. SR Ca2+ content estimated under identical conditions remained unaltered. Rate constants derived from mechanical restitution studies implied that the depressant effect of increased stimulation

  4. A noncompact Weyl-Einstein-Yang-Mills model: A semiclassical quantum gravity

    NASA Astrophysics Data System (ADS)

    Dengiz, Suat

    2017-08-01

    We construct and study perturbative unitarity (i.e., ghost and tachyon analysis) of a 3 + 1-dimensional noncompact Weyl-Einstein-Yang-Mills model. The model describes a local noncompact Weyl's scale plus SU(N) phase invariant Higgs-like field,conformally coupled to a generic Weyl-invariant dynamical background. Here, the Higgs-like sector generates the Weyl's conformal invariance of system. The action does not admit any dimensionful parameter and genuine presence of de Sitter vacuum spontaneously breaks the noncompact gauge symmetry in an analogous manner to the Standard Model Higgs mechanism. As to flat spacetime, the dimensionful parameter is generated within the dimensional transmutation in quantum field theories, and thus the symmetry is radiatively broken through the one-loop Effective Coleman-Weinberg potential. We show that the mere expectation of reducing to Einstein's gravity in the broken phases forbids anti-de Sitter space to be its stable vacua. The model is unitary in de Sitter and flat vacua around which a massless graviton, N2 - 1 massless scalar bosons, N massless Dirac fermions, N2 - 1 Proca-type massive Abelian and non-Abelian vector bosons are generically propagated.

  5. The calcium-independent transient outward potassium current in isolated ferret right ventricular myocytes. I. Basic characterization and kinetic analysis

    PubMed Central

    1993-01-01

    Enzymatically isolated myocytes from ferret right ventricles (12-16 wk, male) were studied using the whole cell patch clamp technique. The macroscopic properties of a transient outward K+ current I(to) were quantified. I(to) is selective for K+, with a PNa/PK of 0.082. Activation of I(to) is a voltage-dependent process, with both activation and inactivation being independent of Na+ or Ca2+ influx. Steady-state inactivation is well described by a single Boltzmann relationship (V1/2 = -13.5 mV; k = 5.6 mV). Substantial inactivation can occur during a subthreshold depolarization without any measurable macroscopic current. Both development of and recovery from inactivation are well described by single exponential processes. Ensemble averages of single I(to) channel currents recorded in cell-attached patches reproduce macroscopic I(to) and indicate that inactivation is complete at depolarized potentials. The overall inactivation/recovery time constant curve has a bell-shaped potential dependence that peaks between -10 and -20 mV, with time constants (22 degrees C) ranging from 23 ms (-90 mV) to 304 ms (-10 mV). Steady-state activation displays a sigmoidal dependence on membrane potential, with a net aggregate half- activation potential of +22.5 mV. Activation kinetics (0 to +70 mV, 22 degrees C) are rapid, with I(to) peaking in approximately 5-15 ms at +50 mV. Experiments conducted at reduced temperatures (12 degrees C) demonstrate that activation occurs with a time delay. A nonlinear least- squares analysis indicates that three closed kinetic states are necessary and sufficient to model activation. Derived time constants of activation (22 degrees C) ranged from 10 ms (+10 mV) to 2 ms (+70 mV). Within the framework of Hodgkin-Huxley formalism, Ito gating can be described using an a3i formulation. PMID:8505627

  6. Effects of the Selective Stretch-Activated Channel Blocker GsMtx4 on Stretch-Induced Changes in Refractoriness in Isolated Rat Hearts and on Ventricular Premature Beats and Arrhythmias after Coronary Occlusion in Swine

    PubMed Central

    Barrabés, José A.; Inserte, Javier; Agulló, Luis; Rodríguez-Sinovas, Antonio; Alburquerque-Béjar, Juan J.; Garcia-Dorado, David

    2015-01-01

    Mechanical factors may contribute to ischemic ventricular arrhythmias. GsMtx4 peptide, a selective stretch-activated channel blocker, inhibits stretch-induced atrial arrhythmias. We aimed to assess whether GsMtx4 protects against ventricular ectopy and arrhythmias following coronary occlusion in swine. First, the effects of 170-nM GsMtx4 on the changes in the effective refractory period (ERP) induced by left ventricular (LV) dilatation were assessed in 8 isolated rat hearts. Then, 44 anesthetized, open-chest pigs subjected to 50-min left anterior descending artery occlusion and 2-h reperfusion were blindly allocated to GsMtx4 (57 μg/kg iv. bolus and 3.8 μg/kg/min infusion, calculated to attain the above concentration in plasma) or saline, starting 5-min before occlusion and continuing until after reflow. In rat hearts, LV distension induced progressive reductions in ERP (35±2, 32±2, and 29±2 ms at 0, 20, and 40 mmHg of LV end-diastolic pressure, respectively, P<0.001) that were prevented by GsMTx4 (33±2, 33±2, and 32±2 ms, respectively, P=0.002 for the interaction with LV end-diastolic pressure). Pigs receiving GsMtx4 had similar number of ventricular premature beats during the ischemic period as control pigs (110±28 vs. 103±21, respectively, P=0.842). There were not significant differences among treated and untreated animals in the incidence of ventricular fibrillation (13.6 vs. 22.7%, respectively, P=0.696) or tachycardia (36.4 vs. 50.0%, P=0.361) or in the number of ventricular tachycardia episodes during the occlusion period (1.8±0.7 vs. 5.5±2.6, P=0.323). Thus, GsMtx4 administered under these conditions does not suppress ventricular ectopy following coronary occlusion in swine. Whether it might protect against malignant arrhythmias should be tested in studies powered for these outcomes. PMID:25938516

  7. Effects of the Selective Stretch-Activated Channel Blocker GsMtx4 on Stretch-Induced Changes in Refractoriness in Isolated Rat Hearts and on Ventricular Premature Beats and Arrhythmias after Coronary Occlusion in Swine.

    PubMed

    Barrabés, José A; Inserte, Javier; Agulló, Luis; Rodríguez-Sinovas, Antonio; Alburquerque-Béjar, Juan J; Garcia-Dorado, David

    2015-01-01

    Mechanical factors may contribute to ischemic ventricular arrhythmias. GsMtx4 peptide, a selective stretch-activated channel blocker, inhibits stretch-induced atrial arrhythmias. We aimed to assess whether GsMtx4 protects against ventricular ectopy and arrhythmias following coronary occlusion in swine. First, the effects of 170-nM GsMtx4 on the changes in the effective refractory period (ERP) induced by left ventricular (LV) dilatation were assessed in 8 isolated rat hearts. Then, 44 anesthetized, open-chest pigs subjected to 50-min left anterior descending artery occlusion and 2-h reperfusion were blindly allocated to GsMtx4 (57 μg/kg iv. bolus and 3.8 μg/kg/min infusion, calculated to attain the above concentration in plasma) or saline, starting 5-min before occlusion and continuing until after reflow. In rat hearts, LV distension induced progressive reductions in ERP (35±2, 32±2, and 29±2 ms at 0, 20, and 40 mmHg of LV end-diastolic pressure, respectively, P<0.001) that were prevented by GsMTx4 (33±2, 33±2, and 32±2 ms, respectively, P=0.002 for the interaction with LV end-diastolic pressure). Pigs receiving GsMtx4 had similar number of ventricular premature beats during the ischemic period as control pigs (110±28 vs. 103±21, respectively, P=0.842). There were not significant differences among treated and untreated animals in the incidence of ventricular fibrillation (13.6 vs. 22.7%, respectively, P=0.696) or tachycardia (36.4 vs. 50.0%, P=0.361) or in the number of ventricular tachycardia episodes during the occlusion period (1.8±0.7 vs. 5.5±2.6, P=0.323). Thus, GsMtx4 administered under these conditions does not suppress ventricular ectopy following coronary occlusion in swine. Whether it might protect against malignant arrhythmias should be tested in studies powered for these outcomes.

  8. Deformations of non-compact complex curves and envelopes of meromorphy of spheres

    SciTech Connect

    Ivashkovich, S M; Shevchishin, V V

    1998-10-31

    The paper discusses the properties of the envelopes of meromorphy of neighbourhoods of symplectically immersed two-spheres in complex Kahler surfaces. The method used to study the envelopes of meromorphy is based on Gromov's theory of pseudoholomorphic curves. The exposition includes a construction of a complete family of holomorphic deformations of a non-compact complex curve in a complex manifold parametrized by a finite-codimensional analytic subset of a Banach ball. The existence of this family is used to prove a generalization of Levi's continuity principle, which is applied to describe envelopes of meromorphy.

  9. Abstract generalized vector quasi-equilibrium problems in noncompact Hadamard manifolds.

    PubMed

    Lu, Haishu; Wang, Zhihua

    2017-01-01

    This paper deals with the abstract generalized vector quasi-equilibrium problem in noncompact Hadamard manifolds. We prove the existence of solutions to the abstract generalized vector quasi-equilibrium problem under suitable conditions and provide applications to an abstract vector quasi-equilibrium problem, a generalized scalar equilibrium problem, a scalar equilibrium problem, and a perturbed saddle point problem. Finally, as an application of the existence of solutions to the generalized scalar equilibrium problem, we obtain a weakly mixed variational inequality and two mixed variational inequalities. The results presented in this paper unify and generalize many known results in the literature.

  10. Localization of supersymmetric field theories on non-compact hyperbolic three-manifolds

    NASA Astrophysics Data System (ADS)

    Assel, Benjamin; Martelli, Dario; Murthy, Sameer; Yokoyama, Daisuke

    2017-03-01

    We study supersymmetric gauge theories with an R-symmetry, defined on non-compact, hyperbolic, Riemannian three-manifolds, focusing on the case of a supersymmetry-preserving quotient of Euclidean AdS3. We compute the exact partition function in these theories, using the method of localization, thus reducing the problem to the computation of one-loop determinants around a supersymmetric locus. We evaluate the one-loop determinants employing three different techniques: an index theorem, the method of pairing of eigenvalues, and the heat kernel method. Along the way, we discuss aspects of supersymmetry in manifolds with a conformal boundary, including supersymmetric actions and boundary conditions.

  11. QED{sub 3} on a space-time lattice: Compact versus noncompact formulation

    SciTech Connect

    Fiore, R.; Giudice, P.; Giuliano, D.; Marmottini, D.; Papa, A.; Sodano, P.

    2005-11-01

    We study quantum electrodynamics in a (2+1)-dimensional space-time with two flavors of dynamical fermions by numerical simulations on the lattice. We discretize the theory using both the compact and the noncompact formulations and analyze the behavior of the chiral condensate and of the monopole density in the finite lattice regime as well as in the continuum limit. By comparing the results obtained with the two approaches, we draw some conclusions about the possible equivalence of the two lattice formulations in the continuum limit.

  12. Ethnic differences in ventricular hypertrabeculation on cardiac MRI in elite football players.

    PubMed

    Luijkx, T; Cramer, M J; Zaidi, A; Rienks, R; Senden, P J; Sharma, S; van Hellemondt, F J; Buckens, C F; Mali, W P; Velthuis, B K

    2012-10-01

    Left ventricular (LV) trabeculation may be more pronounced in ethnic African than in Caucasian (European) athletes, leading to possible incorrect diagnosis of left ventricular non-compaction cardiomyopathy (LVNC). This study investigates ethnic differences in LV hypertrabeculation amongst elite athletes with cardiac magnetic resonance (CMR) and electrocardiography (ECG). 38 elite male football (soccer) players (mean age 23.0, range 19-34 years, 28/38 European, 10/38 African) underwent CMR and ECG. Hypertrabeculation was assessed using the ratio of non-compacted to compacted myocardium (NC/C ratio) on long-axis and short-axis segments. ECGs were systematically rated. No significant differences were seen in ventricular volumes, wall mass or E/A ratio, whereas biventricular ejection fraction (EF) was significantly lower in African athletes (European/African athletes LVEF 55/50 %, p = 0.02; RVEF 51/48 %, p = 0.05). Average NC/C ratio was greater in African athletes but only significantly at mid-ventricular level (European/African athletes: apical 0.91/1.00, p = 0.65; mid-ventricular 0.89/1.45, p < 0.05; basal 0.40/0.46, p = 0.67). ECG readings demonstrated no significant group differences, and no correlation between ECG anomalies and hypertrabeculation. A greater degree of LV hypertrabeculation is seen in healthy African athletes, combined with biventricular EF reduction at rest. Recognition of this phenomenon is necessary to avoid misdiagnosis of LVNC.

  13. Evaluation of the operatorial Q-system for non-compact super spin chains

    NASA Astrophysics Data System (ADS)

    Frassek, Rouven; Marboe, Christian; Meidinger, David

    2017-09-01

    We present an approach to evaluate the full operatorial Q-system of all u(p,q\\Big|r+s) -invariant spin chains with representations of Jordan-Schwinger type. In particular, this includes the super spin chain of planar N=4 super Yang-Mills theory at one loop in the presence of a diagonal twist. Our method is based on the oscillator construction of Q-operators. The Q-operators are built as traces over Lax operators which are degenerate solutions of the Yang-Baxter equation. For non-compact representations these Lax operators may contain multiple infinite sums that conceal the form of the resulting functions. We determine these infinite sums and calculate the matrix elements of the lowest level Q-operators. Transforming the Lax operators corresponding to the Q-operators into a representation involving only finite sums allows us to take the supertrace and to obtain the explicit form of the Q-operators in terms of finite matrices for a given magnon sector. Imposing the functional relations, we then bootstrap the other Q-operators from those of the lowest level. We exemplify this approach for non-compact spin - s spin chains and apply it to N=4 at the one-loop level using the BMN vacuum as an example.

  14. A computational method of evaluating noncompact sound based on vortex sound theory.

    PubMed

    Takaishi, T; Miyazawa, M; Kato, C

    2007-03-01

    A numerical investigation is made of the production of sound by turbulence interacting with a noncompact body. The problem is formulated in the frequency domain by extending the theory of vortex sound proposed by Howe. The anomalous "numerical" generation of sound by the sudden termination of Lighthill's stress tensor at the outer boundary of a finite computational domain is avoided by identification of "scattered" sound sources that generate sound principally by interaction with the solid surface. It is argued that the boundary element method is the most efficient means of computing the aeroacoustic Green's function for the problem, because it requires a minimum of CPU time, is not prone to numerical errors such as dispersion and dissipation during propagation, and the radiation condition is easily applied at the outer boundary. The method is applied to the problem of sound generation by high Reynolds number flow past a circular cylinder. The "scattered" sources are shown to be confined to the vicinity of the cylinder surface. At low frequencies the radiation has a dipole-like directivity in agreement with the compact approximation. However, the directivity is quite different at high frequencies, where our noncompact method predicts a more complicated "leaf-like" radiation pattern.

  15. Classification of Invariant Differential Operators for Non-Compact Lie Algebras via Parabolic Relations

    NASA Astrophysics Data System (ADS)

    Dobrev, V. K.

    2014-05-01

    In the present paper we review the progress of the project of classification and construction of invariant differential operators for non-compact semisimple Lie groups. Our starting points is the class of algebras, which we called earlier 'conformal Lie algebras' (CLA), which have very similar properties to the conformal algebras of Minkowski space-time, though our aim is to go beyond this class in a natural way. For this we introduced recently the new notion of parabolic relation between two non-compact semisimple Lie algebras G and G' that have the same complexification and possess maximal parabolic subalgebras with the same complexification. Thus, we consider the exceptional algebra E7(7) which is parabolically related to the CLA E7(-25). Other interesting examples are the orthogonal algebras so(p, q) all of which are parabolically related to the conformal algebra so(n, 2) with p + q = n + 2, the parabolic subalgebras including the Lorentz subalgebra so(n - 1,1) and its analogs so(p - 1, q - 1). Further we consider the algebras sl(2n, Bbb R) and for n = 2k the algebras su* (4k) which are parabolically related to the CLA su(n,n). Further we consider the algebras sp(r,r) which are parabolically related to the CLA sp(2r, Bbb R). We consider also E6(6) and E6(2) which are parabolically related to the hermitian symmetric case E6(-14),

  16. Ellagic acid and gingerol, activators of the sarco-endoplasmic reticulum Ca²⁺-ATPase, ameliorate diabetes mellitus-induced diastolic dysfunction in isolated murine ventricular myocardia.

    PubMed

    Namekata, Iyuki; Hamaguchi, Shogo; Wakasugi, Yumi; Ohhara, Minato; Hirota, Yoshitaka; Tanaka, Hikaru

    2013-04-15

    The effects of sarco-endoplasmic reticulum Ca(2+)-ATPase (SERCA) activators, ellagic acid and gingerol, on the contraction and Ca(2+) transient were examined in isolated myocardia from streptozotocin-induced diabetic mice and compared with control mice. The time required for relaxation of the right ventricular free wall was significantly longer in streptozotocin-treated mice. The basal Ca(2+) concentration of isolated ventricular myocytes from streptozotocin-treated mice was significantly higher than those from control mice. The Ca(2+) transient decay rate was significantly lower in myocytes from streptozotocin-treated mice. Cyclopiazonic acid, a SERCA inhibitor, decreased the rate of relaxation and the rate of Ca(2+) transient decay; these effects were larger in control mice. Both ellagic acid and gingerol accelerated the rate of relaxation and the rate of Ca(2+) transient decay; these effects were larger in the streptozotocin-treated mice. The acceleration of relaxation by ellagic acid and gingerol was completely inhibited by cyclopiazonic acid. These results suggest that the diabetes mellitus-induced myocardial diastolic dysfunction is partly caused by reduction of SERCA function and can be ameliorated by SERCA activators.

  17. Isolation of cardiac myosin light-chain isotypes by chromatofocusing. Comparison of human cardiac atrial light-chain 1 and foetal ventricular light-chain 1.

    PubMed

    Vincent, N D; Cummins, P

    1985-04-01

    Cardiac myosin light chain isotypes have been resolved using chromatofocusing, a new preparative column chromatographic technique. The method relies on production of narrow-range, shallow and stable pH gradients using ion-exchange resins and buffers with even buffering capacity over the required pH range. Light chains were resolved in order of decreasing isoelectric point in the pH range 5.2-4.5. Gradients of delta pH = 0.004-0.006/ml elution volume were achieved which were capable of resolving light chains with isoelectric point differences of only 0.03. Analytical isoelectric focusing of light chains in polyacrylamide gels could be used to predict the results of preparative chromatofocusing for method development. Chromatofocusing was capable of resolving human and bovine cardiac light chain 1 and 2 subunits, atrial (ALC) and ventricular (VLC) light chain isotypes and homologous VLC-2 and VLC-2* light chains. The technique was used to purify and resolve the human foetal ventricular light chain 1 (FLC-1) from adult ventricular light chain 1 (VLC-1) present in foetal ventricles and the atrial light chain 1 (ALC-1) in adult atria. Comparative peptide mapping studies and amino acid analyses were carried out on FLC-1 and ALC-1. No differences were detected between FLC-1 and ALC-1 using three different proteases and amino acid compositions were similar with the exception of glycine content. The studies indicate that FLC-1 and ALC-1 are homologous, and possibly identical, light chains. Comparison of human FLC-1/ALC-1 with VLC-1 suggested marked structural and chemical differences in these light chain isotypes, in particular in the contents of methionine, proline, lysine and alanine residues. Differences in the contents of these residues were also apparent in the corresponding bovine atrial and ventricular light chains [Wikman-Coffelt, J. & Srivastava, S. (1979) FEBS Lett. 106, 207-212]. The latter three residues are known to be rich in the N-termini of cardiac and

  18. Dual-site right ventricular and left ventricular pacing in a patient with left ventricular systolic dysfunction and atrial fibrillation using a standard CRT-D device.

    PubMed

    Chase, David; Kumar, Vipin; Hooda, Amit

    2013-07-01

    In patients undergoing cardiac resynchronization therapy with defibrillator (CRT-D) implantation for left ventricular systolic dysfunction (LVSD) accompanied by permanent atrial fibrillation (AF), generally, the unused atrial port is plugged at device implantation. We describe an alternative use for the atrial-port in this case report. A 43 year old gentleman with LVSD due to left ventricular non-compaction (LVNC) and AF of unknown duration underwent a CRT-D implantation after optimization of cardiac failure treatment. The atrial-port which would otherwise have been plugged was connected to a high right ventricular septal (RVS) pacing-lead and the shock-lead was positioned at the right ventricular apex (RVA). This approach permitted modified cardiac resynchronization in a high RVS to left ventricular (LV) and RVA pacing sequence using the high RVS and LV pacing combined with a shock vector including the RV apex. A standard CRT-D device with a minimum programmable A-V delay of 30 ms (technically RVS to LV delay in the 'DDD' pacing mode) was used. The device was programmed to a 'DDD' pacing mode (sequential multi-site ventricular pacing with some programmability). The mode switch operation was programmed 'OFF' since atrial sensing is unavailable. Device-delivered shocks did not cardiovert the patient back to sinus rhythm suggesting that the AF was permanent (no prior cardioversion attempts were made on the presumption that the chances of maintaining sinus rhythm, given the underlying cardiac condition, were low). Subsequently, the patient required radio-frequency ablation of the atrio-ventricular node for conducted AF. Symptomatic, echocardiographic and radiological improvement preceded atrio-ventricular node ablation. Amongst AF patients with permanent AF undergoing CRT-D implantation, those patients who are likely to have the CRT-D device atrial-ports plugged could benefit from having both the options of (i) a RVA shock vector as well as (ii) a high RVS

  19. [Repetitive monomorphic ventricular tachycardia].

    PubMed

    Maia, I G; Cruz Filho, F; Costa, A M; Boghossian, S H; Fagundes, M; Ribeiro, J C; Sá, R; Alves, P A

    1994-01-01

    To evaluate retrospectively clinical features of repetitive monomorphic ventricular tachycardia (RMVT). Files of 11 patients with RMVT were analyzed (9 females, mean-age 37 +/- 17 years). All patients were submitted to clinical evaluation, ECG, Holter monitoring stress test, high-resolution ECG and echocardiogram; they were treated with antiarrhythmic drugs. Patients were in NYHA class I or II, 9 asymptomatics and 2 with palpitations. The ECG was normal in all of them. Cardiac memory was observed in 3. A left bundle branch block with inferior axis deviation in the frontal plane was present during RMVT in all patients (right ventricular outflow tract focus). Holter monitoring revealed mean of 12031 +/- 8345 isolated PVC/24h; 2892 +/- 234 ventricular couplets/24h and 1367 +/- 890 VTs/24h (mainly nonsustained). In 6 patients RMVT was suppressed during maximal exercise treadmill. High-resolution ECG was negative in all group. Five patients had a normal echocardiogram while 5 showed mitral valve prolapse. One patient developed tachycardiomyopathy. The arrhythmia was controlled with 320mg of oral sotalol in 3 of 4 that used this drug and with 120mg oral propranolol in one of 6 that used this drug. Drug resistance was present in the others. The mean follow-up period was 38 +/- 16 months. The results demonstrate that RMVT is a benign form of VT with no detectable anatomic substract by the currently used methods. It is probably induced by nonreentrant mechanism and frequently drug resistance is observed. Among the antiarrhythmic drugs commonly used, sotalol showed to be the most effective.

  20. Coordinating cardiomyocyte interactions to direct ventricular chamber morphogenesis

    PubMed Central

    Han, Peidong; Bloomekatz, Joshua; Ren, Jie; Zhang, Ruilin; Grinstein, Jonathan D.; Zhao, Long; Burns, C. Geoffrey; Burns, Caroline E.; Anderson, Ryan M.; Chi, Neil C.

    2016-01-01

    Many organs are composed of complex tissue walls that are structurally organized to optimize organ function. In particular, the ventricular myocardial wall of the heart is comprised of an outer compact layer that concentrically encircles the ridge-like inner trabecular layer. Although disruption in the morphogenesis of this myocardial wall can lead to various forms of congenital heart disease (CHD)1 and non-compaction cardiomyopathies2, it remains unclear how embryonic cardiomyocytes assemble to form ventricular wall layers of appropriate spatial dimensions and myocardial mass. Here, we utilize advanced genetic and imaging tools in zebrafish to reveal an interplay between myocardial Notch and Erbb2 signaling that directs the spatial allocation of myocardial cells to their proper morphologic positions in the ventricular wall. Although previous studies have shown that endocardial Notch signaling non-cell-autonomously promotes myocardial trabeculation through Erbb2 and BMP signaling3, we discover that distinct ventricular cardiomyocyte clusters exhibit myocardial Notch activity that cell-autonomously inhibits Erbb2 signaling and prevents cardiomyocyte sprouting and trabeculation. Myocardial-specific Notch inactivation leads to ventricles of reduced size and increased wall thickness due to excessive trabeculae, whereas widespread myocardial Notch activity results in ventricles of increased size with a single-cell thick wall but no trabeculae. Notably, this myocardial Notch signaling is activated non-cell-autonomously by neighboring Erbb2-activated cardiomyocytes that sprout and form nascent trabeculae. Thus, these findings support an interactive cellular feedback process that guides the assembly of cardiomyocytes to morphologically create the ventricular myocardial wall and more broadly provides insight into the cellular dynamics of how diverse cell lineages organize to create form. PMID:27357797

  1. Cardiac involvement of primary hyperoxaluria accompanied by non-compaction cardiomyopathy and patent ductus arteriosus.

    PubMed

    Arat, Nurcan; Akyıldız, Murat; Tellioğlu, Gürkan; Tokat, Yaman

    2015-04-01

    Primary hyperoxaluria is a rare hereditary metabolic disorder resulting in accumulation of calcium oxalate in visceral organs, including the heart. We report a 19-year-old male with non- compaction cardiomyopathy combined with patent ductus arteriosus awaiting combined liver-kidney transplantation for primary hyperoxaluria. After surgical closure of the patent ductus arteriosus, the patient underwent a successful renal and subsequent liver transplantation. The presence of hypertrophic cardiomyopathy in hyperoxaluria patients has been reported before, but this is the first report of non-compaction myocardium with patent ductus arteriosus in a patient with primary hyperoxaluria. At the third month after combined liver and renal transplantation, improvement in cardiac functions were observed. Primary hyperoxaluria is a clinical entity to be taken into consideration in differential diagnosis of hypertrophied myocardium with high myocardial echocardiographic intensity. In cases of hyperoxaluria, additional congenital abnormalities may complicate the clinical picture.

  2. Invariant differential operators for non-compact Lie groups: The main su(n, n) cases

    SciTech Connect

    Dobrev, V. K.

    2013-08-15

    In the present paper we continue the project of systematic construction of invariant differential operators on the example of the non-compact algebras su(n, n). Our choice of these algebras is motivated by the fact that for n = 2 this is the conformal algebra of 4-dimensional Minkowski space-time. Furthermore for general n these algebras belong to a narrow class of algebras, which we call 'conformal Lie algebras', which have very similar properties to the conformal algebras of n{sup 2}-dimensional Minkowski space-time. We give the main multiplets of indecomposable elementary representations for n = 2, 3, 4, including the necessary data for all relevant invariant differential operators.

  3. Invariant differential operators for non-compact Lie algebras parabolically related to conformal Lie algebras

    NASA Astrophysics Data System (ADS)

    Dobrev, V. K.

    2013-02-01

    In the present paper we continue the project of systematic construction of invariant differential operators for non-compact semisimple Lie groups. Our starting points is the class of algebras, which we call 'conformal Lie algebras' (CLA), which have very similar properties to the conformal algebras of Minkowski space-time, though our aim is to go beyond this class in a natural way. For this we introduce the new notion of parabolic relation between two non-compact semisimple Lie algebras G and G ' that have the same complexification and possess maximal parabolic subalgebras with the same complexification. Thus, we consider the exceptional algebra E 7(7) which is parabolically related to the CLA E 7(-25) , the parabolic subalgebras including E 6(6) and E 6(-26). Other interesting examples are the orthogonal algebras so(p, q) all of which are parabolically related to the conformal algebra so( n, 2) with p + q = n + 2, the parabolic subalgebras including the Lorentz subalgebra so( n - 1, 1) and its analogs so( p - 1, q - 1). We consider also E6(6) and E6(2) which are parabolically related to the hermitian symmetric case E6(-14) , the parabolic subalgebras including real forms of sl(6). We also give a formula for the number of representations in the main multiplets valid for CLAs and all algebras that are parabolically related to them. In all considered cases we give the main multiplets of indecomposable elementary representations including the necessary data for all relevant invariant differential operators. In the case of so( p, q) we give also the reduced multiplets. We should stress that the multiplets are given in the most economic way in pairs of shadow fields. Furthermore we should stress that the classification of all invariant differential operators includes as special cases all possible conservation laws and conserved currents, unitary or not.

  4. Decreased glycolytic metabolism in non-compaction cardiomyopathy by 18F-fluoro-2-deoxyglucose positron emission tomography: new insights into pathophysiological mechanisms and clinical implications.

    PubMed

    Tavares de Melo, Marcelo Dantas; Giorgi, Maria Clementina Pinto; Assuncao, Antonildes Nascimento; Dantas, Roberto Nery; Araujo Filho, Jose de Arimateia; Parga Filho, Jose Rodrigues; Bierrenbach, Ana Luiza de Souza; de Lima, Camila Rocon; Soares, José; Meneguetti, José Claudio; Mady, Charles; Hajjar, Ludhmila Abrahão; Kalil Filho, Roberto; Bocchi, Edimar Alcides; Salemi, Vera Maria Cury

    2017-05-01

    The pathophysiological mechanisms of left ventricular non-compaction cardiomyopathy (LVNC) remain controversial. This study performed combined 18F-fluoro-2-deoxyglucose dynamic positron emission tomography (FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (SPECT) studies to evaluate myocardial glucose metabolism and perfusion in patients with LVNC and their clinical implications. Thirty patients (41 ± 12 years, 53% male) with LVNC, diagnosed by cardiovascular magnetic resonance (CMR) criteria, and eight age-matched healthy controls (42 ± 12 years, 50% male) were prospectively recruited to undergo FDG-PET with measurement of the myocardial glucose uptake rate (MGU) and SPECT to investigate perfusion-metabolism patterns. Patients with LVNC had lower global MGU compared with that in controls (36.9 ± 8.8 vs. 44.6 ± 5.4 μmol/min/100 g, respectively, P = 0.02). Of 17 LV segments, MGU levels were significantly reduced in 8, and also a reduction was observed when compacted segments from LVNC were compared with the segments from control subjects (P < 0.001). Perfusion defects were also found in 15 (50%) patients (45 LV segments: 64.4% match, and 35.6% mismatch perfusion-metabolism pattern). Univariate and multivariate analyses showed that beta-blocker therapy was associated with increased MGU (beta coefficient = 10.1, P = 0.008). Moreover, a gradual increase occurred in MGU across the beta-blocker dose groups (P for trend = 0.01). The reduction of MGU documented by FDG-PET in LVNC supports the hypothesis that a cellular metabolic pathway may play a role in the pathophysiology of LVNC. The beneficial effect of beta-blocker mediating myocardial metabolism in the clinical course of LVNC requires further investigation.

  5. Spatiotemporal evolution of ventricular fibrillation

    NASA Astrophysics Data System (ADS)

    Witkowski, Francis X.; Leon, L. Joshua; Penkoske, Patricia A.; Giles, Wayne R.; Spano, Mark L.; Ditto, William L.; Winfree, Arthur T.

    1998-03-01

    Sudden cardiac death is the leading cause of death in the industrialized world, with the majority of such tragedies being due to ventricular fibrillation. Ventricular fibrillation is a frenzied and irregular disturbance of the heart rhythm that quickly renders the heart incapable of sustaining life. Rotors, electrophysiological structures that emit rotating spiral waves, occur in several systems that all share with the heart the functional properties of excitability and refractoriness. These re-entrant waves, seen in numerical solutions of simplified models of cardiac tissue, may occur during ventricular tachycardias,. It has been difficult to detect such forms of re-entry in fibrillating mammalian ventricles. Here we show that, in isolated perfused dog hearts, high spatial and temporal resolution mapping of optical transmembrane potentials can easily detect transiently erupting rotors during the early phase of ventricular fibrillation. This activity is characterized by a relatively high spatiotemporal cross-correlation. During this early fibrillatory interval, frequent wavefront collisions and wavebreak generation are also dominant features. Interestingly, this spatiotemporal pattern undergoes an evolution to a less highly spatially correlated mechanism that lacks the epicardial manifestations of rotors despite continued myocardial perfusion.

  6. Total Clinical Course and Autopsy Findings of Left Ventricular Outflow Tract Obstruction Due to Sigmoid Septum: Histologically Proven Isolated Basal Septal Hypertrophy.

    PubMed

    Kawai, Keisuke; Sengoku, Hiroyuki; Ishihara, Hiroyuki; Akematsu, Tomotoshi; Nanahoshi, Masakazu; Hariki, Hirotoshi; Hasokawa, Minoru; Hirata, Ken-Ichi; Yamabe, Hiroshi

    2017-08-15

    We herein report the total course and autopsy findings of a woman who complained of chest discomfort and had plasma B-type natriuretic peptide 43 pg/mL and left ventricular outflow tract obstruction (with a resting pressure gradient of 181 mmHg) due to sigmoid septum at 73 years of age. Betaxolol and verapamil decreased her pressure gradient to 14 mmHg, but the pressure gradient (101 mmHg) again worsened. The betaxolol dose was increased and cibenzoline was added, resulting in a pressure gradient ≤21 mmHg. An autopsy was performed after death from a urinary tract infection at 80 years of age. The absence of any disarray of cardiac myocytes was confirmed.

  7. Added value of cardiac magnetic resonance in etiological diagnosis of ventricular arrhythmias.

    PubMed

    Cabanelas, Nuno; Vidigal Ferreira, Maria João; Donato, Paulo; Gaspar, António; Pinto, Joana; Caseiro-Alves, Filipe; Providência, Luís Augusto

    2013-10-01

    Cardiac magnetic resonance (CMR) imaging is increasingly important in the diagnostic work-up of a wide range of heart diseases, including those with arrhythmogenic potential. To assess the added value of CMR in etiological diagnosis of ventricular arrhythmias after an inconclusive conventional investigation. Patients undergoing CMR between 2005 and 2011 for investigation of ventricular arrhythmias were included (n=113). All had documented arrhythmias. Those with a definite diagnosis from a previous investigation and those with evidence of coronary artery disease (acute coronary syndrome, typical angina symptoms, increase in biomarkers or positive stress test) were excluded. CMR results were considered relevant when they fulfilled diagnostic criteria. Of the 113 patients, 57.5% were male and mean age was 41.7 ± 16.2 years. Regarding the initial arrhythmia, 38.1% had ventricular fibrillation/sustained ventricular tachycardia (VF/VT) and 61.9% had less complex ventricular ectopy. CMR imaging showed criteria of a specific diagnosis in 42.5% of patients, was totally normal in 36.3%, and showed non-specific alterations in the remainder. In VF/VT patients, specific criteria were found in 60.4%, and in 31.4% of those with less complex ectopy. The most frequent diagnoses were arrhythmogenic right ventricular dysplasia, ventricular non-compaction and myopericarditis. It is worth noting that, although there was no evidence of previous coronary artery disease, 6.2% of patients had a late gadolinium enhancement distribution pattern compatible with myocardial infarction. CMR gives additional and important information in the diagnostic work-up of ventricular arrhythmias after an inconclusive initial investigation. The proportion of patients with diagnostic criteria was 42.5% (60.0% in those with VF/VT), and CMR was completely normal in 36.6%. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  8. Quantum reference frames associated with noncompact groups: The case of translations and boosts and the role of mass

    NASA Astrophysics Data System (ADS)

    Smith, Alexander R. H.; Piani, Marco; Mann, Robert B.

    2016-07-01

    Quantum communication without a shared reference frame or the construction of a relational quantum theory requires the notion of a quantum reference frame. We analyze aspects of quantum reference frames associated with noncompact groups, specifically, the group of spatial translations and Galilean boosts. We begin by demonstrating how the usually employed group average, used to dispense of the notion of an external reference frame, leads to unphysical states when applied to reference frames associated with noncompact groups. However, we show that this average does lead naturally to a reduced state on the relative degrees of freedom of a system, which was previously considered by Angelo et al. [J. Phys. A: Math. Theor. 44, 145304 (2011), 10.1088/1751-8113/44/14/145304]. We then study in detail the informational properties of this reduced state for systems of two and three particles in Gaussian states.

  9. Inverse scattering theory: Inverse scattering series method for one dimensional non-compact support potential

    SciTech Connect

    Yao, Jie; Lesage, Anne-Cécile; Hussain, Fazle; Bodmann, Bernhard G.; Kouri, Donald J.

    2014-12-15

    The reversion of the Born-Neumann series of the Lippmann-Schwinger equation is one of the standard ways to solve the inverse acoustic scattering problem. One limitation of the current inversion methods based on the reversion of the Born-Neumann series is that the velocity potential should have compact support. However, this assumption cannot be satisfied in certain cases, especially in seismic inversion. Based on the idea of distorted wave scattering, we explore an inverse scattering method for velocity potentials without compact support. The strategy is to decompose the actual medium as a known single interface reference medium, which has the same asymptotic form as the actual medium and a perturbative scattering potential with compact support. After introducing the method to calculate the Green’s function for the known reference potential, the inverse scattering series and Volterra inverse scattering series are derived for the perturbative potential. Analytical and numerical examples demonstrate the feasibility and effectiveness of this method. Besides, to ensure stability of the numerical computation, the Lanczos averaging method is employed as a filter to reduce the Gibbs oscillations for the truncated discrete inverse Fourier transform of each order. Our method provides a rigorous mathematical framework for inverse acoustic scattering with a non-compact support velocity potential.

  10. [Left ventricular diastolic dysfunction. Implications for anesthesia and critical care].

    PubMed

    Meierhenrich, R; Schütz, W; Gauss, A

    2008-11-01

    Over the last two decades there has been a growing recognition that cardiac function is not solely determined by systolic but also essentially by diastolic function. Left ventricular diastolic dysfunction is characterized by an impairment of ventricular filling caused either by abnormal relaxation, an active energy consuming process or decreased compliance, which is determined by passive tissue properties of the ventricle. Doppler echocardiography, including tissue Doppler imaging, has emerged as the preferred clinical tool for the assessment of left ventricular diastolic function. Recently the importance of left ventricular diastolic function is increasingly being recognized also during the perioperative period. Newer studies have shown that after cardiopulmonary bypass there is a significant decrease in left ventricular compliance. Experimental studies have demonstrated that sepsis is associated with a decrease in both active relaxation and ventricular compliance. Initial studies are also focusing on therapeutic options for patients with isolated diastolic dysfunction.

  11. Right ventricular failure after left ventricular assist device insertion: preoperative risk factors.

    PubMed

    Santambrogio, Luisa; Bianchi, Tiziana; Fuardo, Marinella; Gazzoli, Fabrizio; Veronesi, Roberto; Braschi, Antonio; Maurelli, Marco

    2006-08-01

    Right ventricular failure after left ventricular assist device placement is the major concern on weaning from cardiopulmonary bypass and it is one of the most serious complications in the postoperative period. This complication has a poor prognosis and is generally unpredictable. The identification of pre-operative risk factor for this serious complication is incomplete yet. In order to determine pre-operative risk for severe right ventricular failure after left ventricular assist device support we analyzed preoperative hemodynamics, laboratory data and characteristics of 48 patients who received Novacor (World Heart Corp., Ottawa, ON, Canada). We compared the data from the patients who developed right ventricular failure and the patients who did not. Right ventricular failure occurred in 16% of the patients. There was no significant difference between the groups in demographic characteristics. We identified as preoperative risk factors the pre-operative low mean pulmonary artery and the impairment of hepatic and renal function on laboratory data. Our results confirm in part the findings of the few previous studies. This information may be useful for the patient selection for isolated left ventricular assist device implantation, but other studies are necessary before establishing criteria for patient selection for univentricular support universally accepted.

  12. Deficiency in the mouse mitochondrial adenine nucleotide translocator isoform 2 gene is associated with cardiac noncompaction.

    PubMed

    Kokoszka, Jason E; Waymire, Katrina G; Flierl, Adrian; Sweeney, Katelyn M; Angelin, Alessia; MacGregor, Grant R; Wallace, Douglas C

    2016-08-01

    The mouse fetal and adult hearts express two adenine nucleotide translocator (ANT) isoform genes. The predominant isoform is the heart-muscle-brain ANT-isoform gene 1 (Ant1) while the other is the systemic Ant2 gene. Genetic inactivation of the Ant1 gene does not impair fetal development but results in hypertrophic cardiomyopathy in postnatal mice. Using a knockin X-linked Ant2 allele in which exons 3 and 4 are flanked by loxP sites combined in males with a protamine 1 promoter driven Cre recombinase we created females heterozygous for a null Ant2 allele. Crossing the heterozygous females with the Ant2(fl), PrmCre(+) males resulted in male and female ANT2-null embryos. These fetuses proved to be embryonic lethal by day E14.5 in association with cardiac developmental failure, immature cardiomyocytes having swollen mitochondria, cardiomyocyte hyperproliferation, and cardiac failure due to hypertrabeculation/noncompaction. ANTs have two main functions, mitochondrial-cytosol ATP/ADP exchange and modulation of the mitochondrial permeability transition pore (mtPTP). Previous studies imply that ANT2 biases the mtPTP toward closed while ANT1 biases the mtPTP toward open. It has been reported that immature cardiomyocytes have a constitutively opened mtPTP, the closure of which signals the maturation of cardiomyocytes. Therefore, we hypothesize that the developmental toxicity of the Ant2 null mutation may be the result of biasing the cardiomyocyte mtPTP to remain open thus impairing cardiomyocyte maturation and resulting in cardiomyocyte hyperproliferation and failure of trabecular maturation. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Local and global existence of mild solution to impulsive fractional semilinear integro-differential equation with noncompact semigroup

    NASA Astrophysics Data System (ADS)

    Gou, Haide; Li, Baolin

    2017-01-01

    In this paper, we study local and global existence of mild solution for an impulsive fractional functional integro differential equation with non-compact semi-group in Banach spaces. We establish a general framework to find the mild solutions for impulsive fractional integro-differential equations, which will provide an effective way to deal with such problems. The theorems proved in this paper improve and extend some related conclusions on this topic. Finally, two applications are given to illustrate that our results are valuable.

  14. Engineering human ventricular heart muscles based on a highly efficient system for purification of human pluripotent stem cell-derived ventricular cardiomyocytes.

    PubMed

    Li, Bin; Yang, Hui; Wang, Xiaochen; Zhan, Yongkun; Sheng, Wei; Cai, Huanhuan; Xin, Haoyang; Liang, Qianqian; Zhou, Ping; Lu, Chao; Qian, Ruizhe; Chen, Sifeng; Yang, Pengyuan; Zhang, Jianyi; Shou, Weinian; Huang, Guoying; Liang, Ping; Sun, Ning

    2017-09-29

    Most infarctions occur in the left anterior descending coronary artery and cause myocardium damage of the left ventricle. Although current pluripotent stem cells (PSCs) and directed cardiac differentiation techniques are able to generate fetal-like human cardiomyocytes, isolation of pure ventricular cardiomyocytes has been challenging. For repairing ventricular damage, we aimed to establish a highly efficient purification system to obtain homogeneous ventricular cardiomyocytes and prepare engineered human ventricular heart muscles in a dish. The purification system used TALEN-mediated genomic editing techniques to insert the neomycin or EGFP selection marker directly after the myosin light chain 2 (MYL2) locus in human pluripotent stem cells. Purified early ventricular cardiomyocytes were estimated by immunofluorescence, fluorescence-activated cell sorting, quantitative PCR, microelectrode array, and patch clamp. In subsequent experiments, the mixture of mature MYL2-positive ventricular cardiomyocytes and mesenchymal cells were cocultured with decellularized natural heart matrix. Histological and electrophysiology analyses of the formed tissues were performed 2 weeks later. Human ventricular cardiomyocytes were efficiently isolated based on the purification system using G418 or flow cytometry selection. When combined with the decellularized natural heart matrix as the scaffold, functional human ventricular heart muscles were prepared in a dish. These engineered human ventricular muscles can be great tools for regenerative therapy of human ventricular damage as well as drug screening and ventricular-specific disease modeling in the future.

  15. Vagal modulation of cardiac ventricular arrhythmia.

    PubMed

    Ng, G André

    2014-02-01

    What is the topic of this review? This article addresses the relationship between vagus nerve activity and malignant ventricular arrhythmias. It focuses on the clinical association of an impaired vagal tone in cardiac disease states with high mortality from sudden cardiac death and the potential underlying mechanisms. What advances does it highlight? The article summarizes the mounting evidence that vagal innervation in the cardiac ventricle plays a key direct role in the prevention of the initiation of ventricular fibrillation. Data are presented on the role that nitric oxide plays in mediating the effects of vagal protection against ventricular fibrillation, supporting the notion that a separate non-muscarinic, nitrergic population of vagal neurons is responsible for this protection. Sudden cardiac death remains a significant unresolved clinical problem, with many of the deaths being due to malignant ventricular arrhythmias. Markers of abnormal autonomic function have been shown to be strong prognostic predictors, highlighting the important relationship between reduced vagal tone and malignant ventricular arrhythmias, such as ventricular fibrillation, in cardiac patients. Exploring the mechanisms underlying the autonomic modulation of ventricular fibrillation, my group has shown that vagus nerve stimulation protects against ventricular fibrillation in the innervated isolated heart preparation. We have provided direct evidence that nitric oxide is released in the ventricle with cervical vagus nerve stimulation and NO mediates the antifibrillatory actions of vagus nerve stimulation in the ventricle. Classical physiology teaches that vagal postganglionic nerves modulate the heart via acetylcholine acting at muscarinic receptors and, dogmatically, that there is little vagal effect in the ventricle, as innervation was believed to be sparse. Mounting evidence from many species now supports the presence of a rich vagal innervation in the ventricle. Data from my group

  16. [Treatment of ventricular tachycardia].

    PubMed

    Iturralde Torres, P

    2001-01-01

    Evaluation and management of postinfarct ventricular tachycardia has changed dramatically in the past two decades. The introduction of the implantable cardioverter defibrillator has played a major role in this change, alternating both, the purpose of the patients evaluation and treatment options. Episodes of sustained ventricular tachycardia can occur in a variety of clinical settings; the most common of which is the patient who has suffered a myocardial infarction. In this paper, I explore the causes and effects of some of these changes and review current strategies, specially the radiofrequency catheter ablation, for the management of the patient with postinfarct ventricular tachycardia.

  17. 14-3-3ε Plays a Role in Cardiac Ventricular Compaction by Regulating the Cardiomyocyte Cell Cycle

    PubMed Central

    Kosaka, Yasuhiro; Cieslik, Katarzyna A.; Li, Ling; Lezin, George; Maguire, Colin T.; Saijoh, Yukio; Toyo-oka, Kazuhito; Gambello, Michael J.; Vatta, Matteo; Wynshaw-Boris, Anthony; Baldini, Antonio; Yost, H. Joseph

    2012-01-01

    Trabecular myocardium accounts for the majority of the ventricles during early cardiogenesis, but compact myocardium is the primary component at later developmental stages. Elucidation of the genes regulating compact myocardium development is essential to increase our understanding of left ventricular noncompaction (LVNC), a cardiomyopathy characterized by increased ratios of trabecular to compact myocardium. 14-3-3ε is an adapter protein expressed in the lateral plate mesoderm, but its in vivo cardiac functions remain to be defined. Here we show that 14-3-3ε is expressed in the developing mouse heart as well as in cardiomyocytes. 14-3-3ε deletion did not appear to induce compensation by other 14-3-3 isoforms but led to ventricular noncompaction, with features similar to LVNC, resulting from a selective reduction in compact myocardium thickness. Abnormal compaction derived from a 50% decrease in cardiac proliferation as a result of a reduced number of cardiomyocytes in G2/M and the accumulation of cardiomyocytes in the G0/G1 phase of the cell cycle. These defects originated from downregulation of cyclin E1 and upregulation of p27Kip1, possibly through both transcriptional and posttranslational mechanisms. Our work shows that 14-3-3ε regulates cardiogenesis and growth of the compact ventricular myocardium by modulating the cardiomyocyte cell cycle via both cyclin E1 and p27Kip1. These data are consistent with the long-held view that human LVNC may result from compaction arrest, and they implicate 14-3-3ε as a new candidate gene in congenital human cardiomyopathies. PMID:23071090

  18. Ventricular Septal Defect (VSD)

    MedlinePlus

    ... specially sized mesh device to close the hole. Hybrid procedure. A hybrid procedure uses surgical and catheter-based techniques. Access ... clinicalkey.com. Accessed Sept. 15, 2014. Konetti NR. Hybrid muscular ventricular defect closure: Surgeon or physician. Indian ...

  19. Left Ventricular Hypertrophy

    MedlinePlus

    ... than are white people with similar blood pressure measurements. Sex. Women with hypertension are at higher risk ... hypertrophy than are men with similar blood pressure measurements. Left ventricular hypertrophy changes the structure and working ...

  20. [Bradykinin and ventricular function].

    PubMed

    Trochu, J N

    2002-03-01

    Kinins are vasodilator peptides implicated in many physiological and physiopathological processes such as blood pressure regulation and that of the coronary circulation and inflammatory reactions. Kinins play an essential role in ventricular function as they counteract the effects of angiotensin II during myocardial ischaemia, ventricular remodelling and severe cardiac failure, emphasising the value of treatment favouring local endogenic production of bradykinin such as ACE inhibitors, neutral endopeptidase inhibitors and antagonists of AT1 receptors of angiotensin II.

  1. [Arrhythmogenic right ventricular dysplasia].

    PubMed

    Maia, I G; Sá, R; Bassan, R; Alves, P; Ribeiros, J C; Loyola, L H; Cruz Filho, F E; Valverde, A; Belém, L

    1991-08-01

    To evaluate the clinical findings and complementary investigation to support the diagnosis of arrhythmogenic right ventricular dysplasia. Six males with a mean age of 40 years old with episodes of sustained ventricular tachycardia with left bundle branch block pattern. All patients were submitted to a clinical investigation, EKG X rays and echocardiograms. In five patients an electrophysiologic study was performed. All patients were treated with anti-arrhythmic drugs. Palpitation was the most common complaint. T-wave inversion in leads V1-V3 was present in 4 patients. An epsilon wave was noted in 2 patients. The chest X ray was abnormal in only 1 patient. All patients had an abnormal echocardiogram, with consisted in the dilatation of the outflow tract of the RV and hypocontractility. In 2 patients aneurysm of the basal RV free wall below tricuspid valve were detected. Ventricular post-excitation waves were present in 4 patients. After a mean follow-up of 37 months, 5 patients were asymptomatic with anti-arrhythmic drugs and one in therapeutic adjustment. In patients with ventricular tachycardia with left bundle branch block pattern, the diagnosis of arrhythmogenic right ventricular dysplasia was substantiated by echocardiographic data and electrocardiographic findings such a T-wave inversion during sinus rhythm and ventricular post-excitation waves. The results obtained with anti-arrhythmic drugs in our study group, suggest that drug therapy should be the first and best approach to treat patients with this type of pathology.

  2. Xanthine oxidase contributes to preconditioning's preservation of left ventricular developed pressure in isolated rat heart: developed pressure may not be an appropriate end-point for studies of preconditioning.

    PubMed

    Gelpi, Ricardo J; Morales, Celina; Cohen, Michael V; Downey, James M

    2002-01-01

    Studies of preconditioning frequently use the isolated rat heart model in which recovery of post-ischemic function is the end-point. However, function following an episode of ischemia/reperfusion represents a composite of both stunning, which is related to free radical production and is not attenuated by preconditioning, and tissue salvage, the primary effect of preconditioning. Brief ischemia/reperfusion is also known to diminish adenosine release during subsequent ischemia by a mechanism independent of preconditioning's anti-infarct effect. Reduced purine release would diminish generation of free radicals by xanthine oxidase in rat heart and thus produce less stunning. In this paradigm preserved post-ischemic function in rat heart might look similar to salvage by preconditioning, but its mechanism would be quite different and not be relevant to the xanthine oxidase-deficient human heart. This hypothesis was tested in isolated rat hearts. Control or ischemically preconditioned hearts were subjected to 30 min of global ischemia and 60 min of reperfusion, either in the presence or absence of 25 micromol/l allopurinol, an inhibitor of xanthine oxidase. In non-preconditioned hearts allopurinol increased left ventricular developed pressure after 60 min of reperfusion from 26 +/- 5 mmHg in control hearts to 47 +/- 7 mmHg, whereas developed pressure in preconditioned hearts following reperfusion was 59 +/- 5 mmHg and was unaffected by allopurinol. Developed pressure in non-preconditioned hearts treated with allopurinol was midway between that for untreated control and preconditioned hearts suggesting that at least 50% of the recovery of developed pressure in preconditioned hearts may be related to free radical-induced stunning. In xanthine oxidase-deficient rabbit hearts, return of function was not different between non-preconditioned and preconditioned hearts. Therefore, post-ischemic developed pressure in the rat is significantly affected by purine-dependent stunning

  3. Right ventricular sarcoidosis: is it time for updated diagnostic criteria?

    PubMed

    Vakil, Kairav; Minami, Elina; Fishbein, Daniel P

    2014-04-01

    A 55-year-old woman with a history of complete heart block, atrial flutter, and progressive right ventricular failure was referred to our tertiary care center to be evaluated for cardiac transplantation. The patient's clinical course included worsening right ventricular dysfunction for 3 years before the current evaluation. Our clinical findings raised concerns about arrhythmogenic right ventricular cardiomyopathy. Noninvasive imaging, including a positron emission tomographic scan, did not reveal obvious myocardial pathologic conditions. Given the end-stage nature of the patient's right ventricular failure and her dependence on inotropic agents, she underwent urgent listing and subsequent heart transplantation. Pathologic examination of the explanted heart revealed isolated right ventricular sarcoidosis with replacement fibrosis. Biopsy samples of the cardiac allograft 6 months after transplantation showed no recurrence of sarcoidosis. This atypical presentation of isolated cardiac sarcoidosis posed a considerable diagnostic challenge. In addition to discussing the patient's case, we review the relevant medical literature and discuss the need for updated differential diagnostic criteria for end-stage right ventricular failure that mimics arrhythmogenic right ventricular cardiomyopathy.

  4. Ivabradine Reduces Digitalis-induced Ventricular Arrhythmias.

    PubMed

    Frommeyer, Gerrit; Weller, Jan; Ellermann, Christian; Bögeholz, Nils; Leitz, Patrick; Dechering, Dirk G; Kochhäuser, Simon; Wasmer, Kristina; Eckardt, Lars

    2017-06-19

    The I(f) channel inhibitor ivabradine is recommended for treatment of heart failure but also affects potassium currents and thereby prolongs ventricular repolarization. The aim of this study was to examine the electrophysiological effects of ivabradine on digitalis-induced ventricular arrhythmias. Thirteen rabbit hearts were isolated and Langendorff-perfused. After obtaining baseline data, the digitalis glycoside ouabain was infused (0.2 μM). Monophasic action potentials and ECG showed a significant abbreviation of QT interval (-34 ms, p < 0.05) and action potential duration (APD90 ; -27 ms, p < 0.05). The shortening of ventricular repolarization was accompanied by a reduction in effective refractory period (ERP; -27 ms, p < 0.05). Thereafter, hearts were additionally treated with ivabradine (5 μM). Of note, this did not exert significant effects on QT interval (-4 ms, p = ns) or APD90 (-15 ms, p = ns) but resulted in an increase in ERP (+17 ms, p < 0.05). This led to a significant increase in post-repolarization refractoriness (PRR, +32 ms, p < 0.01) as compared with sole ouabain treatment. Under baseline conditions, ventricular fibrillation (VF) was inducible by a standardized pacing protocol including programmed stimulation and burst stimulation in four of 13 hearts (31%; 15 episodes). After application of 0.2 μM ouabain, eight of 13 hearts were inducible (62%, 49 episodes). Additional infusion of 5 μM ivabradine led to a significant suppression of VF. Only four episodes could be induced in two of 13 hearts (15%). In this study, ivabradine reduced digitalis-induced ventricular arrhythmias. Ivabradine did not affect ventricular repolarization in the presence of digitalis treatment but demonstrated potent anti-arrhythmic properties based on an increase in both ERP and PRR. The study further characterizes the beneficial electrophysiological profile of ivabradine. © 2017 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  5. Vulnerability to ventricular fibrillation

    NASA Astrophysics Data System (ADS)

    Janse, Michiel J.

    1998-03-01

    One of the factors that favors the development of ventricular fibrillation is an increase in the dispersion of refractoriness. Experiments will be described in which an increase in dispersion in the recovery of excitability was determined during brief episodes of enhanced sympathetic nerve activity, known to increase the risk of fibrillation. Whereas in the normal heart ventricular fibrillation can be induced by a strong electrical shock, a premature stimulus of moderate intensity only induces fibrillation in the presence of regional ischemia, which greatly increases the dispersion of refractoriness. One factor that is of importance for the transition of reentrant ventricular tachycardia to ventricular fibrillation during acute regional ischemia is the subendocardial Purkinje system. After selective destruction of the Purkinje network by lugol, reentrant tachycardias still develop in the ischemic region, but they do not degenerate into fibrillation. Finally, attempts were made to determine the minimal mass of thin ventricular myocardium required to sustain fibrillation induced by burst pacing. This was done by freezing of subendocardial and midmural layers. The rim of surviving epicardial muscle had to be larger than 20 g. Extracellular electrograms during fibrillation in both the intact and the "frozen" left ventricle were indistinguishable, but activation patterns were markedly different. In the intact ventricle epicardial activation was compatible with multiple wavelet reentry, in the "frozen" heart a single, or at most two wandering reentrant waves were seen.

  6. Intellectual disability and non-compaction cardiomyopathy with a de novo NONO mutation identified by exome sequencing.

    PubMed

    Reinstein, Eyal; Tzur, Shay; Cohen, Rony; Bormans, Concetta; Behar, Doron M

    2016-11-01

    Pathogenic variants in the NONO gene have been most recently implicated in X-linked intellectual disability syndrome. This observation has been supported by studies of NONO-deficient mice showing that NONO has an important role in regulating inhibitory synaptic activity. Thus far, the phenotypic spectrum of affected patients remains limited. We applied whole exome sequencing to members of a family in which the proband was presented with a complex phenotype consisting of developmental delay, dysmorphism, and non-compaction cardiomyopathy. Exome analysis identified a novel de novo splice-site variant c.1171+1G>T in exon 11 of NONO gene that is suspected to abolish the donor splicing site. Thus, we propose that the phenotypic spectrum of NONO-related disorder is much broader than described and that pathogenic variants in NONO cause a recognizable phenotype.

  7. Glycolytic oscillations in isolated rabbit ventricular myocytes.

    PubMed

    Yang, Jun-Hai; Yang, Ling; Qu, Zhilin; Weiss, James N

    2008-12-26

    Previous studies have shown that glycolysis can oscillate periodically, driven by feedback loops in regulation of key glycolytic enzymes by free ADP and other metabolites. Here we show both theoretically and experimentally in cardiac myocytes that when the capacity of oxidative phosphorylation and the creatine kinase system to buffer the cellular ATP/ADP ratio is suppressed, glycolysis can cause large scale periodic oscillations in cellular ATP levels (0.02-0.067 Hz), monitored from glibenclamide-sensitive changes in action potential duration or intracellular free Mg2+. Action potential duration oscillations originate primarily from glycolysis, since they 1) occur in the presence of cyanide or rotenone, 2) are suppressed by iodoacetate, 3) are accompanied by at most very small mitochondrial membrane potential oscillations, and 4) exhibit an anti-phase relationship to NADH fluorescence. By uncoupling energy supply-demand balance, glycolytic oscillations may promote injury and electrophysiological heterogeneity during acute metabolic stresses, such as acute myocardial ischemia in which both oxidative phosphorylation and creatine kinase activity are inhibited.

  8. Prevalence, Patterns, and Clinical Predictors of Left Ventricular Late Gadolinium Enhancement in Patients Undergoing Cardiac Magnetic Resonance Prior to Pulmonary Vein Antral Isolation for Atrial Fibrillation: A Cross-Sectional Observational Study.

    PubMed

    Nance, John W; Khurram, Irfan M; Nazarian, Saman; DeWire, Jane; Calkins, Hugh; Zimmerman, Stefan L

    2015-09-01

    Cardiac magnetic resonance (CMR) imaging is increasingly used to evaluate patients with atrial fibrillation (AF) before pulmonary vein antral isolation (PVAI). The purpose of this study was to assess the incidence and pattern of left ventricular (LV) late gadolinium enhancement (LGE) in patients undergoing CMR before PVAI and compare the clinical and demographic differences of patients with and without LV LGE. Clinical and demographic data on 62 patients (mean age 61 ± 7.9, 69% male) undergoing CMR before PVAI for AF were collected. Two observers, masked to clinical histories, independently recorded the prevalence, extent (number of myocardial segments), and pattern (subendocardial, midmyocardial, or subepicardial) of LV LGE in each patient. Clinical and demographic predictors of LV LGE were determined using logistic regression. Twenty-three patients (37%) demonstrated LV LGE affecting a mean of 3.0 ± 2.1 myocardial segments. There was no difference in LV ejection fraction between patients with and without LGE, and most (65%) patients with LGE had normal wall motion. Only age (P = 0.04) and a history of congestive heart failure (P = .03) were statistically significant independent predictors of LGE. The most common LGE pattern was midmyocardial, seen in 17 of 23 (74%) patients. Only 4 of 23 (17%) patients had LGE in an "expected" pattern based on clinical history. Of the remaining 19 patients, 4 had known congestive heart failure, 5 nonischemic cardiomyopathy, 4 known coronary artery disease, and 2 prior aortic valve replacement. Six of 23 (26%) patients had no known coronary artery, valvular, or myocardial disease. There is a high prevalence of unexpected LV scar in patients undergoing CMR before PVAI for AF, with most patients demonstrating a nonischemic pattern of LV LGE and no wall motion abnormalities (ie, subclinical disease). The high prevalence of unexpected LGE in these patients may argue for CMR as the modality of choice for imaging

  9. Ventricular Septal Defect (For Parents)

    MedlinePlus

    ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System ECG (Electrocardiogram) Anesthesia - What to Expect Tetralogy of ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System Contact Us Print Resources Send to a friend ...

  10. Ventricular Septal Defect (For Parents)

    MedlinePlus

    ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System ECG (Electrocardiogram) Anesthesia - What to Expect Tetralogy of ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System Contact Us Print Resources Send to a Friend ...

  11. Large right ventricular thrombus.

    PubMed

    Sousa, Carla; Almeida, Pedro; Gonçalves, Alexandra; Rodrigues, João; Rangel, Inês; Macedo, Filipe; Maciel, M Júlia

    2014-01-01

    Right ventricular thrombosis is a rare yet potentially fatal condition. It has been described in association with hypercoagulability states, autoimmune diseases and dilated cardiomyopathy. Echocardiography constitutes the election tool for diagnosis and characterization of these entities, allowing for the differentiation between the various types of thrombi. We present a case of a patient with alcoholic dilated cardiomyopathy admitted for congestive heart failure and lower respiratory infection. In the diagnostic approach, a routine echocardiography revealed a large mural right ventricular thrombus in association with severe biventricular dysfunction. The patient was proposed for anticoagulation strategy, which he refused.

  12. Right ventricular dysfunction affects survival after surgical left ventricular restoration.

    PubMed

    Couperus, Lotte E; Delgado, Victoria; Palmen, Meindert; van Vessem, Marieke E; Braun, Jerry; Fiocco, Marta; Tops, Laurens F; Verwey, Harriëtte F; Klautz, Robert J M; Schalij, Martin J; Beeres, Saskia L M A

    2017-04-01

    Several clinical and left ventricular parameters have been associated with prognosis after surgical left ventricular restoration in patients with ischemic heart failure. The aim of this study was to determine the prognostic value of right ventricular function. A total of 139 patients with ischemic heart failure (62 ± 10 years; 79% were male; left ventricular ejection fraction 27% ± 7%) underwent surgical left ventricular restoration. Biventricular function was assessed with echocardiography before surgery. The independent association between all-cause mortality and right ventricular fractional area change, tricuspid annular plane systolic excursion, and right ventricular longitudinal peak systolic strain was assessed. The additive effect of multiple impaired right ventricular parameters on mortality also was assessed. Baseline right ventricular fractional area change was 42% ± 9%, tricuspid annular plane systolic excursion was 18 ± 3 mm, and right ventricular longitudinal peak systolic strain was -24% ± 7%. Within 30 days after surgery, 15 patients died. Right ventricular fractional area change (hazard ratio, 0.93; 95% confidence interval, 0.88-0.98; P < .01), tricuspid annular plane systolic excursion (hazard ratio, 0.80; 95% confidence interval, 0.66-0.96; P = .02), and right ventricular longitudinal peak systolic strain (hazard ratio, 1.15; 95% confidence interval, 1.05-1.26; P < .01) were independently associated with 30-day mortality, after adjusting for left ventricular ejection fraction and aortic crossclamping time. Right ventricular function was impaired in 21%, 20%, and 27% of patients on the basis of right ventricular fractional area change, tricuspid annular plane systolic excursion, and right ventricular longitudinal peak systolic strain, respectively. Any echocardiographic parameter of right ventricular dysfunction was present in 39% of patients. The coexistence of several impaired right ventricular parameters per patient was

  13. Bidirectional ventricular tachycardia?

    PubMed

    Serra, José L; Caresani, Julian A; Bono, Julio O

    2014-01-01

    A 65-year-old woman was admitted to the hospital because of a syncopal episode with documented transient complete atrioventricular block. A DDD pacemaker was implanted. Post implantation, the patient was diagnosed with bidirectional ventricular tachycardia. Analysis of the arrhythmia and differential diagnosis is performed.

  14. Left ventricular bronchogenic cyst.

    PubMed

    Wei, Xiang; Omo, Alfred; Pan, Tiecheng; Li, Jun; Liu, Ligang; Hu, Min

    2006-04-01

    Bronchogenic cysts occurring in the left ventricle are a medical rarity. One successfully operated case is reported herein. The location of the cyst was just between the epicardium and myocardium of the inferior left ventricular wall, adjacent to the apex of the heart. Complete excision was achieved through a left anterolateral thoracotomy without extracorporeal circulation.

  15. Aorto-ventricular tunnel

    PubMed Central

    McKay, Roxane

    2007-01-01

    Aorto-ventricular tunnel is a congenital, extracardiac channel which connects the ascending aorta above the sinutubular junction to the cavity of the left, or (less commonly) right ventricle. The exact incidence is unknown, estimates ranging from 0.5% of fetal cardiac malformations to less than 0.1% of congenitally malformed hearts in clinico-pathological series. Approximately 130 cases have been reported in the literature, about twice as many cases in males as in females. Associated defects, usually involving the proximal coronary arteries, or the aortic or pulmonary valves, are present in nearly half the cases. Occasional patients present with an asymptomatic heart murmur and cardiac enlargement, but most suffer heart failure in the first year of life. The etiology of aorto-ventricular tunnel is uncertain. It appears to result from a combination of maldevelopment of the cushions which give rise to the pulmonary and aortic roots, and abnormal separation of these structures. Echocardiography is the diagnostic investigation of choice. Antenatal diagnosis by fetal echocardiography is reliable after 18 weeks gestation. Aorto-ventricular tunnel must be distinguished from other lesions which cause rapid run-off of blood from the aorta and produce cardiac failure. Optimal management of symptomatic aorto-ventricular tunnel consists of diagnosis by echocardiography, complimented with cardiac catheterization as needed to elucidate coronary arterial origins or associated defects, and prompt surgical repair. Observation of the exceedingly rare, asymptomatic patient with a small tunnel may be justified by occasional spontaneous closure. All patients require life-long follow-up for recurrence of the tunnel, aortic valve incompetence, left ventricular function, and aneurysmal enlargement of the ascending aorta. PMID:17922908

  16. Aorto-ventricular tunnel.

    PubMed

    McKay, Roxane

    2007-10-08

    Aorto-ventricular tunnel is a congenital, extracardiac channel which connects the ascending aorta above the sinutubular junction to the cavity of the left, or (less commonly) right ventricle. The exact incidence is unknown, estimates ranging from 0.5% of fetal cardiac malformations to less than 0.1% of congenitally malformed hearts in clinico-pathological series. Approximately 130 cases have been reported in the literature, about twice as many cases in males as in females. Associated defects, usually involving the proximal coronary arteries, or the aortic or pulmonary valves, are present in nearly half the cases. Occasional patients present with an asymptomatic heart murmur and cardiac enlargement, but most suffer heart failure in the first year of life. The etiology of aorto-ventricular tunnel is uncertain. It appears to result from a combination of maldevelopment of the cushions which give rise to the pulmonary and aortic roots, and abnormal separation of these structures. Echocardiography is the diagnostic investigation of choice. Antenatal diagnosis by fetal echocardiography is reliable after 18 weeks gestation. Aorto-ventricular tunnel must be distinguished from other lesions which cause rapid run-off of blood from the aorta and produce cardiac failure. Optimal management of symptomatic aorto-ventricular tunnel consists of diagnosis by echocardiography, complimented with cardiac catheterization as needed to elucidate coronary arterial origins or associated defects, and prompt surgical repair. Observation of the exceedingly rare, asymptomatic patient with a small tunnel may be justified by occasional spontaneous closure. All patients require life-long follow-up for recurrence of the tunnel, aortic valve incompetence, left ventricular function, and aneurysmal enlargement of the ascending aorta.

  17. Pure right ventricular infarction.

    PubMed

    Inoue, Katsuji; Matsuoka, Hiroshi; Kawakami, Hideo; Koyama, Yasushi; Nishimura, Kazuhisa; Ito, Taketoshi

    2002-02-01

    A 76-year-old man with chest pain was admitted to hospital where electrocardiography (ECG) showed ST-segment elevation in leads V1-4, indicative of acute anterior myocardial infarction. ST-segment elevation was also present in the right precordial leads V4R-6R. Emergency coronary angiography revealed that the left coronary artery was dominant and did not have significant stenosis. Aortography showed ostial occlusion of the right coronary artery (RCA). Left ventriculography showed normal function and right ventriculography showed a dilated right ventricle and severe hypokinesis of the right ventricular free wall. Conservative treatment was selected because the patient's symptoms soon ameliorated and his hemodynamics was stable. 99mTc-pyrophosphate and 201Tl dual single-photon emission computed tomography showed uptake of 99mTc-pyrophosphate in only the right ventricular free wall, but no uptake of 99mTc-pyrophosphate and no perfusion defect of 201Tl in the left ventricle. The peak creatine kinase (CK) and CK-MB were 1,381 IU/L and 127 IU/L, respectively. His natural course was favorable and the chest pain disappeared under medication. Two months after the onset, the ECG showed poor R progression in leads V1-4 indicating an old anterior infarction. Coronary angiography confirmed the ostial stenosis of the hypoplastic RCA. This was a case of pure right ventricular free wall infarction because of the occlusion of the ostium of the hypoplastic RCA, but not of the right ventricular branch. Because the electrocardiographic findings resemble those of an acute anterior infarction, it is important to consider pure right ventricular infarction in the differential diagnosis.

  18. [Ventricular "remodeling" after myocardial infarction].

    PubMed

    Cohen-Solal, A; Himbert, D; Guéret, P; Gourgon, R

    1991-06-01

    Cardiac failure is the principal medium-term complication of myocardial infarction. Changes in left ventricular geometry are observed after infarction, called ventricular remodeling, which, though compensatory initially, cause ventricular failure in the long-term. Experimental and clinical studies suggest that early treatment by coronary recanalisation, trinitrin and angiotensin converting enzyme inhibitors may prevent or limit the expansion and left ventricular dilatation after infarction, so improving ventricular function, and, at least in the animal, reduce mortality. Large scale trials with converting enzyme inhibitors are currently under way to determine the effects of this new therapeutic option. It would seem possible at present, independently of any reduction in the size of the infarction, to reduce or delay left ventricular dysfunction by interfering with the natural process of dilatation and ventricular modeling after infarction.

  19. Ventricular tachycardia in ischemic heart disease substrates

    PubMed Central

    Ajijola, Olujimi A.; Tung, Roderick; Shivkumar, Kalyanam

    2014-01-01

    Advances in the treatment of myocardial infarction (MI) have improved survival after ischemic cardiac injury. Post-infarct structural and functional remodeling results in electrophysiologic substrates at risk for monomorphic ventricular tachycardia (MMVT). Characterization of this substrate using a variety of clinical and investigative tools has improved our understanding of MMVT circuits, and has accelerated the development of device and catheter-based therapies aimed at identification and elimination of this arrhythmia. This review will discuss the central role of the ischemic heart disease substrate in the development MMVT. Electrophysiologic characterization of the post-infarct myocardium using bipolar electrogram amplitudes to delineate scar border zones will be reviewed. Functional electrogram determinants of reentrant circuits such as isolated late potentials will be discussed. Strategies for catheter ablation of reentrant ventricular tachycardia, including structural and functional targets will also be examined, as will the role of the epicardial mapping and ablation in the management of recurrent MMVT. PMID:24568826

  20. [Relationship between mitral valve prolapse and arrhythmogenic right ventricular disease].

    PubMed

    Costa, A M; Maia, I G; Cruz Filho, F; Fagundes, M L; Sá, R; Alves, P

    1996-12-01

    To evaluate some features of ventricular arrhythmias in patients with mitral valve prolapse. We studied 25 patients (female: 19; mean age: 37 +/- 13 years) with ventricular arrhythmias, mitral valve prolapse and normal ventricular function. All patients underwent a 24h Holter and high resolution ECG (HRECG). The Qtc intervals were measured in lead II (normal < 0.44 s). In order to define the possible origin of the ventricular focus, the morphology of the ectopic beats were analysed in leads I, II, aVF, V1 using the following criteria: 1) LBBB morphology with left axis deviation in the frontal plane (FP): origin at the inflow tract of the right ventricle (RV); 2) LBBB morphology with right axis deviation in the FP: origin at the outflow tract of the RV; 3) RBBB morphology with left axis deviation in the FP: origin at the posterior region of the left ventricle (LV). RBBB morphology with right axis deviation in the FP: origin at the anterior region of the LV. Twenty three (92%) patients showed > 720 isolated ventricular ectopic beats/24 h. Paired ventricular response was detected in 18 (72%) patients and non-sustained VT in 15 (60%). HRECG was positive in six (24%) patients and Qtc interval was prolonged in 13 (52%). RV was the site of origin of the ventricular ectopic beats in 85% of the patients (outflow: 85%; inflow: 15%). Only five (20%) patients had arrhythmias from the LV. There was a high incidence of ventricular arrhythmias with a low incidence of positive HRECG tests, suggesting that the mechanisms of the arrhythmias do not correlate with slow intramyocardial conduction. It was noted a strong association between mitral valve prolapse, arrhythmogenic right ventricular disease and Qtc prolongation. It is possible that in some of this patients the finding could represent a global myocardial disease.

  1. Left ventricular mural thrombus

    SciTech Connect

    Nixon, J.V.

    1983-08-01

    The identification of mural thrombus in patients with left ventricular aneurysm and mural thrombus probably warrants consideration of long-term anticoagulation. In patients with acute, large, anterior or anteroapical, transmural myocardial infarctions, serial noninvasive examinations are warranted to define a group of patients at high risk for the development of left ventricular aneurysm and/or mural thrombus. Anticoagulants should be considered in patients in whom mural thrombi develop as a complication of their infarction. Patients with congestive cardiomyopathy should be considered for long-term anticoagulation. These recommendations are all tempered by the realization that the use of anticoagulant therapy is not without its own risks. The decision to anticoagulate must be balanced against each individual patient's suitability for such therapy and the individual likelihood of the development of side effects.

  2. Idiopathic fascicular ventricular tachycardia.

    PubMed

    Francis, Johnson; Venugopal, K; Khadar, S A; Sudhayakumar, N; Gupta, Anoop K

    2004-07-01

    Idiopathic fascicular ventricular tachycardia is an important cardiac arrhythmia with specific electrocardiographic features and therapeutic options. It is characterized by relatively narrow QRS complex and right bundle branch block pattern. The QRS axis depends on which fascicle is involved in the re-entry. Left axis deviation is noted with left posterior fascicular tachycardia and right axis deviation with left anterior fascicular tachycardia. A left septal fascicular tachycardia with normal axis has also been described. Fascicular tachycardia is usually seen in individuals without structural heart disease. Response to verapamil is an important feature of fascicular tachycardia. Rare instances of termination with intravenous adenosine have also been noted. A presystolic or diastolic potential preceding the QRS, presumed to originate from the Purkinje fibers can be recorded during sinus rhythm and ventricular tachycardia in many patients with fascicular tachycardia. This potential (P potential) has been used as a guide to catheter ablation. Prompt recognition of fascicular tachycardia especially in the emergency department is very important. It is one of the eminently ablatable ventricular tachycardias. Primary ablation has been reported to have a higher success, lesser procedure time and fluoroscopy time.

  3. Cisapride and ventricular arrhythmia

    PubMed Central

    Hennessy, Sean; Leonard, Charles E; Newcomb, Craig; Kimmel, Stephen E; Bilker, Warren B

    2008-01-01

    AIMS We aimed to examine the association between cisapride and ventricular arrhythmia, and examine the relationship to dose and CYP3A4 inhibitors. METHODS A nested case–control study was conducted in Medicaid beneficiaries exposed to cisapride, metoclopramide or a proton pump inhibitor (PPI) from 1999 to 2000. Cases were hospitalized with a principal International Classification of Diseases-9 code indicating sudden cardiac death or ventricular arrhythmia. Controls had at least as much event-free person time following the study prescription as its matched case. RESULTS A total of 145 cases and 7250 controls were identified. The unadjusted rate ratio for cisapride vs. PPIs was 1.49 (95% confidence interval 0.96, 2.25). The adjusted odds ratio (OR) for cisapride vs. PPIs was 2.10 (1.34, 3.28). Excluding persons in managed care, the adjusted OR for cisapride was 2.92 (1.55, 5.49). In the initial prescription period, the adjusted OR for cisapride vs. PPIs was 7.85 (1.95, 31.60). Non-arrhythmogenic CYP3A4 inhibitors were not associated with an increased risk in users of cisapride or PPI inhibitors. The OR for potentially arrhythmogenic CYP3A4 inhibitors was 3.79 (1.76, 8.15) in cisapride users and 3.47 (2.06, 5.83) in PPI users. CONCLUSIONS Cisapride was associated with a doubling to tripling of the risk of hospitalization for ventricular arrhythmia, and a nearly eightfold risk in the initial prescription period. Although use of potentially arrhythmogenic CYP3A4 inhibitors was associated with an increased risk, this appears to be due to a direct effect of the drugs themselves rather than an interaction with cisapride. WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Case reports have linked cisapride to ventricular arrhythmia and sudden cardiac death. However, two prior epidemiological studies have failed to show an association between cisapride and serious arrhythmia. WHAT THIS STUDY ADDS Overall, cisapride was associated with a doubling to tripling of the risk of

  4. Ventricular hypertrophy in cardiomyopathy.

    PubMed

    Oakley, C

    1971-01-01

    Semantic difficulties arise when hypertrophic obstructive cardiomyopathy is seen without obstruction and with congestive failure, and also when congestive cardiomyopathy is seen with gross hypertrophy but without heart failure. Retention of a small left ventricular cavity and a normal ejection fraction characterizes hypertrophic cardiomyopathy at all stages of the disorder. Congestive cardiomyopathy is recognized by the presence of a dilated left ventricular cavity and reduced ejection fraction regardless of the amount of hypertrophy and the presence or not of heart failure. Longevity in congestive cardiomyopathy seems to be promoted when hypertrophy is great relative to the amount of pump failure as measured by increase in cavity size. Conversely, death in hypertrophic cardiomyopathy is most likely when hypertrophy is greatest at a time when outflow tract obstruction has been replaced by inflow restriction caused by diminishing ventricular distensibility. Hypertrophy is thus beneficial and compensatory in congestive cardiomyopathy, whereas it may be the primary disorder and eventual cause of death in hypertrophic cardiomyopathy. Reasons are given for believing that hypertension may have been the original cause of left ventricular dilatation in some case of congestive cardiomyopathy in which loss of stroke output thenceforward is followed by normotension. Development of severe hypertension in these patients after recovery from a prolonged period of left ventricular failure with normotension lends weight to this hypothesis. No fault has been found in the large or small coronary arteries in either hypertrophic cardiomyopathy or congestive cardiomyopathy when they have been examined in life by selective coronary angiography, or by histological methods in biopsy or post-mortem material. Coronary blood supply may be a limiting factor in the compensatory hypertrophy of congestive cardiomyopathy, and the ability to hypertrophy may explain the better prognosis of some

  5. Ablation of idiopathic ventricular tachycardia.

    PubMed

    Schreiber, Doreen; Kottkamp, Hans

    2010-09-01

    Idiopathic ventricular arrhythmias occur in patients without structural heart disease. They can arise from a variety of specific areas within both ventricles and in the supravalvular regions of the great arteries. Two main groups need to be differentiated: arrhythmias from the outflow tract (OT) region and idiopathic left ventricular, so-called fascicular, tachycardias (ILVTs). OT tachycardia typically originates in the right ventricular OT, but may also occur in the left ventricular OT, particularly in the sinuses of Valsalva or the anterior epicardium or the great cardiac vein. Activation mapping or pace mapping for the OT regions and mapping of diastolic potentials in ILVTs are the mapping techniques that are typically used. The ablation of idiopathic ventricular arrhythmias is highly successful, associated with only rare complications. Newly recognized entities of idiopathic ventricular tachycardias are those originating in the papillary muscles and in the atrioventricular annular regions.

  6. Imaging for the Diagnosis of an Unusual Case of Left Ventricular Aneurysm

    SciTech Connect

    Russo, G. Sarais, C.; Corbetti, F.; Ramondo, A.; Daliento, L.

    2005-04-15

    An isolated ventricular diverticulum in an adult patient investigated for chest pain is reported. An exhaustive diagnosis was obtained by different means and complementary imaging techniques such as echocardiography, cardiovascular magnetic resonance imaging and cineangiography.

  7. Electrocardiogram in corrected transposition of the great vessels of the bulbo-ventricular inversion type.

    PubMed

    Fernández, F; Laurichesse, J; Scebat, L; Lenègre, J

    1970-03-01

    Twenty cases of corrected transposition of the great vessels of the bulbo-ventricular inversion type, either lone or combined with other intracardiac anomalies, were analysed. Rhythm and/or atrio-ventricular conduction disturbances were common to all groups of cases. QRS pattern changes were found to be related both to ventricular inversion and to ventricular hypertrophy. Isolated corrected transposition and corrected transposition with systemic ventriculo-atrial regurgitation give rise to tracings suggestive of systemic ventricular hypertrophy.Corrected transposition of the great vessels with pulmonary stenosis or pulmonary artery hypertension is usually accompanied by the electrocardiographic signs of a venous-ventricular hypertrophy, with a characteristic inversion of the normal praecordial pattern. The conventional criteria of ventricular hypertrophy may be applied in corrected transposition of the great vessels but are less reliable than in cases without ventricular inversion. The so-called electrocardiographic pattern of ;ventricular inversion' in this anomaly is related not only to the inverted position of the ventricles but to a greater extent to the predominant, anatomically left, venous-ventricular hypertrophy which re-establishes the normal weight ratio between the anatomically right and anatomically left ventricles.

  8. Irx4 Marks a Multipotent, Ventricular-Specific Progenitor Cell.

    PubMed

    Nelson, Daryl O; Lalit, Pratik A; Biermann, Mitch; Markandeya, Yogananda S; Capes, Deborah L; Addesso, Luke; Patel, Gina; Han, Tianxiao; John, Manorama C; Powers, Patricia A; Downs, Karen M; Kamp, Timothy J; Lyons, Gary E

    2016-12-01

    While much progress has been made in the resolution of the cellular hierarchy underlying cardiogenesis, our understanding of chamber-specific myocardium differentiation remains incomplete. To better understand ventricular myocardium differentiation, we targeted the ventricle-specific gene, Irx4, in mouse embryonic stem cells to generate a reporter cell line. Using an antibiotic-selection approach, we purified Irx4(+) cells in vitro from differentiating embryoid bodies. The isolated Irx4(+) cells proved to be highly proliferative and presented Cxcr4, Pdgfr-alpha, Flk1, and Flt1 on the cell surface. Single Irx4(+) ventricular progenitor cells (VPCs) exhibited cardiovascular potency, generating endothelial cells, smooth muscle cells, and ventricular myocytes in vitro. The ventricular specificity of the Irx4(+) population was further demonstrated in vivo as VPCs injected into the cardiac crescent subsequently produced Mlc2v(+) myocytes that exclusively contributed to the nascent ventricle at E9.5. These findings support the existence of a newly identified ventricular myocardial progenitor. This is the first report of a multipotent cardiac progenitor that contributes progeny specific to the ventricular myocardium. Stem Cells 2016;34:2875-2888. © 2016 AlphaMed Press.

  9. [Electrovectocardiographic manifestations of left ventricular and biventricular growth].

    PubMed

    de Micheli, A; Medrano, G A

    1988-01-01

    The basic criteria for the electrical diagnosis of left ventricular and biventricular enlargements are discussed on the basis of the myocardial depolarization and repolarization sequence. Left ventricular dilatation secondary to isolated diastolic overloading increases the manifestation of the main vectors resulting from the activation of this ventricle. These changes reflect the proximity of the left ventricular walls to the exploring electrodes. The above mentioned vectors appear as tall R waves and wide ventricular curves with counterclockwise rotation on the three planes. If the diastolic overload is a isolated phenomenon, T waves are positive and asymmetric on the left leads while the T loop, of secondary type, is concordant in its orientation with the R loop. This fact is due to a prolonged duration of the repolarization phase of the left ventricle. Global left ventricular hypertrophy produced by a sustained systolic overloading increases the magnitude and manifestation of all the vectors resulting from the depolarization of this ventricle (I, II l, III l) owing to the prolonged duration of the corresponding activation fronts. When LBBB is also present, the first septal vector is not evident. In extreme degrees of the systolic overload, the T wave is inverted and shows morphologic secondary characteristics in left leads, and the T loop opposes the R loop on frontal and horizontal planes. The directional changes of the repolarization fronts of free left ventricular walls can satisfactorily explain these features. Left ventricular hypertrophy of a segmentary type, such as that observed in idiopathic myocardiopathy, generally increases the magnitude and manifestation of septal vector I and II left. When both ventricles are hypertrophied, the electromotive forces originating in the more severely affected heart chamber predominate in electrical records.

  10. Ventricular fibrillation and defibrillation

    PubMed Central

    Jones, P; Lodé, N

    2007-01-01

    Cardiac arrest in children is not often due to a disturbance in rhythm that is amenable to electrical defibrillation, contrary to the situation in adults. When a shockable rhythm is present, defibrillation using an external electric shock applied at an early stage after pre‐oxygenation and chest compressions is of proven efficacy. Success at conversion of ventricular fibrillation is dependent on the delay before delivering the shock and defibrillation efficiency, which is itself a function of thoracic impedance, energy dose and waveform. PMID:17895341

  11. Giant left ventricular pseudoaneurysm.

    PubMed

    Prakash, Sumi; Garg, Nadish; Xie, Gong-Yuan; Dellsperger, Kevin C

    2010-01-01

    Left ventricular (LV) pseudoaneurysm (PS) is an uncommon, often fatal complication associated with myocardial infarction, cardiothoracic surgery, trauma, and, rarely, infective endocarditis. A 28-year-old man with prior history of bioprosthetic mitral valve replacement presented with congestive heart failure and bacteremia with Abiotrophia granulitica. Transesophageal echocardiogram showed bioprosthesis dysfunction, large vegetations, mitral regurgitation, and probable PS. Cardiac and chest CT confirmed a PS communicating with the left ventricle Patient had pulseless electrical activity and died. Autopsy showed a giant PS with layered thrombus and pseudo-endothelialized cavity. Our case highlights the importance of multimodality imaging as an important tool in management of PS.

  12. Cerebral ventricular volume during hyponatraemia.

    PubMed Central

    Decaux, G; Szyper, M; Grivegnée, A

    1983-01-01

    In order to determine if the neurologic manifestations in chronic hyponatraemia result partly from brain oedema, we measured the cerebral ventricular volume before and after correction of hyponatraemia in eight patients with central nervous system manifestations. Only the three patients with seizures showed a clear change in the ventricular size and probably had brain oedema. PMID:6101182

  13. Right ventricular metastasis of leiomyosarcoma.

    PubMed

    Dencker, Magnus; Valind, Sven; Stagmo, Martin

    2009-05-05

    Metastatic presentation of leiomyosarcoma in the heart is very rare. We present transthoracic echocardiography and combined PET/CT images of a case with a large right ventricular metastasis of leiomyosarcoma. The patient was placed on cytostatic drugs for palliative purposes, but passed away one month later because of an untreatable ventricular tackycardia.

  14. [Fascicular ventricular tachycardia].

    PubMed

    Chiarandà, G; Di Guardo, G; Gulizia, M; Lazzaro, A; Regolo, T

    2001-11-01

    Fascicular tachycardia is an uncommon idiopathic ventricular tachycardia, originating from the left ventricle; it usually occurs in young male patients, with a high prevalence in south-east Asiatic people. Electrocardiographic aspects of this unique ventricular tachycardia (right bundle branch block morphology and left or right-axis deviation, with a moderate QRS widening) and verapamil sensitivity make it often difficult the differential diagnosis with other forms of supraventricular tachycardia. Reentry is believed to be the operative mechanism of fascicular tachycardia, with the reentrant circuit located in the Purkinje network, in the region of the left posterior or anterior fascicle. The slow conduction zone participating in the reentry circuit, made up of partially depolarized Purkinje fibers, seems to be located in a relatively wide area, from the basal to the apical left interventricular septum. Intravenous verapamil is elective in acute treatment; however oral verapamil shows poor efficacy in preventing tachycardia relapses. Ablative approach is very effective; success is achieved in approximately 90% of patients, with rare complications. Recently diastolic potentials during fascicular tachycardia have been reported and these findings have given rise to new electrophysiological hypotheses and new indications about the successful ablation site.

  15. Mid-term echocardiographic follow up of left ventricular function with permanent right ventricular pacing in pediatric patients with and without structural heart disease

    PubMed Central

    Shalganov, Tchavdar Nikolov; Paprika, Dora; Vatasescu, Radu; Kardos, Attila; Mihalcz, Attila; Kornyei, Laszlo; Szatmari, Andras; Szili-Torok, Tamas

    2007-01-01

    Background Chronic right ventricular apical pacing may have detrimental effect on left ventricular function and may promote to heart failure in adult patients with left ventricular dysfunction. Methods A group of 99 pediatric patients with previously implanted pacemaker was studied retrospectively. Forty-three patients (21 males) had isolated congenital complete or advanced atrioventricular block. The remaining 56 patients (34 males) had pacing indication in the presence of structural heart disease. Thirty-two of them (21 males) had isolated structural heart disease and the remaining 24 (13 males) had complex congenital heart disease. Patients were followed up for an average of 53 ± 41.4 months with 12-lead electrocardiogram and transthoracic echocardiography. Left ventricular shortening fraction was used as a marker of ventricular function. QRS duration was assessed using leads V5 or II on standard 12-lead electrocardiogram. Results Left ventricular shortening fraction did not change significantly after pacemaker implantation compared to preimplant values overall and in subgroups. In patients with complex congenital heart malformations shortening fraction decreased significantly during the follow up period. (0.45 ± 0.07 vs 0.35 ± 0.06, p = 0.015). The correlation between the change in left ventricular shortening fraction and the mean increase of paced QRS duration was not significant. Six patients developed dilated cardiomyopathy, which was diagnosed 2 months to 9 years after pacemaker implantation. Conclusion Chronic right ventricular pacing in pediatric patients with or without structural heart disease does not necessarily result in decline of left ventricular function. In patients with complex congenital heart malformations left ventricular shortening fraction shows significant decrease. PMID:17352821

  16. Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey.

    PubMed

    van Geldorp, Irene E; Delhaas, Tammo; Gebauer, Roman A; Frias, Patrick; Tomaske, Maren; Friedberg, Mark K; Tisma-Dupanovic, Svjetlana; Elders, Jan; Früh, Andreas; Gabbarini, Fulvio; Kubus, Petr; Illikova, Viera; Tsao, Sabrina; Blank, Andreas Christian; Hiippala, Anita; Sluysmans, Thierry; Karpawich, Peter; Clur, Sally-Ann; Ganame, Xavier; Collins, Kathryn K; Dann, Gisela; Thambo, Jean-Benoît; Trigo, Conceição; Nagel, Bert; Papagiannis, John; Rackowitz, Annette; Marek, Jan; Nürnberg, Jan-Hendrik; Vanagt, Ward Y; Prinzen, Frits W; Janousek, Jan

    2011-12-01

    Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated. Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18 years were retrospectively collected from patients undergoing chronic ventricular pacing (>1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics. From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n = 147), RV endocardium (RVendo, n = 113) or LV epicardium (LVepi, n = 37). LVFS was significantly affected by pacing site (p = 0.001), and not by maternal autoantibody status (p = 0.266). LVFS in LVepi (39 ± 5%) was significantly higher than in RVendo (33 ± 7%, p < 0.001) and RVepi (35 ± 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS < 28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS ≥ 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was ≥ 50% in 17/18 (94%) LVepi-paced patients. In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing.

  17. Nonischemic Left Ventricular Scar as a Substrate of Life-Threatening Ventricular Arrhythmias and Sudden Cardiac Death in Competitive Athletes

    PubMed Central

    Zorzi, Alessandro; Perazzolo Marra, Martina; Rigato, Ilaria; De Lazzari, Manuel; Susana, Angela; Niero, Alice; Pilichou, Kalliopi; Migliore, Federico; Rizzo, Stefania; Giorgi, Benedetta; De Conti, Giorgio; Sarto, Patrizio; Serratosa, Luis; Patrizi, Giampiero; De Maria, Elia; Pelliccia, Antonio; Basso, Cristina; Schiavon, Maurizio; Bauce, Barbara; Iliceto, Sabino; Thiene, Gaetano

    2016-01-01

    Background— The clinical profile and arrhythmic outcome of competitive athletes with isolated nonischemic left ventricular (LV) scar as evidenced by contrast-enhanced cardiac magnetic resonance remain to be elucidated. Methods and Results— We compared 35 athletes (80% men, age: 14–48 years) with ventricular arrhythmias and isolated LV subepicardial/midmyocardial late gadolinium enhancement (LGE) on contrast-enhanced cardiac magnetic resonance (group A) with 38 athletes with ventricular arrhythmias and no LGE (group B) and 40 healthy control athletes (group C). A stria LGE pattern with subepicardial/midmyocardial distribution, mostly involving the lateral LV wall, was found in 27 (77%) of group A versus 0 controls (group C; P<0.001), whereas a spotty pattern of LGE localized at the junction of the right ventricle to the septum was respectively observed in 11 (31%) versus 10 (25%; P=0.52). All athletes with stria pattern showed ventricular arrhythmias with a predominant right bundle branch block morphology, 13 of 27 (48%) showed ECG repolarization abnormalities, and 5 of 27 (19%) showed echocardiographic hypokinesis of the lateral LV wall. The majority of athletes with no or spotty LGE pattern had ventricular arrhythmias with a predominant left bundle branch block morphology and no ECG or echocardiographic abnormalities. During a follow-up of 38±25 months, 6 of 27 (22%) athletes with stria pattern experienced malignant arrhythmic events such as appropriate implantable cardiac defibrillator shock (n=4), sustained ventricular tachycardia (n=1), or sudden death (n=1), compared with none of athletes with no or LGE spotty pattern and controls. Conclusions— Isolated nonischemic LV LGE with a stria pattern may be associated with life-threatening arrhythmias and sudden death in the athlete. Because of its subepicardial/midmyocardial location, LV scar is often not detected by echocardiography. PMID:27390211

  18. Left Ventricular Performance and Coronary Flow after Coronary Embolization with Plastic Microspheres

    PubMed Central

    Monroe, R. G.; LaFarge, C. G.; Gamble, W. J.; Kumar, A. E.; Manasek, F. J.

    1971-01-01

    Coronary flow, left ventricular circumference, and left ventricular pressure were observed in the isovolumically contracting, isolated canine heart supported with arterial blood from a donor. Systolic pressure, heart rate, and coronary perfusion pressure were held constant while the coronary bed was progressively embolized with either large (average 865 μ) or small (average 10 μ) polystyrene microspheres. During embolization with large microspheres, coronary flow diminished progressively. After sufficient embolization, decreased ventricular performance was indicated by a rise in end-diastolic pressure. During embolization with small microspheres, coronary flow initially increased, which suggests the effective release of a vasodilator substance. Return of coronary flow to control levels occurred only after the end-diastolic pressure rose, on the average, to above 30 mm Hg. After embolization with both sizes of microspheres, ventricular diastolic pressure-volume relationships showed decreased ventricular compliance. This was attributed, in part, to edema of the ventricular wall and, in part, to focal shortening of the sarcomeres where the circulation was compromised. Embolization with both sizes of microspheres ultimately caused a decrease in ventricular performance, although when the systolic pressure was increased the usual relationship between peak developed wall stress, and end-diastolic pressure showed less of a descending limb than that found in the nonembolized, isolated heart. It is felt that the data summarized above have bearing on ventricular performance and coronary flow in clinical situations where hearts are perfused through pump oxygenator systems and are thereby subject to embolization from aggregated clumps of platelets and fibrin. Images PMID:4999636

  19. Congenital Left Ventricular Diverticulum Complicated by Ventricular Fibrillation.

    PubMed

    Yamasaki, Manabu; Kawamatsu, Naoto; Yoshino, Kunihiko; Abe, Kohei; Misumi, Hiroyasu

    2017-09-01

    Congenital left ventricular diverticulum (CLVD) is a rare congenital anomaly and may be associated with fatal adverse events. A previously healthy 20-year-old man collapsed as a result of sudden ventricular fibrillation (VF). Despite intractable VF, he had return of spontaneous circulation with cardiopulmonary resuscitation and subsequent introduction of venoarterial extracorporeal membrane oxygenation (ECMO). After ECMO was discontinued, cardiac magnetic resonance imaging revealed CLVD at the posterolateral wall of the left ventricle. Given the risk of recurrent VF and left ventricular rupture, he underwent surgical repair for CLVD and implantation of a subcutaneous implantable cardioverter defibrillator. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Symbolic dynamics of ventricular tachycardia and ventricular fibrillation

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Chen, Jie

    2010-05-01

    In this paper, the symbolic dynamics analysis was used to analyze the complexity of normal heartbeat signal (NSR), Ventricular tachycardia (VT) and ventricular fibrillation (VF) signals. By calculating the information entropy value of symbolic sequences, the complexities were quantified. Based on different information entropy values, NSR, VT and VF signals were distinguished with satisfactory results. The study showed that a sudden drop of symbolic sequence’s entropy value indicated that the patients most likely entered the episode of ventricular tachycardia and this was a crucial episode for the clinical treatment of patients. It had important clinical significance for the automatic diagnosis.

  1. Epicardial ventricular tachycardia.

    PubMed

    Garan, Hasan

    2013-12-01

    In ventricular tachycardia (VT) arising in the myocardial tissue, the site of origin may be the endocardium, mid-myocardium or epicardium. The incidence of epicardial origin varies with the underlying heart disease, and is probably not more than 20% in ischemic heart disease and higher in non-ischemic cardiomyopathies. Percutaneous subxiphoid access to the pericardial space has enabled a non-surgical approach to catheter mapping and ablation of epicardial VT. Several algorithms are available for electrocardiographic recognition of epicardial origin. Idiopathic epicardial VTs are rare but may be curable by catheter ablation. The electrophysiologic principles guiding the mapping and ablation of epicardial VTs are similar to those used for endocardial VTs, but the biophysics of energy delivery may be different. Complications of the epicardial approach are also different from those of endocardial ablation, and specific precautions have to be taken to protect the coronary arteries and phrenic nerves and to avoid pericardial tamponade.

  2. [Late potentials and ventricular arrhythmia].

    PubMed

    Adamec, R; Zimmermann, M

    1986-04-01

    When electrodes are placed at the surface of the thorax, high-amplification electrocardiography (HA-ECG) combined with signal summation as a function of time provides a non-invasive method for detecting electric potentials occurring after the QRS complex of the clinical electrocardiogram. These potentials are called late, and can probably be likened to the "divided" or "fragmented" potentials recorded directly on the heart or in its ventricles near zones of ischemia, infarction or aneurysm. The prevalence of late potentials of ventricular activation (LPVA) and their association with the occurrence of ventricular arrhythmias seems well established, notably in the presence of ventricular aneurysm and anamnesis of severe ventricular arrhythmia. Some studies have shown that detection of LPVAs is of value in identifying heart patients at risk of ventricular arrhythmia or sudden death. Heart disease aside, the presence of LPVAs has been demonstrated in arrhythmogenic right ventricular dysplasia and reported in Fallot's tetralogy after complete correction. A standardization of recordings and a more precise definition of LPVAs are necessary before HA-ECG can become a routine clinical method. Further, the possibility of "beat by beat" recordings with "spatial" summation will allow detection of LPVAs which vary with time and in nature and hence provide a better understanding of the genesis of ventricular arrhythmias.

  3. Ventricular remodeling in global ischemia.

    PubMed

    Anversa, P; Zhang, X; Li, P; Olivetti, G; Cheng, W; Reiss, K; Sonnenblick, E H; Kajstura, J

    1995-06-01

    To determine the effects of chronic constriction of the left coronary artery on the function and structure of the heart, coronary artery narrowing was surgically induced in rats and ventricular pump performance, extent and distribution of myocardial damage, and the hypertrophic and hyperplastic response of myocytes were examined. Alterations in cardiac hemodynamics were found in all rats, but the characteristics of the physiological properties of the heart allowed a separation of the animals into two groups which exhibited left ventricular dysfunction and failure, respectively. Left ventricular hypertrophy occurred in both groups and was characterized by ventricular dilatation and wall thinning which were more severe in the failing animals. Multiple foci of myocardial damage across the wall were seen in all animals but tissue injury was more prominent in the endomyocardium and in failing rats. The anatomical and hemodynamic changes resulted in a significant increase in diastolic wall stress which paralleled the depression in ventricular performance. Myocyte cell loss and myocyte cellular hypertrophy were more severe with ventricular failure than with dysfunction. Finally, diastolic overload appeared to be coupled with activation of the DNA synthetic machinery of myocytes and nuclear mitotic division. In conclusion, a fixed lesion of the left coronary artery leads to abnormalities in cardiac dynamics with marked increases in diastolic wall stress and extensive ventricular remodeling in spite of compensatory myocyte cellular hypertrophy and hyperplasia in the remaining viable tissue.

  4. [Repetitive monomorphic ventricular tachycardia (Gallavardin type): clinical and electrophysiological characteristics in 20 patients].

    PubMed

    Hoffmann, E; Reithmann, C; Neuser, H; Nimmermann, P; Remp, T; Steinbeck, G

    1998-05-01

    Repetitive monomorphic ventricular tachycardia (RMVT) is defined by the presence of numerous monomorphic isolated, premature ventricular complexes, couplets, and runs of unsustained ventricular tachycardia having the same morphology in patients without structural heart disease. Patients with RMVT mostly demonstrate the typical left bundle branch block morphology with normal or rightward axis during tachycardia. At our institution, 20 patients with RMVT have been systematically studied: a syncope had occurred in 35% of our patients, in three cases a syncope was the first manifestation of the RMVT. Of our RMVT patients, 25% developed sustained episodes (> 3 min) of ventricular tachycardia as documented by Holter ECG. The salvos of ventricular tachycardia are generally short in RMVT. This behavior and the typical exercise dependence differentiates RMVT from paroxysmal sustained idiopathic ventricular tachycardia. Exercise testing is mandatory for correct diagnosis of RMVT. In our institution, 85-90% of RMVT patients demonstrated runs of ventricular tachycardia or sustained ventricular tachycardia while on a treadmill (exercise test) or during isoproterenol infusion. RMVT was inducible by programmed electrical right ventricular stimulation in only 13% of our patients. Therefore, in patients with suspected RMVT programmed electrophysiological stimulation is only useful to differentiate a ventricular tachycardia from a supraventricular tachycardia with bundle brunch block or in patients with unexplained syncope. The prognosis is considered generally good; in our patients no life threatening ventricular tachyarrhythmias were observed during a follow-up of up to 4 years. Verapamil and beta-adrenoceptor antagonists generally offer symptomatic improvement. In some cases treatment with a class III antiarrhythmic agent is necessary. While drug-refractory paroxysmal sustained idiopathic ventricular tachycardia can be abladed with both immediate and long-term success, catheter

  5. Arrhythmogenic right ventricular cardiomyopathy in a weimaraner

    PubMed Central

    Eason, Bryan D.; Leach, Stacey B.; Kuroki, Keiichi

    2015-01-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) was diagnosed postmortem in a weimaraner dog. Syncope, ventricular arrhythmias, and sudden death in this patient combined with the histopathological fatty tissue infiltration affecting the right ventricular myocardium are consistent with previous reports of ARVC in non-boxer dogs. Arrhythmogenic right ventricular cardiomyopathy has not been previously reported in weimaraners. PMID:26483577

  6. Right ventricular centripetal plication: an aggressive right ventricular exclusion technique.

    PubMed

    Sugiura, Junya; Murayama, Hiroomi; Okada, Noritaka

    2017-01-01

    In patients with a functional single ventricle such as neonatal Ebstein's anomaly or pulmonary atresia with intact ventricular septum, the right ventricle can compress the left ventricle and decrease its performance due to the volume or pressure overload of the right ventricle. We have performed right ventricular centripetal plication from the inside to exclude the right ventricle and to minimize the adverse effect on the left ventricle and the results have been satisfactory.

  7. MR imaging appearance of fetal cerebral ventricular morphology.

    PubMed

    Levine, Deborah; Trop, Isabelle; Mehta, Tejas S; Barnes, Patrick D

    2002-06-01

    To elucidate further the magnetic resonance (MR) imaging appearance of fetal cerebral ventricles by comparing ultrasonographic (US) and MR images. A retrospective review of MR and US images was performed for 110 normal fetuses and 94 fetuses with central nervous system abnormalities to assess lateral ventricular morphology as having (a) a normal appearance, (b) mild, disproportionate dilatation of the occipital horns with overall preservation of ventricular morphology, (c) colpocephaly with or without normal orientation of the frontal horns, (d) abnormal orientation of the frontal horns without colpocephaly, (e) an angular appearance, (f) fused frontal horns, (g) global dilation, or (h) a distorted appearance. Ventricular morphology on US and MR images was compared and correlated with reference standard diagnoses. US and MR imaging classifications were concordant in 145 of 188 (77%) examinations. Mild disproportion of occipital horns with respect to frontal horns was seen only on MR images. This ventricular configuration was present in eight of 110 normal fetuses and in 10 of 16 fetuses with isolated mild ventriculomegaly (P <.001). An angular configuration of the lateral ventricles, which is seen in fetuses with neural tube defects (NTDs), was present on review of MR images in 11 fetuses and on US images in one fetus. The ventricles of fetuses with NTDs and angular ventricles (3-12 mm) were significantly smaller than those of fetuses with NTDs and global dilatation of the ventricles (13-25 mm; P <.05). Ventricular contours differ with differing diagnoses of central nervous system abnormalities.

  8. Predicting Right Ventricular Failure in the Modern, Continuous Flow Left Ventricular Assist Device Era

    PubMed Central

    Atluri, Pavan; Goldstone, Andrew B.; Fairman, Alex S.; MacArthur, John W.; Shudo, Yasuhiro; Cohen, Jeffrey E.; Acker, Alexandra L.; Hiesinger, William; Howard, Jessica L.; Acker, Michael A.; Woo, Y. Joseph

    2014-01-01

    Background In the era of destination continuous flow left ventricular assist devices (LVAD), the decision of whether a patient will tolerate isolated LVAD support or will need biventricular support (BIVAD) can be challenging. Incorrect decision making with delayed right ventricular (RV) assist device implantation results in increased morbidity and mortality. Continuous flow LVADs have been shown to decrease pulmonary hyper-tension and improve RV function. We undertook this study to determine predictors in the continuous flow LVAD era that identify patients who are candidates for isolated LVAD therapy as opposed to biventricular support. Methods We reviewed demographic, hemodynamic, laboratory, and echocardiographic variables for 218 patients who underwent VAD implant from 2003 through 2011 (LVAD = 167, BIVAD = 51), during the era of continuous flow LVADs. Results Fifty preoperative risk factors were compared between patients who were successfully managed with an LVAD and those who required a BIVAD. Seventeen variables demonstrated statistical significance by univariate analysis. Multivariable logistic regression analysis identified central venous pressure >15 mmHg (OR 2.0, “C”), severe RV dysfunction (OR 3.7, “R”), preoperative intubation (OR 4.3, “I”), severe tricuspid regurgitation (OR 4.1, “T”), heart rate >100 (OR 2.0, Tachycardia - “T”) -CRITT as the major criteria predictive of the need for biventricular support. Utilizing these data, a highly sensitive and easy to use risk score for determining RV failure was generated that outperformed other established risk stratification tools. Conclusions We present a preoperative risk calculator to determine suitability of a patient for isolated LVAD support in the current continuous flow ventricular assist device era. PMID:23791165

  9. Catheter Ablation for Ventricular Arrhythmias

    PubMed Central

    Nof, Eyal; Stevenson, William G; John, Roy M

    2013-01-01

    Catheter ablation has emerged as an important and effective treatment option for many recurrent ventricular arrhythmias. The approach to ablation and the risks and outcomes are largely determined by the nature of the severity and type of underlying heart disease. In patients with structural heart disease, catheter ablation can effectively reduce ventricular tachycardia (VT) episodes and implantable cardioverter defibrillator (ICD) shocks. For VT and symptomatic premature ventricular beats that occur in the absence of structural heart disease, catheter ablation is often effective as the sole therapy. Advances in catheter technology, imaging and mapping techniques have improved success rates for ablation. This review discusses current approaches to mapping and ablation for ventricular arrhythmias. PMID:26835040

  10. Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients.

    PubMed

    Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

    2013-06-07

    As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

  11. Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients

    NASA Astrophysics Data System (ADS)

    Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

    2013-06-01

    As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

  12. Quantification of Left Ventricular Function with Premature Ventricular Complexes Reveals Variable Hemodynamics

    PubMed Central

    Contijoch, Francisco; Rogers, Kelly; Rears, Hannah; Shahid, Mohammed; Kellman, Peter; Gorman, Joseph; Gorman, Robert C.; Yushkevich, Paul; Zado, Erica S.; Supple, Gregory E.; Marchlinski, Francis E.; Witschey, Walter R.T.; Han, Yuchi

    2016-01-01

    Background Premature ventricular complexes (PVC) are prevalent in the general population and are sometimes associated with reduced ventricular function. Current echocardiographic and cardiovascular magnetic resonance imaging (CMR) techniques do not adequately address the effect of PVCs on left ventricular function. Methods and Results Fifteen subjects with a history of frequent PVCs undergoing CMR had real-time slice volume quantification performed using a 2D real-time CMR imaging technique. Synchronization of 2D real-time imaging with patient ECG allowed for different beats to be categorized by the loading beat RR-duration and beat RR-duration. For each beat type, global volumes were quantified via summation over all slices covering the entire ventricle. Different patterns of ectopy including isolated PVCs, bigeminy, trigeminy, and interpolated PVCs were observed. Global functional measurement of the different beat types based on timing demonstrated differences in preload, stroke volume, and ejection fraction. An average of hemodynamic function was quantified for each subject depending on the frequency of each observed beat type. Conclusions Application of real-time CMR imaging in patients with PVCs revealed differential contribution of PVCs to hemodynamics. PMID:27009416

  13. Radiofrequency catheter ablation of ventricular tachycardia in a military parachuter.

    PubMed

    Ozturk, Cengiz; Cakmak, Tolga; Aparci, Mustafa; Metin, Suleyman; Yildirim, Ali Osman

    2013-10-01

    Premature ventricular contractions (PVCs) presenting as isolated complexes are insignificant, but if they present as salvos they are considered indicators of high risk for potentially fatal arrhythmias. We present the case of a 39-yr-old male military parachuter with PVCs and ventricular tachycardia that were incidentally detected on ECG and treated with radiofrequency catheter ablation (RFCA). He had no significant past medical history. Physical examination and biochemical tests were normal. Transthoracic echocardiography showed no structural heart disease. Due to frequent ventricular extrasystoles (VES) detected on his ECG, 24-h Holter monitoring was conducted and revealed VES, including 13,351 isolated PVCs, 1427 episodes of bigeminy, 397 of trigeminy, 30 couplets, and 4 salvo periods. After beta-blocker and calcium channel blocker treatment for 1 mo, his repeat 24-h Holter monitoring showed 18,414 isolated PVCs, 819 episodes of bigeminy, 181 of trigeminy, and 6 couplet VES, but no episodes of salvos. Electrophysiological studies (EPS) were performed and the baseline measurements were: basic cycle length: 890 ms; atrium His interval: 78 ms; and ventricular His interval: 54 ms. VES were found to orginate from the right ventricular outflow tract and were terminated by RFCA. Medical treatment was stopped. Repeat Holter showed no VES. The parachuter was qualified for full duties. As the patient is an aircrew member and further usage of antiarrhythmic agents will interfere with his flying status, instead of initiating a drug therapy again, we performed EPS and RFCA as an effective and dependable method in order to treat and to determine his fitness.

  14. Ventricular assist devices in pediatrics

    PubMed Central

    Fuchs, A; Netz, H

    2001-01-01

    The implantation of a mechanical circulatory device for end-stage ventricular failure is a possible therapeutic approach in adult and pediatric cardiac surgery and cardiology. The aim of this article is to present mechanical circulatory assist devices used in infants and children with special emphasis on extracorporeal membrane oxygenation, Berlin Heart assist device, centrifugal pump and Medos assist device. The success of long-term support with implantable ventricular assist devices in adults and children has led to their increasing use as a bridge to transplantation in patients with otherwise non-treatable left ventricular failure, by transforming a terminal phase heart condition into a treatable cardiopathy. Such therapy allows rehabilitation of patients before elective cardiac transplantation (by removing contraindications to transplantation mainly represented by organ impairment) or acting as a bridge to recovery of the native left ventricular function (depending on underlying cardiac disease). Treatment may also involve permanent device implantation when cardiac transplantation is contraindicated. Indications for the implantation of assisted circulation include all states of cardiac failure that are reversible within a variable period of time or that require heart transplantation. This article will address the current status of ventricular assist devices by examining historical aspects of its development, current technical issues and clinical features of pediatric ventricular assist devices, including indications and contraindications for support. PMID:22368605

  15. The overloaded right heart and ventricular interdependence.

    PubMed

    Naeije, Robert; Badagliacca, Roberto

    2017-10-01

    The right and the left ventricle are interdependent as both structures are nested within the pericardium, have the septum in common and are encircled with common myocardial fibres. Therefore, right ventricular volume or pressure overloading affects left ventricular function, and this in turn may affect the right ventricle. In normal subjects at rest, right ventricular function has negligible interaction with left ventricular function. However, the right ventricle contributes significantly to the normal cardiac output response to exercise. In patients with right ventricular volume overload without pulmonary hypertension, left ventricular diastolic compliance is decreased and ejection fraction depressed but without intrinsic alteration in contractility. In patients with right ventricular pressure overload, left ventricular compliance is decreased with initial preservation of left ventricular ejection fraction, but with eventual left ventricular atrophic remodelling and altered systolic function. Breathing affects ventricular interdependence, in healthy subjects during exercise and in patients with lung diseases and altered respiratory system mechanics. Inspiration increases right ventricular volumes and decreases left ventricular volumes. Expiration decreases both right and left ventricular volumes. The presence of an intact pericardium enhances ventricular diastolic interdependence but has negligible effect on ventricular systolic interdependence. On the other hand, systolic interdependence is enhanced by a stiff right ventricular free wall, and decreased by a stiff septum. Recent imaging studies have shown that both diastolic and systolic ventricular interactions are negatively affected by right ventricular regional inhomogeneity and prolongation of contraction, which occur along with an increase in pulmonary artery pressure. The clinical relevance of these observations is being explored. Published on behalf of the European Society of Cardiology. All rights

  16. Third ventricular meningiomas.

    PubMed

    Li, Puxian; Diao, Xingtao; Bi, Zhiyong; Hao, Shuyu; Ren, Xiaohui; Zhang, Junting; Xing, Jun

    2015-11-01

    We report 13 patients with third ventricular meningiomas (TVM) and discuss the clinical, radiological, pathological and surgical features, as well as follow-up of these tumors. TVM are rare intracranial tumors, and because of this, there are few reports in the literature. Of 11,600 intracranial meningiomas that were surgically treated and pathologically confirmed at Beijing Tian Tan Hospital over a period of 10 years (2003-2013), 13 TVM were selected for a retrospective review. We recorded the clinical, radiological, pathological, and surgical data and statistically analyzed the preoperative, postoperative and 6 month postoperative Karnofsky performance scale (KPS) scores. TVM represented 0.11% of intracranial meningiomas. Radiologically, TVM were divided into three groups: anterior (n=3), posterior (n=3), and entire third ventricle (n=7). Three patients (23.1%) were misdiagnosed preoperatively. Total removal was achieved in 61.5% (8/13) of patients, and subtotal resection was achieved in 38.5% (5/13). Pathologically, the tumors were World Health Organization (WHO) Grade I in 11 patients (84.6%) and WHO Grade II in two (15.6%). There were no statistically significant differences in the preoperative, postoperative, or 6 month postoperative KPS scores (F=0.814; p=0.401). TVM without dural attachments are rare neoplasms that should be differentiated from choroid plexus papilloma, craniopharyngioma, and pineocytoma. Surgery is the optimal treatment and may result in a favorable prognosis, and understanding of the radiological subtype can help with the choice of surgical approach.

  17. Rupture of Right Ventricular Free Wall Following Ventricular Septal Rupture in Takotsubo Cardiomyopathy with Right Ventricular Involvement

    PubMed Central

    Sung, June-Min; Chung, In-Hyun; Lee, Hye Young; Lee, Jae Hoon; Kim, Hyun-Jung; Byun, Young Sup; Kim, Byung Ok; Rhee, Kun Joo

    2017-01-01

    Most patients diagnosed with takotsubo cardiomyopathies are expected to almost completely recover, and their prognosis is excellent. However, complications can occur in the acute phase. We present a case of a woman with takotsubo cardiomyopathy with right ventricular involvement who developed a rupture of the right ventricular free wall following ventricular septal rupture, as a consequence of an acute increase in right ventricular afterload by left-to-right shunt. Our case report illustrates that takotsubo cardiomyopathy can be life threatening in the acute phase. Ventricular septal rupture in biventricular takotsubo cardiomyopathy may be a harbinger of cardiac tamponade by right ventricular rupture. PMID:27873520

  18. Rupture of Right Ventricular Free Wall Following Ventricular Septal Rupture in Takotsubo Cardiomyopathy with Right Ventricular Involvement.

    PubMed

    Sung, June Min; Hong, Sung Jin; Chung, In Hyun; Lee, Hye Young; Lee, Jae Hoon; Kim, Hyun Jung; Byun, Young Sup; Kim, Byung Ok; Rhee, Kun Joo

    2017-01-01

    Most patients diagnosed with takotsubo cardiomyopathies are expected to almost completely recover, and their prognosis is excellent. However, complications can occur in the acute phase. We present a case of a woman with takotsubo cardiomyopathy with right ventricular involvement who developed a rupture of the right ventricular free wall following ventricular septal rupture, as a consequence of an acute increase in right ventricular afterload by left-to-right shunt. Our case report illustrates that takotsubo cardiomyopathy can be life threatening in the acute phase. Ventricular septal rupture in biventricular takotsubo cardiomyopathy may be a harbinger of cardiac tamponade by right ventricular rupture.

  19. Pleiotropic Effects of Myocardial MMP-9 Inhibition to Prevent Ventricular Arrhythmia

    PubMed Central

    Weng, Ching-Hui; Chung, Fa-Po; Chen, Yao-Chang; Lin, Shien-Fong; Huang, Po-Hsun; Kuo, Terry B. J.; Hsu, Wei-Hsuan; Su, Wen-Cheng; Sung, Yen-Ling; Lin, Yenn-Jiang; Chang, Shih-Lin; Lo, Li-Wei; Yeh, Hung-I; Chen, Yi-Jen; Hong, Yi-Ren; Chen, Shih-Ann; Hu, Yu-Feng

    2016-01-01

    Observational studies have established a strong association between matrix metalloproteinase-9 (MMP-9) and ventricular arrhythmia. However, whether MMP-9 has a causal link to ventricular arrhythmia, as well as the underlying mechanism, remains unclear. Here, we investigated the mechanistic involvement of myocardial MMP-9 in the pathophysiology of ventricular arrhythmia. Increased levels of myocardial MMP-9 are linked to ventricular arrhythmia attacks after angiotensin II (Ang II) treatment. MMP-9-deficient mice were protected from ventricular arrhythmia. Increased expressions of protein kinase A (PKA) and ryanodine receptor phosphorylation at serine 2808 (pS2808) were correlated with inducible ventricular arrhythmia. MMP-9 deficiency consistently prevented PKA and pS2808 increases after Ang II treatment and reduced ventricular arrhythmia. Calcium dynamics were examined via confocal imaging in isolated murine cardiomyocytes. MMP-9 inhibition prevents calcium leakage from the sarcoplasmic reticulum and reduces arrhythmia-like irregular calcium transients via protein kinase A and ryanodine receptor phosphorylation. Human induced pluripotent stem cell-derived cardiomyocytes similarly show that MMP-9 inhibition prevents abnormal calcium leakage. Myocardial MMP-9 inhibition prevents ventricular arrhythmia through pleiotropic effects, including the modulation of calcium homeostasis and reduced calcium leakage. PMID:27966586

  20. Right-to-left ventricular end-diastolic diameter ratio and prediction of right ventricular failure with continuous-flow left ventricular assist devices.

    PubMed

    Kukucka, Marian; Stepanenko, Alexander; Potapov, Evgenij; Krabatsch, Thomas; Redlin, Mathias; Mladenow, Alexander; Kuppe, Hermann; Hetzer, Roland; Habazettl, Helmut

    2011-01-01

    Left ventricular assist device (LVAD) implantation is an accepted therapy for patients with end-stage heart failure. Post-operative right ventricular failure (RVF) still remains a major cause of morbidity and mortality in these patients. This study sought to identify echocardiography parameters to select patients with high risk of RVF after LVAD implantation. Prospectively collected pre-operative transesophageal echocardiography (TEE) and clinical data were evaluated in patients pre-selected for isolated LVAD or biventricular assist device (BiVAD) implantation. According to prevalence of RVF during the first post-operative 48 hours, patients were divided into those who developed RVF (isolated LVAD with RVF) and those who did not (isolated LVAD without RVF). Echocardiographic parameters for RV geometry, RV function, LV geometry, and the RV-to-LV end-diastolic diameter ratio (R/L ratio) were evaluated. For identification of the optimal cutoff of R/L ratio, receiver operating characteristics curves were constructed. An isolated LVAD was implanted in 115 patients and BiVAD in 22 patients. RVF developed in 15 patients (13%) after isolated LVAD implantation. The R/L ratio was markedly increased in the isolated LVAD with RVF and BiVAD groups compared with the isolated LVAD without RVF group. According to the receiving operating curve, the cutoff for the R/L ratio to predict RVF was 0.72. The odds ratio that RVF will develop is 11.4 in patients with an R/L ratio >0.72 (p = 0.0001). Increased R/L ratio successfully identifies patients with high risk of RVF after isolated LVAD implantation. Beyond standard measurements of RV function, the consideration of R/L ratio may be useful to improve risk stratification in patients before isolated LVAD implantation. Copyright © 2011 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  1. Pediatric ventricular assist devices

    PubMed Central

    Burki, Sarah; Zafar, Farhan; Morales, David Luis Simon

    2015-01-01

    The domain of pediatric ventricular assist device (VAD) has recently gained considerable attention. Despite the fact that, historically, the practice of pediatric mechanical circulatory support (MCS) has lagged behind that of adult patients, this gap between the two groups is narrowing. Currently, the Berlin EXCOR VAD is the only pediatric-specific durable VAD approved by the U.S Food and Drug Administration (FDA). The prospective Berlin Heart trial demonstrated a successful outcome, either bridge to transplantation (BTT), or in rare instances, bridge to recovery, in approximately 90% of children. Also noted during the trial was, however, a high incidence of adverse events such as embolic stroke, bleeding and infection. This has incentivized some pediatric centers to utilize adult implantable continuous-flow devices, for instance the HeartMate II and HeartWare HVAD, in children. As a result of this paradigm shift, the outlook of pediatric VAD support has dramatically changed: Treatment options previously unavailable to children, including outpatient management and even destination therapy, have now been becoming a reality. The sustained demand for continued device miniaturization and technological refinements is anticipated to extend the range of options available to children—HeartMate 3 and HeartWare MVAD are two examples of next generation VADs with potential pediatric application, both of which are presently undergoing clinical trials. A pediatric-specific continuous-flow device is also on the horizon: the redesigned Infant Jarvik VAD (Jarvik 2015) is undergoing pre-clinical testing, with a randomized clinical trial anticipated to follow thereafter. The era of pediatric VADs has begun. In this article, we discuss several important aspects of contemporary VAD therapy, with a particular focus on challenges unique to the pediatric population. PMID:26793341

  2. Disseminated Streptococcus pneumoniae infection involving a ventricular assist device

    PubMed Central

    Reeves, J.S.; Rajagopalan, N.; Huaman, M.A.

    2015-01-01

    We describe the first reported case, to our knowledge, of disseminated pneumococcal infection involving a left ventricular assist device (LVAD). The management of this infection was extremely challenging, requiring multiple surgical debridements, LVAD removal, and prolonged courses of antibiotics. The Streptococcus pneumoniae isolate was found to be serotype 19F, which is included in both the pneumococcal polysaccharide and conjugate vaccines. This report highlights the importance of routine screening for up-to-date vaccination in patients who undergo LVAD implantation. PMID:26073334

  3. Disseminated Streptococcus pneumoniae infection involving a ventricular assist device.

    PubMed

    Reeves, J S; Rajagopalan, N; Huaman, M A

    2015-08-01

    We describe the first reported case, to our knowledge, of disseminated pneumococcal infection involving a left ventricular assist device (LVAD). The management of this infection was extremely challenging, requiring multiple surgical debridements, LVAD removal, and prolonged courses of antibiotics. The Streptococcus pneumoniae isolate was found to be serotype 19F, which is included in both the pneumococcal polysaccharide and conjugate vaccines. This report highlights the importance of routine screening for up-to-date vaccination in patients who undergo LVAD implantation.

  4. Spontaneous Ventricular Fibrillation in Right Ventricular Failure Secondary to Chronic Pulmonary Hypertension

    PubMed Central

    Umar, Soban; Lee, Jong-Hwan; de Lange, Enno; Iorga, Andrea; Partow-Navid, Rod; Bapat, Aneesh; van der Laarse, Arnoud; Saggar, Rajeev; Saggar, Rajan; Ypey, Dirk L.; Karagueuzian, Hrayr S.; Eghbali, Mansoureh

    2012-01-01

    Background Right ventricular failure (RVF) in pulmonary hypertension (PH) is associated with increased incidence of sudden death by a poorly explored mechanism. Here we test the hypothesis that PH promotes spontaneous ventricular fibrillation (VF) during a critical post-PH onset period characterized by a sudden increase in mortality. Methods and Results Rats received either a single subcutaneous dose of monocrotaline (MCT, 60 mg/kg) to induce PH-associated RVF (PH, n=24) or saline (CTRL, n=17). Activation pattern of RV-epicardial surface was mapped using voltage-sensitive dye in isolated Langendorff-perfused hearts along with single glass-microelectrode and ECG-recordings. MCT-injected rats developed severe PH by day-21 and progressed to RVF by ~day-30. Rats manifested increased mortality and ~30% rats died suddenly and precipitously during 23–32 days post-MCT. This fatal period was associated with the initiation of spontaneous VF by a focal mechanism in the RV which was subsequently maintained by both focal and incomplete re-entrant wavefronts. Microelectrode recordings from the RV-epicardium at the onset of focal activity showed early afterdepolarization (EAD)-mediated triggered activity that led to VF. The onset of the RV cellular triggered beats preceded left ventricular depolarizations by 23±8 ms. The RV but not the LV cardiomyocytes isolated during this fatal period manifested significant action potential duration prolongation, dispersion and an increased susceptibility to depolarization-induced repetitive activity. No spontaneous VF was observed in any of the CTRL hearts. RVF was associated with significantly reduced RV ejection fraction (p<0.001), RV hypertrophy (p<0.001) and RV fibrosis (p<0.01). The hemodynamic function of the LV and its structure were preserved. Conclusions PH-induced RVF is associated with a distinct phase of increased mortality characterized by spontaneous VF arising from the RV by an EAD-mediated triggered activity. PMID:22199010

  5. Epicardial Ablation of Ventricular Tachycardia

    PubMed Central

    Tung, Roderick; Shivkumar, Kalyanam

    2015-01-01

    Epicardial mapping and ablation via a percutaneous subxiphoid technique has been instrumental in improving the working understanding of complex myocardial scars in various arrhythmogenic substrates. Endocardial ablation alone may not be sufficient in patients with ischemic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, and Chagas disease to prevent recurrent ventricular tachycardia. Multiple observational studies have demonstrated greater freedom from recurrence with adjunctive epicardial ablation compared with endocardial ablation alone. While epicardial ablation is performed predominantly at tertiary referral centers, knowledge of the technical approach, clinical indications, and potential complications is imperative to maximizing clinical success and patient safety. In 1996, Sosa and colleagues modified the pericardiocentesis technique to enable percutaneous access to the pericardial space for mapping and catheter ablation of ventricular tachycardia.1 Originally developed for patients with epicardial scarring due to chagasic cardiomyopathy and patients with ischemic cardiomyopathy refractory to endocardial ablationm,2,3 this approach has since become an essential part of the armamentarium for the treatment of ventricular tachycardia. Myocardial scars are three-dimensionally complex with varying degrees of transmurality, and the ability to map and ablate the epicardial surface has contributed to a greater understanding of scar-related VT in postinfarction cardiomyopathy and nonischemic substrates including idiopathic dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, and chagasic cardiomyopathy. In this review, we highlight the percutaneous approach and discuss clinical indications and potential complications. PMID:26306131

  6. Epicardial Ablation of Ventricular Tachycardia.

    PubMed

    Tung, Roderick; Shivkumar, Kalyanam

    2015-01-01

    Epicardial mapping and ablation via a percutaneous subxiphoid technique has been instrumental in improving the working understanding of complex myocardial scars in various arrhythmogenic substrates. Endocardial ablation alone may not be sufficient in patients with ischemic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, and Chagas disease to prevent recurrent ventricular tachycardia. Multiple observational studies have demonstrated greater freedom from recurrence with adjunctive epicardial ablation compared with endocardial ablation alone. While epicardial ablation is performed predominantly at tertiary referral centers, knowledge of the technical approach, clinical indications, and potential complications is imperative to maximizing clinical success and patient safety. In 1996, Sosa and colleagues modified the pericardiocentesis technique to enable percutaneous access to the pericardial space for mapping and catheter ablation of ventricular tachycardia.1 Originally developed for patients with epicardial scarring due to chagasic cardiomyopathy and patients with ischemic cardiomyopathy refractory to endocardial ablationm,2,3 this approach has since become an essential part of the armamentarium for the treatment of ventricular tachycardia. Myocardial scars are three-dimensionally complex with varying degrees of transmurality, and the ability to map and ablate the epicardial surface has contributed to a greater understanding of scar-related VT in postinfarction cardiomyopathy and nonischemic substrates including idiopathic dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, and chagasic cardiomyopathy. In this review, we highlight the percutaneous approach and discuss clinical indications and potential complications.

  7. Moexipril and left ventricular hypertrophy.

    PubMed

    Chrysant, George S; Nguyen, P K

    2007-01-01

    Angiotensin-converting enzyme (ACE) inhibitors today are the standard therapy of patients with myocardial infarction and heart failure due to their proven beneficial effects in left ventricular remodeling and left ventricular function. ACE inhibitors have also been demonstrated to lead to regression of left ventricular hypertrophy (LVH). It is believed that the mechanism of action of LVH regression with ACE inhibitors arises from more than simple blood pressure reduction. LVH is an important risk factor for cardiovascular disease morbidity and mortality independent of blood pressure. Moexipril hydrochloride is a long-acting, non-sulfhydryl ACE inhibitor that can be taken once daily for the treatment of hypertension. Moexipril has now also been demonstrated to have beneficial effects on LVH and can lead to LVH regression.

  8. Moexipril and left ventricular hypertrophy

    PubMed Central

    Chrysant, George S; Nguyen, PK

    2007-01-01

    Angiotensin-converting enzyme (ACE) inhibitors today are the standard therapy of patients with myocardial infarction and heart failure due to their proven beneficial effects in left ventricular remodeling and left ventricular function. ACE inhibitors have also been demonstrated to lead to regression of left ventricular hypertrophy (LVH). It is believed that the mechanism of action of LVH regression with ACE inhibitors arises from more than simple blood pressure reduction. LVH is an important risk factor for cardiovascular disease morbidity and mortality independent of blood pressure. Moexipril hydrochloride is a long-acting, non-sulfhydryl ACE inhibitor that can be taken once daily for the treatment of hypertension. Moexipril has now also been demonstrated to have beneficial effects on LVH and can lead to LVH regression. PMID:17583172

  9. An Unusual Etiology for Bidirectional Ventricular Tachycardia.

    PubMed

    Zhao, Yun-Tao; Wang, Lei; Yi, Zhong

    2016-03-01

    Bidirectional ventricular tachycardia is a rare variety of tachycardia with a morphologically distinct presentation. The QRS axis and/or morphology alternate in the frontal plane leads. We report a patient with bidirectional ventricular tachycardia in association with aconitine poisoning.

  10. Analysis of Ventricular Function by Computed Tomography

    PubMed Central

    Rizvi, Asim; Deaño, Roderick C.; Bachman, Daniel P.; Xiong, Guanglei; Min, James K.; Truong, Quynh A.

    2014-01-01

    The assessment of ventricular function, cardiac chamber dimensions and ventricular mass is fundamental for clinical diagnosis, risk assessment, therapeutic decisions, and prognosis in patients with cardiac disease. Although cardiac computed tomography (CT) is a noninvasive imaging technique often used for the assessment of coronary artery disease, it can also be utilized to obtain important data about left and right ventricular function and morphology. In this review, we will discuss the clinical indications for the use of cardiac CT for ventricular analysis, review the evidence on the assessment of ventricular function compared to existing imaging modalities such cardiac MRI and echocardiography, provide a typical cardiac CT protocol for image acquisition and post-processing for ventricular analysis, and provide step-by-step instructions to acquire multiplanar cardiac views for ventricular assessment from the standard axial, coronal, and sagittal planes. Furthermore, both qualitative and quantitative assessments of ventricular function as well as sample reporting are detailed. PMID:25576407

  11. Sertraline-induced ventricular tachycardia.

    PubMed

    Patel, Nishit H; Golwala, Harsh; Stavrakis, Stavros; Schechter, Eliot

    2013-01-01

    Sertraline is a selective serotonin reuptake inhibitor, which is a commonly used drug for major depressive disorder. Most frequently reported adverse effects of sertraline in patients receiving 50-150 mg/d are dry mouth, headache, diarrhea, nausea, vomiting, sweating, and dizziness. We hereby report one of the few cases of sertraline-induced ventricular tachycardia, which has been for the first time objectively assessed by the Naranjo scale. We therefore urge the primary care physicians and the cardiologists to keep sertraline as a possible precipitating factor for evaluation of ventricular tachycardia.

  12. Nonlinear dynamics in ventricular fibrillation.

    PubMed Central

    Hastings, H M; Evans, S J; Quan, W; Chong, M L; Nwasokwa, O

    1996-01-01

    Electrogram recordings of ventricular fibrillation appear complex and possibly chaotic. However, sequences of beat-to-beat intervals obtained from these recordings are generally short, making it difficult to explicitly demonstrate nonlinear dynamics. Motivated by the work of Sugihara on atmospheric dynamics and the Durbin-Watson test for nonlinearity, we introduce a new statistical test that recovers significant dynamical patterns from smoothed lag plots. This test is used to show highly significant nonlinear dynamics in a stable canine model of ventricular fibrillation. Images Fig. 3 PMID:8816831

  13. [Right ventricular assessment with echocardiography].

    PubMed

    Fayssoil, Abdallah; Abasse, Soumeth; Nardi, Olivier

    2009-05-01

    Right ventricular (RV) function is essential in cardio--pulmonary physiology and physiopathology. RV dysfunction has prognostic impact in inferior myocardial infarction, significant valvulopathies, congenital cardiopathies, arterial pulmonary hypertension and in patients suffering from acute or chronic heart failure. RV analysis relies on non invasive (echocardiography-Doppler, isotopic technology, cardiac magnetic resonance imaging) and/or invasive approaches (right cardiac catheterization). Neglected a short time ago, RV assessment has regained interest with tissular Doppler imaging, strain imaging and 2D speckle tracking. We review echocardiography and Doppler -parameters used for right -ventricular assessment.

  14. Right ventricular outflow obstruction with intact ventricular septum in adults.

    PubMed Central

    Werner, A M; Darrell, J C; Pallegrini, R V; Woelfel, G F; Grant, K; Marrangoni, A G

    1997-01-01

    Cardiothoracic surgeons whose practice is limited to adults rarely see patients with right ventricular outflow obstruction and an intact ventricular septum. Of more than 10,000 open-heart procedures performed at our institution from 1983 to 1993 (in patients 18 to 75 years old), only 5 procedures were for correction of this problem. Both the pulmonary valve and the subvalvular area were abnormal in these 5 patients, and 4 of the 5 had subvalvular stenosis. The gradient across the right ventricular outflow tract was measured by cardiac catheterization before repair in all patients and averaged 118 mmHg. Various surgical approaches were used for repair. In the 2 patients whose pressures were measured postoperatively, the gradients were 25 mmHg and 45 mmHg, respectively. There were no operative deaths. At follow-up (range, 2 months to 5 years after surgery), all patients were in New York Heart Association functional class I and all had murmurs. Those who underwent echocardiography were found to have minimal gradients across the right ventricular outflow tract. Images PMID:9205983

  15. Allicin inhibits transient outward potassium currents in mouse ventricular myocytes.

    PubMed

    Cao, Hong; Huang, Congxin; Wang, Xin

    2016-05-01

    Allicin is the active constituent of garlic, a widely used spice and food. The remedial properties of garlic have also been extensively researched and it has been demonstrated that allicin is able to inhibit the transient outward potassium current (Ito) in atrial myocytes. However, the direct effect of allicin on Ito in ventricular myocytes has yet to be elucidated. In the present study, the effects of allicin on Ito in ventricular myocytes isolated from mice were investigated, using the whole-cell patch recording technique. The results revealed that Ito current was not significantly suppressed by allicin in the low-dose group (10 µmol/l; P>0.05). However, Ito was significantly inhibited by higher doses of allicin (30, 100 and 300 µmol/l; P<0.05 vs. control; n=6) in a concentration-dependent manner (IC50=41.6 µmol/l). In addition, a high concentration of allicin (≥100 µmol/l) was able to accelerate the voltage-dependent inactivation of Ito in mouse ventricular myocytes. In conclusion, the present study revealed that allicin inhibited the Ito in mouse ventricular myocytes, which may be the mechanism through which allicin exerts its antiarrhythmic effect.

  16. Allicin inhibits transient outward potassium currents in mouse ventricular myocytes

    PubMed Central

    CAO, HONG; HUANG, CONGXIN; WANG, XIN

    2016-01-01

    Allicin is the active constituent of garlic, a widely used spice and food. The remedial properties of garlic have also been extensively researched and it has been demonstrated that allicin is able to inhibit the transient outward potassium current (Ito) in atrial myocytes. However, the direct effect of allicin on Ito in ventricular myocytes has yet to be elucidated. In the present study, the effects of allicin on Ito in ventricular myocytes isolated from mice were investigated, using the whole-cell patch recording technique. The results revealed that Ito current was not significantly suppressed by allicin in the low-dose group (10 µmol/l; P>0.05). However, Ito was significantly inhibited by higher doses of allicin (30, 100 and 300 µmol/l; P<0.05 vs. control; n=6) in a concentration-dependent manner (IC50=41.6 µmol/l). In addition, a high concentration of allicin (≥100 µmol/l) was able to accelerate the voltage-dependent inactivation of Ito in mouse ventricular myocytes. In conclusion, the present study revealed that allicin inhibited the Ito in mouse ventricular myocytes, which may be the mechanism through which allicin exerts its antiarrhythmic effect. PMID:27168824

  17. Diagnosis and prognosis of right ventricular infarction.

    PubMed Central

    Rodrigues, E A; Dewhurst, N G; Smart, L M; Hannan, W J; Muir, A L

    1986-01-01

    The values of several non-invasive methods for the diagnosis of right ventricular necrosis in inferior myocardial infarction were compared in 51 consecutive patients who underwent serial radionuclide ventriculography, pyrophosphate scintigraphy, and cross sectional echocardiography. In addition a unipolar electrocardiographic lead V4R was recorded on admission, daily, and during episodes of further pain. Profound right ventricular dysfunction was evident in 50% of patients studied by radionuclide methods after inferior myocardial infarction but recognition on clinical groups alone was poor. Functionally important right ventricular infarction was best detected and followed serially by radionuclide ventriculography. Echocardiographic methods for evaluating right ventricular ejection fraction correlated poorly with radionuclide methods. Increased uptake of radioactivity by the right ventricle on pyrophosphate scintigraphy usually indicated poor right ventricular function, but a scan that was negative in the right ventricular territory did not exclude dysfunction. ST segment elevation in V4R was not specific for right ventricular infarction and its routine use may lead to overdiagnosis of this condition. Serial measurements suggest that profound right ventricular dysfunction persists after acute inferior infarction and is associated with considerable morbidity and mortality. Of 25 patients with severe right ventricular dysfunction, six died in the late hospital period. In the remaining 19 patients mean right ventricular ejection fraction over a two month period did not improve; six patients had persistent right ventricular dyskinesia and features of chronic right ventricular failure developed in three survivors. Images Fig. 1 PMID:3015175

  18. Diffuse ventricular fibrosis measured by T₁ mapping on cardiac MRI predicts success of catheter ablation for atrial fibrillation.

    PubMed

    McLellan, Alex J A; Ling, Liang-han; Azzopardi, Sonia; Ellims, Andris H; Iles, Leah M; Sellenger, Michael A; Morton, Joseph B; Kalman, Jonathan M; Taylor, Andrew J; Kistler, Peter M

    2014-10-01

    There is a complex interplay between the atria and ventricles in atrial fibrillation (AF). Cardiac magnetic resonance (CMR) imaging provides detailed tissue characterization, identifying focal ventricular fibrosis with late gadolinium enhancement (ventricular late gadolinium enhancement) and diffuse fibrosis with postcontrast-enhanced T1 mapping. The aim of the present study was to investigate the relationship between postcontrast ventricular T1 relaxation time on CMR and freedom from AF after pulmonary vein isolation. One hundred three patients undergoing catheter ablation for symptomatic AF (66% paroxysmal AF; age, 58±10 years; left atrial area, 27±7 cm(2)) underwent preprocedure CMR to determine postcontrast ventricular T1 time. Follow-up included clinical review and 7-day Holter monitors at 6 monthly intervals. All patients underwent successful pulmonary vein isolation. At a mean follow-up of 15±7 months, the single procedure success was 74%. Postcontrast ventricular T1 time was significantly shorter in patients with recurrent AF (366±73 ms) versus patients without AF recurrence (428±90 ms; P=0.002). Univariate predictors of AF recurrence included postcontrast ventricular T1 time, AF type (paroxysmal versus persistent), AF duration, and body mass index. After multivariate analysis, ventricular T1 time (P=0.03) and AF duration (P=0.03) were the only independent predictors. Freedom from AF was present in 84% of patients with a postcontrast ventricular T1 time >380 ms versus 56% in patients with a postcontrast ventricular T1 time <380 ms (P=0.002). A shorter postcontrast ventricular T1 relaxation time on CMR is associated with reduced freedom from AF after catheter ablation. Diffuse ventricular fibrosis as demonstrated by CMR may, in part, explain recurrent AF after AF ablation. © 2014 American Heart Association, Inc.

  19. Facts about Ventricular Septal Defect

    MedlinePlus

    ... the lungs forces the heart and lungs to work harder. Over time, if not repaired, this defect can increase the risk for other complications, including heart failure, high blood pressure in the lungs ... » Types of Ventricular Septal Defects Click here to ...

  20. Epicardial catheter ablation of ventricular tachycardia in no entry left ventricle: mechanical aortic and mitral valves.

    PubMed

    Soejima, Kyoko; Nogami, Akihiko; Sekiguchi, Yukio; Harada, Tomoo; Satomi, Kazuhiro; Hirose, Takeshi; Ueda, Akiko; Miwa, Yousuke; Sato, Toshiaki; Nishio, Satoru; Shirai, Yasuhiro; Kowase, Shinya; Murakoshi, Nobuyuki; Kunugi, Shinobu; Murata, Hiroshige; Nitta, Takashi; Aonuma, Kazutaka; Yoshino, Hideaki

    2015-04-01

    In patients with mechanical aortic and mitral valves and left ventricular tachycardia, catheter ablation may be prevented by limited access to the left ventricle. In our series of 6 patients, 2 patients underwent direct surgical ablation and 4 underwent epicardial catheter ablation via a pericardial window. All patients had abnormal low voltage areas with fractionated or delayed isolated potentials on the apical epicardium. Most of the ventricular tachycardias were targeted by pace mapping. Sites with a good pace match or abnormal electrograms were ablated using an irrigated radiofrequency ablation catheter. A microscopic pathological evaluation of the resected tissue from 2 of the open-heart ablation patients revealed dense fibrosis on the epicardium compared with the endocardium, supporting the feasibility of an epicardial ablation for the ventricular tachycardia. Epicardial catheter ablation of ventricular tachycardia is a potentially useful therapy in patients who have mechanical aortic and mitral valves. © 2015 American Heart Association, Inc.

  1. Structured prediction for differentiating between normal rhythms, ventricular tachycardia, and ventricular fibrillation in the ECG.

    PubMed

    Alwan, Yaqub; Cvetkovic, Zoran; Curtis, Michael

    2015-01-01

    Recent studies have been performed on feature selection for diagnostics between non-ventricular rhythms and ventricular arrhythmias, or between non-ventricular fibrillation and ventricular fibrillation. However they did not assess classification directly between non-ventricular rhythms, ventricular tachycardia and ventricular fibrillation, which is important in both a clinical setting and preclinical drug discovery. In this study it is shown that in a direct multiclass setting, the selected features from these studies are not capable at differentiating between ventricular tachycardia and ventricular fibrillation. A high dimensional feature space, Fourier magnitude spectra, is proposed for classification, in combination with the structured prediction method conditional random fields. An improvement in overall accuracy, and sensitivity of every category under investigation is achieved.

  2. Percutaneous Left Ventricular Assist Devices in Ventricular Tachycardia Ablation

    PubMed Central

    Reddy, Yeruva Madhu; Chinitz, Larry; Mansour, Moussa; Bunch, T. Jared; Mahapatra, Srijoy; Swarup, Vijay; Di Biase, Luigi; Bommana, Sudharani; Atkins, Donita; Tung, Roderick; Shivkumar, Kalyanam; Burkhardt, J. David; Ruskin, Jeremy; Natale, Andrea; Lakkireddy, Dhanunjaya

    2015-01-01

    Background Data on relative safety, efficacy, and role of different percutaneous left ventricular assist devices for hemodynamic support during the ventricular tachycardia (VT) ablation procedure are limited. Methods and Results We performed a multicenter, observational study from a prospective registry including all consecutive patients (N=66) undergoing VT ablation with a percutaneous left ventricular assist devices in 6 centers in the United States. Patients with intra-aortic balloon pump (IABP group; N=22) were compared with patients with either an Impella or a TandemHeart device (non-IABP group; N=44). There were no significant differences in the baseline characteristics between both the groups. In non-IABP group (1) more patients could undergo entrainment/activation mapping (82% versus 59%; P=0.046), (2) more number of unstable VTs could be mapped and ablated per patient (1.05±0.78 versus 0.32±0.48; P<0.001), (3) more number of VTs could be terminated by ablation (1.59±1.0 versus 0.91±0.81; P=0.007), and (4) fewer VTs were terminated with rescue shocks (1.9±2.2 versus 3.0±1.5; P=0.049) when compared with IABP group. Complications of the procedure trended to be more in the non-IABP group when compared with those in the IABP group (32% versus 14%; P=0.143). Intermediate term outcomes (mortality and VT recurrence) during 12±5-month follow-up were not different between both groups. Left ventricular ejection fraction ≤15% was a strong and independent predictor of in-hospital mortality (53% versus 4%; P<0.001). Conclusions Impella and TandemHeart use in VT ablation facilitates extensive activation mapping of several unstable VTs and requires fewer rescue shocks during the procedure when compared with using IABP. PMID:24532564

  3. Dynamic ventricular overdrive stimulation in atrial fibrillation: effects on ventricular rate irregularity, ventricular pacing, and fusion beats.

    PubMed

    Nölker, Georg; Gutleben, Klaus-Jürgen; Asbach, Stefan; Ritscher, Guido; Marschang, Harald; Sinha, Anil M; Boileau, Peter; Benser, Michael E; Hallier, Benoit; Hümmer, Alexander; Brachmann, Johannes

    2011-12-01

    In pacemaker patients with preserved atrio-ventricular (AV) conduction, atrial fibrillation (AF) can lead to symptomatic ventricular rate irregularity and loss of ventricular stimulation. We tested if dynamic ventricular overdrive (DVO) as a potentially pacemaker-integrated algorithm could improve both aspects. Different settings of DVO and ventricular-ventricular-inhibited-pacing (VVI) with different base rates were tested in two consecutive phases during electrophysiological studies for standard indications. Mean heart rate (HR), HR irregularity and percentage of ventricular pacing were evaluated. A fusion index (FI) indicative of the proportion of fusion beats was calculated for each stimulation protocol. Dynamic ventricular overdrive from the right ventricular apex was acutely applied in 38 patients (11 females, mean age 62.1 ± 11.5 years) with sustained AF and preserved AV conduction. Dynamic ventricular overdrive at LOW/MEDIUM setting increased the amount of ventricular pacing compared with VVI pacing at 60, 70, and 80 beats per minute (bpm; to 81/85% from 11, 25, and 47%, respectively; P < 0.05). It also resulted in a maximum decrease in interval differences (to 48 ± 18 ms from 149 ± 28, 117 ± 38, and 95 ± 46 ms, respectively; P < 0.05) and fusion (to 0.13 from 0.41, 0.42, and 0.36, respectively; P < 0.05) compared with VVI pacing at 60, 70, and 80 bpm. However, the application of DVO resulted in a significant increase in HR compared with intrinsic rhythm and VVI pacing at 80 bpm (to 97 bpm from 89 and 94 bpm, respectively; P < 0.05). Dynamic ventricular overdrive decreases HR irregularity and increases ventricular pacing rate compared with VVI pacing at fixed elevated base rates and spontaneous rhythm. Fusion index might help to refine information on pacing percentages provided by device counters.

  4. [Myocardial ischemia and ventricular arrhythmia].

    PubMed

    Vester, E G

    1998-01-01

    A relation between myocardial ischemia and induction of ventricular arrhythmias can be demonstrated in patients with coronary heart disease--in contrast to patients with primary non ischemic cardiac diseases--using a combined metabolic-electrophysiological investigation protocol consisting of programmed atrial and ventricular stimulation with simultaneous measurement of the arterio/coronary venous difference for lactate, pyruvate, free fatty acids and amino acids. There are significant metabolic distinctions between both ischemic and non ischemic heart disease under pacing stress conditions as well as at rest. Areas of "hibernating myocardium" resp. "mismatch" zones in the myocardium showing reduced or abolished perfusion and preserved metabolism during scintographic SPECT/PET studies, may be found more often in patients with ventricular tachycardias (VT) or ventricular fibrillation (VF) in the chronic post myocardial infarction state than in patients without VT/VF. The proof of such zones may be considered a possible risk factor for arrhythmic events and sudden cardiac death after myocardial infarction. Hereby the concept of an interaction between acute and chronic ischemia triggering the onset of polymorphic VT or VF gaines increasing acceptance. In contrast, monomorphic reentrant VT are usually generated in the border zone of scarred areas where islands of vital fibers are surrounded by fibrotic tissue. These arrhythmogenic origin regions are characterized by a "match" pattern presenting a comparably severe reduction of perfusion and metabolism. Under those circumstances a control resp. suppression of the VT focus can only be provided by interventional techniques like catheter ablation, antitachycardiac surgery or implantation of a cardioverter/defibrillator beyond antiarrhythmic drug therapy. An antiischemic causal treatment (bypass surgery or angioplasty) represents for maximal 40% of patients with ischemically induced ventricular arrhythmias an adequate and

  5. Characteristics of chaotic processes in electrocardiographically identified ventricular arrhythmia.

    PubMed

    Mysiak, Andrzej; Kobusiak-Prokopowicz, Małgorzata; Kaaz, Konrad; Jarczewska, Kamila; Glabisz, Wojciech

    2017-01-01

    The theory of chaos proves a deterministic mechanism of induction of multiple complex processes previously thought to be random in nature. This research explains how these complex processes develop. The aim of the study was to test the hypothesis of the chaotic nature of myocardial electrical events during ventricular tachycardia (VT) and ventricular fibrillation (VF). Original hardware and software was developed for digitalization of on-line electrocardiography (ECG) data, with the functions of automatic and manual identification as well as categoriza-tion of specific ventricular arrhythmias. Patient ECGs were recorded by specially developed measuring equipment (M2TT). Available ECG sampling frequency was 20,000 Hz, and it was possible to analyze the signal retrospectively. Digital ECG of the sinus rhythm (SR) was analyzed with non-sustained VT, VT and VF. The signals were then subjected to mathematical analysis. Using wavelet analysis, signals carrying frequencies from various ranges were isolated from baseline and each of these isolated signals was subjected to Fourier transformation to check on differences in the Fourier power spectra of the analyzed VT and VF signals. Ventricular tachycardia identified based on ECG fulfills the criteria of a chaotic process, while no such properties were found for SR and VF. Information obtained by the ECG is used to record myo-cardial electrical signals, but they are not sufficient to differentiate between an advanced chaotic state and the process of linear expansion of electrical activation within the myocardium. Electrophysiological study requires advanced methods to record the signal of myocardial electrical activity, as ECG is not sufficiently sensitive to identify the features of a chaotic process during VF. (Cardiol J 2017; 24, 2: 151-158).

  6. Regional myocardial shape and dimensions of the working isolated canine left ventricle

    NASA Technical Reports Server (NTRS)

    Ritman, E. L.; Tsuiki, K.; Donald, D.; Wood, E. H.

    1975-01-01

    The extent to which the dynamic shape and dimensions of the isolated left ventricular myocardial wall differ throughout the myocardium and how these differences are characteristic of the anatomic location was demonstrated. The use of a biplane X-ray technique and a metabolically-supported isolated canine left ventricle preparation provided an angiographically ideal means of measuring mechanical dynamics of the myocardium while the intact left ventricular myocardial structure and electrical activation pattern retains most of the in situ ventricular characteristics.

  7. Aerodynamic and Acoustic Effects of Ventricular Gap

    PubMed Central

    Alipour, Fariborz; Karnell, Michael

    2013-01-01

    Purpose Supraglottic compression is frequently observed in individuals with dysphonia. It is commonly interpreted as an indication of excessive circumlaryngeal muscular tension and ventricular medialization. The purpose of this study was to describe the aerodynamic and acoustic impact of varying ventricular medialization in a canine model. Methods Subglottal air pressure, glottal airflow, electroglottograph, acoustic signals and high-speed video images were recorded in seven excised canine larynges mounted in vitro for laryngeal vibratory experimentation. The degree of gap between the ventricular folds was adjusted and measured using sutures and weights. Data was recorded during phonation when the ventricular gap was narrow, neutral, and large. Glottal resistance was estimated by measures of subglottal pressure and glottal flow. Results Glottal resistance increased systematically as ventricular gap became smaller. Wide ventricular gaps were associated with increases in fundamental frequency and decreases in glottal resistance. Sound pressure level did not appear to be impacted by the adjustments in ventricular gap used in this research. Conclusions Increases in supraglottic compression and associated reduced ventricular width may be observed in a variety of disorders that affect voice quality. Ventricular compression may interact with true vocal fold posture and vibration resulting in predictable changes in aerodynamic, physiologic, acoustic, and perceptual measures of phonation. The data from this report supports the theory that narrow ventricular gaps may be associated with disordered phonation. In vitro and in vivo human data are needed to further test this association. PMID:24321590

  8. Analysing the ventricular fibrillation waveform.

    PubMed

    Reed, Matthew J; Clegg, Gareth R; Robertson, Colin E

    2003-04-01

    The surface electrocardiogram associated with ventricular fibrillation has been of interest to researchers for some time. Over the last few decades, techniques have been developed to analyse this signal in an attempt to obtain more information about the state of the myocardium and the chances of successful defibrillation. This review looks at the implications of analysing the VF waveform and discusses the various techniques that have been used, including fast Fourier transform analysis, wavelet transform analysis and mathematical techniques such as chaos theory.

  9. Ablative therapy for ventricular arrhythmias.

    PubMed

    Klein, L S; Miles, W M

    1995-01-01

    Radiofrequency catheter ablation techniques have enjoyed successful applications in patients with a wide variety of supraventricular tachycardias, especially the Wolff-Parkinson-White syndrome and atrioventricular nodal reentry. More recent reports have shown successful applications in patients with atrial tachycardias and atrial flutter. In addition to these, there are now reports of success during attempts to use radiofrequency techniques to eliminate ventricular tachycardia (VT), both in patients without structural heart disease (idiopathic VT) and patients with structural heart disease (primarily coronary artery disease). Techniques to map sites for ablation in patients with idiopathic VT usually include identifying early endocardial activation and using pace mapping. Success rates for ablation of idiopathic VT have been very high (over 90%) in patients with VT arising from the right ventricular outflow tract. Success rates have not been quite as high when VTs arising from sites other than the right ventricular outflow tract are targeted in the patient with idiopathic VT. In patients with VT caused by coronary artery disease, early endocardial activation and pace mapping can be unreliable. In these patients, searching for mid-diastolic potentials or showing concealed entrainment have proved more reliable. When these latter techniques are applied, success rates in eliminating a single focus of VT in a patient with coronary artery disease has been reported to be as high as 60% to 80%. Future therapies will include new energy sources, new (larger and/or cooled) electrodes, and multipoint catheter mapping, possibly using body surface mapping techniques.

  10. Premature ventricular contractions associated with isotretinoin use*

    PubMed Central

    Alan, Sevil; Ünal, Betül; Yildirim, Aytül

    2016-01-01

    Isotretinoin has been considered a unique drug for acne treatment. However, it is associated with numerous adverse effects. Isotretinoin can trigger premature ventricular contractions. This report describes a 33-year-old-woman who presented with palpitations for 1 week while undergoing 1-month isotretinoin treatment for mild-moderate facial acne. An electrocardiogram and Holter monitoring showed premature ventricular contractions during isotretinoin (Roaccutane, Roche) treatment. Isotretinoin-related premature ventricular contractions were strongly suggested in this case due to the existence of documented premature ventricular contractions on electrocardiograms and the disappearance of these premature ventricular contractions two weeks after termination of the treatment To the authors' knowledge, there has been 1 reported case of premature ventricular contractions linked to isotretinoin use; this report describes a second such case. PMID:28099609

  11. Symptomatic repetitive right ventricular outflow tract ventricular tachycardia in pregnancy and postpartum.

    PubMed

    Goli, Anil K; Koduri, Madhav; Downs, Christopher; Mackall, Judith

    2009-01-01

    Idiopathic ventricular tachycardias, which occur in patients without structural heart disease, are a common entity, representing up to 10% of all ventricular tachycardias evaluated by cardiac electrophysiology services. Pregnancy can increase the incidence of various cardiac arrhythmias. Factors that can potentially promote arrhythmias in pregnancy include the effects of hormones, changes in autonomic tone, hemodynamic perturbations, hypokalemia, and underlying heart disease. Ventricular arrhythmias in pregnancy are repetitive monomorphic ventricular premature complexes and couplets that frequently originate at the right ventricular outflow tract. New onset symptomatic repetitive right ventricular outflow tract ventricular tachycardia during pregnancy has been inadequately reported in the literature. We present a case of symptomatic repetitive right ventricular outflow tract tachycardia that started during pregnancy and continued in the postpartum period, requiring curative treatment with electrophysiology study and radiofrequency ablation.

  12. Heart Disease and Left Ventricular Rotation – A Systematic Review and Quantitative Summary

    PubMed Central

    2012-01-01

    Background Left ventricular (LV) rotation is increasingly examined in those with heart disease. The available evidence measuring LV rotation in those with heart diseases has not been systematically reviewed. Methods To review systematically the evidence measuring LV rotational changes in various heart diseases compared to healthy controls, literature searches were conducted for appropriate articles using several electronic databases (e.g., MEDLINE, EMBASE). All randomized-controlled trials, prospective cohort and case–controlled studies that assessed LV rotation in relation to various heart conditions were included. Three independent reviewers evaluated each investigation’s quality using validated scales. Results were tabulated and levels of evidence assigned. Results A total of 1,782 studies were found through the systematic literature search. Upon review of the articles, 47 were included. The articles were separated into those investigating changes in LV rotation in participants with: aortic stenosis, myocardial infarction, hypertrophic cardiomyopathy, dilated cardiomyopathy, non-compaction, restrictive cardiomyopathy/ constrictive pericarditis, heart failure, diastolic dysfunction, heart transplant, implanted pacemaker, coronary artery disease and cardiovascular disease risk factors. Evidence showing changes in LV rotation due to various types of heart disease was supported by evidence with limited to moderate methodological quality. Conclusions Despite a relatively low quality and volume of evidence, the literature consistently shows that heart disease leads to marked changes in LV rotation, while rotational systolic-diastolic coupling is preserved. No prognostic information exists on the potential value of rotational measures of LV function. The literature suggests that measures of LV rotation may aid in diagnosing subclinical aortic stenosis and diastolic dysfunction. PMID:22726250

  13. Case report: nonarrhythmogenic right ventricular dysplasia presenting with severe right ventricular failure in an adolescent.

    PubMed

    Pac, Mustafa; Pac, Aysenur; Polat, Tugcin Bora; Balli, Sevket; Turhan, Nesrin; Aras, Dursun; Oflaz, Mehmet Burhan; Kücüker, Seref

    2010-02-01

    Right ventricular dysplasia is usually discovered by the presence of ventricular arrhythmia. As arrhythmia is an epiphenomenon, the first presentation of some cases can be primarily heart failure. We describe an adolescent girl who presented with progressive right heart failure and whose hallmark was fibrofatty replacement of ventricular muscle, especially of the right side, without ventricular arrhythmia. The patient was successfully treated by orthotopic heart transplantation.

  14. Catheter Ablation of Ventricular Arrhythmias Arising from the Left Ventricular Summit.

    PubMed

    Santangeli, Pasquale; Lin, David; Marchlinski, Francis E

    2016-03-01

    The left ventricular summit is a common site of origin of idiopathic ventricular arrhythmias. These arrhythmias are most commonly ablated within the coronary venous system or from other adjacent structures, such as the right ventricular and left ventricular outflow tract or coronary cusp region. When ablation from adjacent structures fails, a percutaneous epicardial approach can be considered, but is rarely successful in eliminating the arrhythmias due to proximity to major coronary vessels and/or epicardial fat.

  15. Long-term efficacy of oral encainide in frequent and repetitive ventricular arrhythmias.

    PubMed

    Bongiorni, M G; Levorato, D; Arlotta, C; Paperini, L; Contini, C

    1988-07-01

    The short- and long-term efficacy of oral encainide was studied in 14 patients with chronic high-frequency ventricular arrhythmias and in 14 patients with chronic frequent episodes of non-sustained ventricular tachycardia (NSVT). Encainide efficacy was assessed during a dose-titration period and in a 36-month follow-up also studying the drug effects on routine haematologic data and left ventricular function (LVF). During dose-titration, encainide caused a 78.3% decrease in the average hourly frequency of isolated PVC and a 96.1% reduction in NSVT episodes in the two groups of patients. On follow-up (11 patients in each group) the mean percentage reductions were 95.1% in isolated PVC and 99.7% in NSVT episodes. Encainide did not impair LVF as showed by the comparison of echocardiographic fractional shortening before and after 12 months of treatment. Minor adverse effects of encainide were dose-related visual disturbances in two patients. A major adverse effect was the appearance of sustained VT in one NYHA class IV patient. Oral encainide effectively reduces the frequency of PVC and NSVT, it does not impair left ventricular function and it is associated with infrequent minor side effects. Uncommon, but severe, side effects may appear in patients with marked impairment of left ventricular function.

  16. Electrophysiological studies of the interaction between ventricular myocardium and coronary artery in monkeys.

    PubMed Central

    Mekata, F

    1994-01-01

    1. The electrical influence of the coronary arteries on ventricular muscle was investigated using strips of ventricle that included a section of coronary artery (cardiac preparation) and isolated coronary arteries dissected from the ventricle (arterial preparation). 2. In cardiac preparations, a hyperpolarizing response was recorded from the epicardial surface of the ventricular muscle when acetylcholine (ACh) was added to the organ bath, on condition that the internal diameter of the coronary artery was between 0.15 and 0.6 mm, that the vessel ran at a depth of 0.2 mm or less below the surface of the preparation, and that the recording microelectrode was immediately adjacent to the artery. 3. ACh-induced hyperpolarization was not detected in cardiac preparations which had no detectable arteries, or at sites distant from visible arteries. 4. In arterial preparations, a similar hyperpolarizing response was evoked by ACh in all vessels with an i.d. of 0.15-1.2 mm. 5. In a preparation combining ventricular muscle and a strip of coronary artery (with the vascular endothelium in direct contact with the epicardial surface of the ventricular myocardium), hyperpolarization was also observed from the ventricular muscle after application of ACh. 6. The hyperpolarizing response of the ventricular myocardium in the cardiac preparation and in combined preparations of ventricular muscle and coronary artery was weakened or abolished by removal of the arterial endothelium. 7. These results indicate that some substance released from the coronary arterial endothelium after stimulation by ACh induces hyperpolarization of the ventricular myocardium. PMID:7869248

  17. Differences between outward currents of human atrial and subepicardial ventricular myocytes.

    PubMed Central

    Amos, G J; Wettwer, E; Metzger, F; Li, Q; Himmel, H M; Ravens, U

    1996-01-01

    1. Outward currents were studied in myocytes isolated from human atrial and subepicardial ventricular myocardium using the whole-cell voltage clamp technique at 22 degrees C. The Na+ current was inactivated with prepulses to -40 mV and the Ca2+ current was eliminated by both reducing extracellular [Ca2+] to 0.5 mM and addition of 100 microM CdCl2 to the bath solution. 2. In human myocytes, three different outward currents were observed. A slowly inactivating sustained outward current, I(so), was found in atrial but not ventricular myocytes. A rapidly inactivating outward current, I(to), of similar current density was observed in cells from the two tissues. An additional uncharacterized non-inactivating background current of similar size was observed in atrial and in ventricular myocytes. 3. I(to) and I(so) could be differentiated in atrial myocytes by their different kinetics and potential dependence of inactivation, and their different sensitivities to block by 4-amino-pyridine, suggesting that two individual channel types were involved. 4. In atrial cells, inactivation of I(to) was more rapid and steady-state inactivation occurred at more negative membrane potentials than in ventricular cells. Furthermore, the recovery of I(to) from inactivation was slower and without overshoot in atrial myocytes. In addition, 4-aminopyridine-induced block of I(to) was more efficient in atrial than in ventricular cells. These observations suggest that the channels responsible for atrial and ventricular I(to) were not identical. 5. We conclude that the differences in outward currents substantially contribute to the particular shapes of human atrial and ventricular action potentials. The existence of I(so) in atrial cells only provides a clinically interesting target for anti-arrhythmic drug action, since blockers of I(so) would selectively prolong the atrial refractory period, leaving ventricular refractoriness unaltered. PMID:9011620

  18. Bundle Branch Reentrant Ventricular Tachycardia

    PubMed Central

    Mazur, Alexander; Kusniec, Jairo; Strasberg, Boris

    2005-01-01

    Bundle branch reentrant (BBR) tachycardia is an uncommon form of ventricular tachycardia (VT) incorporating both bundle branches into the reentry circuit. The arrhythmia is usually seen in patients with an acquired heart disease and significant conduction system impairment, although patients with structurally normal heart have been described. Surface ECG in sinus rhythm (SR) characteristically shows intraventricular conduction defects. Patients typically present with presyncope, syncope or sudden death because of VT with fast rates frequently above 200 beats per minute. The QRS morphology during VT is a typical bundle branch block pattern, usually left bundle branch block, and may be identical to that in SR. Prolonged His-ventricular (H-V) interval in SR is found in the majority of patients with BBR VT, although some patients may have the H-V interval within normal limits. The diagnosis of BBR VT is based on electrophysiological findings and pacing maneuvers that prove participation of the His- Purkinje system in the tachycardia mechanism. Radiofrequency catheter ablation of a bundle branch can cure BBR VT and is currently regarded as the first line therapy. The technique of choice is ablation of the right bundle. The reported incidence of clinically significant conduction system impairment requiring implantation of a permanent pacemaker varies from 0% to 30%. Long-term outcome depends on the underlying cardiac disease. Patients with poor systolic left ventricular function are at risk of sudden death or death from progressive heart failure despite successful BBR VT ablation and should be considered for an implantable cardiovertor-defibrillator. PMID:16943949

  19. Right ventricular failure after left ventricular assist devices.

    PubMed

    Lampert, Brent C; Teuteberg, Jeffrey J

    2015-09-01

    Most patients with advanced systolic dysfunction who are assessed for a left ventricular assist device (LVAD) also have some degree of right ventricular (RV) dysfunction. Hence, RV failure (RVF) remains a common complication of LVAD placement. Severe RVF after LVAD implantation is associated with increased peri-operative mortality and length of stay and can lead to coagulopathy, altered drug metabolism, worsening nutritional status, diuretic resistance, and poor quality of life. However, current medical and surgical treatment options for RVF are limited and often result in significant impairments in quality of life. There has been continuing interest in developing risk models for RVF before LVAD implantation. This report reviews the anatomy and physiology of the RV and how it changes in the setting of LVAD support. We will discuss proposed mechanisms and describe biochemical, echocardiographic, and hemodynamic predictors of RVF in LVAD patients. We will describe management strategies for reducing and managing RVF. Finally, we will discuss the increasingly recognized and difficult to manage entity of chronic RVF after LVAD placement and describe opportunities for future research. Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  20. Epicardial Ablation For Ventricular Tachycardia

    PubMed Central

    Maccabelli, Giuseppe; Mizuno, Hiroya; Della Bella, Paolo

    2012-01-01

    Epicardial ablation has lately become a necessary tool to approach some ventricular tachycardias in different types of cardiomyopathy. Its diffusion is now limited to a few high volume centers not because of the difficulty of the pericardial puncture but since it requires high competence not only in the VT ablation field but also in knowing and recognizing the possible complications each of which require a careful treatment. This article will review the state of the art of epicardial ablation with special attention to the procedural aspects and to the possible selection criteria of the patients PMID:23233758

  1. FGF23 induces left ventricular hypertrophy

    PubMed Central

    Faul, Christian; Amaral, Ansel P.; Oskouei, Behzad; Hu, Ming-Chang; Sloan, Alexis; Isakova, Tamara; Gutiérrez, Orlando M.; Aguillon-Prada, Robier; Lincoln, Joy; Hare, Joshua M.; Mundel, Peter; Morales, Azorides; Scialla, Julia; Fischer, Michael; Soliman, Elsayed Z.; Chen, Jing; Go, Alan S.; Rosas, Sylvia E.; Nessel, Lisa; Townsend, Raymond R.; Feldman, Harold I.; St. John Sutton, Martin; Ojo, Akinlolu; Gadegbeku, Crystal; Di Marco, Giovana Seno; Reuter, Stefan; Kentrup, Dominik; Tiemann, Klaus; Brand, Marcus; Hill, Joseph A.; Moe, Orson W.; Kuro-o, Makoto; Kusek, John W.; Keane, Martin G.; Wolf, Myles

    2011-01-01

    Chronic kidney disease (CKD) is a public health epidemic that increases risk of death due to cardiovascular disease. Left ventricular hypertrophy (LVH) is an important mechanism of cardiovascular disease in individuals with CKD. Elevated levels of FGF23 have been linked to greater risks of LVH and mortality in patients with CKD, but whether these risks represent causal effects of FGF23 is unknown. Here, we report that elevated FGF23 levels are independently associated with LVH in a large, racially diverse CKD cohort. FGF23 caused pathological hypertrophy of isolated rat cardiomyocytes via FGF receptor–dependent activation of the calcineurin-NFAT signaling pathway, but this effect was independent of klotho, the coreceptor for FGF23 in the kidney and parathyroid glands. Intramyocardial or intravenous injection of FGF23 in wild-type mice resulted in LVH, and klotho-deficient mice demonstrated elevated FGF23 levels and LVH. In an established animal model of CKD, treatment with an FGF–receptor blocker attenuated LVH, although no change in blood pressure was observed. These results unveil a klotho-independent, causal role for FGF23 in the pathogenesis of LVH and suggest that chronically elevated FGF23 levels contribute directly to high rates of LVH and mortality in individuals with CKD. PMID:21985788

  2. Increased susceptibility of spontaneously hypertensive rats to ventricular tachyarrhythmias in early hypertension

    PubMed Central

    Sovari, Ali A.; Pezhouman, Arash; Iyer, Shankar; Cao, Hong; Ko, Christopher Y.; Bapat, Aneesh; Vahdani, Nooshin; Ghanim, Mostafa; Fishbein, Michael C.

    2016-01-01

    Key points Hypertension is a risk factor for sudden cardiac death caused by ventricular tachycardia and fibrillation.Whether hypertension in its early stage is associated with an increased risk of ventricular tachyarrhythmias is not known.Based on experiments performed at the cellular and whole heart levels, we show that, even early in chronic hypertension, the hypertrophied and fibrotic ventricles of spontaneously hypertensive rats aged 5 to 6 months have already developed increased stress‐induced arrhythmogenicity, and this increased susceptibility to ventricular arrhythmias is primarily a result of tissue remodelling rather than cellular electrophysiological changes.Our findings highlight the need for early hypertension treatment to minimize myocardial fibrosis, ventricular hypertrophy, and arrhythmias. Abstract Hypertension is a risk factor for sudden cardiac death caused by ventricular tachycardia and fibrillation (VT/VF). We hypothesized that, in early hypertension, the susceptibility to stress‐induced VT/VF increases. We compared the susceptibility of 5‐ to 6‐month‐old male spontaneously hypertensive rats (SHR) and age/sex‐matched normotensive rats (NR) to VT/VF during challenge with oxidative stress (H2O2; 0.15 mmol l−1). We found that only SHR hearts exhibited left ventricular fibrosis and hypertrophy. H2O2 promoted VT in all 30 SHR but none of the NR hearts. In 33% of SHR cases, focal VT degenerated to VF within 3 s. Simultaneous voltage‐calcium optical mapping of Langendorff‐perfused SHR hearts revealed that H2O2‐induced VT/VF arose spontaneously from focal activations at the base and mid left ventricular epicardium. Microelectrode recording of SHR hearts showed that VT was initiated by early afterdepolarization (EAD)‐mediated triggered activity. However, despite the increased susceptibility of SHR hearts to VT/VF, patch clamped isolated SHR ventricular myocytes developed EADs and triggered activity to the same extent as NR

  3. Bidirectional ventricular tachycardia of unusual etiology

    PubMed Central

    Chakraborty, Praloy; Kaul, Bhavna; Mandal, Kausik; Isser, H.S.; Bansal, Sandeep; Subramanian, Anandaraja

    2016-01-01

    Bidirectional ventricular tachycardia (BDVT) is a rare form of ventricular arrhythmia, characterized by changing QRS axis of 180 degrees. Digitalis toxicity is considered as commonest cause of BDVT; other causes include aconite toxicity, myocarditis, myocardial infarction, metastatic cardiac tumour and cardiac channelopathies. We describe a case of BDVT in a patient with Anderson-Tawil syndrome. PMID:27479206

  4. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration or...

  5. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration or...

  6. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration or...

  7. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration or...

  8. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration or...

  9. An Unconventional Route of Left Ventricular Pacing

    PubMed Central

    Sinha, Santosh Kumar; Varm, Chandra Mohan; Thakur, Ramesh; Krishna, Vinay; Goel, Amit; Kumar, Ashutosh; Jha, Mukesh Jitendra; Mishra, Vikas; Singh Syal, Karandeep

    2015-01-01

    We present a case of a rare complication of transvenous right ventricular pacing by temporary pacing wire causing iatrogenic interventricular septal perforation and left ventricular pacing in a 69-year-old man who was referred for recurrent syncope with sinus arrest. PMID:28197251

  10. Ventricular-Fold Dynamics in Human Phonation

    ERIC Educational Resources Information Center

    Bailly, Lucie; Bernardoni, Nathalie Henrich; Müller, Frank; Rohlfs, Anna-Katharina; Hess, Markus

    2014-01-01

    Purpose: In this study, the authors aimed (a) to provide a classification of the ventricular-fold dynamics during voicing, (b) to study the aerodynamic impact of these motions on vocal-fold vibrations, and (c) to assess whether ventricular-fold oscillations could be sustained by aerodynamic coupling with the vocal folds. Method: A 72-sample…

  11. Ventricular-Fold Dynamics in Human Phonation

    ERIC Educational Resources Information Center

    Bailly, Lucie; Bernardoni, Nathalie Henrich; Müller, Frank; Rohlfs, Anna-Katharina; Hess, Markus

    2014-01-01

    Purpose: In this study, the authors aimed (a) to provide a classification of the ventricular-fold dynamics during voicing, (b) to study the aerodynamic impact of these motions on vocal-fold vibrations, and (c) to assess whether ventricular-fold oscillations could be sustained by aerodynamic coupling with the vocal folds. Method: A 72-sample…

  12. Ventricular fibrillation coinciding with phentermine initiation.

    PubMed

    Tobbia, Patrick; Norris, Leslie A; Klima, Lawrence D

    2012-10-12

    A 70-year-old woman developed ventricular fibrillation subsequent to initiation of phentermine therapy. She was hospitalised and experienced recurrent ventricular fibrillation. During cardiac catheterisation, she was found to have a right coronary artery vasospasm, which resolved with intravenous nitroglycerin. Her phentermine was discontinued and the patient remained symptom free at last follow-up.

  13. [Left ventricular function in pulmonary arterial hypertension].

    PubMed

    Khomaziuk, V A

    1998-12-01

    Echocardiographic evaluation was done of left ventricular functional state in 90 patients with primary and secondary pulmonary arterial hypertension with and without intercavitary shunting. Changes in left ventricular function were identified in 86% cases; they reflected disturbances in both ventricles compensatory interaction. The degree of changes depended on the degree of dilatation of the right ventricle and level of interchamber shunting.

  14. Giant and thrombosed left ventricular aneurysm.

    PubMed

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-07-26

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  15. Dissimilar ventricular rhythms: implications for ICD therapy.

    PubMed

    Barold, S Serge; Kucher, Andreas; Nägele, Herbert; Buenfil Medina, José Carlos; Brodsky, Michael; Van Heuverswyn, Frederic E; Stroobandt, Roland X

    2013-04-01

    Sensing of left ventricular (LV) activity in some devices used for cardiac resynchronization therapy (CRT) was designed primarily to prevent the delivery of an LV stimulus into the LV vulnerable period. Such a sensing function of the LV channel is not universally available in contemporary CRT devices. Recordings of LV electrograms may provide special diagnostic data unavailable solely from the standard right ventricular electrogram and corresponding marker channel. We used the LV sensing function of Biotronik CRT defibrillators to find 3 cases of dissimilar ventricular rhythms or tachyarrhythmias. Such arrhythmias are potentially important because concomitant slower right ventricular activity may prevent or delay implantable cardioverter-defibrillator therapy for a life-threatening situation involving a faster and more serious LV tachyarrhythmia. Dissimilar ventricular rhythms may not be rare and may account for cases of unexplained sudden death with a normally functioning implantable cardioverter-defibrillator and no recorded terminal arrhythmia.

  16. Arrhythmogenic right ventricular cardiomyopathy in two cats.

    PubMed

    Harvey, A M; Battersby, I A; Faena, M; Fews, D; Darke, P G G; Ferasin, L

    2005-03-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disease characterised by infiltration of the myocardium by adipose and fibrous tissue. The disease is an important cause of sudden death in humans, but has rarely been described in animals. This report describes ARVC in two cats with right-sided congestive heart failure. One cat had also experienced previous episodes of syncope. Standard six-lead and 24-hour (Holter) electrocardiogram recording revealed complete atrioventricular block and multiform ventricular ectopics in both cats, with the addition of ventricular tachycardia, ventricular bigeminy and R-on-T phenomenon in one of them. On echocardiography, the right ventricle and atrium were massively dilated and hypokinetic. The survival times of the cats were three days and 16 days following diagnosis. Histopathology in one case revealed fibro-fatty infiltration of the myocardium, predominantly affecting the right ventricular free wall.

  17. Giant and thrombosed left ventricular aneurysm

    PubMed Central

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-01-01

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention. PMID:26225205

  18. Arrhythmogenic right ventricular cardiomyopathy/dysplasia mimicking rape homicide: a case report.

    PubMed

    Racette, Stéphanie; Sauvageau, Anny

    2005-10-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC), also known as arrhythmogenic right ventricular dysplasia, is a known cause of sudden unexplained death in young, otherwise healthy adults. In the forensic setting, several cases of fatal ARVC have been reported, mostly occurring during physical exercise. However, a very few cases present where the death scene is mistaken for a homicide. We report here the case of a 23-year-old woman, found dead, lying in the snow on an isolated property. The woman's genitals were exposed, with her trousers down over her thighs. Rape homicide was strongly suspected, but autopsy findings proved otherwise.

  19. Pure right ventricular infarction resulting from coronary ectasia: importance of diagnostic imaging.

    PubMed

    Palfy, Julia A; Tomás, Marta; Farré, Jerónimo; Navas, Miguel A; Navarro, Felipe; Orejas, Miguel; Franco, Angeles

    2014-04-01

    Isolated right ventricular (RV) infarction may occur during percutaneous coronary intervention resulting from selective occlusion of a ventricular branch of the right coronary artery (RCA). We present a case of a pure RV infarction without iatrogenic origin that at the initial electrocardiographic analysis was suggestive of a left anterior descending artery-related acute myocardial infarction. Coronary angiography results made us suspect thrombotic occlusion of a small branch of the ectatic RCA resulting from slow flow. Final diagnosis was confirmed by coronary computed tomographic angiography and cardiac magnetic resonance imaging, underlining the essential diagnostic role of these imaging modalities. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  20. His bundle activates faster than ventricular myocardium during prolonged ventricular fibrillation.

    PubMed

    Angel, Nathan; Li, Li; Dosdall, Derek J

    2014-01-01

    The Purkinje fiber system has recently been implicated as an important driver of the rapid activation rate during long duration ventricular fibrillation (VF>2 minutes). The goal of this study is to determine whether this activity propagates to or occurs in the proximal specialized conduction system during VF as well. An 8×8 array with 300 µm spaced electrodes was placed over the His bundles of isolated, perfused rabbit hearts (n = 12). Ventricular myocardial (VM) and His activations were differentiated by calculating Laplacian recordings from unipolar signals. Activation rates of the VM and His bundle were compared and the His bundle conduction velocity was measured during perfused VF followed by 8 minutes of unperfused VF. During perfused VF the average VM activation rate of 11.04 activations/sec was significantly higher than the His bundle activation rate of 6.88 activations/sec (p<0.05). However from 3-8 minutes of unperfused VF the His system activation rate (6.16, 5.53, 5.14, 5.22, 6.00, and 4.62 activations/sec significantly faster than the rate of the VM (4.67, 3.63, 2.94, 2.24, 3.45, and 2.31 activations/sec) (p<0.05). The conduction velocity of the His system immediately decreased to 94% of the sinus rate during perfused VF then gradually decreased to 67% of sinus rhythm conduction at 8 minutes of unperfused VF. During prolonged VF the activation rate of the His bundle is faster than that of the VM. This suggests that the proximal conduction system, like the distal Purkinje system, may be an important driver during long duration VF and may be a target for interventional therapy.

  1. Brain Emboli After Left Ventricular Endocardial Ablation.

    PubMed

    Whitman, Isaac R; Gladstone, Rachel A; Badhwar, Nitish; Hsia, Henry H; Lee, Byron K; Josephson, S Andrew; Meisel, Karl M; Dillon, William P; Hess, Christopher P; Gerstenfeld, Edward P; Marcus, Gregory M

    2017-02-28

    Catheter ablation for ventricular tachycardia and premature ventricular complexes (PVCs) is common. Catheter ablation of atrial fibrillation is associated with a risk of cerebral emboli attributed to cardioversions and numerous ablation lesions in the low-flow left atrium, but cerebral embolic risk in ventricular ablation has not been evaluated. We enrolled 18 consecutive patients meeting study criteria scheduled for ventricular tachycardia or PVC ablation over a 9-month period. Patients undergoing left ventricular (LV) ablation were compared with a control group of those undergoing right ventricular ablation only. Patients were excluded if they had implantable cardioverter defibrillators or permanent pacemakers. Radiofrequency energy was used for ablation in all cases and heparin was administered with goal-activated clotting times of 300 to 400 seconds for all LV procedures. Pre- and postprocedural brain MRI was performed on each patient within a week of the ablation procedure. Embolic infarcts were defined as new foci of reduced diffusion and high signal intensity on fluid-attenuated inversion recovery brain MRI within a vascular distribution. The mean age was 58 years, half of the patients were men, half had a history of hypertension, and the majority had no known vascular disease or heart failure. LV ablation was performed in 12 patients (ventricular tachycardia, n=2; PVC, n=10) and right ventricular ablation was performed exclusively in 6 patients (ventricular tachycardia, n=1; PVC, n=5). Seven patients (58%) undergoing LV ablation experienced a total of 16 cerebral emboli, in comparison with zero patients undergoing right ventricular ablation (P=0.04). Seven of 11 patients (63%) undergoing a retrograde approach to the LV developed at least 1 new brain lesion. More than half of patients undergoing routine LV ablation procedures (predominately PVC ablations) experienced new brain emboli after the procedure. Future research is critical to understanding the long

  2. Acidosis slows electrical conduction through the atrio-ventricular node

    PubMed Central

    Nisbet, Ashley M.; Burton, Francis L.; Walker, Nicola L.; Craig, Margaret A.; Cheng, Hongwei; Hancox, Jules C.; Orchard, Clive H.; Smith, Godfrey L.

    2014-01-01

    Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN). In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode's solution (20% CO2, pH 6.7) increased the time of earliest activation (Tact) from 100.5 ± 7.9 to 166.1 ± 7.2 ms (n = 8) at a pacing cycle length (PCL) of 300 ms (37°C). Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150 ms PCL, Tact was prolonged from 131.0 ± 5.2 to 174.9 ± 16.3 ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode's solutions at pH 7.4 (control), 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH) interval, the AVN effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis. PMID:25009505

  3. Acidosis slows electrical conduction through the atrio-ventricular node.

    PubMed

    Nisbet, Ashley M; Burton, Francis L; Walker, Nicola L; Craig, Margaret A; Cheng, Hongwei; Hancox, Jules C; Orchard, Clive H; Smith, Godfrey L

    2014-01-01

    Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN). In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode's solution (20% CO2, pH 6.7) increased the time of earliest activation (Tact) from 100.5 ± 7.9 to 166.1 ± 7.2 ms (n = 8) at a pacing cycle length (PCL) of 300 ms (37°C). Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150 ms PCL, Tact was prolonged from 131.0 ± 5.2 to 174.9 ± 16.3 ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode's solutions at pH 7.4 (control), 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH) interval, the AVN effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis.

  4. Comparison of Left Ventricular Electromechanical Mapping and Left Ventricular Angiography

    PubMed Central

    Sarmento-Leite, Rogerio; Silva, Guilherme V.; Dohman, Hans F.R.; Rocha, Ricardo Mourilhe; Dohman, Hans J.F.; de Mattos, Nelson Durval S.G.; Carvalho, Luis Antonio; Gottschall, Carlos A.M.; Perin, Emerson C.

    2003-01-01

    We performed this prospective cohort study to correlate the findings of left ventricular angiography (LVA) and NOGA™ left ventricular electromechanical mapping (LVEM) in the evaluation of cardiac wall motion and also to establish standards for wall motion assessment by LVEM. Fifty-five patients (35 men; mean age, 60.4 ± 11.8 years) eligible for elective left cardiac catheterization underwent LVA and LVEM. Wall motion scores, LV ejection fractions (LVEF), and LV volumes derived from LVA versus LVEM data were compared and analyzed statistically. Receiver operating characteristic (ROC) curves were used to assess the accuracy of LVEM in distinguishing between normal, hypokinetic, and akinetic/dyskinetic wall motion. Mean LVEM procedure time was 37 ± 11 minutes. The LVEM and LVA findings differed for mean LVEF (55% ± 13% vs 36% ± 9%), mean end-systolic volume (56 ± 13 mL vs 36 ± 10 mL), and mean end-diastolic volume (174 ± 104 mL vs 123 ± 65 mL). Mean wall motion scores (± SD) for normokinetic, hypokinetic, and akinetic/dyskinetic segments were 13.9% ± 5.6%, 8.3% ± 5.2%, and 3.2% ± 3.1%, respectively. Cutpoints for differentiating between wall motion types were 12% and 6%. The ROC curves showed LVEM to have a 93% accuracy in differentiating between normokinetic and akinetic/dyskinetic segments and a 73% accuracy between normokinetic and hypokinetic segments. These data suggest that LVEM can differentiate between normal and abnormal cardiac wall motion, although it is more accurate at differentiating between normokinetic and akinetic/dyskinetic motion than between normokinetic and hypokinetic motion. (Tex Heart Inst J 2003;30:19–26) PMID:12638666

  5. [Mechanism of induction and termination of ventricular fibrillation--significance of dispersion of ventricular repolarization].

    PubMed

    Behrens, S; Zabel, M; Franz, M R; Schultheiss, H P

    2000-12-01

    It has been known for many years that ventricular fibrillation may be induced and terminated by electrical field stimuli. Recent experimental studies have shown that both fibrillation and defibrillation have a common electrophysiologic mechanism that is based on the interaction between the electrical field stimulus and ventricular repolarization. Ventricular fibrillation will be induced if the field stimulus is applied with the area of vulnerability, this area of vulnerability is defined two dimensionally by the shock coupling interval and shock strength, and is modified by the configuration of the shock. A field shock that is applied within the area of vulnerability causes heterogeneity of ventricular repolarization immediately after the shock (postshock dispersion), thereby enabling the development of circuit movements and reentry, and resulting in ventricular fibrillation. High energy shocks, however, that are applied above the area of vulnerability (i.e., above the upper limit of vulnerability) will not induce ventricular fibrillation due to homogeneous prolongation of repolarization and a resulting small postshock dispersion. In analogy, ventricular fibrillation will continue after unsuccessful low-energy defibrillation shocks due to high postshock dispersion, whereas a high-energy shock will synchronize ventricular repolarization, thereby causing small postshock dispersion and termination of ventricular fibrillation. This paper describes the relation between fibrillation, defibrillation and ventricular repolarization based on experimental findings. A possible clinical application of these findings is that the upper limit of vulnerability may be used as a surrogate for the defibrillation threshold. Thus, defibrillation threshold testing may not be necessary during future implantations of automatic cardioverter defibrillators.

  6. Effects of a left ventricular assist device with a centrifugal pump on left ventricular diastolic hemodynamics.

    PubMed

    Saito, Akira

    2002-10-01

    The purpose of this investigation was to analyze how left ventricular assist device (LVAD) with a centrifugal pump alters left ventricular diastolic hemodynamics and energy by means of a left ventricular pressure volume relationship. Fifteen anesthetized normal pig hearts were studied after placement of an apical drainage LVAD with a centrifugal pump. Indices of the left ventricular isovolumic relaxation phase, left ventricular filling phase and general hemodynamic data were recorded with the LVAD in on and off situations. The pump assist rate was adjusted to 25%, 50% and 75%. Left ventricular stroke work, with a high correlation with oxygen consumption, decreased as the assist rate increased. Left ventricular relaxation delayed as the assist rate increased, but the atrioventricular pressure gradient increased in the left ventricular rapid filling phase. This finding clarifies left ventricular rapid filling. In this study, it was suggested that although left ventricular isovolumic relaxation was affected, 75% assistance is the most effective for the pump flow in terms of circulation support and restoration of cardiac function.

  7. Renal denervation suppresses ventricular arrhythmias during acute ventricular ischemia in pigs.

    PubMed

    Linz, Dominik; Wirth, Klaus; Ukena, Christian; Mahfoud, Felix; Pöss, Janine; Linz, Benedikt; Böhm, Michael; Neuberger, Hans-Ruprecht

    2013-10-01

    Increased sympathetic activation during acute ventricular ischemia is involved in the occurrence of life-threatening arrhythmias. To test the effect of sympathetic inhibition by renal denervation (RDN) on ventricular ischemia/reperfusion arrhythmias. Anesthetized pigs, randomized to RDN or SHAM treatment, were subjected to 20 minutes of left anterior descending coronary artery (LAD) occlusion followed by reperfusion. Infarct size, hemodynamics, premature ventricular contractions, and spontaneous ventricular tachyarrhythmias were analyzed. Monophasic action potentials were recorded with an epicardial probe at the ischemic area. Ventricular ischemia resulted in an acute reduction of blood pressure (-29%) and peak left ventricular pressure rise (-40%), which were not significantly affected by RDN. However, elevation of left ventricular end-diastolic pressure (LVEDP) during LAD ligation was attenuated by RDN (ΔLVEDP: +1.8 ± 0.6 mm Hg vs +9.7 ± 1 mm Hg in the SHAM group; P = .046). Infarct size was not affected by RDN compared to SHAM. RDN significantly reduced spontaneous ventricular extrabeats (160 ± 15/10 min in the RDN group vs 422 ± 36/10 min in the SHAM group; P = .021) without affecting coupling intervals. In 5 of 6 SHAM-treated animals, ventricular fibrillation (VF) occurred during LAD occlusion. By contrast, only 1 of 7 RDN-treated animals experienced VF (P = .029). Beta-receptor blockade by atenolol showed comparable effects. Neither VF nor transient shortening of monophasic action potential duration during reperfusion was inhibited by RDN. RDN reduced the occurrence of ventricular arrhythmias/fibrillation and attenuated the rise in LVEDP during left ventricular ischemia without affecting infarct size, changes in ventricular contractility, blood pressure, and reperfusion arrhythmias. Therefore, RDN may protect from ventricular arrhythmias during ischemic events. © 2013 Heart Rhythm Society. All rights reserved.

  8. Electrohydraulic ventricular assist device development.

    PubMed

    Diegel, P D; Mussivand, T; Holfert, J W; Nahon, D; Miller, J; Maclean, G K; Santerre, J P; Bearnson, G B; Juretich, J; Hansen, A C

    1991-01-01

    A 64 ml (effective stroke volume) in vitro electrohydraulic ventricular assist device (VAD) prototype has been built. The energy converter is an axial flow pump driven by a brushless direct current (DC) motor. Systole begins as silicone oil is pumped from the volume displacement chamber (VDC) into the ventricle, displacing the flexing diaphragm separating the oil and the blood. In diastole, the motor reverses, providing active filling by pumping oil from the ventricle into the VDC. The surface mount electronic internal controller provides motor commutator, energy management, telemetry, and physiologic control functions. Energy is supplied externally by either a 12 V DC power supply or a 12 V DC rechargeable battery and is transmitted through the skin by a transcutaneous energy transformer (TET). Energy can also be supplied by a 12 V DC rechargeable internal battery. Bidirectional infrared telemetry is used to transmit information between the internal and external controllers.

  9. Are ventricular assist devices underutilized?

    PubMed

    Boyle, Andrew J

    2010-07-01

    A dramatic shift in the durability and reliability of ventricular assist device (VAD) therapy is taking hold due to the newer generations of continuous flow VADs that are either in clinical trials or under consideration by the Food and Drug Administration (FDA) for commercial approval. To expand the pool of potential mechanical circulatory support (MCS) patients, device reliability will need to prove to be greatly enhanced over previous generations of VADs and functional capacity and quality of life will need to improve substantially over baseline. Improved patient selection should have the simultaneously beneficial effects of improving outcomes while expanding the MCS patient population. The critical factors determining the likelihood of expansion of the MCS field include, but are not limited to, improvements in technology and its reliability, training and education of all advanced heart failure caregivers, improving availability of MCS geographically, and a shift in patient selection to a population more likely to benefit from MCS therapy.

  10. Automated left ventricular capture management.

    PubMed

    Crossley, George H; Mead, Hardwin; Kleckner, Karen; Sheldon, Todd; Davenport, Lynn; Harsch, Manya R; Parikh, Purvee; Ramza, Brian; Fishel, Robert; Bailey, J Russell

    2007-10-01

    The stimulation thresholds of left ventricular (LV) leads tend to be less reliable than conventional leads. Cardiac resynchronization therapy (CRT) requires continuous capture of both ventricles. The purpose of this study is to evaluate a novel algorithm for the automatic measurement of the stimulation threshold of LV leads in cardiac resynchronization systems. We enrolled 134 patients from 18 centers who had existing CRT-D systems. Software capable of automatically executing LV threshold measurements was downloaded into the random access memory (RAM) of the device. The threshold was measured by pacing in the left ventricle and analyzing the interventricular conduction sensed in the right ventricle. Automatic LV threshold measurements were collected and compared with manual LV threshold tests at each follow-up visit and using a Holter monitor system that recorded both the surface electrocardiograph (ECG) and continuous telemetry from the device. The proportion of Left Ventricular Capture Management (LVCM) in-office threshold tests within one programming step of the manual threshold test was 99.7% (306/307) with a two-sided 95% confidence interval of (98.2%, 100.0%). The algorithm measured the threshold successfully in 96% and 97% of patients after 1 and 3 months respectively. Holter monitor analysis in a subset of patients revealed accurate performance of the algorithm. This study demonstrated that the LVCM algorithm is safe, accurate, and highly reliable. LVCM worked with different types of leads and different lead locations. LVCM was demonstrated to be clinically equivalent to the manual LV threshold test. LVCM offers automatic measurement, output adaptation, and trends of the LV threshold and should result in improved ability to maintain LV capture without sacrificing device longevity.

  11. β1-Adrenoceptor blocker aggravated ventricular arrhythmia.

    PubMed

    Wang, Yan; Patel, Dimpi; Wang, Dao Wu; Yan, Jiang Tao; Hsia, Henry H; Liu, Hao; Zhao, Chun Xia; Zuo, Hou Juan; Wang, Dao Wen

    2013-11-01

    To assess the impact of β1 -adrenoceptor blockers (β1 -blocker) and isoprenaline on the incidence of idiopathic repetitive ventricular arrhythmia that apparently decreases with preprocedural anxiety. From January 2010 to July 2012, six patients were identified who had idiopathic ventricular arrhythmias that apparently decreased (by greater than 90%) with preprocedural anxiety. The number of ectopic ventricular beats per hour (VPH) was calculated from Holter or telemetry monitoring to assess the ectopic burden. The mean VPH of 24 hours from Holter before admission (VPH-m) was used as baseline (100%) for normalization. β1 -Blockers, isoprenaline, and/or aminophylline were administrated successively on the ward and catheter lab to evaluate their effects on the ventricular arrhythmias. Among 97 consecutive patients with idiopathic ventricular arrhythmias, six had reduction in normalized VPHs in the hour before the scheduled procedure time from (104.6 ± 4.6%) to (2.8 ± 1.6%) possibly due to preprocedural anxiety (P < 0.05), then increased to (97.9 ± 9.7%) during β1 -blocker administration (P < 0.05), then quickly reduced to (1.6 ± 1.0%) during subsequent isoprenaline infusion. Repeated β1 -blocker quickly counteracted the inhibitory effect of isoprenaline, and VPHs increased to (120.9 ± 2.4%) from (1.6 ± 1.0%; P < 0.05). Isoprenaline and β1 -blocker showed similar effects on the arrhythmias in catheter lab. In some patients with structurally normal heart and ventricular arrhythmias there is a marked reduction of arrhythmias associated with preprocedural anxiety. These patients exhibit a reproducible sequence of β1 -blocker aggravation and catecholamine inhibition of ventricular arrhythmias, including both repetitive ventricular premature beats and monomorphic ventricular tachycardia. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  12. Calcium-activated potassium current modulates ventricular repolarization in chronic heart failure.

    PubMed

    Bonilla, Ingrid M; Long, Victor P; Vargas-Pinto, Pedro; Wright, Patrick; Belevych, Andriy; Lou, Qing; Mowrey, Kent; Yoo, Jae; Binkley, Philip F; Fedorov, Vadim V; Györke, Sandor; Janssen, Paulus M L; Kilic, Ahmet; Mohler, Peter J; Carnes, Cynthia A

    2014-01-01

    The role of I(KCa) in cardiac repolarization remains controversial and varies across species. The relevance of the current as a therapeutic target is therefore undefined. We examined the cellular electrophysiologic effects of I(KCa) blockade in controls, chronic heart failure (HF) and HF with sustained atrial fibrillation. We used perforated patch action potential recordings to maintain intrinsic calcium cycling. The I(KCa) blocker (apamin 100 nM) was used to examine the role of the current in atrial and ventricular myocytes. A canine tachypacing induced model of HF (1 and 4 months, n = 5 per group) was used, and compared to a group of 4 month HF with 6 weeks of superimposed atrial fibrillation (n = 7). A group of age-matched canine controls were used (n = 8). Human atrial and ventricular myocytes were isolated from explanted end-stage failing hearts which were obtained from transplant recipients, and studied in parallel. Atrial myocyte action potentials were unchanged by I(KCa) blockade in all of the groups studied. I(KCa) blockade did not affect ventricular myocyte repolarization in controls. HF caused prolongation of ventricular myocyte action potential repolarization. I(KCa) blockade caused further prolongation of ventricular repolarization in HF and also caused repolarization instability and early afterdepolarizations. SK2 and SK3 expression in the atria and SK3 in the ventricle were increased in canine heart failure. We conclude that during HF, I(KCa) blockade in ventricular myocytes results in cellular arrhythmias. Furthermore, our data suggest an important role for I(KCa) in the maintenance of ventricular repolarization stability during chronic heart failure. Our findings suggest that novel antiarrhythmic therapies should have safety and efficacy evaluated in both atria and ventricles.

  13. Calcium-Activated Potassium Current Modulates Ventricular Repolarization in Chronic Heart Failure

    PubMed Central

    Bonilla, Ingrid M.; Long, Victor P.; Vargas-Pinto, Pedro; Wright, Patrick; Belevych, Andriy; Lou, Qing; Mowrey, Kent; Yoo, Jae; Binkley, Philip F.; Fedorov, Vadim V.; Györke, Sandor; Janssen, Paulus M. L.; Kilic, Ahmet; Mohler, Peter J.; Carnes, Cynthia A.

    2014-01-01

    The role of IKCa in cardiac repolarization remains controversial and varies across species. The relevance of the current as a therapeutic target is therefore undefined. We examined the cellular electrophysiologic effects of IKCa blockade in controls, chronic heart failure (HF) and HF with sustained atrial fibrillation. We used perforated patch action potential recordings to maintain intrinsic calcium cycling. The IKCa blocker (apamin 100 nM) was used to examine the role of the current in atrial and ventricular myocytes. A canine tachypacing induced model of HF (1 and 4 months, n = 5 per group) was used, and compared to a group of 4 month HF with 6 weeks of superimposed atrial fibrillation (n = 7). A group of age-matched canine controls were used (n = 8). Human atrial and ventricular myocytes were isolated from explanted end-stage failing hearts which were obtained from transplant recipients, and studied in parallel. Atrial myocyte action potentials were unchanged by IKCa blockade in all of the groups studied. IKCa blockade did not affect ventricular myocyte repolarization in controls. HF caused prolongation of ventricular myocyte action potential repolarization. IKCa blockade caused further prolongation of ventricular repolarization in HF and also caused repolarization instability and early afterdepolarizations. SK2 and SK3 expression in the atria and SK3 in the ventricle were increased in canine heart failure. We conclude that during HF, IKCa blockade in ventricular myocytes results in cellular arrhythmias. Furthermore, our data suggest an important role for IKCa in the maintenance of ventricular repolarization stability during chronic heart failure. Our findings suggest that novel antiarrhythmic therapies should have safety and efficacy evaluated in both atria and ventricles. PMID:25271970

  14. Histopathological Correlates of Global and Segmental Left Ventricular Systolic Dysfunction in Experimental Chronic Chagas Cardiomyopathy.

    PubMed

    de Oliveira, Luciano Fonseca Lemos; Romano, Minna Moreira Dias; de Carvalho, Eduardo Elias Vieira; Cabeza, Jorge Mejia; Salgado, Hélio Cesar; Fazan Júnior, Rubens; Costa, Renata Sesti; da Silva, João Santana; Higuchi, Maria de Lourdes; Maciel, Benedito Carlos; Cunha-Neto, Edécio; Marin-Neto, José Antônio; Simões, Marcus Vinícius

    2016-01-21

    Chronic Chagas cardiomyopathy in humans is characterized by segmental left ventricular wall motion abnormalities (WMA), mainly in the early stages of disease. This study aimed at investigating the detection of WMA and its correlation with the underlying histopathological changes in a chronic Chagas cardiomyopathy model in hamsters. Female Syrian hamsters (n=34) infected with 3.5×10(4) or 10(5) blood trypomastigote Trypanosoma cruzi (Y strain) forms and an uninfected control group (n=7) were investigated. After 6 or 10 months after the infection, the animals were submitted to in vivo evaluation of global and segmental left ventricular systolic function by echocardiography, followed by euthanasia and histological analysis for quantitative assessment of fibrosis and inflammation with tissue sampling in locations coinciding with the left ventricular wall segmentation employed at the in vivo echocardiographic evaluation. Ten of the 34 infected animals (29%) showed reduced left ventricular ejection fraction (<73%). Left ventricular ejection fraction was more negatively correlated with the intensity of inflammation (r=-0.63; P<0.0001) than with the extent of fibrosis (r=-0.36; P=0.036). Among the 24 animals with preserved left ventricular ejection fraction (82.9±5.5%), 8 (33%) showed segmental WMA predominating in the apical, inferior, and posterolateral segments. The segments exhibiting WMA, in comparison to those with normal wall motion, showed a greater extent of fibrosis (9.3±5.7% and 7±6.3%, P<0.0001) and an even greater intensity of inflammation (218.0±111.6 and 124.5±84.8 nuclei/mm², P<0.0001). Isolated WMA with preserved global systolic left ventricular function is frequently found in Syrian hamsters with experimental chronic Chagas cardiomyopathy whose underlying histopathological features are mainly inflammatory. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  15. Pacemaker current i(f) in adult canine cardiac ventricular myocytes.

    PubMed Central

    Yu, H; Chang, F; Cohen, I S

    1995-01-01

    1. Single cells enzymatically isolated from canine ventricle and canine Purkinje fibres were studied with the whole-cell patch clamp technique, and the properties of the pacemaker current i(f) compared. 2. Steady-state i(f) activation occurred in canine ventricular myocytes at more negative potentials (-120 to -170 mV) than in canine Purkinje cells (-80 to -130 mV). 3. Reversal potentials were obtained in various extracellular Na+ (140, 79 or 37 mM) and K+ concentrations (25, 9 or 5.4 mM) to determine the ionic selectivity of i(f) in the ventricle. The results suggest that this current was carried by both sodium and potassium ions. 4. The plots of the time constants of i(f) activation against voltage were 'bell shaped' in both canine ventricular and Purkinje myocytes. The curve for the ventricular myocytes was shifted about 30 mV in the negative direction. In both ventricular and Purkinje myocytes, the fully activated I-V relationship exhibited outward rectification in 5.4 mM extracellular K+. 5. Calyculin A (0.5 microM) increased i(f) by shifting its activation to more positive potentials in ventricular myocytes. Protein kinase inhibition by H-7 (200 microM) or H-8 (100 microM) reversed the positive voltage shift of i(f) activation. This effect of calyculin A also occurred when the permeabilized patch was used for whole-cell recording. 6. These results indicate i(f) is present in ventricular myocytes. If shifted to more positive potentials i(f) could play a role in ischaemia-induced ventricular arrhythmias. The negative shift of i(f) in the ventricle might play a role in differentiating non-pacing regions of the heart from those regions that pace. PMID:7545232

  16. Self-inflicted ventricular septal defect

    PubMed Central

    Leaver, D. G.; Sharma, R. N.; Glennie, J. S.

    1970-01-01

    A case of attempted suicide is described which is believed to be the first reported example of survival after a self-inflicted penetrating knife wound of the heart. The 12 cm. blade entered the right ventricle and damaged one of the papillary muscles. The ventricular septum was also perforated. At cardiotomy the stab wound in the free wall of the right ventricle was surtured and the papillary muscle repaired. The ventricular septal defect was closed, but a small left-to-right shunt at ventricular level reappeared after operation. Images PMID:5433343

  17. Ventricular-Vascular Interaction in Heart Failure

    PubMed Central

    Borlaug, Barry A.; Kass, David A.

    2008-01-01

    Synopsis Nearly half of all patients with heart failure have preserved ejection fraction (HFpEF). HFpEF patients tend to be older, female, and hypertensive, and characteristically display increased ventricular and arterial stiffening. In this review, we discuss the pathophysiology of abnormal ventriculoarterial stiffening and how the latter affects ventricular function, cardiovascular hemodynamics, reserve capacity, and symptoms. We conclude by exploring how novel treatment strategies targeting abnormal ventricular-arterial interaction might prove useful in the treatment of patients with HFpEF. PMID:18313622

  18. An Unusual Left Ventricular Apical Mass

    PubMed Central

    Cavallero, Erika; Curzi, Mirko; Cioccarelli, Sara Anna; Papalia, Giulio; Ornaghi, Diego; Bragato, Renato Maria

    2014-01-01

    Left ventricular apical masses constitute a rare finding. Imaging properties together with the clinical history of the patient usually allow an etiologic definition. We report a challenging case of an ambiguous left ventricular apical mass of uncertain nature till histological examination. Points of interest were singular clinical history and echocardiographic findings, although not conclusive in hypothesis generating. Furthermore to the best of our knowledge, this is one of the rare attempt to excise a deep left ventricular mass with a mini-invasive surgical approach. PMID:28465915

  19. Ventricular fibrillation via torsade des pointes of cardiac sarcoidosis with preserved left ventricular ejection fraction.

    PubMed

    Sekihara, Takayuki; Nakane, Eisaku; Nakasone, Kazutaka; Inoko, Moriaki

    2016-10-25

    Generally, low left ventricular ejection fraction (LVEF) is a risk for ventricular arrhythmia in patients with cardiac sarcoidosis. We present a case of cardiac sarcoidosis with preserved LVEF that evoked ventricular fibrillation (VF). A 73-year-old woman with VF presented to our emergency department. She had a history of ocular sarcoidosis, with gradual thinning of the basal intraventricular septum. LVEF was 62% on the most recent echocardiography. The electrocardiogram after defibrillation showed complete atrioventricular block (CAVB) with QT segment prolongation and frequent ventricular premature beats. VF via torsade des pointes (TdP) was suspected, and temporary intravenous ventricular pacing and magnesium sulfate infusion suppressed her VF. Cardiac sarcoidosis was diagnosed, and an implantable cardioverter defibrillator was implanted. Patients with cardiac sarcoidosis with CAVB are at risk of evoking VF via TdP regardless of LVEF. If cardiac sarcoidosis is suspected, early diagnosis and risk stratification of ventricular arrhythmia are important. 2016 BMJ Publishing Group Ltd.

  20. Benchmarking ventricular arrhythmias in the mouse--revisiting the 'Lambeth Conventions' 20 years on.

    PubMed

    Huggins, Catherine E; Bell, James R; Pepe, Salvatore; Delbridge, Lea M D

    2008-12-01

    The isolated Langendorff-mode perfused heart has become a valuable experimental model, used extensively to examine cardiac function, pathophysiology and pharmacology. For the clinical cardiologist an ECG is often a simple practicality, however in experimental circumstances, particularly with ex vivo murine hearts it is not always possible to obtain an ECG due to experimental recording constraints. However, the mechanical record of ventricular contractile function can be highly informative in relation to electrical state. It is difficult though to achieve consistency in these evaluations of arrhythmia as a validated common reference framework is lacking. In 1988, a group of investigators developed the 'Lambeth Conventions'--a standardised reference for the definition and classification of arrhythmias in animal experimental models of ischaemia, infarction and reperfusion in vivo. Now, two decades later it is timely to revisit the Lambeth Conventions, and to update the guidelines in the context of the marked increase in murine heart study in experimental cardiac pathophysiology. Here we describe an adjunct to the Lambeth Conventions for the reporting of ventricular arrhythmias post-ischaemia in ex vivo mouse hearts when ECG recordings are not employed. Of seven discrete and identifiable patterns of mechanical dysrhythmia observed in reperfusion, five could be classified using conventional ECG terminology: ventricular premature beat, bigeminy, trigeminy, ventricular tachycardia and ventricular fibrillation. Two additional rhythm variations detected from the pressure record are described (potentiated contraction and alternans).

  1. Arrhythmogenic ventricular cardiomyopathy: A paradigm shift from right to biventricular disease

    PubMed Central

    Saguner, Ardan M; Brunckhorst, Corinna; Duru, Firat

    2014-01-01

    Arrhythmogenic ventricular cardiomyopathy (AVC) is generally referred to as arrhythmogenic right ventricular (RV) cardiomyopathy/dysplasia and constitutes an inherited cardiomyopathy. Affected patients may succumb to sudden cardiac death (SCD), ventricular tachyarrhythmias (VTA) and heart failure. Genetic studies have identified causative mutations in genes encoding proteins of the intercalated disk that lead to reduced myocardial electro-mechanical stability. The term arrhythmogenic RV cardiomyopathy is somewhat misleading as biventricular involvement or isolated left ventricular (LV) involvement may be present and thus a broader term such as AVC should be preferred. The diagnosis is established on a point score basis according to the revised 2010 task force criteria utilizing imaging modalities, demonstrating fibrous replacement through biopsy, electrocardiographic abnormalities, ventricular arrhythmias and a positive family history including identification of genetic mutations. Although several risk factors for SCD such as previous cardiac arrest, syncope, documented VTA, severe RV/LV dysfunction and young age at manifestation have been identified, risk stratification still needs improvement, especially in asymptomatic family members. Particularly, the role of genetic testing and environmental factors has to be further elucidated. Therapeutic interventions include restriction from physical exercise, beta-blockers, sotalol, amiodarone, implantable cardioverter-defibrillators and catheter ablation. Life-long follow-up is warranted in symptomatic patients, but also asymptomatic carriers of pathogenic mutations. PMID:24772256

  2. Polymorphic Ventricular Tachycardia/Ventricular Fibrillation and Sudden Cardiac Death in the Normal Heart.

    PubMed

    Shah, Ashok J; Hocini, Meleze; Denis, Arnaud; Derval, Nicolas; Sacher, Frederic; Jais, Pierre; Haissaguerre, Michel

    2016-09-01

    Primary electrical diseases manifest with polymorphic ventricular tachycardia (PMVT) and ventricular fibrillation (VF) and along with idiopathic VF contribute to about 10% of sudden cardiac deaths (SCDs) overall. These disorders include long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, short QT syndrome, and early repolarization syndrome. This article reviews the clinical electrophysiological management of PMVT/VF in a structurally normal heart affected with these disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Premature ventricular beats initiate recurrent ventricular fibrillation in early repolarization syndrome.

    PubMed

    Ahmed, Nauman; Frontera, Antonio; Duncan, Edward; Thomas, Glyn

    2015-04-01

    An early repolarization (ER) pattern on electrocardiography was historically considered a benign finding; however, this finding in the inferior and lateral leads has recently been associated with idiopathic ventricular fibrillation (VF). Here we describe a case of a 29-year-old man with an ER pattern, who experienced recurrent implantable cardioverter-defibrillator (ICD) shocks for ventricular tachycardia (VT) and VF. An ICD interrogation demonstrated how VF and VT were repeatedly initiated by closely coupled premature ventricular beats.

  4. [Ventricular tachycardias originating in the his-purkinje system. Bundle branch reentrant ventricular tachycardias and fascicular ventricular tachycardias].

    PubMed

    Schmidt, Boris; Chun, Kyoung Ryul Julian; Kuck, Karl-Heinz; Ouyang, Feifan

    2009-11-01

    Ventricular tachycardias (VT) associated with the His-Purkinje system may occur in patients with and without organic heart disease. The former may encounter bundle branch reentrant VT, a macroreentrant VT utilizing the specific conduction system. It frequently occurs in patients with preexisting conduction disturbance such as complete left bundle branch block and may be eliminated by catheter ablation of the right bundle branch. After successful ablation, patient's prognosis depends on the presence or absence of structural heart disease.In patients without structural heart disease, VT with right bundle branch block pattern and superior axis, referred to as idiopathic left ventricular tachycardia, is observed. It is a reentrant VT utilizing the posterior left fascicle and the Purkinje network. The two treatment options include antiarrhythmic drug therapy with verapamil or curative catheter ablation.Another form of ventricular arrhythmia originating in the Purkinje network is idiopathic ventricular fibrillation (IVF). Focal triggers from the right and left ventricular Purkinje network induce premature ventricular contractions inducing IVF. This is amenable to catheter ablation leading to a significant reduction in ICD (implantable cardioverter defibrillator) interventions in sudden cardiac death survivors.

  5. Atrial-ventricular differences in rabbit cardiac voltage-gated Na(+) currents: Basis for atrial-selective block by ranolazine.

    PubMed

    Caves, Rachel E; Cheng, Hongwei; Choisy, Stéphanie C; Gadeberg, Hanne C; Bryant, Simon M; Hancox, Jules C; James, Andrew F

    2017-06-10

    Class 1 antiarrhythmic drugs are highly effective in restoring and maintaining sinus rhythm in atrial fibrillation patients but carry a risk of ventricular tachyarrhythmia. The antianginal agent ranolazine is a prototypic atrial-selective voltage-gated Na(+) channel blocker but the mechanisms underlying its atrial-selective action remain unclear. The present study examined the mechanisms underlying the atrial-selective action of ranolazine. Whole-cell voltage-gated Na(+) currents (INa) were recorded at room temperature (∼22°C) from rabbit isolated left atrial and right ventricular myocytes. INa conductance density was ∼1.8-fold greater in atrial than in ventricular cells. Atrial INa was activated at command potentials ∼7 mV more negative and inactivated at conditioning potentials ∼11 mV more negative than ventricular INa. The onset of inactivation of INa was faster in atrial cells than in ventricular myocytes. Ranolazine (30 μM) inhibited INa in atrial and ventricular myocytes in a use-dependent manner consistent with preferential activated/inactivated state block. Ranolazine caused a significantly greater negative shift in voltage of half-maximal inactivation in atrial cells than in ventricular cells, the recovery from inactivation of INa was slowed by ranolazine to a greater extent in atrial myocytes than in ventricular cells, and ranolazine produced an instantaneous block that showed marked voltage dependence in atrial cells. Differences exist between rabbit atrial and ventricular myocytes in the biophysical properties of INa. The more negative voltage dependence of INa activation and inactivation, together with trapping of the drug in the inactivated channel, underlies an atrial-selective action of ranolazine. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Rest and exercise ventricular function in adults with congenital ventricular septal defects

    SciTech Connect

    Jablonsky, G.; Hilton, J.D.; Liu, P.P.; Morch, J.E.; Druck, M.N.; Bar-Shlomo, B.Z.; McLaughlin, P.R.

    1983-01-15

    Rest and exercise right and left ventricular function were compared using equilibrium gated radionuclide angiography in 19 normal sedentary control subjects and 34 patients with hemodynamically documented congenital ventricular septal defect (VSD). Gated radionuclide angiography was performed at rest and during each level of graded supine bicycle exercise to fatigue. Heart rate, blood pressure, maximal work load achieved, and right and left ventricular ejection fractions were assessed. The control subjects demonstrated an increase in both the left and right ventricular ejection fractions with exercise. All study groups failed to demonstrate an increase in ejection fraction in either ventricle with exercise. Furthermore, resting left ventricular ejection fraction in Groups 2 and 3 was lower than that in the control subjects and resting right ventricular ejection fraction was lower in Group 3 versus control subjects. Thus left and right ventricular function on exercise were abnormal in patients with residual VSD as compared with control subjects; rest and exercise left ventricular ejection fractions remained abnormal despite surgical closure of VSD in the remote past; resting left and right ventricular function was abnormal in patients with Eisenmenger's complex; lifelong volume overload may be detrimental to myocardial function.

  7. Two simultaneous right ventricular tachycardias in a case of arrhythmogenic right ventricular dysplasia.

    PubMed Central

    Buja, G; Martini, B; Nava, A

    1988-01-01

    A 51 year old woman with arrhythmogenic right ventricular dysplasia had two types of ventricular tachycardia--(a) a regular and sustained tachycardia and with normal frontal plane axis on electrocardiography and (b) an irregular non-sustained tachycardia with a leftward frontal plane axis. Changes in the QRS complex were sometimes seen during the sustained ventricular tachycardia. The clinical, electrocardiographic, and electrophysiological data were consistent with the diagnosis of two different and sometimes simultaneous tachycardias originating in the right ventricle. This case suggests a possible new mechanism for the multiform appearances of the ventricular tachycardia. PMID:3395531

  8. Left ventricular function in patients with ventricular arrhythmias and aortic valve disease

    SciTech Connect

    Santinga, J.T.; Kirsh, M.M.; Brady, T.J.; Thrall, J.; Pitt, B.

    1983-02-01

    Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease.

  9. Apical left ventricular hypertrophy and mid-ventricular obstruction in fabry disease.

    PubMed

    Cianciulli, Tomás F; Saccheri, María C; Fernández, Segundo P; Fernández, Cinthia C; Rozenfeld, Paula A; Kisinovsky, Isaac

    2015-05-01

    We report the case of a rare cardiac presentation of Fabry disease. Although concentric left ventricular hypertrophy is a major cardiac finding in Fabry disease, there is no case report of dynamic obstruction at mid-left ventricular level. We describe a 59-year-old-woman suffering from a severe form of Fabry disease, mimicking an apical hypertrophic cardiomyopathy with mid-ventricular obstruction. Differentiation of Fabry disease from hypertrophic cardiomyopathy is crucial given the therapeutic and prognostic differences. Fabry disease should always be suspected in an adult, independently of the pattern of left ventricular hypertrophy.

  10. Genetics Home Reference: catecholaminergic polymorphic ventricular tachycardia

    MedlinePlus

    ... myocytes. During exercise or emotional stress, impaired calcium regulation in the heart can lead to ventricular tachycardia ... mechanisms of arrhythmias associated to impaired Ca(2+) regulation. Heart Rhythm. 2009 Nov;6(11):1652-9. ...

  11. Genetics Home Reference: arrhythmogenic right ventricular cardiomyopathy

    MedlinePlus

    ... Diagnosis and Management Resources (4 links) Brigham and Women's Hospital Cleveland Clinic: How Are Arrhythmias Treated? GeneReview: Arrhythmogenic Right Ventricular Cardiomyopathy St. Luke's-Roosevelt Hospital Center General ...

  12. Premature ventricular contractions: Reassure or refer?

    PubMed

    Akdemir, Baris; YarmohammadI, Hirad; Alraies, M Chadi; Adkisson, Wayne O

    2016-07-01

    When patients present with palpitations, the primary care physician can perform the initial evaluation and treatment for premature ventricular contractions (PVCs). Many patients need only reassurance and do not need to see a cardiologist.

  13. Hydrallazine alone in acute left ventricular failure

    PubMed Central

    Clark, A. J. L.; McMichael, H. B.

    1981-01-01

    A patient presented with severe acute left ventricular failure and was treated with hydrallazine and oxygen alone. He made a rapid and full recovery as judged by clinical, radiological and blood gas evidence. ImagesFig. 1 PMID:7329902

  14. Ventricular repolarization measures for arrhythmic risk stratification

    PubMed Central

    Monitillo, Francesco; Leone, Marta; Rizzo, Caterina; Passantino, Andrea; Iacoviello, Massimo

    2016-01-01

    Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave (QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice. PMID:26839657

  15. [Late ventricular potentials and mitral valve prolapse].

    PubMed

    Babuty, D; Charniot, J C; Delhomme, C; Fauchier, L; Fauchier, J P; Cosnay, P

    1994-03-01

    In order to determine the predictive value for ventricular arrhythmias of ventricular late potentials (LP) in mitral valve prolapse (MVP) the authors performed high amplification signal-averaging ECG (SA) and 24 hours ambulatory ECG (Holter) monitoring in 68 consecutive patients (34 men, 34 women, average age 48 +/- 17.7 years) with echocardiographically diagnosed MVP. Patients with bundle branch block or associated cardiac disease were excluded. Echocardiography showed 26 patients to have floppy mitral valves (38.2%), 50 patients to have posterior deplacement > or = 5 mm of the mitral valves in systole (73.5%) and 35 patients to have mitral regurgitation (51.4%). Holter monitoring showed 17 patients without ventricular extrasystoles (VES), 15 had Lown Grade I, 6 had Lown Grade II, 3 had Lown Grade III, 15 had Lown Grade IV A and 12 had Lown Grade IV B ventricular arrhythmias. Therefore, 30 patients had complex ventricular arrhythmias (> or = Lown Grade III) and 13 patients had spontaneous non-sustained ventricular tachycardia (NSVT) (one patient had NSVT on resting ECG but not on Holter monitoring). Eighteen patients had LP (26.5%). The incidence of complex ventricular arrhythmias was higher in patients with mitral regurgitation (62.8% versus 27.7%; p < 0.005) whereas the incidence of NSVT was not significantly different (25.7% versus 17.1%; p = 0.15). On the other hand, the frequency of complex ventricular arrhythmias was not significantly different in the presence or absence of LP (61.1% versus 40%: NS) whereas the incidence of NSVT was higher in patients with LP (44.4% versus 10%; p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Ventricular Septal Defect from Takotsubo Syndrome

    PubMed Central

    Caplow, Julie; Quatromoni, Neha

    2016-01-01

    Takotsubo Syndrome is a transient condition characterized by left ventricular systolic dysfunction with apical akinesis/dyskinesis and ballooning. Although the prognosis with medical management is excellent in most cases, rare cases of serious complications can occur. We present here a case of a 71-year-old woman presenting with acute decompensated heart failure with initial findings consistent with a myocardial infarction, who was found instead to have an acute ventricular septal defect as a complication of Takotsubo Syndrome. PMID:27563471

  17. Hemodynamic Support for Ventricular Tachycardia Ablation.

    PubMed

    Palaniswamy, Chandrasekar; Miller, Marc A; Reddy, Vivek Y; Dukkipati, Srinivas R

    2017-03-01

    This review discusses the role of hemodynamic support for catheter ablation of unstable ventricular tachycardia, using commercially available mechanical circulatory support devices (intra-aortic balloon pump, Impella, TandemHeart, extracorporeal membrane oxygenation) and analyzes the published clinical experience of the safety and efficacy of these devices during ventricular tachycardia ablation. Appropriate selection of patients, device-specific characteristics, and hemodynamic monitoring is also discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Evaluation of Right Ventricular Systolic Function in Chagas Disease Using Cardiac Magnetic Resonance Imaging.

    PubMed

    Moreira, Henrique T; Volpe, Gustavo J; Marin-Neto, José A; Ambale-Venkatesh, Bharath; Nwabuo, Chike C; Trad, Henrique S; Romano, Minna M D; Pazin-Filho, Antonio; Maciel, Benedito C; Lima, João A C; Schmidt, André

    2017-03-01

    Right ventricular (RV) impairment is postulated to be responsible for prominent systemic congestion in Chagas disease. However, occurrence of primary RV dysfunction in Chagas disease remains controversial. We aimed to study RV systolic function in patients with Chagas disease using cardiac magnetic resonance. This cross-sectional study included 158 individuals with chronic Chagas disease who underwent cardiac magnetic resonance. RV systolic dysfunction was defined as reduced RV ejection fraction based on predefined cutoffs accounting for age and sex. Multivariable logistic regression was used to verify the relationship of RV systolic dysfunction with age, sex, functional class, use of medications for heart failure, atrial fibrillation, and left ventricular systolic dysfunction. Mean age was 54±13 years, 51.2% men. RV systolic dysfunction was identified in 58 (37%) individuals. Although usually associated with reduced left ventricular ejection fraction, isolated RV systolic dysfunction was found in 7 (4.4%) patients, 2 of them in early stages of Chagas disease. Presence of RV dysfunction was not significantly different in patients with indeterminate/digestive form of Chagas disease (35.7%) compared with those with Chagas cardiomyopathy (36.8%) (P=1.000). In chronic Chagas disease, RV systolic dysfunction is more commonly associated with left ventricular systolic dysfunction, although isolated and early RV dysfunction can also be identified. © 2017 American Heart Association, Inc.

  19. [Ablation of idiopathic fascicular ventricular tachycardia].

    PubMed

    Gellér, László; Szilágyi, Szabolcs; Solymossy, Katalin; Srej, Marianna; Zima, Endre; Tahin, Tamás; Merkely, Béla

    2009-08-02

    Idiopathic fascicular ventricular tachycardia is an important and not very rare cardiac arrhythmia with specific electrocardiographic features and therapeutic options. Ventricular tachycardia is characterized by relatively narrow QRS complex and right bundle branch block pattern. The QRS axis depends on which fascicle is involved in the re-entry. Left axis deviation is noted with left posterior fascicular tachycardia and right axis deviation with left anterior fascicular tachycardia. A left septal fascicular tachycardia with normal QRS axis is also possible. Idiopathic fascicular tachycardia is usually seen in individuals without structural heart disease. Response to verapamil is an important feature of fascicular tachycardia. In some cases intravenous adenosine may also terminate the arrhythmia. During electrophysiology study, presystolic or diastolic potentials precede the QRS, presumed to originate from the Purkinje fibers. The potentials can be recorded during sinus rhythm and ventricular tachycardia in many patients with fascicular tachycardia. This potential (so-called Purkinje potential) has been used as a guide to catheter ablation. Correct diagnosis of fascicular tachycardia is very important because catheter ablation is very effective in the treatment of this type of ventricular tachycardia. In this review, we describe three patients with idiopathic ventricular tachycardia and their successful catheter ablation, and summarize the actual knowledge of the diagnosis and management of this special ventricular tachycardia.

  20. Resveratrol reduces intracellular free calcium concentration in rat ventricular myocytes.

    PubMed

    Liu, Zheng; Zhang, Li-Ping; Ma, Hui-Jie; Wang, Chuan; Li, Ming; Wang, Qing-Shan

    2005-10-25

    Resveratrol (trans-3, 4', 5-trihydroxy stilbene), a phytoalexin found in grape skins and red wine, has been reported to have a wide range of biological and pharmacological properties. It has been speculated that resveratrol may have cardioprotective activity. The objective of our study was to investigate the effects of resveratrol on intracellular calcium concentration ([Ca(2+)](i)) in rat ventricular myocytes. [Ca(2+)](i) was detected by laser scanning confocal microscopy. The results showed that resveratrol (15~60 mumol/L) reduced [Ca(2+)](i) in normal and Ca(2+)-free Tyrode's solution in a concentration-dependent manner. The effects of resveratrol on [Ca(2+)](i) in normal Tyrode's solution was partially inhibited by pretreatment with sodium orthovanadate (Na3VO4, 1.0 mmol/L, P<0.01), an inhibitor of protein tyrosine phosphatase, or L-type Ca(2+) channel agonist Bay K8644 (10 mumol/L, P<0.05), but could not be antagonized by NO synthase inhibitor L-NAME (1.0 mmol/L). Resveratrol also markedly inhibited the ryanodine-induced [Ca(2+)](i) increase in Ca(2+)-free Tyrode's solution (P<0.01). When Ca(2+) waves were produced by increasing extracellular Ca(2+) concentration from 1 to 10 mmol/L, resveratrol (60 mumol/L) could reduce the velocity and duration of propagating waves, and block the propagating waves of elevated [Ca(2+)](i). These results suggest that resveratrol may reduce the [Ca(2+)](i) in isolated rat ventricular myocytes. The inhibition of voltage-dependent Ca(2+) channel and tyrosine kinase, and alleviation of Ca(2+) release from sarcoplasmic reticulum (SR) are possibly involved in the effects of resveratrol on rat ventricular myocytes. These findings could help explain the protective activity of resveratrol against cardiovascular disease.

  1. Localizing ventricular tachycardia through entrainment.

    PubMed

    Kuo, C T; Luqman, N; Lin, K H; Chiang, C W

    2000-12-01

    Area(s) of slow conduction are thought to be present within the reentry circuit of most clinically important ventricular tachycardia (VT). To prevent recurrence after ablation of VT late after myocardial infarction, it is desirable to localize and destroy area(s) of slow conduction "critical link" within the reentry circuit. Conventionally, they may be identified by endocardial catheter mapping, continuous electrical activity, mid-diastolic potentials, earliest endocardial activation, pace-mapping etc. However, none of these methods are very specific. Entrainment method may be used to localize the slow conduction zone of reentrant VT. Concealed entrainment is consistent with pacing at a site in the reentry circuit but may also occur at some "bystander" sites that are close to the reentry circuit but are not participating in the circuit itself. During pacing at the slow conduction area of the reentry circuit, the stimulus to QRS (S-QRS) interval should equal the electrogram to QRS (EG-QRS) interval during VT. Similarly the post-pacing interval (PPI) approximates the tachycardia cycle length. During pacing at bystander sites, the S-QRS interval may be greater, less than or equal to the EG-QRS interval, depending on the conduction time from the bystander site to the circuit. The PPI, however, always exceed the tachycardia cycle length. In conjunction with concealed entrainment, the use of diastolic potential, double potentials and continuous electrical activity enhances the prediction of radiofrequency termination of post-infarction VT.

  2. Electrohydraulic ventricular assist device development.

    PubMed

    Diegel, P D; Mussivand, T; Holfert, J W; Juretich, J T; Miller, J A; Maclean, G K; Szurmak, Z; Santerre, J P; Rajagopalan, K; Dew, P A

    1992-01-01

    An electrohydraulic ventricular assist device has been developed. An axial flow pump driven by a brushless DC motor provides actuation. Energy is supplied by internal Ni/Cd batteries and by external Ag/Zn batteries, both rechargeable. Electromagnetic induction is used to pass energy through the skin with a transcutaneous energy transfer (TET) system. Physiologic control, battery management, motor commutation, and communication functions are performed by a surface mount internal controller. An infrared data link within the TET coils provides bidirectional communication between the external and internal controllers. A computer model was developed to predict system performance. The dimensions are 180 mm x 116 mm x 40 mm. An in vitro system pumped 5.7 L/min at 10 mmHg inflow and 100 mmHg outflow pressure. The internal battery can provide the projected energy requirements for 40 min after 540 charge/discharge cycles, and the external battery is capable of 4 hr of operation after 150 cycles. The TET system can deliver 60 W of power and exceeds 80% efficiency between 15 and 30 W. The device configuration is based on human cadaver and intraoperative fit trials. The device is being modified for calf implantation by redirecting the blood ports, increasing the output, and incorporating the internal controller in the unified device base.

  3. [Clinical value of cardiovascular magnetic resonance imaging in the diagnostic work-up of patients with suspected arrhythmogenic right ventricular dysplasia].

    PubMed

    Sánchez-Rubio, Juan; Carreras, Francesc; Pujadas, Sandra; Leta, Rubén; Guillaumet, Eva; Grande, Carlos; Viñolas, Xavier; Pons-Lladó, Guillem

    2005-09-01

    To analyze retrospectively the usefulness of cardiovascular magnetic resonance imaging in the assessment of patients with clinically suspected arrhythmogenic right ventricular dysplasia. We reviewed retrospectively findings from 46 consecutive patients (mean age, 42+/-19 years; 25 male) who were referred for investigation to rule out right ventricular dysplasia. Abnormal findings were classified according to the general diagnostic criteria established by the European Society of Cardiology. Evaluable images were available for all patients. Abnormal right ventricular findings were reported in 24 patients (52%), but only 5 were given a definite diagnosis of right ventricular dysplasia. Fatty infiltration was observed in 9 patients; it was an isolated finding in 6 but was associated with right ventricular contractile dysfunction in 3. These latter patients belonged to the group with confirmed dysplasia. None of the 22 patients (48%) with normal findings on magnetic resonance imaging was given a diagnosis of dysplasia. Cardiovascular magnetic resonance imaging enabled the right ventricle to be assessed in all patients. In those with clinically suspected dysplasia, normal findings ruled out the diagnosis. However, only 21% of those with abnormal findings on magnetic resonance imaging were finally given a confirmed diagnosis of dysplasia. Fatty infiltration of the right ventricular wall does not imply dysplasia unless it is associated with other abnormalities in right ventricular morphology or contractility. Cardiovascular magnetic resonance imaging is useful in the work-up of patients with clinically suspected arrhythmogenic right ventricular dysplasia.

  4. Relation between training-induced left ventricular hypertrophy and risk for ventricular tachyarrhythmias in elite athletes.

    PubMed

    Biffi, Alessandro; Maron, Barry J; Di Giacinto, Barbara; Porcacchia, Paolo; Verdile, Luisa; Fernando, Fredrick; Spataro, Antonio; Culasso, Francesco; Casasco, Maurizio; Pelliccia, Antonio

    2008-06-15

    The aim of this study was to analyze the relation between the magnitude of training-induced left ventricular (LV) hypertrophy and the frequency and complexity of ventricular tachyarrhythmias in a large population of elite athletes without cardiovascular abnormalities. Ventricular tachyarrhythmias are a common finding in athletes, but it is unresolved as to whether the presence or magnitude of LV hypertrophy is a determinant of these arrhythmias in athletes without cardiovascular abnormalities. From 738 athletes examined at a national center for the evaluation of elite Italian athletes, 175 consecutive elite athletes with 24-hour ambulatory (Holter) electrocardiographic recordings (but without cardiovascular abnormalities and symptoms) were selected for the study group. Echocardiographic studies were performed during periods of peak training. Athletes were arbitrarily divided into 4 groups according to the frequency and complexity of ventricular arrhythmias during Holter electrocardiographic monitoring. No statistically significant relation was evident between LV mass (or mass index) and the grade or frequency of ventricular tachyarrhythmias. In addition, a trend was noted in those athletes with the most frequent and complex ventricular ectopy toward lower calculated LV mass. In conclusion, ventricular ectopy in elite athletes is not directly related to the magnitude of physiologic LV hypertrophy. These data offer a measure of clinical reassurance regarding the benign nature of ventricular tachyarrhythmias in elite athletes and the expression of athlete's heart.

  5. [Malignant fascicular ventricular tachycardia degenerating into ventricular fibrillation in a patient with early repolarization syndrome].

    PubMed

    Kane, Ad; Defaye, P; Jacon, P; Mbaye, A; Machecourt, J

    2012-08-01

    A 45-year-old man was hospitalized for syncope due to fascicular ventricular tachycardia degenerating into ventricular fibrillation (VF). The electrocardiogram showed an early repolarization syndrome. The arrhythmia was repetitive and disappeared after oral hydroquinidine. An implantable cardioverter-defibrillator (ICD) was implanted; subsequently, the patient was arrhythmia free at 9 months follow-up.

  6. Continuous Flow Left Ventricular Assist Device Implant Significantly Improves Pulmonary Hypertension, Right Ventricular Contractility, and Tricuspid Valve Competence

    PubMed Central

    Atluri, Pavan; Fairman, Alexander S.; MacArthur, John W.; Goldstone, Andrew B.; Cohen, Jeffrey E.; Howard, Jessica L.; Zalewski, Christyna M.; Shudo, Yasuhiro; Woo, Y. Joseph

    2014-01-01

    Background Continuous flow left ventricular assist devices (CF LVAD) are being implanted with increasing frequency for end-stage heart failure. At the time of LVAD implant, a large proportion of patients have pulmonary hypertension, right ventricular (RV) dysfunction, and tricuspid regurgitation (TR). RV dysfunction and TR can exacerbate renal dysfunction, hepatic dysfunction, coagulopathy, edema, and even prohibit isolated LVAD implant. Repairing TR mandates increased cardiopulmonary bypass time and bicaval cannulation, which should be reserved for the time of orthotopic heart transplantation. We hypothesized that CF LVAD implant would improve pulmonary artery pressures, enhance RV function, and minimize TR, obviating need for surgical tricuspid repair. Methods One hundred fourteen continuous flow LVADs implanted from 2005 through 2011 at a single center, with medical management of functional TR, were retrospectively analyzed. Pulmonary artery pressures were measured immediately prior to and following LVAD implant. RV function and TR were graded according to standard echocardiographic criteria, prior to, immediately following, and long-term following LVAD. Results There was a significant improvement in post-VAD mean pulmonary arterial pressures (26.6 ± 4.9 vs. 30.2 ± 7.4 mmHg, p = 0.008) with equivalent loading pressures (CVP = 12.0 ± 4.0 vs. 12.1 ± 5.1 p = NS). RV function significantly improved, as noted by right ventricular stroke work index (7.04 ± 2.60 vs. 6.05 ± 2.54, p = 0.02). There was an immediate improvement in TR grade and RV function following LVAD implant, which was sustained long term. Conclusion Continuous flow LVAD implant improves pulmonary hypertension, RV function, and tricuspid regurgitation. TR may be managed nonoperatively during CF LVAD implant. PMID:24118109

  7. Continuous flow left ventricular assist device implant significantly improves pulmonary hypertension, right ventricular contractility, and tricuspid valve competence.

    PubMed

    Atluri, Pavan; Fairman, Alexander S; MacArthur, John W; Goldstone, Andrew B; Cohen, Jeffrey E; Howard, Jessica L; Zalewski, Christyna M; Shudo, Yasuhiro; Woo, Y Joseph

    2013-11-01

    Continuous flow left ventricular assist devices (CF LVAD) are being implanted with increasing frequency for end-stage heart failure. At the time of LVAD implant, a large proportion of patients have pulmonary hypertension, right ventricular (RV) dysfunction, and tricuspid regurgitation (TR). RV dysfunction and TR can exacerbate renal dysfunction, hepatic dysfunction, coagulopathy, edema, and even prohibit isolated LVAD implant. Repairing TR mandates increased cardiopulmonary bypass time and bicaval cannulation, which should be reserved for the time of orthotopic heart transplantation. We hypothesized that CF LVAD implant would improve pulmonary artery pressures, enhance RV function, and minimize TR, obviating need for surgical tricuspid repair. One hundred fourteen continuous flow LVADs implanted from 2005 through 2011 at a single center, with medical management of functional TR, were retrospectively analyzed. Pulmonary artery pressures were measured immediately prior to and following LVAD implant. RV function and TR were graded according to standard echocardiographic criteria, prior to, immediately following, and long-term following LVAD. There was a significant improvement in post-VAD mean pulmonary arterial pressures (26.6 ± 4.9 vs. 30.2 ± 7.4 mmHg, p = 0.008) with equivalent loading pressures (CVP = 12.0 ± 4.0 vs. 12.1 ± 5.1 p = NS). RV function significantly improved, as noted by right ventricular stroke work index (7.04 ± 2.60 vs. 6.05 ± 2.54, p = 0.02). There was an immediate improvement in TR grade and RV function following LVAD implant, which was sustained long term. Continuous flow LVAD implant improves pulmonary hypertension, RV function, and tricuspid regurgitation. TR may be managed nonoperatively during CF LVAD implant. © 2013 Wiley Periodicals, Inc.

  8. Outpatient management of intra-corporeal left ventricular assist device system in children: a multi-center experience.

    PubMed

    Schweiger, M; Vanderpluym, C; Jeewa, A; Canter, C E; Jansz, P; Parrino, P E; Miera, O; Schmitto, J; Mehegan, M; Adachi, I; Hübler, M; Zimpfer, D

    2015-02-01

    Little is known about the outcomes of children supported on intracorporeal left ventricular assist device (HVAD), and the feasibility of outpatient management. All centers with pediatric patients discharged from the hospital on the device were identified using company database. A total of 14 centers were contacted, with 9 centers, contributing data retrospectively. From 2011 to 2013, 12 pediatric patients (7 females), mean aged 11.9 ± 2.3 years (range 8-15), mean weight 43 ± 19 kg (range 18-81), mean body surface area 1.3 ± 0.3 m(2) (range 0.76-1.96) were identified. Diagnosis included: dilated cardiomyopathy (CMP) (n = 5), noncompaction CMP (n = 4), toxic CMP (n = 2) and viral CMP (n = 1). Indications for support were permanent support (n = 1), bridge to recovery (n = 1) and bridge to transplantation (n = 10). Prior to HVAD implantation, all patients received intravenous inotropes and two patients were on temporary mechanical support. Overall mortality was 0%. Mean duration of inpatient and outpatient support were 56 (range: 19-95 days) and 290 days (range: 42-790), respectively. Mean readmission rate was 0.02 per patient month (2.1 per patient). No adverse events involving emergency department occurred. Eight children resumed local schooling. Home discharge of children supported on HVAD is feasible and safe. School integration can be achieved. There is wide center variability to discharge practice for children.

  9. Right ventricular assist device with membrane oxygenator support for right ventricular failure following implantable left ventricular assist device placement.

    PubMed

    Leidenfrost, Jeremy; Prasad, Sunil; Itoh, Akinobu; Lawrance, Christopher P; Bell, Jennifer M; Silvestry, Scott C

    2016-01-01

    Cardiogenic shock from refractory right ventricular (RV) failure during left ventricular assist device placement is associated with high morbidity and mortality. The addition of extracorporeal membrane oxygenation to RV mechanical assistance may help RV recovery and lead to improved outcomes. We retrospectively reviewed all implanted continuous-flow left ventricular assist devices from April 2009 to June 2013. RV mechanical support was utilized for RV failure defined as haemodynamic instability despite vasopressors, pulmonary vascular dilators and inotropic therapy. RV assist devices were utilized with and without in-line membrane oxygenation. During the study period, 267 continuous-flow left ventricular assist devices were implanted. RV mechanical support was utilized in 27 (10%) patients; 12 (46%) had the addition of in-line extracorporeal membrane oxygenation. The mean age of patients with a right ventricular assist device with membrane oxygenation was lower than that in patients with a right ventricular assist device alone (45.6 ± 15.9 vs 64.6 ± 6.5, P = 0.001). Support was weaned in 66% (10 of 15) of patients with right ventricular assist device (RVAD) alone vs 83% (10 of 12) of those with RVAD with membrane oxygenation (P = 0.42). The RVAD was removed after 10.4 ± 9.4 vs 5 ± 2.99 days for patients with a RVAD with membrane oxygenation (P = 0.1). Patients with RVAD with membrane oxygenation had a 30-day mortality rate of 8 vs 47% for those with RVAD alone (P = 0.04). The survival rate after discharge was 86, 63 and 54% at 3, 6 and 12 months for both groups combined. Patients with a RVAD with membrane oxygenation support for acute RV failure after continuous-flow left ventricular assist device implantation had a lower 30-day mortality than those with a RVAD alone. Patients who survive to discharge have a reasonable 1-year survival. Combining membrane oxygenation with RVAD support appears to offer a short-term survival benefit in patients with RV failure

  10. Methods for accurate measures of total ventricular activation time.

    PubMed

    Sutherland, D R; Adams, J; Punske, B B

    2006-01-01

    The purpose of this study was to determine improved measures of total ventricular activation time for the diagnosis and treatment of patients undergoing cardiac resynchronization therapy (CRT). This work investigates the accuracy of a root mean square (RMS) based QRS width computed from unipolar electrograms (EGs) measured in heart for representing true total ventricular activation time (TVAT). The study also investigated the use subsets of EGs obtained from the endocardial and epicardial surfaces as indicators of TVAT. Transmural needle electrodes (96) were used to obtain 960 EGs from six normal isolated canine hearts. RMS-based QRS-widths from the endocardial and epicardial surfaces and volume were compared to the TVAT measured from all 960 EGs. No statistically significant differences were found in RMS-based QRS-widths obtained from all three sets of electrograms when compared with true TVAT. Activation times obtained from endocardial and epicardial surfaces were found to be poor indicators of true TVAT. The results support the use of RMS techniques for providing more accurate measures of TVAT.

  11. Exercise thallium testing in ventricular preexcitation

    SciTech Connect

    Archer, S.; Gornick, C.; Grund, F.; Shafer, R.; Weir, E.K.

    1987-05-01

    Ventricular preexcitation, as seen in Wolff-Parkinson-White syndrome, results in a high frequency of positive exercise electrocardiographic responses. Why this occurs is unknown but is not believed to reflect myocardial ischemia. Exercise thallium testing is often used for noninvasive assessment of coronary artery disease in patients with conditions known to result in false-positive electrocardiographic responses. To assess the effects of ventricular preexcitation on exercise thallium testing, 8 men (aged 42 +/- 4 years) with this finding were studied. No subject had signs or symptoms of coronary artery disease. Subjects exercised on a bicycle ergometer to a double product of 26,000 +/- 2,000 (+/- standard error of mean). All but one of the subjects had at least 1 mm of ST-segment depression. Tests were terminated because of fatigue or dyspnea and no patient had chest pain. Thallium test results were abnormal in 5 patients, 2 of whom had stress defects as well as abnormally delayed thallium washout. One of these subjects had normal coronary arteries on angiography with a negative ergonovine challenge, and both had normal exercise radionuclide ventriculographic studies. Delayed thallium washout was noted in 3 of the subjects with ventricular preexcitation and normal stress images. This study suggests that exercise thallium testing is frequently abnormal in subjects with ventricular preexcitation. Ventricular preexcitation may cause dyssynergy of ventricular activation, which could alter myocardial thallium handling, much as occurs with left bundle branch block. Exercise radionuclide ventriculography may be a better test for noninvasive assessment of coronary artery disease in patients with ventricular preexcitation.

  12. Novel Left Ventricular Assist System®

    PubMed Central

    Liotta, Domingo

    2003-01-01

    We propose a Novel Left Ventricular Assist System® (Novel LVAS®) as a bridge to cardiac transplantation and to functional heart recovery in advanced heart failure. This report regards the principles that led to its development. It is our hope that the design of a high-peak-output pump of smaller size will lead to improved functional capacity, when compared with currently available left ventricular assist bridges to heart recovery. Several basic considerations went into the design of this system: 1) we did not want to cannulate the heart chambers; 2) in particular, we rejected the use of a left ventricular apical cannula for myocardial recovery, because it destroys the helical anatomy of the chamber; 3) we chose an atriostomy for blood inflow to the implanted pump; and 4) we synchronized the pump to the patient's electrocardiogram, to ensure blood pump ejection in diastole. The key to success is the atriostomy, which creates an opening larger than the patient's mitral valve. The atriostomy may be performed with the heart beating. Bleeding from the left ventricular apical anastomosis is a fairly common occurrence in currently available left ventricular assist systems; subsequent transfusion can exacerbate right heart dysfunction and sensitize the immune system. These complications are avoided with our system. The new system works either in partial mode or total mode, depending on whether partial or full left ventricular unloading is required. The Novel Left Ventricular Assist System is in its initial clinical trial stage, under the supervision of the author. (Tex Heart Inst J 2003;30:194–201) PMID:12959201

  13. Isolated Pericardial Hydatid Cyst: A Case Report

    PubMed Central

    Cece, Hasan; Yildiz, Sema; Sogut, Ozgur; Hazar, Abdussamet; Sezen, Yusuf

    2011-01-01

    Cardiac echinococcosis is extremely rare, and cysts are found mostly within the myocardium. Most cardiac hydatid cysts are located in the left ventricular wall. Only a few cases of isolated pericardial hydatid cysts have been reported. Echocardiography, computed tomography and magnetic resonance imaging are important diagnostic tools for the diagnosis of echinococcosis. Herein, we report a rare case of isolated pericardial hydatid cyst who presented to our emergency department with complaints of mid-sternal chest pain and shortness of breath.

  14. Risk factors of ventricular tachyarrhythmias after coronary artery bypass grafting.

    PubMed

    Budeus, Marco; Feindt, Peter; Gams, Emmeran; Wieneke, Heinrich; Erbel, Raimund; Sack, Stefan

    2006-11-10

    Ventricular arrhythmias are rare and represent the most serious arrhythmic complication after coronary artery bypass grafting (CABG). The present retrospective study was conducted for identifying patients at risk of ventricular arrhythmias with ventricular signal averaged ECG, standard deviation of all normal RR intervals (SDNN), angiographic and echocardiographic data. We defined ventricular arrhythmias as sustained ventricular fibrillation and ventricular tachycardia. The study population consisted of 209 consecutive patients with sinus rhythm undergoing CABG. The primary endpoint was the occurrence of VA after CABG. The secondary endpoints were hospital length of stay after CABG and the occurrence of VA after hospital discharge. During the postoperative follow-up ventricular arrhythmias were observed in 11 patients (5%). Patients with ventricular arrhythmias showed a higher incidence of ventricular late potentials (91 vs. 9% of patients, p<0.0001) than patients without ventricular arrhythmias. In addition patients with ventricular arrhythmias had a lower left ventricular ejection fraction (44.2+/-15.2 vs. 60.1+/-13.1%, p<0.0001) and a SDNN (22.4+/-8.8 vs. 34.4+/-16.1 ms, p<0.02). A stepwise logistic regression analysis of all variables identified the combination of ventricular late potentials, ejection fraction < or = 38% and SDNN < or = 28 ms (odds rate 26.00; 95% CI, 3.44-196.67, p<0.002) as an independent predictor of ventricular arrhythmias. The results of our study suggest that the probability of ventricular arrhythmias could be predicted after CABG by a combination of low left ventricular ejection fraction and a measurement of ventricular signal averaged ECG and standard deviation of all normal RR intervals. Patients who can be identified as having a high risk of ventricular arrhythmias should be observed carefully after surgery.

  15. Induction of ventricular tachycardia during radiofrequency ablation via pulmonary vein ablation catheter in a patient with an implanted pacemaker.

    PubMed

    Hammwöhner, Matthias; Stachowitz, Jörg; Willich, Tobias; Goette, Andreas

    2012-02-01

    Pulmonary vein isolation in a dual-chamber pacemaker patient using the pulmonary vein ablation catheter (PVAC) system resulted in perpetual induction of ventricular tachycardia (VT) during radio frequency energy application. Induction of VT was abolished by programming the PVAC-system to a pure bipolar ablation mode. Patients with implanted devices should be closely monitored when using the PVAC system in unipolar modes.

  16. Are isolated wetlands isolated?

    USGS Publications Warehouse

    Smith, Loren M.; Euliss, Ned H.; Haukos, David A.

    2011-01-01

    While federal regulations during the past 10 years have treated isolated wetlands as unconnected to aquatic resources protected by the Clean Water Act, they provide critical ecosystem services to society that extend well beyond their wetland boundaries. The authors offer well-documented examples from the scientific literature on some of the ecosystem services provided by isolated wetlands to society and other ecosystems.

  17. Evolution of ventricular myocyte electrophysiology.

    PubMed

    Rosati, Barbara; Dong, Min; Cheng, Lan; Liou, Shian-Ren; Yan, Qinghong; Park, Ji Young; Shiang, Elaine; Sanguinetti, Michael; Wang, Hong-Sheng; McKinnon, David

    2008-11-12

    The relative importance of regulatory versus structural evolution for the evolution of different biological systems is a subject of controversy. The primacy of regulatory evolution in the diversification of morphological traits has been promoted by many evolutionary developmental biologists. For physiological traits, however, the role of regulatory evolution has received less attention or has been considered to be relatively unimportant. To address this issue for electrophysiological systems, we examined the importance of regulatory and structural evolution in the evolution of the electrophysiological function of cardiac myocytes in mammals. In particular, two related phenomena were studied: the change in action potential morphology in small mammals and the scaling of action potential duration across mammalian phylogeny. In general, the functional properties of the ion channels involved in ventricular action potential repolarization were found to be relatively invariant. In contrast, there were large changes in the expression levels of multiple ion channel and transporter genes. For the Kv2.1 and Kv4.2 potassium channel genes, which are primary determinants of the action potential morphology in small mammals, the functional properties of the proximal promoter regions were found to vary in concordance with species-dependent differences in mRNA expression, suggesting that evolution of cis-regulatory elements is the primary determinant of this trait. Scaling of action potential duration was found to be a complex phenomenon, involving changes in the expression of a large number of channels and transporters. In this case, it is concluded that regulatory evolution is the predominant mechanism by which the scaling is achieved.

  18. Left ventricular wall stress compendium.

    PubMed

    Zhong, L; Ghista, D N; Tan, R S

    2012-01-01

    Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models.

  19. Modeling left ventricular diastolic dysfunction: classification and key indicators.

    PubMed

    Luo, Chuan; Ramachandran, Deepa; Ware, David L; Ma, Tony S; Clark, John W

    2011-05-09

    Mathematical modeling can be employed to overcome the practical difficulty of isolating the mechanisms responsible for clinical heart failure in the setting of normal left ventricular ejection fraction (HFNEF). In a human cardiovascular respiratory system (H-CRS) model we introduce three cases of left ventricular diastolic dysfunction (LVDD): (1) impaired left ventricular active relaxation (IR-type); (2) increased passive stiffness (restrictive or R-type); and (3) the combination of both (pseudo-normal or PN-type), to produce HFNEF. The effects of increasing systolic contractility are also considered. Model results showing ensuing heart failure and mechanisms involved are reported. We employ our previously described H-CRS model with modified pulmonary compliances to better mimic normal pulmonary blood distribution. IR-type is modeled by changing the activation function of the left ventricle (LV), and R-type by increasing diastolic stiffness of the LV wall and septum. A 5th-order Cash-Karp Runge-Kutta numerical integration method solves the model differential equations. IR-type and R-type decrease LV stroke volume, cardiac output, ejection fraction (EF), and mean systemic arterial pressure. Heart rate, pulmonary pressures, pulmonary volumes, and pulmonary and systemic arterial-venous O2 and CO2 differences increase. IR-type decreases, but R-type increases the mitral E/A ratio. PN-type produces the well-described, pseudo-normal mitral inflow pattern. All three types of LVDD reduce right ventricular (RV) and LV EF, but the latter remains normal or near normal. Simulations show reduced EF is partly restored by an accompanying increase in systolic stiffness, a compensatory mechanism that may lead clinicians to miss the presence of HF if they only consider LVEF and other indices of LV function. Simulations using the H-CRS model indicate that changes in RV function might well be diagnostic. This study also highlights the importance of septal mechanics in LVDD. The model

  20. Modeling left ventricular diastolic dysfunction: classification and key indicators

    PubMed Central

    2011-01-01

    Background Mathematical modeling can be employed to overcome the practical difficulty of isolating the mechanisms responsible for clinical heart failure in the setting of normal left ventricular ejection fraction (HFNEF). In a human cardiovascular respiratory system (H-CRS) model we introduce three cases of left ventricular diastolic dysfunction (LVDD): (1) impaired left ventricular active relaxation (IR-type); (2) increased passive stiffness (restrictive or R-type); and (3) the combination of both (pseudo-normal or PN-type), to produce HFNEF. The effects of increasing systolic contractility are also considered. Model results showing ensuing heart failure and mechanisms involved are reported. Methods We employ our previously described H-CRS model with modified pulmonary compliances to better mimic normal pulmonary blood distribution. IR-type is modeled by changing the activation function of the left ventricle (LV), and R-type by increasing diastolic stiffness of the LV wall and septum. A 5th-order Cash-Karp Runge-Kutta numerical integration method solves the model differential equations. Results IR-type and R-type decrease LV stroke volume, cardiac output, ejection fraction (EF), and mean systemic arterial pressure. Heart rate, pulmonary pressures, pulmonary volumes, and pulmonary and systemic arterial-venous O2 and CO2 differences increase. IR-type decreases, but R-type increases the mitral E/A ratio. PN-type produces the well-described, pseudo-normal mitral inflow pattern. All three types of LVDD reduce right ventricular (RV) and LV EF, but the latter remains normal or near normal. Simulations show reduced EF is partly restored by an accompanying increase in systolic stiffness, a compensatory mechanism that may lead clinicians to miss the presence of HF if they only consider LVEF and other indices of LV function. Simulations using the H-CRS model indicate that changes in RV function might well be diagnostic. This study also highlights the importance of septal

  1. Ventricular dysphonia: clinical aspects and therapeutic options.

    PubMed

    Maryn, Youri; De Bodt, Marc S; Van Cauwenberge, Paul

    2003-05-01

    Ventricular dysphonia, also known as dysphonia plica ventricularis, refers to the pathological interference of the false vocal folds during phonation. Despite its low incidence and prevalence, Vd is a well-known phenomenon in voice clinics. The present report reviews symptoms, etiology, diagnosis, and therapeutic options regarding this voice disorder. Literature review and case studies. The literature pertaining to all clinical aspects of V(D) was reviewed to define diagnostic and therapeutic clinical decision making. Ventricular dysphonia is characterized by a typical rough, low-pitched voice quality resulting from false vocal fold vibration. Ventricular dysphonia may be compensatory when true vocal folds are affected (resection, paralysis). Noncompensatory types may be of habitual, psychoemotional, or idiopathic origin. Because perceptual symptoms may vary considerably, diagnosis should rely on a meticulous voice assessment, including laryngeal videostroboscopic, perceptual, aerodynamic, and acoustic evaluation. Various therapeutic approaches for the noncompensatory type of ventricular dysphonia may be considered: voice therapy, psychotherapy, anesthetic or botulinum toxin injections, or surgery. The study presents the state of the art with respect to ventricular dysphonia and may be helpful in diagnosis and therapeutic decision-making.

  2. Muscular anatomy of the human ventricular folds.

    PubMed

    Moon, Jerald; Alipour, Fariborz

    2013-09-01

    Our purpose in this study was to better understand the muscular anatomy of the ventricular folds in order to help improve biomechanical modeling of phonation and to better understand the role of these muscles during phonatory and nonphonatory tasks. Four human larynges were decalcified, sectioned coronally from posterior to anterior by a CryoJane tape transfer system, and stained with Masson's trichrome. The total and relative areas of muscles observed in each section were calculated and used for characterizing the muscle distribution within the ventricular folds. The ventricular folds contained anteriorly coursing thyroarytenoid and ventricularis muscle fibers that were in the lower half of the ventricular fold posteriorly, and some ventricularis muscle was evident in the upper and lateral portions of the fold more anteriorly. Very little muscle tissue was observed in the medial half of the fold, and the anterior half of the ventricular fold was largely devoid of any muscle tissue. All 4 larynges contained muscle bundles that coursed superiorly and medially through the upper half of the fold, toward the lateral margin of the epiglottis. Although variability of expression was evident, a well-defined thyroarytenoid muscle was readily apparent lateral to the arytenoid cartilage in all specimens.

  3. Treatment of asymptomatic catecholaminergic polymorphic ventricular tachycardia.

    PubMed

    Obeyesekere, Manoj N; Sy, Raymond W; Leong-Sit, Peter; Gula, Lorne J; Yee, Raymond; Skanes, Allan C; Klein, George J; Krahn, Andrew D

    2012-05-01

    Catecholaminergic polymorphic ventricular tachycardia is a rare genetic disorder caused by mutations in genes involved in the intracellular calcium homeostasis of cardiac cells. Affected patients typically present with life-threatening ventricular arrhythmias precipitated by emotional/physical stress. The diagnosis is based on the demonstration of polymorphic or bidirectional ventricular tachycardia associated with adrenergic stress. Genetic testing can be confirmatory in some patients. Treatment for catecholaminergic polymorphic ventricular tachycardia includes medical and surgical efforts to suppress the effects of epinephrine at the myocardial level and/or modulation of calcium homeostasis. Mortality is high when untreated and sudden cardiac death may be the first manifestation of the disease. First-degree relatives of a proband should be offered genetic testing if the causal mutation is known. If the family mutation is not known, relatives should be clinically evaluated with provocative testing. In the absence of rigorous trials, prophylactic treatment of the asymptomatic catecholaminergic polymorphic ventricular tachycardia patient appears to reduce morbidity and mortality.

  4. Surgical Treatment of Left Ventricular Pseudoaneurysm

    PubMed Central

    Mujanovic, Emir; Bergsland, Jacob; Avdic, Sevleta; Stanimirovic-Mujanovic, Sanja; Kovacevic-Preradovic, Tamara; Kabil, Emir

    2014-01-01

    Introduction: Left ventricular pseudoaneurysm is a rare condition because in most instances ventricular free-wall rupture leads to fatal pericardial tamponade. Rupture of the free wall of the left ventricle is a cata­strophic complication of myocardial infarction, occurring in approximately 4% of pa­tients with infarcts, resulting in immediate collapse of the patient and electromechanical dissociation. In rare cases the rupture is contained by pericardial and fibrous tissue, and the result is a pseudoaneurysm. The left ventricular pseudoaneurysm contains only pericardial and fibrous elements in its wall-no myocardial tissue. Because such aneurysms have a strong tendency to rupture, this disorder may lead to death if it is left surgically untreated. Case report: In this case report, we present a patient who underwent successful repair of a left ventricular pseudoaneurysm, which followed a myocardial infarction that was caused by occlusion of the left circumflex coronary artery. Although repair of left ventricular pseudoaneurysm is still a surgical challenge, it can be performed with acceptable results in most patients. PMID:25568538

  5. Computer simulation of the precordial QRS complex: effects of simulated changes in ventricular wall thickness and volume.

    PubMed

    Salu, Y; Marcus, M L

    1976-12-01

    The cardiac electric field generated by depolarization of the human ventricle is simulated with a computer model which utilizes 1,500 dipoles. The configuration of the ventricles utilized in the model assumed that the cross-sectional shape of the left ventricle was circular and the right ventricular free wall was a portion of an ellipse. The torso was assumed to be homogeneous and infinite. The activation sequence was based on the measurements of Durrer. The depolarizational wave was simulated by dipole layers. The output of the model is presented as a standard multilead precordial ECG. The ECG complexes generated by the model closely resemble the precordial QRS complexes of normal man. Simulated increases in wall thickness (1 to 2.2 X control) were associated with changes in the calculated precordial QRS complexes which were characteristic of left ventricular hypertrophy. Voltage (R in V5 or V6 and S in V1) and QRS duration increased linearly as a function of calculated left ventricular mass. Increases in ventricular activation time were related nonlinearly to changes in left ventricular mass and did not occur in the absence of a simulated increase in wall thickness. The effects of simulated changes in left ventricular volume (0.6 to 3.0 X control) on the QRS complex were mainly dependent on the resultant increase in left ventricular mass. This model may be useful in simulating the precordial QRS complexes that result from isolated or combined changes in ventricular volume or wall thickness or other disorders of the heart. Furthermore, it may be useful whenever a simulation of a QRS generator is needed.

  6. Two potentially fatal surprises in the preoperative assessment of an asymptomatic young adult.

    PubMed

    Lagoeiro Jorge, Antonio José; Alves do Couto, Antonio; Tinoco Mesquita, Evandro; Ribeiro, Mario Luiz; Vale de Souza Junior, Celso; de Andrade Martins, Wolney

    2016-05-01

    Isolated left ventricular non-compaction is a rare disease classified as a primary genetic cardiomyopathy and is characterized by heart failure, systemic embolism and ventricular arrhythmias. The diagnosis is established by Doppler echocardiography. We report the case of an asymptomatic young adult, with no history of heart disease, who underwent preoperative assessment for low-risk orthopedic surgery. The electrocardiogram showed left bundle branch block, which prompted further investigation with Doppler echocardiography, cardiac computed tomography angiography and cardiac magnetic resonance imaging. A diagnosis of isolated left ventricular non-compaction and pulmonary embolism was made. Some aspects of preoperative assessment in low-risk surgical patients are discussed. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  7. Myocardial scar predicts monomorphic ventricular tachycardia but not polymorphic ventricular tachycardia or ventricular fibrillation in nonischemic dilated cardiomyopathy.

    PubMed

    Piers, Sebastiaan R D; Everaerts, Kimberly; van der Geest, Rob J; Hazebroek, Mark R; Siebelink, Hans-Marc; Pison, Laurent A F G; Schalij, Martin J; Bekkers, Sebastiaan C A M; Heymans, Stephane; Zeppenfeld, Katja

    2015-10-01

    The relation between myocardial scar and different types of ventricular arrhythmias in patients with nonischemic dilated cardiomyopathy (NIDCM) is unknown. The purpose of this study was to analyze the effect of myocardial scar, assessed by late gadolinium enhancement cardiac magnetic resonance imaging (LGE-CMR), on the occurrence and type of ventricular arrhythmia in patients with NIDCM. Consecutive patients with NIDCM who underwent LGE-CMR and implantable cardioverter-defibrillator (ICD) implantation at either of 2 centers were included. LGE was defined by signal intensity ≥35% of maximal signal intensity, subdivided into core and border zones (≥50% and 35%-50% of maximal signal intensity, respectively), and categorized according to location (basal or nonbasal) and transmurality. ICD recordings and electrocardiograms were reviewed to determine the occurrence and type of ventricular arrhythmia during follow-up. Of 87 patients (age 56 ± 13 y, 62% male, left ventricular ejection fraction 29% ± 12%), 55 (63%) had LGE (median 6.3 g, interquartile range 0.0-13.8 g). During a median follow-up of 45 months, monomorphic ventricular tachycardia (VT) occurred in 18 patients (21%) and polymorphic VT/ventricular fibrillation (VF) in 10 (11%). LGE predicted monomorphic VT (log-rank, P < .001), but not polymorphic VT/VF (log-rank, P = .40). The optimal cutoff value for the extent of LGE to predict monomorphic VT was 7.2 g (area under curve 0.84). Features associated with monomorphic VT were core extent, basal location, and area with 51%-75% LGE transmurality. Myocardial scar assessed by LGE-CMR predicts monomorphic VT, but not polymorphic VT/VF, in NIDCM. The risk for monomorphic VT is particularly high when LGE shows a basal transmural distribution and a mass ≥7.2 g. Importantly, patients without LGE on CMR remain at risk for potentially fatal polymorphic VT/VF. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  8. Leptin decreases heart rate associated with increased ventricular repolarization via its receptor

    PubMed Central

    Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H.; Hull, Robert; Davis, Mary

    2015-01-01

    Leptin has been proposed to modulate cardiac electrical properties via β-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1–30 μg/kg) decreased resting heart rate; at high doses (150–300 μg/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03–0.3 μg/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of β-adrenergic receptor stimulation. During inhibition of β-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias. PMID:26408544

  9. Leptin decreases heart rate associated with increased ventricular repolarization via its receptor.

    PubMed

    Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H; Hull, Robert; Davis, Mary; Yu, Han-Gang

    2015-11-15

    Leptin has been proposed to modulate cardiac electrical properties via β-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1-30 μg/kg) decreased resting heart rate; at high doses (150-300 μg/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03-0.3 μg/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of β-adrenergic receptor stimulation. During inhibition of β-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias. Copyright © 2015 the American Physiological Society.

  10. CELLULAR MECHANISM OF PREMATURE VENTRICULAR CONTRACTION-INDUCED CARDIOMYOPATHY

    PubMed Central

    Wang, Youhong; Eltit, Jose M.; Kaszala, Karoly; Tan, Alex; Jiang, Min; Zhang, Mei; Tseng, Gea-Ny; Huizar, Jose F.

    2014-01-01

    Background Frequent premature ventricular contractions (PVCs) are associated with increased risk for sudden cardiac death (SCD) and can cause secondary cardiomyopathy (CM). Objective We sought to determine the mechanism(s) responsible for prolonged refractory period and LV dysfunction demonstrated in our canine model of PVC-induced CM. Methods Single myocytes were isolated from LV free wall of PVC and control canines, and used for patch clamp recording, [Ca]i measurements and immunocytochemistry/confocal microscopy. LV tissues adjacent to area of myocyte isolation were used for immunoblot quantification of protein expression. Results In PVC group, LVEF declined from 57.6±1.5% to 30.4±3.1% after ≥ 4 months of ventricular bigeminy. Compared to control myocytes, PVC myocytes had reduced densities of both outward (Ito and IK1) and inward (ICaL) currents, but no consistent changes in IKr or IKs. The reduction in Ito, IK1 and ICaL was accompanied by decreased protein levels of their channel subunits. The degrees of reduction in Ito, IK1 and ICaL varied among PVC myocytes, creating marked heterogeneity in action potential (AP) configurations and durations. PVC myocytes showed impaired Ca-induced Ca release from SR, without increase in SR Ca leak or decrease in SR Ca store. This was accompanied by a decrease in dyad scaffolding protein, junctophilin-2, and loss of Cav1.2 registry with Ca-releasing channels (RyR2). Conclusion PVCs increase dispersion of AP configuration/duration, a risk factor for SCD, due to heterogeneous reduction in Ito, IK1 and ICaL. The E-C coupling is impaired due to decrease in ICaL and Cav1.2 misalignment with respect to RyR2. PMID:25046857

  11. Ventricular remodelling in rabbits with sustained high-fat diet.

    PubMed

    Zarzoso, M; Mironov, S; Guerrero-Serna, G; Willis, B Cicero; Pandit, S V

    2014-05-01

    Excess weight gain and obesity are one of the most serious health problems in the western societies. These conditions enhance risk of cardiac disease and have been linked with increased prevalence for cardiac arrhythmias and sudden death. Our goal was to study the ventricular remodelling occurring in rabbits fed with high-fat diet (HFD) and its potential arrhythmogenic mechanisms. We used 15 NZW rabbits that were randomly assigned to a control (n = 7) or HFD group (n = 8) for 18 weeks. In vivo studies included blood glucose, electrocardiographic, and echocardiographic measurements. Optical mapping was performed in Langendorff-perfused isolated hearts. Body weight (3.69 ± 0.31 vs. 2.94 ± 0.18 kg, P < 0.001) and blood glucose levels (230 ± 61 vs. 141 ± 14 mg dL(-1) , P < 0.05) were higher in the HFD group vs. controls. The rate-corrected QT interval and its dispersion were increased in HFD rabbits vs. controls (169 ± 10 vs. 146 ± 13 ms and 37 ± 11 vs. 9 ± 2 ms, respectively; P < 0.05). Echocardiographic analysis showed morphological and functional alterations in HFD rabbits indicative of left ventricle (LV) hypertrophy. Isolated heart studies revealed no changes in repolarization and propagation properties under conditions of normal extracellular K(+) , suggesting that extrinsic factors could underlie those electrocardiographic modifications. There were no differences in the dynamics of ventricular fibrillation (frequency, wave breaks) in the presence of isoproterenol. However, HFD rabbits showed a small reduction in action potential duration and an increased incidence of arrhythmias during hyperkalaemia. High-fat feeding during 18 weeks in rabbits induced a type II diabetes phenotype, LV hypertrophy, abnormalities in repolarization and susceptibility to arrhythmias during hyperkalaemia. © 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  12. Ultrasound lineal measurements predict ventricular volume in posthaemorrhagic ventricular dilatation in preterm infants.

    PubMed

    Benavente-Fernandez, Isabel; Lubián-Gutierrez, Manuel; Jimenez-Gomez, Gema; Lechuga-Sancho, Alfonso M; Lubián-López, Simon P

    2017-02-01

    Posthaemorrhagic ventricular dilatation (PHVD) is monitored by conventional two-dimensional ultrasound (2DUS). The aims of this study were to determine the volume of the lateral ventricles using three-dimensional ultrasound (3DUS) in preterm infants with PHVD and to evaluate the relationship between volume and linear measurements. Serial 2DUSs and 3DUSs were performed on preterm infants with PHVD admitted to the neonatal intensive care unit at Puerta del Mar Hospital, Cádiz, Spain, from January 2013 to December 2014. The ventricular index, anterior horn width and thalamo-occipital distance were used as ventricular lineal measurements. Ventricular volume was calculated offline. Serial ultrasounds from seven preterm infants were measured. Each linear measurement was significantly associated with volume, and an equation was obtained through a significant multilevel mixed-effects lineal regression model: ventricular volume (cm(3) ) = -11.02 + 0.668*VI + 0.817*AHW + 0.256*TOD. Intra-observer and interobserver agreement was excellent with an intraclass correlation coefficient of 0.99. Lateral ventricular volumes of preterm infants with PHVD could be reliably determined using 3DUS. Ventricular volume could be accurately estimated using three lineal measurements. More studies are needed to address the importance of volume determination in PHVD. ©2016 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  13. Characteristics of ventricular tachycardia ablation in patients with continuous flow left ventricular assist devices.

    PubMed

    Sacher, Frederic; Reichlin, Tobias; Zado, Erica S; Field, Michael E; Viles-Gonzalez, Juan F; Peichl, Petr; Ellenbogen, Kenneth A; Maury, Philippe; Dukkipati, Srinivas R; Picard, Francois; Kautzner, Josef; Barandon, Laurent; Koneru, Jayanthi N; Ritter, Philippe; Mahida, Saagar; Calderon, Joachim; Derval, Nicolas; Denis, Arnaud; Cochet, Hubert; Shepard, Richard K; Corre, Jerome; Coffey, James O; Garcia, Fermin; Hocini, Meleze; Tedrow, Usha; Haissaguerre, Michel; d'Avila, Andre; Stevenson, William G; Marchlinski, Francis E; Jais, Pierre

    2015-06-01

    Left ventricular assist devices (LVADs) are increasingly used as a bridge to cardiac transplantation or as destination therapy. Patients with LVADs are at high risk for ventricular arrhythmias. This study describes ventricular arrhythmia characteristics and ablation in patients implanted with a Heart Mate II device. All patients with a Heart Mate II device who underwent ventricular arrhythmia catheter ablation at 9 tertiary centers were included. Thirty-four patients (30 male, age 58±10 years) underwent 39 ablation procedures. The underlying cardiomyopathy pathogenesis was ischemic in 21 and nonischemic in 13 patients with a mean left ventricular ejection fraction of 17%±5% before LVAD implantation. One hundred and ten ventricular tachycardias (VTs; cycle lengths, 230-740 ms, arrhythmic storm n=28) and 2 ventricular fibrillation triggers were targeted (25 transseptal, 14 retrograde aortic approaches). Nine patients required VT ablation <1 month after LVAD implantation because of intractable VT. Only 10/110 (9%) of the targeted VTs were related to the Heart Mate II cannula. During follow-up, 7 patients were transplanted and 10 died. Of the remaining 17 patients, 13 were arrhythmia-free at 25±15 months. In 1 patient with VT recurrence, change of turbine speed from 9400 to 9000 rpm extinguished VT. Catheter ablation of VT among LVAD recipients is feasible and reasonably safe even soon after LVAD implantation. Intrinsic myocardial scar, rather than the apical cannula, seems to be the dominant substrate. © 2015 American Heart Association, Inc.

  14. Ventricular tachycardia in cardiac sarcoidosis: characterization of ventricular substrate and outcomes of catheter ablation.

    PubMed

    Kumar, Saurabh; Barbhaiya, Chirag; Nagashima, Koichi; Choi, Eue-Keun; Epstein, Laurence M; John, Roy M; Maytin, Melanie; Albert, Christine M; Miller, Amy L; Koplan, Bruce A; Michaud, Gregory F; Tedrow, Usha B; Stevenson, William G

    2015-02-01

    Cardiac sarcoid-related ventricular tachycardia (VT) is a rare disorder; the underlying substrate and response to ablation are poorly understood. We sought to examine the ventricular substrate and outcomes of catheter ablation in this population. Of 435 patients with nonischemic cardiomyopathy referred for VT ablation, 21 patients (5%) had cardiac sarcoidosis. Multiple inducible VTs were observed with mechanism consistent with scar-mediated re-entry in all VTs. Voltage maps showed widespread and confluent right ventricular scarring. Left ventricular scarring was patchy with a predilection for the basal septum, anterior wall, and perivalvular regions. Epicardial right ventricular scar overlay and exceeded the region of corresponding endocardial scar. After ≥1 procedures, ablation abolished ≥1 inducible VT in 90% and eliminated VT storm in 78% of patients; however, multiple residual VTs remained inducible. Failure to abolish all inducible VTs was because of septal intramural circuits or extensive right ventricular scarring. Multiple procedure VT-free survival was 37% at 1 year, but VT control was achievable in the majority of patients with fewer antiarrhythmic drugs compared with preablation (2.1±0.8 versus 1.1±0.8; P<0.001). Patients with cardiac sarcoidosis and VT exhibit ventricular substrate characterized by confluent right ventricular scarring and patchy left ventricular scarring capable of sustaining a large number of re-entrant circuits. Catheter ablation is effective in terminating VT storm and eliminating ≥1 inducible VT in the majority of patients, but recurrences are common. Ablation in conjunction with antiarrhythmic drugs can help palliate VT in this high-risk population. © 2014 American Heart Association, Inc.

  15. Disruption of cardiac cholinergic neurons enhances susceptibility to ventricular arrhythmias

    PubMed Central

    Jungen, Christiane; Scherschel, Katharina; Eickholt, Christian; Kuklik, Pawel; Klatt, Niklas; Bork, Nadja; Salzbrunn, Tim; Alken, Fares; Angendohr, Stephan; Klene, Christiane; Mester, Janos; Klöcker, Nikolaj; Veldkamp, Marieke W.; Schumacher, Udo; Willems, Stephan; Nikolaev, Viacheslav O.; Meyer, Christian

    2017-01-01

    The parasympathetic nervous system plays an important role in the pathophysiology of atrial fibrillation. Catheter ablation, a minimally invasive procedure deactivating abnormal firing cardiac tissue, is increasingly becoming the therapy of choice for atrial fibrillation. This is inevitably associated with the obliteration of cardiac cholinergic neurons. However, the impact on ventricular electrophysiology is unclear. Here we show that cardiac cholinergic neurons modulate ventricular electrophysiology. Mechanical disruption or pharmacological blockade of parasympathetic innervation shortens ventricular refractory periods, increases the incidence of ventricular arrhythmia and decreases ventricular cAMP levels in murine hearts. Immunohistochemistry confirmed ventricular cholinergic innervation, revealing parasympathetic fibres running from the atria to the ventricles parallel to sympathetic fibres. In humans, catheter ablation of atrial fibrillation, which is accompanied by accidental parasympathetic and concomitant sympathetic denervation, raises the burden of premature ventricular complexes. In summary, our results demonstrate an influence of cardiac cholinergic neurons on the regulation of ventricular function and arrhythmogenesis. PMID:28128201

  16. Mechanisms of transplant right ventricular dysfunction.

    PubMed Central

    Van Trigt, P; Bittner, H B; Kendall, S W; Milano, C A

    1995-01-01

    OBJECTIVE: Right ventricular (RV) dysfunction remains the leading cause of early mortality after cardiac transplantation. The effect of brain death and subsequent hypothermic cardioplegic arrest and storage on subsequent post-transplant right ventricular function was examined. SUMMARY BACKGROUND DATA: Right ventricular dysfunction in the donor heart usually is attributed to failure of the donor right ventricle to adapt to the sudden increase in afterload (pulmonary vascular resistance) in the recipient. Strategies to improve ventricular mechanics in the postoperative period are aimed at reducing pulmonary vascular resistance with vasodilators or augmenting right ventricular contractility with inotropic agents. Events occurring in the donor heart (brain death, hypothermic cardioplegic arrest, and storage) also may be directly related to post-transplant RV dysfunction. METHODS: A canine model of brain death and orthotopic cardiac transplantation was used. A dynamic pressure-volume analysis of RV mechanics was performed using micromanometers and sonomicrometric dimension transducers. Systolic function was assessed by measurement of preload recruitable stroke work (PRSW). Brain death was induced in 17 dogs by inflation of an intracranial balloon. Right ventricular function then was assessed serially to 6 hours (PRSW). Right ventricular adrenergic beta receptor density and function was sampled at control and after 6 hours of brain death. The effect of cardioplegic arrest and hypothermic storage was assessed in a second group of 17 dogs, using the same instrumentation and method of RV analysis. RESULTS: A significant decrease in right ventricular PRSW occurred after brain death, with the average decrease being 37% +/- 10.4% from the control. The RV myocardial beta adrenergic receptor density did not significantly change (253 +/- 34 fmol/ng control vs. 336 +/- 54 fmol/ng after brain death). The adenylyl cyclase activity of the RV beta receptor was assessed and was not

  17. Right ventricular outflow tract aneurysm with thrombus

    PubMed Central

    Peer, Syed Murfad; Bhat, P.S. Seetharama; Furtado, Arul Dominic; Chikkatur, Raghavendra

    2012-01-01

    Right ventricular outflow tract (RVOT) aneurysm is a known complication of tetralogy of Fallot repair when a ventriculotomy is done. It leads to RV dysfunction and may require re-operation. We describe a rare instance of a patient who developed an RVOT aneurysm after trans-ventricular repair of tetralogy of Fallot, which was complicated with the formation of a thrombus in the aneurysm sac. The patient underwent re-operation with thrombectomy, excision of the RVOT aneurysm and pulmonary valve replacement. To the best of our knowledge, the occurrence of this combination and its implications have not been reported. PMID:22232231

  18. Ventricular arrhythmias. Clinical recognition and management.

    PubMed

    Nestico, P F; DePace, N L; Morganroth, J

    1984-05-01

    The recognition that patients at high risk for sudden cardiac death can be identified raises our enthusiasm to eliminate some of these risk factors and thus our hope to prevent sudden cardiac death. Although this effect is yet to be shown in cooperative, well-controlled clinical trials, data exist to suggest that this result will be achieved. Thus, the use of antiarrhythmic agents in chronic ventricular ectopy, particularly in patients with left ventricular dysfunction, seems to be warranted, and new and more potent agents to be used for this end will be available in the future.

  19. Frequency Content and Characteristics of Ventricular Conduction

    PubMed Central

    Tereshchenko, Larisa G.; Josephson, Mark E.

    2015-01-01

    The spectrum of frequencies producing the QRS complex has not been fully explored. In this manuscript we review previous studies of QRS frequency content, and discuss our novel method of the conjoint analysis of the ECG signal in six dimensions: in the domain of three space dimensions, in time domain, and in frequency domain. Orbital frequency of QRS loop is introduced as a six-dimensional characteristic of ventricular conduction, which helped to reveal inapparent ventricular conduction, and to characterize electrophysiological substrate. In this paper, we review our novel method in the historical context. PMID:26364232

  20. Cardiomyopathy induced by incessant fascicular ventricular tachycardia.

    PubMed

    Velázquez-Rodríguez, Enrique; Rodríguez-Piña, Horacio; Pacheco-Bouthillier, Alex; Deras-Mejía, Luz María

    2013-01-01

    A 12-year-old girl with symptoms of fatigue, decreased exercise tolerance and progressive dyspnea (New York Heart Association functional class III) with a possible diagnosis of dilated cardiomyopathy secondary to viral myocarditis. Because of incessant wide QRS tachycardia refractory to antiarrhythmic drugs, she was referred for electrophysiological study. The diagnosis was idiopathic left ventricular tachycardia involving the posterior fascicle of the left bundle branch. After successful treatment with radiofrequency catheter ablation guided by a Purkinje potential radiological and echocardiographic evaluation showed complete reversal of left ventricular function in the first 3 months and no recurrence of arrhythmia during 2 years of follow up.

  1. Pattern Organization of Premature Ventricular Heartbeats

    NASA Astrophysics Data System (ADS)

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Ivanov, Plamen; Stanley, H. Eugene; Stanley, Gene; Goldberger, Ary L.

    2000-03-01

    Increased number of premature (abnormal) ventricular beats in a record of heartbeat intervals are known to be associated with an advanced stage of pathology (e.g. congestive heart failure). These abnormal beats usually occur in repeated bursts for relatively short periods of time. Here we ask the question if particular abnormal patterns appear throughout records of heartbeat intervals. We study the temporal organization of specific patterns of ventricular beats in long 24 hour records and their relation to different stages of disease. We analyze the statistical properties of such patterns and combination of patterns by means of crosscorrelation matrices.

  2. Right Ventricular Cardiomyopathy Meeting the Arrhythmogenic Right Ventricular Dysplasia Revised Criteria? Don't Forget Sarcoidosis!

    PubMed Central

    Vasaturo, Sabina; Ploeg, David E.; Buitrago, Guadalupe; Zeppenfeld, Katja; Veselic-Charvat, Maud

    2015-01-01

    A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland. PMID:25995699

  3. Left ventricular cardiac fibroma in a child presenting with ventricular tachycardia.

    PubMed

    Stratemann, Stacy; Dzurik, Yvette; Fish, Frank; Parra, David

    2008-01-01

    Cardiac tumors in children are rare. Although most are histologically benign, they can be associated with life-threatening arrhythmias and sudden death. We report a 7-year-old boy, with a first episode of symptomatic tachycardia, who was found to have a left ventricular (LV) fibroma. He had a normal echocardiogram prior to an electrophysiology study, which revealed a sustained monomorphic ventricular tachycardia and a radio-opacity near the LV apex. These findings prompted a cardiac MRI, which demonstrated a discrete mass on his LV apex and free wall. Our case emphasizes that structural heart disease should be aggressively pursued in children presenting with ventricular tachycardia.

  4. Thoracic Epidural Anesthesia Reduces Right Ventricular Systolic Function With Maintained Ventricular-Pulmonary Coupling.

    PubMed

    Wink, Jeroen; de Wilde, Rob B P; Wouters, Patrick F; van Dorp, Eveline L A; Veering, Bernadette Th; Versteegh, Michel I M; Aarts, Leon P H J; Steendijk, Paul

    2016-10-18

    Blockade of cardiac sympathetic fibers by thoracic epidural anesthesia may affect right ventricular function and interfere with the coupling between right ventricular function and right ventricular afterload. Our main objectives were to study the effects of thoracic epidural anesthesia on right ventricular function and ventricular-pulmonary coupling. In 10 patients scheduled for lung resection, right ventricular function and its response to increased afterload, induced by temporary, unilateral clamping of the pulmonary artery, was tested before and after induction of thoracic epidural anesthesia using combined pressure-conductance catheters. Thoracic epidural anesthesia resulted in a significant decrease in right ventricular contractility (ΔESV25: +25.5 mL, P=0.0003; ΔEes: -0.025 mm Hg/mL, P=0.04). Stroke work, dP/dtMAX, and ejection fraction showed a similar decrease in systolic function (all P<0.05). A concomitant decrease in effective arterial elastance (ΔEa: -0.094 mm Hg/mL, P=0.004) yielded unchanged ventricular-pulmonary coupling. Cardiac output, systemic vascular resistance, and mean arterial blood pressure were unchanged. Clamping of the pulmonary artery significantly increased afterload (ΔEa: +0.226 mm Hg/mL, P<0.001). In response, right ventricular contractility increased (ΔESV25: -26.6 mL, P=0.0002; ΔEes: +0.034 mm Hg/mL, P=0.008), but ventricular-pulmonary coupling decreased (Δ(Ees/Ea) = -0.153, P<0.0001). None of the measured indices showed significant interactive effects, indicating that the effects of increased afterload were the same before and after thoracic epidural anesthesia. Thoracic epidural anesthesia impairs right ventricular contractility but does not inhibit the native positive inotropic response of the right ventricle to increased afterload. Right ventricular-pulmonary arterial coupling was decreased with increased afterload but not affected by the induction of thoracic epidural anesthesia. URL: http

  5. A Case Report of Renal Sympathetic Denervation for the Treatment of Polymorphic Ventricular Premature Complexes

    PubMed Central

    Kiuchi, Márcio Galindo; Vitorio, Frederico Puppim; da Silva, Gustavo Ramalho; Paz, Luis Marcelo Rodrigues; Souto, Gladyston Luiz Lima

    2015-01-01

    Abstract Premature ventricular complexes are very common, appearing most frequently in patients with hypertension, obesity, sleep apnea, and structural heart disease. Sympathetic hyperactivity plays a critical role in the development, maintenance, and aggravation of ventricular arrhythmias. Recently, Armaganijan et al reported the relevance of sympathetic activation in patients with ventricular arrhythmias and suggested a potential role for catheter-based renal sympathetic denervation in reducing the arrhythmic burden. In this report, we describe a 32-year-old hypertensive male patient presenting with a high incidence of polymorphic premature ventricular complexes on a 24 hour Holter monitor. Beginning 1 year prior, the patient experienced episodes of presyncope, syncope, and tachycardia palpitations. The patient was taking losartan 100 mg/day, which kept his blood pressure (BP) under control, and sotalol 160 mg twice daily. Bisoprolol 10 mg/day was used previously but was not successful for controlling the episodes. The 24 hour Holter performed after the onset of sotalol 160 mg twice daily showed a heart rate ranging between 48 (minimum)–78 (average)–119 (maximum) bpm; 14,286 polymorphic premature ventricular complexes; 3 episodes of nonsustained ventricular tachycardia, the largest composed of 4 beats at a rate of 197 bpm; and 14 isolated atrial ectopic beats. Cardiac magnetic resonance imaging with gadolinium perfusion performed at rest and under pharmacological stress with dipyridamole showed increased left atrial internal volume, preserved systolic global biventricular function, and an absence of infarcted or ischemic areas. The patient underwent bilateral renal sympathetic denervation. The only drug used postprocedure was losartan 25 mg/day. Three months after the patient underwent renal sympathetic denervation, the mean BP value dropped to 132/86 mmHg, the mean systolic/diastolic 24 hour ambulatory BP measurement was reduced to 128/83

  6. Posttraumatic aortico-right ventricular fistula: a case study.

    PubMed

    Garcia-Ramirez, J R; Holcombe, D J; Garcia-Gregory, J A

    1990-01-01

    Posttraumatic formation of either aortico-ventricular or coronary arterio-ventricular fistulas are rare, albeit well-documented events. A case is presented involving crush injury to the chest complicated by an acute inferior wall myocardial infarction and later associated with an aortico-right ventricular fistula. Progressive right ventricular dilatation dictated subsequent surgical repair in this case, although similar fistulas without dilatation may safely be observed.

  7. Left-ventricular cavity automated-border detection using an autocovariance technique in echocardiography

    NASA Astrophysics Data System (ADS)

    Morda, Louis S.; Konofagou, Elisa E.

    2005-04-01

    Left-ventricular (LV) segmentation is essential in the early detection of heart disease, where left-ventricular wall motion is being tracked in order to detect ischemia. In this paper, a new method for automated segmentation of the left-ventricular chamber is described. An autocorrelation-based technique isolates the LV cavity from the myocardial wall on 2-D slices of 3D short-axis echocardiograms. A morphological closing function and median filtering are used to generate a uniform border. The proposed segmentation technique is designed to be used in identifying the endocardial border and estimating the motion of the endocardial wall over a cardiac cycle. To this purpose, the proposed technique is particularly successful in border delineation by tracing around structures like papillary muscles and the mitral valve, which constitute the typical obstacle in LV segmentation techniques. The results using this new technique are compared to the manual detection results in short-axis views obtained at the papillary muscle level from 3D datasets in human and canine experiments in vivo. Qualitatively, the automatically-detected borders are highly comparable to the manually-detected borders enclosing regions in the left-ventricular cavity with a relative error within the range of 4.2% - 6%. The new technique constitutes, thus, a robust segmentation method for automated segmentation of endocardial borders and suitable for wall motion tracking for automated detection of ischemia.

  8. Outcomes of Catheter Ablation of Ventricular Tachycardia in the Setting of Structural Heart Disease.

    PubMed

    Betensky, B P; Marchlinski, F E

    2016-07-01

    Sustained ventricular tachycardias are common in the setting of structural heart disease, either due to prior myocardial infarction or a variety of non-ischemic etiologies, including idiopathic dilated cardiomyopathy, hypertrophic cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy. Over the past two decades, percutaneous catheter ablation has evolved dramatically and has become an effective tool for the control of ventricular arrhythmias. Single and multicenter observational studies as well as several prospective randomized trials have begun to investigate long-term outcomes after catheter ablation procedures. These studies encompass a wide range of mapping and ablation techniques, including conventional activation mapping/entrainment criteria, substrate modification guided by pacemapping, late potential and abnormal electrogram ablation, scar de-channeling, and core isolation. While large-scale, multicenter prospective randomized clinical trials are somewhat limited, the published data demonstrate favorable outcomes with respect to a reduction in overall ventricular tachycardia (VT) burden, reduction of implantable cardioverter defibrillator (ICD) shocks, and discontinuation of anti-arrhythmic medications across varying disease subtypes and convincingly support the use of catheter ablation as the standard of care for many patients with VT in the setting of structural heart disease.

  9. Reduced mechanical efficiency in left‐ventricular trabeculae of the spontaneously hypertensive rat

    PubMed Central

    Han, June‐Chiew; Tran, Kenneth; Johnston, Callum M.; Nielsen, Poul M. F.; Barrett, Carolyn J.; Taberner, Andrew J.; Loiselle, Denis S.

    2014-01-01

    Abstract Long‐term systemic arterial hypertension, and its associated compensatory response of left‐ventricular hypertrophy, is fatal. This disease leads to cardiac failure and culminates in death. The spontaneously hypertensive rat (SHR) is an excellent animal model for studying this pathology, suffering from ventricular failure beginning at about 18 months of age. In this study, we isolated left‐ventricular trabeculae from SHR‐F hearts and contrasted their mechanoenergetic performance with those from nonfailing SHR (SHR‐NF) and normotensive Wistar rats. Our results show that, whereas the performance of the SHR‐F differed little from that of the SHR‐NF, both SHR groups performed less stress‐length work than that of Wistar trabeculae. Their lower work output arose from reduced ability to produce sufficient force and shortening. Neither their heat production nor their enthalpy output (the sum of work and heat), particularly the energy cost of Ca2+ cycling, differed from that of the Wistar controls. Consequently, mechanical efficiency (the ratio of work to change of enthalpy) of both SHR groups was lower than that of the Wistar trabeculae. Our data suggest that in hypertension‐induced left‐ventricular hypertrophy, the mechanical performance of the tissue is compromised such that myocardial efficiency is reduced. PMID:25413328

  10. Right Ventricular Failure Post LVAD Implantation Corrected with Biventricular Support: An In Vitro Model.

    PubMed

    Shehab, Sajad; Allida, Sabine M; Davidson, Patricia M; Newton, Phillip J; Robson, Desiree; Jansz, Paul C; Hayward, Christopher S

    Right ventricular failure after left ventricular assist device (LVAD) implantation is associated with high mortality. Management remains limited to pharmacologic therapy and temporary mechanical support. Delayed right ventricular assist device (RVAD) support after LVAD implantation is associated with poorer outcomes. With the advent of miniaturized, durable, continuous flow ventricular assist device systems, chronic RVAD and biventricular assist device (BiVAD) support has been used with some success. The purpose of this study was to assess combined BiVAD and LVAD with delayed RVAD support within a four-elemental mock circulatory loop (MCL) simulating the human cardiovascular system. Our hypothesis was that delayed continuous flow RVAD (RVAD) would produce similar hemodynamic and flow parameters to those of initial BiVAD support. Using the MCL, baseline biventricular heart failure with elevated right and left filling pressures with low cardiac output was simulated. The addition of LVAD within a biventricular configuration improved cardiac output somewhat, but was associated with persistent right heart failure with elevated right-sided filling pressures. The addition of an RVAD significantly improved LVAD outputs and returned filling pressures to normal throughout the circulation. In conclusion, RVAD support successfully restored hemodynamics and flow parameters of biventricular failure supported with isolated LVAD with persistent elevated right atrial pressure.

  11. Witten index for noncompact dynamics

    NASA Astrophysics Data System (ADS)

    Lee, Seung-Joo; Yi, Piljin

    2016-06-01

    Among gauged dynamics motivated by string theory, we find many with gapless asymptotic directions. Although the natural boundary condition for ground states is L 2, one often turns on chemical potentials or supersymmetric mass terms to regulate the infrared issues, instead, and computes the twisted partition function. We point out how this procedure generically fails to capture physical L 2 Witten index with often misleading results. We also explore how, nevertheless, the Witten index is sometimes intricately embedded in such twisted partition functions. For d = 1 theories with gapless continuum sector from gauge multiplets, such as non-primitive quivers and pure Yang-Mills, a further subtlety exists, leading to fractional expressions. Quite unexpectedly, however, the integral L 2 Witten index can be extracted directly and easily from the twisted partition function of such theories. This phenomenon is tied to the notion of the rational invariant that appears naturally in the wall-crossing formulae, and offers a general mechanism of reading off Witten index directly from the twisted partition function. Along the way, we correct early numerical results for some of mathcal{N} = 4 , 8 , 16 pure Yang-Mills quantum mechanics, and count threshold bound states for general gauge groups beyond SU( N ).

  12. Incidence and characteristics of left ventricular false tendons and trabeculations in the normal and pathologic heart by second harmonic echocardiography.

    PubMed

    Tamborini, Gloria; Pepi, Mauro; Celeste, Fabrizio; Muratori, Manuela; Susini, Francesca; Maltagliati, Anna; Veglia, Fabrizio

    2004-04-01

    We sought to review echocardiographic incidence of anomalous images (AI) as false tendons and trabeculations of the left ventricle (LV) in light of recent advancements in echocardiographic evaluation of heart anatomy. In 1580 patients the presence of false tendons, trabeculations, or thrombi was evaluated with transthoracic echocardiography and correlated to clinical characteristics and echocardiographic parameters. Incidence of AI was 46.7% (75% false tendons, 23% trabeculations, 2% thrombi), slightly higher in pathologic (48.9%) than in normal hearts (40.8%). AI were more frequent in male patients (52%) than in female patients (39.7%) and associated with LV dilatation, hypertrophy, and systolic dysfunction. False tendons and trabeculations were not related to age. Male sex was the most significant independent predictor of AI. In 2 patients, isolated LV noncompaction of myocardium was diagnosed and confirmed by magnetic resonance imaging. This study shows a high prevalence of AI for patients with and without pathologic hearts suggesting the need of updating LV echocardiographic anatomy. It also emphasizes the necessity for an awareness of these anatomic variants when evaluating patients for mural thrombi and cardiomyopathies.

  13. Premature Ventricular Contractions and Non-sustained Ventricular Tachycardia: Association with Sudden Cardiac Death, Risk Stratification, and Management Strategies

    PubMed Central

    Sheldon, Seth H; Gard, Joseph J; Asirvatham, Samuel J

    2010-01-01

    Premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia (NSVT) are frequently encountered and a marker of electrocardiomyopathy. In some instances, they increase the risk for sustained ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. While often associated with a primary cardiomyopathy, they have also been known to cause tachycardia-induced cardiomyopathy in patients without preceding structural heart disease. Medical therapy including beta-blockers and class III anti-arrhythmic agents can be effective while implantable cardiac defibrillators (ICD) are indicated in certain patients. Radiofrequency ablation (RFA) is the preferred, definitive treatment in those patients that improve with anti-arrhythmic therapy, have tachycardia-induced cardiomyopathy, or have certain subtypes of PVCs/NSVT. We present a review of PVCs and NSVT coupled with case presentations on RFA of fascicular ventricular tachycardia, left-ventricular outflow tract ventricular tachycardia, and Purkinje arrhythmia leading to polymorphic ventricular tachycardia. PMID:20811538

  14. Adverse ventricular-ventricular interactions in right ventricular pressure load: Insights from pediatric pulmonary hypertension versus pulmonary stenosis.

    PubMed

    Driessen, Mieke M P; Hui, Wei; Bijnens, Bart H; Dragulescu, Andreea; Mertens, Luc; Meijboom, Folkert J; Friedberg, Mark K

    2016-06-01

    Right ventricular (RV) pressure overload has a vastly different clinical course in children with idiopathic pulmonary arterial hypertension (iPAH) than in children with pulmonary stenosis (PS). While RV function is well recognized as a key prognostic factor in iPAH, adverse ventricular-ventricular interactions and LV dysfunction are less well characterized and the pathophysiology is incompletely understood. We compared ventricular-ventricular interactions as hypothesized drivers of biventricular dysfunction in pediatric iPAH versus PS Eighteen iPAH, 16 PS patients and 18 age- and size-matched controls were retrospectively studied. Cardiac cycle events were measured by M-mode and Doppler echocardiography. Measurements were compared between groups using ANOVA with post hoc Dunnet's or ANCOVA including RV systolic pressure (RVSP; iPAH 96.8 ± 25.4 mmHg vs. PS 75.4 ± 18.9 mmHg; P = 0.011) as a covariate. RV-free wall thickening was prolonged in iPAH versus PS, extending beyond pulmonary valve closure (638 ± 76 msec vs. 562 ± 76 msec vs. 473 ± 59 msec controls). LV and RV isovolumetric relaxation were prolonged in iPAH (P < 0.001; LV 102.8 ± 24.1 msec vs. 63.1 ± 13.7 msec; RV 95 [61-165] vs. 28 [0-43]), associated with adverse septal kinetics; characterized by rightward displacement in early systole and leftward displacement in late RV systole (i.e., early LV diastole). Early LV diastolic filling was decreased in iPAH (73 ± 15.9 vs. PS 87.4 ± 14.4 vs. controls 95.8 ± 12.5 cm/sec; P = 0.004). Prolonged RVFW thickening, prolonged RVFW isovolumetric times, and profound septal dyskinesia are associated with interventricular mechanical discoordination and decreased early LV filling in pediatric iPAH much more than PS These adverse mechanics affect systolic and diastolic biventricular efficiency in iPAH and may form the basis for worse clinical outcomes. We used clinically derived data to study the pathophysiology of ventricular-ventricular

  15. Validating a Clinical Prediction Rule for Ventricular Shunt Malfunction.

    PubMed

    Boyle, Tehnaz P; Kimia, Amir A; Nigrovic, Lise E

    2017-01-17

    This study aims to validate a published ventricular shunt clinical prediction rule for the identification of children at low risk for ventricular shunt malfunction based on the absence of 3 high-risk clinical predictors (irritability, nausea or vomiting, and headache). We identified children aged 21 years and younger with a ventricular shunt who presented between 2010 and 2013 to a single pediatric emergency department (ED) for evaluation of potential shunt malfunction. We defined a ventricular shunt malfunction as obstruction to cerebrospinal fluid flow requiring operative neurosurgical intervention within 72 hours of initial ED evaluation. We applied this ventricular shunt clinical prediction rule to the study population and report the test characteristics. We identified 755 ED visits for 294 children with potential ventricular shunt malfunction. Of these encounters, 146 (19%; 95% confidence interval [CI], 17%-22%) had a ventricular shunt malfunction. The ventricular shunt clinical prediction rule had a sensitivity of 99% (95% CI, 94%-100%), specificity of 7% (95% CI, 5%-9%), and negative predictive value of 95% (95% CI, 82%-99%). Two children with a ventricular shunt malfunction were misclassified as low risk by this clinical prediction rule. Ventricular shunt malfunctions were common. Although children classified as low risk by the ventricular shunt clinical prediction rule were less likely to have a shunt malfunction, routine neuroimaging may still be required because exclusion of ventricular shunt malfunction may be difficult on clinical grounds alone.

  16. Determination of ventricular fluid outflow resistance in patients with ventriculomegaly.

    PubMed Central

    Lundar, T; Nornes, H

    1990-01-01

    Resorption of the ventricular fluid was studied by measuring ventricular fluid outflow resistance during steady state 1.5 and 5.0 ml/min infusions in 26 patients with substantial enlargement of the supratentorial ventricular system. This test may avoid unnecessary use of shunts, but a shunt could be introduced during the same procedure. PMID:2266372

  17. Left ventricular pseudoaneurysm perceived as a left lung mass

    PubMed Central

    Yaliniz, Hafize; Gocen, Ugur; Atalay, Atakan; Salih, Orhan Kemal

    2016-01-01

    Left ventricular pseudoaneurysm is a rare complication of aneurysmectomy. We present a case of a surgically treated left ventricular pseudoaneurysm, which was diagnosed three years after coronary artery bypass grafting and left ventricular aneurysmectomy. The presenting symptoms, diagnostic evaluation, and surgical repair are described. PMID:27516793

  18. Right Ventricular Outflow Tract Arrhythmias: Benign Or Early Stage Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia?

    PubMed

    Lin Md, Tina; Conti Md, Sergio; Cipolletta Md, Laura; Marino Md, Vittoria; Zucchetti Md, Martina; Russo Md, Eleonora; Pizzamiglio Md, Francesca; Al-Mohani Md, Ghaliah; Pala Be, Salvatore; Catto Be PhD, Valentina; Di Biase Md PhD, Luigi; Natale Md, Andrea; Tondo Md PhD Fesc, Claudio; Carbucicchio Md, Corrado

    2014-12-01

    Ventricular arrhythmias (VAs) arising from the right ventricular outflow tract (RVOT) are a common and heterogeneous entity. Idiopathic right ventricular arrhythmias (IdioVAs) are generally benign, with excellent ablation outcomes and long-term arrhythmia-free survival, and must be distinguished from other conditions associated with VAs arising from the right ventricle: the differential diagnosis with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is therefore crucial because VAs are one of the most important causes of sudden cardiac death (SCD) in young individuals even with early stage of the disease. Radiofrequency catheter ablation (RFCA) is a current option for the treatment of VAs but important differences must be considered in terms of indication, purposes and procedural strategies in the treatment of the two conditions. In this review, we comprehensively discuss clinical and electrophysiological features, diagnostic and therapeutic techniques in a compared analysis of these two entities.

  19. Left and right ventricular trabecular patterns. Consequence of ventricular septation and valve development.

    PubMed Central

    Wenink, A C; Gittenberger-de Groot, A C

    1982-01-01

    Study of serial sections of human embryos ranging from 3.6 to 25 mm crown rump length shows that the ventricular septum develops from three sources. The primary septum develops between the inlet and outlet which are the two first discernible segments of the ventricular portion of the primary heart tube. Two other septa develop within the inlet and within the outlet, respectively. Before and during septation all ventricular trabeculations are identical. In later stages, the atrioventricular valves and their tension apparatus develop from the inner myocardial layer of the left and right ventricular inlet parts. The outlet trabeculations do not take part in this process. These observations are suggested to explain the typical trabecular patterns of the apices of the mature left and right ventricles, which develop from the inlet and from the outlet, respectively. Images PMID:7138710

  20. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  1. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  2. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  3. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  4. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  5. Ventricular myoarchitecture in tetralogy of Fallot.

    PubMed Central

    Sanchez-Quintana, D.; Anderson, R. H.; Ho, S. Y.

    1996-01-01

    BACKGROUND: Little attention has been paid to the architecture of the muscle fibres of the ventricular walls in congenitally malformed hearts. In this study the gross pattern of myocardial fibres in normal hearts was compared with that in cases of tetralogy of Fallot. METHODS AND RESULTS: After morphological examination nine specimens with tetralogy were dissected to study the ventricular myoarchitecture. Changes were found in the shape of the malformed ventricles. The ventricular walls were arranged in layers in all hearts. Superficial and deep layers were present in both ventricles, with the superficial layer showing a more oblique orientation in the specimens with tetralogy than in normal hearts. Modifications of muscle fibre that were related to the type of malformation were seen in the deep layer. A middle layer was present in the left ventricles of normal hearts and specimens with tetralogy: this showed a horizontal orientation in both groups. In contrast, a middle layer was found in the right ventricle only in specimens showing tetralogy. CONCLUSIONS: The malformed hearts showed modifications in ventricular shape, in the arrangement of muscle in the right ventricle, and in the overall myoarchitecture. These changes could well be the consequence of the same agent (or agents) that caused the structural defect. Images PMID:8868990

  6. Complications of fourth-ventricular shunts.

    PubMed

    Lee, M; Leahu, D; Weiner, H L; Abbott, R; Wisoff, J H; Epstein, F J

    1995-01-01

    Fourth-ventricular shunting is commonly used to treat symptomatic posterior fossa cysts of the Dandy-Walker malformation and trapped fourth ventricle. Although the benefits of this procedure have been widely reported, there is a paucity of data on the pitfalls of posterior fossa shunting in the neurosurgical literature. During the 4-year period from July 1989 to June 1993, we placed fourth-ventricular shunts in 12 patients. Remarkably, 5 patients suffered complications related to posterior fossa catheter placement (42% rate). Three of these patients developed new cranial nerve dysfunction caused by direct injury to the floor of the fourth ventricle, 1 patient suffered an intracystic hemorrhage and acute shunt malfunction, and 1 patient had the catheter tip in the brainstem on postoperative studies without new neurological deficit. We conclude that placement of fourth-ventricular shunts can be fraught with complications which we believe is related to technique. We propose that altering the trajectory of the ventricular catheter from our usual midline technique to a more lateral position will lessen the chances for injury to the floor of the fourth ventricle. In this manner we hope to decrease our incidence of complications for this procedure.

  7. Ventricular myoarchitecture in tetralogy of Fallot.

    PubMed

    Sanchez-Quintana, D; Anderson, R H; Ho, S Y

    1996-09-01

    Little attention has been paid to the architecture of the muscle fibres of the ventricular walls in congenitally malformed hearts. In this study the gross pattern of myocardial fibres in normal hearts was compared with that in cases of tetralogy of Fallot. After morphological examination nine specimens with tetralogy were dissected to study the ventricular myoarchitecture. Changes were found in the shape of the malformed ventricles. The ventricular walls were arranged in layers in all hearts. Superficial and deep layers were present in both ventricles, with the superficial layer showing a more oblique orientation in the specimens with tetralogy than in normal hearts. Modifications of muscle fibre that were related to the type of malformation were seen in the deep layer. A middle layer was present in the left ventricles of normal hearts and specimens with tetralogy: this showed a horizontal orientation in both groups. In contrast, a middle layer was found in the right ventricle only in specimens showing tetralogy. The malformed hearts showed modifications in ventricular shape, in the arrangement of muscle in the right ventricle, and in the overall myoarchitecture. These changes could well be the consequence of the same agent (or agents) that caused the structural defect.

  8. Left ventricular outflow obstruction and necrotizing enterocolitis

    SciTech Connect

    Allen, H.A.; Haney, P.J.

    1984-02-01

    Two neonates had unusually rapid development of necrotizing enterocolitis within 24 hours of birth. Both patients had decreased systemic perfusion secondary to aortic atresia. Onset of either clinical or radiographic manifestations of necrotizing enterocolitis in the first day of life should alert one to the possible presence of severe left ventricular outflow obstruction.

  9. Malignant ventricular arrhythmias in chronic chagasic myocarditis.

    PubMed

    Chiale, P A; Halpern, M S; Nau, G J; Przybylski, J; Tambussi, A M; Lázzari, J O; Elizari, M V; Rosenbaum, M B

    1982-03-01

    We studied 28 cases of chronic chagasic myocarditis (CCM) with frequent ventricular arrhythmias. Two-hundred and three conventional ECGs recorded during 3 months showed ventricular extrasystoles (VE) ranging between 0.2 and 6 per ten beats in 100%; multiform VE in 97.04%; couplets in 79.31%; ventricular tachycardia (VT) in 42.85%; and R on T in 21.67%. A 24-hour continuous recording showed that VE ranged between 3780 and 61733 (mean 16618 +/- 2627); multiform VE and couplets were present in 100% of patients, and VT was present in 78.5%. In 16 patients (group I) the frequency of VE was persistently high, without diurnal variation; 11 patients showed sustained reduction during sleeping hours and only one showed an increase during night sleep (group II). Even in group II, VE never disappeared for periods longer than 10 minutes. In five patients, four 24-hour recordings were obtained at weekly intervals, and in five other patients a second 24-hour recording was performed 10 to 24 months later. The remarkable frequency, persistence and low variability of ventricular arrhythmias in CCM suggest that such arrhythmias can be used as a most stable, reliable, but highly demanding model for testing the efficacy of antiarrhythmic drugs.

  10. APICAL LEFT VENTRICULAR-ABDOMINAL AORTIC COMPOSITE CONDUITS FOR LEFT VENTRICULAR OUTFLOW OBSTRUCTIONS

    PubMed Central

    Cooley, Denton A.; Norman, John C.

    1978-01-01

    Certain problems related to the left ventricular outflow tract are not amenable to conventional surgical methods, but may be solved with the creation of a double outlet left ventricle by using a composite rigid pyrolite left ventricular apex outlet prosthesis and a fabric valve-containing conduit. Low porosity woven Dacron tube grafts are used for the conduit. Twenty-three patients who have undergone apico-aortic bypass with this conduit are reported here, with gratifying results in eighteen. PMID:15216062

  11. Ventricular tachycardia as a first manifestation of right ventricular myxoma--a case presentation.

    PubMed

    Badui, E; Cruz, H; Almazan, A; Enciso, R; Soberanis, N; Garcia, R

    1991-12-01

    The authors present a case of a thirty-nine-year-old white man in good health who developed episodes of ventricular tachycardia as a first manifestation of a right ventricular myxoma, which was diagnosed by two-dimensional echocardiogram and then resected with no complications and total disappearance of the cardiac arrhythmia. After reviewing the literature they consider the present case as a rare manifestation of an infrequent location of an uncommon disease.

  12. Radionuclide analysis of right and left ventricular response to exercise in patients with atrial and ventricular septal defects

    SciTech Connect

    Peter, C.A.; Bowyer, K.; Jones, R.H.

    1983-03-01

    In patients with ventricular or atrial septal defect, the ventricle which is chronically volume overloaded might not appropriately respond to increased demand for an augmentation in output and thereby might limit total cardiac function. In this study we simultaneously measured right and left ventricular response to exercise in 10 normal individuals, 10 patients with ventricular septal defect (VSD), and 10 patients with atrial septal defect (ASD). The normal subjects increased both right and left ventricular ejection fraction, end-diastolic volume, and stroke volume to achieve a higher cardiac output during exercise. Patients with VSD failed to increase right ventricular ejection fraction, but increased right ventricular end-diastolic volume and stroke volume. Left ventricular end-diastolic volume did not increase in these patients but ejection fraction, stroke volume, and forward left ventricular output achieved during exercise were comparable to the response observed in healthy subjects. In the patients with ASD, no rest-to-exercise change occurred in either right ventricular ejection fraction, end-diastolic volume, or stroke volume. In addition, left ventricular end-diastolic volume failed to increase, and despite an increase in ejection fraction, left ventricular stroke volume remained unchanged from rest to exercise. Therefore, cardiac output was augmented only by the heart rate increase in these patients. Right ventricular function appeared to be the major determinant of total cardiac output during exercise in patients with cardiac septal defects and left-to-right shunt.

  13. Cavopulmonary Anastomosis in a Patient With Arrhythmogenic Right Ventricular Cardiomyopathy With Severe Right Ventricular Dysfunction.

    PubMed

    Vaidyanathan, Swaminathan; Kothandam, Sivakumar; Kumar, Rajesh; Indrajith, Sujatha Desai; Agarwal, Ravi

    2017-01-01

    A 26-year-old lady presented with exertional dyspnea, palpitations, central cyanosis, and oxygen saturations of 80% in room air. Her electrocardiogram, echocardiogram, and cardiac magnetic resonance were diagnostic of arrhythmogenic right ventricular dysplasia. There was no documented ventricular arrhythmia or syncopal episodes and Holter recordings were repeatedly normal. Cardiac hemodynamics showed right to left shunt through atrial septal defect, low pulmonary blood flow, normal atrial pressures, and minimally elevated right ventricular end-diastolic pressures. Since her presenting symptoms and cyanosis were attributed to reduced pulmonary blood flow, she underwent off-pump cavopulmonary anastomosis between right superior vena cava and right pulmonary artery. As we intended to avoid the adverse effect of extracorporeal circulation on the myocardial function and pulmonary vasculature, we did not attempt to reduce the size of the atrial septal defect. Her postoperative period was uneventful; oxygen saturation improved to 89% with significant improvement in effort tolerance. At 18-month follow-up, there were no ventricular arrhythmias on surveillance. The clinical presentation of this disease may vary from serious arrhythmias warranting defibrillators and electrical ablations at one end to right ventricular pump failure warranting cardiomyoplasty or right ventricular exclusion procedures at the other end. However, when the presentation was unusual with severe cyanosis through a stretched foramen ovale leading to reduced pulmonary blood flows, Glenn shunt served as a good palliation and should be considered as one of the options in such patients.

  14. Effectiveness of neuroendoscopic ventricular irrigation for ventriculitis.

    PubMed

    Terada, Yukie; Mineharu, Yohei; Arakawa, Yoshiki; Funaki, Takeshi; Tanji, Masahiro; Miyamoto, Susumu

    2016-07-01

    Ventriculitis is an uncommon condition with a poor prognosis, especially when complicated by brain abscess. We compared the therapeutic efficacy of neuroendoscopic ventricular irrigation with those of conventional treatments such as ventricular drainage and continuous irrigation via a ventricular drain. We retrospectively analyzed 14 consecutive patients treated for ventriculitis at our institution between 2001 and 2015. Included were the six patients treated with neuroendoscopic (NE) irrigation (NE group), which we adopted in 2011, and the eight patients treated before 2011 with conventional treatments (non-NE group). We compared mortality, modified Rankin Scale (mRS) score 6 months postoperatively, and duration of ventricular/spinal drainage-catheter placement between groups. Mean age at onset was 49.3 years (range, 32-68 years) in the NE group and 50.3 years (range, 8-78 years) in the non-NE group. At 6-month follow-up, good clinical outcome (mRS≤3) was observed in 66.7% of the NE group, whereas it was observed in 25.0% of the non-NE group. There were three deaths (37.5%) in the non-NE group but none in the NE group. Duration of drainage-catheter placement was significantly shorter in the NE group than in the non-NE group (19.8days vs. 70.9days, p<0.001). Among patients in the NE group, only those who underwent irrigation on the day of diagnosis maintained a low mRS score. Neuroendoscopic ventricular irrigation was safe and effective in the treatment of ventriculitis. Immediate intervention after diagnosis may lead to an improved prognosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Percutaneous epicardial ablation in ventricular arrhythmias.

    PubMed

    Galvão Santos, Pedro; Cavaco, Diogo; Adragão, Pedro; Scanavacca, Mauricio; Reis Santos, Katya; Belo Morgado, Francisco; Carmo, Pedro; Costa, Francisco; Bernardo, Ricardo; Nunes, Manuela; Abecasis, Miguel; Neves, José; Mendes, Miguel

    2014-05-01

    Reentrant circuits of ventricular tachycardia may involve not only the endocardium but also the epicardium. Epicardial ablation can be useful in these situations. The aim of this study was to assess efficacy, safety and complications in a series of consecutive patients who underwent ablation of ventricular tachycardia with epicardial mapping. The study included all patients undergoing ventricular tachycardia ablation with epicardial mapping from 2004 to 2012. Of a total of 95 ablations, an epicardial approach was attempted in nine patients, eight male, mean age 58±12 years. Endocardial mapping was performed in all patients previously or simultaneously. The etiology of the arrhythmia was non-ischemic in eight patients and ischemic in one. We compared the number of events in the six months prior to the epicardial procedure and six months after. Percutaneous epicardial access was achieved in eight patients. In one case it was not possible due to the presence of adhesions. In none of the patients was the procedure repeated and there were no major complications during hospitalization. In a mean follow-up of 3.5±1.2 years, one patient suffered stroke; there were no other medium-to-long-term complications and the number of ventricular tachycardia episodes was reduced in all patients after ablation. Epicardial radiofrequency ablation of ventricular tachycardia was effective in reducing morbidity in eight patients, with a low risk of complications in the short and medium-to-long term. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  16. Acute right ventricular myocarditis presenting with chest pain and syncope

    PubMed Central

    Mancio, Jennifer; Bettencourt, Nuno; Oliveira, Marco; Pires-Morais, Gustavo; Ribeiro, Vasco Gama

    2013-01-01

    Myocarditis is assumed to involve both ventricles equally. Right ventricular predominant involvement is rarely described. A case of acute viral right ventricular myocarditis presenting with chest pain and syncope, grade 3 atrioventricular block, right ventricular dilatation and free wall hypokinesia is reported. Cardiac MRI showed late enhancement of the right ventricular free wall without involvement of the left ventricle. Anti-Coxsackie A9 virus neutralising IgM-type antibodies titre was elevated. This case emphasises that manifestations of myocarditis can be limited to the right ventricle and should be considered in the differential diagnosis of right ventricular enlargement. PMID:24096068

  17. The pathophysiologic process of ventricular remodeling: from infarct to failure.

    PubMed

    Paul, S

    1995-05-01

    In the past, hypertensive heart disease was the principal cause of congestive heart failure, but currently ischemic heart disease is the major etiologic factor. In the last 20 years, the role of myocardial infarction (MI) and the subsequent alteration in ventricular architecture of the infarcted and noninfarcted myocardium have become increasingly associated with a phenomenon known as ventricular remodelling. This process consists of left ventricular wall thinning in the infarction area, ventricular chamber dilatation, and compensatory hypertrophy of the noninfarcted portion of the myocardium. This article describes the pathophysiologic transformation that begins with MI and ventricular remodeling and ends in congestive heart failure.

  18. Young athletes with ventricular premature beats: Continuing or not intense training and competition?

    PubMed

    Parisi, A; Tranchita, E; Minganti, C; Sperandii, F; Guerra, E; Calò, L; Borrione, P; Pigozzi, F

    2017-06-16

    Isolated ventricular premature beats (VPBs) are commonly found during pre-participation screening in athletes. Currently, the debate about the role of detraining in reducing the number of VPBs is still open. This study evaluated the arrhythmic risk in a population of young competitive athletes who showed VPBs during eligibility evaluation and that did not undergo detraining but continued practicing competitive sports. 3746 consecutive subjects underwent pre-participation screening. Athletes who showed VPBs were selected and underwent second level evaluation (Echocardiogram, 24 hour Holter ECG and Exercise test). Athletes were re-evaluated after a follow-up period (6-48 months) while they continued practicing competitive sports. 5.3% of the whole population showed ventricular arrhythmias. 73% of the subjects showed isolated VPBs. 88% of the subjects showed monomorphic VPBs, and 12% of athletes showed polymorphic VPBs. At echocardiogram, there was not any pathology which contraindicated competitive sport activity. At 24 hour Holter ECG recording, mean number of daily VPBs was 1592±3217 (range 0-16678). At holter ECG follow-up (16±12 months), the median number of VPBs decreased from 93 (IQR 20-3065) to a new value of 72 (IQR 2-1299). Continuing competitive sport in subjects with ventricular arrhythmias even though frequent but with a low grade of complexity and without structural cardiomyopathy does not increase sudden death risk. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Obesity, pregnancy, and left ventricular functioning during the third trimester.

    PubMed

    Veille, J C; Hanson, R

    1994-10-01

    Our purpose was to determine left ventricular size and function in obese pregnant patients during the third trimester. Eight morbidly obese pregnant patients had M-mode echocardiography. None were hypertensive or diabetic at the time of study. A group of 36 normal patients were used as controls. Left ventricular end-diastolic dimension, fractional shortening, and cardiac index were not significantly different between the two groups. Left atrial size, left ventricular wall thickness, interventricular septal thickness, and left ventricular mass were greater in the obese group. The radius-to-wall thickness ratio was significantly smaller in the obese group. (1) Left ventricular dimension and function in obese patients was similar to that of nonobese patients. (2) The left ventricle was found to be significantly hypertrophied in obese patients. Left ventricular reconfiguration appears to be important in preserving left ventricular function. Whether these changes are specific to pregnancy or secondary to maternal obesity remains to be determined.

  20. The multiple electrocardiographic manifestations of ventricular repolarization memory.

    PubMed

    Chiale, Pablo A; Etcheverry, Daniel; Pastori, Julio D; Fernandez, Pablo A; Garro, Hugo A; González, Mario D; Elizari, Marcelo V

    2014-08-01

    T wave "memory" is a peculiar variety of cardiac remodeling caused by a transient change in the course of ventricular depolarization (due to ventricular pacing, rate-dependent intraventricular block, ventricular preexcitation or tachyarrhythmias with wide QRS complexes). It is usually manifested by inverted T waves that appears when normal ventricular activation is restored. This phenomenon is cumulative and occurs earlier if the ventricular myocardium has previously been exposed to the same conditioning stimuli. In this article the different conditions giving rise to "classical" T wave memory development are reviewed and also "another" type of T wave memory is described. It is also shown that cardiac memory may induce not only negative (pseudo-primary) T waves but also a reversal of primary and pseudoprimary T waves leading to "normalization" of ventricular repolarization. The knowledge of these dissimilar consequences of T wave memory is essential to assess the characteristics of ventricular repolarization.

  1. Impact of nonischemic scar features on local ventricular electrograms and scar-related ventricular tachycardia circuits in patients with nonischemic cardiomyopathy.

    PubMed

    Sasaki, Takeshi; Miller, Christopher F; Hansford, Rozann; Zipunnikov, Vadim; Zviman, Menekhem M; Marine, Joseph E; Spragg, David; Cheng, Alan; Tandri, Harikrishna; Sinha, Sunil; Kolandaivelu, Aravindan; Zimmerman, Stefan L; Bluemke, David A; Tomaselli, Gordon F; Berger, Ronald D; Halperin, Henry R; Calkins, Hugh; Nazarian, Saman

    2013-12-01

    The association of local electrogram features with scar morphology and distribution in nonischemic cardiomyopathy has not been investigated. We aimed to quantify the association of scar on late gadolinium-enhanced cardiac magnetic resonance with local electrograms and ventricular tachycardia circuit sites in patients with nonischemic cardiomyopathy. Fifteen patients with nonischemic cardiomyopathy underwent late gadolinium-enhanced cardiac magnetic resonance before ventricular tachycardia ablation. The transmural extent and intramural types (endocardial, midwall, epicardial, patchy, transmural) of scar were measured in late gadolinium-enhanced cardiac magnetic resonance short-axis planes. Electroanatomic map points were registered to late gadolinium-enhanced cardiac magnetic resonance images. Myocardial wall thickness, scar transmurality, and intramural scar types were independently associated with electrogram amplitude, duration, and deflections in linear mixed-effects multivariable models, clustered by patient. Fractionated and isolated potentials were more likely to be observed in regions with higher scar transmurality (P<0.0001 by ANOVA) and in regions with patchy scar (versus endocardial, midwall, epicardial scar; P<0.05 by ANOVA). Most ventricular tachycardia circuit sites were located in scar with >25% scar transmurality. Electrogram features are associated with scar morphology and distribution in patients with nonischemic cardiomyopathy. Previous knowledge of electrogram image associations may optimize procedural strategies including the decision to obtain epicardial access.

  2. Cross-sectional echocardiographic left ventricular geometry in rheumatic mitral stenosis.

    PubMed

    Mohan, J C; Agrawala, R; Calton, R; Arora, R

    1993-01-01

    The ultrastructural myopathic changes and deranged left ventricular contractile function have been reported in patients with rheumatic mitral stenosis. It is not clear if as a result of these myopathic changes, global left ventricular myocardial remodelling occurs to alter its normal elliptical shape in the absence of qualitative segmental asynchrony. To study the left ventricular cavity shape independent of chamber size, cross-sectional echocardiographically measured longest long axis (L) of the left ventricular cavity in the apical four-chamber view and short axis diameters at the level of tips of the mitral leaflets in the parasternal long axis view (D-1), of the basal cavity (D-2) and the apical segment (D-3) in the apical four-chamber view at end-diastole and their ratio, were studied in 20 patients with isolated rheumatic mitral stenosis. Twenty healthy volunteers matched for age, sex, heart rate, height and body surface area provided the normal control data. The patients with mitral stenosis had shorter long axis diameter (7.2 +/- 0.7 vs 7.9 +/- 0.5 cm, p < 0.001) and greater short axis/long axis diameter ratios at every level with the most pronounced change in the apical segment of the cavity (D-3/L 0.49 +/- 0.09 vs 0.40 +/- 0.05, p < 0.001). Left ventricular end-diastolic sphericity index was also markedly increased in the patients with mitral stenosis (0.57 +/- 0.09 vs 0.40 +/- 0.05, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Reduced Sialylation Impacts Ventricular Repolarization by Modulating Specific K+ Channel Isoforms Distinctly*

    PubMed Central

    Ednie, Andrew R.; Bennett, Eric S.

    2015-01-01

    Voltage-gated K+ channels (Kv) are responsible for repolarizing excitable cells and can be heavily glycosylated. Cardiac Kv activity is indispensable where even minimal reductions in function can extend action potential duration, prolong QT intervals, and ultimately contribute to life-threatening arrhythmias. Diseases such as congenital disorders of glycosylation often cause significant cardiac phenotypes that can include arrhythmias. Here we investigated the impact of reduced sialylation on ventricular repolarization through gene deletion of the sialyltransferase ST3Gal4. ST3Gal4-deficient mice (ST3Gal4−/−) had prolonged QT intervals with a concomitant increase in ventricular action potential duration. Ventricular apex myocytes isolated from ST3Gal4−/− mice demonstrated depolarizing shifts in activation gating of the transient outward (Ito) and delayed rectifier (IKslow) components of K+ current with no change in maximum current densities. Consistently, similar protein expression levels of the three Kv isoforms responsible for Ito and IKslow were measured for ST3Gal4−/− versus controls. However, novel non-enzymatic sialic acid labeling indicated a reduction in sialylation of ST3Gal4−/− ventricular Kv4.2 and Kv1.5, which contribute to Ito and IKslow, respectively. Thus,