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Sample records for rituximab-induced polymorphic ventricular

  1. Genetics Home Reference: catecholaminergic polymorphic ventricular tachycardia

    MedlinePlus

    ... for This Page Cerrone M, Napolitano C, Priori SG. Catecholaminergic polymorphic ventricular tachycardia: A paradigm to understand ... on PubMed Central Liu N, Ruan Y, Priori SG. Catecholaminergic polymorphic ventricular tachycardia. Prog Cardiovasc Dis. 2008 ...

  2. Catheter ablation of a polymorphic ventricular tachycardia inducing monofocal premature ventricular complex.

    PubMed

    Uemura, Takashi; Yamabe, Hiroshige; Tanaka, Yasuaki; Morihisa, Kenji; Kawano, Hiroaki; Kaikita, Koichi; Sumida, Hitoshi; Sugiyama, Seigo; Ogawa, Hisao

    2008-01-01

    Ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is considered benign, but sometimes it causes polymorphic ventricular tachycardia and ventricular fibrillation, resulting in sudden cardiac death. A 58-year-old woman without structural heart disease was admitted for evaluation of recurrent episodes of syncope. Surface ECG showed frequent repetitive premature ventricular contraction (PVC) of RVOT origin. Polymorphic ventricular tachycardia triggered by the same PVC was documented by Holter ECG during an episode of syncope. Radiofrequency catheter ablation was performed to eradicate this PVC. No polymorphic ventricular tachycardia has developed after the procedure, and the patient has had no recurrence of syncope.

  3. Catecholaminergic polymorphic ventricular tachycardia: a current overview.

    PubMed

    Leite, Luiz R; Henz, Benhur D; Macedo, Paula G; Santos, Simone N; Barreto, José R; Zanatta, André; Fenelon, Guilherme; Cruz Filho, Fernando E S

    2009-03-01

    Catecholaminergic polymorphic ventricular tachycardia occurs in healthy children and young adults causing syncope and sudden cardiac death. This is a familial disease, which affect de novo mutation in 50% of the cases. At least two causative genes have been described to be localized in the chromosome 1; mutation of the ryanodine receptor gene and calsequestrin gene. The classical clinical presentation is syncope triggered by exercise and emotion in children and adolescents with no structural heart disease. Polymorphic ventricular tachycardia during treadmill testing, or after isoproterenol infusion, is the most common feature. Therapeutic options include, beta-blockers, calcium-channel blockers and, an implantable cardioverter defibrillator is indicated in high-risk patients. Risk stratification of this disease is very challenging, since some risk factors proved to be useful in some series but not in others. However, family history of sudden cardiac death and symptoms initiated in very young children are important predictors.

  4. 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. PMID:27521091

  5. Catecholaminergic polymorphic ventricular tachycardia: An exciting new era.

    PubMed

    Behere, Shashank P; Weindling, Steven N

    2016-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a highly malignant inheritable cardiac channelopathy. The past decade and a half has provided exciting new discoveries elucidating the genetic etiology and pathophysiology of CPVT. This review of the current literature on CPVT aims to summarize the state of the art in our understanding of the genetic etiology and the molecular pathogenesis of CPVT, and how these relate to our current approach to diagnosis and management. We will also shed light on groundbreaking new work that will continue to refine the management of CPVT in the future. As our knowledge of CPVT continues to grow, further studies will yield a better understanding of the efficacy and pitfalls of established diagnostic approaches and therapies as well as help shape newer diagnostic and treatment strategies. Two separate searches were run on the National Center for Biotechnology Information's (NCBI) website. The first used the medical subject headings (MeSH) database using the term "catecholaminergic polymorphic ventricular tachycardia" that was run on the PubMed database using the age filter (birth to 18 years), and it yielded 58 results. The second search using the MeSH database with the search term "catecholaminergic polymorphic ventricular tachycardia," applying no filters yielded 178 results. The abstracts of all these articles were studied and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles were further explored and read in full.

  6. Successful control of life-threatening polymorphic ventricular tachycardia by radiofrequency catheter ablation in an infant.

    PubMed

    Abe, Yuriko; Sumitomo, Naokata; Okuma, Hiromi; Nakamura, Takahiro; Fukuhara, Junji; Ichikawa, Rie; Matsumura, Masaharu; Miyashita, Michio; Kamiyama, Hiroshi; Ayusawa, Mamoru; Watanabe, Mamie; Joo, Kunitaka; Makita, Naomasa; Horie, Minoru

    2014-05-01

    We present a case of a 9-month-old girl in whom malignant polymorphic ventricular tachycardia (VT) was successfully controlled by radiofrequency catheter ablation under guidance with a three-dimensional mapping system. The VTs originated from the left ventricular lateral wall, left ventricular anterior wall, and left ventricular apex. At least six types of VTs were documented during the electrophysiology study. All VTs were successfully controlled after two sessions of radiofrequency catheter ablation, and she was discharged from our hospital on propranolol, mexiletine, flecainide, and aprindine. PMID:23836069

  7. Sinus node dysfunction in catecholaminergic polymorphic ventricular tachycardia: risk factor and potential therapeutic target?

    PubMed

    Faggioni, Michela; van der Werf, Christian; Knollmann, Bjorn C

    2014-10-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited heart rhythm disorder characterized by the occurrence of potentially life-threatening polymorphic ventricular tachyarrhythmias in conditions of physical or emotional stress. The underlying cause is a dysregulation in intracellular Ca handling due to mutations in the sarcoplasmic reticulum Ca release unit. Recent experimental work suggests that sinus bradycardia, which is sometimes observed in CPVT patients, may be another primary defect caused by CPVT mutations. Herein, we review the pathophysiology of CPVT and discuss the role of sinus node dysfunction as a modulator of arrhythmia risk and potential therapeutic target.

  8. Sinus node dysfunction in catecholaminergic polymorphic ventricular tachycardia – risk factor and potential therapeutic target?

    PubMed Central

    Faggioni, Michela; van der Werf, Christian; Knollmann, Bjorn

    2014-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited rhythm disorder characterized by the occurrence of potentially life-threatening polymorphic ventricular tachyarrhythmias in conditions of physical or emotional stress. The underlying cause is a dysregulation in intracellular Ca handling due to mutations in the sarcoplasmic reticulum Ca release channel. Recent experimental work suggests that the sinus bradycardia that is sometimes observed in CPVT patients may be another primary defect caused by CPVT mutations. Here, we review the pathophysiology of CPVT and discuss the role of sinus node dysfunction as a modulator of arrhythmia risk and potential therapeutic target. PMID:25112803

  9. The Role of Flecainide in the Management of Catecholaminergic Polymorphic Ventricular Tachycardia

    PubMed Central

    Lieve, Krystien VV; Wilde, Arthur A; van der Werf, Christian

    2016-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare but severe genetic cardiac arrhythmia disorder, with symptoms including syncope and sudden cardiac death due to polymorphic VT or ventricular fibrillation typically triggered by exercise or emotions in the absence of structural heart disease. The cornerstone of medical therapy for CPVT is β-blockers. However, recently flecainide has been added to the therapeutic arsenal for CPVT. In this review we summarise current data on the efficacy and role of flecainide in the treatment of CPVT. PMID:27403293

  10. Prevention of Ventricular Arrhythmia and Calcium Dysregulation in a Catecholaminergic Polymorphic Ventricular Tachycardia Mouse Model Carrying Calsequestrin-2 Mutation

    PubMed Central

    Alcalai, Ronny; Wakimoto, Hiroko; Arad, Michael; Planer, David; Konno, Tetsuo; Wang, Libin; Seidman, Jon G.; Seidman, Christine E.; Berul, Charles I

    2010-01-01

    Background Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial arrhythmic syndrome caused by mutations in genes encoding the calcium-regulation proteins cardiac ryanodine receptor (RyR2) or calsequestrin-2 (CASQ2). Mechanistic studies indicate that CPVT is mediated by diastolic Ca2+ overload and increased Ca2+ leak through the RyR2 channel, implying that treatment targeting these defects might be efficacious in CPVT. Method and results CPVT mouse models that lack CASQ2 were treated with Ca2+-channel inhibitors, β-adrenergic inhibitors, or Mg2+. Treatment effects on ventricular arrhythmia, sarcoplasmic reticulum (SR) protein expression and Ca2+ transients of isolated myocytes were assessed. Each study agent reduced the frequency of stress-induced ventricular arrhythmia in mutant mice. The Ca2+ channel blocker verapamil was most efficacious and completely prevented arrhythmia in 85% of mice. Verapamil significantly increased the SR Ca2+ content in mutant myocytes, diminished diastolic Ca2+ overload, increased systolic Ca2+ amplitude, and prevented Ca2+ oscillations in stressed mutant myocytes. Conclusions Ca2+ channel inhibition by verapamil rectified abnormal calcium handling in CPVT myocytes and prevented ventricular arrhythmias. Verapamil-induced partial normalization of SR Ca2+ content in mutant myocytes implicates CASQ2 as modulator of RyR2 activity, rather than or in addition to, Ca2+ buffer protein. Agents such as verapamil that attenuate cardiomyocyte calcium overload are appropriate for assessing clinical efficacy in human CPVT. PMID:20807279

  11. Teenage pregnancy with catecholaminergic polymorphic ventricular tachycardia and documented ICD discharges.

    PubMed

    Ahmed, Aziez; Phillips, John R

    2016-04-01

    We report the first case of pregnancy in a pediatric patient with catecholiminergic polymorphic ventricular tachycardia (CPVT). Pregnant adolescents with CPVT are at high risk for NSVT and malignant VT during pregnancy, despite antiarrhythmic medication. They may receive multiple implantable cardioverter defibrillator (ICD) therapies. Such patients require close monitoring with special care during the first trimester. PMID:27099728

  12. 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

  13. In silico prediction of drug therapy in catecholaminergic polymorphic ventricular tachycardia

    PubMed Central

    Yang, Pei‐Chi; Moreno, Jonathan D.; Miyake, Christina Y.; Vaughn‐Behrens, Steven B.; Jeng, Mao‐Tsuen; Grandi, Eleonora; Wehrens, Xander H. T.; Noskov, Sergei Y.

    2015-01-01

    Key points The mechanism of therapeutic efficacy of flecainide for catecholaminergic polymorphic ventricular tachycardia (CPVT) is unclear.Model predictions suggest that Na+ channel effects are insufficient to explain flecainide efficacy in CPVT.This study represents a first step toward predicting therapeutic mechanisms of drug efficacy in the setting of CPVT and then using these mechanisms to guide modelling and simulation to predict alternative drug therapies. Abstract Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome characterized by fatal ventricular arrhythmias in structurally normal hearts during β‐adrenergic stimulation. Current treatment strategies include β‐blockade, flecainide and ICD implementation – none of which is fully effective and each comes with associated risk. Recently, flecainide has gained considerable interest in CPVT treatment, but its mechanism of action for therapeutic efficacy is unclear. In this study, we performed in silico mutagenesis to construct a CPVT model and then used a computational modelling and simulation approach to make predictions of drug mechanisms and efficacy in the setting of CPVT. Experiments were carried out to validate model results. Our simulations revealed that Na+ channel effects are insufficient to explain flecainide efficacy in CPVT. The pure Na+ channel blocker lidocaine and the antianginal ranolazine were additionally tested and also found to be ineffective. When we tested lower dose combination therapy with flecainide, β‐blockade and CaMKII inhibition, our model predicted superior therapeutic efficacy than with flecainide monotherapy. Simulations indicate a polytherapeutic approach may mitigate side‐effects and proarrhythmic potential plaguing CPVT pharmacological management today. Importantly, our prediction of a novel polytherapy for CPVT was confirmed experimentally. Our simulations suggest that flecainide therapeutic efficacy in CPVT is unlikely

  14. Analysis of MTHFR and MTRR Gene Polymorphisms in Iranian Ventricular Septal Defect Subjects

    PubMed Central

    Pishva, Seyyed Reza; Vasudevan, Ramachandran; Etemad, Ali; Heidari, Farzad; Komara, Makanko; Ismail, Patimah; Othman, Fauziah; Karimi, Abdollah; Sabri, Mohammad Reza

    2013-01-01

    Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects. PMID:23358257

  15. Analysis of MTHFR and MTRR Gene Polymorphisms in Iranian Ventricular Septal Defect Subjects.

    PubMed

    Pishva, Seyyed Reza; Vasudevan, Ramachandran; Etemad, Ali; Heidari, Farzad; Komara, Makanko; Ismail, Patimah; Othman, Fauziah; Karimi, Abdollah; Sabri, Mohammad Reza

    2013-01-01

    Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects. PMID:23358257

  16. Gender Differences in the Inheritance Mode of RYR2 Mutations in Catecholaminergic Polymorphic Ventricular Tachycardia Patients.

    PubMed

    Ohno, Seiko; Hasegawa, Kanae; Horie, Minoru

    2015-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is one of the causes of sudden cardiac death in young people and results from RYR2 mutations in ~60% of CPVT patients. The inheritance of the RYR2 mutations follows an autosomal dominant trait, however, de novo mutations are often identified during familial analysis. In 36 symptomatic CPVT probands with RYR2 mutations, we genotyped their parents and confirmed the origin of the respective mutation. In 26 sets of proband and both parents (trio), we identified 17 de novo mutations (65.4%), seven from their mothers and only two mutations were inherited from their fathers. Among nine sets of proband and mother, five mutations were inherited from mothers. Four other mutations were of unknown origin. The inheritance of RYR2 mutations was significantly more frequent from mothers (n = 12, 34.3%) than fathers (n = 2, 5.7%) (P = 0.013). The mean ages of onset were not significantly different in probands between de novo mutations and those from mothers. Thus, half of the RYR2 mutations in our cohort were de novo, and most of the remaining mutations were inherited from mothers. These data would be useful for family analysis and risk stratification of the disease.

  17. Catecholaminergic polymorphic ventricular tachycardia: RYR2 mutations, bradycardia, and follow up of the patients

    PubMed Central

    Postma, A; Denjoy, I; Kamblock, J; Alders, M; Lupoglazoff, J; Vaksmann, G; Dubosq-Bidot, L; Sebillon, P; Mannens, M; Guicheney, P; Wilde, A

    2005-01-01

    Background: The aim of the study was to assess underlying genetic cause(s), clinical features, and response to therapy in catecholaminergic polymorphic ventricular tachycardia (CPVT) probands. Methods and results: We identified 13 missense mutations in the cardiac ryanodine receptor (RYR2) in 12 probands with CPVT. Twelve were new, of which two are de novo mutations. A further 11 patients were silent gene carriers, suggesting that some mutations are associated with low penetrance. A marked resting sinus bradycardia off drugs was observed in all carriers. On ß blocker treatment, 98% of the RYR2 mutation carriers remained symptom free with a median follow up of 2 (range: 2–37) years. Conclusion: CPVT patients with RYR2 mutation have bradycardia regardless of the site of the mutation, which could direct molecular diagnosis in (young) patients without structural heart disease presenting with syncopal events and a slow heart rate but with normal QTc at resting ECG. Treatment with ß blockers has been very effective in our CPVT patients during initial or short term follow up. Given the risk of sudden death and the efficacy of ß blocker therapy, the identification of large numbers of RYR2 mutations thus calls for genetic screening, early diagnosis, and subsequent preventive strategies. PMID:16272262

  18. Constitutive Intracellular Na+ Excess in Purkinje Cells Promotes Arrhythmogenesis at Lower Levels of Stress Than Ventricular Myocytes From Mice With Catecholaminergic Polymorphic Ventricular Tachycardia

    PubMed Central

    Willis, B. Cicero; Pandit, Sandeep V.; Ponce-Balbuena, Daniela; Zarzoso, Manuel; Guerrero-Serna, Guadalupe; Limbu, Bijay; Deo, Makarand; Camors, Emmanuel; Ramirez, Rafael J.; Mironov, Sergey; Herron, Todd J.; Valdivia, Héctor H.

    2016-01-01

    Background— In catecholaminergic polymorphic ventricular tachycardia (CPVT), cardiac Purkinje cells (PCs) appear more susceptible to Ca2+ dysfunction than ventricular myocytes (VMs). The underlying mechanisms remain unknown. Using a CPVT mouse (RyR2R4496C+/Cx40eGFP), we tested whether PC intracellular Ca2+ ([Ca2+]i) dysregulation results from a constitutive [Na+]i surplus relative to VMs. Methods and Results— Simultaneous optical mapping of voltage and [Ca2+]i in CPVT hearts showed that spontaneous Ca2+ release preceded pacing-induced triggered activity at subendocardial PCs. On simultaneous current-clamp and Ca2+ imaging, early and delayed afterdepolarizations trailed spontaneous Ca2+ release and were more frequent in CPVT PCs than CPVT VMs. As a result of increased activity of mutant ryanodine receptor type 2 channels, sarcoplasmic reticulum Ca2+ load, measured by caffeine-induced Ca2+ transients, was lower in CPVT VMs and PCs than respective controls, and sarcoplasmic reticulum fractional release was greater in both CPVT PCs and VMs than respective controls. [Na+]i was higher in both control and CPVT PCs than VMs, whereas the density of the Na+/Ca2+ exchanger current was not different between PCs and VMs. Computer simulations using a PC model predicted that the elevated [Na+]i of PCs promoted delayed afterdepolarizations, which were always preceded by spontaneous Ca2+ release events from hyperactive ryanodine receptor type 2 channels. Increasing [Na+]i monotonically increased delayed afterdepolarization frequency. Confocal imaging experiments showed that postpacing Ca2+ spark frequency was highest in intact CPVT PCs, but such differences were reversed on saponin-induced membrane permeabilization, indicating that differences in [Na+]i played a central role. Conclusions— In CPVT mice, the constitutive [Na+]i excess of PCs promotes triggered activity and arrhythmogenesis at lower levels of stress than VMs. PMID:27169737

  19. A human pluripotent stem cell model of catecholaminergic polymorphic ventricular tachycardia recapitulates patient-specific drug responses.

    PubMed

    Preininger, Marcela K; Jha, Rajneesh; Maxwell, Joshua T; Wu, Qingling; Singh, Monalisa; Wang, Bo; Dalal, Aarti; Mceachin, Zachary T; Rossoll, Wilfried; Hales, Chadwick M; Fischbach, Peter S; Wagner, Mary B; Xu, Chunhui

    2016-09-01

    Although β-blockers can be used to eliminate stress-induced ventricular arrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT), this treatment is unsuccessful in ∼25% of cases. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) generated from these patients have potential for use in investigating the phenomenon, but it remains unknown whether they can recapitulate patient-specific drug responses to β-blockers. This study assessed whether the inadequacy of β-blocker therapy in an individual can be observed in vitro using patient-derived CPVT iPSC-CMs. An individual with CPVT harboring a novel mutation in the type 2 cardiac ryanodine receptor (RyR2) was identified whose persistent ventricular arrhythmias during β-blockade with nadolol were abolished during flecainide treatment. iPSC-CMs generated from this patient and two control individuals expressed comparable levels of excitation-contraction genes, but assessment of the sarcoplasmic reticulum Ca(2+) leak and load relationship revealed intracellular Ca(2+) homeostasis was altered in the CPVT iPSC-CMs. β-adrenergic stimulation potentiated spontaneous Ca(2+) waves and unduly frequent, large and prolonged Ca(2+) sparks in CPVT compared with control iPSC-CMs, validating the disease phenotype. Pursuant to the patient's in vivo responses, nadolol treatment during β-adrenergic stimulation achieved negligible reduction of Ca(2+) wave frequency and failed to rescue Ca(2+) spark defects in CPVT iPSC-CMs. In contrast, flecainide reduced both frequency and amplitude of Ca(2+) waves and restored the frequency, width and duration of Ca(2+) sparks to baseline levels. By recapitulating the improved response of an individual with CPVT to flecainide compared with β-blocker therapy in vitro, these data provide new evidence that iPSC-CMs can capture basic components of patient-specific drug responses. PMID:27491078

  20. A human pluripotent stem cell model of catecholaminergic polymorphic ventricular tachycardia recapitulates patient-specific drug responses

    PubMed Central

    Preininger, Marcela K.; Jha, Rajneesh; Maxwell, Joshua T.; Wu, Qingling; Singh, Monalisa; Dalal, Aarti; Mceachin, Zachary T.; Rossoll, Wilfried; Hales, Chadwick M.; Fischbach, Peter S.; Wagner, Mary B.

    2016-01-01

    ABSTRACT Although β-blockers can be used to eliminate stress-induced ventricular arrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT), this treatment is unsuccessful in ∼25% of cases. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) generated from these patients have potential for use in investigating the phenomenon, but it remains unknown whether they can recapitulate patient-specific drug responses to β-blockers. This study assessed whether the inadequacy of β-blocker therapy in an individual can be observed in vitro using patient-derived CPVT iPSC-CMs. An individual with CPVT harboring a novel mutation in the type 2 cardiac ryanodine receptor (RyR2) was identified whose persistent ventricular arrhythmias during β-blockade with nadolol were abolished during flecainide treatment. iPSC-CMs generated from this patient and two control individuals expressed comparable levels of excitation-contraction genes, but assessment of the sarcoplasmic reticulum Ca2+ leak and load relationship revealed intracellular Ca2+ homeostasis was altered in the CPVT iPSC-CMs. β-adrenergic stimulation potentiated spontaneous Ca2+ waves and unduly frequent, large and prolonged Ca2+ sparks in CPVT compared with control iPSC-CMs, validating the disease phenotype. Pursuant to the patient's in vivo responses, nadolol treatment during β-adrenergic stimulation achieved negligible reduction of Ca2+ wave frequency and failed to rescue Ca2+ spark defects in CPVT iPSC-CMs. In contrast, flecainide reduced both frequency and amplitude of Ca2+ waves and restored the frequency, width and duration of Ca2+ sparks to baseline levels. By recapitulating the improved response of an individual with CPVT to flecainide compared with β-blocker therapy in vitro, these data provide new evidence that iPSC-CMs can capture basic components of patient-specific drug responses. PMID:27491078

  1. Imaging and measuring the rituximab-induced changes of mechanical properties in B-lymphoma cells using atomic force microscopy

    SciTech Connect

    Li, Mi; Liu, Lianqing; Xi, Ning; Wang, Yuechao; Dong, Zaili; Tabata, Osamu; Xiao, Xiubin; Zhang, Weijing

    2011-01-14

    Research highlights: {yields} Single B-lymphoma living cells were imaged by AFM with the assistance of microfabricated pillars. {yields} The apoptosis of B-lymphoma cells triggered by rituximab without cross-linking was observed by AO/EB double fluorescent staining. {yields} The B-lymphoma cells became dramatically softer after adding rituximab. -- Abstract: The topography and mechanical properties of single B-lymphoma cells have been investigated by atomic force microscopy (AFM). With the assistance of microfabricated patterned pillars, the surface topography and ultrastructure of single living B-lymphoma cell were visualized by AFM. The apoptosis of B-lymphoma cells induced by rituximab alone was observed by acridine orange/ethidium bromide (AO/EB) double fluorescent staining. The rituximab-induced changes of mechanical properties in B-lymphoma cells were measured dynamically and the results showed that B-lymphoma cells became dramatically softer after incubation with rituximab. These results can improve our understanding of rituximab'effect and will facilitate the further investigation of the underlying mechanisms.

  2. A novel mutation in the RYR2 gene leading to catecholaminergic polymorphic ventricular tachycardia and paroxysmal atrial fibrillation: dose-dependent arrhythmia-event suppression by β-blocker therapy.

    PubMed

    Kazemian, Pedram; Gollob, Michael H; Pantano, Alfredo; Oudit, Gavin Y

    2011-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a genetic condition that presents with exercise-induced polymorphic arrhythmias. We describe a case report of a 25-year-old woman who had a cardiac arrest due to ventricular fibrillation. Genetic analysis revealed a novel missense mutation in exon 90 of the ryanodine receptor (RyR2) gene resulting in substitution of arginine for serine at residue 4153 (S4153R). The patient received an implantable cardioverter-defibrillator and low-dose β-blocker therapy. She had recurrent polymorphic ventricular arrhythmias treated with appropriate cardioverter-defibrillator shocks and paroxysmal atrial fibrillation. Titration of β-blocker to a much higher dose suppressed further episodes of ventricular arrhythmia and paroxysmal atrial fibrillation, resulting in reduction in device therapies.

  3. Neutralization of (NK-cell-derived) B-cell activating factor by Belimumab restores sensitivity of chronic lymphoid leukemia cells to direct and Rituximab-induced NK lysis.

    PubMed

    Wild, J; Schmiedel, B J; Maurer, A; Raab, S; Prokop, L; Stevanović, S; Dörfel, D; Schneider, P; Salih, H R

    2015-08-01

    Natural killer (NK) cells are cytotoxic lymphocytes that substantially contribute to the therapeutic benefit of antitumor antibodies like Rituximab, a crucial component in the treatment of B-cell malignancies. In chronic lymphocytic leukemia (CLL), the ability of NK cells to lyse the malignant cells and to mediate antibody-dependent cellular cytotoxicity upon Fc receptor stimulation is compromised, but the underlying mechanisms are largely unclear. We report here that NK-cells activation-dependently produce the tumor necrosis factor family member 'B-cell activating factor' (BAFF) in soluble form with no detectable surface expression, also in response to Fc receptor triggering by therapeutic CD20-antibodies. BAFF in turn enhanced the metabolic activity of primary CLL cells and impaired direct and Rituximab-induced lysis of CLL cells without affecting NK reactivity per se. The neutralizing BAFF antibody Belimumab, which is approved for treatment of systemic lupus erythematosus, prevented the effects of BAFF on the metabolism of CLL cells and restored their susceptibility to direct and Rituximab-induced NK-cell killing in allogeneic and autologous experimental systems. Our findings unravel the involvement of BAFF in the resistance of CLL cells to NK-cell antitumor immunity and Rituximab treatment and point to a benefit of combinatory approaches employing BAFF-neutralizing drugs in B-cell malignancies.

  4. Progressive multifocal leukoencephalopathy secondary to rituximab-induced immunosuppression and the presence of John Cunningham virus: a case report and literature review.

    PubMed

    Kelly, Deirdre; Monaghan, Bernadette; McMahon, Eileen; Watson, Geoffrey; Kavanagh, Eoin; O'Rourke, Killian; McCaffrey, John; Carney, Desmond

    2016-09-01

    We present the case of a 60-year-old man who developed subacute neurologic changes, in the setting of stage III non-Hodgkin's follicular lymphoma, and was treated with induction chemotherapy, followed by a year of maintenance rituximab. Magnetic resonance imaging of the brain with gadolinium was pathognomonic for progressive multifocal leukoencephalopathy (PML). He was treated with sequential plasmapheresis and intravenous immunoglobulin with clinical improvement. A literature review of the diagnostic workup of rituximab-induced PML was undertaken. This case and the literature review demonstrate the important role of magnetic resonance imaging of the brain in diagnosis and follow-up of rituximab-induced PML. Specific radiologic features in combination with cerebrospinal fluid can be diagnostic and avoid the morbidity and mortality of a diagnostic brain biopsy. Plasmapheresis and intravenous immunoglobulin have a therapeutic role and demonstrate symptom improvement and disease control. Follow-up imaging in combination with clinical response is important in demonstrating a treatment response. PMID:27594961

  5. Antiarrhythmic Effects of Dantrolene in Patients with Catecholaminergic Polymorphic Ventricular Tachycardia and Replication of the Responses Using iPSC Models

    PubMed Central

    Vanninen, Sari; Paavola, Jere; Lahtinen, Annukka M.; Kontula, Kimmo; Aalto-Setälä, Katriina

    2015-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a highly malignant inherited arrhythmogenic disorder. Type 1 CPVT (CPVT1) is caused by cardiac ryanodine receptor (RyR2) gene mutations resulting in abnormal calcium release from sarcoplasmic reticulum. Dantrolene, an inhibitor of sarcoplasmic Ca2+ release, has been shown to rescue this abnormal Ca2+ release in vitro. We assessed the antiarrhythmic efficacy of dantrolene in six patients carrying various RyR2 mutations causing CPVT. The patients underwent exercise stress test before and after dantrolene infusion. Dantrolene reduced the number of premature ventricular complexes (PVCs) on average by 74% (range 33-97) in four patients with N-terminal or central mutations in the cytosolic region of the RyR2 protein, while dantrolene had no effect in two patients with mutations in or near the transmembrane domain. Induced pluripotent stem cells (iPSCs) were generated from all the patients and differentiated into spontaneously beating cardiomyocytes (CMs). The antiarrhythmic effect of dantrolene was studied in CMs after adrenaline stimulation by Ca2+ imaging. In iPSC derived CMs with RyR2 mutations in the N-terminal or central region, dantrolene suppressed the Ca2+ cycling abnormalities in 80% (range 65-97) of cells while with mutations in or near the transmembrane domain only in 23 or 32% of cells. In conclusion, we demonstrate that dantrolene given intravenously shows antiarrhythmic effects in a portion of CPVT1 patients and that iPSC derived CM models replicate these individual drug responses. These findings illustrate the potential of iPSC models to individualize drug therapy of inherited diseases. Trial Registration EudraCT Clinical Trial Registry 2012-005292-14 PMID:25955245

  6. A Missense Mutation in a Highly Conserved Region of CASQ2 Is Associated with Autosomal Recessive Catecholamine-Induced Polymorphic Ventricular Tachycardia in Bedouin Families from Israel

    PubMed Central

    Lahat, Hadas; Pras, Elon; Olender, Tsviya; Avidan, Nili; Ben-Asher, Edna; Man, Orna; Levy-Nissenbaum, Etgar; Khoury, Asad; Lorber, Avraham; Goldman, Boleslaw; Lancet, Doron; Eldar, Michael

    2001-01-01

    Catecholamine-induced polymorphic ventricular tachycardia (PVT) is characterized by episodes of syncope, seizures, or sudden death, in response to physical activity or emotional stress. Two modes of inheritance have been described: autosomal dominant and autosomal recessive. Mutations in the ryanodine receptor 2 gene (RYR2), which encodes a cardiac sarcoplasmic reticulum (SR) Ca2+-release channel, were recently shown to cause the autosomal dominant form of the disease. In the present report, we describe a missense mutation in a highly conserved region of the calsequestrin 2 gene (CASQ2) as the potential cause of the autosomal recessive form. The CASQ2 protein serves as the major Ca2+ reservoir within the SR of cardiac myocytes and is part of a protein complex that contains the ryanodine receptor. The mutation, which is in full segregation in seven Bedouin families affected by the disorder, converts a negatively charged aspartic acid into a positively charged histidine, in a highly negatively charged domain, and is likely to exert its deleterious effect by disrupting Ca2+ binding. PMID:11704930

  7. Patient-Specific Human Induced Pluripotent Stem Cell Model Assessed with Electrical Pacing Validates S107 as a Potential Therapeutic Agent for Catecholaminergic Polymorphic Ventricular Tachycardia

    PubMed Central

    Sasaki, Kenichi; Makiyama, Takeru; Yoshida, Yoshinori; Wuriyanghai, Yimin; Kamakura, Tsukasa; Nishiuchi, Suguru; Hayano, Mamoru; Harita, Takeshi; Yamamoto, Yuta; Kohjitani, Hirohiko; Hirose, Sayako; Chen, Jiarong; Kawamura, Mihoko; Ohno, Seiko; Itoh, Hideki; Takeuchi, Ayako; Matsuoka, Satoshi; Miura, Masaru; Sumitomo, Naokata; Horie, Minoru; Yamanaka, Shinya; Kimura, Takeshi

    2016-01-01

    Introduction Human induced pluripotent stem cells (hiPSCs) offer a unique opportunity for disease modeling. However, it is not invariably successful to recapitulate the disease phenotype because of the immaturity of hiPSC-derived cardiomyocytes (hiPSC-CMs). The purpose of this study was to establish and analyze iPSC-based model of catecholaminergic polymorphic ventricular tachycardia (CPVT), which is characterized by adrenergically mediated lethal arrhythmias, more precisely using electrical pacing that could promote the development of new pharmacotherapies. Method and Results We generated hiPSCs from a 37-year-old CPVT patient and differentiated them into cardiomyocytes. Under spontaneous beating conditions, no significant difference was found in the timing irregularity of spontaneous Ca2+ transients between control- and CPVT-hiPSC-CMs. Using Ca2+ imaging at 1 Hz electrical field stimulation, isoproterenol induced an abnormal diastolic Ca2+ increase more frequently in CPVT- than in control-hiPSC-CMs (control 12% vs. CPVT 43%, p<0.05). Action potential recordings of spontaneous beating hiPSC-CMs revealed no significant difference in the frequency of delayed afterdepolarizations (DADs) between control and CPVT cells. After isoproterenol application with pacing at 1 Hz, 87.5% of CPVT-hiPSC-CMs developed DADs, compared to 30% of control-hiPSC-CMs (p<0.05). Pre-incubation with 10 μM S107, which stabilizes the closed state of the ryanodine receptor 2, significantly decreased the percentage of CPVT-hiPSC-CMs presenting DADs to 25% (p<0.05). Conclusions We recapitulated the electrophysiological features of CPVT-derived hiPSC-CMs using electrical pacing. The development of DADs in the presence of isoproterenol was significantly suppressed by S107. Our model provides a promising platform to study disease mechanisms and screen drugs. PMID:27764147

  8. Prevalence of the angiotensin I converting enzyme insertion/deletion polymorphism, plasma angiotensin converting enzyme activity, and left ventricular mass in a normotensive Chilean population.

    PubMed

    Jalil, J E; Piddo, A M; Cordova, S; Chamorro, G; Braun, S; Jalil, R; Vega, J; Jadue'P, L; Lavandero, S; Lastra, P

    1999-07-01

    The aim of this study was to estimate the prevalence of the different alleles of the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and associated plasma ACE activity, as well as cardiac echocardiographic structure, in a healthy Chilean population. We selected 117 healthy normotensive subjects (aged 45 to 60 years, middle socioeconomic status, nonobese, and nondiabetic) from a population-based study concerning the prevalence of risk factors for chronic diseases (Conjunto de Acciones Para la Reducción Multifactorial de las Enfermedades no Transmisibles [CARMEN]). The frequencies of the I and D alleles were 0.57 and 0.43, respectively. Mean plasma ACE activity was 15.3 +/- 3.9 U/mL. Compared with subjects with the II genotype, plasma ACE activity was significantly higher in subjects with the ID and DD genotypes with no difference between them. No correlation was observed between blood pressure and plasma ACE activity. Among the three different genotypes there was no difference in left ventricular (LV) dimensions or in LV mass. No correlation between plasma ACE activity and LV mass was observed for either gender or different genotypes. Multivariate linear regression analysis using LV mass and LV mass index as dependent variables showed independent effects (P < .05) for gender (higher LV mass in men) and diastolic blood pressure, but not for the DD genotype. In conclusion, in this population, the presence of the D allele on the ACE gene determined higher circulating ACE activity. However, in this normotensive healthy population, male gender and diastolic blood pressure, but not the presence of the D allele, were associated with increased LV mass.

  9. Ca2+ signaling in human induced pluripotent stem cell-derived cardiomyocytes (iPS-CM) from normal and catecholaminergic polymorphic ventricular tachycardia (CPVT)-afflicted subjects.

    PubMed

    Zhang, X-H; Haviland, S; Wei, H; Sarić, T; Fatima, A; Hescheler, J; Cleemann, L; Morad, M

    2013-08-01

    Derivation of cardiomyocytes from induced pluripotent stem cells (iPS-CMs) allowed us to probe the Ca(2+)-signaling parameters of human iPS-CMs from healthy- and catecholaminergic polymorphic ventricular tachycardia (CPVT1)-afflicted individuals carrying a novel point mutation p.F2483I in ryanodine receptors (RyR2). iPS-CMs were dissociated on day 30-40 of differentiation and patch-clamped within 3-6 days. Calcium currents (ICa) averaged ∼8pA/pF in control and mutant iPS-CMs. ICa-induced Ca(2+)-transients in control and mutant cells had bell-shaped voltage-dependence similar to that of ICa, consistent with Ca(2+)-induced Ca(2+)-release (CICR) mechanism. The ratio of ICa-activated to caffeine-triggered Ca(2+)-transients was ∼0.3 in both cell types. Caffeine-induced Ca(2+)-transients generated significantly smaller Na(+)-Ca(2+) exchanger current (INCX) in mutant cells, reflecting their smaller Ca(2+)-stores. The gain of CICR was voltage-dependent as in adult cardiomyocytes. Adrenergic agonists enhanced ICa, but differentially altered the CICR gain, diastolic Ca(2+), and Ca(2+)-sparks in mutant cells. The mutant cells, when Ca(2+)-overloaded, showed longer and wandering Ca(2+)-sparks that activated adjoining release sites, had larger CICR gain at -30mV yet smaller Ca(2+)-stores. We conclude that control and mutant iPS-CMs express the adult cardiomyocyte Ca(2+)-signaling phenotype. RyR2 F2483I mutant myocytes have aberrant unitary Ca(2+)-signaling, smaller Ca(2+)-stores, higher CICR gains, and sensitized adrenergic regulation, consistent with functionally altered Ca(2+)-release profile of CPVT syndrome. PMID:23684427

  10. Ventricular assist device

    MedlinePlus

    VAD; RVAD; LVAD; BVAD; Right ventricular assist device; Left ventricular assist device; Biventricular assist device; Heart pump; Left ventricular assist system; LVAS; Implantable ventricular assist device

  11. Ventricular arrhythmias.

    PubMed Central

    Kavanagh, K M; Wyse, D G

    1988-01-01

    Sudden cardiac death claims thousands of Canadians annually. Ventricular tachycardia and fibrillation account for up to 85% of these deaths. Identifying the patients at risk remains a major challenge. Those who have recurrent ventricular tachycardia or have been resuscitated from ventricular fibrillation are generally considered to be at highest risk. Although ventricular premature beats in the absence of previous ventricular tachycardia or fibrillation are not helpful in identifying such patients in most cases, they can indicate increased risk for sudden cardiac death in the presence of a structural cardiac abnormality, particularly recent myocardial infarction; however, the need for treatment in such cases is speculative and is being investigated. Treatment is mandatory for survivors of an episode of ventricular fibrillation and those with recurrent sustained ventricular tachycardia or torsade de pointes ventricular tachycardia. The approach to management is either invasive or noninvasive. Selection of an antiarrhythmic agent is facilitated by knowledge of some basic electrophysiologic features of the heart and of the classification of antiarrhythmic drugs. However, drug therapy has to be individualized on the basis of efficacy, left ventricular function and adverse effects or potential adverse effects of the drug. Amiodarone therapy or nonpharmacologic therapy should be considered if a suitable antiarrhythmic agent cannot be found. PMID:3284626

  12. S4153R is a gain-of-function mutation in the cardiac Ca(2+) release channel ryanodine receptor associated with catecholaminergic polymorphic ventricular tachycardia and paroxysmal atrial fibrillation.

    PubMed

    Zhabyeyev, Pavel; Hiess, Florian; Wang, Ruiwu; Liu, Yingjie; Wayne Chen, S R; Oudit, Gavin Y

    2013-08-01

    Mutations in ryanodine receptor 2 (RYR2) gene can cause catecholaminergic polymorphic ventricular tachycardia (CPVT). The novel RYR2-S4153R mutation has been implicated as a cause of CPVT and atrial fibrillation. The mutation has been functionally characterized via store-overload-induced Ca(2+) release (SOICR) and tritium-labelled ryanodine ([(3)H]ryanodine) binding assays. The S4153R mutation enhanced propensity for spontaneous Ca(2+) release and reduced SOICR threshold but did not alter Ca(2+) activation of [(3)H]ryanodine binding, a common feature of other CPVT gain-of-function RYR2 mutations. We conclude that the S4153R mutation is a gain-of-function RYR2 mutation associated with a clinical phenotype characterized by both CPVT and atrial fibrillation.

  13. Anger and ventricular arrhythmias

    PubMed Central

    Lampert, Rachel

    2011-01-01

    Purpose of review Although anecdotal evidence has long suggested links between emotion and ventricular arrhythmia, more recent studies have prospectively demonstrated the arrhythmogenic effects of anger, as well as mechanisms underlying these effects. Recent findings Epidemiological studies reveal that psychological stress increases sudden death, as well as arrhythmias, in patients with implantable cardioverter-defibrillators, in populations during emotionally devastating disasters such as earthquake or war. Diary-based studies confirm that anger and other negative emotions can trigger potentially lethal ventricular arrhythmias. Anger alters electrophysiological properties of the myocardium, including T-wave alternans, a measure of heterogeneity of repolarization, suggesting one mechanistic link between emotion and arrhythmia. Pilot studies of behavioral interventions have shown promise in decreasing arrhythmias in patients with implantable cardioverter-defibrillators. Summary Anger and other strong emotions can trigger polymorphic, potentially life-threatening ventricular arrhythmias in vulnerable patients. Through autonomic changes including increased sympathetic activity and vagal withdrawal, anger leads to increases in heterogeneity of repolarization as measured by T-wave alternans, known to be associated with arrhythmogenesis, as well as increasing inducibility of arrhythmia. Further delineation of mechanisms linking anger and arrhythmia, and of approaches to decrease the detrimental effects of anger and other negative emotions on arrhythmogenesis, are important areas of future investigation. PMID:19864944

  14. Bone Marrow Stromal Cells Protect Lymphoma B-cells from Rituximab-Induced Apoptosis and Targeting Integrin alfa-4-beta-1 (VLA-4) with Natalizumab can Overcome this Resistance

    PubMed Central

    Mraz, Marek; Zent, Clive S.; Church, Amy K.; Jelinek, Diane F.; Wu, Xiaosheng; Pospisilova, Sarka; Ansell, Stephen M.; Novak, Anne J.; Kay, Neil E.; Witzig, Thomas E.; Nowakowski, Grzegorz S.

    2011-01-01

    Rituximab improves the outcome of patients with non-Hodgkin lymphoma, but does not completely eradicate residual B-cell populations in the microenvironment of the bone marrow and lymph nodes. Adhesion to stromal cells can protect B-cells from apoptosis induced by chemotherapy drugs (cell adhesion-mediated drug resistance; CAM-DR). A similar mechanism of resistance to rituximab has not, to our knowledge, been described. We tested the hypothesis that the microenvironment protects malignant B-cells from rituximab-induced apoptosis, and that blocking these interactions with natalizumab, an antibody targeting VLA-4 (integrin alfa-4-beta-1/CD49d), can overcome this protection. VLA-4 is an adhesion molecule constitutively expressed on malignant B-cells and is important for pro-survival signalling in the bone marrow and lymph node microenvironment. The human bone marrow stromal cell line HS-5 was shown to strongly protect B-cell lymphoma cells from rituximab cytotoxicity, suggesting the existence of a stromal cell adhesion-mediated antibody resistance (CAM-AR) mechanism analogous to CAM-DR. Natalizumab decreased B-lymphocyte adherence to fibronectin by 75-95% and partially overcame stromal protection against rituximab and cytotoxic drugs. These pre-clinical findings suggest that the addition of stromal adhesion-disruptive drugs to rituximab-containing therapy could improve treatment efficacy. PMID:21749361

  15. Arrhythmogenic Right Ventricular Dysplasia

    MedlinePlus

    MENU Return to Web version Arrhythmogenic Right Ventricular Dysplasia Overview What is arrhythmogenic right ventricular dysplasia? Arrhythmogenic right ventricular dysplasia (say: “uh-rith-mo-jen-ic right ven-trick- ...

  16. Ventricular septal defect (image)

    MedlinePlus

    Ventricular septal defect is a congenital defect of the heart, that occurs as an abnormal opening in ... wall that separates the right and left ventricles. Ventricular septal defect may also be associated with other ...

  17. Percutaneous left ventricular restoration.

    PubMed

    Ige, Mobolaji; Al-Kindi, Sadeer G; Attizzani, Guilherme; Costa, Marco; Oliveira, Guilherme H

    2015-04-01

    The ventricular partitioning device known as Parachute is the first and only percutaneously implantable device aimed at restoration of normal left ventricular geometry in humans. Since its conception, this technology has undergone extensive animal and human testing, with proved feasibility and safety, and is currently being studied in a pivotal randomized clinical trial. This article discusses ventricular remodeling and therapies attempted in the past, details the components of the ventricular partitioning device, describes the implanting technique, and reviews the most current experience of this device in humans.

  18. Percutaneous left ventricular restoration.

    PubMed

    Ige, Mobolaji; Al-Kindi, Sadeer G; Attizzani, Guilherme; Costa, Marco; Oliveira, Guilherme H

    2015-04-01

    The ventricular partitioning device known as Parachute is the first and only percutaneously implantable device aimed at restoration of normal left ventricular geometry in humans. Since its conception, this technology has undergone extensive animal and human testing, with proved feasibility and safety, and is currently being studied in a pivotal randomized clinical trial. This article discusses ventricular remodeling and therapies attempted in the past, details the components of the ventricular partitioning device, describes the implanting technique, and reviews the most current experience of this device in humans. PMID:25834974

  19. Ventricular tachycardia in acromegaly.

    PubMed

    Arias, Miguel A; Pachón, Marta; Rodríguez-Padial, Luis

    2011-02-01

    Cases of sudden cardiac death have been reported in patients with acromegaly. Malignant ventricular arrhythmias may play an important role in this fatal complication, but the exact mechanisms are not well understood. We report on an acromegalic patient presenting with documented recurrent syncopal ventricular tachycardia.

  20. 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.

  1. Right ventricular assistance for experimental right ventricular dysfunction.

    PubMed

    Jett, G K; Applebaum, R E; Clark, R E

    1986-08-01

    Right ventricular dysfunction frequently occurs in patients undergoing correction of congenital cardiac defects, as well as in other clinical settings. The purpose of the present study was to surgically induce right ventricular dysfunction and then provide circulatory support with a right ventricular assist device. Right ventricular hypertrophy was created in 13 neonatal lambs by pulmonary artery banding. Right ventricular dysfunction was produced in all animals by performing a right ventriculotomy with the animal supported by cardiopulmonary bypass. In four unassisted animals the circulation failed after separation from bypass. Seven experimental animals underwent the insertion of a pneumatically activated ventricular assist device between the proximal pulmonary artery and the right ventricular apex. Periods with the right ventricular assist device on and off in each animal were compared. The right ventricular assist device increased cardiac output from 0.72 +/- 0.15 to 2.24 +/- 0.23 L/min (p less than 0.0002), increased left atrial pressure from 7 +/- 1 to 11 +/- 1 mm Hg (p less than 0.0005), and increased aortic systolic pressure from 53 +/- 9 to 85 +/- 9 mm Hg (p less than 0.0001). Right ventricular assistance significantly reduced the right ventricular end-diastolic pressure from 19 +/- 3 to 12 +/- 1 mm Hg (p less than 0.0001). Pulmonary artery peak pressure distal to the band increased from 27 +/- 3 to 52 +/- 5 mm Hg (p less than 0.0001). The results indicate that right ventricular dysfunction can be produced by a vertical cardiotomy in a hypertrophied right ventricle with persistent outflow tract obstruction. Right ventricular dysfunction can be effectively reversed by a right ventricular assist device, which may prove clinically useful in managing patients with refractory right ventricular failure.

  2. Right Ventricular Myxoma.

    PubMed

    Vadivelmurugan, S; Senthamarai; Sakthimohan; Janarthanan; Balanayagam; Anand, Vijay; Venkateswaran, K J; Ramkumar; Selvaraj

    2015-10-01

    We report a case of 30 year female who presented with complaints of intermittent chest pain and breathlessness for 8 months, Diagnosed to have right ventricular mass protruding into main pulmonary artery during each systole. The mass was completely excised. Histopathological examination showed myxoma. PMID:27608701

  3. 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.

  4. [Ventricular septal perforation].

    PubMed

    Ohno, Nobuhisa; Komeda, Masaharu

    2004-07-01

    As a mechanical complication of acute myocardial infarction, ventricular septal perforation (VSP) occurs mostly within 1 week after infarction. Although incidence of the disease is only 1-2% of transmural infarction, patients are into serious condition progressively once it happens. Even if patients were treated medically under intensive care protocol, they would almost always present congestive heart failure due to massive volume overload. Hence VSP should be treated surgically as soon as possible after its onset. We believe that infarct exclusion technique is standard procedure of surgical treatment, because it is relatively simple, makes less bleeding and gives minimal damage to right ventricle. Acute mortality has come down to 10-20% after introduction of this procedure. Cardiogenic shock before surgery, severe right heart failure and high age are important predictors of death. It is still difficult to save patients who are in severe cardiogenic shock with very low ventricular function. New treatments such as ventricular assist device, heart transplantation and regeneration therapy are waited for this high risk group of patients.

  5. Significance of postshunt ventricular asymmetries.

    PubMed

    Linder, M; Diehl, J T; Sklar, F H

    1981-08-01

    Ventricular asymmetries after shunt surgery were studied. Right and left ventricular areas from pre-and postoperative computerized tomography scans were measured with a computer digitizing technique, and the respective areas were expressed as a ratio. Measurements were made from the scans of 15 hydrocephalic children selected at random. Ages at surgery ranged from 1 to 101 weeks. The results indicate a significantly greater decrease in ventricular size on the side of the ventricular shunt catheter. Multiple regression analysis showed no relationship between the magnitude of change in ventricular size and either the patients' age orn the time intervals between surgery and follow-up scans. Possible mechanisms for these postshunt ventricular asymmetries are discussed.

  6. Postpartal right ventricular thrombosis.

    PubMed

    Velicki, Lazar; Milosavljević, Aleksandar; Majin, Marijan; Vujin, Bojan; Kovacević, Pavle

    2008-11-01

    The discovery of an intracardial mass in patients presents a serious diagnostic dilemma. The differential diagnosis of this condition may seem abundant, but myxomas and intracardial thrombosis are the most frequent diagnoses. A connection between pregnancy and the presence of thrombosis has been documented frequently. Normal pregnancy leads to changes of the coagulative and fibrinolytic status toward a hypercoagulable condition which has its own physiological justification (the risk of blood loss decreases during labor). The case of a patient suffering from postpartal right ventricular thrombosis, which was successfully resolved by surgery as described in this contribution, demonstrates the value of a multidisciplinary approach.

  7. Overlapping left ventricular restoration.

    PubMed

    Matsui, Yoshiro

    2009-06-01

    Cardiac transplantation, a final option of treatment for refractory heart failure, has not been a standard procedure in Japan especially, mainly because of the shortage of donors. However, surgical methods to restore native heart function, such as surgical ventricular restoration (SVR), are often effective for these cases. The Dor procedure has been used for ischemic cardiomyopathy cases presenting with broad akinetic segments. This is a fine method to exclude the scarred septum and to reduce the intraventricular cavity by encircling purse-string suture, but it may produce a postoperative spherical ventricular shape as a result of endoventricular patch repair. Also, partial left ventriculectomy is not recommended for non-ischemic dilated cardiomyopathy cases for now. A modification of these SVR and surgical approaches to functional mitral regurgitation has been named "overlapping ventriculoplasty" without endoventricular patch and resection of viable cardiac muscle, and "mitral complex reconstruction", which consists of mitral annuloplasty, papillary muscle approximation, and suspension. Although the long-term prognosis of these procedures is undetermined, they could be an important option, at least as an alternative bridge to transplantation. This review will describe the concepts and some technical aspects of these procedures for the end-stage heart. PMID:19474505

  8. 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

  9. Mapping and ablation of trigger premature ventricular contractions in a case of electrical storm associated with ischemic cardiomyopathy.

    PubMed

    Okada, Taro; Yamada, Takumi; Murakami, Yoshimasa; Yoshida, Naoki; Ninomiya, Yuuichi; Toyama, Junji

    2007-03-01

    We report a case of polymorphic ventricular tachycardia and ventricular fibrillation (PVT/VF) storm associated with ischemic cardiomyopathy (ICM). The electrocardiogram (ECG) monitor revealed frequent premature ventricular contractions (PVCs) initiated PVT/VF. Electroanatomic mapping revealed the plausible origins of PVCs were located in the scar border zone at the posterior septum of the left ventricle. Purkinje-like potentials (PLPs) always preceded PVCs and a decremental property for the PLPs and infarcted myocardium junction was observed. Ablation at these sites eliminated both PVCs and PVT/VF.

  10. Right ventricular apex pacing: is it obsolete?

    PubMed

    Sanaa, Islem; Franceschi, Frédéric; Prevot, Sébastien; Bastard, Emilie; Deharo, Jean-Claude

    2009-02-01

    Clinical trials in patients with pacemakers for sinus node dysfunction or atrioventricular block have highlighted the fact that desynchronization of ventricular contraction induced by right ventricular apical pacing is associated with long-term morbidity and mortality. These clinical data confirm pathophysiological results indicating that right ventricular apical pacing causes abnormal ventricular contraction, reduces pump function and leads to myocardial hypertrophy and ultrastructural abnormalities. In this manuscript, we discuss the clinical evidence for the adverse and beneficial effects of various right ventricular pacing sites, left ventricular pacing sites and biventricular pacing. We also propose a decisional algorithm for pacing modalities, based on atrioventricular conduction, left ventricular function and expected lifespan. PMID:19303581

  11. Facts about Ventricular Septal Defect

    MedlinePlus

    ... The size of the ventricular septal defect will influence what symptoms, if any, are present, and whether ... this image. Close Information For... Media Policy Makers Language: English Español (Spanish) File Formats Help: How do ...

  12. Ibrutinib and rituximab induced rapid response in refractory Richter syndrome.

    PubMed

    Lamar, Zanetta; Kennedy, LeAnne; Kennedy, Brooke; Lynch, Mary; Goad, Amanda; Hurd, David; McIver, Zachariah

    2015-07-01

    We report a 53-year-old man diagnosed with Richter syndrome. He was heavily pretreated and was refractory to prior therapy. He received rituximab and ibrutinib, and achieved a significant response after 1 month of therapy. Our case illustrates the importance of investigation of rituximab and ibrutinib in Richter's syndrome.

  13. Rituximab induces Interleukin-6 production by human B cells

    PubMed Central

    Jones, Jonathan D.; Hamilton, B. JoNell; Skopelja, Sladjana; Rigby, William F. C.

    2014-01-01

    Objective Rituximab (RTX), an anti-CD20 monoclonal antibody, is highly effective in the treatment of several autoimmune diseases. The mechanism by which RTX treatment improves Rheumatoid Arthritis and ANCA-Associated Vasculitis is not easily related to B cell depletion. We have shown that RTX mediates a rapid stripping of CD20 and CD19 from the human B cell through a process known as trogocytosis. We hypothesized that changes in B cell phenotype resulting from trogocytosis would diminish the ability of B cells to promote autoimmune disease. Methods Human PBMC were cultured with RTX under conditions that permitted trogocytosis. Changes in B cell phenotype and cytokine production were measured under basal and activated (IL-4/anti-CD40) conditions. The effects of RTX were characterized for their requirements for FcγR and Fc-dependent interactions. Results Trogocytosis induced a marked loss of surface CD19, IgD, CD40 and BR3, but did not alter induction of CD86 expression on purified B cells by IL-4/anti-CD40 treatment. Unexpectedly, RTX-dependent trogocytosis of normal human B cells in vitro led to a rapid upregulation of IL-6 production, with no effect on TNFα, IL-1β, INFγ, or IL-10 production. This effect was Fc-dependent and required the presence of an FcγR bearing cell. This effect involved the release of pre-formed intracellular IL-6 protein as well as marked increases in IL-6 mRNA levels. Conclusion RTX mediated trogocytosis of B cells in vitro results in acute production and release of IL-6. The nature of this effect and its relationship to acute infusion reactions seen with RTX administration remain to be determined. PMID:25080282

  14. Catheter ablation of a monofocal premature ventricular complex triggering idiopathic ventricular fibrillation.

    PubMed

    Takatsuki, S; Mitamura, H; Ogawa, S

    2001-07-01

    A 62 year old man was admitted for evaluation of recurrent episodes of syncope. A surface ECG showed frequent repetitive premature ventricular complexes of right ventricular outflow tract origin. Ventricular fibrillation was inducible by programmed electrical stimulation but otherwise cardiac evaluation was unremarkable. A diagnosis of idiopathic ventricular fibrillation was made and an implantable cardioverter-defibrillator (ICD) was installed. However, spontaneous ventricular fibrillation recurred, requiring repeated ICD discharges. The ventricular fibrillation was reproducibly triggered by a single premature ventricular complex with a specific QRS morphology. Radiofrequency catheter ablation was carried out to eradicate this complex. No ventricular fibrillation has developed after this procedure, and the patient does not require drug treatment.

  15. Ventricular Tachycardia Associated Syncope in a Patient of Variant Angina without Chest Pain

    PubMed Central

    Kim, Soo Jin; Juong, Ji Young

    2016-01-01

    A 68-year-old man was admitted for a syncope workup. After routine evaluation, he was diagnosed with syncope of an unknown cause and was discharged from the hospital. He was readmitted due to dizziness. On repeated Holter monitoring, polymorphic ventricular tachycardia was detected during syncope. We performed intracoronary ergonovine provocation test; severe coronary spasm was induced at 70% stenosis of the proximal left anterior descending artery. The patient was treated with percutaneous coronary intervention. We present a rare case of syncope induced by ventricular arrhythmia in a patient with variant angina without chest pain. PMID:26798392

  16. 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

  17. Molecular mechanisms of ventricular hypoplasia.

    PubMed

    Srivastava, D; Gottlieb, P D; Olson, E N

    2002-01-01

    We have established the beginnings of a road map to understand how ventricular cells become specified, differentiate, and expand into a functional cardiac chamber (Fig. 5). The transcriptional networks described here provide clear evidence that disruption of pathways affecting ventricular growth could be the underlying etiology in a subset of children born with malformation of the right or left ventricle. As we learn details of the precise mechanisms through which the critical factors function, the challenge will lie in devising innovative methods to augment or modify the effects of gene mutations on ventricular development. Because most congenital heart disease likely occurs in a setting of heterozygous, predisposing mutations of one or more genes, modulation of activity of critical pathways in a preventive fashion may be useful in averting disease in genetically susceptible individuals. PMID:12858532

  18. 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

  19. Left Ventricular Assist Devices

    PubMed Central

    2004-01-01

    Executive Summary Objective The objective of this health technology policy assessment was to determine the effectiveness and cost-effectiveness of using implantable ventricular assist devices in the treatment of end-stage heart failure. Heart Failure Heart failure is a complex syndrome that impairs the ability of the heart to maintain adequate blood circulation, resulting in multiorgan abnormalities and, eventually, death. In the period of 1994 to 1997, 38,702 individuals in Ontario had a first hospital admission for heart failure. Despite reported improvement in survival, the five-year mortality rate for heart failure is about 50%. For patients with end-stage heart failure that does not respond to medical therapy, surgical treatment or traditional circulatory assist devices, heart transplantation (in appropriate patients) is the only treatment that provides significant patient benefit. Heart Transplant in Ontario With a shortage in the supply of donor hearts, patients are waiting longer for a heart transplant and may die before a donor heart is available. From 1999 to 2003, 55 to 74 people received a heart transplant in Ontario each year. Another 12 to 21 people died while waiting for a suitable donor heart. Of these, 1 to 5 deaths occurred in people under 18 years old. The rate-limiting factor in heart transplant is the supply of donor hearts. Without an increase in available donor hearts, attempts at prolonging the life of some patients on the transplant wait list could have a harmful effect on other patients that are being pushed down the waiting list (knock on effect). LVAD Technology Ventricular assist devices [VADs] have been developed to provide circulatory assistance to patients with end-stage heart failure. These are small pumps that usually assist the damaged left ventricle [LVADs] and may be situated within the body (intracorporeal] or outside the body [extracorporeal). Some of these devices were designed for use in the right ventricle [RVAD] or both

  20. [Fulguration of extrasystolic ventricular focus].

    PubMed

    Velázquez Rodríguez, E; Rosas, F; Frank, R; Fontaine, G; Tonet, J; Lascault, G; Gallais, Y

    1995-01-01

    A case is presented of symptomatic premature ventricular contractions refractory to drug therapy with right bundle branch block QRS morphology and left axis deviation in a 68-year-old female without structural heart disease. Endocardial mapping localized the extrasystolic focus at meso-inferoapical region of the left ventricular septum suggesting an origin from the Purkinje network of the left posterior fascicle. Catheter ablation with direct-current energy abolished extrasystolic complexes, without complications. The patient remained asymptomatic over a follow-up of 3 months. PMID:7543744

  1. Noncompaction of the ventricular myocardium associated with mitral regurgitation and preserved ventricular systolic function.

    PubMed

    Ali, Sulafa Khalid M; Omran, Ahmed S; Najm, Hani; Godman, Michael J

    2004-01-01

    Noncompaction of the ventricular myocardium is an embryonic cardiomyopathy that is increasingly being recognized. Mitral regurgitation, when present, is usually a result of the associated left ventricular systolic dysfunction. We report 4 patients with noncompaction of the ventricular myocardium in whom ventricular systolic function was preserved. Mitral regurgitation was associated with changes in the mitral valve leaflets and an abnormal coaptation pattern. This association of noncompaction of the ventricular myocardium with mitral regurgitation has not, to our knowledge, been reported.

  2. 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.

  3. Ventricular arrhythmias: state of the art.

    PubMed

    Schleifer, J William; Srivathsan, Komandoor

    2013-11-01

    The management of ventricular tachycardia and ventricular fibrillation in the cardiac intensive care unit can be complex. These arrhythmias have many triggers, including ischemia, sympathetic stimulation, and medication toxicities, as well as many different substrates, ranging from ischemic and nonischemic cardiomyopathies to rare genetic conditions such as Brugada syndrome and long QT syndrome. Different settings, such as congenital heart disease, postoperative ventricular arrhythmias, and ventricular assist devices, increase the complexity of management. This article reviews the variety of situations and cardiac conditions that give rise to ventricular arrhythmias, focusing on inpatient management strategies.

  4. Congenital left ventricular apical aneurysm presenting as ventricular tachycardia.

    PubMed

    Amado, José; Marques, Nuno; Candeias, Rui; Gago, Paula; de Jesus, Ilídio

    2016-10-01

    The authors present the case of a 34-year-old male patient seen in our department due to palpitations. On the electrocardiogram monomorphic ventricular tachycardia (VT) was documented, treated successfully with amiodarone. The subsequent study revealed a normal echocardiogram and an apical aneurysm of the left ventricle on magnetic resonance imaging, confirmed by computed tomography coronary angiography that also excluded coronary disease. He underwent an electrophysiological study to determine the origin of the VT and to perform catheter ablation using electroanatomical mapping. VT was induced and radiofrequency applications were performed in the left ventricular aneurysm area. VT was no longer inducible, with acute success. Despite this it was decided to implant a subcutaneous implantable cardioverter-defibrillator (ICD). Eight months after the ablation the patient was admitted again due to VT, treated by the ICD.

  5. Mechanics of left ventricular aneurysm.

    PubMed

    Radhakrishnan, S; Ghista, D N; Jayaraman, G

    1986-01-01

    When a coronary artery is significantly occluded, the left ventricular myocardial segment, which is perfused by that coronary artery, will become ischaemic and even irreversibly infarcted. An acute infarct has very low stiffness and if it involves the entire wall there is a risk of rupture; however, in the absence of such a critical situation, fibrous tissue is laid into the infarcted myocardial segment. Such an infarcted fibrotic myocardial segment will not be able to contract, and so generate tensile stress. The surrounding intact myocardium will contract and generate wall stress, thereby developing a high intra-chamber systolic pressure; the chronically infarcted and fibrotic segment will have to sustain this high chamber pressure. Its loss of contractility and the resulting reduced systolic stiffness relative to the intact segment, will cause it to deform into a bulge; this is an aneurysm. When a left ventricular chamber with an aneurysm contracts during the systolic phase, some blood also goes into the aneurysm, and this decreases the stroke volume; since the aneurysm wall is passive, stagnant blood flow prevails in the aneurysm itself, which in turn can give rise to the formation of a mural thrombus. These serious consequences provide a justification for the analysis of an infarcted left ventricular chamber, in order to predict the size of the aneurysmic bulge. Such an analysis is presented in this paper. To determine the left ventricular wall deformation, and the stress arising from infarction of a wall segment (which leads to a ventricular aneurysm) the left ventricle is modelled here as a pressurized ellipsoidal shell. Deformations of infarcted wall segments are computed for several damaged wall-thicknesses in left ventricles of different shapes. The analysis involves a derivation of equations for wall-stress equilibrium with the chamber pressure, and myocardial incompressibility before and after infarct formation. The equations are solved by the Newton

  6. Effect of magnesium sulfate on ventricular refractoriness and its efficacy for torsade de pointes.

    PubMed

    Bando, S; Yamamoto, H; Nishikado, A; Hamai, K; Fujino, K; Nakaya, Y; Shinohara, A

    1990-12-01

    The effect of magnesium sulfate on ventricular refractoriness and its efficacy for torsade de pointes (TdP) were studied in nineteen dogs. After the administration of quinidine sulfate (30 mg/kg), TdP was induced by ventricular pacing in ten of 19 dogs (52.6%), polymorphic ventricular tachycardia in seven (36.8%), ventricular fibrillation in two (10.5%). Quinidine sulfate caused significant increases in QTc interval, ventricular effective refractory period (ERP) and dispersion of ERP(dERP), and decrease in ERP/QT. Magnesium sulfate significantly increased ERP (p less than 0.01), but it did not change QT interval, resulting in significant increasing of ERP/QT (0.41 +/- 0.05 to 0.61 +/- 0.05, p less than 0.01). It decreased dERP but not significantly. Magnesium sulfate prevented the induction of TdP in eight of 10 dogs (80.0%) (30 mg/kg in four and 60 mg/kg in four). In conclusion, magnesium sulfate has value as first aid therapy for drug-induced TdP. If patients have ischemic heart disease or hypertension, we recommend infusion of magnesium for the initial therapy of TdP. PMID:2094063

  7. Ventricular assist devices: initial orientation.

    PubMed

    Schweiger, Martin; Dave, Hitendu; Lemme, Frithjof; Romanchenko, Olga; Hofmann, Michael; Hübler, Michael

    2013-08-01

    Ventricular assist device (VAD) technology has come from large pulsatile-flow devices with a high rate of technical malfunctions to small continuous flow (cf) devices. Mechanical circulatory support (MCS) systems may be used as short-, mid- or long-term support. Especially if mid- or long-term support is anticipated left VADs (LVADs) have been reported with excellent one and two year survival rates and improved quality of life (QoL). Timing of implantation, patient selection, assessing function of the right ventricular and surgical considerations regarding surgical access side, valve pathology and exit side of the percutaneous lead remain crucial issues for the outcome. In contrast VADs designed for children especially for all age groups, are still underrepresented but increased experience with existing pediatric VADs as well as introduction of second and third generation VADs into in the pediatric age group, offer new perspectives.

  8. Ventricular assist devices: initial orientation

    PubMed Central

    Dave, Hitendu; Lemme, Frithjof; Romanchenko, Olga; Hofmann, Michael; Hübler, Michael

    2013-01-01

    Ventricular assist device (VAD) technology has come from large pulsatile-flow devices with a high rate of technical malfunctions to small continuous flow (cf) devices. Mechanical circulatory support (MCS) systems may be used as short-, mid- or long-term support. Especially if mid- or long-term support is anticipated left VADs (LVADs) have been reported with excellent one and two year survival rates and improved quality of life (QoL). Timing of implantation, patient selection, assessing function of the right ventricular and surgical considerations regarding surgical access side, valve pathology and exit side of the percutaneous lead remain crucial issues for the outcome. In contrast VADs designed for children especially for all age groups, are still underrepresented but increased experience with existing pediatric VADs as well as introduction of second and third generation VADs into in the pediatric age group, offer new perspectives. PMID:23991317

  9. Ventricular hypertrophy--physiological mechanisms.

    PubMed

    Vaughan Williams, E M

    1986-01-01

    Adult cardiac myocytes are incapable of mitosis. Dead cells are replaced by connective tissue so that after myocardial infarction (MI), function can only be restored by compensatory hypertrophy of the surviving myocardium. In physiological hypertrophy in response to exercise, high altitude, or mild hypertension, additional myoplasm expands cell diameter in an orderly fashion; Z-lines are in register and the normal ratio of volume densities of contractile elements, mitochondria, and capillaries is conserved. In hypertrophy induced by aortic or pulmonary artery banding or by experimental or congenital hypertension, the borderline between physiological and pathological hypertrophy may be crossed, causing disorganization of fibers and an unfavourable contractile element to capillary ratio. There was, therefore, a need for a graded model of hypertrophy, which involves simulating an altitude of 6,000 m at sea level by supplying rabbits with appropriate nitrogen/oxygen mixtures. In this environment, 50% right ventricular hypertrophy can be achieved without alteration of left ventricular weight or hematocrit. Longer exposures produced 100% right ventricular hypertrophy, with only moderate increases in hematocrit and left ventricular weight. It is well known that adrenergic stimulation causes cardiac hypertrophy, and it has been suggested that release of a trophic factor from sympathetic nerves, either noradrenaline or a protein, might be a necessary stimulus for growth. If so, long-term treatment of post-MI patients with beta-adrenergic blocking agents could inhibit a desirable compensatory hypertrophy of the surviving myocardium. In the above model it has been found, however, that neither beta-blockade nor chemical sympathectomy with guanethidine or 6-hydroxydopamine had any effect on the hypertrophy, nor did treatment with verapamil or nifedipine.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Genetic epidemiology of left ventricular hypertrophy

    PubMed Central

    Bella, Jonathan N; Göring, Harald HH

    2012-01-01

    Left ventricular (LV) hypertrophy is a strong independent predictor of increased cardiovascular morbidity and mortality in clinical and population-based samples. Clinical and hemodynamic stimuli to LV hypertrophy induce not only an increase in cardiac mass and wall thickness but also a fundamental reconfiguration of the protein, cellular and molecular components of the myocardium. Several studies have indicated that LV mass is influenced by genetic factors. The substantial heritability (h2) for LV mass in population-based samples of varying ethnicity indicates robust genetic influences on LV hypertrophy. Genome-wide linkage and association studies in diverse populations have been performed to identify genes influencing LV mass, and although several chromosomal regions have been found to be significantly associated with LV mass, the specific genes and functional variants contained in these chromosomal regions have yet to be identified. In addition, multiple studies have tried to link single-nucleotide polymorphisms (SNPs) in regulatory and pathway genes with common forms of LV hypertrophy, but there is little evidence that these genetic variations are functional. Up to this point in time, the results obtained in genetic studies are of limited clinical value. Much of the heritability remains unexplained, the identity of the underlying gene pathways, genes, and functional variants remains unknown, and the promise of genetically-based risk prediction and personalized medicine remain unfulfilled. However, molecular biological technologies continue to improve rapidly, and the long-term potential of sophisticated genetic investigations using these modern genomic technologies, coupled with smart study designs, remains intact. Ultimately, genetic investigations offer much promise for future prevention, early intervention and treatment of this major public health issue. PMID:23173100

  11. A novel mutation (Arg169Gln) of the cardiac ryanodine receptor gene causing exercise-induced bidirectional ventricular tachycardia.

    PubMed

    Hsueh, Chia-Hsiang; Weng, Yi-Chun; Chen, Chao-Yu; Lin, Tin-Kwang; Lin, Yen-Hung; Lai, Ling-Ping; Lin, Jiunn-Lee

    2006-04-01

    An 18-year-old woman presented with exercise induced sudden collapse. Series of cardiac work up revealed no structural cardiac abnormalities. Bidirectional ventricular tachycardia occurred during a treadmill exercise test. Under the impression of catecholaminergic polymorphic ventricular tachycardia, we screened the cardiac ryanodine receptor gene for mutation. We identified a novel heterozygous mutation at the 169th amino acid (Arg169Gln). This amino acid is highly conserved among many species and this mutation was not present in 50 normal control subjects. This patient was treated with a beta-block with good response. PMID:16517285

  12. Nomogram for calculation of left ventricular volumes.

    PubMed Central

    Saksena, F B; Saksena, G B

    1977-01-01

    A nomogram has been devised for the rapid derivation of left ventricular volumes from single-plane angiograms obtained in the 30 degrees right anterior oblique projection. The left ventricular volumes are derived from the use of the area-length formula of Dodge. The computed left ventricular volumes may then be adjusted to correspond to the actual volumes by an appropriate conversion chart. PMID:911567

  13. Association of the Functional MICA-129 Polymorphism With the Severity of Chronic Chagas Heart Disease.

    PubMed

    Ayo, Christiane Maria; Oliveira, Amanda Priscila de; Camargo, Ana Vitória da Silveira; Mattos, Cinara Cássia Brandão de; Bestetti, Reinaldo Bulgarelli; Mattos, Luiz Carlos de

    2015-10-15

    MICA-129 polymorphism affects the binding affinity of MICA molecules with the NKG2D receptor and influences effector cell function. The genotype met/met was associated with the severity of left ventricular systolic dysfunction (LVSD) in patients with chronic Chagas heart disease, while the val/val genotype was associated with the absence of LVSD.

  14. 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. PMID:26604120

  15. 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

  16. 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...

  17. 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...

  18. 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...

  19. Ventricular candidiasis in stone curlews (Burhinus oedicnemus).

    PubMed

    Caliendo, Valentina; Bull, Andrew

    2011-09-01

    Ventricular candidiasis is consistently one of the most prominent pathologic conditions diagnosed in stone curlews (Burhinus oedicnemus) in the United Arab Emirates, predominately affecting the captive population. Predisposing factors are a humid environment, stress, immunosuppression, inadequate nutrition, and an extended use of oral antibiotics. In this report, we describe the clinical signs, diagnosis, and pathologic result in stone curlews with ventricular candidiasis.

  20. Ventricular fibrillation coinciding with phentermine initiation.

    PubMed

    Tobbia, Patrick; Norris, Leslie A; Klima, Lawrence D

    2012-01-01

    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. PMID:23076689

  1. 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…

  2. What Is a Ventricular Assist Device?

    MedlinePlus

    ... basic types of VADs are a left ventricular assist device (LVAD) and a right ventricular assist device (RVAD). If both types are used at the same time, they're called a biventricular assist device (BIVAD). The LVAD is the most common type of VAD. It ...

  3. 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...

  4. 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...

  5. Circulatory support for right ventricular dysfunction.

    PubMed

    Jett, G K; Picone, A L; Clark, R E

    1987-07-01

    New modes of circulatory support for right ventricular dysfunction have recently been described. The present study compared the effectiveness of pulmonary artery balloon counterpulsation with a right ventricular assist device for support of surgically induced right ventricular dysfunction. Right ventricular hypertrophy was created in 16 neonatal lambs by pulmonary artery banding. Right ventricular dysfunction was produced in all animals by performing a right ventriculotomy and maintaining the pulmonary artery band. Four unassisted animals developed severe acute right heart failure and died. Six sheep had pulmonary artery balloon counterpulsation with a Dacron graft anastomosed to the proximal pulmonary artery as a reservoir for a 40 ml intra-aortic balloon after the onset of heart failure. The remaining six sheep had a pneumatically activated ventricular assist device inserted between the proximal pulmonary artery and the right ventricular apex. Periods of circulatory support with the balloon pump and the assist device on and off were compared. Decreases in right atrial pressure were observed with both balloon counterpulsation and right ventricular assistance: 14 +/- 1 to 11 +/- 1 mm Hg, p less than 0.0001, versus 19 +/- 2 to 12 +/- 2 mm Hg, p less than 0.0002, respectively. Cardiac output increased with both balloon counterpulsation and ventricular assistance: 1.45 +/- 0.16 to 2.03 +/- 0.13 L/min, p less than 0.001, versus 0.72 +/- 0.15 to 2.24 +/- 0.23 L/min, p less than 0.0002, respectively. Aortic systolic pressure increased in both support groups: 78 +/- 7 to 99 +/- 6 mm Hg, p less than 0.0004, versus 53 +/- 9 to 85 +/- 9 mm Hg, p less than 0.0001, respectively. Ventricular assistance produced greater changes in the right atrial pressure (39% +/- 6% versus 17% +/- 3%, p less than 0.01), cardiac output (153% +/- 39% versus 54% +/- 11%, p less than 0.05), and aortic systolic pressure (85% +/- 13% versus 39% +/- 9%, p less than 0.01). The insertion of a right

  6. 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.

  7. 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. PMID:15789811

  8. 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

  9. 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. PMID:26225205

  10. A Review of the Potential Pathogenicity and Management of Frequent Premature Ventricular Contractions.

    PubMed

    Laplante, Laurence; Benzaquen, Bruno S

    2016-07-01

    Very frequent premature ventricular complexes (PVCs) may be a reversible cause of dilated cardiomyopathy. Literature on this largely unrecognized entity has increased in the last 15 years. This paper reviews the literature on the consequences of frequent PVCs on myocardial function and management of PVC-associated cardiomyopathy. The authors reviewed articles published in English before June 2015 describing pathophysiology, risk factors, symptoms, time course, treatment, and outcome of cardiomyopathy associated with PVCs. The search was conducted using Medline and Embase. Keywords included: cardiomyopathy, catheter ablation, antiarrhythmic drug (AAD), pathophysiology, and ventricular premature contractions or synonyms. PVC-associated cardiomyopathy is associated with a high burden of PVC (over 20% of heartbeats). Other risk factors include electrophysiological characteristics, such as PVC QRS width, presence of ventricular tachycardia, retrograde P waves, interpolation, polymorphic PVCs, and longer coupling intervals. Symptoms include palpitations, light-headedness, dyspnea, cough, and dysphagia. The systolic dysfunction and chamber dilatation progress over a few years. Once the PVCs are suppressed by radiofrequency ablation or AADs, the cardiomyopathy usually resolves within 6 months. The pathophysiology remains unknown, but hypotheses mainly include ventricular dyssynchrony resulting in hemodynamic disturbances and abnormalities in calcium handling and oxygen consumption. PVC-associated cardiomyopathy remains a largely unrecognized entity. It is a reversible cause of dilated cardiomyopathy that results from abnormal calcium and oxygen handling within the myocyte, dyssynchrony, and hemodynamic compromise from inefficient heartbeats. Suppression of the PVCs improves myocardial function, cardiac chamber sizes, and patient's symptoms. PMID:27073007

  11. Coronary haemodynamics in left ventricular hypertrophy.

    PubMed Central

    Wallbridge, D. R.; Cobbe, S. M.

    1996-01-01

    BACKGROUND: Left ventricular hypertrophy is associated with an increased risk of cardiovascular morbidity and mortality. Previous studies have shown that patients with left ventricular hypertrophy develop electrocardiographic changes and left ventricular dysfunction during acute hypotension, and suggest that the lower end of autoregulation may be shifted upwards. AIM: To measure coronary blood flow (velocity) and flow reserve during acute hypotension in patients with left ventricular hypertrophy. PATIENTS: Eight patients with atypical chest pain and seven with hypertensive left ventricular hypertrophy; all with angiographically normal epicardial vessels. SETTING: Tertiary referral centre. METHODS: The physiological range of blood pressure was determined by previous ambulatory monitoring. Left ventricular mass was determined by echocardiography. At cardiac catheterisation, left coronary blood flow velocity was measured using a Judkins style Doppler tipped catheter. During acute hypotension with sodium nitroprusside, coronary blood flow velocity was recorded at rest and during maximal hyperaemia induced by intracoronary injection of adenosine. Quantitative coronary angiography was performed manually. RESULTS: For both groups coronary blood flow velocity remained relatively constant over a range of physiological diastolic blood pressures and showed a steep relation with diastolic blood pressure during maximal hyperaemia with intracoronary adenosine. Absolute coronary blood flow (calculated from quantitative angiographic data), standardised for left ventricular mass, showed reduced flow in the hypertensive group at rest and during maximal vasodilatation. CONCLUSION: The results are consistent with an inadequate blood supply to the hypertrophied heart, but no upward shift of the lower end of the autoregulatory range was observed. PMID:8705764

  12. Conquering the third ventricular chamber.

    PubMed

    Cohen-Gadol, Aaron A; Geryk, Bruce; Binder, Devin K; Tubbs, R Shane

    2009-09-01

    Surgery within the third ventricle was a special challenge early in the conception of the discipline of neurosurgery due to a lack of diagnostic methods and difficulty in reaching and removing lesions affecting this vital region. Walter Dandy and Harvey Cushing performed pioneering approaches of the third ventricular region. The authors have reviewed the previously undisclosed efforts of Cushing to approach the third ventricle through a direct review of his available patient records at the Cushing Brain Tumor Registry. The authors compare these efforts to those of Dandy published in Dandy's pioneering work Benign Tumors in the Third Ventricle of the Brain: Diagnosis and Treatment. Based on the review of these records, the authors attempt to examine the foundations of surgery within the third ventricle. PMID:19361257

  13. 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

  14. Renin-Angiotensin-Aldosterone Genotype Influences Ventricular Remodeling in Infants with Single Ventricle

    PubMed Central

    Mital, Seema; Chung, Wendy K.; Colan, Steven D.; Sleeper, Lynn A.; Manlhiot, Cedric; Arrington, Cammon B.; Cnota, James F.; Graham, Eric M.; Mitchell, Michael E.; Goldmuntz, Elizabeth; Li, Jennifer S.; Levine, Jami C.; Lee, Teresa M.; Margossian, Renee; Hsu, Daphne T.

    2011-01-01

    Background We investigated the effect of polymorphisms in the renin-angiotensin-aldosterone system (RAAS) genes on ventricular remodeling, growth, renal function and response to enalapril in infants with single ventricle. Methods and Results Single ventricle infants enrolled in a randomized trial of enalapril were genotyped for polymorphisms in 5 genes: angiotensinogen, angiotensin-converting enzyme, angiotensin II type 1 receptor, aldosterone synthase, and chymase. Alleles associated with RAAS upregulation were classified as risk alleles. Ventricular mass, volume, somatic growth, renal function using estimated glomerular filtration rate (eGFR), and response to enalapril were compared between patients with ≥2 homozygous risk genotypes (high-risk), and those with <2 homozygous risk genotypes (low-risk) at two time points - before the superior-cavopulmonary-connection (pre-SCPC) and at age 14 months. Of 230 trial subjects, 154 were genotyped: 38 were high-risk, 116 were low-risk. Ventricular mass and volume were elevated in both groups pre-SCPC. Ventricular mass and volume decreased and eGFR increased after SCPC in the low-risk (p<0.05) but not the high-risk group. These responses were independent of enalapril treatment. Weight and height z-scores were lower at baseline and height remained lower in the high-risk group at 14 months especially in those receiving enalapril (p<0.05). Conclusions RAAS-upregulation genotypes were associated with failure of reverse remodeling after SCPC surgery, less improvement in renal function, and impaired somatic growth, the latter especially in patients receiving enalapril. RAAS genotype may identify a high-risk subgroup of single ventricle patients who fail to fully benefit from volume unloading surgery. Follow-up is warranted to assess longterm impact. Clinical Trial Registration Clinical Trials.gov Identifier NCT00113087 PMID:21576655

  15. Management of Ventricular Arrhythmias in Patients with Mechanical Ventricular Support Devices.

    PubMed

    Healy, Chris; Viles-Gonzalez, Juan F; Sacher, Frederic; Coffey, James O; d'Avila, Andre

    2015-08-01

    The use of mechanical ventricular support devices in the management of patients with advanced heart failure continues to increase. These devices have been shown to prolong life as a destination therapy and to increase survival when used as a bridge to transplantation. However, they are associated with a high rate of complications, including bleeding, infection, device malfunction, and ventricular arrhythmias (VAs). The mechanical support provided by the device typically allows for VAs to be well tolerated in the acute setting, though there are numerous long-term complications related to VAs such as ventricular remodeling, right ventricular failure in patients with left ventricular assist devices, and possibly increased mortality. Controversy exists as to the appropriate role of implantable cardioverter defibrillators in these patients. This review will focus on the management options available for patients with mechanical ventricular support devices and VAs. PMID:26072439

  16. 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.

  17. 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.

  18. Sequential Notch activation regulates ventricular chamber development

    PubMed Central

    D'Amato, Gaetano; Luxán, Guillermo; del Monte-Nieto, Gonzalo; Martínez-Poveda, Beatriz; Torroja, Carlos; Walter, Wencke; Bochter, Matthew S.; Benedito, Rui; Cole, Susan; Martinez, Fernando; Hadjantonakis, Anna-Katerina; Uemura, Akiyoshi; Jiménez-Borreguero, Luis J.; de la Pompa, José Luis

    2016-01-01

    Ventricular chambers are essential for the rhythmic contraction and relaxation occurring in every heartbeat throughout life. Congenital abnormalities in ventricular chamber formation cause severe human heart defects. How the early trabecular meshwork of myocardial fibres forms and subsequently develops into mature chambers is poorly understood. We show that Notch signalling first connects chamber endocardium and myocardium to sustain trabeculation, and later coordinates ventricular patterning and compaction with coronary vessel development to generate the mature chamber, through a temporal sequence of ligand signalling determined by the glycosyltransferase manic fringe (MFng). Early endocardial expression of MFng promotes Dll4–Notch1 signalling, which induces trabeculation in the developing ventricle. Ventricular maturation and compaction require MFng and Dll4 downregulation in the endocardium, which allows myocardial Jag1 and Jag2 signalling to Notch1 in this tissue. Perturbation of this signalling equilibrium severely disrupts heart chamber formation. Our results open a new research avenue into the pathogenesis of cardiomyopathies. PMID:26641715

  19. Idiopathic left ventricular hypertrophy in an infant.

    PubMed

    Bhardwaj, Rajeev; Bhardwaj, Praveen

    2011-01-01

    Cardiac hypertrophy in infancy has been a subject of considerable interest. We present a case of significant left ventricular hypertrophy without any associated cause, presenting in infancy. PMID:23550435

  20. 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

  1. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) 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

    ...) 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, 2014 CFR

    2014-04-01

    ...) 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, 2011 CFR

    2011-04-01

    ...) 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. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) 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...

  6. Cardiac sarcoidosis mimicking right ventricular dysplasia.

    PubMed

    Shiraishi, Jun; Tatsumi, Tetsuya; Shimoo, Kazutoshi; Katsume, Asako; Mani, Hiroki; Kobara, Miyuki; Shirayama, Takeshi; Azuma, Akihiro; Nakagawa, Masao

    2003-02-01

    A 59-year-old woman with skin sarcoidosis was admitted to hospital for assessment of complete atrioventricular block. Cross-sectional echocardiography showed that the apical free wall of the right ventricle was thin and dyskinetic with dilation of the right ventricle. Thallium-201 myocardial imaging revealed a normal distribution. Both gallium-67 and technetium-99m pyrophosphate scintigraphy revealed no abnormal uptake in the myocardium. Right ventriculography showed chamber dilation and dyskinesis of the apical free wall, whereas left ventriculography showed normokinesis, mimicking right ventricular dysplasia. Cardiac sarcoidosis was diagnosed on examination of an endomyocardial biopsy specimen from the right ventricle. A permanent pacemaker was implanted to manage the complete atrioventricular block. After steroid treatment, electrocardiography showed first-degree atrioventricular block and echocardiography revealed an improvement in the right ventricular chamber dilation. Reports of cardiac sarcoidosis mimicking right ventricular dysplasia are extremely rare and as this case shows, right ventricular involvement may be one of its manifestations.

  7. Premature Ventricular Complexes and Premature Ventricular Complex Induced Cardiomyopathy.

    PubMed

    Latchamsetty, Rakesh; Bogun, Frank

    2015-09-01

    Presentation, prognosis, and management of premature ventricular complexes (PVCs) vary significantly among patients and depend on PVC characteristics as well as patient comorbidities. Presentation can range from incidental discovery in an asymptomatic patient to debilitating heart failure. Prognosis depends on, among other factors, the presence or absence of structural heart disease, PVC burden and other factors detailed in this review. Our understanding of the clinical significance of frequent PVCs, particularly as it relates to development of cardiomyopathy, has advanced greatly in the past decade. In this article, we explore the mechanisms governing PVC initiation and discuss prevalence and frequency of PVCs in the general population. We also explore prognostic implications based on PVC frequency as well as the presence or absence of underlying heart disease. We then take a focused look at PVC-induced cardiomyopathy and identify predictors for developing cardiomyopathy. Finally, we discuss clinical evaluation and management of patients presenting with frequent PVCs. Management can include clinical observation, addressing reversible causes, lifestyle modification, pharmacotherapy, or catheter ablation.

  8. Ventricular restoration--a surgical approach to reverse ventricular remodeling.

    PubMed

    Buckberg, Gerald D

    2004-10-01

    Congestive heart failure is most often caused by scar from coronary occlusion. The transition from occluded vessel to scar to dilation results in a remodeled ventricle that changes shape from ellipse to sphere. This shape change following an index event is called remodeling and a surgical approach for restoration (bring back to normal) will be described that uses the patient's own tissue, rather than employing heart replacement by mechanical devices or transplantation. The surgical restoration approach was taken by the RESTORE group that comprises an international medical and surgical team that will report (a) the remodeling infrastructure, role of compensatory remote muscle, and factors underlying surgical restoration decisions, (b) structural basis for ventricular geometric changes and surgical background for restoration, (c) individual rebuilding experience in 1150 patients over 20 years from one center, (d) integrated 5 year results from the RESTORE team in 1198 patients, (e) electrical aspects of restoration in 382 patients with only one AICD used, (f) how restoration improves mechanical synchrony without electrical devices, (g) geometric reasons for secondary mitral insufficiency and impact of adding mitral repair during SVR procedures, and (h) importance of defining site specific scar in no ischemic disease to identify a similar trigger lesion in non ischemic cardiomyopathy. The importance of a team approach by the RESTORE group may set the benchmark for collaborative world wide groups, and thereby depart from traditional focal approaches by individual disciplines. PMID:15886970

  9. Role of signal-averaged electrocardiography and ventricular late potentials in patients with chronic obstructive pulmonary disease.

    PubMed

    Buzea, C A; Dan, G A; Dan, Anca Rodica; Delcea, Caterina; Balea, M I; Gologanu, Daniela Stefana; Dobranici, Mihaela; Popescu, Raluca Alexandra

    2015-01-01

    Patients with chronic obstructive pulmonary disease (COPD) have an increased risk for cardiac arrhythmias. Ventricular late potentials (VLP) on signal-averaged electrocardiography (SAECG) are associated with an increased risk for malignant ventricular arrhythmias. Our aim is to investigate the modifications of SAECG parameters and the presence of VLP as possible indicators of proarrhythmic substrate in patients with COPD. We prospectively enrolled 41 consecutive patients in the COPD group and 63 patients without any history of pulmonary disease, matched for age and hypertension history, in the control group. Pulmonary function tests, arterial blood gases, echocardiography, 24-hour Holter monitoring and SAECG were performed. We measured total filtered QRS duration (QRSf), duration of high frequency, low-amplitude signals < 40 V (HFLA40), and root mean square voltage in the last 40 ms (RMS40). VLP were considered if at least two of these parameters were abnormal. Results. We did not register any significant differences in QRSf, HFLA40 or RMS40 between the two groups. In the COPD group there was a non-significant higher percentage of patients with VLP in comparison with the control group. In the COPD patients we registered a significantly higher number of isolated premature ventricular beats and of combined complex ventricular arrhythmias, consisting of polymorphic PVC, couplets, triplets or nonsustained ventricular tachycardias. None of these arrhythmic parameters correlated with SAECG variables or with the presence of VLP. Conclusion. In COPD patients parameters measured on signal-averaged electrocardiography and ventricular late potentials analysis have little value in risk stratification for ventricular arrhythmias.

  10. Right ventricular false tendons, a cadaveric approach.

    PubMed

    Loukas, Marios; Wartmann, Christopher T; Tubbs, R Shane; Apaydin, Nihal; Louis, Robert G; Black, Brandie; Jordan, Robert

    2008-06-01

    Left ventricular false tendons (LFTs) have been extensively described and recognized by gross anatomic studies. However, there is very little information available regarding right ventricular false tendons (RFTs). The aim of our study, therefore, was to explore and delineate the morphology, topography and morphometry of the RFTs, and provide a comprehensive picture of their anatomy across a broad range of specimens. We identified 35/100 heart specimens containing right ventricular RFTs and classified them into five types. In Type I (21, 47.7%) the RFTs, was located between the ventricular septum and the anterior papillary muscle; in Type II (11, 22.9%) between ventricular septum and the posterior papillary muscle; in Type III (7, 14.5%) between the anterior leaflet of the tricuspid valve and the right ventricular free wall; in Type IV (5, 10.4%) between the posterior papillary muscle and the ventricular free wall; and lastly, in Type V (4, 8.3%) between the anterior papillary muscle and ventricular free wall. The mean length of the RFTs was 18 +/- 7 mm with a mean diameter of 1.4 +/- 05 mm. Histologic examination with Masson trichrome and PAS revealed that 20 (41.6%) of the 48 RFTs carried conduction tissue fibers. The presence of conduction tissue fibers within the RFTs was limited to Types I, III, and IV. In Types II and V the RFTs resembled fibrous structures in contrast with Type I, II and IV, which were composed more of muscular fibers, including conduction tissue fibers. RFTs containing conduction tissue fibers were identified, which may implicate them in the appearance of arrhythmias.

  11. 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

  12. Venturing into ventricular arrhythmia storm: a systematic review and meta-analysis.

    PubMed

    Nayyar, Sachin; Ganesan, Anand N; Brooks, Anthony G; Sullivan, Thomas; Roberts-Thomson, Kurt C; Sanders, Prashanthan

    2013-02-01

    Ablation has substantial evidence base in the management of ventricular arrhythmia (VA). It can be a 'lifesaving' procedure in the acute setting of VA storm. Current reports on ablation in VA storm are in the form of small series and have relative small representation in a large observational series. The purpose of this study was to systematically synthesize the available literature to appreciate the efficacy and safety of ablation in the setting of VA storm. The medical electronic databases through 31 January 2012 were searched. Ventricular arrhythmia storm was defined as recurrent (≥ 3 episodes or defibrillator therapies in 24 h) or incessant (continuous >12 h) VA. Studies reporting data on VA storm patients at the individual or study level were included. A total of 471 VA storm patients from 39 publications were collated for the analysis. All VAs were successfully ablated in 72% [95% confidence interval (CI) 71-89%] and 9% (95% CI: 3-10%) had a failed procedure. Procedure-related mortality occurred in three patients (0.6%). Only 6% patients had a recurrence of VA storm. The recurrence of VA was significantly higher after ablation for arrhythmic storm of monomorphic ventricular tachycardia (VT) relative to ventricular fibrillation or polymorphic VT with underlying cardiomyopathy (odds ratio 3.76; 95% CI: 1.65-8.57; P = 0.002). During the follow-up (61 ± 37 weeks), 17% of patients died (heart failure 62%, arrhythmias 23%, and non-cardiac 15%) with 55% deaths occurring within 12 weeks of intervention. The odds of death were four times higher after a failed procedure compared with those with a successful procedure (95% CI: 2.04-8.01, P < 0.001). Ventricular arrhythmia storm ablation has high-acute success rates, with a low rate of recurrent storms. Heart failure is the dominant cause of death in the long term. Failure of the acute procedure carries a high mortality.

  13. Polymorphous computing fabric

    DOEpatents

    Wolinski, Christophe Czeslaw; Gokhale, Maya B.; McCabe, Kevin Peter

    2011-01-18

    Fabric-based computing systems and methods are disclosed. A fabric-based computing system can include a polymorphous computing fabric that can be customized on a per application basis and a host processor in communication with said polymorphous computing fabric. The polymorphous computing fabric includes a cellular architecture that can be highly parameterized to enable a customized synthesis of fabric instances for a variety of enhanced application performances thereof. A global memory concept can also be included that provides the host processor random access to all variables and instructions associated with the polymorphous computing fabric.

  14. Right ventricular mass estimation by angioechocardiography.

    PubMed

    Arcilla, R A; Mathew, R; Sodt, P; Lester, L; Cahill, N; Thilenius, O G

    1976-01-01

    A combined angiocardiographic-echocardiographic method for estimating right ventricular wall mass is described. Biplane cineangiocardiograms are analyzed for ventricular volume in end-diastole, and wall thickness is determined from echocardiograms obtained with a high frequency transducer and strip chart recorder, The intracavitary and the external surface volumes of the ventricle are derived, and the difference multiplied by 1.050, the specific gravity of myocardium. Excellent correlation was observed between right ventricular wall mass and body surface area in normal children (r = 0.93). The mean right ventricular mass was 44.5 g/M2 as compared to 78.1 g/M2 for the left ventricle, corresponding mass/EDV values were 0.48 g/cm3 and 1.26 g/cm3, respectively. In isolated right ventricular pressure overload, the increase in right ventricular mass is chiefly due to the increase in wall thickness; in volume overload, it is due mostly to the increase in chamber volume,

  15. [Ventricular contractility: Physiology and clinical projection].

    PubMed

    Domenech, Raúl J; Parra, Víctor M

    2016-06-01

    The contractile state of the heart is the result of myocardial contractility, the intrinsic mechanism that regulates the force and the shortening of the ventricle and determines the ventricular ejection volume. However, the ejection volume is also modulated by ventricular preload (diastolic ventricular volume) and afterload (resistance to ejection). Accordingly, a decrease in contractility may be masked by changes in preload or afterload, maintaining a normal ejection volume and delaying the diagnosis of myocardial damage. Thus, it is necessary to develop a non-invasive method to measure contractility in the clinical practice. We review in this article the basic principles of cardiac contraction, the concept of contractility and its measurement with the ventricular pressure-volume loop, an experimental method that also measures most of the hemodynamic variables of the cardiac cycle including preload, afterload, ventricular work, ventricular lusitropy and arterial elastance. This method has been recently validated in cardiac patients and allows to evaluate the evolution of contractility in heart failure in a non invasive way. Although some modifications are still necessary, it will probably have an extensive use in practical cardiology in the near future. PMID:27598497

  16. Association of angiotensin converting enzyme and angiotensin II type 1 receptor genotypes with left ventricular function and mass in patients with angiographically normal coronary arteries.

    PubMed Central

    Hamon, M.; Amant, C.; Bauters, C.; Richard, F.; Helbecque, N.; McFadden, E.; Lablanche, J. M.; Bertrand, M.; Amouyel, P.

    1997-01-01

    OBJECTIVE: To analyse the potential association of the angiotensin converting enzyme (ACE) and angiotensin II type 1 receptor (AT1R) gene polymorphisms on left ventricular function and mass in patients with normal coronary arteries. DESIGN: Consecutive sample. SETTING: University hospital. SUBJECTS: 141 consecutive white patients referred for coronary angiography and with angiographically normal coronary arteries. Patients with valvar diseases, cardiomyopathies, or a history of myocardial infarction were excluded. MAIN OUTCOME MEASURES: Left ventricular variables were measured for all patients. The ACE and AT1R genotypes were determined with a polymerase chain reaction based protocol using DNA prepared from white blood cells. A general linear model was used to compare data according to the ACE and to the AT1R genotypes. RESULTS: A strong association was observed between left ventricular mass and systemic hypertension (mean (SD) hypertension: 114 (31) g/m2; no hypertension 98 (23) g/m2; P < 0.003). However, no influence of ACE and AT1R polymorphisms on left ventricular mass was found, regardless of systemic hypertension. The subjects homozygous for the AT1R CC mutation had a significantly lower ejection fraction than those with allele A (AC+AA) (mean (SD) 62(12)% and 68(10)%, respectively, P < 0.05). No synergistic interaction of ACE and AT1R gene polymorphisms on left ventricular function and mass was found. CONCLUSIONS: These data do not support an association of the ACE and AT1R genotypes on left ventricular hypertrophy in white patients with normal coronary arteries. PMID:9227291

  17. 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. PMID:1457871

  18. Angiotensin-converting enzyme genetic polymorphism: its impact on cardiac remodeling

    PubMed Central

    de Albuquerque, Felipe Neves; Brandão, Andréa Araujo; da Silva, Dayse Aparecida; Mourilhe-Rocha, Ricardo; Duque, Gustavo Salgado; Gondar, Alyne Freitas Pereira; Neves, Luiza Maceira de Almeida; Bittencourt, Marcelo Imbroinise; Pozzan, Roberto; de Albuquerque, Denilson Campos

    2014-01-01

    Background The role of angiotensin-converting enzyme genetic polymorphisms as a predictor of echocardiographic outcomes on heart failure is yet to be established. The local profile should be identified so that the impact of those genotypes on the Brazilian population could be identified. This is the first study on exclusively non-ischemic heart failure over a follow-up longer than 5 years. Objective To determine the distribution of angiotensin-converting enzyme genetic polymorphism variants and their relation with echocardiographic outcome of patients with non-ischemic heart failure. Methods Secondary analysis of the medical records of 111 patients and identification of the angiotensin-converting enzyme genetic polymorphism variants, classified as DD (Deletion/Deletion), DI (Deletion/Insertion) or II (Insertion/Insertion). Results The cohort means were as follows: follow-up, 64.9 months; age, 59.5 years; male sex, 60.4%; white skin color, 51.4%; use of beta-blockers, 98.2%; and use of angiotensin-converting-enzyme inhibitors or angiotensin receptor blocker, 89.2%. The angiotensin-converting enzyme genetic polymorphism distribution was as follows: DD, 51.4%; DI, 44.1%; and II, 4.5%. No difference regarding the clinical characteristics or treatment was observed between the groups. The final left ventricular systolic diameter was the only isolated echocardiographic variable that significantly differed between the angiotensin-converting enzyme genetic polymorphisms: 59.2 ± 1.8 for DD versus 52.3 ± 1.9 for DI versus 59.2 ± 5.2 for II (p = 0.029). Considering the evolutionary behavior, all echocardiographic variables (difference between the left ventricular ejection fraction at the last and first consultation; difference between the left ventricular systolic diameter at the last and first consultation; and difference between the left ventricular diastolic diameter at the last and first consultation) differed between the genotypes (p = 0.024; p = 0.002; and p = 0

  19. Right ventricular volume analysis by angiography in right ventricular cardiomyopathy.

    PubMed

    Indik, Julia H; Dallas, William J; Gear, Kathleen; Tandri, Harikrishna; Bluemke, David A; Moukabary, Talal; Marcus, Frank I

    2012-06-01

    Imaging of the right ventricle (RV) for the diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is commonly performed by echocardiography or magnetic resonance imaging (MRI). Angiography is an alternative modality, particularly when MRI cannot be performed. We hypothesized that RV volume and ejection fraction computed by angiography would correlate with these quantities as computed by MRI. RV volumes and ejection fraction were computed for subjects enrolled in the North American ARVC/D Registry, with both RV angiography and MRI studies. Angiography was performed in the 30° right anterior oblique (RAO) and 60° left anterior oblique (LAO) views. Angiographic volumes were computed by RAO view and two-view (RAO and LAO) formulae. 17 subjects were analyzed (11 men and 6 women), with 15 subjects classified as affected, and two as unaffected by modified Task Force criteria. The correlation coefficient of MRI to the two-view angiographic analysis was 0.72 (P = 0.003) for end-diastolic volume and 0.68 (P = 0.005) for ejection fraction. Angiographically derived volumes were larger than MRI derived volume (P = 0.009) and with the slope in a linear relationship equal to 0.8 for end diastolic volume, and 0.9 for RV ejection fraction (P < 0.001), computed by the two view formula. End-diastolic volumes and ejection fractions of the RV obtained by dual view angiography correlate with these quantities by MRI. RV end-diastolic volumes are larger by RV angiography in comparison with MRI.

  20. Left ventricular function: time-varying elastance and left ventricular aortic coupling.

    PubMed

    Walley, Keith R

    2016-01-01

    Many aspects of left ventricular function are explained by considering ventricular pressure-volume characteristics. Contractility is best measured by the slope, Emax, of the end-systolic pressure-volume relationship. Ventricular systole is usefully characterized by a time-varying elastance (ΔP/ΔV). An extended area, the pressure-volume area, subtended by the ventricular pressure-volume loop (useful mechanical work) and the ESPVR (energy expended without mechanical work), is linearly related to myocardial oxygen consumption per beat. For energetically efficient systolic ejection ventricular elastance should be, and is, matched to aortic elastance. Without matching, the fraction of energy expended without mechanical work increases and energy is lost during ejection across the aortic valve. Ventricular function curves, derived from ventricular pressure-volume characteristics, interact with venous return curves to regulate cardiac output. Thus, consideration of ventricular pressure-volume relationships highlight features that allow the heart to efficiently respond to any demand for cardiac output and oxygen delivery. PMID:27613430

  1. Left ventricular oxygen consumption and organ blood flow distribution during pulsatile ventricular assist.

    PubMed

    Pantalos, G M; Marks, J D; Riebman, J B; Everett, S D; Burns, G L; Burton, N A; DePaulis, R

    1988-01-01

    One goal of left ventricular assistance is the reduction of left ventricular myocardial oxygen consumption while delivering adequate organ blood flow. The effect of assist device operation control mode and uptake cannulation method on the achievement of this goal was studied in six acutely prepared calves with healthy hearts. All combinations of left ventricular assistance significantly reduced the myocardial oxygen consumption; the reduction was independent of control mode. During ventricular assistance, regional organ blood flow distribution and myocardial endocardial/epicardial blood flow ratio were not different from values during the control, unassisted condition. Regardless of the left ventricular assist device uptake method or operational control mode, significant reduction in myocardial oxygen consumption was achieved while maintaining organ blood flow distribution.

  2. 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. PMID:23346986

  3. Catheter ablation of recurrent polymorphic tachycardia: Use of sodium channel blockade to organize the tachycardia: A case report

    PubMed Central

    Saggu, Daljeet Kaur; Nair, Sandeep G.; Shelke, Abhijeet; Yalagudri, Sachin; Narasimhan, Calambur

    2015-01-01

    A 55 year old male presented with recurrent implantable cardioverter defibrillator (ICD) shocks due to polymorphic ventricular tachycardia (PMVT). He had undergone prior catheter ablation for VT three years ago. During the prior attempt he underwent voltage guided substrate ablation. With programmed ventricular extrastimulation (PVES), PMVT was repeatedly induced requiring DC shock. Intravenous procainamide was administered and PVES was repeated which induced sustained monomorphic ventricular tachycardia (MMVT). This VT had pseudo delta waves with maximum deflection index of 0.68, suggestive of epicardial origin. Activation mapping was performed epicardially. Presystolic potentials were recorded in mid anterolateral wall of left ventricular epicardial region. Radiofrequency (RF) ablation at this site terminated the VT. Post ablation there was no inducible tachycardia and patient is free of arrhythmias during 2 years of follow-up. PMID:27479202

  4. Polymorphisms of β1-Adrenoreceptor Gene and Cardiovascular Complications in Patients with Thyrotoxicosis

    PubMed Central

    Babenko, A. Y.; Grineva, E. N.; Savitskaja, D. A.; Kravchuk, E. N.; Solncev, V. N.; Kostareva, A. A.

    2014-01-01

    Human cardiac β1-AR perform a crucial role in mediating the cardiostimulating effects of norepinephrine. Gly389Arg and Ser49Gly polymorphisms of β1-adrenoreceptors (β1-AR) can influence the cardiovascular prognosis. However, the possible effect of Gly389Arg and Ser49Gly polymorphisms on heart function in thyrotoxicosis has not been studied. We investigated the possible link between Gly389Arg and Ser49Gly polymorphisms and echocardiography parameters in 165 normotensive patients with a thyrotoxicosis without any cardiovascular disorders. Echo-CG was performed according to standard protocol before and during the thyreostatic treatment. Our data demonstrate that both Gly389Arg and Ser49Gly polymorphisms have very moderate influence on the risk of left ventricular hypertrophy and atrial fibrillation with no statistically significant effects on cardiac function and the development of cardiovascular complications. PMID:24982877

  5. Subdiaphragmatic murine electrophysiological studies: sequential determination of ventricular refractoriness and arrhythmia induction.

    PubMed

    Gutstein, David E; Danik, Stephan B; Sereysky, Jedd B; Morley, Gregory E; Fishman, Glenn I

    2003-09-01

    Programmed electrical stimulation (PES) is a crucial aspect of the evaluation of the risk of arrhythmias in cardiac patients and provides a powerful tool for understanding the mechanisms of arrhythmia in experimental models. Whereas PES in the mouse is well characterized, the procedures allowing for follow-up studies in the same animal have not been developed. In this report, we describe a novel subdiaphragmatic approach that allows for repeat electrophysiological studies in the mouse. Under inhaled anesthesia, PES was performed in 36 wild-type mice via a stimulating electrode introduced through an epigastric incision and placed directly into the diaphragmatic surface of the heart. The procedure was repeated 7 days later. Ventricular effective refractory periods (VERP) did not change significantly between the initial and follow-up trials. Chronic treatment with amiodarone, however, was associated with a 70% prolongation in VERP from initial to follow-up studies (P < or = 0.001). In addition, PES of a genetically modified strain with sudden cardiac death, the connexin43 conditional knockout mouse consistently induced lethal polymorphic ventricular tachycardia. Thus sequential PES in mice is feasible with the use of a subdiaphragmatic approach, yields reproducible VERP values, and can be used to follow pharmacologically induced changes in VERP and identify mice at risk of lethal ventricular arrhythmias. PMID:12750061

  6. 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.

  7. Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia1

    PubMed Central

    Indik, Julia H; Marcus, Frank I

    2003-01-01

    Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is characterized by the patchy replacement of myocardium by fatty or fibrofatty tissue. These changes lead to structural abnormalities including right ventricular enlargement and wall motion abnormalities that can be detected by echocardiography, angiography, and cine MRI. ARVC/D is a genetically heterogeneous disorder, since it has been linked to several chromosomal loci. Myocarditis may also be a contributing etiological factor. Patients are typically diagnosed during adolescence or young adulthood. Presenting symptoms are generally related to ventricular arrhythmias. Concern for the risk of sudden cardiac death may lead to the implantation of an intracardiac defibrillator. An ongoing multicenter international registry should further our understanding of this disease. PMID:16943913

  8. Left Ventricular Noncompaction: A Distinct Genetic Cardiomyopathy?

    PubMed

    Arbustini, Eloisa; Favalli, Valentina; Narula, Nupoor; Serio, Alessandra; Grasso, Maurizia

    2016-08-30

    Left ventricular noncompaction (LVNC) describes a ventricular wall anatomy characterized by prominent left ventricular (LV) trabeculae, a thin compacted layer, and deep intertrabecular recesses. Individual variability is extreme, and trabeculae represent a sort of individual "cardioprinting." By itself, the diagnosis of LVNC does not coincide with that of a "cardiomyopathy" because it can be observed in healthy subjects with normal LV size and function, and it can be acquired and is reversible. Rarely, LVNC is intrinsically part of a cardiomyopathy; the paradigmatic examples are infantile tafazzinopathies. When associated with LV dilation and dysfunction, hypertrophy, or congenital heart disease, the genetic cause may overlap. The prevalence of LVNC in healthy athletes, its possible reversibility, and increasing diagnosis in healthy subjects suggests cautious use of the term LVNC cardiomyopathy, which describes the morphology but not the functional profile of the cardiomyopathy. PMID:27561770

  9. Echocardiographic Evaluation of Left Ventricular Function, Mass and Wall Stress in Children with Isolated Ventricular Septal Defect

    PubMed Central

    Waggoner, Alan D.; Nouri, Soraya; Schaffer, Michael S.; Chen, Su-Chiung

    1985-01-01

    M-Mode echocardiography was performed in 22 normal children and 22 children with ventricular septal defects. Left ventricular and left atrial chamber dimensions and wall thicknesses were measured in all patients. Utilizing these data, indices of left ventricular function were derived: shortening fraction, velocity of fiber shortening, peak diastolic fiber lengthening, end-systolic wall stress, radius thickness ratio, and ventricular mass. The results showed that ventricular septal defect was associated with enlarged left ventricular and atrial dimensions and increased shortening fraction, but that velocity of shortening and early diastolic lengthening remained normal. Left ventricular mass was increased, thus maintaining normal wall stress and radius/thickness ratio. Cardiac failure complicating ventricular septal defect was associated with enlarged left ventricular and atrial dimensions (indexed for weight). Ventricular mass, wall stress and function, however, were similar in subjects with ventricular septal defect, with or without cardiac failure. Since left ventricular mass was adequate to maintain wall stress and function in subjects with heart failure, other factors were presumably responsible for heart failure complicating ventricular septal defect. PMID:15227026

  10. Ventricular tachycardia following trans-apical aortic valve replacement.

    PubMed

    Beinart, Roy; Danik, Stephan; Palacios, Igor; Barrett, Conor; Inglessis, Ignacio; Agnihotri, Arvind; Passeri, Jonathan

    2012-03-01

    Transcatheter aortic valve replacement (TAVR) is a relatively new procedure for high-risk patients with severe aortic stenosis. We report a case of a new left ventricular outflow tract ventricular tachycardia following TAVR. PMID:22016303

  11. [Right ventricular myxoma. A rare case of pulmonary stenosis].

    PubMed

    Riera, J M; Vila, I C; Serrano, J M; Aleixandre, L M; Baliarda, X R; de Auta, G M; Ruiz, F E; Domenech, J P; Garriga, J R

    1996-02-01

    We discuss a case of a fourteen year old girl in whom, clinical signs of right ventricular outflow obstruction were discovered following a syncopal attack. A right ventricular tumor was observed by echocardiography. Histology confirmed the diagnosis of myxoma.

  12. 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

  13. 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.

  14. 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

  15. Premature Ventricular Complexes in Apparently Normal Hearts.

    PubMed

    Luebbert, Jeffrey; Auberson, Denise; Marchlinski, Francis

    2016-09-01

    Premature ventricular complexes (PVCs) are consistently associated with worse prognosis and higher morbidity and mortality. This article reviews PVCs and their presentation in patients with an apparently normal heart. Patients with PVCs may be completely asymptomatic, whereas others may note severely disabling symptoms. Cardiomyopathy may occur with frequent PVCs. Diagnostic work-up is directed at obtaining 12-lead ECG to characterize QRS morphology, Holter monitor to assess frequency, and echo and advanced imaging to assess for early cardiomyopathy and exclude structural heart disease. Options for management include watchful waiting, medical therapy, or catheter ablation. Malignant variants of PVCs may induce ventricular fibrillation even in a normal heart. PMID:27521085

  16. 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.

  17. Arrhythmias in two patients with left ventricular bypass transplants.

    PubMed Central

    Kennelly, B M; Corte, P; Losman, J; Barnard, C N

    1976-01-01

    Two patients who underwent left ventricular bypass transplants are described. Both patients sustained postoperative rhythm disturbances of their own hearts during sinus rhythm of the donor hearts. Illustrative examples of atrial flutter, ventricular flutter, ventricular fibrillation, blocked atrial extrasystoles, and double ventricular parasystole in the recipient hearts are presented. The patients tolerated all these arrhythmias well during uninterrupted sinus rhythm in the donor heart. The problems in interpretation of arrhythmias in the presence of two hearts are discussed. Images PMID:788729

  18. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545 Ventricular bypass (assist) device. (a) Identification. A ventricular bypass (assist) device is a device that assists... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ventricular bypass (assist) device....

  19. 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

  20. [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. PMID:26928017

  1. Epicardial and endocardial mapping determine most successful site of ablation for ventricular tachyarrhythmias originating from left ventricular summit.

    PubMed

    Iijima, Kenichi; Chinushi, Masaomi; Furushima, Hiroshi; Aizawa, Yoshifusa

    2012-06-01

    A 34-year-old woman presented with idiopathic premature ventricular complex (PVC) and ventricular tachycardia (VT) originating from the area called the left ventricular summit. Radiofrequency (RF) application both through the coronary sinus and to the epicardial surface transiently suppressed the VT/PVC. Radiofrequency with sufficient energy was only applicable from the endocardial site, and the VT/PVC was successfully eliminated.

  2. 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.

  3. Mechanisms of ventricular arrhythmias: a perspective.

    PubMed

    Kléber, A G

    1991-01-01

    The most important ventricular arrhythmias, the ventricular tachycardias (VTs) and ventricular fibrillations (VFs), are thought to underlie the majority of cases of sudden cardiac death. In ischemic heart disease, they can be divided into several pathophysiological entities: (a) arrhythmias occurring during the acute reversible phase of ischemia, (b) arrhythmias taking place during reperfusion of acutely ischemic myocardium, (c) arrhythmias occurring 24-72 h after acute infarction, and (d) arrhythmias associated with chronic infarction. In all three settings, the mechanisms sustaining ventricular arrhythmias need to be distinguished from initiating mechanisms. With the exception of the 24-72-h stage, these arrhythmias are sustained by circus movement with reentry: the electrophysiological determinants of circus movements at a cellular level and, consequently, the appearance of the circulating wave fronts, differ according to the ischemic phase. In acute ischemia, multiple circulating waves, with somewhat large diameters, change their vortexes from beat to beat. In chronic infarction, the location of the stable circuits with elongated central zones of block are closely related to myocardial fiber architecture and probably to scar tissue. These differences indicate that (a) in acute ischemia, the conduction disturbances are mainly determined by the development of inexcitability at the level of cardiac membranes; and (b) in chronic infarction, the site of conduction block and the pivoting points of the wave fronts are determined by impairment of electrical cell-to-cell coupling. In contrast to the mechanisms sustaining VT and VF, the initiating mechanisms are less well defined.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1723111

  4. Catheter ablation of parahisian premature ventricular complex.

    PubMed

    Kim, Jun; Kim, Jeong Su; Park, Yong Hyun; Kim, June Hong; Chun, Kook Jin

    2011-12-01

    Catheter ablation is performed in selected patients with a symptomatic premature ventricular complex (PVC) or PVC-induced cardiomyopathy. Ablation of PVC from the His region has a high risk of inducing a complete atrioventricular block. Here we report successful catheter ablation of a parahisian PVC in a 63-year-old man.

  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. [Current management of patients with ventricular tachycardia].

    PubMed

    Puljević, D; Buljević, B; Milicić, D

    2001-01-01

    Ventricular arrhythmia has for decades been considered as a premonitory sign and risk marker of sudden death. Novel theories about arrhythmogenesis and conditions for the occurrence of sudden death, as well as evidence about proarrhythmic effect of antiarrhythmic drugs, have changed the views on the treatment of ventricular arrhythmia. Ventricular tachycardia (VT) is most often associated with structural heart disease: ischemic heart disease and previous myocardial infarction, cardiomyopathy (dilated and hypertrophic), arrhythmogenic right ventricular dysplasia, valvular heart disease (mitral valve prolapse), heart failure, condition after surgical correction of a congenital heart disease. Sometimes VT occurs without structural heart disease (congenital LQTS, Brugada syndrome, idiopathic VT). Today's standpoint is to treat only symptomatic and/or prognostically significant arrhythmias. Prognostic significance of VT mostly depends on the type and degree of structural heart disease and on global cardiac function. In patients with asymptomatic non-sustained VT and low risk for sudden death no treatment is needed or antiarrhythmics are administered. Conversely, in high risk patients implantation of automatic cardioverter-defibrillator is indicated. In the treatment of acute attack of VT the following can be used: electroconversion, cardiac pacing (overdrive), lidocaine, amiodarone, beta-blockers, and occasionally magnesium or verapamil. In the prevention of recurrent arrhythmia and sudden death we can use: amiodarone, sotalol, mexiletin, phenytoin, beta-blockers, radiofrequency ablation, implantable cardioverter-defibrillator, and in specific patients verapamil, pacemaker or left ganglion stellatum denervation.

  7. Diagnosis and management of ventricular dysphonia.

    PubMed

    Von Hake, C P; Ganzman, I P; Mauer, T P

    1989-02-01

    Ventricular phonation may develop on a functional level, or it may occur as an alternative voice for the patient who has an organic disease of the true vocal folds. Three cases that represent iatrogenic, traumatic, and neurologic forms of the disorder are reported. Diagnosis, treatment, and guidelines for follow-up speech therapy are discussed.

  8. Action of ATP on ventricular automaticity.

    PubMed

    Stark, G; Domanowits, H; Sterz, F; Stark, U; Bachernegg, M; Kickenweiz, E; Decrinis, M; Laggner, A N; Tritthart, H A

    1994-11-01

    ATP is an effective treatment of supraventricular tachycardia when the atrioventricular (AV) node is part of the reentrant circuit. However, the lower a pace-maker in the pacemaker hierarchy, the more sensitive it is to adenosine. Therefore, we investigated the effects of ATP on ventricular automaticity in in vivo and in vitro conditions. Wide and narrow QRS complex tachycardia in 46 patients was treated with 6, 12, and 18 mg ATP as sequential intravenous (i.v.) bolus. ATP terminated tachycardias in 67%. Bolus infusion ATP caused < or = 6.4-s asystole that was self-limited. Perfusion of isolated spontaneously beating guinea pig heart with 100 microM ATP completely suppressed ventricular automaticity. After ATP-infusion was discontinued, the first ventricular beat was evident after 3.1 +/- 0.9 s and sinus node activity recovered with a time constant of 3.0 +/- 1.1 s. Because sinus node and ventricular automaticity recovered within seconds after ATP infusion was discontinued in vitro, recovery in vivo is also likely to be determined by the short half-life (+1/2) of ATP. PMID:7532751

  9. Comparison of effectiveness of right ventricular septal pacing versus right ventricular apical pacing.

    PubMed

    Cano, Oscar; Osca, Joaquín; Sancho-Tello, María-José; Sánchez, Juan M; Ortiz, Víctor; Castro, José E; Salvador, Antonio; Olagüe, José

    2010-05-15

    Chronic right ventricular apical pacing (RVAP) has been associated with negative hemodynamic and clinical effects. The aim of the present study was to compare RVAP with right ventricular septal pacing (RVSP) in terms of echocardiographic features and clinical outcomes. A total of 93 patients without structural heart disease and with an indication for a permanent pacemaker were randomly assigned to receive a screw-in lead either in the RV apex (n = 46) or in the RV mid-septum (n = 47). The patients were divided into 3 subgroups according to the percentage of ventricular pacing: control group (n = 21, percentage of ventricular pacing < or =10%), RVAP group (n = 28), or RVSP group (n = 32; both latter groups had a percentage of ventricular pacing >10%). The RVAP group had more intraventricular dyssynchrony and a trend toward a worse left ventricular ejection fraction compared to the RVSP and control groups at 12 months of follow-up (maximal delay to peak systolic velocity between any of the 6 left ventricular basal segments was 57.8 +/- 38.2, 35.5 +/- 20.6, and 36.5 +/- 17.8 ms for RVAP, RVSP, and control group, respectively; p = 0.006; mean left ventricular ejection fraction 62.9 +/- 7.9%, 66.5 +/- 7.2%, and 66.6 +/- 7.2%, respectively, p = 0.14). Up to 48.1% of the RVAP patients showed significant intraventricular dyssynchrony compared to 19.4% of the RVSP patients and 23.8% of the controls (p = 0.04). However, no overt clinical benefits from RVSP were found. In conclusion, RVAP was associated with increased dyssynchrony compared to the RVSP and control patients. RVSP could represent an alternative pacing site in selected patients to reduce the harmful effects of traditional RVAP. PMID:20451689

  10. Catheter ablation of ventricular tachycardia related to a septo-apical left ventricular aneurysm

    PubMed Central

    Rosu, Radu; Cismaru, Gabriel; Muresan, Lucian; Puiu, Mihai; Andronache, Marius; Gusetu, Gabriel; Pop, Dana; Mircea, Petru-Adrian; Zdrenghea, Dumitru

    2015-01-01

    A 60-year-old male patient with previous myocardial infarction (30 years ago) presented to our cardiology department for sustained monomorphic ventricular tachycardia. The patient presented multiple episodes of tachycardia treated by his internal cardiac defibrillator. Radiofrequency ablation was proposed as curative treatment. The mechanism of the ventricular tachycardia was demonstrated by electrophysiological study using three-dimensional mapping system: Carto 3 (Biosense Webster). Ventricular tachycardia was induced either mechanically or by programmed ventricular stimulation. The tachycardia cycle length was 380 msec. The voltage map confirmed the presence of the septo-apical aneurysm with a local voltage < 0.5 mV. Activation mapping revealed a figure-in-8 circuit of VT with the entrance point inside the dense scar and the exit point at the border zone (between the aneurysm and the healthy tissue of the left ventricular septo-apical region). Radiofrequency energy was delivered at the isthmus of the tachycardia rendering it uniducible by programmed ventricular stimulation. PMID:26770613

  11. Fontan-Like Hemodynamics Complicated With Ventricular Fibrillation During Left Ventricular Assist Device Support.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro; Nitta, Daisuke; Kinoshita, Osamu; Nawata, Kan; Ono, Minoru

    2016-07-27

    We experienced a patient who had received an implantable continuous-flow left ventricular assist device (LVAD) (HeartMate II, Thoratec Corp, Pleasanton, CA, USA) and was admitted to our hospital because of repeated ventricular tachyarrhythmias refractory to electrical defibrillation as well as intensive pharmacological therapy. We decided to discontinue defibrillating, but under ventricular fibrillation his hemodynamics were maintained without end-organ dysfunction during LVAD support (mean right atrial pressure 18 mmHg; pulmonary vascular resistance 1.6 WU; pulmonary capillary wedge pressure 11 mmHg; cardiac index 2.04 L/minute/m(2)) due to optimization of the rotation speed (from 8800 to 9200 rpm). Such "Fontan-like circulation" could be accomplished by adequate volume control, lowering pulmonary vascular resistance, and potent LV blood removal by optimal rotation speed of the LVAD, although the precise conditions to maintain the Fontan-like circulation during LVAD therapy remained uncertain. Considering the severe donor heart shortage and high degree of difficulty of the catheter ablation procedure to manage ventricular tachyarrhythmias, constructing a Fontan-like circulation in the presence of ventricular tachyarrhythmias may be one unique strategy. Longterm prognosis in patients with sustained ventricular tachyarrhythmias during LVAD support would be a future concern. PMID:27385606

  12. Left ventricular function in chronic aortic regurgitation

    SciTech Connect

    Iskandrian, A.S.; Hakki, A.H.; Manno, B.; Amenta, A.; Kane, S.A.

    1983-06-01

    Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (greater than or equal to 7.0 minutes) had a significantly higher ejection fraction at rest (probability (p) . 0.02) and during exercise (p . 0.0002), higher cardiac index at exercise (p . 0.0008) and lower exercise end-systolic volume (p . 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both p . 0.001) and cardiac index at rest (p . 0.03) and exercise (p . 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean +/- standard deviation 476 +/- 146 versus 377 +/- 92 mm Hg, p less than 0.05). Thus, in patients with chronic aortic regurgitation: 1) left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and 2) the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest.

  13. 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.

  14. [Influence of polymorphism's of endothelial nitric oxide synthase gene and polymorphism of NADPH oxidase gene on development of complications of arterial hypertension].

    PubMed

    Kuznetsova, T Iu; Gavrilov, D V; Dudanov, I P; Makarevich, P I; Balatskiĭ, A V; Samokhodskaia, L M; Parfenova, E V

    2008-01-01

    The aim of the study was to analyze the prevalence of polymorphism Glu298Asp of endothelial nitric oxide synthase gene and C242T p22 phox polymorphism of NADPH oxidase gene in patients with arterial hypertension (AH) and their influence on AH complications. The study included 272 AH patients, average age 50,7 years. The following analyses were performed: clinical analysis of the blood, general analysis of the urine, lipid spectrum, plasma electrolytes, creatinine, glucose, electrocardiography, echocardioscopy, examination of eye vessels, ultrasound examination of the carotid arteries, determination of microalbuminuria. The polymorphism Glu298Asp of endothelial nitric oxide synthase gene and C242T p22 phox polymorphism of NADPH oxidase gene were detected with two methods: polymerase chain reaction and restrictase reaction. The control group for Glu298Asp polymorphism detection included 102 healthy Russian donors aged 18 to 50 years. Genotypes prevalence in AH patients was as follows: GG 58,8%, GA 32,3%, AA 8,9%, and CC 48,2%, CT 44,9%, TT 6.9%. In the control group: GG 53%, GA 36%, AA 11% and CC 42%, CT 54%, TT 4%. These polymorphisms did not affect the incidence of complications, such as obliterating atherosclerosis of the lower extremity vessels, ischemic heart disease, and acute insufficiency of cerebral circulation, chronic heart failure, left ventricular hypertrophy, microalbuminuria, carotid arteries atherosclerosis. PMID:18429753

  15. Right ventricular filling in dilated cardiomyopathy.

    PubMed Central

    Fujimoto, S.; Parker, K. H.; Gibson, D. G.

    1995-01-01

    PURPOSE--To assess right ventricular filling in dilated cardiomyopathy. PATIENTS--32 patients with dilated cardiomyopathy and 24 healthy controls. METHODS--Stroke distances were measured by pulsed Doppler echocardiography at left ventricular outflow and left and right ventricular inflow. The inflow tract dimensions of both ventricles and the outflow tract dimension of the left ventricle were measured from two dimensional images. Right and left sided atrioventricular (AV) ring excursions were measured by M mode echocardiography at the tricuspid and mitral rings. Stroke volume was derived as stroke distance multiplied by left ventricular outflow tract area. Total stroke distances were calculated as the sum of AV valve Doppler stroke distances and ring excursion. The effective orifice areas of the two AV valves were thus defined as stroke volumes divided by total stroke distance. RESULTS--Total tricuspid stroke distance was normally less than mitral (6.0 (1.7) v 7.6 (1.7) cm, P < 0.05), implying that effective orifice area of the tricuspid valve was consistently greater (6.6 (1.6) v 4.5 (0.8) cm2, P < 0.01). Total tricuspid ring excursion was normally more than mitral (2.30 (0.30) v 1.62 (0.22) cm, P < 0.01). Total tricuspid stroke distance in dilated cardiomyopathy was also less than mitral (7.8 (2.4) v 9.7 (2.8) cm, P < 0.05). Tricuspid stroke distance was significantly increased in patients with dilated cardiomyopathy compared with that in healthy controls (P < 0.05 v controls), though stroke volume was much smaller (26 (10) v 63 (11) ml, P < 0.01) so that tricuspid effective orifice area was reduced to less than half normal (2.7 (1.2) cm2, P < 0.01). Total tricuspid ring long axis excursion was more than mitral (1.37 (0.6) v 0.74 (0.21) cm, P < 0.01). Right ventricular end diastolic inflow dimension was increased compared with that in healthy controls (3.9 (0.7) v 2.8 (0.5) cm, P < 0.01), correlating inversely with tricuspid effective orifice area (r = -0.71, P

  16. Disappearing Polymorphs Revisited

    PubMed Central

    Bučar, Dejan-Krešimir; Lancaster, Robert W; Bernstein, Joel

    2015-01-01

    Nearly twenty years ago, Dunitz and Bernstein described a selection of intriguing cases of polymorphs that disappear. The inability to obtain a crystal form that has previously been prepared is indeed a frustrating and potentially serious problem for solid-state scientists. This Review discusses recent occurrences and examples of disappearing polymorphs (as well as the emergence of elusive crystal forms) to demonstrate the enduring relevance of this troublesome, but always captivating, phenomenon in solid-state research. A number of these instances have been central issues in patent litigations. This Review, therefore, also highlights the complex relationship between crystal chemistry and the law. PMID:26031248

  17. Electrocardiographic and morphometric features in patients with ventricular tachycardia of right ventricular origin

    PubMed Central

    Kazmierczak, J; De Sutter, J; Tavernier, R; Cuvelier, C; Dimmer, C; Jordaens, L

    1998-01-01

    Objective—To study differences between repetitive monomorphic ventricular tachycardia (RMVT) of right ventricular origin, and ventricular tachycardia in arrhythmogenic right ventricular dysplasia (ARVD).
Patients—Consecutive groups with RMVT (n = 15) or ARVD (n = 12), comparable for age and function.
Methods—Analysis of baseline, tachycardia, and signal averaged ECGs, clinical data, and right endomyocardial biopsies. Pathological findings were related to regional depolarisation (QRS width) and repolarisation (QT interval, QT dispersion).
Results—There was no difference in age, ejection fraction, QRS width in leads I, V1, and V6, and QT indices. During ventricular tachycardia, more patients with ARVD had a QS wave in V1 (p < 0.05). There were significant differences for unfiltered QRS, filtered QRS, low amplitude signal duration, and the root mean square voltage content. In the absence of bundle branch block, differences became non-significant for unfiltered and filtered QRS duration. Mean (SD) percentage of biopsy surface differed between RMVT and ARVD: normal myocytes (74(3.4)% v 64.5(9.3)%; p < 0.05); fibrosis (3(1.7)% v 8.9(5.2)%; p < 0.05). When all patients were included, there were significant correlations between fibrosis and age (r = 0.6761), and fibrosis and QRS width (r = 0.5524 for lead I; r = 0.5254 for lead V1; and r = 0.6017 for lead V6).
Conclusions—The ECG during tachycardia and signal averaging are helpful in discriminating between ARVD and RMVT patients. There are differences in the proportions of normal myocytes and fibrosis. The QRS duration is correlated with the amount of fibrous tissue in patients with ventricular tachycardia of right ventricular origin.

 Keywords: arrhythmogenic right ventricular dysplasia;  electrocardiography;  endomyocardial biopsy;  ventricular arrhythmias PMID:9616349

  18. Left Ventricular Dilatation Increases the Risk of Ventricular Arrhythmias in Patients With Reduced Systolic Function

    PubMed Central

    Aleong, Ryan G; Mulvahill, Matthew J; Halder, Indrani; Carlson, Nichole E; Singh, Madhurmeet; Bloom, Heather L; Dudley, Samuel C; Ellinor, Patrick T; Shalaby, Alaa; Weiss, Raul; Gutmann, Rebecca; Sauer, William H; Narayanan, Kumar; Chugh, Sumeet S; Saba, Samir; London, Barry

    2015-01-01

    Background Reduced left ventricular (LV) ejection fraction increases the risk of ventricular arrhythmias; however, LV ejection fraction has a low sensitivity to predict ventricular arrhythmias. LV dilatation and mass may be useful to further risk-stratify for ventricular arrhythmias. Methods and Results Patients from the Genetic Risk of Assessment of Defibrillator Events (GRADE) study (N =930), a study of heart failure subjects with defibrillators, were assessed for appropriate implantable cardioverter-defibrillator shock and death, heart transplant, or ventricular assist device placement by LV diameter and mass. LV mass was divided into normal, mild, moderate, and severe classifications. Severe LV end-diastolic diameter had worse shock-free survival than normal and mild LV end-diastolic diameter (P =0.0002 and 0.0063, respectively; 2-year shock free, severe 74%, moderate 80%, mild 91%, normal 88%; 4-year shock free, severe 62%, moderate 69%, mild 72%, normal 81%) and freedom from death, transplant, or ventricular assist device compared with normal and moderate LV end-diastolic diameter (P<0.0001 and 0.0441, respectively; 2-year survival: severe 78%, moderate 85%, mild 82%, normal 89%; 4-year survival: severe 55%, moderate 64%, mild 63%, normal 74%). Severe LV mass had worse shock-free survival than normal and mild LV mass (P =0.0370 and 0.0280, respectively; 2-year shock free: severe 80%, moderate 81%, mild 91%, normal 87%; 4-year shock free: severe 68%, moderate 73%, mild 76%, normal 76%) but no association with death, transplant, or ventricular assist device (P =0.1319). In a multivariable Cox proportional hazards analysis adjusted for LV ejection fraction, LV end-diastolic diameter was associated with appropriate implantable cardioverter-defibrillator shocks (hazard ratio 1.22, P =0.020). LV end-diastolic diameter was associated with time to death, transplant, or ventricular assist device (hazard ratio 1.29, P =0.0009). Conclusions LV dilatation may complement

  19. Morphometric analysis of cerebral ventricular system from MR images

    NASA Astrophysics Data System (ADS)

    Aziz, Aamer; Hu, QingMao; Nowinski, Wieslaw L.

    2004-04-01

    Cerebrospinal fluid filled ventricular system is an essential part of brain. The volume, shape and size of this ventricular system remain more or less constant and various pathologies directly or indirectly affect them. Morphometric analysis of cerebral ventricular system is important for evaluating changes due to growth, aging, intrinsic and extrinsic pathologies. Previous quantification efforts using ex vivo techniques suffered considerable error due to deformation of slices during sectioning, and numerous other factors. In vivo studies using air or contrast media also introduce volumetric changes in the ventricles thus giving erroneous quantitative information. Imaging of ventricular anatomy avoids these problems and allows repetitive studies following progression of ventricular system changes due to disease or natural processes. We have developed a methodology for automated extraction of ventricular system from MR neuroimages. Once extracted, landmarks are located on the surface of ventricular system automatically. These landmarks are then used for calculation of the ventricular shape, volume and size. A total of 20 brain ventricular systems were analyzed. The morphometric dimensions of the ventricles are presented in this paper. This study forms an initial basis for more advanced work on ventricular segmentation and morphometry.

  20. Patient selection for left ventricular assist devices.

    PubMed

    Lund, Lars H; Matthews, Jennifer; Aaronson, Keith

    2010-05-01

    Heart transplantation (HTx) improves symptoms and prolongs life in advanced heart failure (HF), but organ supply is limited. In recent years, mechanical circulatory support and specifically implantable left ventricular assist devices (LVADs) have undergone technical improvements, and outcomes have improved dramatically. Left ventricular assist devices are now viable options for patients with severe HF as bridge to transplantation, destination therapy, or as bridge to recovery. Many believe that LVADs may soon provide outcomes similar to, or better than, HTx, launching a new era of end-stage HF management. The key to improving outcomes is patient selection, but the field is changing rapidly and guidelines and consensus are limited. This review summarizes recent reports of predictors of poor outcomes and provides an overview of selection for LVAD therapy. PMID:20172939

  1. Ventricular assist device in univentricular heart physiology.

    PubMed

    Brancaccio, Gianluca; Gandolfo, Fabrizio; Carotti, Adriano; Amodeo, Antonio

    2013-04-01

    The use of mechanical cardiac assistance is well established as a bridge to orthotopic heart transplantation (OHT) or to recovery for patients with congestive heart failure, however, the experience in single ventricle (SV) physiology is still limited. We report two cases of mechanical assistance in patients with SV physiology: a 2-year old male with hypoplastic left heart syndrome who underwent Norwood Stage I and II followed by HF and a 4-year old female with a univentricular heart who developed a severe right ventricular dysfunction 2 years after a cavopulmonary shunt. Mechanical support utilizing ventricular assist devices (VADs) is considered a valid tool to bridge patients with congestive heart failure to either OHT or to recovery. Increasing experience and improved outcomes utilizing this technology in children with biventricular hearts have led to considering employing these devices in failing SV treatment. We present 2 cases of terminally ill children with SV who were assisted with a VAD.

  2. Ventricular fibrillation during sport activity successfully treated.

    PubMed

    Gonzalez, Maria Margarita; Marques, Flávio Rocha Brito; Vianna, Caio Brito; Eid, Carlos Alberto; Feitosa-Filho, Gilson Soares; Timerman, Sergio

    2009-08-01

    Survival after out-of-hospital cardiopulmonary arrest is estimated at less than 5%. We report a case of ventricular fibrillation during sports activity. Cardiopulmonary resuscitation was initiated early by a layperson, and defibrillation was successfully performed within less than three minutes, with an automated external defibrillator. The public access to defibrillation programs has increased the survival after out-of-hospital ventricular fibrillation. We should encourage the training of laypeople in relation to the use of automated external defibrillators and the Basic Life Support program by stimulating their implementation in places where large numbers of people gather or where people are at a high risk of sudden death, as is the case of sports centers.

  3. Youngest case of third ventricular anaplastic neurocytoma.

    PubMed

    Shravan Kumar, Chinnikatti; Sharma, D N; Sharma, Kuldeep; Haresh, K P; Rath, G K

    2010-04-01

    A 6-year-old child presented to us with on and off headache and vomiting for 4 months. On examination, there was bilateral papilledema with mild intracranial hypertension but with no neurological deficits. Magnetic resonance imaging (MRI) showed third ventricular mass with obstructive hydrocephalus with possibility of glioma. The patient underwent gross tumor excision and histopathology confirmed anaplastic neurocytoma. The postoperative MRI showed residual disease. The patient treated with adjuvant radiotherapy and temozolamide chemotherapy. PMID:21209769

  4. Youngest case of third ventricular anaplastic neurocytoma

    PubMed Central

    Shravan Kumar, Chinnikatti; Sharma, D. N.; Sharma, Kuldeep; Haresh, K. P.; Rath, G. K.

    2010-01-01

    A 6-year-old child presented to us with on and off headache and vomiting for 4 months. On examination, there was bilateral papilledema with mild intracranial hypertension but with no neurological deficits. Magnetic resonance imaging (MRI) showed third ventricular mass with obstructive hydrocephalus with possibility of glioma. The patient underwent gross tumor excision and histopathology confirmed anaplastic neurocytoma. The postoperative MRI showed residual disease. The patient treated with adjuvant radiotherapy and temozolamide chemotherapy. PMID:21209769

  5. [Ventricular fibrillation following deodorant spray inhalation].

    PubMed

    Girard, F; Le Tacon, S; Maria, M; Pierrard, O; Monin, P

    2008-01-01

    We report one case of out-of-hospital cardiac arrest with ventricular fibrillation following butane poisoning after inhalation of antiperspiration aerosol. An early management using semi-automatic defibrillator explained the success of the resuscitation. The mechanism of butane toxicity could be an increased sensitivity of cardiac receptors to circulating catecholamines, responsible for cardiac arrest during exercise and for resuscitation difficulties. The indication of epinephrine is discussed.

  6. Left ventricular heart failure and pulmonary hypertension†

    PubMed Central

    Rosenkranz, Stephan; Gibbs, J. Simon R.; Wachter, Rolf; De Marco, Teresa; Vonk-Noordegraaf, Anton; Vachiéry, Jean-Luc

    2016-01-01

    In patients with left ventricular heart failure (HF), the development of pulmonary hypertension (PH) and right ventricular (RV) dysfunction are frequent and have important impact on disease progression, morbidity, and mortality, and therefore warrant clinical attention. Pulmonary hypertension related to left heart disease (LHD) by far represents the most common form of PH, accounting for 65–80% of cases. The proper distinction between pulmonary arterial hypertension and PH-LHD may be challenging, yet it has direct therapeutic consequences. Despite recent advances in the pathophysiological understanding and clinical assessment, and adjustments in the haemodynamic definitions and classification of PH-LHD, the haemodynamic interrelations in combined post- and pre-capillary PH are complex, definitions and prognostic significance of haemodynamic variables characterizing the degree of pre-capillary PH in LHD remain suboptimal, and there are currently no evidence-based recommendations for the management of PH-LHD. Here, we highlight the prevalence and significance of PH and RV dysfunction in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), and provide insights into the complex pathophysiology of cardiopulmonary interaction in LHD, which may lead to the evolution from a ‘left ventricular phenotype’ to a ‘right ventricular phenotype’ across the natural history of HF. Furthermore, we propose to better define the individual phenotype of PH by integrating the clinical context, non-invasive assessment, and invasive haemodynamic variables in a structured diagnostic work-up. Finally, we challenge current definitions and diagnostic short falls, and discuss gaps in evidence, therapeutic options and the necessity for future developments in this context. PMID:26508169

  7. Ventricular assist devices: The future is now.

    PubMed

    Lima, Brian; Mack, Michael; Gonzalez-Stawinski, Gonzalo V

    2015-05-01

    Heart failure has become a global epidemic. For advanced heart failure, a broad assortment of device options have been introduced for both acute and prolonged intervals of hemodynamic assistance. Durable implantable ventricular assist devices (VADs) in particular play a key role in the management of advanced heart failure. This review focuses specifically on the current outcomes with VAD therapy, highlights the results from pivotal clinical trials, and summarizes the various device options on the market and those in preclinical development. PMID:25596799

  8. Salbutamol Abuse is Associated with Ventricular Fibrillation.

    PubMed

    Uysal, Emin; Solak, Suleyman; Carus, Murat; Uzun, Nedim; Cevik, Erdem

    2015-06-01

    Salbutamol-induced cardiac complications are well-established. Herein, we describe a case of a 24-year female who was admitted to the emergency department because of a suicide attempt with salbutamol (76 mg). Salbutamol abuse induced the development of supraventricular tachycardia and ventricular fibrillation. Regular sinus rhythm was restored with defibrillation. The hypokalemic patient who stayed in the intensive care unit was discharged after 48 hours of hospitalization. PMID:27336070

  9. Dynamic aortomyoplasty to assist left ventricular failure.

    PubMed

    Chachques, J C; Grandjean, P A; Cabrera Fischer, E I; Latremouille, C; Jebara, V A; Bourgeois, I; Carpentier, A

    1990-02-01

    The efficacy of skeletal muscle contractile force to augment left ventricular function has been demonstrated experimentally and clinically by the cardiomyoplasty procedure. Another approach in biomechanical cardiac assistance is the use of electrostimulated skeletal muscle in an extracardiac position. We describe an autologous counterpulsating device using the native ascending aorta as a ventricular chamber wrapped by an electrostimulated latissimus dorsi muscle flap (LDMF). This model avoids thrombotic complications observed in skeletal muscle neo-ventricles associated with prosthetic chambers. In 8 goats, a right LDMF was transferred to the thoracic cavity by removal of the second rib. In 4 goats, the diameter of the aorta was enlarged by surgical implantation (using lateral clamping) of an autologous pericardial patch. The LDMF was wrapped around the ascending aorta and electrostimulated using an external diastolic pulse generator connected to a sensing myocardial lead and to LDMF pacing electrodes. Hemodynamic studies were performed (left ventricular, aortic, and pulmonary artery pressures and rate of rise of left ventricular pressure). The LDMF diastolic counterpulsation was performed using a burst of 30 Hz, with a delay from the R wave adjusted to provide optimal diastolic augmentation. Percent increase in the subendocardial viability index was calculated during unassisted and assisted cardiac cycles (1:2) at baseline and after acute heart failure induced by the administration of high doses of propranolol hydrochloride (3 mg/kg intravenously). Diastolic aortic counterpulsation by the stimulated LDMF resulted in a significant improvement in the subendocardial viability index both at baseline and after induced cardiac failure in both groups, though the increase was greater in the group with aortic enlargement.

  10. Muscular Anatomy of the Human Ventricular Folds

    PubMed Central

    Moon, Jerald; Alipour, Fariborz

    2013-01-01

    Objective The purpose of this study was to better understand the muscular anatomy of the ventricular folds (VF) to help improve biomechanical modeling of phonation and to better understand the role of these muscles during phonatory and non-phonatory tasks. Method Four human larynges were decalcified and sectioned coronally from the posterior to anterior using a CryoJane tape transfer system, and stained using Massons trichrome. The total and relative area of muscles observed in each section were calculated and used for characterizing muscle distribution within the ventricular folds. Results The ventricular folds of the larynges contained anteriorly coursing thyroarytenoid and ventricularis muscle fibers lying in the lower half of the VF posteriorly, with some ventricularis muscle evident in the upper and lateral portion of the fold more anteriorly. Very little muscle tissue was observed in the medial half of the fold, and the anterior half of the VF was largely devoid of any muscle tissue. All four VF’s contained muscle bundles coursing superiorly and medially through the upper half of the fold toward the lateral margin of the epiglottis. Conclusions While variability in expression was evident, the well-defined thyroarytenoid muscle was readily apparent lateral to the arytenoid cartilage in all specimens. PMID:24224399

  11. Quantitative cineangiographic analysis of ventricular volume and mass in patients with single ventricle: relation to ventricular morphologies.

    PubMed

    Sano, T; Ogawa, M; Yabuuchi, H; Matsuda, H; Nakano, S; Shimazaki, Y; Taniguchi, K; Arisawa, J; Hirose, H; Kawashima, Y

    1988-01-01

    With the use of biplane selective ventriculography, the ventricular volume, ejection fraction, and ventricular mass were evaluated in 28 patients with a single ventricle, and those with the left ventricular type (LV type, 12 patients) and right ventricular type (RV type, 16 patients) were compared. There were no significant differences in terms of age, hemoglobin, systemic oxygen saturation, or pulmonary-to-systemic flow ratio in the two groups. No patients with atrioventricular valve regurgitation were included. The ventricular cavity volume was calculated by the area-length method. The ventricular mass volume was determined as the shell volume created by subtracting the ventricular cavity volume from the total ventricular volume calculated by adding the free wall thickness to the chamber dimensions. The ventricular mass volume was converted to mass by multiplying by the gravity of the heart muscle. There was no significant difference between patients with the LV type and RV type of single ventricle with respect to the end-diastolic ventricular volume (188 +/- 53 and 179 +/- 61 ml/m2 in LV and RV types, respectively), end-systolic volume (88 +/- 31 and 84 +/- 27 ml/m2), or ejection fraction (0.54 +/- 0.06 and 0.52 +/- 0.06).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3335072

  12. Enzyme polymorphisms in Canarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fifty-two accessions of Canarium involving seven species, C. ovatum, C. album, C. megalanthum, C. harveyi, C. indicum, C. mehenbethene, and C. odontophyllum were studied for isozyme polymorphisms. Starch gel electrophoresis with a histidine-citrate buffer system (pH 6.5) was employed to assay six en...

  13. Polymorphous Perversity in Texts

    ERIC Educational Resources Information Center

    Johnson-Eilola, Johndan

    2012-01-01

    Here's the tricky part: If we teach ourselves and our students that texts are made to be broken apart, remixed, remade, do we lose the polymorphous perversity that brought us pleasure in the first place? Does the pleasure of transgression evaporate when the borders are opened?

  14. Polymorphism of sorbitol

    NASA Astrophysics Data System (ADS)

    Nezzal, Amale; Aerts, Luc; Verspaille, Marleen; Henderickx, Geert; Redl, Andreas

    2009-07-01

    The polymorphism of sorbitol was investigated, confirming the existence of four anhydrous crystalline phases plus the hydrate. The crystallised melt (CM), the alpha form, and the gamma form were obtained via a dry route. The CM was confirmed to be a crystalline state with a spherulite morphology. The alpha form was obtained via direct conversion from the CM, in contrast to more complicated routes previously reported, and was found to have a very high crystallinity. Gamma crystals were obtained by seeding the melt at high temperature; however, crystallinity was clearly less than for alpha crystals. Despite its lower crystallinity, the gamma polymorph was found to be the most stable of the anhydrous crystalline forms; this was confirmed by its high melting point and low hygroscopicity. In contrast, the alpha polymorph has a relatively high melting point but lacks moisture stability at high relative humidity. The hydrate form has the same resistance to moisture as the gamma form, but melts at a lower temperature. The combination of both a high melting point and high stability in the presence of water makes the gamma polymorph best suited for confectionary applications.

  15. Investigation of Uranium Polymorphs

    SciTech Connect

    Sweet, Lucas E.; Henager, Charles H.; Hu, Shenyang Y.; Johnson, Timothy J.; Meier, David E.; Peper, Shane M.; Schwantes, Jon M.

    2011-08-01

    The UO3-water system is complex and has not been fully characterized, even though these species are common throughout the nuclear fuel cycle. As an example, most production schemes for UO3 result in a mixture of up to six or more different polymorphic phases, and small differences in these conditions will affect phase genesis that ultimately result in measureable changes to the end product. As a result, this feature of the UO3-water system may be useful as a means for determining process history. This research effort attempts to better characterize the UO3-water system with a variety of optical techniques for the purpose of developing some predictive capability for estimating process history in polymorphic phases of unknown origin. Three commercially relevant preparation methods for the production of UO3 were explored. Previously unreported low temperature routes to β- and γ-UO3 were discovered. Raman and fluorescence spectroscopic libraries were established for pure and mixed polymorphic forms of UO3 in addition to the common hydrolysis products of UO3. An advantage of the sensitivity of optical fluorescence microscopy over XRD has been demonstrated. Preliminary aging studies of the α and γ forms of UO3 have been conducted. In addition, development of a 3-D phase field model used to predict phase genesis of the system was initiated. Thermodynamic and structural constants that will feed the model have been gathered from the literature for most of the UO3 polymorphic phases.

  16. Incessant slow bundle branch reentrant ventricular tachycardia in a young patient with left ventricular noncompaction.

    PubMed

    Barra, Sérgio; Moreno, Nuno; Providência, Rui; Gonçalves, Helena; Primo, João José

    2013-06-01

    A 15-year-old girl was admitted to the cardiology outpatient clinic due to mild palpitations and documented incessant slow ventricular tachycardia (VT) with left bundle branch block (LBBB) pattern. The baseline electrocardiogram revealed first-degree atrioventricular block and intraventricular conduction defect. Transthoracic echocardiography showed prominent trabeculae and intertrabecular recesses suggesting left ventricular noncompaction (LVNC), which was confirmed by cardiac magnetic resonance imaging. During electrophysiological study, a sustained bundle branch reentrant VT with LBBB pattern and cycle length of 480 ms, similar to the clinical tachycardia, was easily and reproducibly inducible. As there was considerable risk of need for chronic ventricular pacing following right bundle ablation, no ablation was attempted and a cardioverter-defibrillator was implanted. To the best of our knowledge, no case reports of BBR-VT as the first manifestation of LVNC have been published. Furthermore, this is an extremely rare presentation of BBR-VT, which is usually a highly malignant arrhythmia.

  17. Amiodarone for the treatment and prevention of ventricular fibrillation and ventricular tachycardia

    PubMed Central

    Van Herendael, Hugo; Dorian, Paul

    2010-01-01

    Amiodarone has emerged as the leading antiarrhythmic therapy for termination and prevention of ventricular arrhythmia in different clinical settings because of its proven efficacy and safety. In patients with shock refractory out-of-hospital cardiac arrest and hemodynamically destabilizing ventricular arrhythmia, amiodarone is the most effective drug available to assist in resuscitation. Although the superiority of the transvenous implantable cardioverter defibrillator (ICD) over amiodarone has been well established in the preventive treatment of patients at high risk of life-threatening ventricular arrhythmias, amiodarone (if used with a beta-blocker) is the most effective antiarrhythmic drug to prevent ICD shocks and treat electrical storm. Both the pharmacokinetics and the electrophysiologic profile of amiodarone are complex, and its optimal and safe use requires careful patient surveillance with respect to potential adverse effects. PMID:20730062

  18. 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.

  19. Polymorphism of 4-bromobenzophenone.

    PubMed

    Strzhemechny, Mikhail A; Baumer, Vyacheslav N; Avdeenko, Anatoli A; Pyshkin, Oleg S; Romashkin, Roman V; Buravtseva, Lyubov M

    2007-04-01

    A combination of single-crystal and powder X-ray diffractometry was used to study the structure of two polymorphs of 4-bromobenzophenone over the temperature range from 100 to 300 K. One of the polymorphs of the title compound was known previously and its structure has been determined at room temperature [Ebbinghaus et al. (1997). Z. Kristallogr. 212, 339-340]. Two crystal growth methods were employed, one of which (a modification of the Bridgman-Stockbarger technique) resulted in single crystals of a previously unknown structure. The basic physical properties of the stable polymorph are: growth method, from 2-propanol solutions or gradient sublimation; space group, monoclinic P2(1)/c; melting point, T(m) = 355.2 K; X-ray density (at 100 K), D(x) = 1.646 g cm(-3). The same properties of the metastable polymorph (triclinic P\\overline 1 ) are: growth method, modified Bridgman-Stockbarger method; X-ray density (at 100 K), D(x) = 1.645 g cm(-3); T(m) = 354 K. Thermograms suggest that the melting of the metastable form is accompanied by at least a partial crystallization presumably into the monoclinic form; the transformation is therefore monotropic. Analysis of short distances in both polymorphs shows that numerous weak hydrogen bonds of the C-H...pi type ensure additional stabilization within the respective planes normal to the longest dimension of the molecules. The strong temperature dependence of the lattice constants and of the weak bond distances in the monoclinic form suggest that the weak bond interactions might be responsible for both the large thermal expansion within plane bc and the considerable thermal expansion anisotropy. PMID:17374940

  20. Assessment and management of right ventricular failure in left ventricular assist device patients.

    PubMed

    Holman, William L; Acharya, Deepak; Siric, Franjo; Loyaga-Rendon, Renzo Y

    2015-01-01

    Mechanical circulatory support devices, including ventricular assist devices (VADs) and the total artificial heart, have evolved to become accepted therapeutic options for patients with severe congestive heart failure. Continuous-flow left VADs are the most prevalent option for mechanical circulatory assistance and reliably provide years of support. However, problems related to acute and chronic right heart failure in patients with left VADs continue to cause important mortality and morbidity. This review discusses the assessment and management of right ventricular failure in left VAD patients. The goal is to summarize current knowledge and suggest new approaches to managing this problem.

  1. Induction of ventricular collapse by an axial flow blood pump.

    PubMed

    Amin, D V; Antaki, J F; Litwak, P; Thomas, D; Wu, Z J; Watach, M

    1998-01-01

    An important consideration for clinical application of rotary blood pump based ventricular assist is the avoidance of ventricular collapse due to excessive operating speed. Because healthy animals do not typically demonstrate this phenomenon, it is difficult to evaluate control algorithms for avoiding suction in vivo. An acute hemodynamic study was thus conducted to determine the conditions under which suction could be induced. A 70 kg calf was implanted with an axial flow assist device (Nimbus/UoP IVAS; Nimbus Inc., Rancho Cordova, CA) cannulated from the left ventricular apex to ascending aorta. On initiation of pump operation, several vasoactive interventions were performed to alter preload, afterload, and contractility of the left ventricle. Initially, dobutamine increased contractility and heart rate ([HR] = 139; baseline = 70), but ventricular collapse was not achievable, even at the maximal pump speed of 15,000 rpm. Norepinephrine decreased HR (HR = 60), increased contractility, and increased systemic vascular resistance ([SVR] = 24; baseline = 15), resulting in ventricular collapse at a pump speed of 14,000 rpm. Isoproterenol (beta agonist) increased HR (HR = 103) and decreased SVR (SVR = 12), but ventricular collapse was not achieved. Inferior vena cava occlusion reduced preload, and ventricular collapse was achieved at speeds as low as 11,000 rpm. Esmolol (beta1 antagonist) decreased HR (HR = 55) and contractility, and ventricular collapse was achieved at 11,500 rpm. Episodes of ventricular collapse were characterized initially by the pump output exceeding the venous return and the aortic valve remaining closed throughout the cardiac cycle. If continued, the mitral valve would remain open throughout the cardiac cycle. Using these unique states of the mitral and aortic valves, the onset of ventricular collapse could reliably be identified. It is hoped that the ability to detect the onset of ventricular collapse, rather than the event itself, will assist in

  2. Right ventricular function before and after percutaneous balloon mitral valvuloplasty.

    PubMed

    Burger, W; Brinkies, C; Illert, S; Teupe, C; Kneissl, G D; Schräder, R

    1997-01-01

    Aim of this study was to evaluate right ventricular performance in patients with mitral stenosis and its modification by balloon valvuloplasty. Right ventricular volumes of 24 patients with postrheumatic mitral stenosis were determined by thermodilution 1 or 2 days before and 1 or 2 days after valvuloplasty. Right ventricular ejection fraction at rest was 43 (36-47)% (median and interquartile range). Right ventricular end-diastolic volume was 100 (86-119) ml/m2. Supine bicycle exercise (50 Watt) reduced right ventricular ejection fraction to 30 (29-37)% (P < 0.0001) and increased right ventricular end-diastolic volume to 124 (112-141) ml/m2 (P < 0.0001). At rest, right ventricular ejection fraction correlated inversely with pulmonary vascular resistance (r = -0.64, P < 0.0001), while no significant correlation with mitral valve area was found. Valvuloplasty increased right ventricular ejection fraction at rest to 48 (44-50)% (P < 0.005), and during exercise to 42 (38-45)% (P < 0.0001). This improvement of right ventricular ejection fraction correlated inversely with the value of this parameter before valvuloplasty (r = -0.88, P < 0.0001) and with the gain in stroke volume (r = 0.57, P < 0.01). The right ventricular function curve, disturbed before commissurotomy, was reestablished by the procedure. In conclusion, at the here investigated stage of mitral stenosis right ventricular function is reversibly impaired. This is predominantly caused by the hemodynamic consequences of the valvular defect and not by an impairment of right ventricular myocardial function.

  3. [Ventricular fibrillation following hyperventilation and apneic underwater swimming].

    PubMed

    Antonelli, Dante; Freedberg, Nahum A; Turgeman, Yoav

    2014-10-01

    This is a case study of an 18 years old boy who lost consciousness during apneic underwater swimming. When cardiopulmonary resuscitation was initiated ventricular fibrillation was seen on cardiac monitoring. Bradycardia, atrial and ventricular premature beats are a known response to hyperventilation and apneic underwater diving. This case is the first documentation of ventricular fibritllation as a cause of sudden cardiac death during apneic underwater swimming.

  4. A porcine model for acute ischaemic right ventricular dysfunction

    PubMed Central

    Haraldsen, Pernille; Lindstedt, Sandra; Metzsch, Carsten; Algotsson, Lars; Ingemansson, Richard

    2014-01-01

    OBJECTIVES To establish an experimental model for acute ischaemic isolated right ventricular dysfunction and the subsequent haemodynamic changes. METHODS An open-chest porcine model with ischaemic dysfunction of the right ventricle induced by ligation of the three main branches supporting the right ventricular free wall. Invasive monitoring of mean arterial blood pressure (MAP), central venous pressure (CVP), left atrial pressure (LAP) and right ventricular pressure (RVP); ultrasonic measurement of cardiac output (CO) and calculation of haemodynamic parameters such as stroke volume (SV), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and right ventricular stroke work (RVSW) using standard formulae. RESULTS The ischaemic challenge to the right ventricle resulted in a significant (≥30%) reduction in RVSW associated with an increase (6–25%) in CVP and reduction (8–18%) in pulmonary artery pressure (PAP) despite unchanged PVR, all reflecting the failing right ventricle. There was also a significant drop in CO (14–22%) despite unchanged LAP indicating lessened transpulmonary delivery of left ventricular preload due to the failing right ventricle causing the haemodynamic compromise rather than left ventricular failure. Supraventricular and ventricular arrhythmias occurred in three and two out of seven pigs, respectively—all of which except one were successfully resuscitated with cardioversion and/or defibrillation. CONCLUSIONS This novel open-chest porcine model of induced ischaemia of the right ventricular free wall resulted in significant haemodynamic compromise confirmed using standard haemodynamic measurements making it useful for further research on acute, ischaemic isolated right ventricular failure. PMID:24092465

  5. Predicting utility of exercise tests based on history/holter in patients with premature ventricular contractions.

    PubMed

    Robinson, Brad; Xie, Li; Temple, Joel; Octavio, Jenna; Srayyih, Maytham; Thacker, Deepika; Kharouf, Rami; Davies, Ryan; Gidding, Samuel S

    2015-01-01

    Premature ventricular contractions (PVCs) are considered benign in patients with structurally normal hearts, particularly if they suppress with exercise. Catecholaminergic polymorphic ventricular tachycardia (CPVT) requires exercise testing to unmask the malignant phenotype. We studied risk factors and Holter monitor variables to help predict the necessity of exercise testing in patients with PVCs. We retrospectively reviewed 81 patients with PVCs that suppressed at peak exercise and structurally normal hearts referred to the exercise laboratory in 2011. We reviewed 11 patients from 2003 to 2012 whose PVCs were augmented at peak exercise (mean age 13 ± 4 years; 52 % male, 180 exercise studies). We recorded clinical risk factors and comorbidities (family history of arrhythmia or sudden unexpected death [SUD], presence of syncope) and Holter testing parameters. Family history of VT or SUD (P = 0.011) and presence of VT on Holter (P = 0.011) were significant in predicting failure of PVCs to suppress at peak heart rate on exercise testing. Syncope was not statistically significant in predicting suppression (P = 0.18); however, CPVT was diagnosed in four patients with syncope during exercise. Quantity of PVCs, Lown grade, couplets on Holter, monomorphism, and PVC elimination at peak heart rate on Holter were not predictors of PVC suppression on exercise testing. Patients with syncope during exercise, family history of arrhythmia or SUD, or a Holter monitor showing VT warrant exercise testing to assess for CPVT.

  6. 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

  7. B-Type Natriuretic Peptide Levels Predict Ventricular Arrhythmia Post Left Ventricular Assist Device Implantation.

    PubMed

    Hellman, Yaron; Malik, Adnan S; Lin, Hongbo; Shen, Changyu; Wang, I-Wen; Wozniak, Thomas C; Hashmi, Zubair A; Pickrell, Jeanette; Jani, Milena; Caccamo, Marco A; Gradus-Pizlo, Irmina; Hadi, Azam

    2015-12-01

    B-type natriuretic peptide (BNP) levels have been shown to predict ventricular arrhythmia (VA) and sudden death in patients with heart failure. We sought to determine whether BNP levels before left ventricular assist device (LVAD) implantation can predict VA post LVAD implantation in advanced heart failure patients. We conducted a retrospective study consisting of patients who underwent LVAD implantation in our institution during the period of May 2009-March 2013. The study was limited to patients receiving a HeartMate II or HeartWare LVAD. Acute myocardial infarction patients were excluded. We compared between the patients who developed VA within 15 days post LVAD implantation to the patients without VA. A total of 85 patients underwent LVAD implantation during the study period. Eleven patients were excluded (five acute MI, four without BNP measurements, and two discharged earlier than 13 days post LVAD implantation). The incidence of VA was 31%, with 91% ventricular tachycardia (VT) and 9% ventricular fibrillation. BNP remained the single most powerful predictor of VA even after adjustment for other borderline significant factors in a multivariate logistic regression model (P < 0.05). BNP levels are a strong predictor of VA post LVAD implantation, surpassing previously described risk factors such as age and VT in the past. PMID:25864448

  8. Catheter ablation for ventricular tachyarrhythmias in patients supported by continuous-flow left ventricular assist devices.

    PubMed

    Garan, Arthur R; Iyer, Vivek; Whang, William; Mody, Kanika P; Yuzefpolskaya, Melana; Colombo, Paolo C; Te-Frey, Rosie; Takayama, Hiroo; Naka, Yoshifumi; Garan, Hasan; Jorde, Ulrich P; Uriel, Nir

    2014-01-01

    Ventricular arrhythmias (VAs) are common after implantation of a left ventricular assist device (LVAD) and in a subset of patients may be refractory to medication. Morbidity from VA in this population includes right ventricular failure (RVF). We sought to evaluate the efficacy of catheter ablation for VA in patients with LVAD. A retrospective analysis of patients supported by continuous-flow LVAD referred for catheter ablation of ventricular tachycardia (VT) between 2008 and the present was performed. Seven patients were referred for VT ablation an average of 236 ± 292 days after LVAD implantation. Three patients (42.9%) developed RVF in the setting of intractable arrhythmias. A transfemoral approach was used for six patients (85.7%) and an epicardial for one patient (14.3%). The clinical VT was inducible and successfully ablated in six patients (85.7%). The location of these arrhythmias was apical in three cases (42.9%). A total of 13 VTs were ablated in seven patients. Although the majority had reduction in VA frequency, recurrent VAs were observed in six patients (85.7%). One patient (14.3%) experienced a bleeding complication after the procedure. For patients with a high VA burden after LVAD implantation, VT ablation is safe and feasible, but VA frequently recurs.

  9. Conduction defects, ventricular arrhythmias, and late death after surgical closure of ventricular septal defect.

    PubMed Central

    Blake, R S; Chung, E E; Wesley, H; Hallidie-Smith, K A

    1982-01-01

    One hundred and eighty-seven patients who had surgical closure of a ventricular septal defect between 1958 and 1975 were followed for up to 21 years. there were 17 late sudden deaths of which eight occurred in completely fit patients while nine were already under medical care. In an attempt to elucidate possible risk factors and reoperative and serial postoperative electrocardiograms of all patients were studied. Fifty-one unselected healthy follow-up patients agreed to 24 hour ambulatory monitoring. Progressive exercise testing (Bruce protocol) was carried out on 31 of them and an additional seven patients. There was a significant correlation between recorded ventricular arrhythmias and conduction defects, particularly progressive conduction defects. Transient complete heart block carried a bad prognosis and grade 3-4b ventricular arrhythmias were a major risk factor and recorded in 10 of the 17 patients who died. Long-term postoperative electrocardiographic follow-up is recommended and 24 hour ambulatory monitoring and exercise testing complement the findings of the resting electrocardiogram. The long-term treatment of survivors found to have ventricular arrhythmias must be considered. PMID:7066115

  10. Hemodynamic effects of encainide in patients with ventricular arrhythmia and poor ventricular function

    SciTech Connect

    Sami, M.H.; Derbekyan, V.A.; Lisbona, R.

    1983-09-01

    Gated cardiac scanning was used to evaluate the hemodynamic effects of encainide in 19 patients (1 woman) with complex ventricular arrhythmia and depressed left ventricular (LV) function (ejection fraction less than 45%). Patients were 36 to 80 years old (average 61). All were candidates for long-term encainide therapy after having failed with currently available antiarrhythmics. Sixty-three percent had congestive heart failure before they received encainide. All were evaluated in the hospital before encainide therapy by a gated cardiac scan performed at least 3 days after discontinuing all antiarrhythmic drugs. Patients received oral encainide in doses of 75 to 200 mg. Gated cardiac scans were repeated 1 to 2 weeks later when an 80% reduction in frequency of premature ventricular complexes was observed on a 24-hour Holter recording. No patient had worsening of congestive heart failure during encainide therapy. Encainide did not significantly affect ejection fraction, which averaged 22 +/- 10% before and 25 +/- 14% (SD) after encainide (difference not significant (NS)). Other hemodynamic variables, including heart rate, blood pressure, stroke volume and end-diastolic volume, remained unchanged during encainide therapy. Digoxin blood levels in 10 patients averaged 1.04 +/- 0.43 before and 1.22 +/- 0.47 mg/ml (NS) during encainide therapy. Thus, encainide given orally in clinically effective doses does not appear to have significant hemodynamic effects in patients with ventricular arrhythmia and depressed LV function.

  11. Polymorphism of phosphoric oxide

    USGS Publications Warehouse

    Hill, W.L.; Faust, G.T.; Hendricks, S.B.

    1943-01-01

    The melting points and monotropic relationship of three crystalline forms of phosphoric oxide were determined by the method of quenching. Previous vapor pressure data are discussed and interpreted to establish a pressure-temperature diagram (70 to 600??) for the one-component system. The system involves three triple points, at which solid, liquid and vapor (P4O10) coexist in equilibrium, namely: 420?? and 360 cm., 562?? and 43.7 cm. and 580?? and 55.5 cm., corresponding to the hexagonal, orthorhombic and stable polymorphs, respectively, and at least two distinct liquids, one a stable polymer of the other, which are identified with the melting of the stable form and the hexagonal modification, respectively. Indices of refraction of the polymorphs and glasses were determined. The density and the thermal, hygroscopic and structural properties of the several phases are discussed.

  12. [Polymorphs of clopidogrel bisulfate].

    PubMed

    Liu, Yi; Huang, Hai-Wei; Wu, Jian-Min; Shi, Ya-Qin; Yang, La-Hu

    2013-08-01

    This paper is to report the polymorphism of raw materials of clopidogrel bisulfate at home and abroad. By the analysis of Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (p-XRD), samples are roughly classified into two groups, except one patent material. And the differential scanning calorimeter (DSC) examination showed more detailed information for these materials. The results of the study could provide comprehensive basis for the quality evaluation of clopidogrel bisulfate. PMID:24187849

  13. Effects of bepridil on ventricular depolarization and repolarization of rabbit isolated hearts with particular reference to its possible proarrhythmic properties.

    PubMed Central

    Osaka, T.; Kodama, I.; Toyama, J.; Yamada, K.

    1988-01-01

    1. Effects of bepridil on ventricular depolarization and repolarization sequences were examined in rabbit Langendorff-perfused hearts. 2. In distant bipolar electrograms (DBEs), bepridil, 10(-6) M, caused a significant prolongation of QT intervals. At 10(-5) M, the QT prolongation was further enhanced, and a significant prolongation of QRS duration was also observed. Polymorphous ventricular tachycardia was frequently induced by a single premature stimulus at the higher concentration. 3. In epicardial electrograms recorded through modified bipolar electrodes, bepridil, 10(-6) M, prolonged the interval from the peak negative deflection of the QRS complex to the apex of the T wave (Q-aT), which corresponded to the intracellular action potential duration at 90% repolarization (APD90). The Q-aT prolongation was larger in the base than in the apex, resulting in a marked distortion and dispersion of repolarization. The epicardial activation sequence was unaffected. 4. At 10(-5) M bepridil, the dispersion of repolarization was much more enhanced by activation delay in the epicardial surface. 5. These findings suggest that bepridil causes regionally different lengthening of APD in ventricular muscle leading to an increase in temporal dispersion of repolarization, and that this dispersion may be inducive for re-entrant arrhythmias when accompanied by slow conduction at toxic doses. PMID:3260528

  14. Ventricular shunt infections: immunopathogenesis and clinical management.

    PubMed

    Gutierrez-Murgas, Yenis; Snowden, Jessica N

    2014-11-15

    Ventricular shunts are the most common neurosurgical procedure performed in the United States. This hydrocephalus treatment is often complicated by infection of the device with biofilm-forming bacteria. In this review, we discuss the pathogenesis of shunt infection, as well as the implications of the biofilm formation on treatment and prevention of these infections. Many questions remain, including the contribution of glia and the impact of inflammation on developmental outcomes following infection. Immune responses within the CNS must be carefully regulated to contain infection while minimizing bystander damage; further study is needed to design optimal treatment strategies for these patients.

  15. [Recurrent failed ICD therapy of ventricular tachycardia].

    PubMed

    Hein, W; Ellringmann, U; Vollmann, D; Rostock, T; Schott, P

    2012-11-01

    Implantable cardioverter defibrillators (ICD) are used as standard therapy to prevent sudden cardiac death in heart failure patients. Today, physicians in emergency and intensive care medicine are often confronted with problems of ICD therapy in these patients. We report a case of a patient suffering from recurrent ventricular tachycardia (VT) requiring antiarrhythmia treatment with amiodarone. With an increasing drug loading, the VT cycle length was progressively prolonged resulting in a slow VT undetectable for the ICD. Subsequently, the patient was scheduled for VT ablation after which the patient became free of arrhythmia recurrences. PMID:23070331

  16. Left ventricular assist device management and complications.

    PubMed

    Birati, Edo Y; Rame, J Eduardo

    2014-07-01

    Patients on long-term left ventricular assist device (LVAD) support present unique challenges in the intensive care unit. It is crucial to know the status of end-organ perfusion, which may require invasive hemodynamic monitoring with a systemic arterial and pulmonary artery catheter. Depending on the indication for LVAD support (bridge to decision or cardiac transplantation vs destination therapy), it is important to readdress goals of care with the patient (if possible) and their family after major events have occurred that challenge the survival of the patient. PMID:24996611

  17. A Randomized Controlled Trial:Treatments on Infundibular Ventricular Septal Defect

    ClinicalTrials.gov

    2015-02-06

    Heart Septal Defects, Ventricular; Double Outlet Right Ventricle, Noncommitted VSD; Double Outlet Right Ventricle, Subaortic VSD; Double Outlet Right Ventricle, Subpulmonary VSD; Supracristal Ventricular Septal Defect

  18. Echocardiographic assessment of ejection fraction in left ventricular hypertrophy

    PubMed Central

    Wandt, B; Bojo, L; Tolagen, K; Wranne, B

    1999-01-01

    OBJECTIVE—To investigate the value of Simpson's rule, Teichholz's formula, and recording of mitral ring motion in assessing left ventricular ejection fraction (EF) in patients with left ventricular hypertrophy.
DESIGN—Left ventricular ejection fraction calculated by Simpson's rule and by Techholz's formula and estimated by mitral ring motion was compared with values obtained by radionuclide angiography.
SETTING—Secondary referral centre.
PATIENTS—16 patients with left ventricular hypertrophy and a clinical diagnosis of hypertrophic cardiomyopathy or hypertension.
RESULTS—Calculation by Teichholz's formula overestimated left ventricular ejection fraction by 10% (p = 0.002) and estimation based on mitral ring motion—that is, long axis measurements—underestimated ejection fraction by 19% (p = 0.002), without significant correlation between ring motion and ejection fraction. There was no significant difference between mean values of ejection fraction calculated by Simpson's rule and measured by the reference method, but a considerable scatter about the regression line with a standard error of the estimate of 9.3 EF%.
CONCLUSIONS—In patients with left ventricular hypertrophy the ejection fraction, calculated by Teichholz's formula or Simpson's rule, is a poor measure of left ventricular function. When mitral ring motion is used for the assessment in these patients the function should be expressed in ways other than by the ejection fraction.


Keywords: left ventricular hypertrophy; ejection fraction; mitral ring motion; atrioventricular plane displacement PMID:10409535

  19. Right ventricular dysfunction in patients with septic shock.

    PubMed

    Dhainaut, J F; Lanore, J J; de Gournay, J M; Huyghebaert, M F; Brunet, F; Villemant, D; Monsallier, J F

    1988-01-01

    Using a rapid computerized thermodilution method, we examined the evolution of right ventricular performance in 23 patients with septic shock. Nine survived the episode of septic shock. The other 14 patients died of refractory circulatory shock. Significant right ventricular systolic dysfunction, defined as decreased ejection fraction (-39%) and right ventricular dilation (+38%) was observed in all patients with septic shock. However, in the survivors, increased right ventricular preload may prevent hemodynamic evidence of right ventricular pump failure by utilizing the Frank-Starling mechanism to maintain stroke volume. Conversely, in the nonsurvivors, right ventricular dysfunction was more prononced two days after the onset of septic shock, leading to a fall in stroke. In the last patients, a decrease in contractility appears to be the major factor accounting for decreased right ventricular performance, as evidenced by the marked increase in end-systolic volume (+27%) without significant change in pulmonary artery pressure, during the later stage of septic shock. The observed right ventricular pump failure then appears associated with an alteration in diastolic mechanical properties of this ventricle, as suggested by a leftward displacement of the individual pressure-volume curves. PMID:3403793

  20. Bradyarrhythmias: first presentation of arrhythmogenic right ventricular cardiomyopathy?

    PubMed

    Burghouwt, Danielle E; Kammeraad, Janneke Ae; Knops, Paul; du Plessis, Frederik A; de Groot, Natasja Ms

    2015-04-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disorder characterized by progressive replacement of myocardial cells by fibro-fatty tissue giving rise to ventricular tachyarrhythmias. In this case report, we describe a pediatric patient with sinoatrial arrests and second degree atrioventricular conduction block several years before ARVC became apparent. These findings suggest that bradyarrhythmias can also be the first expression of ARVC.

  1. Aortic coarctation, aneurysm, and ventricular dysfunction in an asymptomatic infant.

    PubMed

    García, Ana I; Aguilar, Juan M; García, Enrique

    2016-06-01

    Aortic arch coarctation with post-coarctation aneurysm is rare in infants. We present the case of an asymptomatic 3-month-old infant with severe left ventricular dysfunction in this setting. The patient underwent surgical repair, and the left ventricular ejection fraction improved to recovery the 4th post-operative month. PMID:26980403

  2. Left ventricular guidewire pacing for transcatheter aortic valve implantation.

    PubMed

    Guérios, Enio E; Wenaweser, Peter; Meier, Bernhard

    2013-12-01

    Previous reports prove the safety and efficacy of cardiac pacing employing a guidewire in the left ventricle as unipolar pacing electrode. We describe the use of left ventricular guidewire pacing as an alternative to conventional transvenous temporary right ventricular pacing in the context of transcatheter aortic valve implantation.

  3. Aortic coarctation, aneurysm, and ventricular dysfunction in an asymptomatic infant.

    PubMed

    García, Ana I; Aguilar, Juan M; García, Enrique

    2016-06-01

    Aortic arch coarctation with post-coarctation aneurysm is rare in infants. We present the case of an asymptomatic 3-month-old infant with severe left ventricular dysfunction in this setting. The patient underwent surgical repair, and the left ventricular ejection fraction improved to recovery the 4th post-operative month.

  4. Arrhythmogenic right ventricular dysplasia/cardiomyopathy in a Siberian husky.

    PubMed

    Fernández del Palacio, M J; Bernal, L J; Bayón, A; Bernabé, A; Montes de Oca, R; Seva, J

    2001-03-01

    A seven-month-old male Siberian husky was presented with a recent history of anorexia, hindlimb weakness and syncope. Physical examination revealed severe tachycardia, tachypnoea and dyspnoea. Mucous membranes were pale and femoral pulses were weak. An electrocardiogram showed sustained ventricular tachycardia with a left bundle branch block configuration. Thoracic radiographs revealed slight right ventricular enlargement and two-dimensional echocardiography revealed mild right ventricular dilation at the cardiac apex and some hyperechogenic areas on the right side of the interventricular septum. Administration of intravenous lignocaine converted the ventricular tachycardia to sinus rhythm. The maintenance antiarrhythmic therapy consisted of oral procainamide and propranolol. Three weeks later the dog died suddenly. On postmortem examination, the right ventricular free wall was very thin at the apex, infundibulum and caudal aspect of the right ventricular parietal wall, similar to the 'triangle of dysplasia' of human patients. Histopathological examination revealed replacement of several areas of right ventricular free wall myocardium with connective tissue and fat. The right atrium and left ventricle were less severely affected by the same lesions. The clinical and pathological findings are similar to those reported in young people with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

  5. Rituximab-induced interleukin-15 reduction associated with clinical improvement in rheumatoid arthritis

    PubMed Central

    Díaz-Torné, César; Ortiz de Juana, M Angels; Geli, Carme; Cantó, Elisabet; Laiz, Ana; Corominas, Héctor; Casademont, Jordi; de Llobet, Josep M; Juárez, Cándido; Díaz-López, César; Vidal, Sílvia

    2014-01-01

    Rituximab therapy alters all aspects of B-cell participation in the disturbed immune response of rheumatoid arthritis patients. To determine the impact of B-cell depletion on other immune compartments, we analysed levels of soluble and surface interleukin-15 (IL-15) along with the frequency of IL-15-related subsets after rituximab treatment. We then studied the correlation of observed changes with clinical activity. Heparinized blood samples from 33 rheumatoid arthritis patients were collected on days 0, 30, 90 and 180 after each of three rituximab cycles. Serum cytokine levels were determined by ELISA. Interleukin-15 trans-presentation was analysed by cytometry. Flow cytometry with monoclonal antibodies was performed to analyse circulating cell subsets. Interleukin-15 was detected in the serum of 25 patients before initiating the treatment. Rituximab then progressively reduced serum IL-15 (138 ± 21 pg/ml at baseline, 48 ± 18 pg/ml after third cycle, P = 0·03) along with IL-17 (1197 ± 203 pg/ml at baseline, 623 ± 213 pg/ml after third cycle, P = 0·03) and tended to increase the frequency of circulating regulatory T cells (3·1 ± 1 cells/μl at baseline, 7·7 ± 2 cells/μl after third cycle). Rituximab also significantly decreased IL-15 trans-presentation on surface monocytes of patients negative for IL-15 serum (mean fluorescence intensity: 4·82 ± 1·30 at baseline, 1·42 ± 0·69 after third cycle P = 0·05). Reduction of serum IL-15 was associated with decrease in CD8+ CD45RO+/RA+ ratio (1·17 ± 0·21 at baseline, 0·36 ± 0·06 at third cycle, P = 0·02). DAS28, erythrocyte sedimentation rate and C-reactive protein correlated significantly with CD8+ CD45RO+/RA+ ratio (R = 0·323, R = 0·357, R = 0·369 respectively, P < 0·001). Our results suggest that sustained clinical improvement after rituximab treatment is associated with IL-15/memory T-cell-related mechanisms beyond circulating B cells. PMID:24219764

  6. Rituximab-induced depletion of anti-PLA2R autoantibodies predicts response in membranous nephropathy.

    PubMed

    Beck, Laurence H; Fervenza, Fernando C; Beck, David M; Bonegio, Ramon G B; Malik, Fahim A; Erickson, Stephen B; Cosio, Fernando G; Cattran, Daniel C; Salant, David J

    2011-08-01

    Autoantibodies to the M-type phospholipase A(2) receptor (PLA(2)R) are sensitive and specific for idiopathic membranous nephropathy. The anti-B cell agent rituximab is a promising therapy for this disease, but biomarkers of early response to treatment currently do not exist. Here, we investigated whether levels of anti-PLA(2)R correlate with the immunological activity of membranous nephropathy, potentially exhibiting a more rapid response to treatment than clinical parameters such as proteinuria. We measured the amount of anti-PLA(2)R using Western blot immunoassay in serial serum samples from a total of 35 patients treated with rituximab for membranous nephropathy in two distinct cohorts. Pretreatment samples from 25 of 35 (71%) patients contained anti-PLA(2)R, and these autoantibodies declined or disappeared in 17 (68%) of these patients within 12 months after rituximab. Those who demonstrated this immunologic response fared better clinically: 59% and 88% attained complete or partial remission by 12 and 24 months, respectively, compared with 0% and 33% among those with persistent anti-PLA(2)R levels. Changes in antibody levels preceded changes in proteinuria. One subject who relapsed during follow-up had a concomitant return of anti-PLA(2)R. In summary, measuring anti-PLA(2)R levels by immunoassay may be a method to follow and predict response to treatment with rituximab in membranous nephropathy.

  7. Rituximab-Induced Depletion of Anti-PLA2R Autoantibodies Predicts Response in Membranous Nephropathy

    PubMed Central

    Fervenza, Fernando C.; Beck, David M.; Bonegio, Ramon G.B.; Malik, Fahim A.; Erickson, Stephen B.; Cosio, Fernando G.; Cattran, Daniel C.; Salant, David J.

    2011-01-01

    Autoantibodies to the M-type phospholipase A2 receptor (PLA2R) are sensitive and specific for idiopathic membranous nephropathy. The anti-B cell agent rituximab is a promising therapy for this disease, but biomarkers of early response to treatment currently do not exist. Here, we investigated whether levels of anti-PLA2R correlate with the immunological activity of membranous nephropathy, potentially exhibiting a more rapid response to treatment than clinical parameters such as proteinuria. We measured the amount of anti-PLA2R using Western blot immunoassay in serial serum samples from a total of 35 patients treated with rituximab for membranous nephropathy in two distinct cohorts. Pretreatment samples from 25 of 35 (71%) patients contained anti-PLA2R, and these autoantibodies declined or disappeared in 17 (68%) of these patients within 12 months after rituximab. Those who demonstrated this immunologic response fared better clinically: 59% and 88% attained complete or partial remission by 12 and 24 months, respectively, compared with 0% and 33% among those with persistent anti-PLA2R levels. Changes in antibody levels preceded changes in proteinuria. One subject who relapsed during follow-up had a concomitant return of anti-PLA2R. In summary, measuring anti-PLA2R levels by immunoassay may be a method to follow and predict response to treatment with rituximab in membranous nephropathy. PMID:21784898

  8. Rituximab induces sustained reduction of pathogenic B cells in patients with peripheral nervous system autoimmunity

    PubMed Central

    Maurer, Michael A.; Rakocevic, Goran; Leung, Carol S.; Quast, Isaak; Lukačišin, Martin; Goebels, Norbert; Münz, Christian; Wardemann, Hedda; Dalakas, Marinos; Lünemann, Jan D.

    2012-01-01

    The B cell–depleting IgG1 monoclonal antibody rituximab can persistently suppress disease progression in some patients with autoimmune diseases. However, the mechanism underlying these long-term beneficial effects has remained unclear. Here, we evaluated Ig gene usage in patients with anti–myelin-associated glycoprotein (anti-MAG) neuropathy, an autoimmune disease of the peripheral nervous system that is mediated by IgM autoantibodies binding to MAG antigen. Patients with anti-MAG neuropathy showed substantial clonal expansions of blood IgM memory B cells that recognized MAG antigen. The group of patients showing no clinical improvement after rituximab therapy were distinguished from clinical responders by a higher load of clonal IgM memory B cell expansions before and after therapy, by persistence of clonal expansions despite efficient peripheral B cell depletion, and by a lack of substantial changes in somatic hypermutation frequencies of IgM memory B cells. We infer from these data that the effectiveness of rituximab therapy depends on efficient depletion of noncirculating B cells and is associated with qualitative immunological changes that indicate reconfiguration of B cell memory through sustained reduction of autoreactive clonal expansions. These findings support the continued development of B cell–depleting therapies for autoimmune diseases. PMID:22426210

  9. Rituximab-induced neutropenia in a patient with inflammatory myopathy and systemic sclerosis overlap disease

    PubMed Central

    Roberts, Mark; Oddis, Chester; Herrick, Arianne; Chinoy, Hector

    2016-01-01

    Rituximab (RTX) is a monoclonal chimeric antibody directed against the CD20 antigen of B lymphocytes. Late onset neutropenia (LON) is a recognised complication of rituximab usually occurring 4 weeks after the last dose and is reported in both haematological and rheumatological conditions. However, it has never been described in a patient with myositis and systemic sclerosis overlap disease. We describe a case of LON in a 54-year-old man who was diagnosed with myositis and then systemic sclerosis overlap disease. It resolved within 7 days, and the patient did not suffer neutropenic sepsis or any other complications. We propose similar mechanisms for LON as described in other conditions and routine blood monitoring in such patients. PMID:27407275

  10. Ultrasonic Sensors For Measuring Regional Ventricular Function

    NASA Astrophysics Data System (ADS)

    Hartley, C. J.; Rabinovitz, R. S.; Patel, B.; Suignard, L. J.; Litowitz, H.; Chelly, J. E.; Jeroudi, M. O.; Charlat, M. L.; O'Neill, P. G.; Noon, G. P.

    1988-04-01

    Measurement of systolic wall thickening by sonomicrometry is an accurate index of regional left ventricular (LV) function, but the trauma of crystal inserion precludes its clinical use. We have developed a 4-mm 10 MHz ultrasonic probe which can either be sutured or applied via suction to the epicar-diuui and can measure wall thickening at anv depth of the LV wall. In 18 dogs, the suction probe correlated well (r=0.97) with previously validated sutured probe. To assess clinical feasibility, the probe was applied to the epicardium of 45 patients undergoing coronary bypass surgery. Good wall thickening tracings were obtained with no trauma. Transmural LV thickening fraction prior to bypass surgery was 32 ± 6 % (X ± SEM) at the midventricular lateral wall, 29 ± 5 % at the anterior basal wall and 25 ± 5 % at the midventricular posterior wall. Right ventricular thickening fraction averaged 25 ± 4 %. In general, wall thickening during immediate postoperative period remained unchanged compared to preoperative thickening fraction. Exteriorization of a wire attached to the sutured probe allows in situ monitoring of wall thickening for 48-72 h after surgery and subsequent removal. Thus, this probe is an accurate, atraumatic method for measuring right and LV regional function. Transmural, endocardial and epicardial function can be mapped at various sites during surgery and post-operatively one can follow serial changes of regional function and assess the effects of cardioplegia and other therapeutic interventions.

  11. ECG manifestations of left ventricular electrical remodeling.

    PubMed

    Estes, E Harvey

    2012-01-01

    Research and thinking about the electrocardiographic manifestations of left ventricular hypertrophy has been constrained by a limited conceptual model of the process: heart disease produces chamber enlargement (increased mass), which in turn produces an altered electrocardiogram. The process is much more complex than can be represented in this simple model. A more robust and intricate model is proposed, in which heart (and vascular) disease causes structural changes, electrical changes, biochemical changes, and others, all of which interact to produce electrical remodeling of ventricular myocardium. This electrical remodeling results in a variety of ECG changes. All of these changes interact, leading to an altered clinical course, and to premature death. It is suggested that research, based on this model, can provide new clues to the processes involved, and improve the prediction of clinical outcomes. New directions in research, in recording equipment, and in organizational activities are suggested to test this new model, and to improve the usefulness of the electrocardiogram as a research and diagnostic tool.

  12. The electrocardiographic diagnosis of intraventricular blocks coexisting with ventricular preexcitation.

    PubMed

    Chiale, Pablo A; Elizari, Marcelo V

    2012-09-01

    The electrocardiographic diagnosis of intraventricular conduction disturbances may be hindered by the coexistence of ventricular preexcitation. In fact, the premature depolarization of ventricular myocardium through an accessory pathway tends to conceal any electrocardiographic manifestation of a bundle-branch block. However, there are several conditions favoring the diagnosis of bundle-branch block associated with ventricular preexcitation: intermittency of ventricular preexcitation and/or bundle-branch block, fast atrioventricular (AV) nodal impulse propagation, slow conduction over the accessory pathway or between its ventricular insertion site and the remaining myocardium, and presence of atrioventricular junctional ectopic beats exposing the intraventricular conduction disturbance. This article reexamines the available data on preexcitation in patients with intraventricular blocks and presents clinical examples to emphasize the importance of a thorough examination of the electrocardiogram to attain the correct diagnosis of this association.

  13. Left Ventricular Assist Device Implantation After Intracardiac Parachute Device Removal.

    PubMed

    Abu Saleh, Walid K; Al Jabbari, Odeaa; Bruckner, Brian A; Suarez, Erik E; Estep, Jerry D; Loebe, Matthias

    2015-08-01

    Left ventricular assist device implantation is a proven and efficient modality for the treatment of end-stage heart failure. Left ventricular assist device versatility as a bridge to heart transplantation or destination therapy has led to improved patient outcomes with a concomitant rise in its overall use. Other less invasive treatment modalities are being developed to improve heart function and morbidity and mortality for the heart failure population. Percutaneous ventricular restoration is a new investigational therapy that deploys an intracardiac parachute to wall off damaged myocardium in patients with dilated left ventricles and ischemic heart failure. Clinical trials are under way to test the efficacy of percutaneous ventricular restoration using the parachute device. This review describes our encounter with the parachute device, its explantation due to refractory heart failure, and surgical replacement with a left ventricular assist device. PMID:26234850

  14. Left Ventricular Assist Device Implantation After Intracardiac Parachute Device Removal.

    PubMed

    Abu Saleh, Walid K; Al Jabbari, Odeaa; Bruckner, Brian A; Suarez, Erik E; Estep, Jerry D; Loebe, Matthias

    2015-08-01

    Left ventricular assist device implantation is a proven and efficient modality for the treatment of end-stage heart failure. Left ventricular assist device versatility as a bridge to heart transplantation or destination therapy has led to improved patient outcomes with a concomitant rise in its overall use. Other less invasive treatment modalities are being developed to improve heart function and morbidity and mortality for the heart failure population. Percutaneous ventricular restoration is a new investigational therapy that deploys an intracardiac parachute to wall off damaged myocardium in patients with dilated left ventricles and ischemic heart failure. Clinical trials are under way to test the efficacy of percutaneous ventricular restoration using the parachute device. This review describes our encounter with the parachute device, its explantation due to refractory heart failure, and surgical replacement with a left ventricular assist device.

  15. A case of premature ventricular contractions, ventricular tachycardia, and arrhythmic storm induced by right ventricular pacing during cardiac resynchronization therapy: Electrophysiological mechanism and catheter ablation

    PubMed Central

    Pedretti, Stefano; Vargiu, Sara; Paolucci, Marco; Lunati, Maurizio

    2015-01-01

    A 77-year-old man with ischemic cardiomyopathy and a cardiac resynchronization therapy-defibrillator (CRT-D) device came to our attention due to incessant ventricular tachycardia and multiple implantable cardioverter defibrillator (ICD) shocks. An electrocardiogram showed non-sustained monomorphic ventricular tachycardias (NSVTs) constantly occurring after each biventricular stimulation. During an electrophysiological study, NSVTs reproducibly recurred only after right ventricular (RV) pacing; LV pacing did not induce any NSVTs. The activation map was consistent with a localized reentry at the interventricular septum, and a double exit; at the LV exit site, a single radiofrequency energy application immediately interrupted the occurrence of the NSVTs. Current evidence supports LV pacing to be pro-arrhythmogenic in few CRT patients. This unusual case shows that RV pacing during CRT could produce frequent ventricular arrhythmias and arrhythmic storm. Catheter ablation can be considered an effective therapeutic option, especially when CRT maintenance is highly advisable. PMID:26702324

  16. [Ventricular activation sequence estimated by body surface isochrone map].

    PubMed

    Hayashi, H; Ishikawa, T; Takami, K; Kojima, H; Yabe, S; Ohsugi, S; Miyachi, K; Sotobata, I

    1985-06-01

    This study was performed to evaluate the usefulness of the body surface isochrone map (VAT map) for identifying the ventricular activation sequence, and it was correlated with the isopotential map. Subjects consisted of 42 normal healthy adults, 18 patients with artificial ventricular pacemakers, and 100 patients with ventricular premature beats (VPB). The sites of pacemaker implantations were the right ventricular endocardial apex (nine cases), right ventricular epicardial apex (five cases), right ventricular inflow tract (one case), left ventricular epicardial apex (one case), and posterior base of the left ventricle via the coronary sinus (two cases). An isopotential map was recorded by the mapper HPM-6500 (Chunichi-Denshi Co.) on the basis of an 87 unipolar lead ECG, and a VAT isochrone map was drawn by a minicomputer. The normal VAT map was classified by type according to alignment of isochrone lines, and their frequency was 57.1% for type A, 16.7% for type B, and 26.2% for type C. In the VAT map of ventricular pacing, the body surface area of initial isochrone lines represented well the sites of pacemaker stimuli. In the VAT map of VPB, the sites of origin of VPB agreed well with those as determined by the previous study using an isopotential map. The density of the isochrone lines suggested the mode of conduction via the specialized conduction system or ventricular muscle. The VAT map is a very useful diagnostic method to predict the ventricular activation sequence more directly in a single sheet of the map. PMID:2419457

  17. Nipro extra-corporeal left ventricular assist device fitting after left ventricular reconstruction with mitral valve plasty.

    PubMed

    Arakawa, Mamoru; Yamaguchi, Atsushi; Nishimura, Takashi; Itoh, Satoshi; Yuri, Koichi; Kyo, Shunei; Adachi, Hideo

    2015-12-01

    Both left ventricular assist device and left ventricular reconstruction are treatment choices for severe heart failure conditions. Our institution performed a left ventricular assist device installation following a left ventricular reconstruction procedure on a 42-year-old male patient who presented with dilated cardiomyopathy and low cardiac output syndrome. A mitral valve plasty was used to correct the acute mitral valve regurgitation and we performed a Nipro extra-corporeal left ventricular assist device installation on post-operative day 14. Due to the left ventricular reconstruction that the patient had in a previous operation, we needed to attach an apical cuff on posterior apex, insert the inflow cannula with a large curve, and shift the skin insertion site laterally to the left. We assessed the angle between the cardiac longitudinal axis and the inflow cannula using computed tomography. The patient did not complain of any subjective symptoms of heart failure. Although Nipro extra-corporeal left ventricular assist device installation after left ventricular reconstruction has several difficulties historically, we have experienced a successful case.

  18. Spectral analysis of electrograms during ventricular tachycardia in a canine model: relation with epicardial isochronal maps.

    PubMed

    Sierra, G; de Jesús Gómez, M; Le Guyader, P; Soucy, B; Savard, P; Nadeau, R

    1997-07-01

    The purpose of this study was to assess the capability of magnitude-squared coherence and bicoherence to differentiate monomorphic ventricular tachycardia (MVT) and polymorphic ventricular tachycardia (PVT) in a canine model and to relate these results to the epicardial isochronal maps on a beat-to-beat basis. Unipolar electrograms were simultaneously recorded from the surface of both ventricles with a 127-lead sock electrode array in 12 open-chest anesthetized dogs. The sampling frequency was 500 Hz. Atrioventricular block was induced by formaldehyde injection into the atrioventricular node. The left anterior descending coronary artery was occluded for 60 minutes under ventricular pacing (140 beats/min). During reperfusion, 12 MVT episodes lasting more than 42 seconds were recorded. Left stellate ganglion stimulation induced five PVT episodes lasting more than 42 seconds. Each of these recordings was divided into seven segments of 3,072 points (6.144 seconds). After visual selection, 104 segments were extracted and classified as 73 MVT and 31 PVT segments. Magnitude-squared coherence was estimated as the cross-spectrum from two epicardial signals (on the right and left ventricles, respectively), normalized with the respective autopower spectrum. Bicoherence was estimated as the bispectrum normalized with the autopower spectrum. Magnitude-squared coherence correctly identified 96% of MVT and 81% of PVT segments for a total accuracy of 91%. Bicoherence estimated with the left ventricular lead correctly identified 100% of MVT and 77% of PVT segments with an accuracy of 93%. Beat-to-beat epicardial maps of MVT displayed a cluster of sites of origin close to the reperfusion area, while the sites of origin from beats during PVT were much more dispersed over both ventricles. A strong and significant correlation was found between the number of electrodes with the earliest epicardial activation and coherence (r = .76, P < .0001) and bicoherence (r = .68, P < .0001

  19. Relationship of ventricular arrhythmias to the angiographically and scintigraphically estimated extent of ventricular damage late after myocardial infarction

    SciTech Connect

    Huikuri, H.V.; Korhonen, U.R.; Linnaluoto, M.K.; Takkunen, J.T.

    1987-03-01

    In order to study the quantitative relationship of ventricular arrhythmias to myocardial damage and ischemia, 61 patients with a previous myocardial infarction (at least 6 months previously) were studied by 24-hour ambulatory ECG monitoring, cardiac catheterization, and thallium-201 scintigraphy. Thirty-five patients (57%) had no ectopic beats or only infrequent, unifocal ones and 26 patients (43%) had complex ventricular arrhythmias. Left ventricular function was lower in the latter, but the number of diseased vessels did not differ in the two groups. The reduction of thallium activity in the infarct area was more marked in patients with complex arrhythmias. Multiple thallium defects were not more common in arrhythmia patients, however. These data support the view that complex ventricular arrhythmias are more closely related to the severity of ventricular damage than the presence of myocardial ischemia remote to the area of previous infarction.

  20. Risk factors predictive of right ventricular failure after left ventricular assist device implantation.

    PubMed

    Drakos, Stavros G; Janicki, Lindsay; Horne, Benjamin D; Kfoury, Abdallah G; Reid, Bruce B; Clayson, Stephen; Horton, Kenneth; Haddad, Francois; Li, Dean Y; Renlund, Dale G; Fisher, Patrick W

    2010-04-01

    Right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation appears to be associated with increased mortality. However, the determination of which patients are at greater risk of developing postoperative RVF remains controversial and relatively unknown. We sought to determine the preoperative risk factors for the development of RVF after LVAD implantation. The data were obtained for 175 consecutive patients who had received an LVAD. RVF was defined by the need for inhaled nitric oxide for >/=48 hours or intravenous inotropes for >14 days and/or right ventricular assist device implantation. An RVF risk score was developed from the beta coefficients of the independent variables from a multivariate logistic regression model predicting RVF. Destination therapy (DT) was identified as the indication for LVAD implantation in 42% of our patients. RVF after LVAD occurred in 44% of patients (n = 77). The mortality rates for patients with RVF were significantly greater at 30, 180, and 365 days after implantation compared to patients with no RVF. By multivariate logistic regression analysis, 3 preoperative factors were significantly associated with RVF after LVAD implantation: (1) a preoperative need for intra-aortic balloon counterpulsation, (2) increased pulmonary vascular resistance, and (3) DT. The developed RVF risk score effectively stratified the risk of RV failure and death after LVAD implantation. In conclusion, given the progressively growing need for DT, the developed RVF risk score, derived from a population with a large percentage of DT patients, might lead to improved patient selection and help stratify patients who could potentially benefit from early right ventricular assist device implantation. PMID:20346326

  1. Large Right Ventricular Clot in Pulmonary Atresia With Intact Ventricular Septum: In Defense of Biventricular Approach.

    PubMed

    Dutta, Nilanjan; Ghosh, Rajarshi; Awasthy, Neeraj; Iyer, Parvathi U; Girotra, Sumir; Iyer, Krishna S

    2016-09-01

    Thrombus formation within the right ventricle (RV) in the setting of pulmonary atresia with intact ventricular septum (PAIVS) is not a very common occurrence and can be catastrophic. We present the case of a seven-month-old child with PAIVS and RV clot who successfully underwent biventricular repair. We discuss the interesting case and the rationale for management by means of biventricular repair over single ventricle repair when feasible in such a setting.

  2. Electrophysiologic features of fetal ventricular aneurysms and diverticula

    PubMed Central

    PETERS, CARLI; WACKER-GUSSMANN, ANNETTE; STRASBURGER, JANETTE F; CUNEO, BETTINA F; GOTTEINER, NINA; GULECYUZ, MEHEMET; WAKAI, RONALD T

    2014-01-01

    Objective Congenital ventricular wall defects are very rare and include congenital ventricular aneurysms (CVAs) and diverticula (CVDs). Method We report a series of five fetuses: three with CVAs and two with CVDs referred due to fetal arrhythmia. In addition to routine fetal echocardiography, fetal magnetocardiography (fMCG) was used. The literature in CVA and CVD is reviewed. Results Incessant premature ventricular contractions (PVC), mainly bigeminy and trigeminy were found in three fetuses with CVAs and in one with CVD, who also had ventricular couplets. The other fetus with CVD, referred because of PVCs, had only sinus tachycardia. ST elevation was noted in two. Fetal movement had a variable impact on PVC’s. Postnatal evaluation demonstrated two persistent left ventricular aneurysms and one persistent right CVD; one CVD resolved at 35 weeks gestation. Two neonates had incessant PVCs. Both arrhythmias resolved spontaneously while being treated with propranolol. Conclusion FMCG is complementary to echocardiographic imaging. In fetuses with left ventricular wall defects, additional electrophysiological diagnosis can be made by fMCG, including the complexity of ventricular ectopy, arrhythmic response to fetal movement, presence of ST-T wave abnormalities, and atrial amplitude increases. Prenatal risk factor assessment using fMCG can additionally support post-natal treatment and follow-up. PMID:25284224

  3. Tricuspid atresia: analysis of coronary artery distribution and ventricular morphology.

    PubMed Central

    Deanfield, J E; Tommasini, G; Anderson, R H; Macartney, F J

    1982-01-01

    There is still disagreement concerning the precise nature of the anterior ventricular chamber in "tricuspid atresia". Some argue that it is a right ventricle, while our own previous studies have suggested it is comparable to the outlet chamber seen in classical "single ventricle". We have compared the morphology of the anterior ventricular chambers in 48 examples of tricuspid atresia (absent right atrioventricular connection), 24 hearts with double inlet to the left ventricular chamber, and 15 hearts with pulmonary atresia and intact ventricular septum. Since there is further disagreement concerning the nature of the coronary artery which delimits the posterior extent of the ventricular septum in these hearts, we analysed the position of this vessel relative to external reference points on the atrioventricular junction. No significant difference was found with respect to the morphometry of hearts with tricuspid atresia (absent right atrioventricular connection) and those with double inlet. In both groups, however, significant differences were shown between hearts with ventriculoarterial concordance and discordance. Coronary artery disposition was the same in both groups and different from that found in hearts with pulmonary atresia and intact septum. We conclude that the ventricular morphology is comparable in hearts with tricuspid atresia (absent right atrioventricular connection) and those with double inlet to a left ventricular chamber. The lesions are distinguishable by their atrioventricular connection which is nevertheless univentricular in both. Images PMID:7138712

  4. The Multiple Electrocardiographic Manifestations of Ventricular Repolarization Memory

    PubMed Central

    Chiale, Pablo A; Etcheverry, Daniel; Pastori, Julio D; Fernández, Pablo A; Garro, Hugo A; González, Mario D; Elizari, Marcelo V

    2014-01-01

    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 pseudo-primary 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. PMID:24827802

  5. Risk factors for asymptomatic ventricular dysfunction in rheumatoid arthritis patients.

    PubMed

    Garza-García, Carlos; Rocío, Sánchez-Santillán; Orea-Tejeda, Arturo; Castillo-Martínez, Lilia; Eduardo, Canseco; López-Campos, José Luis; Keirns-Davis, Candace

    2013-01-01

    Objective. The aim of the study was to describe echocardiographic abnormalities in patients with rheumatoid arthritis, concurrent systemic comorbidities, rheumatologic clinical activity, serologic markers of rheumatoid arthritis, and inflammatory activity. Methods. In an observational, cross-sectional study, rheumatoid arthritis outpatients were included (n = 105). Conventional transthoracic echocardiographic variables were compared between patients with arthritis and non-RA controls (n = 41). For rheumatoid arthritis patients, articular activity and rheumatologic and inflammatory markers were obtained. Results. Ventricular dysfunction was found in 54.3% of the population: systolic (18.1%), diastolic (32.4%), and/or right (24.8%), with lower ejection fraction (P < 0.0001). Pulmonary hypertension was found in 46.9%. Other echocardiographic findings included increased left atrial diameter (P = 0.01), aortic diameter (P = 0.01), ventricular septum (P = 0.01), left ventricular posterior wall (P = 0.013), and right ventricular (P = 0.01) and atrial diameters compared to control subjects. Rheumatoid factor and anti-CCP antibodies levels were significantly elevated in cases with ventricular dysfunction. Angina and myocardial infarction, diabetes, and dyslipidemia were the main risk factors for ventricular dysfunction. Conclusions. Ventricular dysfunction is common in rheumatoid arthritis and associated with longer disease duration and increased serologic markers of rheumatoid arthritis. Screening for cardiac abnormalities should be considered in this kind of patients.

  6. Arrhythmogenic right ventricular cardiomyopathy: contribution of different electrocardiographic techniques.

    PubMed

    Moreira, Davide; Delgado, Anne; Marmelo, Bruno; Correia, Emanuel; Gama, Pedro; Pipa, João; Nunes, Luís; Santos, Oliveira

    2014-04-01

    Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiography. This was confirmed by detection of epsilon waves on analysis of the ECG, which generally go unnoticed but in this case were the key to the diagnosis. Their presence was also shown by non-conventional ECG techniques such as modified Fontaine ECG. The course of the disease culminated in the occurrence of ventricular tachycardia, which prompted placement of an implantable cardioverter-defibrillator.

  7. Risk Factors for Asymptomatic Ventricular Dysfunction in Rheumatoid Arthritis Patients

    PubMed Central

    Garza-García, Carlos; Rocío, Sánchez-Santillán; Orea-Tejeda, Arturo; Castillo-Martínez, Lilia; Eduardo, Canseco; López-Campos, José Luis; Keirns-Davis, Candace

    2013-01-01

    Objective. The aim of the study was to describe echocardiographic abnormalities in patients with rheumatoid arthritis, concurrent systemic comorbidities, rheumatologic clinical activity, serologic markers of rheumatoid arthritis, and inflammatory activity. Methods. In an observational, cross-sectional study, rheumatoid arthritis outpatients were included (n = 105). Conventional transthoracic echocardiographic variables were compared between patients with arthritis and non-RA controls (n = 41). For rheumatoid arthritis patients, articular activity and rheumatologic and inflammatory markers were obtained. Results. Ventricular dysfunction was found in 54.3% of the population: systolic (18.1%), diastolic (32.4%), and/or right (24.8%), with lower ejection fraction (P < 0.0001). Pulmonary hypertension was found in 46.9%. Other echocardiographic findings included increased left atrial diameter (P = 0.01), aortic diameter (P = 0.01), ventricular septum (P = 0.01), left ventricular posterior wall (P = 0.013), and right ventricular (P = 0.01) and atrial diameters compared to control subjects. Rheumatoid factor and anti-CCP antibodies levels were significantly elevated in cases with ventricular dysfunction. Angina and myocardial infarction, diabetes, and dyslipidemia were the main risk factors for ventricular dysfunction. Conclusions. Ventricular dysfunction is common in rheumatoid arthritis and associated with longer disease duration and increased serologic markers of rheumatoid arthritis. Screening for cardiac abnormalities should be considered in this kind of patients. PMID:24368945

  8. Arrhythmogenic right ventricular cardiomyopathy: contribution of different electrocardiographic techniques.

    PubMed

    Moreira, Davide; Delgado, Anne; Marmelo, Bruno; Correia, Emanuel; Gama, Pedro; Pipa, João; Nunes, Luís; Santos, Oliveira

    2014-04-01

    Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiography. This was confirmed by detection of epsilon waves on analysis of the ECG, which generally go unnoticed but in this case were the key to the diagnosis. Their presence was also shown by non-conventional ECG techniques such as modified Fontaine ECG. The course of the disease culminated in the occurrence of ventricular tachycardia, which prompted placement of an implantable cardioverter-defibrillator. PMID:24780127

  9. Effects of ventricular insertion sites on rotational motion of left ventricular segments studied by cardiac MR

    PubMed Central

    Robson, M D; Rider, O J; Pegg, T J; Dasanu, C A; Jung, B A; Clarke, K; Holloway, C J

    2013-01-01

    Objective: Obtaining new details for rotational motion of left ventricular (LV) segments using velocity encoding cardiac MR and correlating the regional motion patterns to LV insertion sites. Methods: Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Peak rotational velocities and circumferential velocity curves were obtained for 16 ventricular segments. Results: Reduced peak clockwise velocities of anteroseptal segments (i.e. Segments 2 and 8) and peak counterclockwise velocities of inferoseptal segments (i.e. Segments 3 and 9) were the most prominent findings. The observations can be attributed to the LV insertion sites into the right ventricle, limiting the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments as viewed from the apex. Relatively lower clockwise velocities of Segment 5 and counterclockwise velocities of Segment 6 were also noted, suggesting a cardiac fixation point between these two segments, which is in close proximity to the lateral LV wall. Conclusion: Apart from showing different rotational patterns of LV base, mid ventricle and apex, the study showed significant differences in the rotational velocities of individual LV segments. Correlating regional wall motion with known orientation of myocardial aggregates has also provided new insights into the mechanisms of LV rotational motions during a cardiac cycle. Advances in knowledge: LV insertion into the right ventricle limits the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments adjacent to the ventricular insertion sites. The pattern should be differentiated from wall motion abnormalities in cardiac pathology. PMID:24133098

  10. Reverse ventricular remodeling and improved ventricular compliance after heart transplantation in infants and young children.

    PubMed

    Farooqi, Kanwal M; Lopez, Leo; Pass, Robert H; Hsu, Daphne T; Lamour, Jacqueline M

    2014-08-01

    After heart transplantation (HT) in infants and young children, environmental and intrinsic factors may lead to changes in the geometry and compliance of the donor heart. Serial demographic, clinical, hemodynamic, and echocardiographic data were obtained from HT recipients younger than 4 years of age. Echocardiographic chamber measurement z-scores were compared using recipient body surface area from the time of HT to 1 week, 3 months, and last follow-up visit. Left ventricular end-diastolic volume (LVEDV) z-scores were correlated with pulmonary capillary wedge pressure (PCWP) at each time point. Heart transplantation was performed for 13 children between March 2009 and December 2012, 9 of whom (69%) were boys. The median age at HT was 8 months (range, 4-43 months), and the mean follow-up period was 13 ± 7 months. Left ventricular end-diastolic dimension z-scores decreased significantly (p = 0.03) between HT and 1 week, then increased from 1 week to 3 and 12 months. (-1.32 ± 1.7, -0.71 ± 1.8, 0.41 ± 2.1, 0.79 ± 2.3, respectively). A positive relationship (R(2) = 0.48) between the LVEDV z-score and PCPW was present at the last follow-up visit. For infants and young children, the allograft demonstrates appropriate growth by 1 year after HT. Left ventricular compliance improves over time.

  11. Polymorphic Electronic Circuits

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian

    2004-01-01

    Polymorphic electronics is a nascent technological discipline that involves, among other things, designing the same circuit to perform different analog and/or digital functions under different conditions. For example, a circuit can be designed to function as an OR gate or an AND gate, depending on the temperature (see figure). Polymorphic electronics can also be considered a subset of polytronics, which is a broader technological discipline in which optical and possibly other information- processing systems could also be designed to perform multiple functions. Polytronics is an outgrowth of evolvable hardware (EHW). The basic concepts and some specific implementations of EHW were described in a number of previous NASA Tech Briefs articles. To recapitulate: The essence of EHW is to design, construct, and test a sequence of populations of circuits that function as incrementally better solutions of a given design problem through the selective, repetitive connection and/or disconnection of capacitors, transistors, amplifiers, inverters, and/or other circuit building blocks. The evolution is guided by a search-and-optimization algorithm (in particular, a genetic algorithm) that operates in the space of possible circuits to find a circuit that exhibits an acceptably close approximation of the desired functionality. The evolved circuits can be tested by computational simulation (in which case the evolution is said to be extrinsic), tested in real hardware (in which case the evolution is said to be intrinsic), or tested in random sequences of computational simulation and real hardware (in which case the evolution is said to be mixtrinsic).

  12. Ventricular assist devices in the adult.

    PubMed

    Richards, Nancy M; Stahl, Mary A

    2007-01-01

    Ventricular assist devices (VADs) play an increasingly important role in the care of cardiovascular patients. Developed initially for support of cardiothoracic surgery patients experiencing difficulty in weaning from cardiopulmonary bypass, these devices have been used extensively as a bridge to cardiac transplantation for patients who are failing on medical management. Research has demonstrated the effectiveness of a VAD as destination therapy, providing a permanent means of support for patients with advanced heart failure who are not eligible for heart transplantation. Applications for VADs are expanding and advances in technology occurring to support these new applications. This article provides an overview of current and emerging VADs and nursing management of the VAD patient. PMID:17356352

  13. Endocarditis in left ventricular assist device

    PubMed Central

    Thyagarajan, Braghadheeswar; Kumar, Monisha Priyadarshini; Sikachi, Rutuja R; Agrawal, Abhinav

    2016-01-01

    Summary Heart failure is one of the leading causes of death in developed nations. End stage heart failure often requires cardiac transplantation for survival. The left ventricular assist device (LVAD) has been one of the biggest evolvements in heart failure management often serving as bridge to transplant or destination therapy in advanced heart failure. Like any other medical device, LVAD is associated with complications with infections being reported in many patients. Endocarditis developing secondary to the placement of LVAD is not a frequent, serious and difficult to treat condition with high morbidity and mortality. Currently, there are few retrospective studies and case reports reporting the same. In our review, we found the most common cause of endocarditis in LVAD was due to bacteria. Both bacterial and fungal endocarditis were associated with high morbidity and mortality. In this review we will be discussing the risk factors, organisms involved, diagnostic tests, management strategies, complications, and outcomes in patients who developed endocarditis secondary to LVAD placement.

  14. Integrative modeling of the cardiac ventricular myocyte

    PubMed Central

    Winslow, Raimond L.; Cortassa, Sonia; O'Rourke, Brian; Hashambhoy, Yasmin L.; Rice, John Jeremy; Greenstein, Joseph L.

    2011-01-01

    Cardiac electrophysiology is a discipline with a rich 50-year history of experimental research coupled with integrative modeling which has enabled us to achieve a quantitative understanding of the relationships between molecular function and the integrated behavior of the cardiac myocyte in health and disease. In this paper, we review the development of integrative computational models of the cardiac myocyte. We begin with a historical overview of key cardiac cell models that helped shape the field. We then narrow our focus to models of the cardiac ventricular myocyte and describe these models in the context of their subcellular functional systems including dynamic models of voltage-gated ion channels, mitochondrial energy production, ATP-dependent and electrogenic membrane transporters, intracellular Ca dynamics, mechanical contraction, and regulatory signal transduction pathways. We describe key advances and limitations of the models as well as point to new directions for future modeling research. PMID:20865780

  15. Metastatic right ventricular mass with intracavitary obliteration

    PubMed Central

    Kalvakuri, Kavitha; Banga, Sandeep; Upalakalin, Nalinee; Shaw, Crystal; Davila, Wilmer Fernando; Mungee, Sudhir

    2016-01-01

    Metastatic cardiac tumors are more common than the primary cardiac tumors. Cervical cancer metastasizing outside of the pelvis is commonly spread to the lungs, liver, bones and lymph nodes than to the heart. Right-sided metastasis to the heart is more common than to the left side. Intramural spread is more common than intracavitary growth of metastatic cardiac tumors leading to delayed clinical presentation. Intracavitary mass can be confused with intracavitary thrombus which can be seen in the setting of pulmonary embolism. Transthoracic echocardiography plays a major role in the decision making and management of pulmonary embolism, and this modality can also be used to diagnose cardiac masses. Other modalities like TEE, cardiac CT, cardiac MRI and PET-CT scan have further utility in delineating these masses. This may help to plan appropriate management of the right ventricular mass particularly in cases where the patient history and CT pulmonary angiography results favor the diagnosis of pulmonary embolism. We present the case of a 49-year-old woman with a history of supracervical hysterectomy and salpingo-oophorectomy on oral estrogen therapy who was admitted with complaints of pleuritic chest pain and respiratory insufficiency after a long flight. Initial work-up showed sub-segmental pulmonary embolus in the right posterior lower lobe pulmonary artery, and the patient was managed on intravenous heparin. Lack of appropriate response to standard therapy led to further evaluation. Multimodality imaging and biopsies revealed a large right intracavitary ventricular metastatic squamous cell tumor, with the cervix as the primary source. PMID:27406457

  16. Left Ventricular Diastolic Dysfunction in Peritoneal Dialysis

    PubMed Central

    Wu, Cho-Kai; Lee, Jen-Kuang; Wu, Yi-Fan; Tsai, Chia-Ti; Chiang, Fu-Tien; Hwang, Juey-Jen; Lin, Jiunn-Lee; Hung, Kuan-Yu; Huang, Jenq-Wen; Lin, Jou-Wei

    2015-01-01

    Abstract Left ventricular diastolic dysfunction (LVDD) is common among patients undergoing peritoneal dialysis (PD). We examined the relationship between LVDD, major adverse cardiovascular events (MACE), and mortality in PD patients. A total of 149 patients undergoing PD with preserved left ventricular systolic function were included and followed for 3.5 years. LVDD was diagnosed (according to the European Society of Cardiology guidelines) by conventional and tissue Doppler echocardiography. Serum high-sensitivity C-reactive protein (hsCRP) was measured. The location and volume of adipose tissue were assessed by computed tomography (CT) at the level of the fourth lumbar vertebra. Subjects with LVDD had higher levels of hsCRP, and more visceral and peritoneal fat than controls. The relationship between adjusted visceral adipose tissue and LVDD became nonsignificant when hsCRP and baseline demographic data were introduced into the logistic regression model (odds ratio = 1.52, P = 0.07). Subsequent hierarchical multivariate Cox regression analysis showed that LVDD was one of the most powerful determinants of MACE and mortality after adjusting for all confounding factors (hazard ratio [HR]: 1.71, 95% confidence interval [CI]: 1.43–3.51, P = 0.02 and HR: 2.25, 95% CI: 1.45–2.91, P = 0.04, respectively). Systemic inflammation (hsCRP) was also significantly associated with MACE and mortality (HR: 2.03, P = 0.03 and HR: 2.16, P = 0.04, respectively). LVDD is associated with systemic inflammation and increased visceral fat in patients undergoing PD. LVDD is also a sensitive, independent indicator of future MACE and mortality in PD patients. PMID:25997054

  17. Safety Testing of Left Ventricular Vent Valves.

    PubMed

    Gavin, Caroline; Coblentz, John; Acsell, Jeffrey R; Shackelford, Anthony G; Sistino, Joseph J

    2015-03-01

    Vent vacuum relief valves (VRVs) are used to limit the negative pressure at the ventricular vent catheter tip as well as prevent reversal of blood flow and prevention of air embolism. The purpose of this study was to evaluate the performance of three commercially available ventricular vent valves. The negative pressure at which the vent valve opened was measured at the valve inlet using high-fidelity pressure transducers. Also, the flow rate at which air entrainment occurred due to valve opening was recorded. Using a 51.5 cm column of saline, the resistance for each valve was calculated. The mean ± SD opening negative pressures were -231.3 ± 35.2 mmHg for the Quest Medical valve, -219.8 mmHg ± 17.2 for the Sorin valve, and -329.6 · 38.0 mmHg for the Terumo valve. The red Quest Medical valve opened at a lower flow (1.44 ± .03 L/min) than the dark blue Sorin valve (2.93 ± .01 L/min) and light blue LH130 Terumo valve (2.36 ± .02 L/min). The Sorin valve had the least resistance of 34.1 dyn-s/cm, followed by the Terumo LH130 valve resistance of 58.1 dyn·s/cm5, and the Quest Medical VRV-II valve with a resistance of 66.5 dyn·s/cm. We found that the valves are significantly different in the negative pressure generated. Understanding the limitations of these devices is important to reduce the occurrence of adverse events associated with venting and to select the best device for a specific clinical application.

  18. LEFT VENTRICULAR HYPERTROPHY AFTER HYPERTENSIVE PREGNANCY DISORDERS

    PubMed Central

    Scantlebury, Dawn C.; Kane, Garvan C.; Wiste, Heather J.; Bailey, Kent R.; Turner, Stephen T.; Arnett, Donna K.; Devereux, Richard B.; Mosley, Thomas H.; Hunt, Steven C.; Weder, Alan B.; Rodriguez, Beatriz; Boerwinkle, Eric; Weissgerber, Tracey L.; Garovic, Vesna D.

    2015-01-01

    Objective Cardiac changes of hypertensive pregnancy include left ventricular hypertrophy (LVH) and diastolic dysfunction. These are thought to regress postpartum. We hypothesized that women with a history of hypertensive pregnancy would have altered left ventricular (LV) geometry and function when compared to women with only normotensive pregnancies. Methods In this cohort study, we analyzed echocardiograms of 2637 women who participated in the Family Blood Pressure Program (FBPP). We compared LV mass and function in women with hypertensive pregnancy compared to those with normotensive pregnancies. Results Women were evaluated at a mean age of 56 years: 427 (16%) had at least one hypertensive pregnancy; 2210 (84%) had normotensive pregnancies. Compared to women with normotensive pregnancies, women with hypertensive pregnancy had a greater risk of LVH (OR: 1.42, 95% CI 1.01-1.99, p=0.05), after adjusting for age, race, research network of the FBPP, education, parity, BMI, hypertension and diabetes. When duration of hypertension was taken into account, this relationship was no longer significant (OR: 1.19, CI 0.08-1.78 p=0.38). Women with hypertensive pregnancies also had greater left atrial size and lower mitral E/A ratio after adjusting for demographic variables. The prevalence of systolic dysfunction was similar between the groups. Conclusions A history of hypertensive pregnancy is associated with LVH after adjusting for risk factors; this might be explained by longer duration of hypertension. This finding supports current guidelines recommending surveillance of women following a hypertensive pregnancy, and sets the stage for longitudinal echocardiographic studies to further elucidate progression of LV geometry and function after pregnancy. PMID:26243788

  19. Left and right ventricular diastolic function in hemodialysis patients.

    PubMed

    Rudhani, Ibrahim Destan; Bajraktari, Gani; Kryziu, Emrush; Zylfiu, Bejtush; Sadiku, Shemsedin; Elezi, Ymer; Rexhepaj, Nehat; Vitia, Arber; Emini, Merita; Abazi, Murat; Berbatovci-Ukimeraj, M; Kryeziu, Kaltrina; Hsanagjekaj, Venera; Korca, Hajrije; Ukimeri, Aferdita

    2010-11-01

    The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD) and the correlation of this function with the duration of HD. The study included 42 patients (22 females and 20 males) with chronic renal failure (CRF), treated with HD, and 40 healthy subjects (24 females and 16 males) with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects underwent detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the interventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E), acceleration time of E wave (AT-E), tricuspid E and A waves (E tr and A tr ) and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD.

  20. Percutaneous Ventricular Assist Devices: New Deus Ex Machina?

    PubMed Central

    Arroyo, Diego; Cook, Stéphane

    2011-01-01

    The development of ventricular assist devices has broadened the means with which one can treat acute heart failure. Percutaneous ventricular assist devices (pVAD) have risen from recent technological advances. They are smaller, easier, and faster to implant, all important qualities in the setting of acute heart failure. The present paper briefly describes the functioning and assets of the most common devices used today. It gives an overview of the current evidence and indications for left ventricular assist device use in cardiogenic shock and high-risk percutaneous coronary intervention. Finally, extracorporeal life support devices are dealt with in the setting of hemodynamic support. PMID:22091361

  1. Right ventricular outflow tract tachycardia worsened during pregnancy.

    PubMed

    Kambiré, Yibar; Konaté, Lassina; Millogo, Georges Rosario Christian; Sib, Elodie; Amoussou, Myriam; Nebié, Lucie Valérie Adélaïde; Niakara, Ali

    2015-01-01

    We report the case of a 35 years old woman without underlying heart disease who was diagnosed with a right ventricular outflow tract tachycardia worsened during pregnancy. The diagnosis of ventricular tachycardia was made early in her pregnancy course but the patient had symptoms three months earlier. Her disease course was marked by rhythmic storms during the second trimester of pregnancy that led to three hospitalizations accounting for about two weeks in total. The combination of nadolol 80 mg and flecainide tablets 150 mg improved her rhythmic storms. Radiofrequency allowed a radical cure of this ventricular tachycardia. The patient is now asymptomatic 27 months after radiofrequency treatment. PMID:26090018

  2. Hypothyroid cardiomyopathy complicated by a left ventricular laminar thrombus.

    PubMed

    Van Treeck, Benjamin J; Masoud, Amgad G

    2014-01-01

    Clinical hypothyroidism is the most common hormone deficiency in the United States and is found in 0.3% of the U.S. population. It is associated with characteristic symptoms that can be readily identified by a careful history and physical examination. Hypothyroidism affects many bodily systems; in particular the cardiovascular system is impacted via multiple mechanisms.3 Occasionally hypothyroidism leads to transient left ventricular systolic dysfunction, termed hypothyroid cardiomyopathy. A rare sequela of this condition is a left ventricular thrombus, which has been described in two case reports thus far. Here we report a third case of reversible hypothyroid cardiomyopathy complicated by a left ventricular laminar thrombus. PMID:25438369

  3. [Coronary effects of left ventricular hypertrophy associated with hypertension].

    PubMed

    Trimarco, B; de Luca, N; Ricciardelli, B; Rosiello, G; Lembo, G; Rendina, V; Raponi, M; Marchegiano, R; Volpe, M

    1990-12-01

    Left ventricular hypertrophy secondary to hypertension has been associated with a reduction of maximum coronary flow per unit mass as shown by the increase in the minimal threshold of coronary vascular resistance per gramme. This phenomenon has usually been attributed to an increase in muscle mass with absent or inadequate vascular compensation. However, chronic hypertension may induce a function reduction in coronary flow. In particular, it has been recently shown that coronary vascular resistances are influenced by a cardio-cardiac reflex involving the baroreceptor response. Left ventricular hypertrophy could alter the function of the ventricular receptors and favourise myocardial ischemia by preventing the adaptation of coronary flow to myocardial metabolic demands.

  4. Arrhythmogenic right ventricular cardiomyopathy/dysplasia: an updated imaging approach.

    PubMed

    Zimmerman, Stefan L

    2015-02-01

    Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a rare inherited cardiomyopathy characterized by fibrofatty replacement of the right ventricular myocardium and risk of sudden death from ventricular tachyarrhythmias. Cardiac magnetic resonance (MR) imaging plays an important role in the diagnostic evaluation of patients and family members suspected of having ARVC/D. This article discusses the epidemiology and pathophysiology of ARVC/D, reviews typical MR imaging findings and diagnostic criteria, and summarizes potential pitfalls in the MR imaging evaluation of patients suspected of having ARVC/D.

  5. Right Ventricular Adaptation Is Associated with the Glu298Asp Variant of the NOS3 Gene in Elite Athletes.

    PubMed

    Szelid, Zsolt; Lux, Árpád; Kolossváry, Márton; Tóth, Attila; Vágó, Hajnalka; Lendvai, Zsuzsanna; Kiss, Loretta; Maurovich-Horvat, Pál; Bagyura, Zsolt; Merkely, Béla

    2015-01-01

    Nitric oxide (NO), an important endogenous pulmonary vasodilator is synthetized by the endothelial NO synthase (NOS3). Reduced NO bioavailability and thus the Glu298Asp polymorphism of NOS3 may enhance right ventricular (RV) afterload and hypertrophic remodeling and influence athletic performance. To test this hypothesis world class level athletes (water polo players, kayakers, canoeists, rowers, swimmers, n = 126) with a VO2 maximum greater than 50ml/kg/min were compared with non-athletic volunteers (n = 155). Cardiopulmonary exercise tests and cardiac magnetic resonance imaging (cMRI) were performed to determine structural or functional changes. Genotype distribution of the NOS3 Glu298Asp polymorphism was not affected by gender or physical performance. Cardiac MRI showed increased stroke volume with eccentric hypertrophy in all athletes regardless of their genotype. However, the Asp allelic variant carriers had increased RV mass index (32±6g versus 27±6g, p<0.01) and larger RV stroke volume index (71±10ml versus 64±10ml, p<0.01) than athletes with a Glu/Glu genotype. Genotype was not significantly associated with athletic performance. In the non-athletic group no genotype related differences were detected. The association between the NOS3 Glu298Asp polymorphism and RV structure and dimension in elite athletes emphasizes the importance of NOS3 gene function and NO bioavailability in sport related cardiac adaptation. PMID:26517550

  6. Right Ventricular Adaptation Is Associated with the Glu298Asp Variant of the NOS3 Gene in Elite Athletes

    PubMed Central

    Kolossváry, Márton; Tóth, Attila; Vágó, Hajnalka; Lendvai, Zsuzsanna; Kiss, Loretta; Maurovich-Horvat, Pál; Bagyura, Zsolt; Merkely, Béla

    2015-01-01

    Nitric oxide (NO), an important endogenous pulmonary vasodilator is synthetized by the endothelial NO synthase (NOS3). Reduced NO bioavailability and thus the Glu298Asp polymorphism of NOS3 may enhance right ventricular (RV) afterload and hypertrophic remodeling and influence athletic performance. To test this hypothesis world class level athletes (water polo players, kayakers, canoeists, rowers, swimmers, n = 126) with a VO2 maximum greater than 50ml/kg/min were compared with non-athletic volunteers (n = 155). Cardiopulmonary exercise tests and cardiac magnetic resonance imaging (cMRI) were performed to determine structural or functional changes. Genotype distribution of the NOS3 Glu298Asp polymorphism was not affected by gender or physical performance. Cardiac MRI showed increased stroke volume with eccentric hypertrophy in all athletes regardless of their genotype. However, the Asp allelic variant carriers had increased RV mass index (32±6g versus 27±6g, p<0.01) and larger RV stroke volume index (71±10ml versus 64±10ml, p<0.01) than athletes with a Glu/Glu genotype. Genotype was not significantly associated with athletic performance. In the non-athletic group no genotype related differences were detected. The association between the NOS3 Glu298Asp polymorphism and RV structure and dimension in elite athletes emphasizes the importance of NOS3 gene function and NO bioavailability in sport related cardiac adaptation. PMID:26517550

  7. A Case of Cough-induced Ventricular Tachycardia in a Patient with a Left Ventricular Assist Device.

    PubMed

    Ruckdeschel, Emily Sue; Wolfel, Eugene; Nguyen, Duy Thai

    2016-03-01

    In this case, the patient's ventricular tachycardia (VT) was specifically induced by coughing, which has not previously been described. Decreasing the rotational speed of the left ventricular assist device (LVAD) and increasing preload by stopping the patient's nitrates and reducing diuretic dose allowed improved filling of the left ventricle (LV) and increased LV volumes. When coughing recurred, the effects on the LV cavity were less pronounced and thus VT was reduced. Although ventricular arrhythmias are common after LVAD placement, this is a unique case in which VT was caused by coughing, which is ordinarily not considered arrhythmogenic. PMID:26920187

  8. Polymorphic Evolutionary Games.

    PubMed

    Fishman, Michael A

    2016-06-01

    In this paper, I present an analytical framework for polymorphic evolutionary games suitable for explicitly modeling evolutionary processes in diploid populations with sexual reproduction. The principal aspect of the proposed approach is adding diploid genetics cum sexual recombination to a traditional evolutionary game, and switching from phenotypes to haplotypes as the new game׳s pure strategies. Here, the relevant pure strategy׳s payoffs derived by summing the payoffs of all the phenotypes capable of producing gametes containing that particular haplotype weighted by the pertinent probabilities. The resulting game is structurally identical to the familiar Evolutionary Games with non-linear pure strategy payoffs (Hofbauer and Sigmund, 1998. Cambridge University Press), and can be analyzed in terms of an established analytical framework for such games. And these results can be translated into the terms of genotypic, and whence, phenotypic evolutionary stability pertinent to the original game.

  9. Gene Polymorphisms in Chronic Periodontitis

    PubMed Central

    Laine, Marja L.; Loos, Bruno G.; Crielaard, W.

    2010-01-01

    We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP) susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (R)-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP. PMID:20339487

  10. How best to assess right ventricular function by echocardiography*

    PubMed Central

    DiLorenzo, Michael P.; Bhatt, Shivani M.; Mercer-Rosa, Laura

    2016-01-01

    Right ventricular function is a crucial determinant of long-term outcomes of children with heart disease. Quantification of right ventricular systolic and diastolic performance by echocardiography is of paramount importance, given the prevalence of children with heart disease, particularly those with involvement of the right heart, such as single or systemic right ventricles, tetralogy of Fallot, and pulmonary arterial hypertension. Identification of poor right ventricular performance can provide an opportunity to intervene. In this review, we will go through the different systolic and diastolic indices, as well as their application in practice. Quantification of right ventricular function is possible and should be routinely performed using a combination of different measures, taking into account each disease state. Quantification is extremely useful for individual patient follow-up. Laboratories should continue to strive to optimise reproducibility through quality improvement and quality assurance efforts in addition to investing in technology and training for new, promising techniques, such as three-dimensional echocardiography. PMID:26675593

  11. Ablation of frequent premature ventricular complex in an athlete.

    PubMed

    Grazioli, G; Fernández-Armenta, J; Prat, S; Berruezo, A; Brugada, J; Sitges, M

    2015-12-01

    Premature ventricular complex are common findings in the exam of many athletes. There is no extensive scientific evidence in the management of this situation particularly when associated with borderline contractile function of the left ventricle. In this case report, we present a 35-year-old asymptomatic healthy athlete with high incidence (over 10,000 beats in 24 h) of premature ventricular complex and left ventricular dilatation with dysfunction, which persisted after a resting period of 6 months without training. We performed radiofrequency ablation of the premature ventricular complex focus. After 1-year follow-up, he was asymptomatic without arrhythmia and the left ventricle normalized its size and function as shown by echocardiogram and cardiac magnetic resonance.

  12. Eisenmenger ventricular septal defect in a Humboldt penguin (Spheniscus humboldti).

    PubMed

    Laughlin, D S; Ialeggio, D M; Trupkiewicz, J G; Sleeper, M M

    2016-09-01

    The Eisenmenger ventricular septal defect is an uncommon type of ventricular septal defect characterised in humans by a traditionally perimembranous ventricular septal defect, anterior deviation (cranioventral deviation in small animal patients) of the muscular outlet septum causing malalignment relative to the remainder of the muscular septum, and overriding of the aortic valve. This anomaly is reported infrequently in human patients and was identified in a 45-day-old Humboldt Penguin, Spheniscus humboldti, with signs of poor growth and a cardiac murmur. This case report describes the findings in this penguin and summarises the anatomy and classification of this cardiac anomaly. To the authors' knowledge this is the first report of an Eisenmenger ventricular septal defect in a veterinary patient.

  13. Idiopathic Paroxysmal Ventricular Tachycardia in Infants and Children

    ERIC Educational Resources Information Center

    Hernandez, Antonio; And Others

    1975-01-01

    Laboratory tests including blood count serum electrolyte measures, and electroencephalograms were performed on seven children ages 1 day to 18 years with recurrent attacks of rapid heart action known as idiopathic paroxysmal ventricular tachycardia. (CL)

  14. How best to assess right ventricular function by echocardiography.

    PubMed

    DiLorenzo, Michael P; Bhatt, Shivani M; Mercer-Rosa, Laura

    2015-12-01

    Right ventricular function is a crucial determinant of long-term outcomes of children with heart disease. Quantification of right ventricular systolic and diastolic performance by echocardiography is of paramount importance, given the prevalence of children with heart disease, particularly those with involvement of the right heart, such as single or systemic right ventricles, tetralogy of Fallot, and pulmonary arterial hypertension. Identification of poor right ventricular performance can provide an opportunity to intervene. In this review, we will go through the different systolic and diastolic indices, as well as their application in practice. Quantification of right ventricular function is possible and should be routinely performed using a combination of different measures, taking into account each disease state. Quantification is extremely useful for individual patient follow-up. Laboratories should continue to strive to optimise reproducibility through quality improvement and quality assurance efforts in addition to investing in technology and training for new, promising techniques, such as three-dimensional echocardiography.

  15. Eisenmenger ventricular septal defect in a Humboldt penguin (Spheniscus humboldti).

    PubMed

    Laughlin, D S; Ialeggio, D M; Trupkiewicz, J G; Sleeper, M M

    2016-09-01

    The Eisenmenger ventricular septal defect is an uncommon type of ventricular septal defect characterised in humans by a traditionally perimembranous ventricular septal defect, anterior deviation (cranioventral deviation in small animal patients) of the muscular outlet septum causing malalignment relative to the remainder of the muscular septum, and overriding of the aortic valve. This anomaly is reported infrequently in human patients and was identified in a 45-day-old Humboldt Penguin, Spheniscus humboldti, with signs of poor growth and a cardiac murmur. This case report describes the findings in this penguin and summarises the anatomy and classification of this cardiac anomaly. To the authors' knowledge this is the first report of an Eisenmenger ventricular septal defect in a veterinary patient. PMID:27286906

  16. Left ventricular assist devices—current state and perspectives

    PubMed Central

    Herold, Ulf; Berkefeld, Anna; Krane, Markus; Lange, Rüdiger; Voss, Bernhard

    2016-01-01

    Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature. PMID:27621895

  17. Canine left ventricular mass estimation by two-dimensional echocardiography.

    PubMed

    Schiller, N B; Skiôldebrand, C G; Schiller, E J; Mavroudis, C C; Silverman, N H; Rahimtoola, S H; Lipton, M J

    1983-07-01

    This study was designed to develop a two-dimensional echocardiographic method of measuring the mass of the left ventricle. The general formula for an ellipse was used to derive an algorithm that described the shell volume of concentric truncated ellipsoids. In 10 canine left ventricular two-dimensional echocardiograms, this algorithm accurately predicted postmortem left ventricular mass (r = .98, SEE +/- 6 g) and was independent of cardiac cycle phase (systole vs diastole, r = .92). PMID:6851047

  18. Left ventricular assist devices-current state and perspectives.

    PubMed

    Prinzing, Anatol; Herold, Ulf; Berkefeld, Anna; Krane, Markus; Lange, Rüdiger; Voss, Bernhard

    2016-08-01

    Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature. PMID:27621895

  19. Left ventricular assist devices—current state and perspectives

    PubMed Central

    Herold, Ulf; Berkefeld, Anna; Krane, Markus; Lange, Rüdiger; Voss, Bernhard

    2016-01-01

    Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature.

  20. Ultrasound stylet for non-image-guided ventricular catheterization.

    PubMed

    Coulson, Nathaniel K; Chiarelli, Peter A; Su, David K; Chang, Jason J; MacConaghy, Brian; Murthy, Revathi; Toms, Peter; Robb, Terrence L; Ellenbogen, Richard G; Browd, Samuel R; Mourad, Pierre D

    2015-10-01

    OBJECT Urgent ventriculostomy placement can be a lifesaving procedure in the setting of hydrocephalus or elevated intracranial pressure. While external ventricular drain (EVD) insertion is common, there remains a high rate of suboptimal drain placement. Here, the authors seek to demonstrate the feasibility of an ultrasound-based guidance system that can be inserted into an existing EVD catheter to provide a linear ultrasound trace that guides the user toward the ventricle. METHODS The ultrasound stylet was constructed as a thin metal tube, with dimensions equivalent to standard catheter stylets, bearing a single-element, ceramic ultrasound transducer at the tip. Ultrasound backscatter signals from the porcine ventricle were processed by custom electronics to offer real-time information about ventricular location relative to the catheter. Data collected from the prototype device were compared with reference measurements obtained using standard clinical ultrasound imaging. RESULTS A study of porcine ventricular catheterization using the experimental device yielded a high rate of successful catheter placement after a single pass (10 of 12 trials), despite the small size of pig ventricles and the lack of prior instruction on porcine ventricular architecture. A characteristic double-peak signal was identified, which originated from ultrasound reflections off of the near and far ventricular walls. Ventricular dimensions, as obtained from the width between peaks, were in agreement with standard ultrasound reference measurements (p < 0.05). Furthermore, linear ultrasound backscatter data permitted in situ measurement of the stylet distance to the ventricular wall (p < 0.05), which assisted in catheter guidance. CONCLUSIONS The authors have demonstrated the ability of the prototype ultrasound stylet to guide ventricular access in the porcine brain. The alternative design of the device makes it potentially easy to integrate into the standard workflow for bedside EVD

  1. Sequential radionuclide imaging during paracorporeal left ventricular support.

    PubMed

    Sweet, S E; Sussman, H A; Ryan, T J; Bernhard, W F; Berger, R L

    1980-09-01

    A paracorporeal left ventricular to ascending aorta assist device (LVAD) was utilized in four patients with refractory cardiogenic shock following cardiac surgery. Hemodynamic stabilization was achieved in all four patients, two of whom were subsequently discharged from the hospital and continue to do well one year later. A technique is described for obtaining radionuclide ejection fractions (EFs) during temporary LVAD interruption. The EFs appeared to be predictive of eventual unassisted ventricular function and possibly of patient survival.

  2. Genetic Susceptibility to Cardiac and Digestive Clinical Forms of Chronic Chagas Disease: Involvement of the CCR5 59029 A/G Polymorphism

    PubMed Central

    de Oliveira, Amanda Priscila; Bernardo, Cássia Rubia; Camargo, Ana Vitória da Silveira; Ronchi, Luiz Sérgio; Borim, Aldenis Albaneze; Brandão de Mattos, Cinara Cássia; de Campos Júnior, Eumildo; Castiglioni, Lílian; Netinho, João Gomes; Cavasini, Carlos Eugênio; Bestetti, Reinaldo Bulgarelli; de Mattos, Luiz Carlos

    2015-01-01

    The clinical manifestations of chronic Chagas disease include the cardiac form of the disease and the digestive form. Not all the factors that act in the variable clinical course of this disease are known. This study investigated whether the CCR5Δ32 (rs333) and CCR5 59029 A/G (promoter region—rs1799987) polymorphisms of the CCR5 gene are associated with different clinical forms of chronic Chagas disease and with the severity of left ventricular systolic dysfunction in patients with chronic Chagas heart disease (CCHD). The antibodies anti-T. cruzi were identified by ELISA. PCR and PCR-RFLP were used to identify the CCR5Δ32 and CCR5 59029 A/G polymorphisms. The chi-square test was used to compare variables between groups. There was a higher frequency of the AA genotype in patients with CCHD compared with patients with the digestive form of the disease and the control group. The results also showed a high frequency of the AG genotype in patients with the digestive form of the disease compared to the other groups. The results of this study show that the CCR5Δ32 polymorphism does not seem to influence the different clinical manifestations of Chagas disease but there is involvement of the CCR5 59029 A/G polymorphism in susceptibility to the different forms of chronic Chagas disease. Besides, these polymorphisms do not influence left ventricular systolic dysfunction in patients with CCHD. PMID:26599761

  3. Genetic Susceptibility to Cardiac and Digestive Clinical Forms of Chronic Chagas Disease: Involvement of the CCR5 59029 A/G Polymorphism.

    PubMed

    de Oliveira, Amanda Priscila; Bernardo, Cássia Rubia; Camargo, Ana Vitória da Silveira; Ronchi, Luiz Sérgio; Borim, Aldenis Albaneze; de Mattos, Cinara Cássia Brandão; de Campos Júnior, Eumildo; Castiglioni, Lílian; Netinho, João Gomes; Cavasini, Carlos Eugênio; Bestetti, Reinaldo Bulgarelli; de Mattos, Luiz Carlos

    2015-01-01

    The clinical manifestations of chronic Chagas disease include the cardiac form of the disease and the digestive form. Not all the factors that act in the variable clinical course of this disease are known. This study investigated whether the CCR5Δ32 (rs333) and CCR5 59029 A/G (promoter region--rs1799987) polymorphisms of the CCR5 gene are associated with different clinical forms of chronic Chagas disease and with the severity of left ventricular systolic dysfunction in patients with chronic Chagas heart disease (CCHD). The antibodies anti-T. cruzi were identified by ELISA. PCR and PCR-RFLP were used to identify the CCR5Δ32 and CCR5 59029 A/G polymorphisms. The chi-square test was used to compare variables between groups. There was a higher frequency of the AA genotype in patients with CCHD compared with patients with the digestive form of the disease and the control group. The results also showed a high frequency of the AG genotype in patients with the digestive form of the disease compared to the other groups. The results of this study show that the CCR5Δ32 polymorphism does not seem to influence the different clinical manifestations of Chagas disease but there is involvement of the CCR5 59029 A/G polymorphism in susceptibility to the different forms of chronic Chagas disease. Besides, these polymorphisms do not influence left ventricular systolic dysfunction in patients with CCHD.

  4. Ventricular repolarization in a rat model of global heart failure.

    PubMed

    Krandycheva, Valeria; Kharin, Sergey; Strelkova, Marina; Shumikhin, Konstantin; Sobolev, Aleksey; Shmakov, Dmitry

    2013-07-01

    Isoproterenol in high doses induces infarction-like myocardial damage and structural and functional remodelling of the ventricular myocardium. The purpose of the present study was to investigate ventricular repolarization in a rat model of isoproterenol-induced heart failure. Isoproterenol was administered twice to female Wistar rats (170 mg/kg, s.c., 24 h apart). Four weeks after the injections, cardiac output was measured and unipolar epicardial ventricular electrograms were recorded in situ. Activation-recovery intervals were calculated to assess repolarization. Histological examination of the heart ventricles was also performed. Heart failure in rats treated with isoproterenol was indicated by myocardial histopathological damage and reduced cardiac output. In rats with heart failure, the regional differences in activation-recovery interval prolongation over the ventricular epicardium resulted in increasing heterogeneity in the activation-recovery interval distribution and increasing repolarization heterogeneity of the ventricular subepicardium. Myocardial damage and haemodynamic changes in heart failure induced by isoproterenol were accompanied by significant changes in ventricular repolarization, which were not associated with myocardial hypertrophy.

  5. Fetal Right Ventricular Diverticulum Detected by Prenatal Ultrasound Screening

    PubMed Central

    Hayashi, Kaori; Tsuji, Shunichiro; Ono, Tetsuo; Ishiko, Akiko; Takahashi, Kentaro; Murakami, Takashi

    2016-01-01

    Prenatal ultrasound screening has allowed for the detection of in utero cardiac abnormalities. Specifically, distinction is possible between ventricular diverticula and aneurysms, which is important because each condition has a different clinical outcome. We report the case of a 35-year-old, gravida 1, para 1 woman, with no significant past medical history, who underwent routine prenatal ultrasound screening at 32 weeks' gestation. A four-chamber ultrasound of the fetal heart combined with M-mode echocardiography showed abnormal dilatation of the right ventricular chamber measuring 2.2 cm × 1.0 cm but with normal contractility. Delivery was performed at full term by cesarean section, and a right ventricular diverticulum was confirmed by postnatal cardiac computed tomography. The baby developed normally with no cardiac sequelae during followup. This case demonstrates the importance of making a correct diagnosis of ventricular diverticula by prenatal ultrasound when abnormal dilatation of the fetal ventricle is identified during routine screening. Because evaluating the wall contractility by M-mode ultrasound leads to evaluating whether it has the myocardium, we conclude that M-mode echocardiography is effective for the purpose of prenatal cardiac diagnosis and can distinguish between ventricular aneurysms and functioning ventricular diverticula.

  6. Unruptured Sinus of Valsalva Aneurysm with Right Ventricular Outflow Tract Obstruction and Supracristal Ventricular Septal Defect: A Rare Case.

    PubMed

    Sridhar, Ganiga Srinivasaiah; Sadiq, Muhammad Athar; Ahmad, Wan Azman Wan; Supuramaniam, Chitra; Watson, Timothy; Abidin, Imran Zainal; Chee, Kok Han

    2015-10-01

    Unruptured right sinus of Valsalva aneurysm that causes severe obstruction of the right ventricular outflow tract is extremely rare. We describe the case of a 47-year-old woman who presented with exertional dyspnea. Upon investigation, we discovered an unruptured right sinus of Valsalva aneurysm with associated right ventricular outflow tract obstruction and a supracristal ventricular septal defect. To our knowledge, only 2 such cases have previously been reported in the medical literature. Although treatment of unruptured sinus of Valsalva aneurysm remains debatable, surgery should be considered for extremely large aneurysms or for progressive enlargement of the aneurysm on serial evaluation. Surgery was undertaken in our patient because there was clear evidence of right ventricular outflow tract obstruction, right-sided heart dilation, and associated exertional dyspnea.

  7. Use of right ventricular support with a centrifugal pump in post-valve surgery right ventricular failure: a case series.

    PubMed

    Moulodi, Abdol Rasoul; Sheibat Zadeh, Gholam Reza; Sabzi, Feridoun

    2014-01-12

    The optimal treatment method for right ventricular failure after valve surgery complicated by a low cardiac output has not been determined, although several case reports have been published on patients with ventricular failure and arrhythmia who were bridged to cardiac transplantation using biventricular or left ventricular assist devices. This case series illustrates successful circulatory support of 4 patients with prolonged low cardiac outputs and right ventricular failure and arrhythmias after valvular heart surgery with or without severe pulmonary hypertension. In-hospital death occurred in one patient and 3 patients were discharged from the hospital with good general condition. At two years' follow-up, 2 patients were in functional class one but another patient underwent laparotomy for multiple splenic abscesses and died from multiple organ failure.

  8. Left ventricular mechanics and arterial-ventricular coupling following high-intensity interval exercise.

    PubMed

    Cote, Anita T; Bredin, Shannon S D; Phillips, Aaron A; Koehle, Michael S; Glier, Melissa B; Devlin, Angela M; Warburton, Darren E R

    2013-12-01

    High-intensity exercise induces marked physiological stress affecting the secretion of catecholamines. Sustained elevations in catecholamines are thought to desensitize cardiac beta receptors and may be a possible mechanism in impaired cardiac function following strenuous exercise. In addition, attenuated arterial-ventricular coupling may identify vascular mechanisms in connection with postexercise attenuations in ventricular function. Thirty-nine normally active (NA) and endurance-trained (ET) men and women completed an echocardiographic evaluation of left ventricular function before and after an acute bout of high-intensity interval exercise (15 bouts of 1:2 min work:recovery cycling: 100% peak power output and 50 W, respectively). Following exercise, time to peak twist and peak untwisting velocity were delayed (P < 0.01) but did not differ by sex or training status. Interactions for sex and condition (rest vs. exercise) were found for longitudinal diastolic strain rate (men, 1.46 ± 0.19 to 1.28 ± 0.23 s(-1) vs. women, 1.62 ± 0.25 to 1.63 ± 0.26 s(-1); P = 0.01) and arterial elastance (men 2.20 ± 0.65 to 3.24 ± 1.02 mmHg · ml(-1) · m(-2) vs. women 2.51 ± 0.61 to 2.93 ± 0.68 mmHg · ml(-1) · m(-2); P = 0.04). No cardiac variables were found associated with catecholamine levels. The change in twist mechanics was associated with baseline aortic pulse-wave velocity (r(2) = 0.27, P = 0.001). We conclude that males display greater reductions in contractility in response to high-intensity interval exercise, independent of catecholamine concentrations. Furthermore, a novel association of arterial stiffness and twist mechanics following high-intensity acute exercise illustrates the influence of vascular integrity on cardiac mechanics.

  9. Angiotensin converting enzyme gene polymorphism in familial hypertrophic cardiomyopathy patients

    SciTech Connect

    Yu, B; Peric, S.; Ross, D.

    1994-09-01

    An insertion/deletion (I/D) polymorphism of the angiotensin I converting enzyme (ACE) gene is a useful predictor of human plasma ACE levels. ACE levels tend to be lowest in subjects with ACE genotype DD and intermediate in subjects with ACE genotype ID. Angiotensin II (Ang II) as a product of ACE is a cardiac growth factor and produces a marked hypertrophy of the chick myocyte in cell culture. Rat experiments also suggest that a small dose of ACE inhibitor that does not affect the afterload results in prevention or regression of cardiac hypertrophy. In order to study the relationship of ACE and the severity of hypertrophy, the ACE genotype has been determined in 28 patients with a clinical diagnosis of familial hypertrophic cardiomyopathy (FHC) and 51 normal subjects. The respective frequencies of I and D alleles were: 0.52 and 0.48 (in FHC patients) and 0.44 and 0.56 (in the normal controls). There was no significant difference in the allele frequencies between FHC and normal subjects ({chi}{sup 2}=0.023, p>0.05). The II, ID, and DD genotypes were present in 7, 15, and 6 FHC patients, respectively. The averages of maximal thickness of the interventricular septum measured by echocardiography or at autopsy were 18 {plus_minus}3, 19{plus_minus}4, and 19{plus_minus}3 mm in II, ID and DD genotypes, respectively. The ACE gene polymorphism did not correlate with the severity of left ventricular hypertrophy in FHC patients (r{sub s}=0.231, p>0.05). These results do not necessarily exclude the possible effect of Ang II on the hypertrophy since the latter may be produced through the action of chymase in the human ventricles. However, ACE gene polymorphism is not a useful predictor of the severity of myocardial hypertrophy in FHC patients.

  10. [The process of ventricular remodeling after acute myocardial infarct associated with left ventricular aneurysm and ventricular septum rupture treated with radical surgery].

    PubMed

    Hůla, J

    1997-01-01

    Even after a successful operation of mechanical complications on account of acute myocardial infarction gradually developing adverse remodelling of the left ventricle has to be envisaged. In a six-year clinical study by means of echocardiography the authors followed up systematically some cardiac dimensions and volumes and functional systolic and diastolic left ventricular parameters. The changes pertained in particular to the endsystolic and enddiastolic volume, the ejection fraction, the peak maximum rate, early and late diastolic filling and their ratio as well as to indirect values of the mean pressure in the pulmonary artery. These changes, which at first indicated impaired relaxation, are caused subsequently by increasing stiffness of the left ventricle. With regard to the large number of complicated pathophysiological phenomena pertaining to active relaxation and passive elastic properties of the left ventricle during ventricular diastole, different Doppler parameters must be evaluated very carefully, individually and with regard to the clinical condition. Attention is drawn to the importance of complicating mitral regurgitations and an increased pressure in the left atrium and lesser circulation after aneurysmectomy of the left ventricle. Mitral regurgitation has an impact on the process of left ventricular filling investigated by means of diastolic Doppler functions. Despite limitations of echocardiographic methods within the framework of assessment of diastolic left ventricular functions after myocardial infarction echocardiography remains the main means for evaluating left ventricular function by a non-invasive route and its position in this respect is irreplaceable. Further experimental work is needed for better understanding, use and more intelligent interpretation of non-invasive parameters of left ventricular function also in these complicated conditions after surgery of mechanical complications resulting from myocardial infarction. PMID:9221569

  11. Preferential Nucleation during Polymorphic Transformations

    PubMed Central

    Sharma, H.; Sietsma, J.; Offerman, S. E.

    2016-01-01

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR’s) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR’s with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller – and therefore nucleation more probable - with increasing number of special OR’s. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material. PMID:27484579

  12. Preferential Nucleation during Polymorphic Transformations

    NASA Astrophysics Data System (ADS)

    Sharma, H.; Sietsma, J.; Offerman, S. E.

    2016-08-01

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR’s) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR’s with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller – and therefore nucleation more probable - with increasing number of special OR’s. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material.

  13. Preferential Nucleation during Polymorphic Transformations.

    PubMed

    Sharma, H; Sietsma, J; Offerman, S E

    2016-08-03

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR's) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR's with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller - and therefore nucleation more probable - with increasing number of special OR's. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material.

  14. Preferential Nucleation during Polymorphic Transformations.

    PubMed

    Sharma, H; Sietsma, J; Offerman, S E

    2016-01-01

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR's) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR's with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller - and therefore nucleation more probable - with increasing number of special OR's. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material. PMID:27484579

  15. Ventricular volume measured from sestamibi gated tomograms

    SciTech Connect

    Nichols, K.; DePuey, E.G.; Salensky, H. |

    1994-05-01

    Since left ventricular (LV) end-diastolic volume (EDV) and end-systolic volume (ESV) are valuable prognostic indicators, deriving accurate LV volumes could enhance the prognostic utility of Tc-99m sestamibi myocardial perfusion SPECT. We examined two methods of obtaining volumes adjunctive to sestamibi injections. A previously reported method of computing volumes from gated first pass (FP) images by combining maximum and total counts with IV maximum depth information from an orthogonal view was tested by imaging the LV chamber of a thoracic/cardiac phantom in RAO-30{degrees} and LAO-60{degrees} projections. Computed volume agreed with known volume to within 4.9%. In a separate experiment, tomograms of the simulated myocardium of the phantom were acquired which were reoriented into vertical and horizontal long-axis slices on which an observer drew inner LV outlines, and from which volume was computed using a scatter-corrected Simpson`s rule method. Computed phantom volume agreed with known simulated LV volume to within 3.5%. To evaluate these volume methods for patient data, we analyzed LV ED and ES images of 39 patients acquired in simultaneous biplane RAO-30{degrees} and LAO-60{degrees} projections during FP bolus transit of 840 MBq Tc-99m sestamibi. One hour later, 64 projections were acquired in 64{sup 2} matrices for 20 seconds each, gated at 8 frames per R-R interval.

  16. CFD Modeling of Ventricular Assist Device

    NASA Astrophysics Data System (ADS)

    Wood, Houston; Allaire, Paul; McDaniel, James; Landrot, Nicolas; Day, Steven

    2000-11-01

    The HeartQuest blood pump is a centrifugal pump in which the rotor is suspended by magnetic bearings. The pump is being designed for use as an implantable Ventricular Assist Device. In previous computational modeling of the pump, the blood flow in three separate regions has been analyzed: the impeller, the front clearance region and the back clearance region. In this approach, the models are axially symmetric, and the calculations are simplified. However, the real flow is 3-dimensional because of the exit volute. In order to validate computational fluid dynamics modeling of the blood pump, a complete computational model has been realized. The computational model includes an impeller, a front clearance gap, a back clearance gap, and an exit volute. The full Navier-Stokes equations are solved inside the pump, and a k-e model is used to model the turbulence. The software used is the commercially available program TASCFLOW from the company AEA. In this paper, numerical predictions will be explained and compared with experimental measurements of the flow field obtained by laser particle imaging velocimetry.

  17. Endocarditis in left ventricular assist device

    PubMed Central

    Thyagarajan, Braghadheeswar; Kumar, Monisha Priyadarshini; Sikachi, Rutuja R; Agrawal, Abhinav

    2016-01-01

    Summary Heart failure is one of the leading causes of death in developed nations. End stage heart failure often requires cardiac transplantation for survival. The left ventricular assist device (LVAD) has been one of the biggest evolvements in heart failure management often serving as bridge to transplant or destination therapy in advanced heart failure. Like any other medical device, LVAD is associated with complications with infections being reported in many patients. Endocarditis developing secondary to the placement of LVAD is not a frequent, serious and difficult to treat condition with high morbidity and mortality. Currently, there are few retrospective studies and case reports reporting the same. In our review, we found the most common cause of endocarditis in LVAD was due to bacteria. Both bacterial and fungal endocarditis were associated with high morbidity and mortality. In this review we will be discussing the risk factors, organisms involved, diagnostic tests, management strategies, complications, and outcomes in patients who developed endocarditis secondary to LVAD placement. PMID:27672540

  18. Ventricular fibrillation time constant for swine.

    PubMed

    Wu, Jiun-Yan; Nimunkar, Amit J; Sun, Hongyu; O'Rourke, Ann; Huebner, Shane; Will, James A; Webster, John G

    2008-10-01

    The strength-duration curve for cardiac excitation can be modeled by a parallel resistor-capacitor circuit that has a time constant. Experiments on six pigs were performed by delivering current from the X26 Taser dart at a distance from the heart to cause ventricular fibrillation (VF). The X26 Taser is an electromuscular incapacitation device (EMD), which generates about 50 kV and delivers a pulse train of about 15-19 pulses s(-1) with a pulse duration of about 150 micros and peak current about 2 A. Similarly a continuous 60 Hz alternating current of the amplitude required to cause VF was delivered from the same distance. The average current and duration of the current pulse were estimated in both sets of experiments. The strength-duration equation was solved to yield an average time constant of 2.87 ms +/- 1.90 (SD). Results obtained may help in the development of safety standards for future electromuscular incapacitation devices (EMDs) without requiring additional animal tests.

  19. Arrhythmogenic Right Ventricular Dysplasia in Neuromuscular Disorders

    PubMed Central

    Finsterer, Josef; Stöllberger, Claudia

    2016-01-01

    OBJECTIVES Arrhythmogenic right ventricular dysplasia (ARVD) is a rare, genetic disorder predominantly affecting the right ventricle. There is increasing evidence that in some cases, ARVD is due to mutations in genes, which have also been implicated in primary myopathies. This review gives an overview about myopathy-associated ARVD and how these patients can be managed. METHODS A literature review was done using appropriate search terms. RESULTS The myopathy, which is most frequently associated with ARVD, is the myofibrillar myopathy due to desmin mutations. Only in a single patient, ARVD was described in myotonic dystrophy type 1. However, there are a number of genes causing either myopathy or ARVD. These genes include lamin A/C, ZASP/cypher, transmembrane protein-43, titin, and the ryanodine receptor-2 gene. Diagnosis and treatment are identical for myopathy-associated ARVD and nonmyopathy-associated ARVD. CONCLUSIONS Patients with primary myopathy due to mutations in the desmin, dystrophia myotonica protein kinase, lamin A/C, ZASP/cypher, transmembrane protein-43, titin, or the ryanodine receptor-2 gene should be screened for ARVD. Patients carrying a pathogenic variant in any of these genes should undergo annual cardiological investigations for cardiac function and arrhythmias. PMID:27790050

  20. [Takotsubo syndrome. Transient left ventricular dyskinesia].

    PubMed

    Pérez Pérez, F M; Sánchez Salado, J

    2014-03-01

    The Takotsubo syndrome, also called transient apical dyskinesia syndrome, was first described in Japan in the 1990s. It is a rare entity found in almost 1% of all patients with suspicion of acute coronary syndrome. It usually affects postmenopausal women with a few cardiovascular risk factors. It is characterized by angina-type chest pain, electrocardiographic changes, elevation of the enzymes of myocardial injury, absence of coronary obstruction on angiography, and a characteristic left ventricular anteroapical dyskinesia, which returns to normal within a few days. Severe emotional stress is the most common trigger for this syndrome. The aetiopathogenesis of this syndrome remains to be defined. This syndrome has been considered a clinical condition since 2001, when a series of 88 cases was published. It is a disease with a partially known mechanism, characterised by the morphology adopted by the left ventricle secondary to hypokinesis or dyskinesia of the apical segments, and hypercontractility of basal segments. Unlike acute coronary syndrome, patients with left ventricle dysfunction do not have atherothrombotic disease in the coronary arteries. In addition, the alterations described are reversible. Some clinical diagnostic criteria have been proposed, although they are still controversial, as well as in the complementary examinations required for diagnosis.

  1. Loperamide Induced Life Threatening Ventricular Arrhythmia

    PubMed Central

    Bodar, Vijaykumar; Singh, Sharanjit; Frumkin, William; Mangla, Aditya; Doshi, Kaushik

    2016-01-01

    Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient's QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community. PMID:27547470

  2. Loperamide Induced Life Threatening Ventricular Arrhythmia.

    PubMed

    Upadhyay, Ankit; Bodar, Vijaykumar; Malekzadegan, Mohammad; Singh, Sharanjit; Frumkin, William; Mangla, Aditya; Doshi, Kaushik

    2016-01-01

    Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient's QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community. PMID:27547470

  3. Endocarditis in left ventricular assist device.

    PubMed

    Thyagarajan, Braghadheeswar; Kumar, Monisha Priyadarshini; Sikachi, Rutuja R; Agrawal, Abhinav

    2016-08-01

    Heart failure is one of the leading causes of death in developed nations. End stage heart failure often requires cardiac transplantation for survival. The left ventricular assist device (LVAD) has been one of the biggest evolvements in heart failure management often serving as bridge to transplant or destination therapy in advanced heart failure. Like any other medical device, LVAD is associated with complications with infections being reported in many patients. Endocarditis developing secondary to the placement of LVAD is not a frequent, serious and difficult to treat condition with high morbidity and mortality. Currently, there are few retrospective studies and case reports reporting the same. In our review, we found the most common cause of endocarditis in LVAD was due to bacteria. Both bacterial and fungal endocarditis were associated with high morbidity and mortality. In this review we will be discussing the risk factors, organisms involved, diagnostic tests, management strategies, complications, and outcomes in patients who developed endocarditis secondary to LVAD placement. PMID:27672540

  4. Genetic polymorphisms and disease prevention.

    PubMed

    Mahoney, Martin C

    2007-06-15

    Building upon the resources of traditional epidemiology, molecular epidemiology has extended our understanding that disease risk varies based not only upon acquired factors (e.g., exposures, behaviors, demographics), but also as a function of inherited factors (e.g., genetic polymorphisms). Individual susceptibility to cancer is influenced by polymorphisms in phase I enzymes (e.g., activation), phase 2 enzymes (e.g., detoxification), defects in the repair of DNA damage and other cancer susceptibility genes. Because tobacco use and nutrition represent behaviors/exposures which account for a significant number of cancer cases and deaths, these two factors are used to illustrate the relationship between genetic polymorphisms and disease prevention. Susceptibility to the health risks of smoking appears to be influenced by genetic factors that impact initiation, dependence, and nicotine metabolism. Nutrient metabolism also involves polymorphic enzyme pathways and gene-nutrient interactions may influence cancer risk. While the discipline of molecular epidemiology continues to face methodologic challenges related to the need to study large numbers of subjects, current knowledge can be applied to prevention activities. Genetic polymorphisms, and other molecular markers, can be used to develop clinical prevention studies targeted to unique subsets of persons at the highest risk of developing disease. Knowledge about the relationships between polymorphisms and disease outcomes can also be used for reinforcing healthy lifestyles, motivating positive behavior changes, helping to target medical therapy, and aiding in better focusing surveillance activities. PMID:17252563

  5. Morphology of left ventricular outflow tract structures in patients with subaortic stenosis and a ventricular septal defect.

    PubMed Central

    Kitchiner, D; Jackson, M; Malaiya, N; Walsh, K; Peart, I; Arnold, R; Smith, A

    1994-01-01

    OBJECTIVE--To compare the incidence and prognosis of subaortic stenosis associated with a ventricular septal defect and to define the morphological basis of subaortic stenosis. DESIGN--Presentation and follow up data on 202 patients with subaortic stenosis seen at the Royal Liverpool Children's Hospital between 1 January 1960 and 31 December 1991 were reviewed. Survivors were traced to assess their current clinical state. Necropsy specimens of 291 patients with lesions associated with subaortic stenosis were also examined. RESULTS--In the clinical study; 65 (32.1%) of the 202 patients with subaortic stenosis had a ventricular septal defect (excluding an atrioventricular septal defect). 32 of these patients had a short segment (fibromuscular) subaortic stenosis. 33 had subaortic stenosis produced by deviation of muscular components of the outflow tracts. In 17 patients (51.5%) this was caused by posterior deviation or extension of structures into the left ventricular outflow tract, resulting in obstruction above the ventricular septal defect. In the other 16 patients (48.5%) there was over-riding of the aorta with concordant ventriculoarterial connections, (without compromise to right ventricular outflow) producing subaortic stenosis below the ventricular septal defect. Additional fibrous obstruction occurred in 39% of the patients with deviated structures. The age at presentation was lower (P < 0.01) in patients with deviated structures (median (range) 0.4 (0 to 9.2) months) than in those with short segment obstruction (median (range) 4.2 (0 to 84.9) months). The incidence of aortic arch obstruction was higher (P < 0.002) in patients with deviated structures than in those with short segment obstruction (38%). In the morphological study 35 pathological specimens showed obstructive muscular structures in the left ventricular outflow tract either above or below the ventricular septal defect. 16 had either posterior deviation of the outlet septum or extension of the

  6. New polymorphous computing fabric.

    SciTech Connect

    Wolinski, C.; Gokhale, M.; McCabe, K. P.

    2002-01-01

    This paper introduces a new polymorphous computing Fabric well suited to DSP and Image Processing and describes its implementation on a Configurable System on a Chip (CSOC). The architecture is highly parameterized and enables customization of the synthesized Fabric to achieve high performance for a specific class of application. For this reason it can be considered to be a generic model for hardware accelerator synthesis from a high level specification. Another important innovation is the Fabric uses a global memory concept, which gives the host processor random access to all the variables and instructions on the Fabric. The Fabric supports different computing models including MIMD, SPMD and systolic flow and permits dynamic reconfiguration. We present a specific implementation of a bank of FIR filters on a Fabric composed of 52 cells on the Altera Excalibur ARM running at 33 MHz. The theoretical performance of this Fabric is 1.8 GMACh. For the FIR application we obtain 1.6 GMAC/s real performance. Some automatic tools have been developed like the tool to provide a host access utility and assembler.

  7. Dysplastic conditions of the right ventricular myocardium: Uhl's anomaly vs arrhythmogenic right ventricular dysplasia.

    PubMed Central

    Gerlis, L M; Schmidt-Ott, S C; Ho, S Y; Anderson, R H

    1993-01-01

    OBJECTIVE--Since 1905 there have been many reports of cases in which the right ventricle was deficient in myocardium. Several terms have been used to describe this condition. Of these, "Uhl's anomaly" and "arrhythmogenic right ventricular dysplasia" are most often used. Our study investigates the relation between these entities. METHOD--Five cases with a primary deficiency of the right ventricular musculature were examined. The findings were compared with those published reports to evaluate the similarities and differences between Uhl's anomaly and arrhythmogenic dysplasia. RESULTS--The five cases showed two patterns of myocardial deficiency in the right ventricle. On the one hand, the parietal wall was paper thin with complete absence of musculature and apposition of the endocardial and epicardial layers. On the other hand, patchy, localised fibrofatty tissue replacement was found within the parietal musculature. Evidence from our cases, combined with analysis of other publications, showed different modes and timing of clinical presentation of the patients with these two anatomical conditions, congestive heart failure or arrhythmia. CONCLUSIONS--The conditions variously described as Uhl's anomaly and arrhythmogenic dysplasia are separate and distinct morphological entities. Images PMID:8435240

  8. Inhaled Nitric Oxide Augments Left Ventricular Assist Device Capacity by Ameliorating Secondary Right Ventricular Failure.

    PubMed

    Lovich, Mark A; Pezone, Matthew J; Wakim, Matthew G; Denton, Ryan J; Maslov, Mikhail Y; Murray, Michael R; Tsukada, Hisashi; Agnihotri, Arvind K; Roscigno, Robert F; Gamero, Lucas G; Gilbert, Richard J

    2015-01-01

    Clinical right ventricular (RV) impairment can occur with left ventricular assist device (LVAD) use, thereby compromising the therapeutic effectiveness. The underlying mechanism of this RV failure may be related to induced abnormalities of septal wall motion, RV distension and ischemia, decreased LV filling, and aberrations of LVAD flow. Inhaled nitric oxide (NO), a potent pulmonary vasodilator, may reduce RV afterload, and thereby increase LV filling, LVAD flow, and cardiac output (CO). To investigate the mechanisms associated with LVAD-induced RV dysfunction and its treatment, we created a swine model of hypoxia-induced pulmonary hypertension and acute LVAD-induced RV failure and assessed the physiological effects of NO. Increased LVAD speed resulted in linear increases in LVAD flow until pulse pressure narrowed. Higher speeds induced flow instability, LV collapse, a precipitous fall of both LVAD flow and CO. Nitric oxide (20 ppm) treatment significantly increased the maximal achievable LVAD speed, LVAD flow, CO, and LV diameter. Nitric oxide resulted in decreased pulmonary vascular resistance and RV distension, increased RV ejection, promoted LV filling and improved LVAD performance. Inhaled NO may thus have broad utility for the management of biventricular disease managed by LVAD implantation through the effects of NO on LV and RV wall dynamics. PMID:25710771

  9. A Physiological Controller for Turbodynamic Ventricular Assist Devices Based on Left Ventricular Systolic Pressure.

    PubMed

    Petrou, Anastasios; Ochsner, Gregor; Amacher, Raffael; Pergantis, Panagiotis; Rebholz, Mathias; Meboldt, Mirko; Schmid Daners, Marianne

    2016-09-01

    The current article presents a novel physiological feedback controller for turbodynamic ventricular assist devices (tVADs). This controller is based on the recording of the left ventricular (LV) pressure measured at the inlet cannula of a tVAD thus requiring only one pressure sensor. The LV systolic pressure (SP) is proposed as an indicator to determine the varying perfusion requirements. The algorithm to extract the SP from the pump inlet pressure signal used for the controller to adjust the speed of the tVAD shows robust behavior. Its performance was evaluated on a hybrid mock circulation. The experiments with changing perfusion requirements were compared with a physiological circulation and a pathological one assisted with a tVAD operated at constant speed. A sensitivity analysis of the controller parameters was conducted to identify their limits and their influence on a circulation. The performance of the proposed SP controller was evaluated for various values of LV contractility, as well as for a simulated pressure sensor drift. The response of a pathological circulation assisted by a tVAD controlled by the introduced SP controller matched the physiological circulation well, while over- and underpumping events were eliminated. The controller presented a robust performance during experiments with simulated pressure sensor drift. PMID:27645395

  10. Effect of Continued Cardiac Resynchronization Therapy on Ventricular Arrhythmias After Left Ventricular Assist Device Implantation.

    PubMed

    Schleifer, John William; Mookadam, Farouk; Kransdorf, Evan P; Nanda, Udai; Adams, Jonathon C; Cha, Stephen; Pajaro, Octavio E; Steidley, David Eric; Scott, Robert L; Carvajal, Tomas; Saadiq, Rayya A; Srivathsan, Komandoor

    2016-08-15

    Cardiac resynchronization therapy (CRT) reduces ventricular arrhythmia (VA) burden in some patients with heart failure, but its effect after left ventricular assist device (LVAD) implantation is unknown. We compared VA burden in patients with CRT devices in situ who underwent LVAD implantation and continued CRT (n = 39) to those who had CRT turned off before discharge (n = 26). Implantable cardioverter-defibrillator (ICD) shocks were significantly reduced in patients with continued CRT (1.5 ± 2.7 shocks per patient vs 5.5 ± 9.3 with CRT off, p = 0.014). There was a nonsignificant reduction in cumulative VA episodes per patient with CRT continued at discharge (42 ± 105 VA per patient vs 82 ± 198 with CRT off, p = 0.29). On-treatment analysis by whether CRT was on or off identified a significantly lower burden of VA (17 ± 1 per patient-year CRT on vs 37 ± 1 per patient-year CRT off, p <0.0001) and ICD shocks (1.2 ± 0.3 per patient-year CRT on vs 1.7 ± 0.3 per patient-year CRT off, p = 0.018). In conclusion, continued CRT is associated with significantly reduced ICD shocks and VA burden after LVAD implantation. PMID:27328958

  11. Early repolarization as a predictor of premature ventricular beats.

    PubMed

    Matoshvili, Z T; Petriashvili, Sh G; Archadze, A T; Azaladze, I G

    2015-02-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. Aim of this observational study was to compare number of premature ventricular beats in the different groups of patients with early repolarization. The result of this observational study shows that there are: 1,74 fold higher number of premature ventricular beats in 41-74 year subgroup VS 19-40 year subgroup; 1,31 fold higher number of premature ventricular beats in male subgroup VS female subgroup (But this difference is not statistically significant, because t=1,49, p=0,141); 2,85 fold higher number of premature ventricular beats in CAD+ERP subgroup VS ERP without CAD subgroup; 1,74 fold higher number of premature ventricular beats in HF+ERP subgroup VS ERP without HF subgroup; 1,81 fold higher number of premature ventricular beats in CAD+ERP subgroup VS CAD without ERP subgroup; 1,58 fold higher number of premature ventricular beats in HF+ERP subgroup VS HF without ERP subgroup; So, CAD+ERP is very arrhythmogenic condition, after this is HF+ERP, Then Age. This study shows that ERP independently increase number of PVB in different groups (CAD, HF). This is principally new and very important result. Also the number of patients is enough to make this conclusion.

  12. Surgical considerations for the explantation of the Parachute left ventricular partitioning device and the implantation of the HeartMate II left ventricular assist device

    PubMed Central

    Bansal, Shelley; Rosas, Paola C.; Mazzaferri, Ernest L.; Sai-Sudhakar, Chittoor B.

    2016-01-01

    Chronic heart failure is the leading cause of death in the world. With newer therapies, the burden of this disease has decreased; however, a significant number of patients remain refractive to existing therapies. Myocardial infarction often leads to ventricular remodeling and eventually contributes to heart failure. The Parachute™ (Cardiokinetix, Menlo Park, CA) is the first device designed for percutaneous ventricular restoration therapy, which reduces left ventricular volume and minimizes the risk of open surgical procedures. For the first time, we report a case of explantation of the Parachute ventricular partitioning device and transition to a HeartMate II™ left ventricular assist device and the surgical considerations for a successful outcome. PMID:27034560

  13. Central-Approach Surgical Repair of Coarctation of the Aorta with a Back-up Left Ventricular Assist Device for an Infant Presenting with Severe Left Ventricular Dysfunction

    PubMed Central

    Kim, Tae Hoon; Shin, Yu Rim; Kim, Young Sam; Kim, Do Jung; Kim, Hyohyun; Shin, Hong Ju; Htut, Aung Thein; Park, Han Ki

    2015-01-01

    A two-month-old infant presented with coarctation of the aorta, severe left ventricular dysfunction, and moderate to severe mitral regurgitation. Through median sternotomy, the aortic arch was repaired under cardiopulmonary bypass and regional cerebral perfusion. The patient was postoperatively supported with a left ventricular assist device for five days. Left ventricular function gradually improved, eventually recovering with the concomitant regression of mitral regurgitation. Prompt surgical repair of coarctation of the aorta is indicated for patients with severe left ventricular dysfunction. A central approach for surgical repair with a back-up left ventricular assist device is a safe and effective treatment strategy for these patients. PMID:26665108

  14. Surgical considerations for the explantation of the Parachute left ventricular partitioning device and the implantation of the HeartMate II left ventricular assist device.

    PubMed

    Ravi, Yazhini; Bansal, Shelley; Rosas, Paola C; Mazzaferri, Ernest L; Sai-Sudhakar, Chittoor B

    2016-04-01

    Chronic heart failure is the leading cause of death in the world. With newer therapies, the burden of this disease has decreased; however, a significant number of patients remain refractive to existing therapies. Myocardial infarction often leads to ventricular remodeling and eventually contributes to heart failure. The Parachute™ (Cardiokinetix, Menlo Park, CA) is the first device designed for percutaneous ventricular restoration therapy, which reduces left ventricular volume and minimizes the risk of open surgical procedures. For the first time, we report a case of explantation of the Parachute ventricular partitioning device and transition to a HeartMate II™ left ventricular assist device and the surgical considerations for a successful outcome. PMID:27034560

  15. Surgical considerations for the explantation of the Parachute left ventricular partitioning device and the implantation of the HeartMate II left ventricular assist device.

    PubMed

    Ravi, Yazhini; Bansal, Shelley; Rosas, Paola C; Mazzaferri, Ernest L; Sai-Sudhakar, Chittoor B

    2016-04-01

    Chronic heart failure is the leading cause of death in the world. With newer therapies, the burden of this disease has decreased; however, a significant number of patients remain refractive to existing therapies. Myocardial infarction often leads to ventricular remodeling and eventually contributes to heart failure. The Parachute™ (Cardiokinetix, Menlo Park, CA) is the first device designed for percutaneous ventricular restoration therapy, which reduces left ventricular volume and minimizes the risk of open surgical procedures. For the first time, we report a case of explantation of the Parachute ventricular partitioning device and transition to a HeartMate II™ left ventricular assist device and the surgical considerations for a successful outcome.

  16. Central-Approach Surgical Repair of Coarctation of the Aorta with a Back-up Left Ventricular Assist Device for an Infant Presenting with Severe Left Ventricular Dysfunction.

    PubMed

    Kim, Tae Hoon; Shin, Yu Rim; Kim, Young Sam; Kim, Do Jung; Kim, Hyohyun; Shin, Hong Ju; Htut, Aung Thein; Park, Han Ki

    2015-12-01

    A two-month-old infant presented with coarctation of the aorta, severe left ventricular dysfunction, and moderate to severe mitral regurgitation. Through median sternotomy, the aortic arch was repaired under cardiopulmonary bypass and regional cerebral perfusion. The patient was postoperatively supported with a left ventricular assist device for five days. Left ventricular function gradually improved, eventually recovering with the concomitant regression of mitral regurgitation. Prompt surgical repair of coarctation of the aorta is indicated for patients with severe left ventricular dysfunction. A central approach for surgical repair with a back-up left ventricular assist device is a safe and effective treatment strategy for these patients.

  17. An appreciation of some timing functions of a cardiac resynchronization device capable of left ventricular sensing.

    PubMed

    Barold, S Serge; Kucher, Andreas

    2016-09-01

    Some systems for cardiac resynchronization therapy (CRT) offer left ventricular sensing. This discussion with an illustrative case demonstrates that timing cycles in these devices may sometimes be difficult to understand because of left ventricular sensing. Programming of the left ventricular upper rate interval is crucial to optimize the resynchronization ability of the system. Interactions with the maximum sensor rate, the right ventricular upper rate interval, the left ventricular T wave protection algorithm, and the minimum ventricular tachycardia detection rate have to be considered. PMID:27605233

  18. Accelerated junctional rhythm and non-alternans repolarization lability precede ventricular tachycardia in Casq2−/− mice

    PubMed Central

    Mezu, Ure; Singh, Prabhpreet; Shusterman, Vladimir; Hwang, Hyun Seok; Knollmann, Bjorn C.; Němec, Jan

    2012-01-01

    Background Calsequestrin-2 (CASQ2) is a Ca2+ buffering protein of myocardial sarcoplasmic reticulum. CASQ2 mutations underlie a form of catecholaminergic polymorphic ventricular tachycardia (CPVT). The CPVT phenotype is recapitulated in Casq2−/− mice. Repolarization lability (RL) - beat-to-beat variability in the T wave morphology - has been reported in long-QT syndrome, but has not been evaluated in CPVT. Methods and Results ECG from Casq2−/− mice was evaluated with respect to heart rate (HR) and RL changes prior to onset of ventricular tachycardia (VT) to gain insight into arrhythmogenesis in CPVT. Telemetry from unrestrained mice (3-month-old males, 5 animals of each genotype) and ECG before and after isoproterenol administration in anesthetized mice was analyzed. Average HR in sinus rhythm (SR), occurrence of non-sinus rhythm and RL were quantified. HR was slower in Casq2−/− animals. Accelerated junctional rhythm (JR) occurred more frequently in Casq2−/− mice and often preceded VT. In Casq2−/− mice, HR increased prior to VT onset, prior to onset of JR and on transition from JR to VT. RL increased during progression from SR to VT and after isoproterenol administration in Casq2−/−, but not in Casq2+/+ animals. Isoproterenol did not increase repolarization alternans in either genotype. Conclusions Accelerated JR, likely caused by triggered activity in His/Purkinje system, occurs frequently in Casq2−/− mice. Absence of CASQ2 results in increased RL. Increase in HR and in RL precede onset of arrhythmias in this CPVT model. Non-alternans RL precedes ventricular arrhythmia in wider range of conditions than previously appreciated. PMID:22860618

  19. Right Ventricular Tissue Doppler in Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Barratt, Michael R.; Sargsyan, Ashot E.; Ebert, Douglas; Garcia, Kathleen M.; Martin, David S.; Dulchavsky, Scott A.; Duncan, J. Michael

    2009-01-01

    Tissue Doppler (TD) registers movement of a given sample of cardiac tissue throughout the cardiac cycle. TD spectra of the right ventricle (RV) were obtained from a long-duration ISS crewmember as a portion of an ongoing experiment ("Braslet" test objective). To our knowledge, this is the first report of RV TD conducted in space flight, and the data represent reproducibility and fidelity of this application in space and serve as the first "space normal" data set. Methods RV TD was performed by astronaut scientists remotely guided by an ultrasound expert from Mission Control Center, Houston, TX. In four of the subjects, RV TD was acquired from the free wall near the tricuspid annulus in two separate sessions 4 to 7 days apart. A fifth subject had only one session. All digital DICOM frames were exported for off-line analysis. Systolic (S ), early diastolic (E ) and late diastolic (A ) velocities were measured. RV Tei-index was calculated using diastolic and systolic time intervals as a combined measure of myocardial performance. Results and Discussion The mean values from the first 4 subjects (8 sessions) were used as the on-orbit reference data, and subject 5 was considered as a hypothetical patient for comparison (see Table). The greatest difference was in the early diastolic A (31 %) yet the standard deviation (a) for A amongst the reference subjects was 2.25 (mean = 16.02). Of interest is the Tei index, a simple and feasible indicator of overall ventricular function; it was similar amongst all the subjects. The late diastolic A seems to compensate for the variance in E . Normal Tei index for the RV is < 0.3, yet our data show all but one subject consistently above this level, notwithstanding their nominal responses to daily exercise in microgravity. These data remind us that the physiology of RV preload in altered gravity environments is still not completely understood.

  20. Voltage clamp experiments on ventricular myocardial fibres

    PubMed Central

    Beeler, G. W.; Reuter, H.

    1970-01-01

    1. A voltage clamp method utilizing a sucrose gap and glass microelectrodes was developed and used to study dog ventricular myocardial fibre bundles. The limitations and the reliability of this method are demonstrated by a series of tests. 2. A dynamic sodium current, excited at membrane potentials more positive than -65 mV, was measured. The equilibrium potential for this large, rapid inward current depends directly on [Na]o, shifting 29·0 ± 2·3 mV (± S.E. of mean), as opposed to a theoretically expected value of 30·6 mV, when [Na]o is reduced to 31% of normal. 3. Sodium current is inactivated by conditioning depolarizations. Complete inactivation occurs with conditioning potentials more positive than -45 mV, and 50% inactivation occurs at about -55 mV. The location of the inactivation curve shifts along the voltage axis, when [Ca]o is varied between 0·2 and 7·2 mM. 4. A second, much smaller and slower net inward current, with a threshold around -30 mV, and an equilibrium potential above +40 mV was also observed. 5. The `steady-state' current—voltage relationship (after 300-600 msec) exhibits inward-going (anomalous) rectification with negative slope between -50 and -25 mV. 6. A small, very slowly developing component of outward current was observed at inside positive potentials. The equilibrium potential for this current, although slightly dependent on [K]o, is neither identical with the potassium equilibrium potential nor with the resting potential in normal Tyrode solution. 7. Anatomical limitations, primarily resistance in the extracellular space within the bundle, prevent complete characterization of the rapid, large sodium current, but do not limit the application of the clamp method to the study of other, smaller and slower currents. The evidence for this is discussed extensively in the Appendix. PMID:5503866

  1. Air pollution effects on ventricular repolarization.

    PubMed

    Lux, Robert L; Pope, C Arden

    2009-05-01

    We conducted a retrospective study of a set of previously published electrocardiographic data to investigate the possible direct association between levels of particulate air pollution and changes in ventricular repolarization -- the cardiac electrophysiologic process that manifests itself as the T wave* of the electrocardiogram (ECG) and that is definitively linked to and responsible for increased arrhythmogenesis. The published findings from this data set demonstrated a clear cardiac effect, namely, a reduction in heart rate variability (HRV) parameter values with increased levels of particulate air pollution (Pope et al. 2004), suggesting possible arrhythmogenic effects. Given this positive finding and the well-established sensitivity of cardiac repolarization to physiologic, pharmacologic, and neurologic interventions, and in light of emerging novel tools for assessing repolarization, we hypothesized that high levels of particulate air pollution would alter repolarization independent of changes in heart rate and, consequently, would increase arrhythmogenic risk. The likely mechanism of any deleterious effects on repolarization would be alteration of sodium, calcium, and potassium channels. The channel's structure, function, and kinetics are responsible for generating the cellular action potentials, which, when summed over the entire heart, result in the waves recorded by the ECG. A positive finding would provide evidence that increased levels of air pollution may be directly linked to increases in arrhythmogenic risk and, potentially, sudden cardiac death. The study population consisted of 88 nonsmoking, elderly subjects in whom multiple, continuous, 24-hour, 2-channel ECG recordings were collected, along with blood samples to evaluate inflammatory mechanisms (not pursued in the current study). The concentration of fine particulate matter (PM2.5, particulate matter with an aerodynamic diameter < or = 2.5 microm) in daily samples was measured or estimated and

  2. Heterogeneity of Left Ventricular Signal Characteristics in Response to Acute Vagal Stimulation during Ventricular Fibrillation in Dogs

    PubMed Central

    Nazeri, Alireza; Elayda, MacArthur A.; Dragnev, Lubomir; Frank, Christopher M.; Qu, Jihong; Afonso, Valtino X.; Rasekh, Abdi; Saeed, Mohammad; Cheng, Jie; Shuraih, Mossaab; Massumi, Ali; Razavi, Mehdi

    2011-01-01

    Studies have shown that long-term vagal stimulation is protective against ventricular fibrillation; however, the effects of acute vagal stimulation during ventricular fibrillation in the normal heart have not been investigated. We examined the effects of acute vagal stimulation on ventricular fibrillation in a canine model. In 4 dogs, we induced 30-second periods of ventricular fibrillation by means of intraventricular pacing. During 2 of the 4 periods of fibrillation that we analyzed, vagal stimulation was delivered through electrodes in the caudal ends of the vagus nerves. Noncontact unipolar electrograms were recorded from 3 ventricular regions: the basal septum, apical septum, and lateral free wall. We then computed the most frequent cycle length, mean organization index, and mean electrogram amplitude for each region. During fibrillation, vagal stimulation shortened the most frequent cycle lengths in the basal septum (P=0.02) and apical septum (P=0.0001), but not in the lateral wall (P=0.46). In addition, vagal stimulation significantly reduced the mean organization indices in the apical septum (P <0.001) and lateral wall (P <0.001), but not in the basal septum (P=0.19). Furthermore, vagal stimulation raised the mean electrogram amplitude in the basal septum (P <0.01) but lowered it substantially in the apical septum (P=0.00005) and lateral wall (P=0.00003). We conclude that vagal stimulation acutely affects the characteristics of ventricular fibrillation in canine myocardium in a spatially heterogeneous manner. This nonuniformity of response may have implications with regard to manipulating the autonomic system as a means of modifying the substrate for ventricular dysrhythmias. PMID:22199421

  3. Correlation of Left Ventricular Diastolic Function and Left Ventricular Geometry in Patients with Obstructive Sleep Apnoea Syndrome

    PubMed Central

    Wang, J; Zhang, H; Wu, C; Han, J; Guo, Z; Jia, C; Yang, L; Hao, Y; Xu, K; Liu, X; Si, J

    2015-01-01

    ABSTRACT Background: The aim of this study is to evaluate the correlation of the left ventricular diastolic function and the left ventricular geometry in patients with obstructive sleep apnoea syndrome (OSAS) by echocardiography. Methods: The 181 patients diagnosed with OSAS were divided into the normal geometry group (NG), the concentric remodelling group (CR), the eccentric hypertrophy group (EH) and the concentric hypertrophy group (CH). Pearson correlation analysis and multiple linear regression analysis were performed toward the correlation of the left ventricular diastolic function and the left ventricular geometry. Results: The E peak in the EH and CH group was significantly reduced, with significant difference; the E/A, Em, Am and Em/Am was reduced in the order of the CR, EH and CH groups, while E/Em was increased, and the difference was significant. Pearson correlation analysis revealed that the Em/Am showed significant negative correlations with the left ventricular mass index (LVMI) [r = −0.419] and relative wall thickness (RWT) [r = −0.289], while the E/Em was significantly positively correlated with the LVMI (r = 0.638) and RWT [r = 0.328] (p < 0.001). Multiple linear regression analysis revealed that LVMI and RWT had influence on the Em/Am and E/Em (r2 = 0.402, r2 = 0.107, p < 0.001). The left ventricular diastolic dysfunction was the worst in the CH group. Conclusions: There was correlation between the left ventricular diastolic dysfunction and the changes in cardiac geometry. PMID:26360680

  4. Survival and complications following ventricular assist pumping for cardiogenic shock.

    PubMed Central

    Pennock, J L; Pierce, W S; Wisman, C B; Bull, A P; Waldhausen, J A

    1983-01-01

    Thirty patients (pts) have undergone ventricular assist pumping for up to 25.4 days (mean 6.8 days). Twenty-eight pts could not be weaned from cardiopulmonary bypass (CPB) after open heart operations and two pts sustained myocardial infarctions (MI), with cardiogenic shock unresponsive to medical therapy previous to surgery. Twenty-two pts required left ventricular assistance (LVA); 55% (12/22) were weaned from the pump and 32% (7/22) survived. Two pts required right ventricular assistance (RVA); both were weaned from the pump and survived. Six pts required right and left ventricular assistance (BVA) and none survived. Postoperative survival for program years 1976 through 1979 (14 pts) was 14% (2/14). Postoperative survival for program years 1980 through 1982 (16 pts) was 44% (7/16), reflecting improved pump insertion techniques (left atrial cannulation) and pt management. Since 1980, 12 pts have required LVA, nine have been weaned from the pump, and six pts have survived (50%). One pt has required RVA and has survived, and three pts requiring BVA did not survive. Seven pts have been alive and well 5, 9, 14, 19, 24, 30 and 36 months after surgery. Five are NYHA functional Class I status and two pts are NYHA Class II status. Current data indicates that single ventricular assistance in pts who cannot be weaned from CPB is "reasonable and therapeutic treatment to extend life." Images Fig. 1. PMID:6625718

  5. Experience with the Sarns centrifugal pump in postcardiotomy ventricular failure.

    PubMed

    Curtis, J J; Walls, J T; Schmaltz, R; Boley, T M; Nawarawong, W; Landreneau, R J

    1992-09-01

    The reported clinical use of the Sarns centrifugal pump (Sarns, Inc./3M, Ann Arbor, Mich.) as a cardiac assist device for postcardiotomy ventricular failure is limited. During a 25-month period ending November 1988, we used 40 Sarns centrifugal pumps as univentricular or biventricular cardiac assist devices in 27 patients who could not be weaned from cardiopulmonary bypass despite maximal pharmacologic and intraaortic balloon support. Eighteen men and nine women with a mean age of 60.4 years (28 to 83) required assistance. Left ventricular assist alone was used in 12 patients, right ventricular assist in 2, and biventricular assist in 13. The duration of assist ranged from 2 to 434 hours (median 45). Centrifugal assist was successful in weaning 100% of the patients. Ten of 27 patients (37%) improved hemodynamically, allowing removal of the device(s), and 5 of 27 (18.5%) survived hospitalization. Survival of patients requiring left ventricular assist only was 33.3% (4/12). Complications were common and included renal failure, hemorrhage, coagulopathy, ventricular arrhythmias, sepsis, cerebrovascular accident, and wound infection. During 3560 centrifugal pump hours, no pump thrombosis was observed. The Sarns centrifugal pump is an effective assist device when used to salvage patients who otherwise cannot be weaned from cardiopulmonary bypass. Statistical analysis of preoperative patient characteristics, operative risk factors, and postoperative complications failed to predict which patients would be weaned from cardiac assist or which would survive.

  6. Ventricular arrhythmias in congestive heart failure: clinical significance and management.

    PubMed Central

    Khoshnevis, G R; Massumi, A

    1999-01-01

    The benefit of defibrillator therapy has been well established for patients with LV dysfunction (ejection fraction less than 35%), coronary artery disease, NSVT, and inducible and nonsuppressible ventricular tachycardia. Implantable cardioverter-defibrillator therapy is also indicated for all CHF patients in NYHA functional classes I, II, and III who present with aborted sudden cardiac death, or ventricular fibrillation, or hemodynamically unstable ventricular tachycardia--and also in patients with syncope with no documented ventricular tachycardia but with inducible ventricular tachycardia at electrophysiology study. The ongoing MADIT II trial was designed to evaluate the benefit of prophylactic ICD implantation in these patients (ejection fraction less than 30%, coronary artery disease, and NSVT) without prior risk stratification by PES. The CABG Patch trial concluded that prophylactic placement of an ICD during coronary artery bypass grafting in patients with low ejection fraction and abnormal SAECG is not justifiable. Except for the indications described above, ICD implantation has not been proved to be beneficial as primary or secondary therapy. Until more data are available, patients should be encouraged to enroll in the ongoing clinical trials. PMID:10217470

  7. Idiopathic ventricular tachycardia: feasibility and efficacy of catheter ablation.

    PubMed

    Velazquez Rodriguez, E; Frank, R; Fontaine, G; Tonet, J; Lascault, G; Rosas, F; Eslami, M; Nakazato, Y

    1995-01-01

    Idiopathic ventricular tachycardia is a well described syndrome of both left and right ventricular origin. This study reports the feasibility and efficacy of catheter ablation in this entity. Fourteen patients (mean age 30 +/- 10 years of age) and six patients (mean age 51 +/- 9 years of age) underwent endocardial catheter ablation with either direct-current shocks and radiofrequency energy, respectively. Earliest right and left ventricular activation and endocardial mapping during tachycardia were made to localize the site of ventricular tachycardia origin. The overall clinical efficacy was 93% for direct-current method with a mean number of shocks of 3.3 +/- 0.9/patient after a mean follow-up of 38 +/- 25 months. Radiofrequency ablation achieved an overall clinical efficacy of 83.6% with a mean of 3.2 pulses/patient during a follow-up of 10.5 +/- 4 months. The isoenzyme MB fraction of peak creatine kinase after ablation was less than 5%. There were no complications in any patient who underwent radiofrequency energy. Endocardial catheter ablation is feasible in patients with idiopathic ventricular tachycardia. Both methods are highly effective but radiofrequency energy is most desirable because of its lack of barotrauma, and may be considered as early therapy. PMID:7620280

  8. Left ventricular systolic and diastolic function in hyperthyroidism

    SciTech Connect

    Friedman, M.J.; Okada, R.D.; Ewy, G.A.; Hellman, D.J.

    1982-12-01

    In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive iodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle.

  9. Ventricular dysfunction following direct-current shock atrioventricular junction ablation.

    PubMed

    Warren, R J; Vohra, J K; Chan, W; Lichtenstein, M; Mond, H G; Hunt, D

    1991-02-01

    Catheter-induced His bundle ablation for refractory supraventricular arrhythmias is most commonly performed with direct-current shock energy of 200-300 joules. The high energy pulse delivered by direct-current shock produces a lesion in the atrioventricular node by fulguration, with the residual energy being dissipated as a pressure wave. The effect of direct-current shock His bundle ablation on global and regional ventricular function was assessed in 14 consecutive patients by radionuclide ventriculography performed before and after ablation and again three months later. All studies were performed with ventricular pacing at 110 bpm. Global left ventricular ejection fraction was found to be significantly reduced at the three month study (0.43 +/- 0.03 vs 0.50 +/- 0.03, pre ablation, p = 0.02). A significant reduction in wall-motion score was also seen in six of the seven patients who had normal wall motion in pacing rhythm prior to ablation. Deterioration was mainly seen at the left and right ventricular apices. The observed reduction in ventricular function that follows direct-current shock His bundle ablation may result from myocardial damage from electro-coagulation or from barotrauma and supports continued investigation into alternative, less traumatic energy sources for the procedure. PMID:2036072

  10. Ventricular dysfunction in children with obstructive sleep apnea: radionuclide assessment

    SciTech Connect

    Tal, A.; Leiberman, A.; Margulis, G.; Sofer, S.

    1988-01-01

    Ventricular function was evaluated using radionuclide ventriculography in 27 children with oropharyngeal obstruction and clinical features of obstructive sleep apnea. Their mean age was 3.5 years (9 months to 7.5 years). Conventional clinical assessment did not detect cardiac involvement in 25 of 27 children; however, reduced right ventricular ejection fraction (less than 35%) was found in 10 (37%) patients (mean: 19.5 +/- 2.3% SE, range: 8-28%). In 18 patients wall motion abnormality was detected. In 11 children in whom radionuclide ventriculography was performed before and after adenotonsillectomy, right ventricular ejection fraction rose from 24.4 +/- 3.6% to 46.7 +/- 3.4% (P less than 0.005), and in all cases wall motion showed a definite improvement. In five children, left ventricular ejection fraction rose greater than 10% after removal of oropharyngeal obstruction. It is concluded that right ventricular function may be compromised in children with obstructive sleep apnea secondary to adenotonsillar hypertrophy, even before clinical signs of cardiac involvement are present.

  11. Surgical ventricular restoration for the treatment of heart failure.

    PubMed

    Buckberg, Gerald; Athanasuleas, Constantine; Conte, John

    2012-12-01

    Heart failure (HF) is an emerging epidemic affecting 15 million people in the USA and Europe. HF-related mortality was unchanged between 1995 and 2009, despite a decrease in the incidence of cardiovascular disease. Conventional explanations include an aging population and improved treatment of acute myocardial infarction and HF. An adverse relationship between structure and function is the central theme in patients with systolic dysfunction. The normal elliptical ventricular shape becomes spherical in ischemic, valvular, and nonischemic dilated cardiomyopathy. Therapeutic decisions should be made on the basis of ventricular volume rather than ejection fraction. When left ventricular end-systolic volume index exceeds 60 ml/m², medical therapy, CABG surgery, and mitral repair have limited benefit. This form-function relationship can be corrected by surgical ventricular restoration (SVR), which returns the ventricle to a normal volume and shape. Consistent early and late benefits in the treatment of ischemic dilated cardiomyopathy with SVR have been reported in >5,000 patients from various international centers. The prospective, randomized STICH trial did not confirm these findings and the reasons for this discrepancy are examined in detail. Future surgical options for SVR in nonischemic and valvular dilated cardiomyopathy, and its integration with left ventricular assist devices and cell therapy, are described.

  12. Inhibition of premature ventricular extrastimuli by subthreshold conditioning stimuli.

    PubMed

    Skale, B T; Kallok, M J; Prystowsky, E N; Gill, R M; Zipes, D P

    1985-07-01

    The purpose of this study was to determine whether trains of subthreshold high frequency conditioning stimuli (333 Hz, 1 ms duration, 2 ms interval) delivered to the canine ventricle inhibited the response to a premature stimulus (S2) more effectively than did a single subthreshold conditioning stimulus. It was found that trains of conditioning stimuli (mean 1.21 mA) inhibited the response to S2 152 ms beyond expiration of the ventricular effective refractory period, whereas a single conditioning stimulus inhibited S2 only 20 ms or less beyond the ventricular effective refractory period. In late diastole, trains of conditioning stimuli failed to inhibit S2 when the train of stimuli caused ventricular depolarization or the latter occurred in response to the next sinus impulse. Trains of conditioning stimuli did not induce ventricular arrhythmias. Lidocaine or autonomic blockade did not alter the response to trains of conditioning stimuli. Trains of conditioning stimuli or a single conditioning stimulus inhibited the response to S2 only when they were delivered at the same electrode site. By lengthening the ventricular effective refractory period, trains of conditioning stimuli could prevent or terminate tachycardias, but this possibility is constrained, at present, by the spatial limitations of the technique.

  13. Positive T wave overshoot as a sign of ventricular enlargement.

    PubMed

    Short, D; Weir, J

    1984-03-01

    A consecutive series of 86 patients with an inverted T wave showing terminal positivity (overshoot) of a specific pattern in the resting electrocardiogram were studied. Patients with bundle branch block or electrocardiographic evidence of acute infarction and those taking digoxin or a similar drug were excluded. In 67 patients the heart was examined by echocardiography and in a further two by direct inspection. Sixty six of the 69 patients had an abnormal thickness of the left (or right) ventricle or a calculated left ventricular mass greater than 200 g. Seven of the patients examined by echocardiography had clinically pure ischaemic heart disease; all showed evidence of left ventricular enlargement. In only 39 of the 63 patients with anatomical evidence of left ventricular hypertrophy or dilatation did the electrocardiogram satisfy the standard voltage criterion of left ventricular hypertrophy. In the absence of acute infarction, bundle branch block, or digitalisation positive T wave overshoot of the pattern described is a sign of increased ventricular mass. PMID:6230092

  14. Ventricular dysfunction following direct-current shock atrioventricular junction ablation.

    PubMed

    Warren, R J; Vohra, J K; Chan, W; Lichtenstein, M; Mond, H G; Hunt, D

    1991-02-01

    Catheter-induced His bundle ablation for refractory supraventricular arrhythmias is most commonly performed with direct-current shock energy of 200-300 joules. The high energy pulse delivered by direct-current shock produces a lesion in the atrioventricular node by fulguration, with the residual energy being dissipated as a pressure wave. The effect of direct-current shock His bundle ablation on global and regional ventricular function was assessed in 14 consecutive patients by radionuclide ventriculography performed before and after ablation and again three months later. All studies were performed with ventricular pacing at 110 bpm. Global left ventricular ejection fraction was found to be significantly reduced at the three month study (0.43 +/- 0.03 vs 0.50 +/- 0.03, pre ablation, p = 0.02). A significant reduction in wall-motion score was also seen in six of the seven patients who had normal wall motion in pacing rhythm prior to ablation. Deterioration was mainly seen at the left and right ventricular apices. The observed reduction in ventricular function that follows direct-current shock His bundle ablation may result from myocardial damage from electro-coagulation or from barotrauma and supports continued investigation into alternative, less traumatic energy sources for the procedure.

  15. Acceleration of cerebral ventricular expansion in the Cardiovascular Health Study.

    PubMed

    Carmichael, Owen T; Kuller, L H; Lopez, O L; Thompson, P M; Dutton, R A; Lu, A; Lee, S E; Lee, J Y; Aizenstein, H J; Meltzer, C C; Liu, Y; Toga, A W; Becker, J T

    2007-09-01

    Interactions between prevalent late-life medical conditions and expansion of the cerebral ventricles are not well understood. Thirty elderly subjects received three magnetic resonance (MR) scans each, in 1997-1999, 2002-2004, and 2003-2005. A linear expansion model of MR-measured lateral ventricle volume was estimated for each subject by fitting a line to a plot of their 1997-1999 and 2002-2004 volumes as a function of time. Acceleration in ventricular expansion was defined as the deviation between the 2003-2005 volumes measured from MR and the 2003-2005 volumes predicted by the linear expansion model. Ventricular acceleration was analyzed in a multivariate model with age, race, history of heart disease, diabetes, and hypertension as fixed effects. Ventricular acceleration was significantly higher in non-whites, diabetics, and those without heart disease (p<0.05). Ventricular acceleration was higher in subjects with a history of hypertension, but the difference was not statistically significant (p=0.08). Acceleration of ventricular expansion in the elderly may be related to demographic and cardiovascular factors.

  16. Left ventricular systolic and diastolic function in hyperthyroidism.

    PubMed

    Friedman, M J; Okada, R D; Ewy, G A; Hellman, D J

    1982-12-01

    In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive iodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle.

  17. Structural Polymorphism in Amyloids

    PubMed Central

    Jones, Eric M.; Wu, Bo; Surewicz, Krystyna; Nadaud, Philippe S.; Helmus, Jonathan J.; Chen, Shugui; Jaroniec, Christopher P.; Surewicz, Witold K.

    2011-01-01

    The C-terminally-truncated human prion protein variant Y145Stop (or PrP23–144), associated with a familial prion disease, provides a valuable model for studying the fundamental properties of protein amyloids. In previous solid-state NMR experiments, we established that the β-sheet core of the PrP23–144 amyloid is composed of two β-strand regions encompassing residues ∼113–125 and ∼130–140. The former segment contains a highly conserved hydrophobic palindrome sequence, 113AGAAAAGA120, which has been considered essential to PrP conformational conversion. Here, we examine the role of this segment in fibrillization of PrP23–144 using a deletion variant, Δ113–120 PrP23–144, in which the palindrome sequence is missing. Surprisingly, we find that deletion of the palindrome sequence affects neither the amyloidogenicity nor the polymerization kinetics of PrP23–144, although it does alter amyloid conformation and morphology. Using two-dimensional and three-dimensional solid-state NMR methods, we find that Δ113–120 PrP23–144 fibrils contain an altered β-core extended N-terminally to residue ∼106, encompassing residues not present in the core of wild-type PrP23–144 fibrils. The C-terminal β-strand of the core, however, is similar in both fibril types. Collectively, these data indicate that amyloid cores of PrP23–144 variants contain “essential” (i.e. nucleation-determining) and “nonessential” regions, with the latter being “movable” in amino acid sequence space. These findings reveal an intriguing new mechanism for structural polymorphism in amyloids and suggest a potential means for modulating the physicochemical properties of amyloid fibrils without compromising their polymerization characteristics. PMID:22002245

  18. Role of left ventricular twist mechanics in cardiomyopathies, dance of the helices

    PubMed Central

    Kauer, Floris; Geleijnse, Marcel Leonard; van Dalen, Bastiaan Martijn

    2015-01-01

    Left ventricular twist is an essential part of left ventricular function. Nevertheless, knowledge is limited in “the cardiology community” as it comes to twist mechanics. Fortunately the development of speckle tracking echocardiography, allowing accurate, reproducible and rapid bedside assessment of left ventricular twist, has boosted the interest in this important mechanical aspect of left ventricular deformation. Although the fundamental physiological role of left ventricular twist is undisputable, the clinical relevance of assessment of left ventricular twist in cardiomyopathies still needs to be established. The fact remains; analysis of left ventricular twist mechanics has already provided substantial pathophysiological understanding on a comprehensive variety of cardiomyopathies. It has become clear that increased left ventricular twist in for example hypertrophic cardiomyopathy may be an early sign of subendocardial (microvascular) dysfunction. Furthermore, decreased left ventricular twist may be caused by left ventricular dilatation or an extensive myocardial scar. Finally, the detection of left ventricular rigid body rotation in noncompaction cardiomyopathy may provide an indispensible method to objectively confirm this difficult diagnosis. All this endorses the value of left ventricular twist in the field of cardiomyopathies and may further encourage the implementation of left ventricular twist parameters in the “diagnostic toolbox” for cardiomyopathies. PMID:26322187

  19. Three-dimensional CFD/MRI modeling reveals that ventricular surgical restoration improves ventricular function by modifying intraventricular blood flow.

    PubMed

    Khalafvand, S S; Zhong, L; Ng, E Y K

    2014-10-01

    Surgical ventricular restoration (SVR) is designed to normalize distorted ventricular shape and size in patients with left ventricular (LV) dysfunction and akinetic and dyskinetic segments. This study is aimed to quantify the characteristics of LV as a pump for a case before and after SVR, which is followed by coronary artery bypass grafting (CABG). We hypothesize that SVR+CABG improves heart flow. A patient with heart failure had magnetic resonance (MR) scans before and 4 months after SVR. LV endocardial geometries were semi-automated segmented and reconstructed using our customized algorithm. The arbitrary Lagrangian-Eulerian formulation of Navier-Stokes equations was solved to derive the flow patterns and calculate pressure differences in LV. After SVR, LV ejection fraction increased from 34% to 48% in patient but was still lower than normal (70%). Second, LV vortices were stronger than pre-surgery but still weaker than normal. The maximum pressure differences between ventricular base and apex increased from 180 to 400 Pa during diastole, from 252 to 560 Pa during systole, respectively. As anticipated, SVR reduced LV volumes and augmented LV ejection fraction. Three-dimensional CFD/MRI modeling suggests that improved diastolic and systolic ventricular function after SVR is associated with changes in intraventricular blood flow.

  20. Model for end-stage liver disease predicts right ventricular failure in patients with left ventricular assist devices.

    PubMed

    Yost, Gardner L; Coyle, Laura; Bhat, Geetha; Tatooles, Antone J

    2016-03-01

    High rates of right ventricular failure continue to affect postoperative outcomes in patients implanted with left ventricular assist devices (LVADs). Development of right ventricular failure and implantation with right ventricular assist devices is known to be associated with significantly increased mortality. The model for end-stage liver disease (MELD) score is an effective means of evaluating liver dysfunction. We investigated the prognostic utility of postoperative MELD on post-LVAD implantation outcomes. MELD scores, demographic data, and outcomes including length of stay, survival, and postoperative right ventricular failure were collected for 256 patients implanted with continuous flow LVADs. Regression and Kaplan-Meier analyses were used to investigate the relationship between MELD and all outcomes. Increased MELD score was found to be an independent predictor of both right heart failure and necessity for RVAD implantation (OR 1.097, CI 1.040-1.158, p = 0.001; OR 1.121, CI 1.015, p = 0.024, respectively). Patients with RV failure and who underwent RVAD implantation had reduced postoperative survival compared to patients with RV dysfunction (no RV failure = 651.4 ± 609.8 days, RV failure = 392.6 ± 444.8 days, RVAD = 89.3 ± 72.8 days; p < 0.001). In conclusion, MELD can be used to reliably predict postoperative right heart failure and the necessity for RVAD implantation. Those patients with RV failure and RVADs experience significantly increased postoperative mortality compared to those without RV dysfunction. PMID:26187243

  1. 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.

  2. Laboratory Markers of Ventricular Arrhythmia Risk in Renal Failure

    PubMed Central

    2014-01-01

    Sudden cardiac death continues to be a major public health problem. Ventricular arrhythmia is a main cause of sudden cardiac death. The present review addresses the links between renal function tests, several laboratory markers, and ventricular arrhythmia risk in patients with renal disease, undergoing or not hemodialysis or renal transplant, focusing on recent clinical studies. Therapy of hypokalemia, hypocalcemia, and hypomagnesemia should be an emergency and performed simultaneously under electrocardiographic monitoring in patients with renal failure. Serum phosphates and iron, PTH level, renal function, hemoglobin and hematocrit, pH, inflammatory markers, proteinuria and microalbuminuria, and osmolarity should be monitored, besides standard 12-lead ECG, in order to prevent ventricular arrhythmia and sudden cardiac death. PMID:24982887

  3. Premature ventricular complex-induced chronic cough and cough syncope.

    PubMed

    Stec, S; Dabrowska, M; Zaborska, B; Bielicki, P; Maskey-Warzechowska, M; Tarnowski, W; Chazan, R; Kulakowski, P

    2007-08-01

    The present case study reports a case of chronic cough and cough syncope associated with frequent premature ventricular complexes (PVCs). Careful analysis of cough-related symptoms and ECG monitoring led to the suspicion of PVC-induced cough. A coincidence between PVCs and episodes of cough was also documented by a portable multichannel recorder. Moreover, Doppler echocardiography revealed a PVC-induced transient increase in the pulmonary artery blood flow. After exclusion of other possible aetiologies, complete relief of chronic cough and cough syncope was achieved by radiofrequency ablation of the arrhythmogenic focus located in the right ventricular outflow tract. Premature ventricular complexes should be considered as a cause of chronic cough and cough syncope and an interdisciplinary cooperation can lead to successful diagnosis and treatment of this condition.

  4. A case of arrhythmogenic right ventricular cardiomyopathy—Naxos disease

    PubMed Central

    Saravanan, R.R.; Amuthan, V.; Janarthanan, R.A.; Balasubramanian, S.; Mohamed, S. Naina

    2012-01-01

    We present a case of arrhythmogenic right ventricular cardiomyopathy (ARVC)—Naxos disease. The patient is 21-year-old male with no history of previous heart disease admitted in a private hospital for rhythm disorder in heart. The condition was diagnosed as ventricular tachycardia (VT) and was treated with cardioversion. The patient was referred to our hospital for further evaluation. On examination patient had palmoplantar keratoderma, wooly hair, and dystrophic nails. The cardiovascular system examination was clinically normal. His electrocardiogram showed epsilon wave in lead V1; echocardiography showed hypo-echogenic tissues in the right ventricular (RV) apex and free wall; magnetic resonance imaging (MRI) investigation revealed fibrofatty replacement of RV free wall and dyskinetic RV wall with diastolic outbulging. PMID:22572432

  5. Passive ventricular remodeling in cardiac disease: focus on heterogeneity

    PubMed Central

    Kessler, Elise L.; Boulaksil, Mohamed; van Rijen, Harold V. M.; Vos, Marc A.; van Veen, Toon A. B.

    2014-01-01

    Passive ventricular remodeling is defined by the process of molecular ventricular adaptation to different forms of cardiac pathophysiology. It includes changes in tissue architecture, such as hypertrophy, fiber disarray, alterations in cell size and fibrosis. Besides that, it also includes molecular remodeling of gap junctions, especially those composed by Connexin43 proteins (Cx43) in the ventricles that affect cell-to-cell propagation of the electrical impulse, and changes in the sodium channels that modify excitability. All those alterations appear mainly in a heterogeneous manner, creating irregular and inhomogeneous electrical and mechanical coupling throughout the heart. This can predispose to reentry arrhythmias and adds to a further deterioration into heart failure. In this review, passive ventricular remodeling is described in Hypertrophic Cardiomyopathy (HCM), Dilated Cardiomyopathy (DCM), Ischemic Cardiomyopathy (ICM), and Arrhythmogenic Cardiomyopathy (ACM), with a main focus on the heterogeneity of those alterations mentioned above. PMID:25566084

  6. Revascularization in severe left ventricular dysfunction.

    PubMed

    Velazquez, Eric J; Bonow, Robert O

    2015-02-17

    The highest-risk patients with heart failure with reduced ejection fraction are those with ischemic cardiomyopathy and severe left ventricular systolic dysfunction (ejection fraction≤35%). The cornerstone of treatment is guideline-driven medical therapy for all patients and implantable device therapy for appropriately selected patients. Surgical revascularization offers the potential for improved survival and quality of life, particularly in patients with more extensive multivessel disease and the greatest degree of left ventricular systolic dysfunction and remodeling. These are also the patients at greatest short-term risk of mortality with coronary artery bypass graft surgery. The short-term risks of surgery need to be balanced against the potential for long-term benefit. This review discusses the evolving data on the role of surgical revascularization, surgical ventricular reconstruction, and mitral valve surgery in this high-risk patient population.

  7. Polymer-based restoration of left ventricular mechanics.

    PubMed

    Lee, Randall J; Hinson, Andy; Helgerson, Sam; Bauernschmitt, Robert; Sabbah, Hani N

    2013-01-01

    Heart failure continues to be a major health care concern with relatively few options for severely advanced heart failure patients. The hallmark of heart failure is the progressive dilatation of the left ventricle, thinning of the left ventricular wall leading to increased wall stress and increased myocardial oxygen consumption. Applying Laplace's law to the failing dilated ventricle, left ventricular augmentation utilizes a tissue engineering strategy to increase wall thickness and reduce chamber diameter, resulting in a decrease in wall stress and improved left ventricular function. A review of the rationale for an in situ tissue engineering approach for this treatment of heart failure and early clinical results of the Algisyl-LVR™ program are presented. PMID:22469060

  8. Postinfarct Left Ventricular Remodelling: A Prevailing Cause of Heart Failure

    PubMed Central

    Galli, Alessio; Lombardi, Federico

    2016-01-01

    Heart failure is a chronic disease with high morbidity and mortality, which represents a growing challenge in medicine. A major risk factor for heart failure with reduced ejection fraction is a history of myocardial infarction. The expansion of a large infarct scar and subsequent regional ventricular dilatation can cause postinfarct remodelling, leading to significant enlargement of the left ventricular chamber. It has a negative prognostic value, because it precedes the clinical manifestations of heart failure. The characteristics of the infarcted myocardium predicting postinfarct remodelling can be studied with cardiac magnetic resonance and experimental imaging modalities such as diffusion tensor imaging can identify the changes in the architecture of myocardial fibers. This review discusses all the aspects related to postinfarct left ventricular remodelling: definition, pathogenesis, diagnosis, consequences, and available therapies, together with experimental interventions that show promising results against postinfarct remodelling and heart failure. PMID:26989555

  9. 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.

  10. Noninvasive evaluation of ventricular hypertrophy in professional athletes.

    PubMed

    Roeske, W R; O'Rourke, R A; Klein, A; Leopold, G; Karliner, J S

    1976-02-01

    Athletes often exhibit ECG findings which are considered to be abnormal. Therefore, we used noninvasive graphic methods to study 42 active professional male basketball players, ranging in age from 21 to 31 years, without clinically evident heart disease. Of the 42, 11 (25%) met the Romhilt-Estes ECG voltage criteria for left ventricular hypertrophy, and 12 (29%) satisfied VCG criteria for left ventricular enlargement; nine (21%) had left ventricular hypertrophy by both methods. In 33 subjects (79%) the 0.04 sec vector in the horizontal plane was anterior, and 29 of these exhibited one or more standard criteria for right ventricular enlargement; the ECG and VCG were concordant for right ventricular hypertrophy in 16 subjects (38%). Submaximal treadmill exercise tests (Bruce protocol) were normal in eight athletes, while in one subject ventricular premature beats occurred during the test. In 24 of 25 athletes (96%) from whom phonocardiograms were obtained a third heart sound was recorded, while in 14 (56%), a fourth heart sound was present. Of the 14 athletes who had a fourth heart sound, 12 (86%) had either ECG or VCG evidence of ventricular hypertrophy. Only four of 23 athletes had an increased cardiothoracic ratio (greater than .50) on routine chest X-ray. Ten athletes and ten control subjects matched for height, weight and body surface area had echocardiograms satisfactory for analysis. The left ventricular end-diastolic dimension in the athletes averaged 53.7 +/- 1.3 (SE) mm compared with a value of 49.9 +/- 0.7 mm in the control subjects (P less than 0.02), and was increased (greater than or equal to 56 mm) in four. Left ventricular posterior wall thickness averaged 11.1 +/- 0.6 mm, compared with a value of 9.8 +/- 0.5 mm in the control subjects (P less than 0.05), and was increased (greater than or equal to 11 mm) in six athletes. The right ventricular end-diastolic dimension averaged 20.8 +/- 1.1 mm compared with a value of 12.9 +/- 2.2 mm in the controls (P

  11. Sudden death in right ventricular dysplasia with minimal gross abnormalities.

    PubMed

    Burke, A P; Robinson, S; Radentz, S; Smialek, J; Virmani, R

    1999-03-01

    Arrhythmogenic right ventricular cardiomyopathy is emerging as a relatively common cause of exercise-induced sudden death in the young. The diagnostic criteria at autopsy are, however, not fully established, leading to both over- and underdiagnosis. We report a young man and a young woman dying suddenly of right ventricular dysplasia during exercise, in whom the gross autopsy findings in the right ventricle were minimal or even absent. However, the histologic features in both right and left ventricles were typical of the disease, and consisted of fibrofatty infiltrates with typical myocyte degeneration of the right ventricle and subepicardial regions of the left ventricle. These cases illustrate that microscopic findings are diagnostic and may be present in the absence of gross findings. Marked fat replacement is not essential for the diagnosis of right ventricular dysplasia, and the right ventricle should be extensively sampled histologically in all cases of sudden unexpected death, especially those that are exercise related.

  12. Tunneling a Pulmonary Artery Graft: A Simplified Way to Insert and Remove a Temporary Right Ventricular Assist Device.

    PubMed

    Saxena, Pankaj; Marasco, Silvana F

    2015-12-01

    Right ventricular failure can occur early or late after left ventricular assist device implantation. Support with a right ventricular assist device is needed in patients whose right ventricular failure does not respond to conservative management. The use of a temporary right ventricular assist device can enable the recovery of right ventricular function and avoid the use of a more permanent biventricular assist device, which is associated with complications and higher costs. We present our technique of instituting temporary right ventricular assist device support in patients who have undergone left ventricular assist device implantation.

  13. Predictors of right ventricular failure after left ventricular assist device implantation.

    PubMed

    Koprivanac, Marijan; Kelava, Marta; Sirić, Franjo; Cruz, Vincent B; Moazami, Nader; Mihaljević, Tomislav

    2014-12-01

    Number of left ventricular assist device (LVAD) implantations increases every year, particularly LVADs for destination therapy (DT). Right ventricular failure (RVF) has been recognized as a serious complication of LVAD implantation. Reported incidence of RVF after LVAD ranges from 6% to 44%, varying mostly due to differences in RVF definition, different types of LVADs, and differences in patient populations included in studies. RVF complicating LVAD implantation is associated with worse postoperative mortality and morbidity including worse end-organ function, longer hospital length of stay, and lower success of bridge to transplant (BTT) therapy. Importance of RVF and its predictors in a setting of LVAD implantation has been recognized early, as evidenced by abundant number of attempts to identify independent risk factors and develop RVF predictor scores with a common purpose to improve patient selection and outcomes by recognizing potential need for biventricular assist device (BiVAD) at the time of LVAD implantation. The aim of this article is to review and summarize current body of knowledge on risk factors and prediction scores of RVF after LVAD implantation. Despite abundance of studies and proposed risk scores for RVF following LVAD, certain common limitations make their implementation and clinical usefulness questionable. Regardless, value of these studies lies in providing information on potential key predictors for RVF that can be taken into account in clinical decision making. Further investigation of current predictors and existing scores as well as new studies involving larger patient populations and more sophisticated statistical prediction models are necessary. Additionally, a short description of our empirical institutional approach to management of RVF following LVAD implantation is provided. PMID:25559829

  14. Improvement of Right Ventricular Hemodynamics with Left Ventricular Endocardial Pacing during Cardiac Resynchronization Therapy

    PubMed Central

    HYDE, EOIN R.; BEHAR, JONATHAN M.; CROZIER, ANDREW; CLARIDGE, SIMON; JACKSON, TOM; SOHAL, MANAV; GILL, JASWINDER S.; O'NEILL, MARK D.; RAZAVI, REZA; RINALDI, CHRISTOPHER A.

    2016-01-01

    Background Cardiac resynchronization therapy (CRT) with biventricular epicardial (BV‐CS) or endocardial left ventricular (LV) stimulation (BV‐EN) improves LV hemodynamics. The effect of CRT on right ventricular function is less clear, particularly for BV‐EN. Our objective was to compare the simultaneous acute hemodynamic response (AHR) of the right and left ventricles (RV and LV) with BV‐CS and BV‐EN in order to determine the optimal mode of CRT delivery. Methods Nine patients with previously implanted CRT devices successfully underwent a temporary pacing study. Pressure wires measured the simultaneous AHR in both ventricles during different pacing protocols. Conventional epicardial CRT was delivered in LV‐only (LV‐CS) and BV‐CS configurations and compared with BV‐EN pacing in multiple locations using a roving decapolar catheter. Results Best BV‐EN (optimal AHR of all LV endocardial pacing sites) produced a significantly greater RV AHR compared with LV‐CS and BV‐CS pacing (P < 0.05). RV AHR had a significantly increased standard deviation compared to LV AHR (P < 0.05) with a weak correlation between RV and LV AHR (Spearman rs = −0.06). Compromised biventricular optimization, whereby RV AHR was increased at the expense of a smaller decrease in LV AHR, was achieved in 56% of cases, all with BV‐EN pacing. Conclusions BV‐EN pacing produces significant increases in both LV and RV AHR, above that achievable with conventional epicardial pacing. RV AHR cannot be used as a surrogate for optimizing LV AHR; however, compromised biventricular optimization is possible. The beneficial effect of endocardial LV pacing on RV function may have important clinical benefits beyond conventional CRT. PMID:27001004

  15. Comparative Hydrodynamics of Bacterial Polymorphism

    NASA Astrophysics Data System (ADS)

    Spagnolie, Saverio E.; Lauga, Eric

    2011-02-01

    Most bacteria swim through fluids by rotating helical flagella which can take one of 12 distinct polymorphic shapes, the most common of which is the normal form used during forward swimming runs. To shed light on the prevalence of the normal form in locomotion, we gather all available experimental measurements of the various polymorphic forms and compute their intrinsic hydrodynamic efficiencies. The normal helical form is found to be the most efficient of the 12 polymorphic forms by a significant margin—a conclusion valid for both the peritrichous and polar flagellar families, and robust to a change in the effective flagellum diameter or length. Hence, although energetic costs of locomotion are small for bacteria, fluid mechanical forces may have played a significant role in the evolution of the flagellum.

  16. Noninvasive Cardiac Screening in Young Athletes With Ventricular Arrhythmias

    PubMed Central

    Steriotis, Alexandros Klavdios; Nava, Andrea; Rigato, Ilaria; Mazzotti, Elisa; Daliento, Luciano; Thiene, Gaetano; Basso, Cristina; Corrado, Domenico; Bauce, Barbara

    2013-01-01

    The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have ventricular arrhythmias (VAs) during the preparticipation screening program for competitive sports. One hundred forty-five athletes (mean age 17 ± 5 years) were evaluated. The study protocol included electrocardiography (ECG), exercise testing, 2-dimensional and Doppler echocardiography, 24-hour Holter monitoring, signal-averaged ECG, and in selected cases contrast-enhanced cardiac magnetic resonance imaging. Results of ECG were normal in most athletes (85%). VAs were initially detected prevalently during exercise testing (85%) and in the remaining cases on ECG and Holter monitoring. Premature ventricular complexes disappeared during exercise in 56% of subjects. Premature ventricular complexes during Holter monitoring averaged 4,700 per day, predominantly monomorphic (88%), single, and/or in couplets (79%). The most important echocardiographic findings were mitral valve prolapse in 29 patients (20%), congenital heart disease in 4 (3%), and right ventricular regional kinetic abnormalities in 5 (3.5%). On cardiac magnetic resonance imaging, right ventricular regional kinetic abnormalities were detected in 9 of 30 athletes and were diagnostic of arrhythmogenic right ventricular cardiomyopathy in only 1 athlete. Overall, 30% of athletes were judged to have potentially dangerous VAs. In asymptomatic athletes with prevalently normal ECG, most VAs can be identified by adding an exercise test during preparticipation screening. In conclusion, cardiac screening with noninvasive examinations remains a fundamental tool for the identification of a possible pathologic substrate and for the characterization of electrical instability. PMID:23219000

  17. Transapical miniaturized ventricular assist device: Design and initial testing

    PubMed Central

    Slaughter, Mark S.; Giridharan, Guruprasad A.; Tamez, Dan; LaRose, Jeff; Sobieski, Mike A.; Sherwood, Leslie; Koenig, Steven C.

    2013-01-01

    Background Left ventricular assist devices are increasingly used to treat patients with advanced and otherwise refractory heart failure as bridge to transplant or destination therapy. We evaluated a new miniaturized left ventricular assist device that requires minimal surgery for implantation, potentially allowing implantation in earlier stage heart failure. Methods HeartWare (Miami Lakes, Fla) developed transapical miniaturized ventricular assist device. Acute (n = 4), 1-week (n = 2), and 30-day (n = 4) bovine model experiments evaluated hemodynamic efficacy and biocompatibility of the device, which was implanted through small left thoracotomy with single insertion at apex of left ventricle without cardiopulmonary bypass. The device outflow cannula was positioned across the aortic valve. The international normalized ratio was maintained between 2.0 and 2.5 with warfarin. Hemodynamic, echocardiographic, fluoroscopic, hematologic, and blood chemistry measurements were evaluated. Results The device was successfully implanted through the left ventricular apex in all 10 animals. The device was operated at 15,000 ± 1000 rpm (power consumption, 3.5–6.0 W). The device maintained normal end-organ perfusion with no significant hemolysis (0–30 mg/dL). There were no pump failures or device-related complications. At autopsy, no abnormalities were seen in endocardium, aortic valve leaflets, or aortic root. There was no evidence of thromboembolism or abnormalities in any peripheral end organs. Conclusions We successfully demonstrated feasibility of a novel intraventricular assist device that can be completely implanted through left ventricular apex. This transapical surgical approach eliminates needs for sternotomy, device pocket, cardiopulmonary bypass, ventricular coring, and construction of an outflow graft anastomosis. PMID:21320708

  18. Backscatter and attenuation characterization of ventricular myocardium

    NASA Astrophysics Data System (ADS)

    Gibson, Allyson Ann

    2009-12-01

    This Dissertation presents quantitative ultrasonic measurements of the myocardium in fetal hearts and adult human hearts with the goal of studying the physics of sound waves incident upon anisotropic and inhomogeneous materials. Ultrasound has been used as a clinical tool to assess heart structure and function for several decades. The clinical usefulness of this noninvasive approach has grown with our understanding of the physical mechanisms underlying the interaction of ultrasonic waves with the myocardium. In this Dissertation, integrated backscatter and attenuation analyses were performed on midgestational fetal hearts to assess potential differences in the left and right ventricular myocardium. The hearts were interrogated using a 50 MHz transducer that enabled finer spatial resolution than could be achieved at more typical clinical frequencies. Ultrasonic data analyses demonstrated different patterns and relative levels of backscatter and attenuation from the myocardium of the left ventricle and the right ventricle. Ultrasonic data of adult human hearts were acquired with a clinical imaging system and quantified by their magnitude and time delay of cyclic variation of myocardial backscatter. The results were analyzing using Bayes Classification and ROC analysis to quantify potential advantages of using a combination of two features of cyclic variation of myocardial backscatter over using only one or the other feature to distinguish between groups of subjects. When the subjects were classified based on hemoglobin A1c, the homeostasis model assessment of insulin resistance, and the ratio of triglyceride to high-density lipoprotein-cholesterol, differences in the magnitude and normalized time delay of cyclic variation of myocardial backscatter were observed. The cyclic variation results also suggested a trend toward a larger area under the ROC curve when information from magnitude and time delay of cyclic variation is combined using Bayes classification than when

  19. Oestradiol metabolism and androgen receptor genotypes are associated with right ventricular function

    PubMed Central

    Ventetuolo, Corey E.; Mitra, Nandita; Wan, Fei; Manichaikul, Ani; Barr, R. Graham; Johnson, Craig; Bluemke, David A.; Lima, Joao A.C.; Tandri, Hari; Ouyang, Pamela; Kawut, Steven M.

    2016-01-01

    Sex hormones are linked to right ventricular (RV) function, but the relationship between genetic variation in these pathways and RV function is unknown. We performed a cross-sectional study of 2761 genotyped adults without cardiovascular disease. The relationships between RV measures and single nucleotide polymorphisms (SNPs) in 10 candidate genes were assessed. Urinary oestradiol (E2) metabolites produced by cytochrome P4501B1 (CYP1B1) and serum testosterone were measured in women and men respectively. In African-American (AA) women, the CYP1B1 SNP rs162561 was associated with RV ejection fraction (RVEF), such that each copy of the A allele was associated with a 2.0% increase in RVEF. Haplotype analysis revealed associations with RVEF in AA (global p<7.2×10−6) and white (global p=0.05) women. In white subjects, higher E2 metabolite levels were associated with significantly higher RVEF. In men, androgen receptors SNPs (rs1337080; rs5918764) were significantly associated with all RV measures and modified the relationship between testosterone and RVEF. Genetic variation in E2 metabolism and androgen signalling was associated with RV morphology in a sex-specific manner. The CYP1B1 SNP identified is in tight linkage disequilibrium with SNPs associated with pulmonary hypertension and oncogenesis, suggesting these pathways may underpin sexual dimorphism in RV failure. PMID:26647441

  20. Genetic analysis of the TBX3 gene promoter in ventricular septal defects.

    PubMed

    Chen, Dongfeng; Qiao, Yanli; Meng, Haihong; Pang, Shuchao; Huang, Wenhui; Zhang, Hongyu; Yan, Bo

    2013-01-10

    Congenital heart disease (CHD) is the most common birth defect in humans. Genetic causes and underlying molecular mechanisms for CHD remain largely unknown. T-box transcription factor 3 (TBX3) plays a critical role in the developing heart in a dose-dependent manner. TBX3 represses chamber myocardial gene expression. Mutations in TBX3 gene have been associated to ulnar-mammary syndrome with multiple developmental defects, including cardiac defects. We hypothesized that the sequence variants within TBX3 gene promoter that change TBX3 levels may mediate CHD development. In this study, TBX3 gene promoter was genetically analyzed in large cohorts of patients with ventricular septal defect (VSD) (n=325) and ethnic-matched healthy controls (n=359). Seven sequence variants, including two single-nucleotide polymorphisms (g.3863 C>T and g.4095G>T), three novel deletions (g.4433_4435del, g.4672_4675del and g.4820_4821del) and two novel insertions (g.3913_3914ins and g.4735_4736ins), were identified. Five of the seven variants were identified in VSD patients and controls with similar frequencies. Two other variants were found only in controls. These variants, which were observed in high frequencies, did not modify or interrupt the critical binding site for basic transcription factors. Taken together, these results suggested that the sequence variants within the TBX3 gene promoter did not contribute to VSD etiology. PMID:23116943

  1. Irukandji syndrome, catecholamines, and mid-ventricular stress cardiomyopathy.

    PubMed

    Tiong, Keith

    2009-03-01

    We present here the first reported case of mid-ventricular stress cardiomyopathy secondary to 'Irukandji syndrome', following envenomisation from a jellyfish. Carukia barnesi is a cubozoan or box jellyfish found in Far North Queensland, Australia prevalent during the warmer months of the year. It has been associated with 'Irukandji syndrome' as characterized by a sympathetic overdrive secondary to an excess of endogenous catecholamines release. There have been previous cases of sudden onset of left ventricular dysfunction and jellyfish. The author believes that this case is important because it highlights the possible association between the sudden release in catecholamines and stress cardiomyopathy. PMID:18801721

  2. Mechanisms of Ventricular Arrhythmias: From Molecular Fluctuations to Electrical Turbulence

    PubMed Central

    Qu, Zhilin; Weiss, James N.

    2015-01-01

    Ventricular arrhythmias have complex causes and mechanisms. Despite extensive investigation involving many clinical, experimental, and computational studies, effective biological therapeutics are still very limited. In this article, we review our current understanding of the mechanisms of ventricular arrhythmias by summarizing the state of knowledge spanning from the molecular scale to electrical wave behavior at the tissue and organ scales and how the complex nonlinear interactions integrate into the dynamics of arrhythmias in the heart. We discuss the challenges that we face in synthesizing these dynamics to develop safe and effective novel therapeutic approaches. PMID:25340965

  3. Determination of left ventricular mass through SPECT imaging

    NASA Astrophysics Data System (ADS)

    Zárate-Morales, A.; Rodríguez-Villafuerte, M.; Martínez-Rodríguez, F.; Arévila-Ceballos, N.

    1998-08-01

    An edge detection algorithm has been applied to estimate left ventricular (LV) mass from single photon emission computed tomography (SPECT) thallium-201 images. The algorithm was validated using SPECT images of a phantom. The algorithm was applied to 20 patient studies from the Hospital de Cardiologia, Centro Médico Nacional Siglo XXI. Left ventricular masses derived from the stress and redistribution studies were highly correlated (r=0.96). The average LV masses obtained were 162±37 g and 169±34 g in the redistribution and stress studies, respectively.

  4. Iron deficiency and hemolytic anemia reversed by ventricular septal myectomy.

    PubMed

    Thotakura, Sudhir; Costa, Steven M; Cable, Christian

    2015-10-01

    Hemolytic anemia has been reported to occur in the setting of aortic stenosis and prosthetic heart valves, but much more rarely in association with obstructive hypertrophic cardiomyopathy (HC). Of the few descriptions of hemolytic anemia secondary to HC, all but one case involved bacterial endocarditis contributing to left ventricular outflow tract obstruction. We present the case of a 67-year-old man with recurrent hemolytic anemia and HC, without infective endocarditis. Attempts at iron repletion and augmentation of beta-blocker therapy proved his anemia to be refractory to medical management. Ventricular septal myectomy led to the resolution of hemolysis, anemia, and its coexisting symptoms.

  5. Pathological Ventricular Remodeling: Mechanisms: Part 1 of 2

    PubMed Central

    Xie, Min; Burchfield, Jana S.; Hill, Joseph A.

    2013-01-01

    Despite declines in heart failure morbidity and mortality with current therapies, re-hospitalization rates remain distressingly high, impacting substantially on individuals, society, and the economy. As a result, the need for new therapeutic advances and novel medical devices is urgent. Disease-related left ventricular remodeling is a complex process involving cardiac myocyte growth and death, vascular rarefaction, fibrosis, inflammation, and electrophysiological remodeling. As these events are highly inter-related, targeting one single molecule or process may not be sufficient. Here, we review molecular and cellular mechanisms governing pathological ventricular remodeling. PMID:23877061

  6. Limitations to Chronic Right Ventricular Assist Device Support.

    PubMed

    Karimov, Jamshid H; Sunagawa, Gengo; Horvath, David; Fukamachi, Kiyotaka; Starling, Randall C; Moazami, Nader

    2016-08-01

    Failure of the right ventricle represents a significant clinical problem and may have different causes, with rates varying between 5% and 50% in patients supported by a left ventricular assist device (LVAD). However, treatment options and device development for right ventricular failure (RVF) have significantly lagged behind those for LVADs. Newer technologies designed or adapted for RV support are needed to provide adequate long-term circulatory support. In this review, we discuss (1) the significance of RVF and its physiologic implications, (2) device constraints affecting treatment options for RVF, and (3) implantable VADs potentially available for RV support. PMID:27106620

  7. A global perspective of arrhythmogenic right ventricular cardiomyopathy

    PubMed Central

    Elmaghawry, Mohamed; Alhashemi, Mohammed; Zorzi, Alessandro; Yacoub, Magdi H

    2012-01-01

    Abstract: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive inherited heart disease characterized by ventricular arrhythmias and sudden cardiac death especially in the young. ARVC has been traditionally associated with the Mediterranean basin, as many seminal studies on the disease have originated from research groups of this region. Today, however, numerous ARVC registries from all over the world emphasize that the disease does not have a specific racial or geographical predilection. This work provides a review on the global perspective of ARVC. PMID:24688993

  8. Adherence to thresholds: overdiagnosis of left ventricular noncompaction cardiomyopathy.

    PubMed

    Kini, Vinay; Ferrari, Victor A; Han, Yuchi; Jha, Saurabh

    2015-08-01

    Thresholds derived from quantification in imaging are increasingly used to define disease. This derivation is not an exact science. When one uses a threshold to define a disease, one does not clearly demarcate disease from normality because the threshold includes overlapping spectra of mild disease and normality. Thus, use of the threshold will mislabel normal individuals with disease. In this perspective, we will describe how the threshold has been derived for left ventricular noncompaction cardiomyopathy, the statistical biases in the design of studies used to derive the threshold, and the dangers of overdiagnosis when the threshold is used to rule out left ventricular noncompaction cardiomyopathy.

  9. Ventricular assist devices: preparing for catastrophic environmental events.

    PubMed

    Bartell, Lisa A

    2005-09-01

    In the summer of 2004, Florida experienced 4 major hurricanes in a matter of weeks. These hurricanes left many Floridians without power and passable roads, interrupted communications, and destroyed some homes. During this time, Tampa General Hospital had 1 patient living at home with an implanted ventricular assist device. The patient had been discharged home only 2 weeks before hurricane Frances hit hard. Although the patient was able to stay at home and experienced no major problems with the device, there were several situations that taught us many lessons about caring for patients with ventricular assist devices during environmental catastrophic events.

  10. Ion beam sputter-etched ventricular catheter for hydrocephalus shunt

    NASA Technical Reports Server (NTRS)

    Banks, B. A. (Inventor)

    1983-01-01

    A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

  11. Androgenic anabolic steroids also impair right ventricular function.

    PubMed

    Kasikcioglu, Erdem; Oflaz, Huseyin; Umman, Berrin; Bugra, Zehra

    2009-05-01

    Chronic anabolic steroid use suppresses left ventricular functions. However, there is no information regarding the chronic effects of anabolic steroids on right ventricular function which also plays a key role in global cardiac function. The main objective of the present study was to investigate the effects of androgenic anabolic steroids usage among athletes on remodeling the right part of the heart. Androgenic-anabolic steroids-using bodybuilders had smaller diastolic velocities of both ventricles than drug-free bodybuilders and sedentary counterparts. This study shows that androgenic anabolic steroids-using bodybuilders exhibited depressed diastolic functions of both ventricles.

  12. 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

  13. Overview of left ventricular outpouchings on cardiac magnetic resonance imaging

    PubMed Central

    Kumar, Sanjeev

    2015-01-01

    Left ventricular outpouchings commonly include aneurysm, pseudoaneurysm, and diverticulum and are now being increasingly detected on imaging. Distinction between these entities is of prime importance to guide proper management as outcomes for these entities differ substantially. Chest radiograph is usually nonspecific in their diagnosis. Echocardiography, multi-detector computed tomography evaluation and angiography are helpful in the diagnosis with their inherit limitations. Cardiac magnetic resonance imaging (MRI) is emerging as a very useful tool that allows simultaneous anatomical and functional evaluation along with tissue characterization, which has diagnostic, theraputic and prognostic implications. This article gives an overview of left ventricular outpouchings with special emphasis on their differentiation using cardiac MRI. PMID:26675616

  14. Right ventricular noncompaction in a neonate with complex congenital heart disease.

    PubMed

    Alehan, Dursun; Dogan, Omer Faruk

    2005-08-01

    Ventricular noncompaction is a rare unclassified cardiomyopathy occurring because of arrest of the normal intrauterine compaction of the loose luminal component of the ventricular myocardium. There is limited data regarding its diagnosis and outcome in children. It is recognised, however, that right ventricular involvement is extremely rare. We report a case in which only the right ventricular myocardium was noncompacted, a situation which led to heart failure soon after birth.

  15. Adjuvant therapy with methylene blue in the treatment of right ventricular failure after pulmonary embolectomy.

    PubMed

    Raikhelkar, Jayashree K; Milla, Federico; Darrow, Bruce; Scurlock, Corey

    2011-04-01

    Severe pulmonary embolism often leads to right ventricular failure after surgical embolectomy secondary to ischaemia reperfusion injury and acute lung injury (ALI). Acute right ventricular dysfunction is traditionally treated with inotropes and vasopressors to maintain cardiac output and coronary perfusion as well as selective pulmonary vasodilators to provide right ventricular afterload reduction. We report the first case of utilisation of methylene (MB) in a patient with acute right ventricular failure and vasoplegic shock after surgical pulmonary embolectomy. PMID:20952252

  16. Crystal Polymorphs of Barbital: News about a Classic Polymorphic System

    PubMed Central

    2013-01-01

    Barbital is a hypnotic agent that has been intensely studied for many decades. The aim of this work was to establish a clear and comprehensible picture of its polymorphic system. Four of the six known solid forms of barbital (denoted I0, III, IV, and V) were characterized by various analytical techniques, and the thermodynamic relationships between the polymorph phases were established. The obtained data permitted the construction of the first semischematic energy/temperature diagram for the barbital system. The modifications I0, III, and V are enantiotropically related to one another. Polymorph IV is enantiotropically related to V and monotropically related to the other two forms. The transition points for the pairs I0/III, I0/V, and III/IV lie below 20 °C, and the transition point for IV/V is above 20 °C. At room temperature, the order of thermodynamic stability is I0 > III > V > IV. The metastable modification III is present in commercial samples and has a high kinetic stability. The solid-state NMR spectra provide information on aspects of crystallography (viz., the asymmetric units and the nature of hydrogen bonding). The known correlation between specific N–H···O=C hydrogen bonding motifs of barbiturates and certain IR characteristics was used to predict the H-bonded pattern of polymorph IV. PMID:24283960

  17. Reversal of premature ventricular complex-induced cardiomyopathy following successful radiofrequency catheter ablation.

    PubMed

    Efremidis, Michalis; Letsas, Konstantinos P; Sideris, Antonios; Kardaras, Fotios

    2008-06-01

    Premature ventricular complex (PVC)-induced cardiomyopathy is an underappreciated cause of left-ventricular (LV) dysfunction. The present report describes the case of an elderly man with a very high burden of monomorphic PVCs and LV dysfunction. Elimination of the left ventricular focus following radiofrequency catheter ablation resulted in reversal of cardiomyopathy.

  18. Reversal of ventricular premature beat induced cardiomyopathy by radiofrequency catheter ablation.

    PubMed

    Blaauw, Y; Pison, L; van Opstal, J M; Dennert, R M; Heesen, W F; Crijns, H J G M

    2010-10-01

    Frequent monomorphic ventricular premature beats (VPBs) may lead to left ventricular dysfunction. We describe two patients with frequent monomorphic VPBs and dilated cardiomyopathy in whom left ventricular function normalised after elimination of the VPBs by radiofrequency catheter ablation. The recent literature on this topic is summarised and potential candidates for catheter ablation are discussed. (Neth Heart J 2010;18:493-8.).

  19. Short Communication: Conformal Therapy for Peri-Ventricular Brain Tumors: Is Target Volume Deformation an Issue?

    SciTech Connect

    Bauman, Glenn Woodford, Curtis; Yartsev, Slav

    2008-04-01

    Physiologic variations in ventricular volumes could have important implications for treating patients with peri-ventricular brain tumors, yet no data exist in the literature addressing this issue. Daily megavoltage computed tomography (CT) scans in a patient with neurocytoma receiving fractionated radiation revealed minimal changes, suggesting that margins accounting for ventricular deformation are not necessary.

  20. Ventricular septal defect and double-chambered right ventricle in an alpaca.

    PubMed

    Poser, Helen; Dalla Pria, Angela; De Benedictis, Giulia M; Stelletta, Calogero; Berlanda, Michele; Guglielmini, Carlo

    2015-03-01

    A 20-month-old male alpaca was referred for evaluation of a cardiac murmur evident since birth. Echocardiography identified a ventricular septal defect (VSD) and a fibro-muscular band causing a stenosis of the right ventricular outflow tract. Right ventricular catheterization and selective angiography confirmed the diagnosis of VSD and double-chambered right ventricle with bidirectional shunting.

  1. Parasympathetic neurons in the cranial medial ventricular fat pad on the dog heart selectively decrease ventricular contractility.

    PubMed

    Dickerson, L W; Rodak, D J; Fleming, T J; Gatti, P J; Massari, V J; McKenzie, J C; Gillis, R A

    1998-05-28

    We hypothesized that selective control of ventricular contractility might be mediated by postganglionic parasympathetic neurons in the cranial medial ventricular (CMV) ganglion plexus located in a fat pad at the base of the aorta. Sinus rate, atrioventricular (AV) conduction (ventricular rate during atrial pacing), and left ventricular contractile force (LV dP/dt during right ventricular pacing) were measured in eight chloralose-anesthetized dogs both before and during bilateral cervical vagus stimulation (20-30 V, 0.5 ms pulses, 15-20 Hz). Seven of these dogs were tested under beta-adrenergic blockade (propranolol, 0.8 mg kg(-1) i.v.). Control responses included sinus node bradycardia or arrest during spontaneous rhythm, high grade AV block or complete heart block, and a 30% decrease in contractility from 2118 +/- 186 to 1526 +/- 187 mm Hg s(-1) (P < 0.05). Next, the ganglionic blocker trimethaphan (0.3-1.0 ml of a 50 microg ml(-1) solution) was injected into the CMV fat pad. Then vagal stimulation was repeated, which now produced a relatively small 5% (N.S., P > 0.05) decrease in contractility but still elicited the same degree of sinus bradycardia and AV block (N = 8, P < 0.05). Five dogs were re-tested 3 h after trimethaphan fat pad injection, at which time blockade of vagally-induced negative inotropy was partially reversed, as vagal stimulation decreased LV dP/dt by 19%. The same dose of trimethaphan given either locally into other fat pads (PVFP or IVC-ILA) or systemically (i.v.) had no effect on vagally-induced negative inotropy. Thus, parasympathetic ganglia located in the CMV fat pad mediated a decrease in ventricular contractility during vagal stimulation. Blockade of the CMV fat pad had no effect on vagally-mediated slowing of sinus rate or AV conduction.

  2. 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

  3. Polymorphism in pleistocene land snails.

    PubMed

    Owen, D F

    1966-04-01

    Under suitable conditions the colors and patterns of the shells of land snails may be preserved for thousands of years. In a late Pleistocene population of Limicolaria martensiana all the major color forms that occur in modern living snails may be distinguished, and the basic polymorphism is at least 8,000 to 10,000 year old. PMID:17830234

  4. The feasibility and efficacy of right ventricular assistance without thoracotomy.

    PubMed

    Yano, M; Matsuo, K; Hatane, T; Araki, K; Onitsuka, T; Shibata, K; Koga, Y

    1993-01-01

    Mechanical right ventricular assistance has never been percutaneously instituted. We invented a new method for administering right ventricular assistance without thoracotomy (RAWT) and evaluated its effects in acute experiments using dogs. To institute RAWT, an outflow cannula was inserted into the pulmonary artery from the femoral vein, and an inflow cannula was inserted into the right atrium from the right jugular vein. A Swan-Ganz catheter inserted into the outflow cannula led it to the pulmonary artery under blood pressure monitoring only. A Sarns' centrifugal pump was used as a blood pump. We applied this system to biventricular failed hearts supported by a left ventricular assist device. We could increase cardiac output from 53.3 +/- 31.8 to 77.8 +/- 31.7 ml/min/kg, and mean aortic pressure from 43.5 +/- 12.3 to 57.5 +/- 11.2 mm Hg with RAWT. The right ventricular unloading effect of RAWT was not disturbed by regurgitation through the pulmonary or tricuspid valve.

  5. Perventricular closure of a perimembranous ventricular septal defect.

    PubMed

    Schreiber, Christian; Nöbauer, Christian; Zhang, Fengwei; Zhuang, Zhongyun

    2013-01-01

    In recent years, perventricular ventricular septal defect device closure without cardiopulmonary bypass has gained increasing acceptance in China. Under transoesophageal echocardiography guidance, muscular, perimembranous and even doubly committed defects are closed. We performed the first application of this technique outside of China and explain step-by-step the hybrid procedure.

  6. Isolated right ventricular failure in hyperthyroidism: a clinical dilemma

    PubMed Central

    McDonough, Ryan J.; Moul, Marvin S.; Beckman, Darrick; Slim, Ahmad M.

    2011-01-01

    We present a unique case of a 42-year-old gentleman with newly diagnosed Graves’ disease and isolated right ventricular failure. Extensive evaluation to include echocardiogram and cardiac catheterization were negative for significant pulmonary hypertension or coronary artery disease as potential etiologies. Hyperthyroid induced vasospasm is a rare but reported clinical entity that serves to be a clinical and diagnostic dilemma. PMID:22049310

  7. Advances in Modeling Ventricular Arrhythmias: from Mechanisms to the Clinic

    PubMed Central

    Trayanova, Natalia A.; Boyle, Patrick M.

    2014-01-01

    Modern cardiovascular research has increasingly recognized that heart models and simulation can help interpret an array of experimental data and dissect important mechanisms and interrelationships, with developments rooted in the iterative interaction between modeling and experimentation. This article reviews the progress made in simulating cardiac electrical behavior at the level of the organ and, specifically, in the development of models of ventricular arrhythmias and fibrillation, as well as their termination (defibrillation). The ability to construct multi-scale models of ventricular arrhythmias, representing integrative behavior from the molecule to the entire organ, has enabled mechanistic inquiry into the dynamics of ventricular arrhythmias in the diseased myocardium, in understanding drug-induced pro-arrhythmia, and in the development of new modalities for defibrillation, to name a few. In this article we also review the initial use of ventricular models of arrhythmia in personalized diagnosis, treatment planning, and prevention of sudden cardiac death. Implementing individualized cardiac simulations at the patient bedside is poised to become one of the most thrilling examples of computational science and engineering approaches in translational medicine. PMID:24375958

  8. Left ventricular function impairment in pregnancy-induced hypertension.

    PubMed

    Vázquez Blanco, M; Roisinblit, J; Grosso, O; Rodriguez, G; Robert, S; Berensztein, C S; Vega, H R; Lerman, J

    2001-03-01

    The changes induced by transient hypertension on cardiac structure and function are unclear. Pregnancy-induced hypertension offers a natural and spontaneous model of this condition. To assess the potential of echocardiographic Doppler to unmask left ventricular function impairment, we studied 28 women aged 26.4 +/- 7.2 years with pregnancy-induced hypertension defined as blood pressure higher than 140/90 mm Hg in the third trimester of pregnancy without a history of hypertension. Twenty normal pregnant women, aged 27.5 +/- 6.4 years, were the controls. Left ventricular diastolic diameter, fractional shortening, E velocity, A velocity, E/A ratio, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), ejection time (ET), and the combined index of myocardial performance (Tei index = IRT + ICT/ET), were calculated by echocardiography Doppler 2 to 4 days postpartum. There were statistically significant differences between groups in the following parameters: E/A ratio: 1.3 +/- 0.3 in pregnancy-induced hypertension v 1.5 +/- 0.3 in normal pregnant women (P < .05), IRT: 104 +/- 14 msec v 84 +/- 7 msec (P < .000), and the Tei index: 0.51 +/- 0.15 v 0.35 +/- 0.04 (P < .00), respectively. According to this data pregnancy-induced hypertension evaluated 2 to 4 days after delivery showed left ventricular dysfunction, mainly diastolic. The IRT and the Tei index are the most useful echocardiographic parameters to unmask left ventricular dysfunction in pregnancy-induced hypertension.

  9. Cardiac cryosurgery: regional myocardial blood flow of ventricular cryolesions

    SciTech Connect

    Holman, W.L.; Ikeshita, M.; Lease, J.G.; Smith, P.K.; Ungerleider, R.M.; Cox, J.L.

    1986-11-01

    Cryosurgery is one of three methods introduced recently for the treatment of ventricular tachyarrhythmias. Cryothermic exposure ablates arrhythmogenic ventricular myocardium, and produces a dense fibrous scar with a sharp border to histologically normal tissue. Myocardial blood flow in the region of the cryolesion, however, has not been quantitated. The purpose of this study was to measure regional blood flow within and around the cryolesion in an attempt to identify ischemic zones that might become arrhythmogenic. Left ventricular cryolesions were created in eleven adult dogs. Two weeks later, the animals underwent radioactive tracer microsphere injection for quantitation of regional myocardial blood flow. The fibrotic cryolesion demonstrated a significantly depressed blood flow (0.44 +/- 0.07 ml/min/g) compared to blood flow in control tissue (1.36 +/- 0.12 ml/min/g) (P less than 0.001). A 1-mm strip of myocardium immediately adjacent to the cryolesion, as well as other myocardium surrounding and subjacent to the cryolesion, did not show a significant decrease in regional blood flow. The border between the fibrotic cryolesion and the surrounding myocardium is, therefore, sharply defined not only in terms of histology but also in regards to regional blood flow. These data lend further support to the safe clinical use of cryothermia in the treatment of refractory ventricular tachycardia.

  10. Laparoscopic repair of diaphragmatic hernia after left ventricular assist device.

    PubMed

    Farma, Jeffrey; Leeser, David; Furukawa, Satoshi; Dempsey, Daniel T

    2003-06-01

    This case report describes a patient with a symptomatic diaphragmatic hernia that developed after orthotopic heart transplantation and explantation of a left ventricular assist device. The hernia was repaired laparoscopically, and at 6-month follow-up, she is without evidence of recurrence.

  11. Towards the development of a pediatric ventricular assist device.

    PubMed

    Borovetz, Harvey S; Badylak, Stephen; Boston, J Robert; Johnson, Carl; Kormos, Robert; Kameneva, Marina V; Simaan, Marwan; Snyder, Trevor A; Tsukui, Hiro; Wagner, William R; Woolley, Joshua; Antaki, James; Diao, Chenguang; Vandenberghe, Stijn; Keller, Bradley; Morell, Victor; Wearden, Peter; Webber, Steven; Gardiner, Jeff; Li, Chung M; Paden, Dave; Paden, Bradley; Snyder, Shaun; Wu, Jingchun; Bearnson, Gill; Hawkins, John A; Jacobs, Gordon; Kirk, John; Khanwilkar, Pratap; Kouretas, Peter C; Long, James; Shaddy, R E

    2006-01-01

    The very limited options available to treat ventricular failure in children with congenital and acquired heart diseases have motivated the development of a pediatric ventricular assist device at the University of Pittsburgh (UoP) and University of Pittsburgh Medical Center (UPMC). Our effort involves a consortium consisting of UoP, Children's Hospital of Pittsburgh (CHP), Carnegie Mellon University, World Heart Corporation, and LaunchPoint Technologies, Inc. The overall aim of our program is to develop a highly reliable, biocompatible ventricular assist device (VAD) for chronic support (6 months) of the unique and high-risk population of children between 3 and 15 kg (patients from birth to 2 years of age). The innovative pediatric ventricular assist device we are developing is based on a miniature mixed flow turbodynamic pump featuring magnetic levitation, to assure minimal blood trauma and risk of thrombosis. This review article discusses the limitations of current pediatric cardiac assist treatment options and the work to date by our consortium toward the development of a pediatric VAD.

  12. Normalised radionuclide measures of left ventricular diastolic function.

    PubMed

    Lee, K J; Southee, A E; Bautovich, G J; Freedman, B; McLaughlin, A F; Rossleigh, M A; Hutton, B F; Morris, J G

    1989-01-01

    Abnormal left ventricular diastolic function is being increasingly recognised in patients with clinical heart failure and normal systolic function. A simple routine radionuclide measure of diastolic function would therefore be useful. To establish this, the relationship of peak diastolic filling rate (normalized for either end diastolic volume, stroke volume, or peak systolic emptying rate), and heart rate, age, and left ventricular ejection fraction was studied in 64 subjects with normal cardiovascular systems using routine gated heart pool studies. The peak filling rate, when normalized to end diastolic volume, correlated significantly with heart rate, age and left ventricular ejection fraction, whereas normalization to stroke volume correlated significantly to heart rate and age but not to left ventricular ejection fraction. Peak filling rate normalized for peak systolic emptying rate correlated with age only. Multiple regression equations were determined for each of the normalized peak filling rates in order to establish normal ranges for each parameter. When using peak filling rate normalized for end diastolic volume or stroke volume, appropriate allowance must be made for heart rate, age and ejection fraction. Peak filling rate normalized to peak ejection rate is a heart rate independent parameter which allows the performance of the patient's ventricle in diastole to be compared with its systolic function. It may be used in patients with normal systolic function to serially follow diastolic function or if age corrected, to screen for diastolic dysfunction. PMID:2540982

  13. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular bypass (assist) device. 870.3545 Section 870.3545 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545...

  14. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ventricular bypass (assist) device. 870.3545 Section 870.3545 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545...

  15. Electronic circuit detects left ventricular ejection events in cardiovascular system

    NASA Technical Reports Server (NTRS)

    Gebben, V. D.; Webb, J. A., Jr.

    1972-01-01

    Electronic circuit processes arterial blood pressure waveform to produce discrete signals that coincide with beginning and end of left ventricular ejection. Output signals provide timing signals for computers that monitor cardiovascular systems. Circuit operates reliably for heart rates between 50 and 200 beats per minute.

  16. Calcium-sensing receptor induces rat neonatal ventricular cardiomyocyte apoptosis

    SciTech Connect

    Sun Yihua; Liu Meina; Li Hong; Shi Sa; Zhao Yajun; Wang Rui; Xu Changqing . E-mail: syh200415@yahoo.com.cn

    2006-12-01

    The calcium-sensing receptor (CaSR) exists in many tissues, and its expression has been identified in rat cardiac tissue. However, Physiological importance and pathophysiological involvement of CaSR in homeostatic regulation of cardiac function are unclear. To investigate the relation of CaSR and apoptosis in cardiomyocytes, we examined the role of the CaSR activator gadolinium chloride (GdCl{sub 3}) in rat neonatal ventricular cardiomyocytes. Expression of the CaSR protein was observed by Western blot. The apoptotic ratio of rat neonatal ventricular cardiomyocytes was measured with flow cytometry and immunofluorescence techniques. A laser scan confocal microscope was used to detect the intracellular concentration of calcium ([Ca{sup 2+}]{sub i}) in rat neonatal ventricular cardiomyocytes using the acetoxymethyl ester of fluo-3 (fluo-3/(AM)) as a fluorescent dye. The results showed that GdCl{sub 3} increased the phosphorylation of extracellular signal-regulated protein kinase (ERK), c-Jun NH{sub 2}-terminal protein kinases (JNK), and p38. GdCl{sub 3} also activated caspase 9 and increased apoptosis in myocyte by increasing [Ca{sup 2+}]{sub i}. In conclusion, these results suggest that CaSR promotes cardiomyocyte apoptosis in rat neonatal ventricular cardiomyocytes through activation of mitogen-activated protein kinases and caspase 9 signaling pathways.

  17. Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology

    PubMed Central

    Krishnamoorthi, Shankarjee; Perotti, Luigi E.; Borgstrom, Nils P.; Ajijola, Olujimi A.; Frid, Anna; Ponnaluri, Aditya V.; Weiss, James N.; Qu, Zhilin; Klug, William S.; Ennis, Daniel B.; Garfinkel, Alan

    2014-01-01

    We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transmural and apex-to-base gradients of action potential characteristics. We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time. We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential. These include producing a physiologically accurate ECG, a correct ventricular activation sequence, and the inducibility of ventricular fibrillation. Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations. PMID:25493967

  18. Intramyocardial activation in early ventricular arrhythmias following coronary artery ligation.

    PubMed

    Kaplinsky, E; Ogawa, S; Kmetzo, J; Balke, C W; Dreifus, L S

    1980-01-01

    Subendocardial, subepicardial and intramyocardial activation in the ischemic zone was investigated in 20 anesthetized open chest dogs 0-30 minutes after the ligation of the left anterior descending coronary artery. Single and composite electrograms and lead 2 of the ECG were recorded. Coronary artery ligation produced marked delay, fragmentation, and reduction in amplitude in the electrical activity of the subepicardial and intramyocardial muscle layers. The activation remained synchronous in the subendocardial muscle layers. Extension of electrical activity in the ischemic subepicardium and intramyocardium beyond the T wave of the surface ECG preceded the onset of immediate ventricular arrhythmias (IVA) during the initial ten minute period after coronary artery ligation. However, a second surge of delayed ventricular arrhythmias (DVA), 10-30 minutes after ligation, was not associated with the appearance of diastolic electrical activity in any of the subepicardial or myocardial layers. It appears that subepicardial as well as intramyocardial reentry could play an important role in the genesis of the immediate ventricular arrhythmias (1-10 minutes after ligation). In contrast, no obvious reentrant activity as evidenced by delayed and fragmented electrical activity could be observed in the electrogram from any of the myocardial electrical activity could be observed in the electrogram from any of the myocardial layers with the appearance of delayed ventricular ectopic activity 10-30 minutes after ligation.

  19. Haemolysis after Amplatzer device closure of ventricular septal defect

    PubMed Central

    Mulvaney, S; Grech, V

    2007-01-01

    Over the last few years, a vast variety of devices have been developed to close various septal defects through the transcatheter route. Haemolysis has been documented after Amplatzer device closure of patent ductus arteriousus, atrial septal defect, and ventricular septal defect. We report one patient with self-limiting haemolysis after implantation of an Amplatzer perimembranous VSD device. PMID:22368673

  20. 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

  1. Novel Micropatterned Cardiac Cell Cultures with Realistic Ventricular Microstructure

    PubMed Central

    Badie, Nima; Bursac, Nenad

    2009-01-01

    Systematic studies of cardiac structure-function relationships to date have been hindered by the intrinsic complexity and variability of in vivo and ex vivo model systems. Thus, we set out to develop a reproducible cell culture system that can accurately replicate the realistic microstructure of native cardiac tissues. Using cell micropatterning techniques, we aligned cultured cardiomyocytes at micro- and macroscopic spatial scales to follow local directions of cardiac fibers in murine ventricular cross sections, as measured by high-resolution diffusion tensor magnetic resonance imaging. To elucidate the roles of ventricular tissue microstructure in macroscopic impulse conduction, we optically mapped membrane potentials in micropatterned cardiac cultures with realistic tissue boundaries and natural cell orientation, cardiac cultures with realistic tissue boundaries but random cell orientation, and standard isotropic monolayers. At 2 Hz pacing, both microscopic changes in cell orientation and ventricular tissue boundaries independently and synergistically increased the spatial dispersion of conduction velocity, but not the action potential duration. The realistic variations in intramural microstructure created unique spatial signatures in micro- and macroscopic impulse propagation within ventricular cross-section cultures. This novel in vitro model system is expected to help bridge the existing gap between experimental structure-function studies in standard cardiac monolayers and intact heart tissues. PMID:19413993

  2. Novel Role for Vinculin in Ventricular Myocyte Mechanics and Dysfunction

    PubMed Central

    Tangney, Jared R.; Chuang, Joyce S.; Janssen, Matthew S.; Krishnamurthy, Adarsh; Liao, Peter; Hoshijima, Masahiko; Wu, Xin; Meininger, Gerald A.; Muthuchamy, Mariappan; Zemljic-Harpf, Alice; Ross, Robert S.; Frank, Lawrence R.; McCulloch, Andrew D.; Omens, Jeffrey H.

    2013-01-01

    Vinculin (Vcl) plays a key structural role in ventricular myocytes that, when disrupted, can lead to contractile dysfunction and dilated cardiomyopathy. To investigate the role of Vcl in myocyte and myocardial function, cardiomyocyte-specific Vcl knockout mice (cVclKO) and littermate control wild-type mice were studied with transmission electron microscopy (TEM) and in vivo magnetic resonance imaging (MRI) tagging before the onset of global ventricular dysfunction. MRI revealed significantly decreased systolic strains transverse to the myofiber axis in vivo, but no changes along the muscle fibers or in fiber tension in papillary muscles from heterozygous global Vcl null mice. Myofilament lattice spacing from TEM was significantly greater in cVclKO versus wild-type hearts fixed in the unloaded state. AFM in Vcl heterozygous null mouse myocytes showed a significant decrease in membrane cortical stiffness. A multiscale computational model of ventricular mechanics incorporating cross-bridge geometry and lattice mechanics showed that increased transverse systolic stiffness due to increased lattice spacing may explain the systolic wall strains associated with Vcl deficiency, before the onset of ventricular dysfunction. Loss of cardiac myocyte Vcl may decrease systolic transverse strains in vivo by decreasing membrane cortical tension, which decreases transverse compression of the lattice thereby increasing interfilament spacing and stress transverse to the myofibers. PMID:23561539

  3. Sustained Ventricular Tachycardia and Cardiogenic Shock due to Scorpion Envenomation.

    PubMed

    Miranda, Carlos Henrique; Maio, Karina Tozatto; Moreira, Henrique Turin; Moraes, Marcos; Custodio, Viviane Imaculada do Carmo; Pazin-Filho, Antonio; Cupo, Palmira

    2014-01-01

    We describe a case of severe scorpion envenomation in an adult patient, with the presence of very rapid sustained ventricular tachycardia followed by cardiogenic shock, which was reversed by scorpion antivenom administration. Scorpion venom causes cardiac changes that can lead to an environment favoring arrhythmogenesis. PMID:24715906

  4. Absence of left ventricular hypertrophy in elite college basketball players.

    PubMed

    Wolfe, L A; Martin, R P; Seip, R L

    1985-09-01

    Left ventricular dimensions of 11 successful male college basketball players engaged in pre-season conditioning (mean age, 20.3 years) and 13 tall healthy male controls (mean age, 21.6 years) were studied by echocardiography. Left ventricular internal dimension (LVIDd, mm), posterior wall thickness (PWT, mm), septal thickness (ST, mm), and calculated left ventricular mass (LV mass, g) in the athletes were within or only slightly in excess of echocardiographic normal limits and mean values were not significantly different from the control group. LVIDd (mm/m2 body surface area) was significantly lower in the athletes. However, five guard-type players displayed significantly greater mean values for PWT and LV mass compared to six taller forwards/centers with linear body builds. It was concluded that left ventricular hypertrophy is not a common characteristic of college basketball players. It was hypothesized that cardiac dimensions of young men may vary independently of gross body size in relation to somatotype or other anthropometric variables.

  5. Interleukin gene polymorphisms in pneumoconiosis.

    PubMed

    Helmig, Simone; Grossmann, Martin; Wübbeling, Jelena; Schneider, Joachim

    2012-08-01

    Inhaled asbestos fibres are known to cause inflammation processes with the result of lung or pleural fibrosis and malignancies. Interleukins (IL), such as IL-1β, IL-6 and IL-10, have various functions in the regulation of the inflammatory response and in proliferative processes after inhalation of silica dust and can, therefore, influence the pathogenesis of asbestos-induced fibrosis and carcinogenesis. Polymorphisms within these genes may be associated with susceptibility to silica and asbestos-induced lung diseases. Thus, IL-1β, IL-6 and IL-10 polymorphisms were examined to determine an association with asbestos or silica-induced fibrosis or malignancies. Association studies were performed in 1180 individuals, using control subjects (n=177), fibrosis patients (n=605), lung cancer (LC) patients (n=364) and malignant mesothelioma (MM) patients (n=34). IL-1β (C-511T; C+3954T), IL-6 (G-174C) as well as IL-10 (G-1082A) polymorphisms were investigated. Compared to a healthy (control) group, a higher risk was seen for malignant mesothelioma patients in all investigated polymorphisms. The IL-6 -174C allele showed a tendency towards a higher risk for fibrosis or asbestos-induced lung cancer (ORasbestosis, 1.338; 95% CI, 0.71-2.53; ORsilicosis, 1.226; 95% CI, 0.54-2.81; ORfibrosis other aetiology, 1.313; 95% CI, 0.58-2.98 and ORLC asbestos, 2.112; 95% CI, 0.75-5.92). The IL-10 -1082A carrier seemed to be at higher risk for silicosis (ORsilicosis, 2.064; 95% CI, 0.78-5.49) but not for asbestosis. In summary, this study did not reveal sufficient evidence for a significant association of the investigated interleukin polymorphisms with asbestos or silica-induced diseases in the population studied.

  6. Characterization of polymorphic ampicillin forms.

    PubMed

    Baraldi, C; Tinti, A; Ottani, S; Gamberini, M C

    2014-11-01

    In this work polymorphs of α-aminobenzylpenicillin (ampicillin), a β-lactamic antibiotic, were prepared and investigated by several experimental and theoretical methods. Amorphous monohydrate and three crystalline forms, the trihydrate, the crystal form I and the crystal form II, were investigated by FT-IR and micro-Raman. Also data obtained by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and hot-stage Raman spectroscopy are reported. Finally, quantum mechanical calculations were performed by density functional theory (DFT) to assist the assignment of spectroscopic experimental bands. For the first time, the ampicillin molecule in its zwitterionic form was studied at the B3LYP/aug-cc-pVDZ level and the corresponding theoretical vibrational spectra were computed. In fact, ampicillin in the crystal is in zwitterionic form and concentrations of this same form are quite relevant in solutions at physiological pH. Experimental and theoretical results allowed identification of specific features for polymorph characterization. Bands typical of the different polymorphs are identified both in IR and Raman spectra: in particular in the NH stretching region (IR), in the amide I+δNH region (both techniques), in the 1520-1490cm(-1) region (IR), in the 1320-1300cm(-1) and 1280-1220cm(-1) (IR), in the 1200-1170cm(-1) (Raman), in the amide V region (IR), and, finally, in the 715-640cm(-1) and 220-200cm(-1) (Raman). Interconversion among different polymorphs was investigated by hot-stage Raman spectroscopy and thermal analysis, clarifying the complex pattern of transformations undergone as a function of temperature and heating rate. In particular, DSC scans show how the trihydrate crystals transform into anhydrous forms on heating. Finally, stability tests demonstrated, after a two years period, that no transformation or degradation of the polymorphs occurred.

  7. Ventricular Septal Perforation Caused by the Strut of a Mitral Valve Bioprosthesis.

    PubMed

    Dagnegård, Hanna H; Ugander, Martin; Liska, Jan; Källner, Göran G

    2016-03-01

    Ventricular rupture is a well-known complication of mitral valve replacement. We report a rare complication in which the strut of a recently implanted mitral bioprosthesis eroded through the ventricular septum. We present the strategy of the reoperation in which the sutures holding the repair patch were also used to support the new prosthesis. In addition to ventricular rupture and obstruction of the left ventricular outflow tract by a mitral bioprosthesis, the risk of iatrogenic ventricular septal defect (VSD) should be considered when choosing, sizing, and implanting a mitral bioprosthesis. PMID:26897197

  8. An ECG changed the life of a young boy: a case of arrhythmogenic right ventricular dysplasia

    PubMed Central

    Altun, Ibrahim; Akin, Fatih; Sahin, Cem; Beydilli, Halil

    2014-01-01

    Arrhythmogenic right ventricular dysplasia (ARVD) is a progressive condition with the right ventricular myocardium being replaced by fibrofatty tissue. It is a hereditary disorder mostly caused by desmosome gene mutations. The prevalence of arrhythmogenic right ventricular cardiomyopathy is about 1/1000–5000. Clinical presentation is usually related to ventricular tachycardias, syncope, presyncope or ventricular fibrillation leading to cardiac arrest, mostly in young people and athletes. We report a case of a 17-year-old boy from Turkey, who was referred to our cardiology department for an ECG, required of him prior to joining a football team. PMID:25344388

  9. Duration of diastole versus cycle length as correlates of left ventricular ejection time

    NASA Technical Reports Server (NTRS)

    Weisdorf, D.; Spodick, D. H.

    1976-01-01

    Studies were done on 82 normal subjects to evaluate cycle length vs duration of diastole as determinants of left ventricular ejection time. Cycle length and its reciprocal, heart rate, had the highest correlation with left ventricular ejection time. Removal of the self-correlation of left ventricular ejection time within cycle length reduces the correlation so that, of all intervals, duration of diastole had the highest correlation as a determinant of left ventricular ejection time. Cycle length and heart rate remain valuable as spuriously close but not misleading correlates for predicting or correcting left ventricular ejection time.

  10. A case of hybrid closure of a muscular ventricular septal defect: anatomical complexity and surgical management.

    PubMed

    Karimi, Mohsen; Hulsebus, Elise; Murdison, Kenneth; Wiles, Henry

    2012-06-01

    Complex muscular ventricular septal defect poses difficult surgical management and is associated with high morbidity and mortality despite advancements in surgical therapy. Device closure of muscular ventricular septal defect has been encouraging and has been used in hybrid approach at a few centres. However, device closure has some limitations in patients with complex muscular ventricular septal defect. We report a case of perventricular device closure of a complex muscular ventricular septal defect in a beating heart with entrapped right ventricular disc and its surgical management.

  11. Coordinating cardiomyocyte interactions to direct ventricular chamber morphogenesis.

    PubMed

    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

    2016-06-29

    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 comprises 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 and non-compaction cardiomyopathies, it remains unclear how embryonic cardiomyocytes assemble to form ventricular wall layers of appropriate spatial dimensions and myocardial mass. Here we use advanced genetic and imaging tools in zebrafish to reveal an interplay between myocardial Notch and Erbb2 signalling that directs the spatial allocation of myocardial cells to their proper morphological positions in the ventricular wall. Although previous studies have shown that endocardial Notch signalling non-cell-autonomously promotes myocardial trabeculation through Erbb2 and bone morphogenetic protein (BMP) signalling, we discover that distinct ventricular cardiomyocyte clusters exhibit myocardial Notch activity that cell-autonomously inhibits Erbb2 signalling and prevents cardiomyocyte sprouting and trabeculation. Myocardial-specific Notch inactivation leads to ventricles of reduced size and increased wall thickness because of 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 signalling is activated non-cell-autonomously by neighbouring 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 provide insight into the cellular dynamics of how diverse cell lineages organize to create form.

  12. J point elevation as a predictor of premature ventricular beats.

    PubMed

    Matoshvili, Z; Petriashvili, Sh; Archvadze, A; Azaladze, I

    2014-01-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. 36 patients were included in this observation. There are 36 patients (19-68 years old) with early repolarization ECG patterns. All this 36 patients were divided into two groups according to their level of J point elevation. First group consisted of 12 patients with J point elevation ≥0,15 mV; second group - of 24 patients with J point elevation <0,15 mV. We make 24 h ECG holter monitoring all this patients to evaluate absolute number of premature ventricular beat during 24 h. Before and during this monitoring patients don't take any antyarrhythmic drugs. In the first group (J point elevation ≥0,15 mV) sum of premature ventricular beats were 27432, in the second group (J point elevation <0,15 mV) sum of premature ventricular beats were 31 896. The results of this observational study shows that there is 1,72 fold higher number of premature ventricular beats in first group. So, J point elevation equal or more then 0,15 mV, is more arrhythmogenic and induces premature ventricular beats. This is principally new and very important result.

  13. Normal rate of ventricular emptying in valvular aortic stenosis.

    PubMed Central

    Lederman, S M; Gash, A K; Bove, A A; Spann, J F

    1981-01-01

    The delayed upstroke of the arterial pulse in valvular aortic stenosis has been attributed, in part, to prolonged left ventricular emptying. Left ventricular emptying rate, however, has not been measured in aortic stenosis. We assessed the rate of left ventricular emptying by computer analysis of biplane cineangiograms in seven normal subjects, six patients with mild to moderate aortic stenosis, and 12 patients with severe aortic stenosis. As an indicator of delayed arterial pulse rise, T time index (time to half maximum aortic pressure corrected for heart rate) was measured in each group. T time index averaged 0.07 +/- 0.01 units in normal subjects, 0.14 +/- 0.04 units in the patients with mild to moderate aortic stenosis, and 0.13 +/- 0.05 units in those with severe aortic stenosis. Patients with mild to moderate and severe aortic stenosis differed significantly from normal subjects. Relative emptying rates were defined as the percentage of initial systolic volume ejected divided by the percentage of systole elapsed. These relative emptying rates were determined during the first, second, and third thirds of systole in all three groups. No significant decrease in the relative rate of left ventricular emptying was noted when each group of patients with aortic stenosis was compared with the normal subjects. Neither was there slowing in the actual rate of ejection of blood in ml per second throughout systole. We conclude that the rate of ventricular emptying is normal in aortic stenosis and does not explain the arterial pulse delay in this disease. PMID:7295438

  14. Molsidomine prevents post-ischaemic ventricular fibrillation in dogs.

    PubMed Central

    Cano, J. P.; Guillen, J. C.; Jouve, R.; Langlet, F.; Puddu, P. E.; Rolland, P. H.; Serradimigni, A.

    1986-01-01

    Forty anaesthetized dogs were subjected to left circumflex coronary artery ligation followed by reperfusion. Molsidomine was randomly administered to 20 dogs (50 micrograms kg-1 as an i.v. bolus - 15 min prior to coronary occlusion - followed by an infusion of 0.05 micrograms kg-1 min-1. Standard electrocardiographic leads 2 and 3 were continuously recorded to measure ST segment and delta R% changes and to document both the number of ventricular premature beats and the onset of ventricular fibrillation; aortic pressure and cardiac output were measured; thromboxane B2 plasma levels, platelet aggregation produced by ADP, and molsidomine plasma levels were determined before and at 10, 30 and 75 min after the start of the drug protocol. Molsidomine protected the treated animals from early (10 min) post-ischaemic ventricular fibrillation (0 of 20 vs 6 of 20, P = 0.0202), reduced the incidence of overall post-occlusion ventricular fibrillation (3 of 20 vs 10 of 20, P = 0.0407) and improved the total survival rate (P = 0.0067). In molsidomine treated dogs: mean aortic pressure and the rate-pressure product were lowered 10 min after the start of the drug; immediate post-occlusion (3 min) ST segment changes (0.82 +/- 0.52 vs 1.52 +/- 0.78 mV, P less than 0.025) and delta R% changes (37 +/- 50 vs 90 +/- 84%, P less than 0.025) were less marked; the number of ventricular premature beats was lowered and finally, a progressive decline of platelet aggregation produced by ADP was achieved after 75 min of drug infusion. These results were obtained in the presence of mean plasma levels of molsidomine ranging from 20 to 28 ng ml-1. The time-action curve of the antifibrillatory effect of molsidomine parallels those at the level of post-ischaemic electrocardiographic changes. Images Figure 2 PMID:3755634

  15. Coordinating cardiomyocyte interactions to direct ventricular chamber morphogenesis.

    PubMed

    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

    2016-06-30

    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 comprises 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 and non-compaction cardiomyopathies, it remains unclear how embryonic cardiomyocytes assemble to form ventricular wall layers of appropriate spatial dimensions and myocardial mass. Here we use advanced genetic and imaging tools in zebrafish to reveal an interplay between myocardial Notch and Erbb2 signalling that directs the spatial allocation of myocardial cells to their proper morphological positions in the ventricular wall. Although previous studies have shown that endocardial Notch signalling non-cell-autonomously promotes myocardial trabeculation through Erbb2 and bone morphogenetic protein (BMP) signalling, we discover that distinct ventricular cardiomyocyte clusters exhibit myocardial Notch activity that cell-autonomously inhibits Erbb2 signalling and prevents cardiomyocyte sprouting and trabeculation. Myocardial-specific Notch inactivation leads to ventricles of reduced size and increased wall thickness because of 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 signalling is activated non-cell-autonomously by neighbouring 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 provide insight into the cellular dynamics of how diverse cell lineages organize to create form. PMID:27357797

  16. Neutral behavior of shared polymorphism

    PubMed Central

    Clark, Andrew G.

    1997-01-01

    Several cases have been described in the literature where genetic polymorphism appears to be shared between a pair of species. Here we examine the distribution of times to random loss of shared polymorphism in the context of the neutral Wright–Fisher model. Order statistics are used to obtain the distribution of times to loss of a shared polymorphism based on Kimura’s solution to the diffusion approximation of the Wright–Fisher model. In a single species, the expected absorption time for a neutral allele having an initial allele frequency of ½ is 2.77 N generations. If two species initially share a polymorphism, that shared polymorphism is lost as soon as either of two species undergoes fixation. The loss of a shared polymorphism thus occurs sooner than loss of polymorphism in a single species and has an expected time of 1.7 N generations. Molecular sequences of genes with shared polymorphism may be characterized by the count of the number of sites that segregate in both species for the same nucleotides (or amino acids). The distribution of the expected numbers of these shared polymorphic sites also is obtained. Shared polymorphism appears to be more likely at genetic loci that have an unusually large number of segregating alleles, and the neutral coalescent proves to be very useful in determining the probability of shared allelic lineages expected by chance. These results are related to examples of shared polymorphism in the literature. PMID:9223256

  17. Crystallization and transitions of sulfamerazine polymorphs.

    PubMed

    Zhang, Geoff G Z; Gu, Chonghui; Zell, Mark T; Burkhardt, R Todd; Munson, Eric J; Grant, David J W

    2002-04-01

    A bulk powder of sulfamerazine polymorph II in a narrow distribution of particle size was prepared for the first time. The two known sulfamerazine polymorphs, I and II, were physically characterized by optical microscopy, powder X-ray diffractometry, differential scanning calorimetry, carbon-13 solid-state nuclear magnetic resonance spectroscopy, and measurements of aqueous solubility and density. The thermodynamics and kinetics of the transition between the polymorphs was examined under various pharmaceutically relevant conditions, such as heating, cooling, milling, compaction, and contact with solvents. The two polymorphs were found to be enantiotropes with slow kinetics of interconversion. The thermodynamic transition temperature lies between 51 and 54 degrees C, with polymorph II stable at lower temperatures. Ostwald's Rule of Stages explains the crystallization of the polymorphs from various solvents and may account for the delay in the discovery of polymorph II. PMID:11948548

  18. Evaluation of left ventricular scar identification from contrast enhanced magnetic resonance imaging for guidance of ventricular catheter ablation therapy

    NASA Astrophysics Data System (ADS)

    Rettmann, M. E.; Lehmann, H. I.; Johnson, S. B.; Packer, D. L.

    2016-03-01

    Patients with ventricular arrhythmias typically exhibit myocardial scarring, which is believed to be an important anatomic substrate for reentrant circuits, thereby making these regions a key target in catheter ablation therapy. In ablation therapy, a catheter is guided into the left ventricle and radiofrequency energy is delivered into the tissue to interrupt arrhythmic electrical pathways. Low bipolar voltage regions are typically localized during the procedure through point-by-point construction of an electroanatomic map by sampling the endocardial surface with the ablation catheter and are used as a surrogate for myocardial scar. This process is time consuming, requires significant skill, and has the potential to miss low voltage sites. This has led to efforts to quantify myocardial scar preoperatively using delayed, contrast-enhanced MRI. In this paper, we evaluate the utility of left ventricular scar identification from delayed contrast enhanced magnetic resonance imaging for guidance of catheter ablation of ventricular arrhythmias. Myocardial infarcts were created in three canines followed by a delayed, contrast enhanced MRI scan and electroanatomic mapping. The left ventricle and myocardial scar is segmented from preoperative MRI images and sampled points from the procedural electroanatomical map are registered to the segmented endocardial surface. Sampled points with low bipolar voltage points visually align with the segmented scar regions. This work demonstrates the potential utility of using preoperative delayed, enhanced MRI to identify myocardial scarring for guidance of ventricular catheter ablation therapy.

  19. Shoshin beriberi with vasospastic angina pectoris possible mechanism of mid-ventricular obstruction: possible mechanism of mid-ventricular obstruction.

    PubMed

    Ito, Masahiro; Tanabe, Yasuhiko; Suzuki, Kaoru; Kumakura, Makoto; Aizawa, Yoshifusa

    2002-11-01

    A 73-year-old heavy drinker was admitted to hospital in a state of shock. He had been suffering from frequent angina at rest, causing him to drink more heavily in an effort to overcome his anginal chest pain. He had been drinking hard each day and had not eaten for 4 weeks. His hemodynamic state on admission showed high-output heart failure. Echocardiography revealed hyperkinesis of the left ventricle and mid-ventricular obstruction with peak intraventricular gradients of 30 mmHg. Although no improvement was seen despite administering the maximal dose in catecholamine therapy, his condition improved rapidly after vitamin B(1) was administered. Cardiac catheterization revealed mid-ventricular obstruction with an apical aneurysm. Coronary artery spasm was induced by injecting acetylcholine in the distal site of the left anterior descending artery, which perfused the area of the apical aneurysm. In the present case, both left ventricular hyperkinesis caused by shoshin beriberi and apical myocardial infarction caused by frequent coronary spasms produced mid-ventricular obstruction with an apical aneurysm.

  20. Elucidation of the spatial ventricular gradient and its link with dispersion of repolarization.

    PubMed

    Draisma, Harmen H M; Schalij, Martin J; van der Wall, Ernst E; Swenne, Cees A

    2006-09-01

    The ventricular gradient, a notion conceived by Wilson et al during the 1930s, has contributed considerably to a better understanding of the ECG manifestations of the cardiac repolarization process. The power of the ventricular gradient is its ability to assess the primary factors that contribute to the T wave (i.e., heterogeneity of action potential morphology throughout the ventricles) in the presence of secondary factors contributing to the T wave (i.e., heterogeneity in ventricular depolarization instants). Where T-wave morphology is an ECG expression of heterogeneity of the repolarization, the ventricular gradient discriminates between primary or secondary causes of such heterogeneity. Besides the spatial ventricular gradient (Burger's three-dimensional elaboration of Wilson's two-dimensional concept), body surface mapping of local components of the ventricular gradient has emerged as a technique for assessing local ventricular action potential duration heterogeneity. The latter is believed to contribute to localization of arrhythmogenic areas in the heart. The spatial ventricular gradient, which can be computed on the basis of a regular routine ECG and does not require body surface mapping, aims to assess the overall heterogeneity of ventricular action potential morphology. This review addresses the nature and diagnostic potential of the spatial ventricular gradient. The main focus is the role of the spatial ventricular gradient in ECG assessment of dispersion of repolarization, a key factor in arrhythmogeneity.

  1. Postoperative thallium-201 myocardial images. Evidence of regression of right ventricular hypertrophy in man.

    PubMed Central

    Yamazaki, H; Tsugu, T; Handa, S; Takagi, Y; Ohsuzu, F; Kondo, M; Kubo, A; Inoue, T; Nakamura, Y

    1982-01-01

    Thallium-201 myocardial scintigraphic studies were performed on 24 patients with chronic right ventricular overload before and after surgical correction of haemodynamic overload. The ages of the patients ranged from 20 to 65 years (mean 39 years) at operation. The degree of right ventricular visualisation remained essentially unchanged in an early postoperative study (four to 60 days), though a decrease in right ventricular cavity size was noted in patients with right ventricular volume overload. On later follow-up (18 to 36 months), thallium uptake in the right ventricle was definitely less than before operation in all 13 patients studied at this time. Because thallium-201 radioactivity reflects myocardial blood flow and mass, our study indicates that right ventricular hypertrophy is largely reversible. Thus, thallium-201 myocardial scintigraphy can be used to assess non-invasively regression of right ventricular hypertrophy in patients with right ventricular overload. Images PMID:6215051

  2. Left atrial appendage dysfunction in a patient with premature ventricular contractions - a risk factor for stroke?

    PubMed

    Patel, Sandeep M; Ackerman, Michael J; Asirvatham, Samuel J

    2013-01-01

    A 16-year-old female with ventricular dysfunction and frequent ventricular arrhythmia presented with a cardioembolic stroke. Prior electrophysiology study and ablation was performed for ventricular tachycardia (VT). For remaining ventricular ectopy, the patient was maintained on carvedilol and mexiletine. After one year on this regimen, she presented with an acute stroke. Transesophageal echocardiography revealed no evidence of an intracardiac or ventricular thrombus but demonstrated markedly decreased left atrial appendage (LAA) flow velocity worsened during frequent premature ventricular contractions (PVC). In the absence of atrial fibrillation (AF), the LAA dysfunction was considered secondary to the frequent PVCs and was thought to be the underlying cause for the stroke. We present this case to highlight a potential under recognized association between LAA dysfunction and ventricular arrhythmia, similar to that observed with atrioventricular dyssynchronous pacing. PMID:24086095

  3. The effect of sildenafil on right ventricular remodeling in a rat model of monocrotaline-induced right ventricular failure

    PubMed Central

    Bae, Hyun Kyung; Lee, Hyeryon; Kim, Kwan Chang

    2016-01-01

    Purpose Pulmonary arterial hypertension (PAH) leads to right ventricular failure (RVF) as well as an increase in pulmonary vascular resistance. Our purpose was to study the effect of sildenafil on right ventricular remodeling in a rat model of monocrotaline (MCT)-induced RVF. Methods The rats were distributed randomly into 3 groups. The control (C) group, the monocrotaline (M) group (MCT 60 mg/kg) and the sildenafil (S) group (MCT 60 mg/kg+ sildenafil 30 mg/kg/day for 28 days). Masson Trichrome staining was used for heart tissues. Western blot analysis and immunohistochemical staining were performed. Results The mean right ventricular pressure (RVP) was significantly lower in the S group at weeks 1, 2, and 4. The number of intra-acinar arteries and the medial wall thickness of the pulmonary arterioles significantly lessened in the S group at week 4. The collagen content also decreased in heart tissues in the S group at week 4. Protein expression levels of B-cell lymphoma-2 (Bcl-2)-associated X, caspase-3, Bcl-2, interleukin (IL)-6, matrix metalloproteinase (MMP)-2, endothelial nitric oxide synthase (eNOS), endothelin (ET)-1 and ET receptor A (ERA) in lung tissues greatly decreased in the S group at week 4 according to immunohistochemical staining. According to Western blotting, protein expression levels of troponin I, brain natriuretic peptide, caspase-3, Bcl-2, tumor necrosis factor-α, IL-6, MMP-2, eNOS, ET-1, and ERA in heart tissues greatly diminished in the S group at week 4. Conclusion Sildenafil alleviated right ventricular hypertrophy and mean RVP. These data suggest that sildenafil improves right ventricular function. PMID:27462355

  4. Superhard Monoclinic Polymorph of Carbon

    SciTech Connect

    Li, Quan; Ma, Yanming; Oganov, Artem R.; Wang, Hongbo; Wang, Hui; Xu, Ying; Cui, Tian; Mao, Ho-Kwang; Zou, Guangtian; Jilin; SBU; CIW

    2009-05-08

    We report a novel phase of carbon possessing a monoclinic C2/m structure (8 atoms/cell) identified using an ab initio evolutionary structural search. This polymorph, which we call M-carbon, is related to the (2x1) reconstruction of the (111) surface of diamond and can also be viewed as a distorted (through sliding and buckling of the sheets) form of graphite. It is stable over cold-compressed graphite above 13.4 GPa. The simulated x-ray diffraction pattern and near K-edge spectroscopy are in satisfactory agreement with the experimental data [W.L. Mao et al., Science 302, 425 (2003)] on overcompressed graphite. The hardness and bulk modulus of this new carbon polymorph are calculated to be 83.1 and 431.2 GPa, respectively, which are comparable to those of diamond.

  5. Milk casein polymorphism in man.

    PubMed

    Ponzone, A; Voglino, G F

    1976-06-01

    Urea-starch-gel electrophoresis was used to examine 175 casein samples, 130 collected at random from women from the urban area of Turin, and 45 from women resident in villages in the Sardinian hinterland. Two polymorphic systems controlling alpha- and beta-casein were demonstrated in both groups, together with similar gene frequencies for individual alleles. In addition, a rare variant was discovered in the Sardinian group.

  6. The Single Nucleotide Polymorphism Consortium

    NASA Technical Reports Server (NTRS)

    Morgan, Michael

    2003-01-01

    I want to discuss both the Single Nucleotide Polymorphism (SNP) Consortium and the Human Genome Project. I am afraid most of my presentation will be thin on law and possibly too high on rhetoric. Having been engaged in a personal and direct way with these issues as a trained scientist, I find it quite difficult to be always as objective as I ought to be.

  7. Increased dispersion of ventricular repolarization and ventricular tachyarrhythmias in the globally ischaemic rabbit heart.

    PubMed

    Kurz, R W; Xiao-Lin, R; Franz, M R

    1993-11-01

    Contemporary concepts of ischaemic ventricular tachyarrhythmias (VTA) are based on increased electrophysiological heterogeneity of the myocardium. We developed a multi-site monophasic action potential recording system for an isolated rabbit heart to study the effects of global ischaemia on the electrophysiological properties at different ventricular sites simultaneously. The hearts were paced from the right ventricle (RV), and conduction time (CT), action potential duration (APD) and total repolarization time (TRT = [CT + APD]) were measured during normal perfusion and ischaemia. The dispersion of these parameters was calculated as the maximal difference between simultaneous recordings. Inducibility of VTA by programmed extrastimulation (ES) was investigated under normal and ischaemic conditions. During global ischaemia, CT increased progressively, showing a faster and greater increase at the left ventricle (LV) than at the RV. After 10 min the prolongation of CT reached a plateau at the LV while it continued to rise in the RV. The dispersion of CT increased from 14.5 +/- 2.7 ms during normal perfusion to a maximum of 79.8 +/- 17.2 ms after 14 min of ischaemia (P < 0.0001). APD was uniform at the three sites (190.9 +/- 10.2, 185.0 +/- 8.6 and 179.3 +/- 9.8 ms, ns) during normal perfusion but changed non-uniformly during ischaemia. There was a transient lengthening of APD until 1 and 3 min of ischaemia at the LV sites followed by a rapid shortening of APD. At the RV site, APD continued to increase until 5 min of ischaemia and then shortened gradually. Consequently, dispersion of APD showed a rapid initial rise from 17.7 +/- 2.7 ms to 77.8 +/- 10.2 ms (P < 0.0001) followed by a slower final increase. TRT was uniform during normal perfusion (210.4 +/- 10.3, 213.1 +/- 7.8, 212.1 +/- 10.3 ms, ns) but became non-uniform during global ischaemia. The dispersion of TRT increased from 15.4 +/- 4.2 ms to 92.6 +/- 23.2 ms (P < 0.0001) during 14 min of global ischaemia. Both CT

  8. [Experimental principles for preserving annulo-ventricular integrity of the mitral valve].

    PubMed

    Gams, E; Schad, H; Heimisch, W

    1996-06-01

    Despite numerous improvement in cardiac surgery the results in mitral valve replacement are still not satisfactory, since impaired left ventricular function continues to be a problem during the postoperative course. In order to investigate the effect of mitral valve replacement on left ventricular function canine experiments were performed: During extracorporeal circulation bileaflet mitral valve prostheses were implanted preserving the ventriculo-annular continuity. Flexible wires were slung around the chordae of the subvalvular mitral apparatus and brought to the outside through the left ventricular wall. Left ventricular diameters were measured by sonomicrometry, left ventricular stroke volume, left ventricular enddiastolic volume and ejection fraction by dye dilution technique as well as left ventricular and aortic pressure by catheter tip manometers. After finishing cardiopulmonary bypass control values were registered and different preload values achieved by volume loading with blood transfusions to left ventricular enddiastolic pressures of 12 mm Hg. Subsequently under normovolumic conditions the chordae tendineae of the anterior and posterior papillary muscles of the mitral valve were cut from the outside, while the heart was beating, by application of electrocautery on the steel wires. Following severance of the ventriculo-annular continuity of the mitral valve again function curves of left ventricular hemodynamics were made during volume transfusions. When the chordae had been divided the left ventricular enddiastolic diameter increased by 10% in the major axis, while in the minor axis no significant changes occurred. The systolic shortening was impaired substantially by reduction of 43% during the ejection phase when the subvalvular mitral apparatus had been severed. Left ventricular enddiastolic volume was increased by 18% at any preload level, while left ventricular ejection fraction was reduced by 16%. Consequently left ventricular stroke volume was

  9. Positive inotropic effect of porcine left ventricular extract on canine ventricular muscle.

    PubMed Central

    Navaratnam, S.; Chau, T.; Agbanyo, M.; Bose, D.; Khatter, J. C.

    1990-01-01

    1. We previously isolated an extract from porcine left ventricle that possessed digitalis-like properties such as inhibition of cardiac and kidney Na+, K(+)-ATPase, displacement of [3H]-ouabain from its binding sites and cross reactivity with digoxin antibodies. The extract also had a positive inotropic effect on the guinea-pig heart. 2. In the present study the positive inotropic response of the extract was characterized in canine right ventricular trabeculae. Maximum inotropic response (501 +/- 20%) was produced by 300 microliters and the half maximal increase occurred with 125 microliters of the extract. 3. Ouabagenin produced aftercontractions in rapidly paced trabeculae. Equipotent and even greater amounts of the extract did not produce aftercontractions. 4. The extract increased the amplitude of the delayed component (P2) of biphasic contractions produced by replacing about 92-96% of the external Ca with Sr. A smaller increase in the size of the early component (P1) was also seen. 5. The extract decreased post-rest potentiation after rest for 30s and 2 min. After 8 min of rest, post-rest potentiation was converted to post-rest depression. 6. The extract (20 microliters) produced a decrease in the amplitude of the post-rest rapid cooling contracture (RCC) at all rest intervals. The steady state RCC, although greater than that in the control muscle, was increased to a lesser extent than the size of the steady state electrically driven contractions. 7. It is suggested that the extract from porcine left ventricle produces a positive inotropic response by increasing the trans-sarcolemmal influx of Ca.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2257439

  10. Right Ventricular Apical Flattening as an Echocardiographic Screening Tool for Right Ventricular Enlargement.

    PubMed

    Buddhe, Sujatha; Ferguson, Mark; Arya, Bhawna; Soriano, Brian D

    2016-03-01

    Right ventricular dilation is a common complication after tetralogy of Fallot (TOF) repair. Traditional echocardiographic assessments are imprecise due to the RV's location and complex geometry. We propose a novel echocardiographic measurement: RV apical flattening (RVAF) as a screening tool to help identify subjects with severe RV dilation. Patients with repaired TOF who had both echocardiograms and CMR's within 6-month interval at our institution were included in the study. The RVAF was measured in the four-chamber echocardiographic view as the minor length of RV cavity at the level of RV apical endocardium. Subjects were divided into two groups (group I: RVEDVi ≥ 150 ml/m(2) and group II; RVEDVi < 150 ml/m(2)). Echocardiogram and CMR data were compared between groups. A total of 75 subjects were included in the study. Mean age was 12.8 ± 3.6 years. Group I had 36 subjects, and group II had 39 subjects. The mean RVAF was significantly higher in group I (2.7 ± 0.5 cm) compared with group II (1.7 ± 0.4 cm; p < 0.001). There was significant correlation between RVAF and RVEDVi (r = 0.81; p < 0.001). By ROC analysis, an RVAF cutoff value of 2.0 cm had 94 % sensitivity and 77 % specificity in identifying severe RV dilation (area under the curve 0.95). RVAF is a simple and effective echocardiographic screening tool to help identify severe RV dilation. In conjunction with other 2D echocardiographic parameters, this technique would help further refine echocardiography-guided patient selection for timing of CMR and pulmonary valve replacement.

  11. Three-wall segment (TriSeg) model describing mechanics and hemodynamics of ventricular interaction.

    PubMed

    Lumens, Joost; Delhaas, Tammo; Kirn, Borut; Arts, Theo

    2009-11-01

    A mathematical model (TriSeg model) of ventricular mechanics incorporating mechanical interaction of the left and right ventricular free walls and the interventricular septum is presented. Global left and right ventricular pump mechanics were related to representative myofiber mechanics in the three ventricular walls, satisfying the principle of conservation of energy. The walls were mechanically coupled satisfying tensile force equilibrium in the junction. Wall sizes and masses were rendered by adaptation to normalize mechanical myofiber load to physiological standard levels. The TriSeg model was implemented in the previously published lumped closed-loop CircAdapt model of heart and circulation. Simulation results of cardiac mechanics and hemodynamics during normal ventricular loading, acute pulmonary hypertension, and chronic pulmonary hypertension (including load adaptation) agreed with clinical data as obtained in healthy volunteers and pulmonary hypertension patients. In chronic pulmonary hypertension, the model predicted right ventricular free wall hypertrophy, increased systolic pulmonary flow acceleration, and increased right ventricular isovolumic contraction and relaxation times. Furthermore, septal curvature decreased linearly with its transmural pressure difference. In conclusion, the TriSeg model enables realistic simulation of ventricular mechanics including interaction between left and right ventricular pump mechanics, dynamics of septal geometry, and myofiber mechanics in the three ventricular walls.

  12. Estimation of left ventricular mass in conscious dogs

    NASA Technical Reports Server (NTRS)

    Coleman, Bernell; Cothran, Laval N.; Ison-Franklin, E. L.; Hawthorne, E. W.

    1986-01-01

    A method for the assessment of the development or the regression of left ventricular hypertrophy (LVH) in a conscious instrumented animal is described. First, the single-slice short-axis area-length method for estimating the left-ventricular mass (LVM) and volume (LVV) was validated in 24 formaldehyde-fixed canine hearts, and a regression equation was developed that could be used in the intact animal to correct the sonomicrometrically estimated LVM. The LVM-assessment method, which uses the combined techniques of echocardiography and sonomicrometry (in conjunction with the regression equation), was shown to provide reliable and reproducible day-to-day estimates of LVM and LVV, and to be sensitive enough to detect serial changes during the development of LVH.

  13. Hemodynamic-impact-based prioritization of ventricular tachycardia alarms.

    PubMed

    Desai, Kalpit; Lexa, Michael; Matthews, Brett; Genc, Sahika

    2014-01-01

    Ventricular tachycardia (V-tach) is a very serious condition that occurs when the ventricles are driven at high rates. The abnormal excitation pathways make ventricular contraction less synchronous resulting in less effective filling and emptying of the left ventricles. However, almost half of the V-tach alarms declared through processing of patterns observed in electrocardiography are not clinically actionable. The focus of this study is to provide guidance on determining whether a technically-correct V-tach alarm is clinically-actionable by determining its "hemodynamic impact". A supervisory learning approach based on conditional inference trees to determine the hemodynamic impact of a V-tach alarm based on extracted features is described. According to preliminary results on a subset of Multiparameter intelligent monitoring in intensive care II (MIMIC-II) database, true positive rate of more than 90% can be achieved. PMID:25570734

  14. T Wave Alternans And Ventricular Tachyarrhythmia Risk Stratification: A Review

    PubMed Central

    Takagi, Masahiko; Yoshikawa, Junichi

    2003-01-01

    Sudden cardiac death (SCD) is one of the leading causes of mortality in industrialized countries. Thus, identifying patients at high risk of SCD is an important goal. T wave alternans (TWA) is a new method for identifying patients with lethal ventricular tachyarrhythmias, and is dependent on heart rate. The maximal predictive accuracy is achieved at heart rates between 100 and 120 bpm, so that TWA is usually measured during exercise, phamacological stress, or atrial pacing. It has been shown that TWA has high sensitivity and negative predictive value for predicting SCD after myocardial infarction and is also useful for predicting SCD in patients with nonischemic cardiomyopathy. Although the implantable cardioverter defibrillator (ICD) is now the primary therapy for preventing SCD, it is difficult to identify those patients who are susceptible to lethal ventricular tachyarrhythmias for primary prevention. In the prediction of SCD, TWA can be used as a screening test of appropriate patients for further electrophysiological examination and therapy. PMID:16943959

  15. Acquired Fontan paradox in isolated right ventricular cardiomyopathy.

    PubMed

    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

  16. 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

  17. Vortex Formation Time is Not an Index of Ventricular Function

    PubMed Central

    Vlachos, Pavlos P.; Little, William C.

    2015-01-01

    The diastolic intraventricular ring vortex formation and pinch-off process may provide clinically useful insights into diastolic function in health and disease. The vortex ring formation time (FT) concept, based on hydrodynamic experiments dealing with unconfined (large tank) flow, has attracted considerable attention and popularity. Dynamic conditions evolving within the very confined space of a filling, expansible ventricular chamber with relaxing and rebounding viscoelastic muscular boundaries, diverge from unconfined (large tank) flow and encompass rebounding walls’ suction and myocardial relaxation. Indeed, clinical/physiological findings seeking validation in vivo failed to support the notion that FT is an index of normal/abnormal diastolic ventricular function. Therefore, FT as originally proposed cannot and should not be utilized as such an index. Evidently, physiologically accurate models accounting for coupled hydrodynamic and (patho)physiological myocardial wall interactions with the intraventricular flow are still needed to enhance our understanding and yield diastolic function indices useful and reliable in the clinical setting. PMID:25609509

  18. Double outlet from chambers of left ventricular morphology.

    PubMed Central

    Coto, E O; Jimenez, M Q; Castaneda, A R; Rufilanchas, J J; Deverall, P B

    1979-01-01

    This series of 5 cases with double outlet of morphologically left ventricular chamber includes 4 found during a review of 1700 heart specimens (incidence 0.23%) and 1 found at operation and successfully corrected. Abnormal atrioventricular connection precluding total correction was present in the 4 anatomical cases. Clinical diagnosis may be difficult and it is suggested that axial cineangiography may make anatomical diagnosis easier. Absence of the infundibular septum and aortic laevoposition are frequent. As some cases can be surgically corrected, accurate information is required on the size of the right ventricle, the morphology and function of the atrioventricular valves, the presence, size, and position of the ventricular septal defect, and the degree and type of outflow tract obstruction. Images PMID:475930

  19. Novel Left Ventricular Assist System® II

    PubMed Central

    Liotta, Domingo

    2004-01-01

    The pump's outflow connector of the Novel Left Ventricular Assist System® I (Novel LVAS® I) has been redesigned to be sutured to the infrarenal abdominal aorta either as a procedure of choice (due to its simplicity) or as an alternative in the presence of an unhealthy descending thoracic aorta. The implantation of the Novel Left Ventricular Assist System® II (Novel LVAS® II) requires only a single passage of the pump's inflow connector through the diaphragm. Of still greater importance, the Novel LVAS II enables a considerably shorter (20- or 22-mm) Dacron vascular graft as the outflow connector to the abdominal infrarenal aorta. The electrocardiogram-synchronized Novel LVAS II possibly ensures the most effective approach to the perfusion of visceral organs and kidneys, while avoiding both excessive mechanical stress on the blood and anatomical and functional damage to the native left ventricle. PMID:15562850

  20. [The design of bionic left ventricular auxiliary pump].

    PubMed

    Jin, Henglin; Hu, Xiaobing; Du, Lei

    2015-01-01

    This paper reports a novel design of bionic left ventricular auxiliary pump, and the characteristic is that elastic diaphragm of pump driven by hydraulic, having smooth, reliable blood supply, can prevent blood clots, can use the flow sensor, pressure sensor detection showing the blood pressure and blood volume at the inlet and outlet of the pump. The pump can go with heart rate synchronization or asynchronous auxiliary by the R wave of human body's ECG. The design goal is realization of bionic throb. Through the animal experiment, the blood pressure waveforms are close to expectations, stable flow can stroke according to the set value, which prove that the pump can meet the requirement for heart disease patients for bionic left ventricular assistant.

  1. Angiocardiographic methods for determination of left ventricular geometry and volume

    NASA Technical Reports Server (NTRS)

    Sandler, H.; Dodge, H. T.

    1974-01-01

    Methods are described for calculating left ventricular (LV) dimensions and chamber volumes from radiographic films. The use of biplane films for the calculation of LV volume and volume change is based on the assumption of an ellipsoidal geometry. Calculation of LV volumes from biplane films usually overestimated known volumes in postmortem hearts regardless of the methods used for volume calculation. The reasons for this are probably best explained by the fact that a smooth-surface ellipse is used to represent the irregular cavity of the LV chamber. LV volume calculated from data in a single plane compared favorably and closely with volumes calculated from biplane films. A table of normal values of ventricular volume established by angiographic studies is presented.

  2. The development of left ventricular torsion and its clinical relevance.

    PubMed

    Shaw, Steven M; Fox, David J; Williams, Simon G

    2008-11-28

    Left ventricular torsion is a measurement derived from the twisting or wringing motion of the heart around its long axis. The calculation is made by measuring the magnitude of rotation at the apex of the heart, and subtracting the rotation at the base. Although the phenomenon of left ventricular twisting was first described in the 17th Century, it wasn't until the 1960s that the first invasive method of measurement was demonstrated. Silver tantalum clips were sutured into the epicardium during cardiac surgery and viewed using cineradiography. Non-invasive torsion measurement has been subsequently developed, adopting Magnetic Resonance Imaging and 2D echocardiography. Interest in the changes of different components of torsion, during various cardiac disease states has developed with the advent of these non-invasive measurement techniques. This review article summarises the history of the development of torsion analysis and describes the known changes of torsion during different clinical circumstances.

  3. Origin of ventricular reflexes caused by coronary arteriography.

    PubMed Central

    Perez-Gomez, F; Garcia-Aguado, A

    1977-01-01

    Left ventricular reflexes have in the past been investigated in anaesthetised animals, generally using an open chest technique. We have studied the degree of bradycardia occurring during coronary arteriography in 200 patients with a view to localising the origin of the ventricular reflexes. We have correlated the decrease of sinus rate with the anatomical distribution and integrity of the coronary tree. The degree of bradycardia was not influenced by the origin of the sinus node or the AV node arteries, while there was a good correlation with the injection of contrast medium into the artery which supplied the inferior wall of the left ventricle. The occurrence of transient sinus arrest was also correlated with the injection into the same artery. The results suggest that the parasympathetic receptors are located mainly in the inferior wall of the left ventricle. This may well be the explanation for the clinical picture of bradycardia, hypotension, and peripheral vasodilatation often seen in acute inferior myocardial infarction. PMID:907775

  4. Right Heart Vortex Entrainment Volume and Right Ventricular Diastolic Dysfunction

    NASA Astrophysics Data System (ADS)

    Browning, James; Hertzberg, Jean; Fenster, Brett; Schroeder, Joyce

    2014-11-01

    Recent advances in cardiac magnetic resonance imaging (CMR) have allowed for the 3-dimensional characterization of blood flow in the right ventricle (RV) and right atrium (RA). In this study, we investigate and quantify differences in the characteristics of coherent rotating flow structures (vortices) in the RA and RV between subjects with right ventricular diastolic dysfunction (RVDD) and normal controls. Fifteen RVDD subjects and 10 age-matched controls underwent same day 3D time resolved CMR and echocardiography. Echocardiography was used to determine RVDD stage as well as pulmonary artery systolic pressure (PASP). CMR data was used for RA and RV vortex quantification and visualization during early and late ventricular diastole. RA and RV vortex entrainment volume is quantified and visualized using the Lambda-2 criterion, and the results are compared between healthy subjects and those with RVDD. The resulting trends are discussed and hypotheses are presented regarding differences in vortex characteristics between healthy and RVDD subjects cohorts.

  5. Right Heart Vorticity and Right Ventricular Diastolic Dysfunction

    NASA Astrophysics Data System (ADS)

    Browning, James; Hertzberg, Jean; Fenster, Brett; Schroeder, Joyce

    2015-11-01

    Recent advances in cardiac magnetic resonance imaging (CMR) have allowed for the 3-dimensional characterization of blood flow in the right ventricle (RV) and right atrium (RA). In this study, we investigate and quantify differences in the characteristics of coherent rotating flow structures (vortices) in the RA and RV between subjects with right ventricular diastolic dysfunction (RVDD) and normal controls. Fifteen RVDD subjects and 10 age-matched controls underwent same day 3D time resolved CMR and echocardiography. Echocardiography was used to determine RVDD stage as well as pulmonary artery systolic pressure (PASP). CMR data was used for RA and RV vortex quantification and visualization during early ventricular diastole and the results are compared between healthy subjects and those with RVDD. The resulting trends are discussed and hypotheses are presented regarding differences in vortex characteristics between healthy and RVDD subjects cohorts.

  6. [Long-term outcome of pharmacological and nonpharmacological treatment for ventricular arrhythmias].

    PubMed

    Ohnishi, S; Kasanuki, H

    2000-03-01

    Recent advances of nonpharmacological therapy such as catheter ablation and implantable cardioverter defibrillator and lessons from the Cardiac Arrhythmia Suppression Trial(CAST) have changed the strategy for ventricular arrhythmias. The safety and efficacy of radiofrequency catheter ablation of symptomatic sustained monomorphic ventricular tachycardia without structural heart disease has made ablation the firstline curative therapy. In idiopathic ventricular fibrillation such as Brugada syndrome, an implantable cardioverter defibrillator is the most effective treatment to prevent sudden cardiac death. In patients with asymptomatic ventricular tachyarrhythmias in heart failure, class I antiarrhythmic drugs should be avoided due to proarrhythmic and negative inotropic effects that may be responsible for increased mortality in some trials. In such patients, amiodarone and beta-blocker may reduce sudden cardiac death. For patients with sustained ventricular tachycardia or ventricular fibrillation in heart failure, amiodarone or implantable cardioverter defibrillator should be considered. In comparison with amiodarone, implantable cardioverter defibrillator markedly reduced sudden death in ventricular tachycardia and ventricular fibrillation survivors in Antiarrhythmics Versus Implantable Defibriltors(AVID). Although better patient selection and clarification of mapping criteria improved the successful ablation rate in patients with structural heart disease, candidates of ablation are few. In patients with extensive structural heart disease, multiple ventricular tachycardias are often present. Catheter ablation of a single ventricular tachycardia may be only palliative. Therefore, implantable cardioverter defibrillator is the most effective treatment to prevent sudden cardiac death, with amiodarone and ablation as the adjunctive therapy to prevent frequent ventricular tachycardia. Furthermore, an implantable cardioverter defibrillator improved survival in selected

  7. Prediction of ventricular arrhythmia events in ischemic heart disease patients with implantable cardioverter-defibrillators.

    PubMed

    Feng, Tianjie; Zhang, Shu; Chen, Keping; Hua, Wei; Ren, Xiaoqing

    2015-10-01

    The aim of the study was to exam the prediction of ventricular arrhythmia events in ischemic heart disease patients with implantable cardioverter-defibrillators (ICD). A total of 123 consecutive patients confirmed ischemia heart disease with ICD were examined. After device implantation, the occurrence of appropriate ICD therapy was noted. Patients were divided into two groups according to the ventricular arrhythmia occurrence. Patients with ventricular arrhythmia occurrence had a significantly great incidence of atrial fibrillation history compare to the no-ventricular arrhythmia occurrence group (8 vs. 39%, P = 0.02). The level of high-sensitive C-reactive protein (hsCRP) baseline was also significantly higher in the ventricular arrhythmia group than in the no ventricular arrhythmia (3.78 ± 1.1 vs. 0.94 ± 0.7, P < 0.01). The taking of β blocker is not common in ventricular arrhythmia group patients than no ventricular arrhythmia group (5 vs. 29%, P = 0.03). By univariate comparison, male sex, the history of atrial fibrillation, and a high level of hsCRP were significant predictors for ventricular arrhythmia occurrence. By multivariate analysis, the atrial fibrillation burden, and had a high level of hsCRP were significant for incidence of ventricular arrhythmia occurrence in ischemic heart disease patients. β-block were more likely to be free from ventricular arrhythmia occurrence. The high level of hsCRP, and the atrial fibrillation burden were strong predictor of ventricular arrhythmia occurrence in secondary prevention ICD recipients with ischemic heart disease. Taking β-blockers was free from ventricular arrhythmia occurrence.

  8. Chronic effects of myocardial infarction on right ventricular function: a noninvasive assessment

    SciTech Connect

    Kaul, S.; Hopkins, J.M.; Shah, P.M.

    1983-10-01

    To assess the chronic effects of myocardial infarction on right ventricular function, 48 subjects were studied utilizing radionuclide angiography and two-dimensional echocardiography. Ten were normal subjects (group I), 11 had previous inferior wall myocardial infarction (group II), 10 had previous anteroseptal infarction (group III), 11 had combined anteroseptal and inferior infarction (group IV) and 6 had extensive anterolateral infarction (group V). The mean (+/- standard deviation) left ventricular ejection fraction was 0.66 +/- 0.03 in group I, 0.58 +/- 0.02 in group II, 0.52 +/- 0.02 in group III, 0.33 +/- 0.03 in group IV and 0.33 +/- 0.01 in group V. No systematic correlation between left and right ventricular ejection fraction was observed among the groups. The mean right ventricular ejection fraction was significantly reduced in the presence of inferior myocardial infarction (0.30 +/- 0.03 in group II and 0.29 +/- 0.03 in group IV compared with 0.43 +/- 0.02 in group I (p less than 0.001)). The group II and IV patients also had increased (p less than 0.001) right ventricular end-diastolic area and decreased (p less than 0.001) right ventricular free wall motion by two-dimensional echocardiography. In the presence of anteroseptal infarction (group III), right ventricular free wall motion was increased (p less than 0.05) compared with normal subjects (group I). Thus, the effects of prior myocardial infarction on right ventricular function depend more on the location of infarction than on the extent of left ventricular dysfunction. Inferior infarction was commonly associated with reduced right ventricular ejection fraction and increased right ventricular end-diastolic area. The right ventricular free wall excursion was increased in the presence of anteroseptal infarction, suggested loss of contribution of interventricular septal contraction to right ventricular ejection.

  9. Kinematic Characterization of Left Ventricular Chamber Stiffness and Relaxation

    NASA Astrophysics Data System (ADS)

    Mossahebi, Sina

    Heart failure is the most common cause of hospitalization today, and diastolic heart failure accounts for 40-50% of cases. Therefore, it is critical to identify diastolic dysfunction at a subclinical stage so that appropriate therapy can be administered before ventricular function is further, and perhaps irreversibly impaired. Basic concepts in physics such as kinematic modeling provide a unique method with which to characterize cardiovascular physiology, specifically diastolic function (DF). The advantage of an approach that is standard in physics, such as the kinematic modeling is its causal formulation that functions in contrast to correlative approaches traditionally utilized in the life sciences. Our research group has pioneered theoretical and experimental quantitative analysis of DF in humans, using both non-invasive (echocardiography, cardiac MRI) and invasive (simultaneous catheterization-echocardiography) methods. Our group developed and validated the Parametrized Diastolic Filling (PDF) formalism which is motivated by basic physiologic principles (LV is a mechanical suction pump at the mitral valve opening) that obey Newton's Laws. PDF formalism is a kinematic model of filling employing an equation of motion, the solution of which accurately predicts all E-wave contours in accordance with the rules of damped harmonic oscillatory motion. The equation's lumped parameters---ventricular stiffness, ventricular viscoelasticity/relaxation and ventricular load---are obtained by solving the 'inverse problem'. The parameters' physiologic significance and clinical utility have been repeatedly demonstrated in multiple clinical settings. In this work we apply our kinematic modeling approach to better understand how the heart works as it fills in order to advance the relationship between physiology and mathematical modeling. Through the use of this modeling, we thereby define and validate novel, causal indexes of diastolic function such as early rapid filling energy

  10. Detection of acute right ventricular infarction by right precordial electrocardiography

    SciTech Connect

    Croft, C.H.; Nicod, P.; Corbett, J.R.; Lewis, S.E.; Huxley, R.; Mukharji, J.; Willerson, J.T.; Rude, R.E.

    1982-09-01

    The value of 0.1 mV or greater of S-T segment elevation in at least one right precordial lead (V4R to V6R) in defining right ventricular myocardial infarction was assessed prospectively in 43 subjects (33 consecutive patients with enzymatically confirmed infarction of varying type and location, 4 patients with unstable angina and 6 healthy volunteers). Patients with acute myocardial infarction were studied with radionuclide ventriculography and /sup 99m/Tc stannous pyrophosphate myocardial scintigraphy 18.2 +/- 14.3 (mean +/- standard deviation) and 85.1 +/- 18.0 hours after the onset of symptoms, respectively. Eleven patients demonstrated right precordial S-T segment elevation and 22 patients did not. Right ventricular ejection fraction was significantly lower in Group A (0.47 +/- 0.11) than in Group B (0.60 +/- 0.12) (p less than 0.01). Right ventricular total wall motion score was 63.8 +/- 15.6 percent of normal in Group A versus 94.3 +/- 8.5 percent in Group B (p less than 0.001). /sup 99m/Tc pyrophosphate uptake (2+ or greater) over the right ventricle occurred in nine patients (81.8 percent) in Group A and in one patient (4.5 percent) in Group B (p less than 0.001). No patient with unstable angina and no healthy volunteer had S-T segment elevation in a right precordial lead. S-T segment elevation of 0.1 mV or greater in one or more of leads V4R to V6R is both highly sensitive (90 percent) and specific (91 percent) in identifying acute right ventricular infarction.

  11. Synthetic Marijuana Induced Acute Nonischemic Left Ventricular Dysfunction.

    PubMed

    Elsheshtawy, Moustafa; Sriganesh, Priatharsini; Virparia, Vasudev; Patel, Falgun; Khanna, Ashok

    2016-01-01

    Synthetic marijuana is an uptrending designer drug currently widely spread in the US. We report a case of acute deterioration of nonischemic left ventricular dysfunction after exposure to synthetic marijuana. This case illustrates the importance of history taking in cardiac patients and identifies a negative cardiovascular effect of synthetic marijuana known as K2, not yet well detected by urine toxicology screening tools. PMID:27119030

  12. Transoccipital endoscopic fenestration of atrial cysts causing ventricular entrapment.

    PubMed

    Ellis, Jason A; McCormick, Paul C; Feldstein, Neil A; Ghatan, Saadi

    2015-06-01

    OBJECT Cystic lesions in the atrium (trigone) of the lateral ventricle may become symptomatic due to obstruction of physiological CSF circulation and/or from mass effect on adjacent structures. A minimally invasive approach that not only allows for straightforward access to multiple regions of the atrial cyst wall, but also enables direct inspection of the entire lateral ventricular system, has not been elaborated. In this paper the authors describe their experience with the endoscopic transoccipital horn approach for treating cystic lesions in the atrium of the lateral ventricle. METHODS A retrospective review was performed of all patients who underwent endoscopic surgical treatment for cysts in the atrium of the lateral ventricle between 1999 and 2014. RESULTS The cohort consisted of 13 consecutive patients who presented with symptomatic lateral ventricular entrapment due to the presence of an atrial cyst. There were 9 male and 4 female patients, with a median age of 5 years. Headache was the most common complaint at presentation. The transoccipital horn approach facilitated successful cyst reduction and fenestration in all cases. Temporal and occipital horn entrapment was reversed in all cases, with reestablishment of a physiological CSF flow pattern throughout the ventricles. Hydrocephalus was also reversed in all patients presenting with this neuroimaging finding at presentation. No cyst or ventricular entrapment was noted to recur during a mean follow-up period of 36 months. No patient in the study cohort required repeat surgery or permanent CSF diversion postoperatively. CONCLUSIONS The endoscopic transoccipital horn approach represents a safe and effective treatment strategy for patients with symptomatic atrial cysts of the lateral ventricle. Using this minimally invasive technique, all poles of the lateral ventricular system can be visualized and the unobstructed flow of CSF can be confirmed after cyst resection obviating the need for additional diversion.

  13. Intracellular Ca(2+) dynamics and the stability of ventricular tachycardia.

    PubMed Central

    Chudin, E; Goldhaber, J; Garfinkel, A; Weiss, J; Kogan, B

    1999-01-01

    Ventricular fibrillation (VF), the major cause of sudden cardiac death, is typically preceded by ventricular tachycardia (VT), but the mechanisms underlying the transition from VT to VF are poorly understood. Intracellular Ca(2+) overload occurs during rapid heart rates typical of VT and is also known to promote arrhythmias. We therefore studied the role of intracellular Ca(2+) dynamics in the transition from VT to VF, using a combined experimental and mathematical modeling approach. Our results show that 1) rapid pacing of rabbit ventricular myocytes at 35 degrees C led to increased intracellular Ca(2+) levels and complex patterns of action potential (AP) configuration and the intracellular Ca(2+) transients; 2) the complex patterns of the Ca(2+) transient arose directly from the dynamics of intracellular Ca(2+) cycling, and were not merely passive responses to beat-to-beat alterations in AP; 3) the complex Ca(2+) dynamics were simulated in a modified version of the Luo-Rudy (LR) ventricular action potential with improved intracellular Ca(2+) dynamics, and showed good agreement with the experimental findings in isolated myocytes; and 4) when incorporated into simulated two-dimensional cardiac tissue, this action potential model produced a form of spiral wave breakup from VT to a VF-like state in which intracellular Ca(2+) dynamics played a key role through its influence on Ca(2+)-sensitive membrane currents such as I(Ca), I(NaCa), and I(ns(Ca)). To the extent that spiral wave breakup is useful as a model for the transition from VT to VF, these findings suggest that intracellular Ca(2+) dynamics may play an important role in the destabilization of VT and its degeneration into VF. PMID:10585917

  14. Evolution and development of ventricular septation in the amniote heart.

    PubMed

    Poelmann, Robert E; Gittenberger-de Groot, Adriana C; Vicente-Steijn, Rebecca; Wisse, Lambertus J; Bartelings, Margot M; Everts, Sonja; Hoppenbrouwers, Tamara; Kruithof, Boudewijn P T; Jensen, Bjarke; de Bruin, Paul W; Hirasawa, Tatsuya; Kuratani, Shigeru; Vonk, Freek; van de Put, Jeanne M M S; de Bakker, Merijn A; Richardson, Michael K

    2014-01-01

    During cardiogenesis the epicardium, covering the surface of the myocardial tube, has been ascribed several functions essential for normal heart development of vertebrates from lampreys to mammals. We investigated a novel function of the epicardium in ventricular development in species with partial and complete septation. These species include reptiles, birds and mammals. Adult turtles, lizards and snakes have a complex ventricle with three cava, partially separated by the horizontal and vertical septa. The crocodilians, birds and mammals with origins some 100 million years apart, however, have a left and right ventricle that are completely separated, being a clear example of convergent evolution. In specific embryonic stages these species show similarities in development, prompting us to investigate the mechanisms underlying epicardial involvement. The primitive ventricle of early embryos becomes septated by folding and fusion of the anterior ventricular wall, trapping epicardium in its core. This folding septum develops as the horizontal septum in reptiles and the anterior part of the interventricular septum in the other taxa. The mechanism of folding is confirmed using DiI tattoos of the ventricular surface. Trapping of epicardium-derived cells is studied by transplanting embryonic quail pro-epicardial organ into chicken hosts. The effect of decreased epicardium involvement is studied in knock-out mice, and pro-epicardium ablated chicken, resulting in diminished and even absent septum formation. Proper folding followed by diminished ventricular fusion may explain the deep interventricular cleft observed in elephants. The vertical septum, although indistinct in most reptiles except in crocodilians and pythonidsis apparently homologous to the inlet septum. Eventually the various septal components merge to form the completely septated heart. In our attempt to discover homologies between the various septum components we aim to elucidate the evolution and development

  15. Tricuspid valve detachment in closure of congenital ventricular septal defect.

    PubMed

    Zhao, Jinping; Li, Jun; Wei, Xiang; Zhao, Bo; Sun, Wei

    2003-01-01

    From January 1991 through December 2001, 600 patients underwent closure of a perimembranous ventricular septal defect through a right atrial approach at our institution. In 122 of these patients, the operation included temporary detachment of a tricuspid valve septal leaflet from the annulus to allow complete visualization of a perimembranous ventricular septal defect The mean age of the patients at surgery was 4.6 years in those who underwent leaflet detachment and 4.7 years in the 478 patients who did not (P > 0.05). Preoperatively, all patients were in sinus rhythm. Echocardiography showed trivial tricuspid regurgitation in 21 of the patients undergoing detachment and in 39 of the non-detachment patients. There was no difference in bypass time or aortic cross-clamp time between the 2 groups. Postoperatively, 3 patients in the non-detachment group had heart block; all other patients were in sinus rhythm. Echocardiograms on the 7th postoperative day showed small residual ventricular septal defects in none of the patients who underwent valve detachment and in 10 of the non-detachment patients; mild tricuspid regurgitation was present in 12 non-detachment patients only; and trivial tricuspid regurgitation was present in 19 patients who underwent valve detachment and in 29 who did not. There was no hospital death in either group. Long-term follow-up showed no progression of tricuspid regurgitation or tricuspid stenosis. All patients remained in sinus rhythm. This study suggests that tricuspid valve detachment is a safe, effective technique that improves exposure for ventricular septal defect repair and does not adversely affect valve competence. PMID:12638669

  16. Heterogeneity of ventricular repolarization in newborns with severe aortic coarctation.

    PubMed

    Nigro, Gerardo; Russo, Vincenzo; Rago, Anna; Papa, Andrea Antonio; Cioppa, Nadia Della; Di Meo, Federica; Corcione, Antonio; Caianiello, Giuseppe; Russo, Maria Giovanna; Calabrò, Raffaele

    2012-02-01

    Sudden death is a possible occurrence for newborns younger than 1 year with severe aortic coarctation (CoA) before surgical correction. Basic research and animal experiments have shown electrophysiologic changes during mechanical ventricular pressure overload. The current study aimed to evaluate the effect of severe CoA on the heterogeneity of ventricular repolarization by examining corrected QT and JT interval dispersion (respectively, QTc-D and JTc-D) and electrocardiographic parameters of spatial heterogeneity of ventricular repolarization in newborns with no associated congenital cardiac malformations. The study enrolled 30 isolated severe CoA neonates (age, 45 ± 15 days; 17 males) with normal size and wall thickness of the left ventricle before surgical correction and 30 age- and sex-matched healthy newborns used as control subjects. Heart rate, QRS duration, maximum and minimum QT and JT intervals, and QTc-D and JTc-D measurements were performed. The healthy control group did not significantly differ from the CoA group in terms of heart rate, weight, height, and echocardiographic parameters. Compared with the healthy control group, the CoA group presented significantly increased values of QTc-D (109.7 ± 43.4 vs. 23 ± 15 ms; P = 0.03) and JTc-D (99.1 ± 43.3 vs. 65.8 ± 24.1 ms; P = 0.04). A statistically significant correlation was found between the Doppler peak pressure gradient across the coarctation site and the values of QTc-D (r = 0.48; P = 0.03) and JTc-D (r = 0.42; P = 0.04). Our study showed significantly increased QTc-D and JTc-D in isolated CoA newborns with normal left ventricular geometry. PMID:21968578

  17. Intraoperative bronchoscopic visualization of left ventricular assist device thrombus.

    PubMed

    Yost, Gardner; Bhat, Geetha; Modi, Sejal; Pappas, Pat; Tatooles, Antone

    2016-07-01

    Despite advancements in left ventricular assist device (LVAD) design and clinical management, device thrombosis remains a pertinent complication. Limited imaging makes precise visualization of clot location and shape very challenging. We report the usage of videobronchoscopic exploration of explanted LVADs for direct visualization of clot in two patients. This technique is a rapid and inexpensive means of improving our understanding of LVAD clot formation and may be useful in surgical exploration of inflow and outflow tracts during LVAD exchange. PMID:26452760

  18. Left ventricular synchronicity is impaired in patients with active acromegaly.

    PubMed

    Kırış, Abdulkadir; Erem, Cihangir; Turan, Oğuzhan Ekrem; Civan, Nadim; Kırış, Gülhanım; Nuhoğlu, Irfan; Ilter, Abdulselam; Ersöz, Halil Onder; Kutlu, Merih

    2013-08-01

    Acromegaly is associated with a variety of cardiovascular disturbances such as left ventricular hypertrophy, diastolic cardiac dysfunction, and hypertension. Left ventricular (LV) dyssynchrony means the impairment of synchronicity and is defined as the loss of the simultaneous peak contraction of corresponding cardiac segments. The objective of this study was to investigate whether acromegalic patients have left ventricular dyssynchrony. Dyssynchrony was evaluated in 30 patients with active acromegaly and 30 controls. All the patients and controls were subjected to a tissue synchronization imaging. The time to regional peak systolic tissue velocity (Ts) in LV by the six-basal-six-mid-segmental model was measured on ejection phase TSI images and four TSI parameters of systolic dyssynchrony were computed. All TSI parameters of LV dyssynchrony increased in patients with acromegaly compared to the controls: the standard deviation (SD) of the 12 LV segments Ts (43.5 ± 13.5 vs 26.2 ± 12.5, p < 0.001); the maximal difference in Ts between any 2 of the 12 LV segments (133.3 ± 38 vs 84.6 ± 37.6, p < 0.001); the SD of the 6 basal LV segments (41.1 ± 15.9 vs 25.4 ± 14.8, p = 0.001); and the maximal difference in Ts between any 2 of the 6 basal LV segments (102.6 ± 37.5 vs 65.2 ± 36.9, p = 0.001). In addition, there were significant relationships between the levels of growth hormone/insulin-like growth factor-1 and Ts-SD-12. LV synchronicity has been impaired in patients with acromegaly. Left ventricular dyssynchrony is associated with disease activity and it may contribute to the harmful cardiovascular effects of acromegaly.

  19. Synthetic Marijuana Induced Acute Nonischemic Left Ventricular Dysfunction

    PubMed Central

    Sriganesh, Priatharsini; Virparia, Vasudev; Patel, Falgun; Khanna, Ashok

    2016-01-01

    Synthetic marijuana is an uptrending designer drug currently widely spread in the US. We report a case of acute deterioration of nonischemic left ventricular dysfunction after exposure to synthetic marijuana. This case illustrates the importance of history taking in cardiac patients and identifies a negative cardiovascular effect of synthetic marijuana known as K2, not yet well detected by urine toxicology screening tools. PMID:27119030

  20. Multiple left ventricular aneurysms in a young female.

    PubMed

    Raval, Abhishek P; Shukla, Anand; Garg, Rajiv; Rana, Yashpal; Shah, Komal

    2016-02-01

    Multiple left ventricular aneurysms (LVAs) are rare, especially in a young female. A 29-year-old woman presented vague symptoms. Multiple LVAs were revealed and confirmed on different imaging modalities, including chest radiography, echocardiography, contrast ventriculography and cardiac magnetic resonance imaging. Detailed work-up for probable etiologies including ischemic, infectious, inflammatory and autoimmune causes was negative. In the absence of angina, decompensated congestive heart failure, arrhythmias and embolism, the patient was managed conservatively, with excellent mid-term outcome.

  1. Ventricular ejection force in growth-retarded fetuses.

    PubMed

    Rizzo, G; Capponi, A; Rinaldo, D; Arduini, D; Romanini, C

    1995-04-01

    The objective of this study was to determine whether in growth-retarded fetuses secondary to uteroplacental insufficiency the cardiac ventricles exert a force different from that of appropriately grown fetuses. Doppler echocardiographic studies were performed in 156 appropriately grown fetuses (gestational age 18-38 weeks) and in 72 growth-retarded fetuses (gestational age 24-36 weeks) free from structural and chromosomal abnormalities and characterized by Doppler changes in the umbilical artery and middle cerebral artery suggesting uteroplacental insufficiency as the most likely etiology of the growth defect. Right and left ventricular ejection force values were calculated from velocity waveforms recorded at the level of aortic and pulmonary valves, according to Newton's second law of motion. In appropriately grown fetuses, left and right ventricular ejection force values significantly increased with advancing gestation and the two ventricles exerted similar force. In growth-retarded fetuses, the ventricular ejection force was significantly and symmetrically decreased in both ventricles. Among growth-retarded fetuses, a poorer perinatal outcome was observed in those fetuses in which the ejection force of both ventricles was below the 5th centile of the normal limits for gestation. In 12 growth-retarded fetuses followed longitudinally during the last week preceding intrauterine death or Cesarean section due to antepartum heart-rate late decelerations, a significant decrease of ejection force was found in both ventricles. Finally, a significant relationship was found between the severity of acidosis and right and left ventricular ejection force values in 22 fetuses in which Doppler recordings were performed immediately before cordocentesis.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Factors affecting the accuracy of ventricular catheter placement.

    PubMed

    Wan, Kai Rui; Toy, Jennifer Ah; Wolfe, Rory; Danks, Andrew

    2011-04-01

    Despite technological improvements, ventriculoperitoneal (VP) shunts are still often complicated by malfunction, predominantly with proximal catheter obstruction. There is evidence that accurate placement of the ventricular catheter is significantly related to shunt survival. To identify possible risk factors that might lead to suboptimal shunt placement, we retrospectively reviewed the demographic data and radiological scans of 141 patients who underwent a VP shunt operation from 2005 to 2008 at our institution. We developed and validated a novel scale to assess catheter placement. Almost half (47.9%) of the catheters were "excellently" placed with the entire tip located in the cerebrospinal fluid, and the position of 25% was considered "good". However, 26.8% were less than optimally placed ("poor", "fair" or "moderate"), with 8.5% ("poor") lying entirely outside the ventricular system. Statistical analysis demonstrated that the preoperative size of the ventricles and the age of the patient at shunt insertion were the most important predictors in determining the quality of ventricular catheter placement. Further studies are required to evaluate frameless stereotaxy in optimizing shunt placement in patients with smaller ventricles.

  3. Modeling gender effects on electrical activity of single ventricular myocytes.

    PubMed

    Cieniawa, Jerzy; Baszak, Jacek; Olchowik, Grazyna; Widomska, Justyna

    2013-09-01

    In this study we investigate the mechanisms underlying gender differences in the generation of arrhythmias in the long QT and Brugada syndromes. Simulations were conducted at the single myocyte level using a detailed mathematical model of human ventricular myocytes. Given the scarce human data on the gender-related differences in single cardiac cells, we assumed gender-related differences in five ionic-current systems: fast sodium current (INa), slowly inactivating late sodium current (INal), transient outward potassium current (Ito), slow delayed rectifier potassium current (IKs), and calcium current through the L-type channel (ICa(L)), based on experimental results obtained in canine myocytes. Our modeling results suggest that in left ventricular myocytes, enhanced INal under conditions of reduced repolarization reserve results in sex-dependent development of early afterdepolarizations (EADs) in the post-pause action potentials (APs). Moreover, this modeling study demonstrates increased propensity for the development of the loss of the AP dome in male epicardial myocytes of the right ventricle compared with other types of myocytes from the left and right ventricles. Finally, we also found a slight effect of INal on gender-dependent loss of AP dome in epicardial right ventricular myocytes. In conclusion, at the cellular level, gender differences in the development of EADs and the propensity to develop the loss of the AP dome can be attributed to male/female related differences in INa, INal, Ito, IKs, and ICa(L). PMID:23726761

  4. [Exercise test and ventricular tachycardia: the French experience].

    PubMed

    Douard, H; Mora, B; Broustet, J P

    1987-03-01

    The incidence of severe ventricular arrhythmia requiring electric shock or prompt intravenous therapy was evaluated during or immediately after 458,000 exercise tests performed in 46 french centres between 1975 and 1985; 177,000 tests were performed exclusively in cardiac patients during supervised exercise training sessions. Sixty cases of severe arrhythmia (ventricular fibrillation 23, ventricular tachycardia 35, asystole 2) occurred (1/7600 tests). One or several electric shocks were necessary in 35 cases. Six patients died (1/76,333 tests), 2 of them during training sessions; 5 had phase II or III myocardial infarction, and the 6th patient had moderately tight valvular aortic stenosis. The five coronary patients were taking various anti-arrhythmic drugs. Among the 54 survivors, 14 were lost sight of and 4 died, 2 of these suddenly including one who passed away during a bicycle ride. All others are alive after a 3.25 +/- 2.9 years follow-up. The association of a multiple-vessel disease with an extensive fibrous plaque is a syndrome that is highly sensitive but fortunately little specific in predicting severe arrhythmia during exercise tests.

  5. Surgical Ventricular Septal Myectomy in the Developing World.

    PubMed

    Maron, Barry J; Spirito, Paolo

    2016-03-01

    Surgical septal myectomy is the preferred treatment strategy in hypertrophic cardiomyopathy (HC) to reverse progressive heart failure symptoms due to left ventricular outflow obstruction. However, open-heart surgery and the ventricular septal myectomy option in particular have limited accessibility in many parts of the world, including developing countries such as India, where skilled surgeons familiar with the complex left ventricular outflow tract anatomy of obstructive HC are rare. Indeed, septal myectomy, which is currently performed in only a limited number of countries, can become available in other venues if experienced surgeons dedicate their skills to this highly specialized but rewarding operation. Relevant to this issue, we describe a recent myectomy initiative in India (New Delhi) that demonstrates the possibility of generating a surgical myectomy program outside of an elite academic center environment, otherwise regarded as unfavorable for such an initiative. Demonstration that safe and effective septal myectomy is possible under such difficult circumstances bodes well for the expansion of this operation to many countries in the best interests of the hypertrophic cardiomyopathy patient population.

  6. IL-17A promotes ventricular remodeling after myocardial infarction.

    PubMed

    Zhou, Su-Feng; Yuan, Jing; Liao, Meng-Yang; Xia, Ni; Tang, Ting-Ting; Li, Jing-Jing; Jiao, Jiao; Dong, Wen-Yong; Nie, Shao-Fang; Zhu, Zheng-Feng; Zhang, Wen-Cai; Lv, Bing-Jie; Xiao, Hong; Wang, Qing; Tu, Xin; Liao, Yu-Hua; Shi, Guo-Ping; Cheng, Xiang

    2014-10-01

    Inflammatory responses play an important role in the pathogenesis of adverse ventricular remodeling after myocardial infarction (MI). We previously demonstrated that interleukin (IL)-17A plays a pathogenic role in myocardial ischemia/reperfusion injury and viral myocarditis. However, the role of IL-17A in post-MI remodeling and the related mechanisms have not been fully elucidated. Acute MI was induced by permanent ligation of the left anterior descending coronary artery in C57BL/6 mice. Repletion of IL-17A significantly aggravated both early- and late-phase ventricular remodeling, as demonstrated by increased infarct size, deteriorated cardiac function, increased myocardial fibrosis, and cardiomyocyte apoptosis. By contrast, genetic IL-17A deficiency had the opposite effect. Additional studies in vitro indicated that IL-17A induces neonatal cardiomyocyte (from C57BL/6 mice) apoptosis through the activation of p38, p53 phosphorylation, and Bax redistribution. These data demonstrate that IL-17A induces cardiomyocyte apoptosis through the p38 mitogen-activated protein kinase (MAPK)-p53-Bax signaling pathway and promotes both early- and late-phase post-MI ventricular remodeling. IL-17A might be an important target in preventing heart failure after MI. Key message: We demonstrated that IL-17A plays a pathogenic role both in the early and late stages of post-MI remodeling. IL-17A induces murine cardiomyocyte apoptosis. IL-17A induces murine cardiomyocyte apoptosis through the p38 MAPK-p53-Bax signaling pathway.

  7. Failure mechanisms of ventricular tissue due to deep penetration.

    PubMed

    Gasser, T Christian; Gudmundson, Peter; Dohr, Gottfried

    2009-03-26

    Lead perforation is a rare but serious complication of pacemaker implantations, and in the present study the associated tissue failure was investigated by means of in-vitro penetration of porcine and bovine ventricular tissue. Rectangular patches from the right ventricular free wall and the interventricular septum were separated, bi-axially stretched and immersed in physiological salt solution at 37( composite function)C before load displacement curves of in total 891 penetrations were recorded. To this end flat-bottomed cylindrical punches of different diameters were used, and following mechanical testing the penetration sites were histological analyzed using light and electron microscopes. Penetration pressure, i.e. penetration force divided by punch cross-sectional area decreased slightly from 2.27(SD 0.66) to 1.76(SD0.46)N/mm(2) for punches of 1.32 to 2.30 mm in diameter, respectively. Deep penetration formed cleavages aligned with the local fiber orientation of the tissue, and hence, a mode-I crack developed, where the crack faces were wedged open by the advancing punch. The performed study derived novel failure data from ventricular tissue due to deep penetration and uncovered associated failure mechanisms. This provides information to derive mechanical failure models, which are essential to enrich our current understanding of failure of soft biological tissues and to guide medical device development.

  8. Analysis of left ventricular impedance in comparison with ultrasound images.

    PubMed

    Choi, Seong Wook; Park, Sung Min

    2012-05-01

    Cardiac monitoring of ventricular assist devices (VADs) is important for detecting heart failure risks, such as critical arrhythmia and ventricular fibrillation, and for supplying data that are useful for hemodynamic control. Specifically, impedance cardiograms (ICGs) are especially beneficial because they have no effect on the tissue or organs and can monitor various parameters simultaneously, including the heart rate and heart contractions. In this article, we measured impedance changes in porcine left ventricles using electrodes placed around the inlet and outlet cannulae of the VAD. The measured left ventricular impedance (LVI) waveform changes are caused by heart movements, such as cardiac muscle contraction and changes in blood volume as a result of heart filling and emptying. In contrast to other impedance measurements, LVI is less affected by the movement of other organs. Using a porcine model, LVIs were measured and compared with blood flow data measured with an ultrasound blood flowmeter. The ICG showed the same frequency as the animal's heart rate, and their amplitudes were closely related to cardiac output (CO). However, the waveform differed from other vital signs, such as CO, electrocardiogram, and blood pressure. Ultrasound images were used to explain the impedance waveform. In the ultrasound images, we obtained the shape and size of the animal's heart and calculated the predicted impedance data. We then compared these to the actual measured data. These results show that the impedance signal contains detailed information on heart rate and CO; these results were unaffected by the cannulae or VAD perfusion. PMID:22188560

  9. Noninvasive evaluation of left ventricular function in chronic severe anemia.

    PubMed

    Singh, P I; Verma, K; Sood, S

    1989-03-01

    Left ventricular function was evaluated noninvasively in cases of chronic severe anemia (CSA) by recording systolic and diastolic time intervals (STI and DTI). These time intervals were recorded in 38 patients with CSA (hemoglobin below 7 g%), without cardiac decompensation, and in 30 control subjects. STI and DTI were measured from the simultaneous recordings of the apexcardiogram, carotid arterial pulse, electrocardiogram and phonocardiogram. The left ventricular ejection time was significantly prolonged (p less than 0.02), and associated with marked shortening of the PEP and reduction of the PEP/LVET ratio (p less than 0.001 in each case) in cases of CSA as compared to controls. Regarding the DTI, there was significant shortening of total filling time, slow filling time (p less than 0.001 in each case) and atrial systole (p less than 0.01) with no appreciable change in rapid filling time and isovolumic relaxation time. The SFT/RFT ratio and a/H ratio (the amplitude of the a-wave relative to the total height of the apexcardiogram) showed significant reductions (p less than 0.001 in each case). These changes in STI and DTI indicate enhanced left ventricular performance during diastole followed by faster and more complete relaxation during diastole in CSA.

  10. Cardioangiographic findings in patients with arrhythmogenic right ventricular dysplasia.

    PubMed Central

    Blomström-Lundqvist, C; Selin, K; Jonsson, R; Johansson, S R; Schlossman, D; Olsson, S B

    1988-01-01

    The dimension, contractility, and regional wall motion of the right and left ventricles were scored on the angiograms of 13 patients with arrhythmogenic right ventricular dysplasia. In 10 patients the right ventricle was enlarged, in eight the contractility of the right ventricle was reduced, and in all but one patient there were regional wall motion abnormalities of the right ventricle. The most common abnormality of regional wall motion was mild hypokinesia. There were bulging or dyskinetic areas in seven patients. Regional wall motion abnormalities of the left ventricle were found in five patients, two of whom also had bulging or dyskinetic areas. The reproducibility of right ventricular dimension, contractility, and regional wall motion scores was generally fair but varied unexpectedly both within and between two observers (Kendall's Tau 0.38-0.92). The score values of regional wall motion for some of the segments differed considerably within and between observers. One of the observers consistently gave higher scores than the other. These data suggest that a more objective approach is needed for evaluating angiographic changes in arrhythmogenic right ventricular dysplasia. Images Fig 2 Fig 3 Fig 4 Fig 5 PMID:3382567

  11. Ventricular and vascular stiffening in aging and hypertension.

    PubMed

    Faconti, L; Bruno, R M; Ghiadoni, L; Taddei, S; Virdis, A

    2015-01-01

    The assessment of arterial stiffness, a common feature of aging, exacerbated by pathological conditions like hypertension, has become an attractive tool for identifying structural and functional changes of the arteries even in an early stage of the atherosclerotic disease. Arterial stiffness has been recognized as an important physio-pathological determinant for the age-related rise in systolic blood pressure, demonstrating also an independent predictive value for cardiovascular events. In the recent decades, many techniques and indices to evaluate vascular stiffness have been developed and extensive data concerning their prognostic value have been collected. Moreover, it has become clear that vessel and heart must be considered as a unique system, in which combined stiffness of vessel and heart interacts to limit cardiovascular performance. In this review, main methods and indices used to estimate arterial and ventricular stiffness are presented, focusing on their alteration in physiological aging and arterial hypertension. Furthermore, the concept of ventricular-arterial coupling is explained in order to give an insight to the interplay between arterial and ventricular stiffness in aging and hypertension.

  12. Attempted entrainment of circus movement tachycardias by ventricular stimulation.

    PubMed

    Saoudi, N C; Castellanos, A; Zaman, L; Portillo, B; Schwartz, A; Myerburg, R J

    1986-01-01

    Entrainment was attempted while pacing the right ventricle in 12 patients with circus movement tachycardias. At the onset of stimulation eight patients had short episodes of intraventricular and atrioventricular dissociation during which the paced impulses activated the various ventricular recording sites (right and left), but did not reach the atria. The latter occurred because the ventricular electrograms were recorded from parts of the ventricles which were not essential components of the reentry circuit. Relatively long (greater than 5 s) runs of entrainment were not possible in any case because of the relatively prompt termination of the tachycardias. Whereas in three patients this was due to the abrupt appearance of retrograde block in the accessory pathway, in nine patients it happened when the sequential, anterograde and retrograde, penetration of the AV node resulted in AV nodal block of the subsequent, reentering atrial impulse. The findings in this study showed that, with the methodology used, entrainment of circus movement tachycardias by ventricular stimulation had to be defined conceptually, by the fulfillment of requirements which did not include its occurrence for at least 5 seconds. Furthermore, the results also suggested that entrainment and tachycardia termination were best demonstrated by a technique which allowed the emission of the first stimulus in a constant (late) moment of the cycle, with deliverance of one additional stimulus at the same cycle length in successive pacing runs.

  13. Robust left ventricular myocardium segmentation for multi-protocol MR

    NASA Astrophysics Data System (ADS)

    Groth, A.; Weese, J.; Lehmann, H.

    2012-02-01

    For a number of cardiac procedures like the treatments of ventricular tachycardia (VT), coronary artery disease (CAD) and heart failure (HF) both anatomical as well as vitality information about the left ventricular myocardium are required. To this end, two images for the anatomical and functional information, respectively, must be acquired and analyzed, e.g. using two different 3D MR protocols. To enable automatic analysis, a workflow has been proposed1 which allows to integrate the vitality information extracted from the functional image data into a patient-specific anatomical model generated from the anatomical image. However, in the proposed workflow the extraction of accurate vitality information from the functional image depends to a large extend on the accuracy of both the anatomical model and the mapping of the model to the functional image. In this paper we propose and evaluate methods for improving these two aspects. More specifically, on one hand we aim to improve the segmentation of the often low-contrast left ventricular epicardium in the anatomical 3D MR images by introducing a patient-specific shape-bias. On the other hand, we introduce a registration approach that facilitates the mapping of the anatomical model to images acquired by different protocols and modalities, such as functional 3D MR. The new methods are evaluated on clinical MR data, for which considerable improvements can be achieved.

  14. Spirals in the Heart Muscle- From Ventricular Tachycardia to Fibrillation

    NASA Astrophysics Data System (ADS)

    Karma, Alain

    1997-03-01

    Ventricular fibrillation (VF) is an often fatal cardiac arrhythmia. It is associated with the sudden onset of a spatiotemporally disorganised electrical wave activity that destroys the main pumping function of the ventricular muscle. In a healthy heart, VF is preceded by a brief period of ventricular tachycardia (VT), a rapid contraction of the heart muscle which decays into VF in a few seconds. Over the last few years, experiments and theoretical models have converged on the idea that the propagation of a single spiral wave of electrical activity (analogous to spirals found in other excitable media such as the Belousov-Zhabotinsky reaction) is responsible for VT, and that several spirals moving across the heart surface are responsible for VF. Yet, there is still no clear picture of how VT degenerates into VF after being initiated by a premature stimulus. Results of numerical simulations of wave propagation in two and three-dimensional cardiac tissue that identify two important factors in the transition from VT to VF will be presented. The first is the action potential restitution property of cardiac cells that leads to spiral wave instabilities. The second is the twist of the fiber axis that leads to the breakup of scroll wave filaments (i.e. the three-dimensional analog of spiral waves) above a critical muscle thickness.

  15. Increased Ventricular Cerebrospinal Fluid Lactate in Depressed Adolescents

    PubMed Central

    Bradley, Kailyn A. L.; Mao, Xiangling; Case, Julia A. C.; Kang, Guoxin; Shungu, Dikoma C.; Gabbay, Vilma

    2016-01-01

    Background Mitochondrial dysfunction has been increasingly examined as a potential pathogenic event in psychiatric disorders, although its role early in the course of major depressive disorder (MDD) is unclear. Therefore, the purpose of this study was to investigate mitochondrial dysfunction in medication-free adolescents with MDD through in vivo measurements of neurometabolites using high-spatial resolution multislice/multivoxel proton magnetic resonance spectroscopy. Methods Twenty-three adolescents with MDD and 29 healthy controls, ages 12–20, were scanned at 3T and concentrations of ventricular cerebrospinal fluid lactate, as well as N-acetyl-aspartate (NAA), total creatine (tCr), and total choline (tCho) in the bilateral caudate, putamen, and thalamus were reported. Results Adolescents with MDD exhibited increased ventricular lactate compared to healthy controls [F(1, 41) = 6.98, p = .01]. However, there were no group differences in the other neurometabolites. Dimensional analyses in the depressed group showed no relation between any of the neurometabolites and symptomatology, including anhedonia and fatigue. Conclusions Increased ventricular lactate in depressed adolescents suggests mitochondrial dysfunction may be present early in the course of MDD; however it is still not known whether the presence of mitochondrial dysfunction is a trait vulnerability of individuals predisposed to psychopathology or a state feature of the disorder. Therefore, there is a need for larger multimodal studies to clarify these chemical findings in the context of network function. PMID:26802978

  16. Focal gap junction uncoupling and spontaneous ventricular ectopy.

    PubMed

    Gutstein, David E; Danik, Stephan B; Lewitton, Steve; France, David; Liu, Fangyu; Chen, Franklin L; Zhang, Jie; Ghodsi, Newsha; Morley, Gregory E; Fishman, Glenn I

    2005-09-01

    Genetic studies in the mouse have demonstrated that conditional cardiac-restricted loss of connexin43 (Cx43), the major ventricular gap junction protein, is highly arrhythmogenic. However, whether more focal gap junction remodeling, as is commonly seen in acquired cardiomyopathies, influences the propensity for arrhythmogenesis is not known. We examined electrophysiological properties and the frequency of spontaneous and inducible arrhythmias in genetically engineered chimeric mice derived from injection of Cx43-deficient embryonic stem cells into wild-type recipient blastocysts. Chimeric mice had numerous well-circumscribed microscopic Cx43-negative foci in their hearts, comprising approximately 15% of the total surface area as determined by immunohistochemical analysis. Systolic function in the chimeric mice was significantly depressed as measured echocardiographically (19.0% decline in fractional shortening compared with controls, P < 0.05) and by invasive hemodynamics (17.6% reduction in change of pressure over time, P < 0.01). Chimeras had significantly more spontaneous arrhythmic events than controls (P < 0.01), including frequent runs of nonsustained ventricular tachycardia in some of the chimeric mice. However, in contrast to mice with conditional cardiac-resricted loss of Cx43 in the heart, no sustained ventricular tachyarrhythmias were observed. We conclude that focal areas of uncoupling in the myocardium increase the likelihood of arrhythmic triggers, but more widespread uncoupling is required to support sustained arrhythmias. PMID:15894579

  17. Focal gap junction uncoupling and spontaneous ventricular ectopy

    PubMed Central

    Gutstein, David E.; Danik, Stephan B.; Lewitton, Steve; France, David; Liu, Fangyu; Chen, Franklin L.; Zhang, Jie; Ghodsi, Newsha; Morley, Gregory E.; Fishman, Glenn I.

    2009-01-01

    Genetic studies in the mouse have demonstrated that conditional cardiac-restricted loss of connexin43 (Cx43), the major ventricular gap junction protein, is highly arrhythmogenic. However, whether more focal gap junction remodeling, as is commonly seen in acquired cardiomyopathies, influences the propensity for arrhythmogenesis is not known. We examined electrophysiological properties and the frequency of spontaneous and inducible arrhythmias in genetically engineered chimeric mice derived from injection of Cx43-deficient embryonic stem cells into wild-type recipient blastocysts. Chimeric mice had numerous well-circumscribed microscopic Cx43-negative foci in their hearts, comprising ~15% of the total surface area as determined by immunohistochemical analysis. Systolic function in the chimeric mice was significantly depressed as measured echocardiographically (19.0% decline in fractional shortening compared with controls, P < 0.05) and by invasive hemodynamics (17.6% reduction in change of pressure over time, P < 0.01). Chimeras had significantly more spontaneous arrhythmic events than controls (P < 0.01), including frequent runs of nonsustained ventricular tachycardia in some of the chimeric mice. However, in contrast to mice with conditional cardiac-resticted loss of Cx43 in the heart, no sustained ventricular tachyarrhythmias were observed. We conclude that focal areas of uncoupling in the myocardium increase the likelihood of arrhythmic triggers, but more widespread uncoupling is required to support sustained arrhythmias. PMID:15894579

  18. The Wedensky test predicts malignant ventricular arrhythmias after myocardial infarction

    PubMed Central

    2013-01-01

    Objectives. Better tools are needed for detection of future malignant ventricular arrhythmias post myocardial infarct (MI). Wedensky Modulation (WM) is a new semi-invasive method: A short low-amplitude electrical impulse is applied synchronized to the QRS between a precordial and dorsal thoracic patch, and changes in the following QRS-T are registered. Design. A total of 357 (MI) ICD patients underwent WM testing. QRS-T wavelet analysis provided WM Indexes for the QRS complex (WMI-R) and T wave (WMI-T). Outcome was the time to first occurrence of appropriate device therapy for ventricular arrhythmia. Patients were followed at 6-month intervals for 2 years. Results. No arrhythmia was induced by the testing. Two-year appropriate arrhythmia treatment occurred in 35% (WMI-R positive) versus 25% (WMI-R negative, p = 0.014), and. 45% versus 26% (p = 0.001) for WMI-T positive versus negative. Two-year event rates of WMI-R or WMI-T positive versus WMI-R and WMI-T negative were 36% versus 22% (p = 0.004). In Cox proportional hazard model, the combination of WMI-R and WMI-T was the only statistically significant event predictor (p = 0.003). Conclusion. Potentially life-threatening ventricular arrhythmic events could be predicted by the WM test. In combination with other risk factors WMI may be useful in these patients. PMID:24050376

  19. Two Types of Calcium Channels in Guinea Pig Ventricular Myocytes

    NASA Astrophysics Data System (ADS)

    Mitra, Raman; Morad, Martin

    1986-07-01

    In cardiac muscle, Ca2+ plays a key role in regulation of numerous processes, including generation of the action potential and development of tension. The entry of Ca2+ into the cell is regulated primarily by voltage-gated channels in the membrane. Until recently, it was felt that only one type of Ca2+ channel existed in cardiac ventricular muscle. Experiments reported here suggest that in isolated guinea pig ventricular myocytes, there are two distinct types of Ca2+ channels with markedly different activation thresholds, inactivation kinetics, and sensitivities to inorganic and organic Ca2+ channel blockers. The channels were also distinguished based on their response to increased frequency of clamping such that the current through the low-threshold channel decreased while that through the high-threshold channel increased. In a few cells, the current through both channels was enhanced by isoproterenol, a β -adrenergic agonist, but only the high-threshold channel was enhanced by the Ca2+-channel agonist Bay K 8644. Thus, isolated guinea pig ventricular myocytes appear to have two types of Ca2+ channels distinguished by various criteria.

  20. Dioxin (TCDD) enhances triggered-afterdepolarizations in rat ventricular myocytes

    PubMed Central

    Xie, An; Walker, Nigel J.; Wang, Desuo

    2007-01-01

    The effects of TCDD (2,3,7,8-Tetrachlorodibenzo-p-dioxin) on action potential and afterdepolarizations were studied in rat ventricular myocytes using nystatin-perforated whole-cell patch-clamp technique. TCDD treatment, in the concentration range of 1 to 100 nM, significantly prolonged action potential duration measured at 90% of repolarization (APD90). The triggered delayed-afterdepolarizations (DADs) was observed in 6 out of 8 cells after exposure of TCDD (10 nM). In the presence of isoproterenol (ISO, 10 nM) or Bay K 8644 (1 μM), TCDD (10 nM) markedly augmented the amplitude and frequency of the arrhythmogenic DADs and triggered sustained spontaneous firings in ventricular myocytes. Voltage-clamp data indicated that TCDD (10 nM) exposure significantly enhanced the transient inward current (Iti). The triggered early-afterdepolarizations (EADs) were evoked only in cells simultaneously exposed to TCDD (10 nM) and ISO (or Bay K 8644). Further study indicated that TCDD treatment increased L-type Ca2+ current. These results indicate that activation of TCDD signaling pathway can prolong action potential duration and cause abnormal triggered afterdepolarizations. These effects may lead to clinically relevant ventricular arrhythmia especially when susceptible individuals are under elevated sympathetic stress or suffering from other myocardiopathies coincided with Ca2+-overload. PMID:17303918

  1. Estimation of left ventricular mass in conscious dogs.

    PubMed

    Coleman, B; Cothran, L N; Ison-Franklin, E L; Hawthorne, E W

    1986-12-01

    The short-axis area-length method for the estimation of left ventricular mass (LVM) and volume was validated in 24 formaldehyde-fixed canine hearts, using the truncated ellipsoid model. Estimates of the short-axis muscle area were highly correlated with directly measured values (R = 0.92; P less than 0.001). Similarly, LVM calculated using the area-length method showed good correlation with the actual weight of the left ventricle (LVW) (R = 0.85; P less than 0.001). When the regression equation was used, retrospectively, to correct the LVM estimates, the correlation between the actual LVW and the calculated LVM was markedly improved (R = 0.96; P less than 0.001). In awake dogs instrumented for measuring transverse and long axis ventricular dimensions using sonomicrometry, short-axis two-dimensional echocardiograms were used to convert the sonar external transverse dimensions to true diameters. The combined use of the corrected diameters and the regression equation to calculate LVM in the intact dog resulted in values that were highly correlated with the actual LVW (R = 0.95; P less than 0.001). Application of this technique for monitoring LVM in awake instrumented dogs demonstrated the method to be reproducible from day to day and to be sensitive enough to detect serial changes in mass such as during the development of left ventricular hypertrophy.

  2. Right Ventricular Hemodynamics in Patients with Pulmonary Hypertension

    NASA Astrophysics Data System (ADS)

    Browning, James; Fenster, Brett; Hertzberg, Jean; Schroeder, Joyce

    2012-11-01

    Recent advances in cardiac magnetic resonance imaging (CMR) have allowed for characterization of blood flow in the right ventricle (RV), including calculation of vorticity and circulation, and qualitative visual assessment of coherent flow patterns. In this study, we investigate qualitative and quantitative differences in right ventricular hemodynamics between subjects with pulmonary hypertension (PH) and normal controls. Fifteen (15) PH subjects and 10 age-matched controls underwent same day 3D time resolved CMR and echocardiography. Echocardiography was used to determine right ventricular diastolic function as well as pulmonary artery systolic pressure (PASP). Velocity vectors, vorticity vectors, and streamlines in the RV were visualized in Paraview and total RV Early (E) and Atrial (A) wave diastolic vorticity was quantified. Visualizations of blood flow in the RV are presented for PH and normal subjects. The hypothesis that PH subjects exhibit different RV vorticity levels than normals during diastole is tested and the relationship between RV vorticity and PASP is explored. The mechanics of RV vortex formation are discussed within the context of pulmonary arterial pressure and right ventricular diastolic function coincident with PH.

  3. A unified theory of calcium alternans in ventricular myocytes

    PubMed Central

    Qu, Zhilin; Liu, Michael B.; Nivala, Michael

    2016-01-01

    Intracellular calcium (Ca2+) alternans is a dynamical phenomenon in ventricular myocytes, which is linked to the genesis of lethal arrhythmias. Iterated map models of intracellular Ca2+ cycling dynamics in ventricular myocytes under periodic pacing have been developed to study the mechanisms of Ca2+ alternans. Two mechanisms of Ca2+ alternans have been demonstrated in these models: one relies mainly on fractional sarcoplasmic reticulum Ca2+ release and uptake, and the other on refractoriness and other properties of Ca2+ sparks. Each of the two mechanisms can partially explain the experimental observations, but both have their inconsistencies with the experimental results. Here we developed an iterated map model that is composed of two coupled iterated maps, which unifies the two mechanisms into a single cohesive mathematical framework. The unified theory can consistently explain the seemingly contradictory experimental observations and shows that the two mechanisms work synergistically to promote Ca2+ alternans. Predictions of the theory were examined in a physiologically-detailed spatial Ca2+ cycling model of ventricular myocytes. PMID:27762397

  4. Accelerated speciation in colour-polymorphic birds.

    PubMed

    Hugall, Andrew F; Stuart-Fox, Devi

    2012-05-09

    Colour polymorphism exemplifies extreme morphological diversity within populations. It is taxonomically widespread but generally rare. Theory suggests that where colour polymorphism does occur, processes generating and maintaining it can promote speciation but the generality of this claim is unclear. Here we confirm, using species-level molecular phylogenies for five families of non-passerine birds, that colour polymorphism is associated with accelerated speciation rates in the three groups in which polymorphism is most prevalent. In all five groups, colour polymorphism is lost at a significantly greater rate than it is gained. Thus, the general rarity and phylogenetic dispersion of colour polymorphism is accounted for by a combination of higher speciation rate and higher transition rate from polymorphism to monomorphism, consistent with theoretical models where speciation is driven by fixation of one or more morphs. This is corroborated by evidence from a species-level molecular phylogeny of passerines, incorporating 4,128 (66.5%) extant species, that polymorphic species tend to be younger than monomorphic species. Our results provide empirical support for the general proposition, dating from classical evolutionary theory, that colour polymorphism can increase speciation rates.

  5. CYP11B2 gene polymorphism among coronary heart disease patients and blood donors in Malaysia.

    PubMed

    Normaznah, Y; Azizah, M R; Kuak, S H; Rosli, M A

    2015-04-01

    Various previous studies have reported the implication of CYP11B2 gene polymorphism in the pathophysiology of cardiovascular diseases. In particular, the -344T/C polymorphism, which is located at a putative binding site for the steroidogenic transcription factor (SF-1) has been associated with essential hypertension, left ventricular dilation and coronary heart disease. In the present study, we aim to determine the allele and genotype frequencies of the CYP11B2 gene in patients with clinical manifestation of coronary heart disease and confirmed by angiography and blood donors and to calculate the association of the gene polymorphism with CHD. A total of 79 DNA from patients with coronary heart disease admitted to the National Heart Institute and 84 healthy blood donors have been genotyped using polymerase chain reaction technique followed by restriction enzyme digestion (RFLP). Results of the study demonstrated that out of 79 for the patients, 40 were homozygous T, 10 were homozygous C and 29 were heterozygous TC. The frequencies of genotype TT, CC and TC for patients were 0.5, 0.13 and 0.36 respectively. The frequencies of allele T and C in patients were 0.68 and 0.31 respectively. While for the blood donors, 40 subjects were of homozygous T, 7 were homozygous C and 37 were heterozygous TC. The genotype frequencies for the TT, CC and TC were 0.47, 0.08 and 0.44 respectively. The frequency of the allele T was 0.69 and allele C was 0.3. Chi-Square analysis showed that there was no significant difference in the genotype and C allele frequencies between the CHD patients and the blood donors. Our study suggests that there is lack of association between -344T/C polymorphism of CYP11B2 gene and coronary heart disease.

  6. Right ventricular free wall dissection as a rupture tract in left ventricular rupture during acute myocardial infarction.

    PubMed

    Takada, Aya; Saito, Kazuyuki; Murai, Tatsuya; Kurosaki, Kunihiko; Kurihara, Katsuyoshi; Hamamatsu, Akihiko

    2015-11-01

    Three rare cases of cardiac rupture with right ventricular wall dissection during acute myocardial infarction (AMI) were reported. The cases comprised 2% among our 148 previously reported postinfarction cardiac ruptures with sudden death. The dissections occurred in hearts with biventricular inferior wall AMI and developed between the superficial layers and the deeper layers of inferior wall of the right ventricle. All had an endocardial tear at the basal septum where it meets the inferior free wall of the left ventricle, and had an epicardial tear on the middle inferior wall of the right ventricle. Based on the evidence of the ages of the thrombi of the rupture tracts, delayed epicardial rupture was found besides that soon after the right ventricular dissection. PMID:26594003

  7. Upregulation of Soluble HLA-G in Chronic Left Ventricular Systolic Dysfunction

    PubMed Central

    Olesen, Line Lisbeth

    2016-01-01

    Left ventricular systolic dysfunction (LVSD) defined by ejection fraction (EF) <40% is common, serious but treatable, and correct diagnosis is the cornerstone of effective treatment. Biomarkers may help to diagnose LVSD and give insight into the pathophysiology. The immune system is activated in LVSD, and the immunomodulatory molecule human leukocyte antigen-G (HLA-G) may be involved. The primary aim was to measure soluble HLA-G (sHLA-G) in the blood in different stages of LVSD (<30% and 30–40%), in the midrange EF 40–50%, and in preserved EF ≥ 50% and to validate sHLA-G as a LVSD biomarker. The secondary aim was to examine associations between HLA-G gene polymorphisms influencing expression levels and LVSD. The 260 study participants were ≥75 years old, many with risk factors for heart disease or with known heart disease. Soluble HLA-G was significantly and uniformly higher in the groups with EF < 50% (<30, 30–40, and 40–50%) compared to EF > 50% (p < 0.0001). N-terminal fragment-pro-B-type natriuretic peptide (NT-proBNP) and uric acid values were inversely related to EF. According to Receiver Operating Characteristic (ROC) curves NT-proBNP outperformed both sHLA-G and uric acid as biomarkers of LVSD. Soluble HLA-G in blood plasma was elevated in LVSD regardless of EF. A novel finding was that a combined 14 bp ins-del/+3142 SNP HLA-G haplotype was associated with EF < 40%. PMID:27800497

  8. Failure of aneurysmectomy to improve left ventricular function.

    PubMed Central

    Sesto, M; Schwarz, F; Thiedemann, K U; Flameng, W; Schlepper, M

    1979-01-01

    Biplane left ventricular angiography was performed in 22 patients with isolated obstructive disease of the anterior descending branch of the left coronary artery and with an anterior aneurysm following transmural myocardial infarction. Six patients were restudied between 6 and 10 months after aneurysmectomy. Left ventricular reserve was estimated by analysis of a spontaneous postextrasystolic beat. Using angiographic techniques a contractile section, a transitional section, and a noncontractile section were identified. From the surgical patients the excised aneurysm and a transmural needle biopsy of the transitional section were investigated by light microscopy. With increasing volumes of noncontractile and transitional sections, total end-diastolic volume (r = 0.81, P less than 0.001) and end-systolic volume (r = 0.94, P less than 0.001) increased linearly, while the ejection fraction decreased (r = 0.70, P less than 0.001). No relation was found between the combined volumes of the noncontractile and transitional sections on the one hand, and the end-diastolic volume, the end-systolic volume, or the ejection fraction of the contractile section on the other hand. After aneurysmectomy a significant decrease was found in end-diastolic volume (194 to 133 ml/m2, P less than 0.001) and end-systolic volume (124 to 83 ml/m2, P less than 0.001) but no change occurred in ejection fraction (35 to 37%) and left ventricular end-diastolic pressure (23 to 25 mmHg). Surgical resection included part of the transitional section, which before surgery had an average ejection fraction of 27 per cent during a normal beat, rising to 41 per cent in a postextrasystolic beat. The transitional section after surgery now formed a large akinetic area of the anterior wall. We conclude that aneurysmectomy in isolated left anterior descending artery disease with anterior aneurysm fails to improve left ventricular function because the effect of reduction of left ventricular volumes is offset by

  9. Left ventricular aneurysm repair with use of a bovine pericardial patch.

    PubMed

    Henry, Matthew J; Preventza, Ourania; Cooley, Denton A; de la Cruz, Kim I; Coselli, Joseph S

    2014-08-01

    Left ventricular aneurysm, which can impair systolic function, has a reported incidence of 10% to 35% in patients after myocardial infarction. In a 58-year-old woman who had a history of myocardial infarction, we excised a large left ventricular aneurysm and restored left ventricular geometry with use of a bovine pericardial patch. The aneurysm's characteristics and the patient's preoperative left ventricular ejection fraction of 0.25 had indicated surgical intervention. The patient had an uneventful postoperative course, and her left ventricular ejection fraction was 0.50 to 0.55 on the 4th postoperative day. This case illustrates the value of surgical treatment for patients who have a debilitating left ventricular aneurysm.

  10. Noncompaction of the Ventricular Myocardium and Polycystic Kidney Disease: A Case Report.

    PubMed

    Fukino, Keiko; Ishiwata, Junpei; Shinohara, Hiroki; Oshima, Tsukasa; Kozaki, Tsunashi; Ikutomi, Masayasu; Amaki, Toshihiro; Nakamura, Fumitaka

    2016-06-01

    Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common hereditary disorders, characterized by the formation of multiple cysts in the kidneys and other organs, as well as noncystic manifestations such as cerebral aneurysm. The most common cardiovascular disorders associated with ADPKD include valvular abnormalities and aortic aneurysm. An association between ADPKD and impaired left ventricular function has occasionally been reported. We describe a 74-year-old woman with ADPKD and exertional dyspnea. Impaired left ventricular function resulting from noncompaction of the ventricular myocardium (NVM) and secondary left ventricular aneurysm were diagnosed. Cardiac sarcoidosis and ischemic heart disease were ruled out. Myocardial ischemia resulting from NVM was the presumptive cause of the ventricular aneurysm. To our knowledge, this is the first report of concurrent isolated NVM and left ventricular aneurysm in a patient with ADPKD. ADPKD and various cardiomyopathies, including NVM, are all reported to involve mutations of sarcomere genes, suggesting a possible link between the conditions. PMID:26873255

  11. Parasitic polymorphism of Coccidioides spp

    PubMed Central

    2014-01-01

    Background Coccidioides spp. is the ethiological agent of coccidioidomycosis, an infection that can be fatal. Its diagnosis is complicated, due to that it shares clinical and histopathological characteristics with other pulmonary mycoses. Coccidioides spp. is a dimorphic fungus and, in its saprobic phase, grows as a mycelium, forming a large amount of arthroconidia. In susceptible persons, arthroconidia induce dimorphic changes into spherules/endospores, a typical parasitic form of Coccidioides spp. In addition, the diversity of mycelial parasitic forms has been observed in clinical specimens; they are scarcely known and produce errors in diagnosis. Methods We presented a retrospective study of images from specimens of smears with 15% potassium hydroxide, cytology, and tissue biopsies of a histopathologic collection from patients with coccidioidomycosis seen at a tertiary-care hospital in Mexico City. Results The parasitic polymorphism of Coccidioides spp. observed in the clinical specimens was as follows: i) spherules/endospores in different maturation stages; ii) pleomorphic cells (septate hyphae, hyphae composed of ovoid and spherical cells, and arthroconidia), and iii) fungal ball formation (mycelia with septate hyphae and arthroconidia). Conclusions The parasitic polymorphism of Coccidioides spp. includes the following: spherules/endospores, arthroconidia, and different forms of mycelia. This knowledge is important for the accurate diagnosis of coccidioidomycosis. In earlier studies, we proposed the integration of this diversity of forms in the Coccidioides spp. parasitic cycle. The microhabitat surrounding the fungus into the host would favor the parasitic polymorphism of this fungus, and this environment may assist in the evolution toward parasitism of Coccidioides spp. PMID:24750998

  12. Long-term results of complex left ventricular reconstruction surgery: case report.

    PubMed

    Letsou, George V; Forrester, Matthew; Frazier, O H

    2011-01-01

    Left ventricular reconstruction is advocated as a surgical option for patients with severe congestive heart failure. Despite initial enthusiasm for this procedure, reports of long-term results are sparse. Herein, we describe a particularly gratifying case of left ventricular reconstruction in a 43-year-old man, who continues to have excellent left ventricular function 10 years postoperatively. This approach may be a reasonable alternative to cardiac transplantation in patients who lack other treatment options.

  13. Surgical Repair of an Aortico-Left Ventricular Tunnel with Acute Infective Endocarditis

    PubMed Central

    Xu, Sheng-song; Sha, Ji-ming; Xie, Xiang

    2014-01-01

    Aortic-left ventricular tunnel is a rare congenital cardiac anomaly, which always arises from the right coronary sinus and enters the left ventricle, occasionally the right ventricle and right atrium. However, aortic and left ventricular tunnel associated with infective endocarditis is rarely seen in literatures. Here, we present a case of aortic and left ventricular tunnel associated with infective endocarditis in a 47-year-old man. PMID:24429691

  14. Modeling ventricular interaction: a multiscale approach from sarcomere mechanics to cardiovascular system hemodynamics.

    PubMed

    Lumens, Joost; Delhaas, Tammo; Kirn, Borut; Arts, Theo

    2008-01-01

    Direct ventricular interaction via the interventricular septum plays an important role in ventricular hemodynamics and mechanics. A large amount of experimental data demonstrates that left and right ventricular pump mechanics influence each other and that septal geometry and motion depend on transmural pressure. We present a lumped model of ventricular mechanics consisting of three wall segments that are coupled on the basis of balance laws stating mechanical equilibrium at the intersection of the three walls. The input consists of left and right ventricular volumes and an estimate of septal wall geometry. Wall segment geometry is expressed as area and curvature and is related to sarcomere extension. With constitutive equations of the sarcomere, myofiber stress is calculated. The force exerted by each wall segment on the intersection, as a result of wall tension, is derived from myofiber stress. Finally, septal geometry and ventricular pressures are solved by achieving balance of forces. We implemented this ventricular module in a lumped model of the closed-loop cardiovascular system (CircAdapt model) The resulting multiscale model enables dynamic simulation of myofiber mechanics, ventricular cavity mechanics, and cardiovascular system hemodynamics. The model was tested by performing simulations with synchronous and asynchronous mechanical activation of the wall segments. The simulated results of ventricular mechanics and hemodynamics were compared with experimental data obtained before and after acute induction of left bundle branch block (LBBB) in dogs. The changes in simulated ventricular mechanics and septal motion as a result of the introduction of mechanical asynchrony were very similar to those measured in the animal experiments. In conclusion, the module presented describes ventricular mechanics including direct ventricular interaction realistically and thereby extends the physiological application range of the CircAdapt model.

  15. Sarcoma obstructing right ventricular cavity: clinical, echocardiographic, haemodynamic and angiographic features.

    PubMed Central

    Malcolm, A. D.; Shiu, M. F.; Jenkins, B. S.

    1979-01-01

    Right atrial hypertension and pericardial effusion developed 2 years after mastectomy for fibrosarcoma. Clinical and echocardiographic features suggested right ventricular tumour. At catheterization the right ventricular cavity was almost obliterated, with an infundibular gradient of 13 mmHg, and biopsy of the mass was attempted. Post-mortem revealed extensive infiltrating and intracavitary right ventricular fibrosarcoma without extracardiac tumour. Images Fig. 1 Fig. 2 Fig. 3 PMID:461285

  16. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?

    PubMed

    Tan, Alex Y; Ellenbogen, Kenneth

    2016-09-01

    Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia. PMID:27521094

  17. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?

    PubMed

    Tan, Alex Y; Ellenbogen, Kenneth

    2016-09-01

    Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia.

  18. Peripheral venous scintillation angiocardiography in determination of left ventricular volume in man.

    NASA Technical Reports Server (NTRS)

    Sullivan, R. W.; Bergeron, D. A.; Vetter, W. R.; Hyatt, K. H.; Haughton, V.; Vogel, J. M.

    1971-01-01

    Left ventricular end-diastolic volume was determined by cardiac visualization after peripheral venous injection of a gamma-emitting isotope in 10 patients with organic heart disease. The left ventricular end-diastolic volume measured by the isotope method consistently averaged 9% less than that determined by the X-ray method. The mean difference in left ventricular end-diastolic volume was 21 ml. Excellent correlation between the two methods was observed. It is pointed out that peripheral venous scintillation angiocardiography compares well with left ventriculography in the determination of left ventricular end-diastolic volume in man.

  19. [Competitive pacing in a patient with DDD pacemaker and bigeminal ventricular extrasystoles].

    PubMed

    Carbone, Vincenzo; Candelmo, Fiore; Todaro, Chiara; Oreto, Giuseppe

    2008-11-01

    The ECG recorded from a patient with DDD pacemaker showed variable responses of the pacing system to bigeminal ventricular extrasystoles, dependent on the coupling interval of premature beats. For relatively short coupling intervals, the premature spontaneous event was detected by the pacemaker, inhibiting both atrial and ventricular output, and resulting in a relatively long pacing pause. In slightly less premature end-diastolic extrasystoles, in contrast, the pacing system delivered an atrial spike that was superimposed upon the spontaneous premature QRS complex (pseudo-pseudofusion); under these circumstances, the atrial spike was followed, at the end of the programmed atrioventricular interval, by a ventricular spike falling on the extrasystolic T wave apex (competitive ventricular pacing). This phenomenon, however, did not express a sensing malfunction, but was due to post-atrial ventricular blanking (PAVB), a short period initiated by the atrial spike during which ventricular sensing is temporarily disabled, so that no signal can be detected. Finally, whenever premature end-diastolic impulses occurred after PAVB, during the brief interval defined ventricular safety pacing, the spontaneous event was sensed, being followed by an earlier-than-expected ventricular spike, whose prematurity was aimed at avoiding the occurrence of an artificial impulse upon the T wave of extrasystole. In conclusion, despite several not sensed ventricular extrasystoles and competitive pacing, no sensing malfunction was present. This case demonstrates how complex can be the electrocardiographic analysis of a DDD pacemaker, owing to the many complicating phenomena related to this pacing mechanism.

  20. Recurrent ventricular fibrillation under sufficient medical treatment in patient with coronary artery spasm

    PubMed Central

    Hiki, Masaru; Tokano, Takashi; Nakazato, Yuji; Daida, Hiroyuki

    2013-01-01

    In cases of coronary artery spasm, life-threatening ventricular arrhythmias are possible and can lead to sudden cardiac death. Treatment for this condition includes implantable cardioverter defibrillators, but their effectiveness in patients who present with ventricular fibrillation is debated. Our patient presented with intractable ventricular fibrillation episodes that triggered shocks from her implanted defibrillator. At 2 years of follow-up, we placed her on 200 mg/day of oral amiodarone, after identifying short-coupled premature contractions as the trigger for the ventricular fibrillation. In the 2 years following initiation of this drug therapy, the patient had no further fibrillation episodes. PMID:23821622

  1. Recurrent ventricular fibrillation under sufficient medical treatment in patient with coronary artery spasm.

    PubMed

    Hiki, Masaru; Tokano, Takashi; Nakazato, Yuji; Daida, Hiroyuki

    2013-07-02

    In cases of coronary artery spasm, life-threatening ventricular arrhythmias are possible and can lead to sudden cardiac death. Treatment for this condition includes implantable cardioverter defibrillators, but their effectiveness in patients who present with ventricular fibrillation is debated. Our patient presented with intractable ventricular fibrillation episodes that triggered shocks from her implanted defibrillator. At 2 years of follow-up, we placed her on 200 mg/day of oral amiodarone, after identifying short-coupled premature contractions as the trigger for the ventricular fibrillation. In the 2 years following initiation of this drug therapy, the patient had no further fibrillation episodes.

  2. Left ventricular assist device in the management of refractory electrical storm.

    PubMed

    Pourdjabbar, A; Maze, R; Hibbert, B; Ruel, M; Haddad, H

    2015-05-01

    Electrical storm refers to a state of cardiac electrical instability characterized by multiple episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF) within a relatively short period of time and is associated with increased mortality and morbidity. The management of electrical storm involves a variety of strategies, including sedation, anti-arrhythmic and electrolyte replacement as well as revascularization and electrical ablation. However, the management strategy in patients with refractory storm is less clear and may require more invasive approaches. We present a case of severe ventricular tachycardia storm refractory to conservative management that was managed with a HeartMate II left ventricular assist device.

  3. Associations between circulating components of the renin-angiotensin-aldosterone system and left ventricular mass.

    PubMed Central

    Schunkert, H.; Hense, H. W.; Muscholl, M.; Luchner, A.; Kürzinger, S.; Danser, A. H.; Riegger, G. A.

    1997-01-01

    OBJECTIVE: Cardiac growth may be modulated in part by the trophic effects of neurohormones. The aim of the present study was to investigate the relation between the basal activity of the renin-angiotensin-aldosterone system and left ventricular mass. DESIGN: A population based sample of 615 middle-age subjects was studied by standardised echocardiography; anthropometric measurements; and biochemical quantification of renin, pro-renin, angiotensinogen, angiotensin converting enzyme (ACE), and aldosterone. RESULTS: Echocardiographic left ventricular mass index correlated significantly with arterial blood pressure, age, and body mass index. In addition, in men ACE activity was significantly related to left ventricular mass index in univariate (P = 0.0007) and multivariate analyses (P = 0.008). Men with left ventricular hypertrophy presented with significantly higher serum ACE concentrations than those with normal left ventricular mass index (P = 0.002). In both men and women serum aldosterone was strongly related to septal and posterior wall thickness. Furthermore, in women serum aldosterone was positively and independently associated with left ventricular mass index (P = 0.0001). This effect was most prominent in hypertensive women. Finally, women with left ventricular hypertrophy presented with significantly higher serum aldosterone (P = 0.01). No significant associations with left ventricular mass index were observed for angiotensinogen, renin, or pro-renin. CONCLUSIONS: The data suggest that the variability of serum ACE or aldosterone, as occurred in this large population based sample, may contribute to the modulation of left ventricular mass. Images PMID:9038690

  4. Usefulness of rate regulation through continuous ventricular pacing in patients with drug-controlled slower atrial fibrillation and normal or depressed left ventricular systolic function.

    PubMed

    Chiladakis, John; Koutsogiannis, Nikolaos; Kalogeropoulos, Andreas; Zagli, Fani; Arvanitis, Panagiotis; Alexopoulos, Dimitrios

    2008-11-01

    We studied 33 clinically stable patients with permanent atrial fibrillation (AF), implanted with a ventricular demand rate-responsive (VVIR) pacemaker or an automatic defibrillator, in order to evaluate whether continuous right ventricular apex pacing (VP) conferring rate regulation may be advantageous when compared with slower drug-controlled AF. Devices were chronically programmed at ventricular backup pacing. Patients were divided in two groups according to their normal (n = 17) or depressed (n = 16) left ventricular systolic function (LVSF). Ventricular function was studied by using tissue Doppler and color M-mode and echocardiography, as well as B-type natriuretic peptide (BNP) measurements. Baseline data during AF were compared to corresponding measurements following a 1-month pacing period after the devices were programmed at a base rate of 70 beats/min. In both groups, VP worsened some indexes of left and right ventricular function (P < 0.05) without significantly affecting cardiac output, left ventricular filling pressures and BNP (P = not significant). We conclude that VP should not be considered advantageous compared to slower AF.

  5. Metabolic polymorphisms and cancer susceptibility.

    PubMed

    Smith, G; Stanley, L A; Sim, E; Strange, R C; Wolf, C R

    1995-01-01

    The vast majority of cancers arise as a consequence of exposure to environmental agents that are toxic or mutagenic. In response to this, all higher organisms have evolved complex mechanisms by which they can protect themselves from environmental challenge. In many cases, this involves an adaptive response in which the levels of expression of enzymes active in the metabolism and detoxification of the foreign chemical are induced. The best characterized of these enzyme systems are the cytochrome P450s, the GSTs and the NATs. An unfortunate consequence of many of these reactions, however, is the creation of a toxic or mutagenic reaction product from chemicals that require metabolic activation before realizing their full carcinogenic potential. Altered expression of one or more of these drug metabolizing enzymes can therefore be predicted to have profound toxicological consequences. Genetic polymorphisms with well defined associated phenotypes have now been characterized in P450, GST and NAT genes. Indeed, many of these polymorphisms have been associated with decreased or increased metabolism of many tumour promoters and chemical carcinogens and hence offer protection against or increased susceptibility to many distinct tumour types.

  6. A new polymorph of physcion.

    PubMed

    Hopf, Henning; Jones, Peter G; Goclik, Eva; Aust, Pauline; Rödiger, Johanna

    2012-08-01

    The structure of the title compound, 7-methoxy-2-methyl-4,5-dihydroxyanthracene-9,10-dione, C(16)H(12)O(5), was originally reported by Ulický et al. [Acta Cryst. (1991). C47, 1879-1881] in the space group P2(1)2(1)2(1) [polymorph (Io)]. The new polymorph, (Im), crystallizes in the space group P2(1)/c. The molecular structures are closely similar, with both -OH groups forming intramolecular hydrogen bonds to one of the neighbouring quinone O atoms, thus slightly lengthening this C=O bond; the pattern of C-C bond lengths in the ring system is consistent with some contribution from a resonance form with a negative charge at the hydrogen-bonded quinone O atom and an aromatic region around its neighbouring C atoms. The packing of (Im) is simpler than the extensively crosslinked pattern of (Io), with molecular tapes connected by classical (but three-centre) and `weak' hydrogen bonds, parallel to [201].

  7. Clinical use of ultrashort-lived radionuclide krypton-81m for noninvasive analysis of right ventricular performance in normal subjects and patients with right ventricular dysfunction.

    PubMed

    Nienaber, C A; Spielmann, R P; Wasmus, G; Mathey, D G; Montz, R; Bleifeld, W H

    1985-03-01

    The ultrashort-lived radionuclide krypton-81m, eluted in 5% dextrose from a bedside rubidium-81m generator, was intravenously infused for rapid imaging of the right-sided heart chambers in the right anterior oblique projection adjusted for optimal right atrioventricular separation. Left-sided heart and lung background was minimized by rapid decay and efficient exhalation of krypton-81m, requiring no algorithm for background correction. A double region of interest method decreased the variability in the assessment of ejection fraction to 5%. In 10 normal subjects, 11 patients with pulmonary hypertension, 4 patients with right ventricular outflow tract obstruction and 4 patients with right ventricular infarction, right ventricular ejection fraction determined by krypton-81m equilibrium blood pool imaging ranged from 14 to 76%. The correlation between these values and those determined by cineangiography according to Simpson's rule was close: r = 0.93 for all data points (p less than 0.001), r = 0.92 for studies at rest (p less than 0.001) and r = 0.93 for exercise studies (p less than 0.001). Exercise-related changes in right ventricular function revealed a disturbed functional reserve with pulmonary hypertension and right ventricular infarction, whereas in compensated right ventricular outflow tract obstruction there was a physiologic increase in ejection fraction with exercise (p less than 0.001). Thus, equilibrium-gated right ventricular imaging using ultrashort-lived krypton-81m is a simple, accurate and reproducible method with potential for serial assessment of right ventricular ejection fraction in a variety of right ventricular anatomic and functional abnormalities, both at rest and during exercise. Advantages of this method include an extremely low radiation dose to patients and clear right atrioventricular separation without the need to correct for background activity.

  8. Non-β-blocking R-carvedilol enantiomer suppresses Ca2+ waves and stress-induced ventricular tachyarrhythmia without lowering heart rate or blood pressure

    PubMed Central

    Zhang, Jingqun; Zhou, Qiang; Smith, Chris D.; Chen, Haiyan; Tan, Zhen; Chen, Biyi; Nani, Alma; Wu, Guogen; Song, Long-Sheng; Fill, Michael; Back, Thomas G.; Wayne Chen, S.R.

    2016-01-01

    Carvedilol is the current β-blocker of choice for suppressing ventricular tachyarrhythmia (VT). However, carvedilol’s benefits are dose-limited, attributable to its potent β-blocking activity that can lead to bradycardia and hypotension. The clinically used carvedilol is a racemic mixture of β-blocking S-carvedilol and non-β-blocking R-carvedilol. We recently reported that novel non-β-blocking carvedilol analogues are effective in suppressing arrhythmogenic Ca2+ waves and stress-induced VT without causing bradycardia. Thus, the non-β-blocking R-carvedilol enantiomer may also possess this favourable anti-arrhythmic property. To test this possibility, we synthesized R-carvedilol and assessed its effect on Ca2+ release and VT. Like racemic carvedilol, R-carvedilol directly reduces the open duration of the cardiac ryanodine receptor (RyR2), suppresses spontaneous Ca2+ oscillations in human embryonic kidney (HEK) 293 cells, Ca2+ waves in cardiomyocytes in intact hearts and stress-induced VT in mice harbouring a catecholaminergic polymorphic ventricular tachycardia (CPVT)-causing RyR2 mutation. Importantly, R-carvedilol did not significantly alter heart rate or blood pressure. Therefore, the non-β-blocking R-carvedilol enantiomer represents a very promising prophylactic treatment for Ca2+-triggered arrhythmia without the bradycardia and hypotension often associated with racemic carvedilol. Systematic clinical assessments of R-carvedilol as a new anti-arrhythmic agent may be warranted. PMID:26348911

  9. Effect of CYP2C9 and VKORC1 Gene Variants on Warfarin Response in Patients with Continuous-Flow Left Ventricular Assist Devices.

    PubMed

    Topkara, Veli K; Knotts, Robert J; Jennings, Douglas L; Garan, A Reshad; Levin, Allison P; Breskin, Alexander; Castagna, Francesco; Cagliostro, Barbara; Yuzefpolskaya, Melana; Takeda, Koji; Takayama, Hiroo; Uriel, Nir; Mancini, Donna M; Eisenberger, Andrew; Naka, Yoshifumi; Colombo, Paolo C; Jorde, Ulrich P

    2016-01-01

    Bleeding and thrombotic complications continue to plague continuous-flow left ventricular assist device (CF-LVAD) therapy in patients with end-stage heart failure. Warfarin genotyping information can be incorporated into decision making for initial dosing as recommended by the Food and Drug Administration; however, clinical utility of this data in the CF-LVAD population has not been well studied. Genotypes testing for CYP2C9 and VCORC1 polymorphisms were determined in 90 CF-LVAD patients. Outcomes studied were the association of CYP2C9 (*1, *2, or *3) and VKORC1 (-1639 G>A) gene variants with time-to-target international normalized ratio (INR), total warfarin dose, maintenance warfarin dose. Continuous-flow left ventricular assist device patients carrying a rare variant in the VKORC1 gene had a significantly lower cumulative warfarin dose until target INR achieved (18.9 vs. 35.0 mg, p = 0.002), days spent until INR target achieved (4.9 vs. 7.0 days, p = 0.021), and discharge warfarin dose (3.2 vs. 5.6 mg, p = 0.001) compared with patients with wild-type genotype. Genotype-guided warfarin dosing may lead to safer anticoagulation and potentially improve outcomes in CF-LVAD patients. PMID:27258224

  10. Effect of CYP2C9 and VKORC1 Gene Variants on Warfarin Response in Patients with Continuous-Flow Left Ventricular Assist Devices.

    PubMed

    Topkara, Veli K; Knotts, Robert J; Jennings, Douglas L; Garan, A Reshad; Levin, Allison P; Breskin, Alexander; Castagna, Francesco; Cagliostro, Barbara; Yuzefpolskaya, Melana; Takeda, Koji; Takayama, Hiroo; Uriel, Nir; Mancini, Donna M; Eisenberger, Andrew; Naka, Yoshifumi; Colombo, Paolo C; Jorde, Ulrich P

    2016-01-01

    Bleeding and thrombotic complications continue to plague continuous-flow left ventricular assist device (CF-LVAD) therapy in patients with end-stage heart failure. Warfarin genotyping information can be incorporated into decision making for initial dosing as recommended by the Food and Drug Administration; however, clinical utility of this data in the CF-LVAD population has not been well studied. Genotypes testing for CYP2C9 and VCORC1 polymorphisms were determined in 90 CF-LVAD patients. Outcomes studied were the association of CYP2C9 (*1, *2, or *3) and VKORC1 (-1639 G>A) gene variants with time-to-target international normalized ratio (INR), total warfarin dose, maintenance warfarin dose. Continuous-flow left ventricular assist device patients carrying a rare variant in the VKORC1 gene had a significantly lower cumulative warfarin dose until target INR achieved (18.9 vs. 35.0 mg, p = 0.002), days spent until INR target achieved (4.9 vs. 7.0 days, p = 0.021), and discharge warfarin dose (3.2 vs. 5.6 mg, p = 0.001) compared with patients with wild-type genotype. Genotype-guided warfarin dosing may lead to safer anticoagulation and potentially improve outcomes in CF-LVAD patients.

  11. Non-β-blocking R-carvedilol enantiomer suppresses Ca2+ waves and stress-induced ventricular tachyarrhythmia without lowering heart rate or blood pressure.

    PubMed

    Zhang, Jingqun; Zhou, Qiang; Smith, Chris D; Chen, Haiyan; Tan, Zhen; Chen, Biyi; Nani, Alma; Wu, Guogen; Song, Long-Sheng; Fill, Michael; Back, Thomas G; Chen, S R Wayne

    2015-09-01

    Carvedilol is the current β-blocker of choice for suppressing ventricular tachyarrhythmia (VT). However, carvedilol's benefits are dose-limited, attributable to its potent β-blocking activity that can lead to bradycardia and hypotension. The clinically used carvedilol is a racemic mixture of β-blocking S-carvedilol and non-β-blocking R-carvedilol. We recently reported that novel non-β-blocking carvedilol analogues are effective in suppressing arrhythmogenic Ca(2+) waves and stress-induced VT without causing bradycardia. Thus, the non-β-blocking R-carvedilol enantiomer may also possess this favourable anti-arrhythmic property. To test this possibility, we synthesized R-carvedilol and assessed its effect on Ca(2+) release and VT. Like racemic carvedilol, R-carvedilol directly reduces the open duration of the cardiac ryanodine receptor (RyR2), suppresses spontaneous Ca(2+) oscillations in human embryonic kidney (HEK) 293 cells, Ca(2+) waves in cardiomyocytes in intact hearts and stress-induced VT in mice harbouring a catecholaminergic polymorphic ventricular tachycardia (CPVT)-causing RyR2 mutation. Importantly, R-carvedilol did not significantly alter heart rate or blood pressure. Therefore, the non-β-blocking R-carvedilol enantiomer represents a very promising prophylactic treatment for Ca(2+)- triggered arrhythmia without the bradycardia and hypotension often associated with racemic carvedilol. Systematic clinical assessments of R-carvedilol as a new anti-arrhythmic agent may be warranted.

  12. Spinning up the polymorphs of calcium carbonate

    PubMed Central

    Boulos, Ramiz A.; Zhang, Fei; Tjandra, Edwin S.; Martin, Adam D.; Spagnoli, Dino; Raston, Colin L.

    2014-01-01

    Controlling the growth of the polymorphs of calcium carbonate is important in understanding the changing environmental conditions in the oceans. Aragonite is the main polymorph in the inner shells of marine organisms, and can be readily converted to calcite, which is the most stable polymorph of calcium carbonate. Both of these polymorphs are significantly more stable than vaterite, which is the other naturally occurring polymorph of calcium carbonate, and this is reflected in its limited distribution in nature. We have investigated the effect of high shear forces on the phase behaviour of calcium carbonate using a vortex fluidic device (VFD), with experimental parameters varied to explore calcium carbonate mineralisation. Variation of tilt angle, rotation speed and temperature allow for control over the size, shape and phase of the resulting calcium carbonate. PMID:24448077

  13. Management of ventricular fibrillation or unstable ventricular tachycardia in patients with congenital long-QT syndrome: a suggested modification to ACLS guidelines.

    PubMed

    Homme, Jason H; White, Roger D; Ackerman, Michael J

    2003-10-01

    Prolongation of the QT interval is a known risk factor for syncope, seizures and sudden cardiac death. Most patients with QT prolongation have an acquired cause, but congenital forms of QT prolongation are being increasingly recognized. However, existing advanced cardiac life support (ACLS) treatment algorithms for prolonged QT mediated ventricular fibrillation pertains to acquired long-QT syndrome (LQTS). Here, a young patient with out-of-hospital cardiac arrest secondary to congenital LQTS illustrates critical exceptions to the current ACLS treatment algorithms for ventricular fibrillation and unstable ventricular tachycardia when QT prolongation is congenital in origin. A clarified ACLS algorithm is proposed.

  14. Frequent Premature Ventricular Complexes Originating from the Left Ventricular Summit Successfully Ablated from the Proximal Great Cardiac Vein Using an Impedance-based Electroanatomical Mapping System.

    PubMed

    Nagata, Yoshihisa; Ogawa, Masahiro; Goto, Shunichiro; Morii, Joji; Imaizumi, Satoshi; Yasuda, Tomoo; Matsumoto, Naomichi; Saku, Keijiro

    2016-01-01

    We herein report a 58-year-old woman with frequent premature ventricular complexes (PVCs) originating from the left ventricular summit. The earliest ventricular activation of spontaneous PVCs was recorded in the proximal site of the great cardiac vein, which was simultaneously mapped and conducted using an impedance-based electroanatomical mapping system. Irrigated radiofrequency with a starting power output of 20 W and maximal temperature set at 40°C was applied with 10 Ω impedance fall, resulting in total disappearance of the frequent PVCs. The patient has remained free from PVCs for 18 months without requiring antiarrhythmic drug therapy. PMID:27374677

  15. Assessment of right ventricular systolic function by tissue Doppler echocardiography.

    PubMed

    Kjærgaard, Jesper

    2012-03-01

    This thesis summarizes a series of studies performed in order to assess the clinical usefulness of a novel echocardiographic technology that allows non-invasive assessment of regional right ventricular myocardial velocities and deformation: tissue Doppler echocardiography. While the technology is a promising tool for improving our understanding of right ventricular hemodynamics, several aspects of the technology must be evaluated. The accuracy and reproducibility of the technology is evaluated in vitro, and normal values, impact of changes in loading of the right ventricle, response to exercise and pharmacological pulmonary vasodilatation is established in normal subjects. The diagnostic and prognostic importance of adding tissue Doppler echocardiography to conventional echocardiographic and clinical parameters was evaluated in studies on patients with diseases associated with different modes of impact on right ventricular hemodynamics: pulmonary embolism, Arrhythmogenic right ventricular cardiomyopathy and pulmonary regurgitation, the latter in an animal model. The conclusions of the thesis are: Color tissue Doppler echocardiography accurately measures velocities, SR and strain in vitro. No systematic bias between ultrasound systems can be found, and accuracy of the measurements is good. However, the reproducibility of measurements in a test-retest design can limit the usefulness of the technology in daily clinical use, as 25% to 80% of change would be needed for the technology to identify a change in individual patients [I]. Normal values of tissue Doppler based measurements of RV regional velocities, SR and strain exist, and apply to both sexes and in all age groups with the exception of slightly decreasing values in strain with increasing age. Increasing preload and afterload changes regional myocardial velocities, but no changes in SR, strain or isovolumic acceleration could be observed [II and III]. Tissue Doppler echocardiography of the RV free wall in non

  16. Intracranial ventricular catheter placement with a smartphone assisted instrument.

    PubMed

    Thomale, Ulrich-W

    2015-01-01

    Mobile technology has recently been introduced for blood pressure measurements or glucose level controls. In surgical disciplines the use of smartphone applications is mostly restricted as training tools or knowledge resources. Simple surgical procedures which are performed often in certain disciplines may be performed with limited accuracy since routine and overwork of medical staff lead to less awareness to possible mistakes. In these cases simple and effective means are necessary to achieve better patient safety.In this context, a surgical instrument for ventricular catheter placement in neurosurgical patients was designed which is assisted by measurements undertaken in a smartphone software application specifically visualizing the use of this instrument and achieving better accuracy for catheter positioning. On theoretical ground, the angulation of the catheter trajectory towards the surface of the skull in a coronal reconstructed CT or MR image is determined as the simplified but the most relevant individual parameter for correct ventricular catheter placement. Transfer of a CT/MRI image onto the smartphone can be performed via mail as anonymous file. Using this image, the trajectory measurement can be performed individually in a few steps by calibration of the image size, definition of the frontal entry point, and virtual placement of the instrument on the surface of the skull. Then the angulation can be adjusted and measured to place the catheter's trajectory towards the ipsilateral ventricle and the catheter length is determined. The parameters are now given by the app and visualized on the image in order to be applied to the surgical site of the patient.The tool represents a widely available and cost-effective solution as navigation technique which is simple to apply in order to achieve better accuracy in ventricular catheter placement for higher safety in a large cohort of neurosurgical patients. PMID:25626554

  17. Passive ventricular mechanics modelling using MRI of structure and function.

    PubMed

    Wang, V Y; Lam, H I; Ennis, D B; Young, A A; Nash, M P

    2008-01-01

    Patients suffering from dilated cardiomyopathy or myocardial infarction can develop left ventricular (LV) diastolic impairment. The LV remodels its structure and function to adapt to pathophysiological changes in geometry and loading conditions and this remodeling process can alter the passive ventricular mechanics. In order to better understand passive ventricular mechanics, a LV finite element model was developed to incorporate physiological and mechanical information derived from in vivo magnetic resonance imaging (MRI) tissue tagging, in vivo LV cavity pressure recording and ex vivo diffusion tensor MRI (DTMRI) of a canine heart. MRI tissue tagging enables quantitative evaluation of cardiac mechanical function with high spatial and temporal resolution, whilst the direction of maximum water diffusion (the primary eigenvector) in each voxel of a DTMRI directly correlates with the myocardial fibre orientation. This model was customized to the geometry of the canine LV during diastasis by fitting the segmented epicardial and endocardial surface data from tagged MRI using nonlinear finite element fitting techniques. Myofibre orientations, extracted from DTMRI of the same heart, were incorporated into this geometric model using a free form deformation methodology. Pressure recordings, temporally synchronized to the tissue tagging MRI data, were used to simulate the LV deformation during diastole. Simulation of the diastolic LV mechanics allowed us to estimate the stiffness of the passive LV myocardium based on kinematic data obtained from tagged MRI. This integrated physiological model will allow more insight into the regional passive diastolic mechanics of the LV on an individualized basis, thereby improving our understanding of the underlying structural basis of mechanical dysfunction in pathological conditions.

  18. Compound and Digenic Heterozygosity Contributes to Arrhythmogenic Right Ventricular Cardiomyopathy

    PubMed Central

    Xu, Tianhong; Yang, Zhao; Vatta, Matteo; Rampazzo, Alessandra; Beffagna, Giorgia; Pillichou, Kalliopi; Scherer, Steven E.; Saffitz, Jeffrey; Kravitz, Joshua; Zareba, Wojciech; Danieli, Gian Antonio; Lorenzon, Alessandra; Nava, Andrea; Bauce, Barbara; Thiene, Gaetano; Basso, Cristina; Calkins, Hugh; Gear, Kathy; Marcus, Frank; Towbin, Jeffrey A.

    2010-01-01

    Objective: To define the genetic basis of arrhythmogenic right ventricular cardiomyopathy. Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC), characterized by right ventricular fibrofatty replacement and arrhythmias, causes sudden death. Autosomal dominant Inheritance, reduced penetrance, and 7 desmosome-encoding causative genes are known. The basis of low penetrance is poorly understood. Methods: ARVC probands and family members were enrolled, blood obtained, lymphoblastoid cell lines immortalized, DNA extracted, PCR amplification of desmosome-encoding genes performed, PCR products sequenced and diseased tissue samples studied for intercellular junction protein distribution using confocal immunofluorescence microscopy and antibodies against key proteins. Results: We identified 21 variants in plakophilin-2 (PKP2) in 38 of 198 probands (19%), including missense, nonsense, splice site, and deletion/insertion mutations. Pedigrees showed wide intra-familial variability (severe early-onset disease to asymptomatic individuals). In 9/38 probands, PKP2 variants were identified that were encoded in trans (compound heterozygosity). The 38 probands hosting PKP2 variants were screened for other desmosomal genes mutations; second variants (digenic heterozygosity) were identified in 16/38 subjects with PKP2 variants (42%) including desmoplakin (DSP, n=6), desmoglein-2 (DSG2, n=5), plakophilin-4 (PKP4, n=1), and desmocollin-2 (DSC2, n=1). Heterozygous mutations in non-PKP 2desmosomal genes occurred in 14/198 subjects (7%), including DSP (n=4), DSG2 (n=5), DSC2 (n=3), and junctional plakoglobin (JUP, n=2). All variants occurred in conserved regions; none were identified in 700 ethnic-matched controls. Immunohistochemical analysis demonstrated abnormalities of protein architecture. Conclusions: These data suggest that the genetic basis of ARVC includes reduced penetrance with compound and digenic heterozygosity. Disturbed junctional cytoarchitecture in subjects

  19. 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. PMID:16220198

  20. Role of tissue structure on ventricular wall mechanics.

    PubMed

    Coppola, Benjamin A; Omens, Jeffrey H

    2008-09-01

    It is well known that systolic wall thickening in the inner half of the left ventricular (LV) wall is of greater magnitude than predicted by myofiber contraction alone. Previous studies have related the deformation of the LV wall to the orientation of the laminar architecture. Using this method, wall thickening can be interpreted as the sum of contributions due to extension, thickening, and shearing of the laminar sheets. We hypothesized that the thickening mechanics of the ventricular wall are determined by the structural organization of the underlying tissue, and may not be influenced by factors such as loading and activation sequence. To test this hypothesis, we calculated finite strains from biplane cineradiography of transmural markers implanted in apical (n = 22) and basal (n = 12) regions of the canine anterior LV free wall. Strains were referred to three-dimensional laminar microstructural axes measured by histology. The results indicate that sheet angle is of opposite sign in the apical and basal regions, but absolute value differs only in the subepicardium. During systole, shearing and extension of the laminae contribute the most to wall thickening, accounting for >90% (transmural average) at both apex and base. These two types of deformation are also most prominent during diastolic inflation. Increasing afterload has no effect on the pattern of systolic wall thickening, nor does reversing transmural activation sequence. The pattern of wall thickening appears to be a function of the orientation of the laminar sheets, which vary regionally and transmurally. Thus, acute interventions do not appear to alter the contributions of the laminae to wall thickening, providing further evidence that the structural architecture of the ventricular wall is the dominant factor for its regional mechanical function.