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Sample records for phase ventricular tachycardia

  1. Ventricular tachycardia

    MedlinePlus

    ... of implanting a device called an implantable cardioverter defibrillator (ICD). The ICD is most often implanted in ... tachycardia; V tach; Tachycardia - ventricular Images Implantable cardioverter-defibrillator References Olgin JE, Zipes DP. Specific Arrhythmias: Diagnosis ...

  2. [Treatment of ventricular tachycardia].

    PubMed

    Iturralde Torres, P

    2001-01-01

    Evaluation and management of postinfarct ventricular tachycardia has changed dramatically in the past two decades. The introduction of the implantable cardioverter defibrillator has played a major role in this change, alternating both, the purpose of the patients evaluation and treatment options. Episodes of sustained ventricular tachycardia can occur in a variety of clinical settings; the most common of which is the patient who has suffered a myocardial infarction. In this paper, I explore the causes and effects of some of these changes and review current strategies, specially the radiofrequency catheter ablation, for the management of the patient with postinfarct ventricular tachycardia. PMID:11565352

  3. Ventricular Tachycardias: Characteristics and Management.

    PubMed

    Baldzizhar, Aksana; Manuylova, Ekaterina; Marchenko, Roman; Kryvalap, Yury; Carey, Mary G

    2016-09-01

    Ventricular tachycardias include ventricular tachycardia, ventricular fibrillation, and torsades de pointes; although these rhythms may be benign and asymptomatic, others may be life threatening and lead to increased morbidity and mortality. To optimize patient outcomes, ventricular tachycardias need to be rapidly diagnosed and managed, and often the electrocardiogram (ECG) is the first and only manifestation of a cardiac defect. Understanding of the initial electrocardiographic pattern and subsequent changes can lead to early intervention and an improved outcome. This article describes mechanisms, ECG characteristics, and management of ventricular tachycardias. PMID:27484660

  4. Epicardial ventricular tachycardia.

    PubMed

    Garan, Hasan

    2013-12-01

    In ventricular tachycardia (VT) arising in the myocardial tissue, the site of origin may be the endocardium, mid-myocardium or epicardium. The incidence of epicardial origin varies with the underlying heart disease, and is probably not more than 20% in ischemic heart disease and higher in non-ischemic cardiomyopathies. Percutaneous subxiphoid access to the pericardial space has enabled a non-surgical approach to catheter mapping and ablation of epicardial VT. Several algorithms are available for electrocardiographic recognition of epicardial origin. Idiopathic epicardial VTs are rare but may be curable by catheter ablation. The electrophysiologic principles guiding the mapping and ablation of epicardial VTs are similar to those used for endocardial VTs, but the biophysics of energy delivery may be different. Complications of the epicardial approach are also different from those of endocardial ablation, and specific precautions have to be taken to protect the coronary arteries and phrenic nerves and to avoid pericardial tamponade. PMID:24351953

  5. Prolonged QT interval at onset of acute myocardial infarction in predicting early phase ventricular tachycardia

    SciTech Connect

    Taylor, G.J.; Crampton, R.S.; Gibson, R.S.; Stebbins, P.T.; Waldman, M.T.; Beller, G.A.

    1981-07-01

    The prospectively assessed time course of changes in ventricular repolarization during acute myocardial infarction (AMI) is reported in 32 patients admitted 2.0 +/- 1.8 (SD) hours after AMI onset. The initial corrected QT interval (QTc) upon hospitalization was longer in the 14 patients developing ventricular tachycardia (VT) within the first 48 hours as compared to QTc in the eight patients with frequent ventricular premature beats (VPBs) and to QTc in the 10 patients with infrequent VPBs. By the fifth day after AMI onset, the QTc shortened significantly only in the VT group, suggesting a greater initial abnormality of repolarization in these patients. All 32 patients had coronary angiography, radionuclide ventriculography, and myocardial perfusion scintigraphy before hospital discharge. Significant discriminating factors related to early phase VT in AMI included initially longer QT and QTc intervals, faster heart rate, higher peak serum levels of creatine kinase, acute anterior infarction, angiographically documented proximal stenosis of the left anterior descending coronary artery, and scintigraphic evidence of hypoperfusion of the interventricular septum. Prior infarction, angina pectoris, hypertension, multivessel coronary artery disease, and depressed left ventricular ejection fraction did not provide discrimination among the three different ventricular arrhythmia AMI groups. Researchers conclude that (1) the QT interval is frequently prolonged early in AMI, (2) the initial transiently prolonged ventricular repolarization facilitates and predicts complex ventricular tachyarrhythmias within the first 48 hours of AMI, (3) jeopardized blood supply to the interventricular septum frequently coexists, and (4) therapeutic enhancement of rapid recovery of the ventricular repolarization process merits investigation for prevention of VT in AMI.

  6. [Drug-induced ventricular tachycardia].

    PubMed

    Fauchier, J P; Fauchier, L; Babuty, D; Breuillac, J C; Cosnay, P; Rouesnel, P

    1993-05-01

    Certain drugs can induce ventricular tachycardia (VT) by creating reentry, ventricular after potentials or exaggerating the slope of phase 4. These may or may not be symptomatic, sustained or non-sustained and have variable ECG appearances: monomorphic or polymorphic, bidirectional, torsades de pointes. They risk degenerating into ventricular flutter of fibrillation and have been held responsible for the increased mortality observed unexpectedly in some long-term treatments. The drugs responsible are mainly those used in cardiology, probably due to predisposing circumstances (cardiomegaly, cardiac failure, previous severe ventricular arrhythmias, therapeutic associations, metabolic abnormalities). These include primarily the antiarrhythmic drugs (IA, IC, sotalol and bepridil), digitalis, sympathomimetics and phosphodiesterase inhibitors. These complications may be toxic or idiosyncratic, in patients with or without cardiac disease, and may also occur with other drugs: vasodilators and anti-anginal drugs (lidoflazine, vincamine, fenoxedil), psychotropic agents (phenothiazine and imipramine), antimitotics, antimalarials (chloroquine) or antibiotics (erythromycin, pentamidine). The prognosis is severe and the treatment is often difficult which makes prevention, helped by repeated surface ECG (or Holter monitoring), very important with careful assessment of patients at risk. PMID:8267504

  7. 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 ...

  8. 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

  9. Epicardial Ablation For Ventricular Tachycardia

    PubMed Central

    Maccabelli, Giuseppe; Mizuno, Hiroya; Della Bella, Paolo

    2012-01-01

    Epicardial ablation has lately become a necessary tool to approach some ventricular tachycardias in different types of cardiomyopathy. Its diffusion is now limited to a few high volume centers not because of the difficulty of the pericardial puncture but since it requires high competence not only in the VT ablation field but also in knowing and recognizing the possible complications each of which require a careful treatment. This article will review the state of the art of epicardial ablation with special attention to the procedural aspects and to the possible selection criteria of the patients PMID:23233758

  10. Echocardiographic Predictors of Ventricular Tachycardia

    PubMed Central

    Catanzaro, John N; Makaryus, John N; Makaryus, Amgad N; Sison, Cristina; Vavasis, Christos; Fan, Dali; Jadonath, Ram

    2014-01-01

    BACKGROUND Patients with structural heart disease are prone to ventricular tachycardia (VT) and ventricular fibrillation (VF), which account for the majority of sudden cardiac deaths (SCDs). We sought to examine echocardiographic parameters that can predict VT as documented by implantable cardioverter-defibrillator (ICD) appropriate discharge. We examine echocardiographic parameters other than ejection fraction that may predict VT as recorded via rates of ICD discharge. METHODS Analysis of 586 patients (469 males; mean age = 68 ± 3 years; mean follow-up time of 11 ± 14 months) was undertaken. Echo parameters assessed included left ventricular (LV) internal end diastolic/systolic dimension (LVIDd, LVIDs), relative wall thickness (RWT), and left atrial (LA) size. RESULTS The incidence of VT was 0.22 (114 VT episodes per 528 person-years of follow-up time). Median time-to-first VT was 3.8 years. VT was documented in 79 patients (59 first VT incidence, 20 multiple). The echocardiographic parameter associated with first VT was LVIDs >4 cm (P = 0.02). CONCLUSION The main echocardiographic predictor associated with the first occurrence of VT was LVIDs >4 cm. Patients with an LVIDs >4 cm were 2.5 times more likely to have an episode of VT. Changes in these echocardiographic parameters may warrant aggressive pharmacologic therapy and implantation of an ICD. PMID:25861227

  11. 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.

  12. Partial Unroofed Coronary Sinus Associated With Upper Septal Ventricular Tachycardia and Atrioventricular Nodal Reentrant Tachycardia

    PubMed Central

    Bohora, Shomu; Singh, Parvindar; Shah, Kaushal

    2016-01-01

    A 58 year old gentleman with complaints of palpitations and documented tachycardia was found to have a dilated right atrium, right ventricle and coronary sinus, which were due to partial unroofed coronary sinus without a left superior vena cava. He had upper septal ventricular tachycardia and atrio-ventricular nodal reentrant tachycardia, which was successfully treated by radiofrequency ablation. PMID:25852246

  13. Carcinoid Syndrome-Induced Ventricular Tachycardia

    PubMed Central

    Ahmadjee, Abdulmohsin; Morshedzadeh, Jack H.; Ranjan, Ravi

    2016-01-01

    Introduction. Carcinoid tumors are rare neuroendocrine malignancies that secrete multiple bioactive substances. These bioactive substances are responsible for the carcinoid syndrome characterized by diarrhea, flushing, syncope, and right-sided valvular heart disease. Previous case reports have described carcinoid syndrome associated with coronary vasospasm and the well-characterized carcinoid heart disease. Case. Our patient is a 73-year-old female with complex past medical history most notable for metastatic carcinoid tumors diagnosed in 2013-05. She initially presented in 2014-09 with syncope and dizziness associated with sinus pause on an event monitor. She received a pacemaker given normal left ventricular function and was discharged. However, she was readmitted with similar symptoms corresponding to multiple episodes of ventricular tachycardia. She was started on high-dose beta blockade and has had no recurrence of arrhythmia over a follow-up period of 12 months. Conclusion. We hypothesize that the patient's ventricular tachycardia was mediated by the multiple bioactive substances secreted by her carcinoid tumors. Her carcinoid tumor biomarkers were elevated and other explanations for arrhythmia were investigated and ruled out. To our knowledge, this is the first case of ventricular tachycardia mediated by carcinoid syndrome and suppressed by beta-blocker. Further investigation into this relationship is needed. PMID:27088017

  14. [Fascicular ventricular tachycardia in a 49-year-old patient].

    PubMed

    Bellmann, Barbara; Nagel, Patrick; Tscholl, Verena; Roser, Mattias; Rillig, Andreas

    2016-06-01

    We report a 49-year-old patient who presented with tachycardia in our emergency room. The 12-lead ECG showed a wide complex tachycardia with a heart rate of 234 beats per minute. After structural heart disease was excluded via echocardiography, coronary angiography and magnetic resonance imaging, an electrophysiological study was performed. During programmed ventricular stimulation, a fascicular tachycardia was induced, which was successfully treated by radiofrequency ablation. Fascicular ventricular tachycardia is a rare tachycardia that occurs in patients without structural heart disease. Radiofrequency ablation can be performed safely and shows a high success rate. Differential diagnoses of fascicular ventricular tachycardias are substrate-based ventricular tachycardia and supraventricular tachycardia. PMID:27193769

  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. Catheter Ablation of Polymorphic Ventricular Tachycardia and Ventricular Fibrillation

    PubMed Central

    Peichl, Petr

    2013-01-01

    Recently, catheter ablation (CA) has become a therapeutic option to target focal triggers of polymorphic ventricular tachycardia and ventricular fibrillation (VF) in the setting of electrical storm (ES). This strategy was first described in subjects without organic heart disease (i.e. idiopathic VF) and subsequently in other conditions, especially in patients with ischaemic heart disease. In the majority of cases, the triggering focus originates in the ventricular Purkinje system. In patients with Brugada syndrome, besides ablation of focal trigger in the right ventricular outflow tract, modification of a substrate in this region has been described to prevent recurrences of VF. In conclusion, CA appears to be a reasonable strategy for intractable cases of ES due to focally triggered polymorphic ventricular tachycardia and VF. Therefore, early transport of the patient into the experience centre for CA should be considered since the procedure could be in some cases life-saving. Therefore, the awareness of this entity and link to the nearest expert centre are important.

  17. Triggered activity as a mechanism of recurrent ventricular tachycardia.

    PubMed Central

    Bhandari, A K; Hong, R A; Rahimtoola, S H

    1988-01-01

    Triggered activity was shown to be the likely mechanism of recurrent tachycardia in a 28 year old Vietnamese man. During baseline electrophysiological testing the tachycardia was induced consistently by prolonged atrial or ventricular pacing but not by premature extrastimuli. Moreover, the tachycardia coupling intervals varied directly with the cycle length of the initiating drive. Procainamide and propranolol did not suppress tachycardia, but verapamil terminated it and prevented its reinitiation. The origin of the tachycardia was localised to the left ventricular inferoapical segment and four direct current countershocks of 200 J each delivered via an electrode catheter abolished the tachycardia. During 12 months of follow up the patient was not treated with antiarrhythmic agents and the tachycardia did not recur. PMID:3370186

  18. New strategies for ventricular tachycardia and ventricular fibrillation ablation.

    PubMed

    Hooks, Darren A; Berte, Benjamin; Yamashita, Seigo; Mahida, Saagar; Sellal, Jean-Marc; Aljefairi, Nora; Frontera, Antonio; Derval, Nicolas; Denis, Arnaud; Hocini, Mélèze; Haïssaguerre, Michel; Jaïs, Pierre; Sacher, Frederic

    2015-03-01

    Patients with ventricular tachycardia (VT) and ventricular fibrillation (VF) and no reversible cause are difficult to treat. While implantable defibrillators prolong survival, many patients remain symptomatic due to device shocks and syncope. To address this, there have been recent advances in the catheter ablation of VT and VF. For example, non-invasive imaging has improved arrhythmia substrate characterisation, 3D catheter navigation tools have facilitated mapping of arrhythmia and substrate and ablation catheters have advanced in their ability to deliver effective lesions. However, the long-term success rates of ablation for VT and VF remain modest, with nearly half of treated patients developing recurrence within 2-3 years, and this drives the ongoing innovation in the field. This review focuses on the challenges particular to ablation of life-threatening ventricular arrhythmia, and the strategies that have been recently developed to improve procedural efficacy. Patient sub-groups that illustrate the use of new strategies are described. PMID:25666031

  19. Intravenous disopyramide phosphate and ventricular overdrive pacing in the termination of paroxysmal ventricular tachycardia.

    PubMed

    Camm, J; Ward, D; Washington, H G; Spurrell, R A

    1979-07-01

    Both antiarrhythmic drugs and bursts of rapid ventricular pacing provide alternatives to DC cardioversion for the treatment of paroxysmal ventricular tachycardia. This report considers the individual and combined success of burst ventricular pacing and intravenous disopyramide phosphate in the tretment of 11 examples of paroxysmal ventricular tachycardia. Rapid ventricular pacing, at a rate of up to 50 beats/min faster than the tachycardia rate terminated 7 of the tachycardias. Intravenous disopyramide resulted in increased tachycardiac cycle length (342 +/- 34 ms-385 +/- 56 ms), increased QRS complex width (147 +/- 42 ms-180 +/- 41 ms) and termination of 8 the tachycardias. The remaining 3 tachycardias could be terminated by bursts of ventricular pacing following the infusion of disopyramide. Of these, 2 could not be terminated prior to disopyramide. The use of both techniques allowed the extinction of all 11 tachycardias and prevented the need to proceed to DC conversion. PMID:95308

  20. Clinical Challenges in Catecholaminergic Polymorphic Ventricular Tachycardia.

    PubMed

    Imberti, Jacopo F; Underwood, Katherine; Mazzanti, Andrea; Priori, Silvia G

    2016-08-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inheritable cardiac disorder associated with exercise- and stress-induced sudden death in young individuals. Although important steps forward have been made in the comprehension and treatment of this disease, several aspects remain unclear. Firstly, from an epidemiological standpoint the actual prevalence of CPVT is still unknown and possibly underestimated. In addition, the diagnostic process remains very challenging and can be supported by genetic analysis in only about half of the cases. Finally, up to one third of CPVT patients continue to present complex arrhythmias despite beta blocker treatment; the role of newer therapeutic options, such as flecainide and left cardiac sympathetic denervation, needs to be further elucidated. All these points constitute challenges for the cardiologist in the management of CPVT patients and fuel research into new diagnostic, prognostic and therapeutic approaches. PMID:26948768

  1. Epicardial Ventricular Tachycardia Ablation for Which Patients?

    PubMed Central

    Roten, Laurent; Sacher, Frédéric; Daly, Matthew; Pascale, Patrizio; Komatsu, Yuki; Ramoul, Khaled; Scherr, Daniel; Chaumeil, Arnaud; Shah, Ashok; Denis, Arnaud; Derval, Nicolas; Hocini, Mélèze; Haïssaguerre, Michel; Jaïs, Pierre

    2012-01-01

    With the widespread use of implantable cardioverter-defibrillators, an increasing number of patients present with ventricular tachycardia (VT). Large multicentre studies have shown that ablation of VT successfully reduces recurrent VT and this procedure is being performed by an increasing number of centres. However, for a number of reasons, many patients experience VT recurrence after ablation. One important reason for VT recurrence is the presence of an epicardial substrate involved in the VT circuit which is not affected by endocardial ablation. Epicardial access and ablation is now frequently performed either after failed endocardial VT ablation or as first-line treatment in selected patients. This review will focus on the available evidence for identifying VT of epicardial origin, and discuss in which patients an epicardial approach would be benefitial. PMID:26835028

  2. [Case report: idiopathic ventricular tachycardia from the aortic sinus cusp].

    PubMed

    Tejera-Jurado, Luis Carlos; Nava, Santiago; Colín-Lizalde, Luis; Márquez, Manlio F; Gómez-Flores, Jorge; González-Hermosillo, Jesús Antonio; Iturralde-Torres, Pedro

    2009-01-01

    Idiopathic ventricular tachycardia is identified in 10% of the patients presenting with ventricular tachycardia, and they consist of various subtypes that can originate from different areas, including the aortic cusps which represent 0.7% of the total. Electrocardiographically, these ventricular tachycardias display a left bundle branch block pattern and inferior axis, and although rare, should be considered in the differential diagnosis with tachycardias originating from the septal region of the right ventricular outflow tract, which comprise 80% of the idiopathic ventricular tachycardias. Despite the vicinity of the left coronary artery ostium, radiofrequency catheter ablation can be curative in more than 90% of cases with a low risk (< 1% of serious complication). Therefore, it must be considered first-line therapy in patients who have failed or are intolerant to therapy with antiarrhythmic agents. The aim of this article is to describe the first case reported in Mexico of a successful ablation idiopathic ventricular tachycardia from the aortic sinus cusp in a patient with incessant ventricular tachycardia. PMID:19902669

  3. Catheter Ablation of Fascicular Ventricular Tachycardia

    PubMed Central

    Liu, Yaowu; Fang, Zhen; Yang, Bing; Kojodjojo, Pipin; Chen, Hongwu; Ju, Weizhu; Cao, Kejiang; Chen, Minglong

    2015-01-01

    Background— Fascicular ventricular tachycardia (FVT) is a common form of sustained idiopathic left ventricular tachycardia with an Asian preponderance. This study aimed to prospectively investigate long-term clinical outcomes of patients undergoing ablation of FVT and identify predictors of arrhythmia recurrence. Methods and Results— Consecutive patients undergoing FVT ablation at a single tertiary center were enrolled. Activation mapping was performed to identify the earliest presystolic Purkinje potential during FVT that was targeted by radiofrequency ablation. Follow-up with clinic visits, ECG, and Holter monitoring was performed at least every 6 months. A total of 120 consecutive patients (mean age, 29.3±12.7 years; 82% men; all patients with normal ejection fraction) were enrolled. FVT involved left posterior fascicle and left anterior fascicle in 118 and 2 subjects, respectively. VT was noninducible in 3 patients, and ablation was acutely successful in 117 patients. With a median follow-up of 55.7 months, VT of a similar ECG morphology recurred in 17 patients, and repeat procedure confirmed FVT recurrence involving the same fascicle. Shorter VT cycle length was the only significant predictor of FVT recurrence (P=0.03). Six other patients developed new-onset upper septal FVT that was successfully ablated. Conclusions— Ablation of FVT guided by activation mapping is associated with a single procedural success rate without the use of antiarrhythmic drugs of 80.3%. Arrhythmia recurrences after an initially successful ablation were caused by recurrent FVT involving the same fascicle in two thirds of patients or new onset of upper septal FVT in the remainder. PMID:26386017

  4. Wide Complex TachycardiaVentricular Tachycardia or Not Ventricular Tachycardia, That Remains the Question

    PubMed Central

    B Garner, John; M Miller, John

    2013-01-01

    Arriving at the correct diagnosis in cases of wide complex tachycardia remains problematic for many clinicians. In this paper, we review the historical development of criteria used to differentiate among the major diagnostic possibilities and compare the strengths and weaknesses of various differentiating algorithms. PMID:26835036

  5. 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)

  6. Ventricular Tachycardia Following Surgical Repair of Complex Congenital Heart Disease.

    PubMed

    Baysa, Sherrie Joy; Kanter, Ronald J

    2016-03-01

    A nine year old boy with complex congenital heart disease requiring right ventricular outflow tract surgery and palpitations had inducible monomorphic ventricular tachycardia at 300 bpm by programmed ventricular stimulation. He was treated with enteral phenytoin. With a therapeutic plasma level, repeat electrophysiological study was negative for inducible ventricular tachycardia using an aggressive pacing protocol. An insertable loop recorder was implanted, and the family was prescribed an automatic external defibrillator. The decision to not place an implantable cardioverter-defibrillator was based upon anticipated need for serial cardiac MRI scans to monitor the effect of progressive outflow tract stenosis and regurgitation. PMID:26920195

  7. The incidence and morphology of ischaemic ventricular tachycardia.

    PubMed

    Quyyumi, A A; Crake, T; Wright, C; Mockus, L; Levy, R D; Fox, K M

    1986-12-01

    Ventricular arrhythmias are a frequent cause of sudden death in patients with coronary artery disease. The incidence and relationship of ventricular tachycardia to periods of myocardial ischaemia in these patients has not been fully investigated. Ambulatory ST-segment monitoring was performed in 100 consecutive patients with chest pain, of whom 74 had significant coronary artery disease. Recordings were analysed for ST-segment changes and episodes of ventricular tachycardia (greater than 3 beats, rate greater than 100 beats min-1). None of the 26 patients with normal coronary arteries, one of the 22 patients (4.5%) with single vessel disease, one of the 22 patients (4.5%) with double vessel disease and four of the 30 patients (13%) with triple vessel disease, had episodes of non-sustained ventricular tachycardia. Four of these six patients had episodes of reversible ST-segment change but ventricular tachycardia was related to these episodes in only two patients. These two patients had multiple episodes of tachycardia which occurred after the onset of ST-segment change and terminated before the ST-segment returned to baseline; they occurred in clusters with a mean of 12 episodes in each cluster. ST-segment change did not follow episodes of ventricular tachycardia in any patient. The number of ventricular complexes in each episode varied between three and 24 beats and were uniform in three of the six patients. The mean heart rate before the onset of tachycardia was 79 +/- 8 beats per minute and the rate of tachycardia had a mean of 170 +/- 34 beats a minute. Less than 10% of the episodes had a prematurity index of less than 1.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2435552

  8. 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

  9. Severe hypokalemia and thyrotoxic paralysis from painless thyroiditis complicated by life-threatening polymorphic ventricular tachycardia and rhabdomyolysis.

    PubMed

    Chang, Kyung Yoon; Lee, Su-Hyun; Park, Hoon Suk; Ko, Sun-Hee; Ahn, Yu-Bae; Kim, Hyung Wook

    2014-01-01

    A 61-year-old man presented with lower extremity paralysis and severe hypokalemia. His thyroid function test showed thyrotoxicosis. Despite attempts to correct his hypokalemia, he developed pulseless polymorphic ventricular tachycardia two hours later. He was successfully resuscitated after defibrillation. We performed continuous venovenous hemodiafiltration for 10 days due to acute kidney injury and rhabdomyolysis. We observed life-threatening polymorphic ventricular tachycardia requiring urgent defibrillation, as well as rhabdomyolysis requiring dialysis during the transient thyrotoxic phase of painless thyroiditis. Pay attention to the possibility of the development of life-threatening ventricular tachycardia associated with hypokalemia in the setting of thyroiditis and thyrotoxic paralysis. PMID:25130115

  10. Ventricular tachycardia in a patient with the "Chinese restaurant syndrome".

    PubMed

    Gann, D

    1977-07-01

    A 36-year-old man developed severe weakness, palpitation, and diaphoresis 30 minutes after eating wonton soup. On admission to the hospital he was found to have ventricular tachycardia. He was given lidocaine intravenously and the rhythm converted to normal with the three minutes. It was concluded that monosodium L-glutamate might produce potentially serious arrhythmias in susceptible persons. PMID:877655

  11. Electrocardiographic artifact due to a mobile phone mimicking ventricular tachycardia.

    PubMed

    Duan, Xu

    2014-01-01

    A case of electrocardiographic artifact due to mobile a phone mimicking ventricular tachycardia was presented. The artifact was discriminated by close scrutiny of ECG and was attributed to a mobile phone because it was simultaneous with mobile phone game. PMID:24581928

  12. 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

  13. [The clinical and electrophysiological characteristics of patients with idiopathic ventricular tachycardia].

    PubMed

    Iturralde, P; Juárez, U; de Micheli, A; Dorado, M; Alexánderson, E; Colín, L; Kershenovich, S; Romero, L; González Hermosillo, J A

    1992-01-01

    Clinical and electrophysiological characteristics in 20 patients with clinical ventricular tachycardia and normal hearts documented by physical examination, echocardiography, and angiocardiography were analysed. There were 11 males and 9 females. All patients had sustained ventricular tachycardia without hemodynamic instability during tachycardia. A right bundle branch block morphology of ventricular tachycardia was present in 14 patients and left bundle branch block morphology in six patients. During electrophysiologic studies, ventricular tachycardia was induced in 10/15 (66%) patients. Intravenous verapamil terminated the ventricular tachycardia in 9/10 (90%) of cases. However oral verapamil not prevented recurrences. Among 14 patients on whom exercise tests were performed, only two had exercise-induced ventricular/tachycardia. Late potentials were positive in 3/14 (21%) cases and one patient died suddenly during exercise without antiarrhythmic drugs. PMID:1632712

  14. Ventricular Tachycardia in Congenital Pulmonary Stenosis.

    PubMed

    Ruckdeschel, Emily Sue; Schuller, Joseph; Nguyen, Duy Thai

    2016-03-01

    With modern surgical techniques, there is significantly increased life expectancy for those with congenital heart disease. Although congenital pulmonary valve stenosis is not as complex as tetralogy of Fallot, there are many similarities between the 2 lesions, such that patients with either of these conditions are at risk for ventricular arrhythmias and sudden cardiac death. Those patients who have undergone surgical palliation for congenital pulmonary stenosis are at an increased risk for development of ventricular arrhythmias and may benefit from a more aggressive evaluation for symptoms of palpitations or syncope. PMID:26920196

  15. Cardiac Metastasis of Leiomyosarcoma Complicated with Complete Atrio-Ventricular Block and Ventricular Tachycardia

    PubMed Central

    Shin, Jae Ouk; Kim, Minsu; Kang, Woong Chol; Moon, Jeonggeun; Chung, Wook-Jin; Sung, Yon Mi

    2016-01-01

    We described a case of a 54-year-old male who presented with dizziness and dyspnea due to cardiac metastasis of leiomyosarcoma. Cardiac metastasis of leiomyosarcoma caused both bradyarrhythmia and tachyarrhythmia in the patient. He was treated with implantation of a permanent pacemaker for management of complete atrio-ventricular block and anti-arrhythmic drug that suppressed ventricular tachycardia successfully. PMID:27014358

  16. Mitral subannular left ventricular aneurysm. A case presenting with ventricular tachycardia.

    PubMed Central

    Fitchett, D H; Kanji, M

    1983-01-01

    A young African immigrant presented with ventricular tachycardia in association with two mitral subannular left ventricular aneurysms. Although an unusual finding, the recognition of such aneurysms is important as prophylactic measures may prevent complications. Furthermore, they are a surgically treatable cause of heart failure and arrhythmias. Images PMID:6652004

  17. Rotational angiography of left ventricle to guide ventricular tachycardia ablation.

    PubMed

    Wolf, Jiri; Starek, Zdenek; Jez, Jiri; Lehar, Frantisek; Lukasova, Marketa; Kulik, Tomas; Novak, Miroslav

    2015-06-01

    Three-dimensional rotational angiography (3 DRA) is a novel imaging method introduced to guide complex catheter ablations of the left atrium. Our aim was to investigate the feasibility of the method in visualization of left ventricular anatomy and to develop a corresponding protocol for guidance of ventricular tachycardia ablation. We performed 3D rotational angiography in 13 patients using a direct left atrial protocol for data acquisition and the 3D reconstruction of the left ventricle was achieved in all patients. Clinical data comparison has proved lower use of radiation and contrast medium during 3 DRA-guided ablations as compared to CT-guided procedures. PMID:25761532

  18. Ablation of Ventricular Tachycardia in Patients with Ischemic Cardiomyopathy.

    PubMed

    Garabelli, Paul; Stavrakis, Stavros; Po, Sunny S

    2016-03-01

    Ventricular tachycardias (VTs) occurring after prior myocardial infarction are usually caused by reentrant circuits formed by surviving myocardial bundles. Although part of the reentrant circuits may be located in the midmyocardium or epicardium, most of the VTs can be safely and successfully ablated by endocardial ablation targeting the late potentials/local abnormal ventricular activation, which are surrogates for the surviving myocardial bundles. A combination of activation, substrate, pace, and entrainment mapping, as well as the use of contact force catheters, further improves ablation success and safety. PMID:26920180

  19. Detection of false arrhythmia alarms with emphasis on ventricular tachycardia.

    PubMed

    Rodrigues, Rui; Couto, Paula

    2016-08-01

    Our approach to detecting false arrhythmia alarms in the intensive care unit breaks down into several tasks. It involves beat detection on different signals: electrocardiogram, photoplethysmogram and arterial blood pressure. The quality of each channel has to be estimated in order to evaluate the reliability of obtained beat detections. The information about the heart rate from the different channels must be integrated in order to find a final conclusion. Some alarm types require particular detectors as is the case of ventricular fibrillation. To identify false ventricular tachycardia alarms we needed to classify heart beats as normal/ventricular. For that purpose we introduce a new feature, QRS polarity type. This feature was important in order to reduce misclassification of ventricular beats: there was an improvement in the ventricular tachycardia alarm true positive rate from 69% to 81%. However, the true negative rate was reduced from 95% to 69% and our global challenge score (real-time event) dropped from 79.02 to 74.28. Our challenge algorithm achieved the third best score in the 2015 PhysioNet/CinC challenge event 1 (real time). PMID:27454934

  20. Right Ventricular Outflow Tract Tachycardia with Structural Abnormalities of the Right Ventricle and Left Ventricular Diverticulum

    PubMed Central

    Martini, Bortolo; Trevisi, Nicola; Martini, Nicolò; Zhang, Li

    2015-01-01

    A 43-year-old woman presented to the emergency room with a sustained ventricular tachycardia (VT). ECG showed a QRS in left bundle branch block morphology with inferior axis. Echocardiography, ventricular angiography, and cardiac magnetic resonance imaging (CMRI) revealed a normal right ventricle and a left ventricular diverticulum. Electrophysiology studies with epicardial voltage mapping identified a large fibrotic area in the inferolateral layer of the right ventricular wall and a small area of fibrotic tissue at the anterior right ventricular outflow tract. VT ablation was successfully performed with combined epicardial and endocardial approaches. PMID:26509086

  1. Deadly proposal: a case of catecholaminergic polymorphic ventricular tachycardia.

    PubMed

    Heiner, Jason D; Bullard-Berent, Jeffrey H; Inbar, Shmuel

    2011-11-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare adrenergically mediated arrhythmogenic disorder classically induced by exercise or emotional stress and found in structurally normal hearts. It is an important cause of cardiac syncope and sudden death in childhood. Catecholaminergic polymorphic ventricular tachycardia is a genetic cardiac channelopathy with known mutations involving genes affecting intracellular calcium regulation. We present a case of a 14-year-old boy who had cardiopulmonary arrest after an emotionally induced episode of CPVT while attempting to invite a girl to the school dance. Review of his presenting cardiac rhythm, induction of concerning ventricular arrhythmias during an exercise stress test, and genetic testing confirmed the diagnosis of CPVT. He recovered fully and was treated with β-blocker therapy and placement of an implantable cardioverter-defibrillator. In this report, we discuss this rare but important entity, including its molecular foundation, clinical presentation, basics of diagnosis, therapeutic options, and implications of genetic testing for family members. We also compare CPVT to other notable cardiomyopathic and channelopathic causes of sudden death in youth including hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia, long QT syndrome, short QT syndrome, and Brugada syndrome. PMID:22068070

  2. Left Ventricular Aneurysm and Ventricular Tachycardia as Initial Presentation of Cardiac Sarcoidosis

    PubMed Central

    Jmeian, Ashraf; Thawabi, Mohammad; Goldfarb, Irvin; Shamoon, Fayez

    2015-01-01

    Context: Cardiac sarcoidosis (CS) is a rare, potentially fatal disease. It has a wide range of clinical presentations that range from asymptomatic electrocardiogram changes to sudden cardiac death. Ventricular aneurysms and ventricular tachycardia are seen late in the disease, and are rarely the presenting manifestation of the disease. Diagnosis of CS is challenging and often missed or delayed. Case Report: We report a 35-year-old patient who presented with sustained ventricular tachycardia and ST-elevation on electrocardiogram. Cardiac catheterization showed normal coronaries and left ventricular aneurysm. Subsequent 2D-echocardiography showed an infiltrative disease pattern. Cardiac MRI was done and showed late gadolinium enhancement in the septum, apex and lateral wall. The patient was diagnosed with cardiac sarcoidosis and treated with immune suppression and antiarrhythmic agent. In addition underwent AICD implantation. Conclusion: Our case highlights the importance of suspecting cardiac sarcoidosis in young patients presenting with electrocardiogram changes, and present an atypical presentation of this disease. PMID:25839003

  3. Catecholaminergic polymorphic ventricular tachycardia: An exciting new era

    PubMed Central

    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. PMID:27212848

  4. Clinical efficacy of intravenous amiodarone in the short term treatment of recurrent sustained ventricular tachycardia and ventricular fibrillation.

    PubMed Central

    Schützenberger, W; Leisch, F; Kerschner, K; Harringer, W; Herbinger, W

    1989-01-01

    The clinical efficacy of intravenous amiodarone in terminating sustained ventricular tachycardia and in preventing recurrences of ventricular tachycardia and ventricular fibrillation was evaluated in 26 patients. All of them presented with organic heart disease accompanied by depressed left ventricular function. Intravenous amiodarone terminated spontaneous ventricular tachycardia in eight of 19 patients. Fifteen of the 26 patients had had at least one episode of ventricular tachycardia or ventricular fibrillation each day in the period immediately before the intravenous administration of amiodarone. Amiodarone controlled ventricular tachycardia or ventricular fibrillation in nine of these 15 patients; in three further cases it was successful when supplemented by additional administration of a previously ineffective antiarrhythmic drug and ventricular pacing. Two patients died despite these measures. In one, the amiodarone infusion had to be stopped because of an arrhythmogenic effect. Sustained deterioration of haemodynamic function or of pre-existing intraventricular conduction disturbances was never seen. Intravenous amiodarone was effective in terminating sustained ventricular tachycardia and in preventing frequent episodes of ventricular arrhythmia that were refractory to other antiarrhythmic drugs. PMID:2590589

  5. Intramural Reentrant Ventricular Tachycardia in a Patient with Severe Hypertensive Left Ventricular Hypertrophy

    PubMed Central

    Lin, Chin-Yu; Chung, Fa-Po; Lin, Yenn-Jiang

    2015-01-01

    We describe the case of a patient with severe hypertensive left ventricular hypertrophy and sustained hemodynamically unstable ventricular tachycardia (VT). Entrainment was demonstrated in the electrophysiological study. Activation mapping and pacemapping identified the location of the intramural reentrant VT with the exit site close to the epicardium. However, VT persisted after ablation at the epicardial exit site. Successful ablation was performed endocardially at the corresponding position. PMID:26617657

  6. Iatrogenic ‘torsade de pointes’ ventricular tachycardia

    PubMed Central

    Kounis, Nicholas G.

    1979-01-01

    Three patients who developed a distinctive form of ventricular tachycardia with oscillating QRS axis, while they were receiving drugs known to prolong the repolarization time are described. In one of the patients suffering from psychiatric illness and receiving psychotropic drugs the arrhythmia was fatal. It is postulated that the tendency to this arrhythmia was augmented by repeated electric counter shocks and negative bathmotropic drugs. Functional factors may contribute to the pathogenesis of this arrhythmia which seems to constitute an entity. ImagesFig. 1Fig. 2 PMID:523378

  7. Contact dermatitis after implantable cardiac defibrillator implantation for ventricular tachycardia

    PubMed Central

    Dogan, Pinar; Inci, Sinan; Kuyumcu, Mevlut Serdar; Kus, Ozgur

    2016-01-01

    Summary Pacemaker contact sensitivity is a rare condition. Less than 30 reports of pacemaker skin reactions have been described. We report a 57-year-old woman who underwent an implantable cardiac defibrillator (ICD) implantation for ventricular tachycardia. A skin patch test was positive on almost all components of the pacemaker system. She was treated with topical corticosteroids and skin lesions resolved within 2 weeks. Because of widespread use of various devices, we will see this more often and therefore it is important to recognize this problem and its effective management. PMID:26989652

  8. 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

  9. Experimental electrophysiology and arrhythmogenicity. Anisotropy and ventricular tachycardia.

    PubMed

    Allessie, M A; Schalij, M J; Kirchhof, C J; Boersma, L; Huybers, M; Hollen, J

    1989-09-01

    In a 2-D model of anisotropy, created by freezing the intramural and endocardial layers of a Langendorf perfused rabbit heart, sustained ventricular tachycardia (VT) with a cycle length of 130 ms and an excitable gap of 30 ms could be initiated by rapid pacing. High resolution mapping (256 points) of the thin surviving epicardial layer revealed that the VT was based on epicardial re-entry without the involvement of a gross anatomic obstacle and a central line of functional conduction block oriented parallel to the fibre. Microelectrode recordings from the centre of the ellipsoid circuit showed markedly prolonged action potentials, leading to 2:1 or 3:1 cellular responses. At the pivoting points prolonged action potentials with a 1:1 response were recorded. Immediately after termination of VT the same sites showed 1:1 responses with normal action potential duration. The various degrees of prolongation of the action potentials in the centre of functional anisotropic re-entry were caused by electrotonic current flow between the two limbs of the circuit, which were closely opposed but activated with a large time difference. Towards the pivoting points the phase difference between the two limbs of the circuit decreased, but because of slow transverse conduction around the pivoting points was still 30 ms. We conclude that the electrotonic prolongation of the action potentials at the pivoting points of anisotropic re-entry enlarges both the size and the cycle length of the circuit. Anisotropy thus contributes to the creation of stable VT with an excitable gap. PMID:2680500

  10. 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

  11. Ventricular tachycardia in a child with diabetic ketoacidosis without heart disease.

    PubMed

    McGreevy, Megan; Beerman, Lee; Arora, Gaurav

    2016-01-01

    Ventricular tachycardia is uncommon in children without CHD. We present the case of a 15-year-old boy who presented with severe diabetic ketoacidosis and ventricular tachycardia and was not responsive to traditional anti-arrhythmic therapy. This case highlights the importance of identification of the underlying metabolic derangement causing the arrhythmia to provide appropriate management. PMID:26446852

  12. Assessment of a prototype implantable cardioverter for ventricular tachycardia. Relation between synchronisation of sensing and origin of the tachycardia.

    PubMed Central

    Perelman, M S; Rowland, E; Krikler, D M

    1984-01-01

    The feasibility of internal cardioversion for ventricular tachycardia using a prototype of an implantable cardioverter which delivers a low energy discharge via an intracardiac lead and its acceptability to the patient were studied. The cardioverting discharge was synchronised to the apical right ventricular electrogram. In 29 episodes of ventricular tachycardia (RR interval 250-700 ms) the apical electrogram was reliably sensed. The interval from the onset of the QRS complex to the marker of sensing of the electrogram was significantly greater in the 15 episodes arising from the left ventricle than in the 14 episodes arising from the right ventricle; in three cases of ventricular tachycardia arising from the left ventricle the interval exceeded 100 ms. In all cases except one, however, sensing occurred within the first 80% of the QRS complex. In two episodes (RR interval 150 and 190 ms--that is, less than the refractory period of the unit) sensing of the electrogram was unreliable. The unit successfully terminated 10 of 15 episodes of ventricular tachycardia using energies ranging between 0.01 and 1.0 J, but 19 of the 23 discharges delivered to conscious patients caused varying degrees of discomfort. Sensing within 100 ms of the onset of the QRS complex (-20% to 83% of QRS) permitted effective and safe termination of ventricular tachycardia. Although there was neither acceleration of tachycardia nor ventricular fibrillation, subthreshold discharges advanced the next local ventricular electrogram in seven instances. An external low energy cardioverter connected to an intracardiac lead is a useful alternative to repeated external direct current shocks. Images PMID:6477777

  13. Unresponsive ventricular tachycardia associated with aluminum phosphide poisoning.

    PubMed

    Jadhav, Amar P; Nusair, Maein B; Ingole, Apekshe; Alpert, Martin A

    2012-05-01

    Inhalation or ingestion of aluminum phosphide (AP) generates phosphine gas on exposure to moisture, which, in turn, produces widespread organ toxicity primarily involving the lungs, heart, liver, and kidneys. Cardiac manifestations of AP poisoning include toxic myocarditis, refractory heart failure, bradyarrhythmias, and tachyarrhythmias including ventricular tachycardia (VT). A 19-year-old depressed male farm worker ingested ten 500-mg tablets of Celphos in a suicide attempt. Each Celphos tablet contains 56% AP. Over the course of 10 hours, the patient developed heart failure and respiratory failure associated with a rise in serum troponin level to 12.7 ng/mL. Serum electrolytes (including magnesium) and serum creatinine levels were normal throughout. His course was further complicated by acidemia and hypotension. These hemodynamic and metabolic abnormalities were initially corrected by assisted ventilation and continuous veno-venous hemofiltration. However, he developed hemodynamically stable sustained monomorphic VT, which proved unresponsive to treatment with intravenous magnesium sulfate and intravenous amiodarone therapy. After a decline in blood pressure, 6 attempts at electrocardioversion failed to restore sinus rhythm, and he died. Postmortem histologic examination of myocardium showed contraction band necrosis, early coagulation necrosis, edema, hemorrhage, and pyknosis of cardiac myocyte nuclei. Ventricular tachycardia associated with AP poisoning has been successfully treated with magnesium sulfate, amiodarone, and electrocardioversion. This case report documents failure of all 3 of these therapeutic modalities. PMID:21406319

  14. Ventricular fibrillation and tachycardia classification using a machine learning approach.

    PubMed

    Li, Qiao; Rajagopalan, Cadathur; Clifford, Gari D

    2014-06-01

    Correct detection and classification of ventricular fibrillation (VF) and rapid ventricular tachycardia (VT) is of pivotal importance for an automatic external defibrillator and patient monitoring. In this paper, a VF/VT classification algorithm using a machine learning method, a support vector machine, is proposed. A total of 14 metrics were extracted from a specific window length of the electrocardiogram (ECG). A genetic algorithm was then used to select the optimal variable combinations. Three annotated public domain ECG databases (the American Heart Association Database, the Creighton University Ventricular Tachyarrhythmia Database, and the MIT-BIH Malignant Ventricular Arrhythmia Database) were used as training, test, and validation datasets. Different window sizes, varying from 1 to 10 s were tested. An accuracy (Ac) of 98.1%, sensitivity (Se) of 98.4%, and specificity (Sp) of 98.0% were obtained on the in-sample training data with 5 s-window size and two selected metrics. On the out-of-sample validation data, an Ac of 96.3% ± 3.4%, Se of 96.2% ± 2.7%, and Sp of 96.2% ± 4.6% were obtained by fivefold cross validation. The results surpass those of current reported methods. PMID:23899591

  15. [Ablation using radiofrequency in the treatment of ventricular tachycardia].

    PubMed

    Cordero Cabra, J A; Iturralde Torres, P; Lara Vaca, S; Colín Lizalde, L; Kershenovich, S; Carvajal, A; González Hermosillo, J A

    1996-01-01

    We performed radiofrequency catheter ablation in 14 consecutive patients with Ventricular Tachycardia (VT) 10 of which had healthy hearts, one patient with ischemic heart disease, one with arrhythmogenic dysplasia, one with dilated cardiomyopathy, and one with congenital heart disease. The localization of the VT was: 10 in the left posterior fascicular region, 3 in the right ventricular outflow tract (RVOT), and one patient with ischemic heart disease with the substrate in the left ventricular apex. All of them with VT refractory to pharmacological management, using an average of 2.7 drugs per patient. After all patients underwent Electrophysiological Study (EPS), an intracavitary mapping was performed, in order to locate the arrhythmogenic substrate. Later on, the RF ablation was performed, delivering an average of 15 pulses, using 40 Watts, and an average time of 25 sec. per pulse. The procedure was successful in 60% of the fascicular VT, with a 16% of recurrence; 100% of success with those originated in the RVOT with no recurrence; in the ischemic patient we achieved primary success, but with recurrence, a second session was successful with no recurrence up to date. No major complications occurred in this group. Those patients which showed no success required the use of antiarrhythmic drugs. The total success of the series is 71.4% with 10% recurrence, and no mortality. PMID:8967816

  16. Ventricular Tachycardia and Early Fibrillation in Patients With Brugada Syndrome and Ischemic Cardiomyopathy Show Predictable Frequency-Phase Properties on the Precordial ECG Consistent With the Respective Arrhythmogenic Substrate

    PubMed Central

    Calvo, David; Atienza, Felipe; Saiz, Javier; Martínez, Laura; Ávila, Pablo; Rubín, José; Herreros, Benito; Arenal, Ángel; García-Fernández, Javier; Ferrer, Ana; Sebastián, Rafael; Martínez-Camblor, Pablo; Jalife, José

    2015-01-01

    Background— Ventricular fibrillation (VF) has been proposed to be maintained by localized high-frequency sources. We tested whether spectral-phase analysis of the precordial ECG enabled identification of periodic activation patterns generated by such sources. Methods and Results— Precordial ECGs were recorded from 15 ischemic cardiomyopathy and 15 Brugada syndrome (type 1 ECG) patients during induced VF and analyzed in the frequency-phase domain. Despite temporal variability, induced VF episodes lasting 19.6±7.9 s displayed distinctly high power at a common frequency (shared frequency, 5.7±1.1 Hz) in all leads about half of the time. In patients with Brugada syndrome, phase analysis of shared frequency showed a V1–V6 sequence as would be expected from patients displaying a type 1 ECG pattern (P<0.001). Hilbert-based phases confirmed that the most stable sequence over the whole VF duration was V1–V6. Analysis of shared frequency in ischemic cardiomyopathy patients with anteroseptal (n=4), apical (n=3), and inferolateral (n=4) myocardial infarction displayed a sequence starting at V1–V2, V3–V4, and V5–V6, respectively, consistent with an activation origin at the scar location (P=0.005). Sequences correlated with the Hilbert-based phase analysis (P<0.001). Posterior infarction (n=4) displayed no specific sequence. On paired comparison, phase sequences during monomorphic ventricular tachycardia correlated moderately with VF (P<0.001). Moreover, there was a dominant frequency gradient from precordial leads facing the scar region to the contralateral leads (5.8±0.8 versus 5.4±1.1 Hz; P=0.004). Conclusions— Noninvasive analysis of ventricular tachycardia and early VF in patients with Brugada syndrome and ischemic cardiomyopathy shows a predictable sequence in the frequency-phase domain, consistent with anatomic location of the arrhythmogenic substrate. PMID:26253505

  17. Irrigated tip catheters for radiofrequency ablation in ventricular tachycardia.

    PubMed

    Müssigbrodt, Andreas; Grothoff, Matthias; Dinov, Borislav; Kosiuk, Jedrzej; Richter, Sergio; Sommer, Philipp; Breithardt, Ole A; Rolf, Sascha; Bollmann, Andreas; Arya, Arash; Hindricks, Gerhard

    2015-01-01

    Radiofrequency (RF) ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT) ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy. PMID:25705659

  18. Irrigated Tip Catheters for Radiofrequency Ablation in Ventricular Tachycardia

    PubMed Central

    Grothoff, Matthias; Dinov, Borislav; Kosiuk, Jedrzej; Richter, Sergio; Sommer, Philipp; Breithardt, Ole A.; Bollmann, Andreas; Arya, Arash; Hindricks, Gerhard

    2015-01-01

    Radiofrequency (RF) ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT) ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy. PMID:25705659

  19. Bidirectional ventricular tachycardia with myocardial infarction: a case report with insight on mechanism and treatment.

    PubMed

    Wase, Abdul; Masood, Abdul-Mannan; Garikipati, Naga V; Mufti, Omar; Kabir, Anwarul

    2014-01-01

    Bidirectional ventricular tachycardia (BVT) is a rare variety of tachycardia with morphologically distinct presentation: The QRS axis and/or morphology is alternating in the frontal plane leads. Since its original description in association with digitalis,(1) numerous cases of this fascinating tachycardia with disparate etiologies and mechanisms have been postulated. We report a patient with BVT in association with non-ST elevation myocardial infarction and severe cardiomyopathy in the absence of digoxin toxicity. PMID:25173208

  20. [Recurrent ventricular tachycardia as a late complication of a cardiac stab wound].

    PubMed

    Niedziela, Justyna; Wozakowska-Kapłon, Beata; Dziubek, Katarzyna; Jaskulska-Niedziela, Elzbieta; Włosowicz, Monika

    2010-01-01

    We present a case of a 55-year-old male who suffered from a cardiac stab wound in his youth and 38 years later developed unstable sustained ventricular tachycardia. Imaging showed presence of a scarf of myocardium which probably caused the arrhythmia. Arrhythmia was successfully controlled using combined treatment with pharmacotherapy and cardioverter-defibrillator implantation. Relapses of ventricular tachycardia treated by appropriate interventions of cardioverter-defibrillator occurred when the patient stopped pharmacotherapy and experienced great psychic stress. PMID:20131201

  1. Implantation of the new Medtronic LINQ™ loop recorder in an infant with ventricular tachycardia.

    PubMed

    Hutchinson, Lisa J; Stuart, Graham; Walsh, Mark A

    2015-08-01

    The Medtronic LINQ™ was inserted in an 11-month-old boy for close monitoring of rapid ventricular tachycardia. The device is much smaller than the conventional Medtronic loop recorder. The real advantage of the LINQ™ is that it automatically notifies Carelink if any ventricular tachycardia is seen, which is very advantageous for this particular type of patient. This device is ideal for close monitoring of asymptomatic yet potentially dangerous arrhythmias in smaller children. PMID:25341443

  2. Changes in autonomic activity preceding onset of nonsustained ventricular tachycardia

    NASA Technical Reports Server (NTRS)

    Osaka, M.; Saitoh, H.; Sasabe, N.; Atarashi, H.; Katoh, T.; Hayakawa, H.; Cohen, R. J.

    1996-01-01

    Background: The triggering role of the autonomic nervous system in the initiation of ventricular tachycardia has not been established. To investigate the relationship between changes in autonomic activity and the occurrence of nonsustained ventricular tachycardia (NSVT) we examined heart rate variability (HRV) during the 2-hour period preceding spontaneous episodes of NSVT. Twenty-four subjects were identified retrospectively as having had one episode of NSVT during 24-hour Holter ECC recording. Methods: We measured the mean interval between normal heats (meanRR), the standard deviation of the intervals between beats (SD), the percentage of counts of sequential intervals between normal beats with a change of >50 ms (%RR50), the logarithms of low- and high-frequency spectral components (lnLF, lnHF) of HRV for sequential 10-minute segments preceding NSVT. The correlation dimension (CDim) of HRV was calculated similarly for sequential 20-minute segments. We assessed the significance of the time-course change of each marker over the 120-minute period prior to NSVT onset. Results: MeanRR (P < 0.05), lnLF (P < 0.0001), lnHF (P < 0.0001), the natural logarithm of the ratio of LF to HF (ln[LF/HF]; P < 0.05), and CDim (P < 0.05) showed significant time-course changes during that period, while SD and %RR50 did not. MeanRR, lnLF, lnHF, and CDim all decreased prior to the onset of NSVT, whereas ln(LF/HF) increased. We divided the subjects into two groups: one consisting of 12 patients with coronary artery disease; and the second group of 12 patients without known coronary artery disease. Both groups showed significant changes (P < 0.05) of CDim, lnLF, and lnHF preceding the episodes of NSVT. Conclusions: Changes in the pattern of HRV prior to the onset of episodes of NSVT suggest that changes in autonomic activity may commonly play a role in the triggering of spontaneous episodes of NSVT in susceptible patients. The measured changes suggest a reduction in parasympathetic

  3. Anomalous coronary artery causing transmural ischaemia and ventricular tachycardia in a high school athlete.

    PubMed

    Vianna, Caio Brito; Gonzalez, Maria Margarita; Dallan, Luis Alberto; Shiozaki, Afonso Akio; Medeiros, Fabio Morais; Britto, Pedro Carrusca; Cesar, Luiz Antonio

    2007-07-01

    A previously asymptomatic 15-year-old boy was treated at our institution after an episode of chest pain, palpitation, and syncope while playing in a high school soccer game. The patient's resting electrocardiogram was normal. A transthoracic echocardiogram showed an anomalous left main coronary artery originating from the right sinus of Valsalva. Contrast-enhanced multidetector computed tomography demonstrated clearly that the anomalous vessel coursed between the aorta and the pulmonary trunk (interarterial subtype). Treadmill testing registered several nonsustained polymorphic ventricular tachycardias and transmural myocardial ischaemia in the early recovery phase (ST-elevation up to 5mm in CM5 and V2 leads). The patient underwent bypass grafting. One year later, he remains asymptomatic, and new treadmill tests have been normal. In this patient, severe transmural myocardial ischaemia was detected, possibly due to collapse or vasospasm of the anomalous vessel, triggering life-threatening ventricular arrhythmias. PMID:17353080

  4. Comparative electrophysiological effects of captopril or hydralazine combined with nitrate in patients with left ventricular dysfunction and inducible ventricular tachycardia.

    PubMed Central

    Bashir, Y; Sneddon, J F; O'Nunain, S; Paul, V E; Gibson, S; Ward, D E; Camm, A J

    1992-01-01

    OBJECTIVE--To assess the electrophysiological and antiarrhythmic effects of pharmacological load manipulation by an angiotensin converting enzyme (ACE) inhibitor (captopril) and a direct vasodilator (hydralazine plus isosorbide mononitrate) in patients with inducible ventricular tachycardia and impaired left ventricular function. DESIGN--Randomised open label cross-over comparison of three regimens. SETTING--Tertiary arrhythmia referral centre. SUBJECTS--Eight patients with reduced left ventricular function and sustained ventricular tachycardia inducible by programmed stimulation. INTERVENTIONS--Three treatment regimens each of 48 hours duration: captopril, hydralazine plus isosorbide mononitrate, and control (no vasodilator). MAIN OUTCOME MEASURES--Changes in central haemodynamics, electrophysiological parameters, and induction of ventricular tachycardia during treatment with captopril, or hydralazine combined with nitrate, compared with a control period. RESULTS--Both vasodilator treatments produced similar balanced reductions in peak systolic pressures and filling pressures compared with controls. Captopril had no effect on sinus cycle length, atrial refractoriness, or intraventricular conduction, but prolonged ventricular effective and functional refractory periods and QT interval during constant rate atrial pacing. Hydralazine combined with nitrate did not significantly alter any electrophysiological variable. Ventricular tachycardia was similarly inducible during all three periods. CONCLUSIONS--Load manipulation by captopril but not hydralazine combined with nitrate prolonged ventricular refractoriness and repolarisation, possibly reflecting a combination of mechano-electrical effect with the restraining influence of ACE inhibitors on reflex sympathetic stimulation. PMID:1389714

  5. Mismatch Between Cardiac Perfusion, Sympathetic Innervation, and Left Ventricular Electroanatomical Map in a Patient with Recurrent Ventricular Tachycardia

    PubMed Central

    Jungen, Christiane; von Gogh, Gwendolyn; Schmitt, Christiane; Kuklik, Pawel; Hoffmann, Boris; Nakajima, Kenichi; Willems, Stephan; Mester, Janos; Meyer, Christian

    2016-01-01

    Patient: Male, 69 Final Diagnosis: Recurrent ventricular tachycardia Symptoms: Multiple ICD shocks Medication: — Clinical Procedure: Ventricular tachycardia ablation Specialty: Cardiology Objective: Rare co-existance of disease or pathology Background: Regional cardiac sympathetic denervation causes electrophysiological heterogeneity and has been found to be a predictor of potentially lethal VT. Case Report: We present the case of 69-year-old patient admitted with recurrent ventricular tachycardia and a history of anterior myocardial infarction. In line with Tc-99m-MIBI-SPECT perfusion imaging, electroanatomical mapping revealed extensive LV anterior scarring as detected by low-voltage areas. Surprisingly, I-123-MIBG-SPECT showed an extensive deficit of sympathetic innervation inferior (mismatch) and anterolateral (match). Conclusions: Combination of electroanatomical mapping with tomographic imaging of innervation and perfusion might improve our understanding of the neural trigger of VT after myocardial infarction or substrate-based catheter ablation. PMID:27109542

  6. Sustained Ventricular Tachycardia in Apparently Normal Hearts: Ablation Should Be the First Step in Management.

    PubMed

    Moss, Joshua D; Tung, Roderick

    2016-09-01

    Patients without structural heart disease tend to have fewer morphologies of ventricular tachycardia, with automaticity and triggered activity a more common mechanism than re-entry associated with extremely low risk of sudden death. Ablation can be curative in patients with a single morphology of ventricular tachycardia that is focal in origin, particularly in patients without overt structural heart disease. There are limited data in secondary prevention implantable cardioverter defibrillator literature to support the routine implementation of implantable cardioverter defibrillator in normal hearts. Antiarrhythmic drugs have not been shown to reduce all-cause mortality in patients with and without structural heart disease. PMID:27521095

  7. What happens to people with 'supra' ventricular tachycardia?

    PubMed

    Campbell, R W

    1994-04-01

    Nothing in arrhythmia management should be taken for granted. Errors and mistakes over the last 30 years must now force reappraisal of the arrhythmia risks and the risk-benefits of their treatment. Supraventricular tachycardias have attracted great interest from electrophysiologists and the fundamental mechanisms of many are now well established. Surprisingly, however, very little is known of the long-term implications of supraventricular tachycardias in terms of quality and quantity of life. Not even for asymptomatic WPW syndrome is there consensus in this regard. The extent of our deficiencies in knowledge need to be appreciated and more must be done to understand the natural history of these events. PMID:8070494

  8. Ventricular tachycardia from intracardiac hematoma in the setting of blunt thoracic trauma.

    PubMed

    Solhpour, Amirreza; Ananaba-Ekeruo, Ijeoma; Memon, Nada B; Kantharia, Bharat K

    2014-01-01

    In the victims of motor vehicle accidents, unrecognized myocardial injuries may pose diagnostic and therapeutic challenges. Herein, we present a case of a 17-year-old man who developed multiple ventricular premature complexes and nonsustained ventricular tachycardia in the setting of blunt chest trauma from a motor vehicle accident. We discuss significance of the electrocardiographic abnormalities in making an accurate diagnosis of cardiac hematoma and its management. PMID:24581106

  9. Relationship Between MDCT‐Imaged Myocardial Fat and Ventricular Tachycardia Substrate in Arrhythmogenic Right Ventricular Cardiomyopathy

    PubMed Central

    Komatsu, Yuki; Jadidi, Amir; Sacher, Frederic; Denis, Arnaud; Daly, Matthew; Derval, Nicolas; Shah, Ashok; Lehrmann, Heiko; Park, Chan‐Il; Weber, Reinhold; Arentz, Thomas; Pache, Gregor; Sermesant, Maxime; Ayache, Nicholas; Relan, Jatin; Montaudon, Michel; Laurent, François; Hocini, Mélèze; Haïssaguerre, Michel; Jaïs, Pierre; Cochet, Hubert

    2014-01-01

    Background Myocardial fibrofatty infiltration is a milieu for ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy (ARVC) and can be depicted as myocardial hypodensity on contrast‐enhanced multidetector computed tomography (MDCT) with high spatial and temporal resolution. This study aimed to assess the relationship between MDCT‐imaged myocardial fat and VT substrate in ARVC. Methods and Results We studied 16 patients with ARVC who underwent ablation and preprocedural MDCT. High‐resolution imaging data were processed and registered to high‐density endocardial and epicardial maps in sinus rhythm on 3‐dimensional electroanatomic mapping (3D‐EAM) (626±335 and 575±279 points/map, respectively). Analysis of the locations of low‐voltage and fat segmentation included the following endocardial and epicardial regions: apex, mid (anterior, lateral, inferior), and basal (anterior, lateral, inferior). The location of local abnormal ventricular activities (LAVA) was compared with fat distribution. RV myocardial fat was successfully segmented and integrated with 3D‐EAM in all patients. The κ agreement test demonstrated a good concordance between the epicardial low voltage and fat (κ=0.69, 95% CI 0.54 to 0.84), but fair concordance with the endocardium (κ=0.41, 95% CI 0.27 to 0.56). The majority of LAVA (520/653 [80%]) were located within the RV fat segmentation, of which 90% were not farther than 20 mm from its border. Registration of MDCT allowed direct visualization of the coronary arteries, thus avoiding coronary damage during epicardial radiofrequency delivery. Conclusions The integration of MDCT‐imaged myocardial fat with 3D‐EAM provides valuable information on the extent and localization of VT substrate and demonstrates ablation targets clustering in its border region. PMID:25103203

  10. 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

  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. Bundle branch reentrant tachycardia in a patient with normal ventricular function.

    PubMed

    Fynn, Simon P; Kalman, Jonathan M

    2004-06-01

    We report an unusual case of bundle branch reentrant tachycardia, in a patient with normal left ventricular function, cured by radiofrequency catheter ablation. However, the long-term prognosis of these patients is uncertain. We discuss the indications for an implantable defibrillator in this group. PMID:15133364

  13. Intra-QT Spectral Coherence as a Possible Noninvasive Marker of Sustained Ventricular Tachycardia

    PubMed Central

    Piccirillo, Gianfranco; Moscucci, Federica; Di Barba, Daniele; Pappadà, Maria Antonella; Rossi, Pietro; Quaglione, Raffaele; Barillà, Francesco; Magrì, Damiano

    2014-01-01

    Sudden cardiac death is the main cause of mortality in patients affected by chronic heart failure (CHF) and with history of myocardial infarction. No study yet investigated the intra-QT phase spectral coherence as a possible tool in stratifying the arrhythmic susceptibility in patients at risk of sudden cardiac death (SCD). We, therefore, assessed possible difference in spectral coherence between the ECG segment extending from the q wave to the T wave peak (QTp) and the one from T wave peak to the T wave end (Te) between patients with and without Holter ECG-documented sustained ventricular tachycardia (VT). None of the QT variability indexes as well as most of the coherences and RR power spectral variables significantly differed between the two groups except for the QTp-Te spectral coherence. The latter was significantly lower in patients with sustained VT than in those without (0.508 ± 0.150 versus 0.607 ± 0.150, P < 0.05). Although the responsible mechanism remains conjectural, the QTp-Te spectral coherence holds promise as a noninvasive marker predicting malignant ventricular arrhythmias. PMID:25133170

  14. An unusual cause of ventricular tachycardia: Port-A-Cath fracture and embolization into the pulmonary artery.

    PubMed

    Wassef, Anthony W A; Kass, Malek; Parmar, Gurpreet; Ravandi, Amir

    2014-01-01

    We describe the case of a patient with a previously placed Port-A-Cath who was admitted to hospital for new onset of non-flushing catheter and palpitations with ventricular tachycardia. A chest X-ray and a linogram showed a Port-A-Cath fracture and distal embolization into the right ventricle resulting in ventricular tachycardia. The catheter was removed percutaneously using a Goose Neck snare with no complications and resolution of the ventricular tachycardia. The removed segment demonstrated thrombus. Prompt removal of the embolized catheter fragments should be undertaken given the subtle nature of the embolization and the potential complications. PMID:27004095

  15. Bundle-branch reentry ventricular tachycardia after transcatheter aortic valve replacement

    PubMed Central

    de la Rosa Riestra, Adriana; Rubio Caballero, José Amador; Freites Estévez, Alfonso; Alonso Belló, Javier; Botas Rodríguez, Javier

    2016-01-01

    An 83-year-old male suffering from severe symptomatic aortic valve stenosis received an implant of a biological aortic prosthesis through the femoral artery without complications. Seven days after dischargement he experienced a syncope. The patient was wearing an ECG holter monitor that day, which showed a wide QRS complex tachycardia of 300 beats per minute. The electrophysiological study revealed a bundle-branch reentry ventricular tachycardia as the cause of the syncope. Radio-frequency was applied on the right-bundle branch. Twelve months later, the patient has remained asymptomatic. PMID:27134443

  16. Nonsustained Ventricular Tachycardia in the Normal Heart: Risk Stratification and Management.

    PubMed

    Marine, Joseph E

    2016-09-01

    Nonsustained ventricular tachycardia (NSVT) may trigger concern, particularly in patients with known congestive heart failure, structural heart disease, or prolonged QT interval. When NSVT occurs in patients with normal hearts, it usually has a benign prognosis. Therefore, establishing the presence or absence of structural or inherited heart disease is a critical step in each patient's evaluation. It is important to approach a wide-complex tachycardia in a systematic manner, to ensure correct diagnosis and treatment. When NSVT occurs in a patient with a normal heart, treatment is targeted toward symptoms and may consist of observation, medical therapy, or catheter ablation. PMID:27521087

  17. Mitral Subvalvular Aneurysm in a Patient with Chagas Disease and Recurrent Episodes of Ventricular Tachycardia

    PubMed Central

    Grillo, Tereza Augusta; Athayde, Guilherme Rafael S.; Belfort, Ana Flávia L.; Miranda, Reynaldo C.; Beaton, Andrea Z.; Nascimento, Bruno R.

    2015-01-01

    Subvalvular left ventricular aneurysm is a rare disease of obscure origin suggesting unique causes such as congenital, traumatic, and inflammatory or infectious diseases. Its mortality is closely related to heart failure, mitral insufficiency, thromboembolic phenomena, and cardiac arrhythmias. Although association with coronary artery disease is not described, the compression of epicardial vessels by the aneurysm may lead to ischemic manifestations. We report here a case of mitral subvalvular left ventricular aneurysm of probable chagasic origin, in a patient with normal left ventricular function evolving with repeated episodes of monomorphic ventricular tachycardia, despite noninducible electrophysiological testing and the use of optimal medical treatment, including amiodarone. The indication for implantable cardioverter-defibrillator in patients with Chagas cardiomyopathy and segmental wall motion abnormalities but without global systolic dysfunction remains unclear in literature, even in the presence of complex ventricular arrhythmias. A brief review of the literature on morphological features, diagnosis, prognosis, and treatment will be also discussed. PMID:26634158

  18. Incessant tachycardia in a patient with advanced heart failure and left ventricular assist device: What is the mechanism?

    PubMed

    Noheria, Amit; Mulpuru, Siva K; Noseworthy, Peter A; Asirvatham, Samuel J

    2016-01-01

    We present a case of incessant wide-complex tachycardia in a patient with left-ventricular assist device, and discuss the differential diagnosis with an in-depth analysis of the intracardiac tracings during the invasive electrophysiologic study, including interpretation of the relative timing of the fascicular signals during tachycardia and in sinus rhythm, and interpretation of pacing and entrainment maneuvers. PMID:27485564

  19. Phenytoin as an effective treatment for polymorphic ventricular tachycardia due to QT prolongation in a patient with multiple drug intolerances.

    PubMed

    Yager, Neil; Wang, Katherine; Keshwani, Najiba; Torosoff, Mikhail

    2015-01-01

    We present a case of a 69-year-old woman presenting with polymorphic ventricular tachycardia caused by QT prolongation. Owing to known intolerances to a majority of antiarrhythmic medications, one remaining option was to initiate phenytoin. Phenytoin's narrow therapeutic window, multiple drug interactions and side effect profile make it an infrequently used antiarrhythmic. It is, however, a potent antiarrhythmic agent, which may be useful in treatment of ventricular tachycardia, especially in patients with multiple drug intolerances. PMID:26071440

  20. The role of antiarrhythmic therapy in the management of nonsustained ventricular tachycardia.

    PubMed

    Gomes, J A

    1999-11-01

    The incidence of nonsustained ventricular tachycardia (NSVT) after myocardial infarction (MI), has decreased significantly in the thrombolytic era and may not have a high enough power to predict sudden cardiac death or all-cause mortality post-MI. Nonetheless, noninvasive algorithms that utilize the combination of NSVT with left ventricular dysfunction, abnormal signal-averaged electrocardiogram, and heart rate variability can be used for better risk assessment. Recent multicenter studies have provided strong evidence for the use of an implantable cardioverter defibrillator in patients with NSVT and inducible sustained ventricual tachycardia. On the other hand anti-arrhythmic drugs have no role and most are harmful in asymptomatic patients post-MI with NSVT. PMID:10980857

  1. Idiopathic intrafascicular reentrant left ventricular tachycardia in an elite cyclist athlete.

    PubMed

    Riera, Andrés Ricardo Pérez; Ragognete, Ricardo Gitti; Filho, Celso Ferreira; Ferreira, Marcelo; Schapachnik, Edgardo; Dubner, Sergio; Ferreira, Celso; Mochon, Agnieszka; Zhang, Li

    2009-01-01

    A 32 year-old Caucasian male, an elite athlete, was admitted to the emergency department because of a sudden onset of palpitations which had lasted more than 12 hours and were associated with chest discomfort. He had a two-year history of recurrent stress-induced palpitations. He denied either episodes of syncope or any family history of sudden death. Physical examination was normal. He had no evidence of structural heart disease. The electrocardiography (ECG) documented during the event supported the diagnosis of idiopathic reentrant left ventricular tachycardia. Ventricular tachycardia ablation was successful. This case demonstrates that a careful physical examination and correct ECG diagnosis can lead to an appropriate arrhythmia management. PMID:19950094

  2. Ventricular Tachycardia Arising from Cardiac Crux: Electrocardiogram Recognition and Site of Ablation.

    PubMed

    Larroussi, Leila; Badhwar, Nitish

    2016-03-01

    This case highlights idiopathic ventricular tachycardia (VT) arising from the crux of the heart. It is seen in patients without structural heart disease and can present as rapid hemodynamically unstable VT leading to cardiac arrest. 12 lead ECG showing RBBB with Q waves in inferior leads, precordial MDI>0.55 and R

  3. An Intracardiac Mass in a Pregnant Woman Presenting With Ventricular Tachycardia.

    PubMed

    Alimi, Hedieh; Samiei, Niloufar; Madadi, Shabnam; Zare, Asghar; Azizian, Nasrin; Chitsazan, Mitra; Mozaffari, Kambiz; Yousefnia, Mohammad Ali; Kashfi, Fahimeh

    2016-06-01

    A pregnant patient presented with symptomatic ventricular tachycardia. Echocardiography revealed a large intramyocardial mass. Surgical resection was attempted in conjunction with cryoablation of the surrounding myocardial tissue. Histologic examination of the resected mass revealed cardiac neurofibroma. To the best of our knowledge, this is the first report of cardiac neurofibroma in a pregnant patient in the absence of any neurocutaneous syndromes such as neurofibromatosis. PMID:27211956

  4. 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

  5. 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

  6. Electrophysiological mapping and radiofrequency catheter ablation for ventricular tachycardia in a patient with peripartum cardiomyopathy.

    PubMed

    Tokuda, Michifumi; Stevenson, William G; Nagashima, Koichi; Rubin, David A

    2013-11-01

    A 38-year-old female with prior failed endocardial ablation for ventricular tachycardia (VT) was referred for further treatment. She had been diagnosed with peripartum cardiomyopathy 7 years before and had persistent left ventricular dysfunction with an ejection fraction of 20%. Epicardial voltage mapping showed extensive epicardial scar despite absence of endocardial scar. Five distinct VT morphologies were induced. Ablation was aided by electrogram characteristics, pace mapping, entrainment mapping, and establishing electrical inexcitability along areas of epicardial scar. After epicardial ablation no sustained VT was induced. She had been doing well without VT occurrence but died 1 year later unexpectedly at home. PMID:24102817

  7. Outcomes of Catheter Ablation of Ventricular Tachycardia in the Setting of Structural Heart Disease.

    PubMed

    Betensky, B P; Marchlinski, F E

    2016-07-01

    Sustained ventricular tachycardias are common in the setting of structural heart disease, either due to prior myocardial infarction or a variety of non-ischemic etiologies, including idiopathic dilated cardiomyopathy, hypertrophic cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy. Over the past two decades, percutaneous catheter ablation has evolved dramatically and has become an effective tool for the control of ventricular arrhythmias. Single and multicenter observational studies as well as several prospective randomized trials have begun to investigate long-term outcomes after catheter ablation procedures. These studies encompass a wide range of mapping and ablation techniques, including conventional activation mapping/entrainment criteria, substrate modification guided by pacemapping, late potential and abnormal electrogram ablation, scar de-channeling, and core isolation. While large-scale, multicenter prospective randomized clinical trials are somewhat limited, the published data demonstrate favorable outcomes with respect to a reduction in overall ventricular tachycardia (VT) burden, reduction of implantable cardioverter defibrillator (ICD) shocks, and discontinuation of anti-arrhythmic medications across varying disease subtypes and convincingly support the use of catheter ablation as the standard of care for many patients with VT in the setting of structural heart disease. PMID:27234813

  8. Focal Monomorphic Ventricular Tachycardia As The First Manifestation Of Amyloid Cardiomyopathy

    PubMed Central

    Seethala, Srikanth; Jain, Sandeep; Ohori, N. Paul; Monaco, Sara; Lacomis, Joan; Crock, Frederick; Nemec, Jan

    2010-01-01

    52-year-old patient presented with palpitation and well tolerated monomorphic ventricular tachycardia. He had normal echocardiogram and coronary angiogram 3 months prior to presentation. Surface EKG revealed regular wide-complex tachycardia with right bundle branch block morphology and right inferior axis. In conjunction with recent negative cardiac evaluation, this suggested idiopathic focal ventricular tachycardia from anterolateral basal left ventricle. CARTO based activation mapping confirmed the presence of VT focus in that area. Radiofrequency ablation at the site of perfect pacemap resulted in a partial suppression of the focus. Echocardiogram was subsequently performed because of progressive dyspnea. It revealed asymmetrical thickening of posterolateral left ventricle, with delayed enhancement on contrast magnetic resonance imaging. Fine needle aspiration of abdominal fat stained with Congo red confirmed the diagnosis of systemic AL amyloidosis due to IgG λ-light chain deposition. Consequently, the patient underwent placement of implantable defibrillator and hematopoetic stem cell transplantation. He remains in excellent functional status 18 months after presentation. PMID:20234811

  9. [Non-pharmacological treatment of ventricular tachycardia (anti-arrhythmic surgery excluded)].

    PubMed

    Touboul, P

    1993-05-01

    There has been real change in the treatment of VT in recent years including the promotion of non-medical methods. In the large group of non-responders to medical therapy, only a minority offers possibilities of radical surgical treatment of VT. In the others, two options remain: ablative methods and implantable automatic cardioverter defibrillators. The destruction of foci of tachycardia by catheterisation necessitates prior investigation of the ventricular endocardium with recordings of endocardial electrograms during VT. Criteria defining the zone for ablation are two-fold: either the zone of earliest endocardial depolarisation or the exit zone (generally preceding the tachycardia QRS complexes by 20 to 30 ms). The second is the zone of slow conduction which corresponds to the cardiac substrate in which the tachycardia arises. In the absence of satisfactory mapping, localisation of the ablation target may be performed by stimulating the endocardium at different points with the aim of reproducing the tachycardia QRS complexes. Two types of physical agents have been used for ablation: high energy electric shocks and, at present, radiofrequency currents. Complications of the procedure are rare: thromboembolism, cardiac rupture, cardiogenic shock in patients with initially poor hemodynamic conditions. Prevention of VT is obtained in over half the cases providing complementary antiarrhythmic therapy is prescribed. The other alternative is the implantable automatic defibrillator which is tending to take over the leading role in non-pharmacological treatment of VT. At first, these devices were exclusively defibrillators but nowadays they have anti-tachycardia functions which widen the indications to include subjects with sustained VT even in the absence of cardiac arrest.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8267510

  10. Automatic Supporting System for Regionalization of Ventricular Tachycardia Exit Site in Implantable Defibrillators

    PubMed Central

    Sanromán-Junquera, Margarita; Mora-Jiménez, Inmaculada; Almendral, Jesús; García-Alberola, Arcadio; Rojo-Álvarez, José Luis

    2015-01-01

    Electrograms stored in Implantable Cardioverter Defibrillators (ICD-EGM) have been proven to convey useful information for roughly determining the anatomical location of the Left Ventricular Tachycardia exit site (LVTES). Our aim here was to evaluate the possibilities from a machine learning system intended to provide an estimation of the LVTES anatomical region with the use of ICD-EGM in the situation where 12-lead electrocardiogram of ventricular tachycardia are not available. Several machine learning techniques were specifically designed and benchmarked, both from classification (such as Neural Networks (NN), and Support Vector Machines (SVM)) and regression (Kernel Ridge Regression) problem statements. Classifiers were evaluated by using accuracy rates for LVTES identification in a controlled number of anatomical regions, and the regression approach quality was studied in terms of the spatial resolution. We analyzed the ICD-EGM of 23 patients (18±10 EGM per patient) during left ventricular pacing and simultaneous recording of the spatial coordinates of the pacing electrode with a navigation system. Several feature sets extracted from ICD-EGM (consisting of times and voltages) were shown to convey more discriminative information than the raw waveform. Among classifiers, the SVM performed slightly better than NN. In accordance with previous clinical works, the average spatial resolution for the LVTES was about 3 cm, as in our system, which allows it to support the faster determination of the LVTES in ablation procedures. The proposed approach also provides with a framework suitable for driving the design of improved performance future systems. PMID:25910170

  11. Outflow Tract Premature Ventricular Contractions and Ventricular Tachycardia: The Typical and the Challenging.

    PubMed

    John, Roy M; Stevenson, William G

    2016-09-01

    The ventricular outflow tracts are the most common sites of origin for ventricular arrhythmias that occur in the absence of structural heart disease. Drug therapy with β-blockers and calcium blockers has limited efficacy for control. In the presence of marked symptoms or frequent arrhythmia causing left ventricular (LV) dysfunction, catheter ablation is a consideration. The right ventricular outflow tract, aortic root, LV outflow endocardium, and epicardium are potential sites for ablation for these arrhythmias. In intractable cases of highly symptomatic ventricular arrhythmias originating from the LV summit, surgical ablation is an option. PMID:27521088

  12. Fetal ventricular tachycardia secondary to long QT syndrome treated with maternal intravenous magnesium: case report and review of the literature.

    PubMed

    Simpson, J M; Maxwell, D; Rosenthal, E; Gill, H

    2009-10-01

    Ventricular tachycardia is a very rare fetal arrhythmia accounting for fewer than 2% of fetal tachycardias. We describe a fetus presenting at 30 weeks' gestation with ventricular tachycardia at a rate of 220 beats per min and fetal hydrops. The tachycardia was unresponsive to flecainide but was controlled within 12 h by an intravenous infusion of magnesium to the mother. Despite rapid control of the arrhythmia the fetus developed severe periventricular leukomalacia before birth for which a poor neurological prognosis was given. The baby was delivered preterm at 32 weeks' gestation and died on the sixth day after birth. Long QT syndrome was identified postnatally on the electrocardiogram, and was confirmed by genetic testing which showed a mutation in the KCNH2 gene (p.T613M). PMID:19731233

  13. Pulseless Ventricular Tachycardia During Office-Based Anesthetic in a Four-Year-Old Child

    PubMed Central

    Orr, Timothy M.; Orr, Daniel L.

    2015-01-01

    A 4-year-old 16-kg boy presented for full mouth dental rehabilitation in a private pediatric dental office. The patient had no significant previous medical history. Upon sevoflurane induction by a dentist anesthesiologist, the patient converted from normal sinus rhythm to pulseless ventricular tachycardia. Advanced cardiac life support protocol was initiated. After 2 automatic external defibrillator shocks were delivered in conjunction with epinephrine administration, the patient returned to normal sinus rhythm. The patient was transported via emergency medical service paramedics to a local children's hospital emergency room where he was observed uneventfully for 24 hours prior to discharge. PMID:26650495

  14. Anatomic Guidance For Ablation: Atrial Flutter, Fibrillation, and Outflow Tract Ventricular Tachycardia

    PubMed Central

    Sehar, Nandini; Mears, Jennifer; Bisco, Susan; Patel, Sandeep; Lachman, Nirusha; Asirvatham, Samuel J

    2010-01-01

    After initial documentation of excellent efficacy with radiofrequency ablation, this procedure is being performed increasingly in more complex situations and for more difficult arrhythmia. In these circumstances, an accurate knowledge of the anatomic basis for the ablation procedure will help maintain this efficacy and improve safety. In this review, we discuss the relevant anatomy for electrophysiology interventions for typical right atrial flutter, atrial fibrillation, and outflow tract ventricular tachycardia. In the pediatric population, maintaining safety is a greater challenge, and here again, knowing the neighboring and regional anatomy of the arrhythmogenic substrate for these arrhythmias may go a long way in preventing complications. PMID:20811537

  15. Ventricular tachycardia initiated by high energy cardioversion in a patient with an implantable cardioverter defibrillator.

    PubMed Central

    Chinushi, M.; Aizawa, Y.; Higuchi, K.

    1997-01-01

    A transvenous implantable cardioverter defibrillator (ICD) was implanted into a 58 year old woman with idiopathic dilated cardiomyopathy who had drug refractory monomorphic ventricular tachycardia (VT). Antitachycardia pacing failed to terminate the VT; termination was attempted at 24 J, which was above the defibrillation threshold. When cardioversion at 24 J was delivered, VT with a different morphology and slower rate was reproducibly initiated. At 3 J, however, the original VT was successfully terminated without initiation of the slower VT. A new VT may be induced by high energy cardioversion. This may be a manifestation of the proarrhythmic potential of ICDs. PMID:9155621

  16. Verapamil-sensitive idiopathic left ventricular tachycardia in a 6-month-old: unique considerations in diagnosis and management in an infant.

    PubMed

    Hiremath, Gurumurthy; Li, Walter; Foltz, Rhonda; Roy-Burman, Arup; Cocalis, Mark; Tanel, Ronn E

    2015-01-01

    Idiopathic left ventricular tachycardia of the Belhassen type is rare in infants. We present a 6-month-old infant girl with a wide-complex tachycardia with right bundle branch block QRS morphology, a superior axis, and atrioventricular dissociation, consistent with a left anterior fascicular tachycardia. Initial echocardiogram revealed depressed ventricular function. The tachycardia was unresponsive to therapeutic trials of adenosine, esmolol, procainamide, and lidocaine. There was brief conversion of the tachycardia to sinus rhythm with transesophageal atrial overdrive pacing, suggesting a reentrant mechanism of the arrhythmia. Ultimately, the judicious administration of intravenous verapamil resulted in termination of the arrhythmia, which has been sustained on oral therapy. PMID:25526021

  17. Sotalol: a rescue drug in the face of life-threatening refractory ventricular tachycardia.

    PubMed

    Kandasamy, Ashok; Arumugham, Sukumar; Krupanandha, Harshavardhan; Reddy, Bhaktavatsala

    2014-01-01

    We describe postoperative refractory ventricular tachycardia (VT) in a patient following aortic and mitral valve replacement. Following an uneventful separation from cardiopulmonary bypass with dobutamine, the patient developed recurrent VT, 4 hours into the postoperative period. The VT did not respond to standard doses of xylocard, magnesium and amiodarone. Electrolyte and acid base parameters were normal. Multiple cardioversions failed to revert back to a stable rhythm. Intra-aortic balloon pumping was instituted and overdrive right ventricular pacing was unsuccessful. Following intravenous sotalol 80 mg, the VT came under control and reverted to a nodal rhythm, which required atrial pacing for the next 8 hours. Oral sotalol therapy was continued at 40 mg daily. The VT did not recur. PMID:24732625

  18. Effects of verapamil on ventricular tachycardias possibly caused by reentry, automaticity, and triggered activity.

    PubMed Central

    Sung, R J; Shapiro, W A; Shen, E N; Morady, F; Davis, J

    1983-01-01

    To define the role of verapamil in the treatment of ventricular tachycardia (VT), we studied 21 patients with chronic recurrent VT. Electrophysiologic studies were performed before and during intravenous infusion of verapamil (0.15 mg/kg followed by 0.005 mg/kg per min). On the basis of the mode of VT initiation and termination, we identified three groups of patients: (a) 11 patients had VT suggestive of reentry, as VT could be initiated with ventricular extrastimulation and terminated with overdrive ventricular pacing. Verapamil did not affect the inducibility and cycle length of VT. (b) 7 patients had VT suggestive of catecholamine-sensitive automaticity as VT could not be initiated with programmed electrical stimulation but could be provoked by isoproterenol infusion. Moreover, the VT could not be converted to a sustained sinus rhythm with overdrive ventricular pacing and it resolved only with discontinuing isoproterenol infusion. Verapamil exerted no effects on VT. (c) 3 patients had VT with electrophysiologic characteristics suggestive of triggered activity related to delayed afterdepolarizations. Characteristically, after attaining a range of cycle lengths, the sinus, atrial or ventricular paced rhythm could initiate VT without ventricular extrastimulation. The first beat of VT invariably occurred late in the cardiac cycle with a premature coupling interval 0-80 ms shorter than the preceding QRS cycle length; the premature coupling interval gradually decreased as the sinus, atrial or ventricular paced cycle length progressively shortened. Of note, verapamil completely suppressed VT inducibility in these three patients. These observations lead us to suggest that verapamil does not affect VT caused by reentry and catecholamine-sensitive automaticity but is effective in suppressing VT caused by triggered activity related to delayed afterdepolarizations in humans. PMID:6874951

  19. 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

  20. Ventricular tachycardia

    MedlinePlus

    ... Symptoms may include: Chest discomfort ( angina ) Fainting (syncope) Light-headedness or dizziness Sensation of feeling the heart beat ( palpitations ) Shortness of breath Symptoms may start and stop suddenly. In some cases, there are no symptoms.

  1. 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

  2. Effects of Flecainide on Exercise-Induced Ventricular Arrhythmias and Recurrences in Genotype-Negative Patients with Catecholaminergic Polymorphic Ventricular Tachycardia

    PubMed Central

    Watanabe, Hiroshi; van der Werf, Christian; Roses-Noguer, Ferran; Adler, Arnon; Sumitomo, Naokata; Veltmann, Christian; Rosso, Raphael; Bhuiyan, Zahurul A.; Bikker, Hennie; Kannankeril, Prince J.; Horie, Minoru; Minamino, Tohru; Viskin, Sami; Knollmann, Björn C.; Till, Jan; Wilde, Arthur A.M.

    2013-01-01

    Background Conventional therapy with β-blockers is incompletely effective in preventing arrhythmic events in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). We have previously discovered that flecainide in addition to conventional drug therapy prevents ventricular arrhythmias in genotype-positive CPVT patients. Objective To study the efficacy of flecainide in genotype-negative CPVT patients. Methods We studied the efficacy of flecainide for reducing ventricular arrhythmias during exercise testing and preventing arrhythmia events during long-term follow-up. Results Twelve genotype-negative CPVT patients were treated with flecainide. Conventional therapy failed to control ventricular arrhythmias in all patients. Flecainide was initiated because of significant ventricular arrhythmias (n=8), syncope (n=3), or cardiac arrest (n=1). At the baseline exercise test before flecainide, 6 patients had ventricular tachycardia and 5 patients had bigeminal or frequent ventricular premature beats. Flecainide reduced ventricular arrhythmias at the exercise test in 8 patients compared to conventional therapy, similarly to genotype-positive patients in our previous report. Notably, flecainide completely prevented ventricular arrhythmias in 7 of the patients. Flecainide was continued in all patients except for one who had ventricular tachycardia at the exercise test on flecainide. During a follow-up of 48±94 months, arrhythmia events (sudden cardiac death and aborted cardiac arrest) associated with noncompliance occurred in two patients. Flecainide was not discontinued due to side effects in any of the patients. Conclusion Flecainide was effective in genotype-negative CPVT patients, suggesting that spontaneous Ca2+ release from ryanodine channels plays a role in arrhythmia susceptibility, similarly to genotype-positive patients. PMID:23286974

  3. Insights into the mechanism of idiopathic left ventricular tachycardia: a case report and literature review.

    PubMed

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

    2015-01-01

    Left ventricular posterior fascicular tachycardia (LVPFT) is an idiopathic form of VT characterized by right bundle branch block morphology and left axis deviation. The mechanism of LPFVT is thought to be localized reentry close to the posterior fascicle. We present the case of a 24-year-old medical student who was admitted to the emergency department complaining of palpitations. The ECG showed an aspect suggestive of LVPFT. Vagal maneuvers, adenosine and i.v. Metoprolol were ineffective in terminating the arrhythmia. Conversion to sinus rhythm was obtained 10 h later, with i.v Amiodarone. The ECG in sinus rhythm showed left posterior fascicular block. Because antiarrhythmic drugs were not desired by the patient, VT ablation was proposed. The electrophysiological study identified the mechanism of arrhythmia to be reentry using the slowly conducting verapamil-sensitive fibers as the antegrade limb and the posterior fascicle as the retrograde limb. Radiofrequency applications near the posterior fascicle, in the lower half of the interventricular septum, at the junction of the two proximal thirds with the distal third interrupted the tachycardia and made it non-inducible at programmed stimulation. The case is unusual as the patient had a left posterior fascicular block during sinus rhythm before ablation. This demonstrates that the reentry circuit of VT does not need antegrade conduction through the posterior fascicle for perpetuation. PMID:26381389

  4. Digoxin Therapy of Fetal Superior Ventricular Tachycardia: Are Digoxin Serum Levels Reliable?

    PubMed Central

    Saad, Antonio F.; Monsivais, Luis; Pacheco, Luis D.

    2016-01-01

    Background  Despite its seldom occurrence, fetal tachycardia can lead to poor fetal outcomes including hydrops and fetal death. Management can be challenging and result in maternal adverse effects secondary to high serum drug levels required to achieve effective transplacental antiarrhythmic drug therapy. Case  A 33-year-old woman at 33 weeks of gestation with a diagnosis of a fetal sustained superior ventricular tachycardia developed chest pain, shortness of breath, and bigeminy on electrocardiogram secondary to digoxin toxicity despite subtherapeutic serum drug levels. She required supportive care with repletion of corresponding electrolyte abnormalities. After resolution of cardiac manifestations of digoxin toxicity, the patient was discharged home. The newborn was discharged at day 9 of life on maintenance amiodarone. Conclusion  We describe an interesting case of digoxin toxicity with cardiac manifestations of digoxin toxicity despite subtherapeutic serum drug levels. This case report emphasizes the significance of instituting an early diagnosis of digoxin toxicity during pregnancy, based not only on serum drug levels but also on clinical presentation. In cases of refractory supportive care, digoxin Fab fragment antibody administration should be considered. With timely diagnosis and treatment, excellent maternal and perinatal outcomes can be achieved. PMID:27516921

  5. Management of patients with ventricular tachycardia in Europe: results of the European Heart Rhythm Association survey.

    PubMed

    Chen, Jian; Todd, Derick M; Proclemer, Alessandro; Sciaraffia, Elena; Estner, Heidi L; Broadhurst, Paul; Blomström-Lundqvist, Carina

    2015-08-01

    The purpose of this European Heart Rhythm Association (EHRA) survey was to assess clinical practice in the management of ventricular tachycardia (VT). The data are based on an electronic questionnaire sent to the members of the EHRA Research Network. Responses were received from 31 centres in 16 countries. The results of the survey show that the management of VT is in general in accordance with guidelines. Antiarrhythmic drugs are still frequently used for VT treatment. In patients at high risk of sudden cardiac death, an implantable cardioverter-defibrillator is routinely recommended, while the treatment options vary for patients with moderate or low risk. A discreet attitude is adopted for catheter ablation in high-risk patients as demonstrated by a relatively low rate of catheter ablation. PMID:26273104

  6. Catheter Ablation of Ventricular Tachycardia in Patients with Post-Infarction Cardiomyopathy

    PubMed Central

    Nazer, Babak

    2014-01-01

    Monomorphic ventricular tachycardia (VT) in patients with post-infarction cardiomyopathy (CMP) is caused by reentry through slowly conducting tissue with in areas of myocardial scar. The use of implantable cardioverter-defibrillators (ICDs) has helped to decrease the risk of arrhythmic death in patients with post-infarction CMP, but the symptomatic and psychological burden of ICD shocks remains significant. Experience with catheter ablation has progressed substantially in the past 20 years, and is now routinely used to treat patients with post-infarction CMP who experience VT or receive ICD therapy. Depending on the hemodynamic tolerance of VT, a variety of mapping techniques may be used to identify sites for catheter ablation, including activation and entrainment mapping for mappable VTs, or substrate mapping for unmappable VTs. In this review, we discuss the pathophysiology of VT in post-infarction CMP patients, and the contemporary practice of catheter ablation. PMID:25089131

  7. Early detection of ventricular tachycardia with sending messages to cell phone

    NASA Astrophysics Data System (ADS)

    Ramirez, L. J.; Lozano, F. A.; Rondon, C. R.

    2011-09-01

    Sustained ventricular tachycardia (VTs) can be asymptomatic for some people, but for other is deadly because it is a major cause of sudden cardiac death [1]. Some patients may present this arrhythmia, and even so, they decide to drive car increasing the likelihood of VTs, putting at risk not only his life but that of the other drivers. We developed a system for early detection of VTs, consisting of EKG sensors, a card of processing and a cell phone, which detects this arrhythmia, gives an alarm signal to the driver, and it simultaneously sending to text messages a specialist doctor and a relative or friend, all in real time. This design was conditioned to the car, is light and comfortable, that allowed that work of car's driver without discomfort. This system will save lives, since in case of emergency sends a help message, no matter where you are in the driver.

  8. Rare presentation of intralobar pulmonary sequestration associated with repeated episodes of ventricular tachycardia

    PubMed Central

    Rao, D Sheshagiri; Barik, Ramachandra

    2016-01-01

    Arterial supply of an intralobar pulmonary sequestration (IPS) from the coronary circulation is extremely rare. A significant coronary steal does not occur because of dual or triple sources of blood supply to sequestrated lung tissue. We present a 60-year-old woman who presented to us with repeated episodes of monomorphic ventricular tachycardia (VT) in last 3 mo. Radio frequency ablation was ineffective. On evaluation, she had right lower lobe IPS with dual arterial blood supply, i.e., right pulmonary artery and the systemic arterial supply from the right coronary artery (RCA). Stress myocardial perfusion scan revealed significant inducible ischemia in the RCA territory. Coronary angiogram revealed critical stenosis of proximal RCA just after the origin of the systemic artery supplying IPS. The critical stenosis in the RCA was stented. At 12 mo follow-up, she had no further episodes of VT or angina. PMID:27468336

  9. Long-term Outcomes of Ventricular Tachycardia Ablation in Different Types of Structural Heart Disease

    PubMed Central

    Liang, Jackson J; Santangeli, Pasquale; Callans, David J

    2015-01-01

    Ventricular tachycardia (VT) often occurs in the setting of structural heart disease and can affect patients with ischaemic or nonischaemic cardiomyopathies. Implantable cardioverter-defibrillators (ICDs) provide mortality benefit and are therefore indicated for secondary prevention in patients with sustained VT, but they do not reduce arrhythmia burden. ICD shocks are associated with increased morbidity and mortality, and antiarrhythmic medications are often used to prevent recurrent episodes. Catheter ablation is an effective treatment option for patients with VT in the setting of structural heart disease and, when successful, can reduce the number of ICD shocks. However, whether VT ablation results in a mortality benefit remains unclear. We aim to review the long-term outcomes in patients with different types of structural heart disease treated with VT ablation. PMID:26835122

  10. Rare presentation of intralobar pulmonary sequestration associated with repeated episodes of ventricular tachycardia.

    PubMed

    Rao, D Sheshagiri; Barik, Ramachandra

    2016-07-26

    Arterial supply of an intralobar pulmonary sequestration (IPS) from the coronary circulation is extremely rare. A significant coronary steal does not occur because of dual or triple sources of blood supply to sequestrated lung tissue. We present a 60-year-old woman who presented to us with repeated episodes of monomorphic ventricular tachycardia (VT) in last 3 mo. Radio frequency ablation was ineffective. On evaluation, she had right lower lobe IPS with dual arterial blood supply, i.e., right pulmonary artery and the systemic arterial supply from the right coronary artery (RCA). Stress myocardial perfusion scan revealed significant inducible ischemia in the RCA territory. Coronary angiogram revealed critical stenosis of proximal RCA just after the origin of the systemic artery supplying IPS. The critical stenosis in the RCA was stented. At 12 mo follow-up, she had no further episodes of VT or angina. PMID:27468336

  11. New Family With Catecholaminergic Polymorphic Ventricular Tachycardia Linked to the Triadin Gene.

    PubMed

    Rooryck, Caroline; Kyndt, Florence; Bozon, Dominique; Roux-Buisson, Nathalie; Sacher, Frederic; Probst, Vincent; Thambo, Jean-Benoit

    2015-10-01

    We describe a new family with cathecholaminergic polymorphic ventricular tachycardia (CPVT) linked to the Triadin gene. This is the second report of such a CPVT of autosomal recessive inheritance. Using an NGS panel including 42 genes involved in cardiac sudden death, 2 heterozygous pathogenic mutations (c.613C> T/p.Gln205* and c.22 + 29 A>G) were identified in the Triadin gene in 2 sibs who experienced early severe arrhythmias without evidence of CPVT diagnosis at first cardiac evaluation. However, significant arrhythmias occurred after catecholaminergic stimulation. Each of the TRDN mutations was inherited from a healthy parent. In this family, genetic studies permit confirmation of the CPVT diagnosis in the 2 affected sibs and permit the early diagnosis of the third asymptomatic child. It also helped guide the therapeutic strategy in this family. PMID:26200674

  12. Long-Term Outcome of Non-Sustained Ventricular Tachycardia in Structurally Normal Hearts

    PubMed Central

    Lin, Chin-Yu; Chang, Shih-Lin; Chung, Fa-Po; Chen, Yun-Yu; Lin, Yenn-Jiang; Lo, Li-Wei; Hu, Yu-Feng; Tuan, Ta-Chuan; Chao, Tze-Fan; Liao, Jo-Nan; Chang, Yao-Ting; Lin, Chung-Hsing; Allamsetty, Suresh; Walia, Rohit; Te, Abigail Louise D.; Yamada, Shinya; Chiang, Shuo-Ju; Tsao, Hsuan-Ming; Chen, Shih-Ann

    2016-01-01

    Background The impact of non-sustained ventricular tachycardia (NSVT) on the risk of thromboembolic event and clinical outcomes in patients without structural heart disease remains undetermined. This study aimed to evaluate the association between NSVT and clinical outcomes. Methods The study population of 5903 patients was culled from the “Registry of 24-hour ECG monitoring at Taipei Veterans General Hospital” (REMOTE database) between January 1, 2002 and December 31, 2004. Of that total, we enrolled 3767 patients without sustained ventricular tachycardia, structural heart disease, and permanent pacemaker. For purposes of this study, NSVT was defined as 3 or more consecutive beats arising below the atrioventricular node with an RR interval of <600 ms (>100 beats/min) and lasting < 30 seconds. Result There were 776 deaths, 2042 hospitalizations for any reason, 638 cardiovascular (CV)-related hospitalizations, 350 ischemic strokes, 409 transient ischemic accident (TIA), 368 new-onset heart failure (HF), and 260 new-onset atrial fibrillation (AF) with a mean follow-up duration of 10 ± 1 years. In multivariate analysis, the presence of NSVT was independently associated with death (hazard ratio [HR]: 1.362, 95% confidence interval [CI]: 1.071–1.731), CV hospitalization (HR: 1.527, 95% CI: 1.171–1.992), ischemic stroke (HR: 1.436, 95% CI: 1.014–2.032), TIA (HR 1.483, 95% CI: 1.069–2.057), and new-onset HF (HR: 1.716, 95% CI: 1.243–2.368). There was no significant association between the presence of NSVT and all-cause hospitalization or new-onset AF. Conclusion In patients without structural heart disease, presence of NSVT on 24-hour monitoring was independently associated with death, CV hospitalization, ischemic stroke, TIA, and new onset heart failure. PMID:27548469

  13. Relation of magnetocardiographic arrhythmia risk parameters to delayed ventricular conduction in postinfarction ventricular tachycardia.

    PubMed

    Korhonen, Petri; Pesola, Katja; Järvinen, Antero; Mäkijärvi, Markku; Katila, Toivo; Toivonen, Lauri

    2002-09-01

    Time-domain late field and intra-QRS fragmentation parameters in magnetocardiography (MCG) identify patients prone to VT after myocardial infarction. This study investigated if they are related to slow ventricular conduction and affected by arrhythmia surgery. Twenty-two patients with old myocardial infarction undergoing map-guided subendocardial resection to treat sustained VT were included. Bipolar electrograms were recorded during operation using an epicardial jacket and endocardial balloon electrode array. The time from the QRS onset to the end of local ventricular excitation in each electrogram was measured during sinus rhythm. Multi-channel MCG was recorded before and after operation and filtered QRS duration (QRSd), root mean square amplitude of the magnetic field strength during the last 40 ms of the QRS complex (RMS40), duration of the low amplitude signal < 300 fT (LAS300), fragmentation index M (M), and fragmentation score S (S) were determined. All patients had one or two VT foci localized and resected. MCG parameters correlated with time to the latest end of ventricular excitation; r = 0.45 for QRSd (P = 0.035), r = 0.64 for M (P = 0.001), and r = 0.73 for S (P < 0.001). The correlations were even better in patients with anterior infarction (e.g., r = 0.87 for QRSd, P < 0.001; r = 0.91 for M, P < 0.001). The operation reduced the abnormalities in MCG parameters and 20 of the 21 patients tested postoperatively became noninducible. MCG parameters indicating postinfarction arrhythmia propensity are related to delayed ventricular conduction. Abolition of the arrhythmia substrate reverses the abnormality of these parameters. PMID:12380770

  14. Predicting the effect of D,L-sotalol on ventricular tachycardia inducibility from the RR variability response

    PubMed Central

    Brembilla-Perrot, B; Houriez, P; Claudon, O; Preiss, J; Beurrier, D

    1999-01-01

    AIM—To find a rapid way of identifying non-responders to D,L-sotalol in patients with ventricular tachycardia.
METHODS—Programmed ventricular stimulation and RR variability were studied in the control state and 10 days after treatment with 160 to 320 mg of D,L-sotalol in 36 consecutive patients with ventricular tachycardia.
RESULTS—In 14 patients (group I) D,L-sotalol suppressed ventricular tachycardia inducibility. In 22 patients (group II) sustained ventricular tachycardia remained inducible during D,L-sotalol treatment. The ventricular tachycardia rate was slowed in eight patients and unchanged or accelerated in 14. At baseline, heart rate variability was similar in both groups. During treatment with D,L-sotalol, variables reflecting parasympathetic activity (pNN50, rMSSD, and high frequency amplitude (HF)) increased in both groups: HF increased from (mean (SD)) 75 (68) to 146 (134) in group I (p < 0.05) and from 60 (49) to 125 (79) in group II (p < 0.05). Other variables were unchanged in group I. In group II, the variables associated with sympathetic activity (coefficient of variance (CV), ratio of low frequency amplitude (LF) to HF) decreased significantly: CV decreased from 13 (4) to 9 (2) (p < 0.001) and LF/HF from 4.74 (3.02) to 3.00 (2.02) (p < 0.05).
CONCLUSIONS—The β blocking effect of D,L-sotalol produced a significant improvement over control values in indices of parasympathetic tone in all treated patients. However, the heart rate variability indices related to sympathetic activity were decreased only in non-responders. This effect of D,L-sotalol on heart rate variability could help detect non-responders to the drug and avoid an electrophysiological study.


Keywords: sotalol; ventricular tachycardia; heart rate variability PMID:10455080

  15. Comparison of left ventricular ejection fraction and inducible ventricular tachycardia in ST-elevation myocardial infarction treated by primary angioplasty versus thrombolysis.

    PubMed

    Chong, James J H; Ganesan, Anand N; Eipper, Vicki; Kovoor, Pramesh

    2008-01-15

    Electrophysiologic studies predict the risk for sudden death after myocardial infarction (MI). Although primary angioplasty has become the preferred method of treatment for ST-elevation MI, intravenous thrombolysis remains the first-line treatment in 30% to 70% of cases worldwide. Rates of ventricular tachyarrhythmias may vary according to type of reperfusion treatment. This study was undertaken to examine the hypothesis that the left ventricular ejection fraction (LVEF) and rates of inducible ventricular tachycardia may be more favorable in treatment with primary angioplasty rather than thrombolysis. Consecutive patients receiving primary angioplasty (n = 225) or thrombolysis (n = 195) for ST-elevation MI were included. The mean LVEF was 48 +/- 12% for the primary angioplasty group and 46 +/- 13% for the thrombolysis group (p = 0.30). The proportion of patients with LVEFs <40% was 30% in the primary angioplasty group and 30% in the thrombolysis group (p = 0.98). Patients with LVEFs <40% underwent electrophysiologic studies. Ventricular tachycardia was inducible in 23 of 66 primary angioplasty patients (34.8%) compared with 21 of 55 (38.1%) thrombolysis patients (p = 0.69). Implantable cardiac defibrillators were inserted in 30 patients, of whom 8 (27%) had appropriate device activations. The mean time from MI to first spontaneous activation was 387 +/- 458 days. In conclusion, patients treated with thrombolysis or primary angioplasty for ST-elevation MIs had similar resultant LVEFs and rates of inducible ventricular tachycardia. There was a surprisingly high rate of spontaneous defibrillator activations, often occurring late after MI. PMID:18178398

  16. Prediction of Ventricular Tachycardia One Hour before Occurrence Using Artificial Neural Networks.

    PubMed

    Lee, Hyojeong; Shin, Soo-Yong; Seo, Myeongsook; Nam, Gi-Byoung; Joo, Segyeong

    2016-01-01

    Ventricular tachycardia (VT) is a potentially fatal tachyarrhythmia, which causes a rapid heartbeat as a result of improper electrical activity of the heart. This is a potentially life-threatening arrhythmia because it can cause low blood pressure and may lead to ventricular fibrillation, asystole, and sudden cardiac death. To prevent VT, we developed an early prediction model that can predict this event one hour before its onset using an artificial neural network (ANN) generated using 14 parameters obtained from heart rate variability (HRV) and respiratory rate variability (RRV) analysis. De-identified raw data from the monitors of patients admitted to the cardiovascular intensive care unit at Asan Medical Center between September 2013 and April 2015 were collected. The dataset consisted of 52 recordings obtained one hour prior to VT events and 52 control recordings. Two-thirds of the extracted parameters were used to train the ANN, and the remaining third was used to evaluate performance of the learned ANN. The developed VT prediction model proved its performance by achieving a sensitivity of 0.88, specificity of 0.82, and AUC of 0.93. PMID:27561321

  17. Prediction of Ventricular Tachycardia One Hour before Occurrence Using Artificial Neural Networks

    PubMed Central

    Lee, Hyojeong; Shin, Soo-Yong; Seo, Myeongsook; Nam, Gi-Byoung; Joo, Segyeong

    2016-01-01

    Ventricular tachycardia (VT) is a potentially fatal tachyarrhythmia, which causes a rapid heartbeat as a result of improper electrical activity of the heart. This is a potentially life-threatening arrhythmia because it can cause low blood pressure and may lead to ventricular fibrillation, asystole, and sudden cardiac death. To prevent VT, we developed an early prediction model that can predict this event one hour before its onset using an artificial neural network (ANN) generated using 14 parameters obtained from heart rate variability (HRV) and respiratory rate variability (RRV) analysis. De-identified raw data from the monitors of patients admitted to the cardiovascular intensive care unit at Asan Medical Center between September 2013 and April 2015 were collected. The dataset consisted of 52 recordings obtained one hour prior to VT events and 52 control recordings. Two-thirds of the extracted parameters were used to train the ANN, and the remaining third was used to evaluate performance of the learned ANN. The developed VT prediction model proved its performance by achieving a sensitivity of 0.88, specificity of 0.82, and AUC of 0.93. PMID:27561321

  18. The investigation and management of broad complex tachycardia and ventricular standstill presenting in pregnancy: A case report

    PubMed Central

    Slater, Tom A; Sainsbury, Paul A

    2014-01-01

    A 23 year old pregnant lady at 35 weeks gestation presented to accident and emergency with worsening dyspnoea, palpitations and dizziness. Twelve lead electrocardiogram, routine bloods and echocardiography were normal. Ambulatory monitoring previously had shown an episode of monomorphic broad complex tachycardia (BCT) and a short episode of ventricular standstill. She was admitted for cardiac monitoring until delivery. Several episodes of ventricular standstill and self-terminating BCT were recorded, which were not associated with symptoms. The patient's symptoms either corresponded with sinus rhythm or supraventricular tachycardia. She underwent elective caesarean section at 37 weeks with no complications. The patient's symptoms reduced considerably post delivery, and she was discharged three days later. Unfortunately she then had a presyncopal episode whilst holding her baby. Due to concern regarding the safety of her baby she had a permanent pacemaker implanted to allow safe beta-blockade. She remains asymptomatic six months later.

  19. Sustained Ventricular Tachycardia in Apparently Normal Hearts: Medical Therapy Should be the First Step in Management.

    PubMed

    Saeid, Ali Kazemi; Klein, George J; Leong-Sit, Peter

    2016-09-01

    Sustained monomorphic ventricular tachycardia or repetitive premature ventricular complexes can be seen in patients with structurally normal hearts. Among these types of patients, the prognosis is predominantly benign and the treatment mostly focused on elimination of symptoms rather than improving survival or reduction of mortality. This article focuses on the pharmacologic options for management and compares them with invasive options. Based on the current literature, we demonstrate that medical therapies should be used as first-line management and favored over invasive therapies. Understanding the arrhythmia mechanism is critical in choosing the appropriate medication among the wide variety of antiarrhythmic drugs available. PMID:27521096

  20. Ventricular Tachycardia and Resembling Acute Coronary Syndrome During Pheochromocytoma Crisis: A Case Report.

    PubMed

    Li, Shi-Jun; Wang, Tao; Wang, Lin; Pang, Zhan-Qi; Ma, Ben; Li, Ya-Wen; Yang, Jian; Dong, He

    2016-04-01

    Pheochromocytomas are neuroendocrine tumors, and its cardiac involvement may include transient myocardial dysfunction, acute coronary syndrome (ACS), and even ventricular arrhythmias.A patient was referred for evaluation of stuttering chest pain, and his electrocardiogram showed T-wave inversion over leads V1 to V4. Coronary angiography showed 90% stenosis in the mid-left anterior descending coronary artery (LAD), which was stented. Five days later, the patient had ventricular tachycardia, and severe hypertension, remarkable blood pressure fluctuation between 224/76 and 70/50 mm Hg. The patient felt abdominal pain and his abdominal ultrasound showed suspicious right adrenal gland tumor. Enhanced computed tomography of adrenal gland conformed that there was a tumor in right adrenal gland accompanied by an upset level of aldosterone.The tumor was removed by laparoscope, and the pathological examination showed pheochromocytoma. After the surgery, the blood pressure turned normal gradually. There was no T-wave inversion in lead V1-V4. Our case illustrates a rare pheochromocytoma presentation with a VT and resembling ACS. In our case, the serious stenosis in the mid of LAD could be explained by worsen the clinical course of myocardial ischemia or severe coronary vasospasm by the excessive amounts of catecholamines released from the tumor. Coronary vasospasm was possible because he had no classic coronary risk factors (e.g. family history and smoking habit, essential hypertension, hyperglycemia and abnormal serum lipoprotein, high body mass index). Thus, pheochromocytoma was missed until he revealed the association of his symptoms with abdominalgia.As phaeochromocytomas that present with cardiovascular complications can be fatal, it is necessary to screen for the disease when patients present with symptoms indicating catecholamine excess. PMID:27057898

  1. Efficacy of procainamide on ventricular tachycardia: relation to prolongation of refractoriness and slowing of conduction.

    PubMed

    Furukawa, T; Rozanski, J J; Moroe, K; Gosselin, A J; Lister, J W

    1989-10-01

    The effect of procainamide on intraventricular conduction and refractoriness, and the prevention of induction of ventricular tachycardia (VT) were studied in 29 patients who had remote myocardial infarction and inducible sustained monomorphic VT. AFter intravenous administration of 15 mg/kg procainamide, induction of VT was suppressed in seven (24%) patients (responders), while in 22 (76%) VT was still inducible (nonresponders). The percent change in paced QRS duration at a cycle length (CL) of 400 msec produced by procainamide was significantly less in responders than in nonresponders: 29.8 +/- 3.9% versus 38.9 +/- 10.8% (p = 0.0020). The percent change in the right ventricular effective refractory period (ERP) at CLs of 600 and 400 msec was significantly greater in responders than in nonresponders: 14.6 +/- 6.9% versus 7.9 +/- 7.3% (p = 0.0414) for ERP at a CL of 600 msec and 15.1 +/- 7.0% versus 8.0 +/- 7.4% (p = 0.0386) for ERP at a CL of 400 msec. Stepwise discriminant analysis showed that greater percent increase in ERP at a CL of 400 msec and lesser percent increase in paced QRS duration at a CL of 400 msec were significantly independent markers for the responders. These findings suggest that lesser slowing of conduction and greater prolongation of refractoriness by procainamide tend to abolish reentry within the reentrant circuit. Greater slowing of conduction and lesser prolongation of refractoriness tend to stabilize a reentrant circuit, and promote the continued induction of VT. PMID:2801477

  2. A swine model of infarct-related reentrant ventricular tachycardia: Electroanatomic, magnetic resonance, and histopathological characterization

    PubMed Central

    Tschabrunn, Cory M.; Roujol, Sébastien; Nezafat, Reza; Faulkner-Jones, Beverly; Buxton, Alfred E.; Josephson, Mark E.; Anter, Elad

    2016-01-01

    BACKGROUND Human ventricular tachycardia (VT) after myocardial infarction usually occurs because of subendocardial reentrant circuits originating in scar tissue that borders surviving myocardial bundles. Several preclinical large animal models have been used to further study postinfarct reentrant VT, but with varied experimental methodologies and limited evaluation of the underlying substrate or induced arrhythmia mechanism. OBJECTIVE We aimed to develop and characterize a swine model of scar-related reentrant VT. METHODS Thirty-five Yorkshire swine underwent 180-minute occlusion of the left anterior descending coronary artery. Thirty-one animals (89%) survived the 6–8-week survival period. These animals underwent cardiac magnetic resonance imaging followed by electrophysiology study, detailed electroanatomic mapping, and histopathological analysis. RESULTS Left ventricular (LV) ejection fraction measured using CMR imaging was 36% ± 6.6% with anteroseptal wall motion abnormality and late gadolinium enhancement across 12.5% ± 4.1% of the LV surface area. Low voltage measured using endocardial electroanatomic mapping encompassed 11.1% ± 3.5% of the LV surface area (bipolar voltage ≤1.5 mV) with anterior, anteroseptal, and anterolateral involvement. Reentrant circuits mapped were largely determined by functional rather than fix anatomical barriers, consistent with “pseudo-block” due to anisotropic conduction. Sustained monomorphic VT was induced in 28 of 31 swine (90%) (67 VTs; 2.4 ± 1.1; range 1–4) and characterized as reentry. VT circuits were subendocardial, with an arrhythmogenic substrate characterized by transmural anterior scar with varying degrees of fibrosis and myocardial fiber disarray on the septal and lateral borders. CONCLUSION This is a well-characterized swine model of scar-related subendocardial reentrant VT. This model can serve as the basis for further investigation in the physiology and therapeutics of humanlike postinfarction

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

    PubMed Central

    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. PMID:26114861

  4. Management of tachycardia

    PubMed Central

    Olshansky, Brian

    2015-01-01

    Tachycardia, conventionally, but arbitrarily, defined as an atrial and/or ventricular rate of >100 beats per minute, is encountered commonly and can be physiological or pathological in origin. Various adverse consequences from tachycardia have been recognized, and an important one is the association between persistent tachycardia and cardiomyopathy. In this article, we provide an up-to-date review on the etiology of tachycardia, management strategies, and the prognosis of patients presenting with tachycardia and cardiomyopathy. PMID:26097733

  5. [Ventricular pre-excitation revealed by idioventricular rhythm and large QRS tachycardias. Apropos of an operated case].

    PubMed

    Weissenburger, J; Dumoulin, P; Juliard, J M; Frank, R; Kessler, P; Michel, P L; Rozensztajn, L; Valty, J

    1983-06-01

    A 15 year old boy presented with palpitations of sudden onset and termination over a two month period. The heart was clinically and radiologically normal. The electrocardiogramme showed sinus rhythm with a short PR interval (0,11 sec) and narrow QRS complexes (0,08 sec) associated with an intermittent escape accelerated idioventricular rhythm (AIVR). During an attack of palpitations a regular tachycardia (250/min) with wide QRS complexes of the same configuration as those of the AIVR (left side delay). The diagnosis of ventricular tachycardia was retained. Endocavitary electrophysiological recording demonstrated preexcitation of the right ventricle associated with accelerated nodal conduction explaining the narrow QRS complexes in sinus rhythm. The wide complex tachycardias initiated and terminated by paired ventricular stimulation were identical to the spontaneous attacks and were attributed to an antidromic reciprocating rhythm. The hypothesis of a rhythm arising from the accessory pathway is suggested. This would explain the identical configuration of the QRS complexes of the AIVR and of the antidromic reciprocating-rhythm and the disappearance of the AIVR after surgical section of the accessory pathway. PMID:6414416

  6. Autonomic modulation of repolarization instability in patients with heart failure prone to ventricular tachycardia.

    PubMed

    Nayyar, Sachin; Roberts-Thomson, Kurt C; Hasan, Muhammad A; Sullivan, Thomas; Harrington, Judith; Sanders, Prashanthan; Baumert, Mathias

    2013-10-15

    QT variability (QTV) signifies repolarization lability, and increased QTV is a risk predictor for sudden cardiac death. The aim of the present study was to investigate the role of autonomic nervous system activity on QTV. This study was performed in 29 subjects: 10 heart failure (HF) patients with spontaneous ventricular tachycardia [HFVT(+)], 10 HF patients without spontaneous VT [HFVT(-)], and 9 subjects with structurally normal hearts (HNorm). The beat-to-beat QT interval was measured on 3-min records of surface ECGs at baseline and during interventions (atrial pacing and esmolol, isoprenaline, and atropine infusion). Variability in QT intervals was expressed as the SD of all QT intervals (SDQT). The ratio of the SDQT to SD of RR intervals (SDRR) was calculated as an index of QTV normalized to heart rate variability. There was a trend toward a higher baseline SDQT-to-SDRR ratio in the HFVT(+) group compared with the HFVT(-) and HNorm groups (P = 0.09). SDQT increased significantly in the HFVT(+) and HFVT(-) groups compared with the HNorm group during fixed-rate atrial pacing (P = 0.008). Compared with baseline, isoprenaline infusion increased SDQT in HNorm subjects (P = 0.02) but not in HF patients. SDQT remained elevated in the HFVT(+) group relative to the HNorm group despite acute β-adrenoceptor blockade with esmolol (P = 0.02). In conclusion, patients with HF and spontaneous VT have larger fluctuations in beat-to-beat QT intervals. This appears to be a genuine effect that is not solely a consequence of heart rate variation. The effect of acute autonomic nervous system modulation on QTV appears to be limited in HF patients. PMID:23934852

  7. Preprocedural magnetic resonance imaging for image-guided catheter ablation of scar-related ventricular tachycardia.

    PubMed

    Tao, Qian; Piers, Sebastiaan R D; Lamb, Hildo J; Zeppenfeld, Katja; van der Geest, Rob J

    2015-02-01

    To present and validate a highly automated MRI analysis workflow for image-guided catheter ablation of scar-related ventricular tachycardia (VT) ablation procedures. A cohort of 15 post-infarction patients underwent MRI prior to VT ablation. The MRI study included a black-blood turbo spin echo sequence for visualizing the aortic root and ostium of the left main (LM) coronary artery, and a 3D late gadolinium enhanced sequence for visualizing the LV anatomy and myocardial scar substrate. Semi-automated segmentation of the LV, aortic root and ostium of LM was performed, followed by fully automated segmentation of myocardial scar. All segmented structures were aligned using an automated image registration algorithm to remove inter-scan displacement. MRI was integrated at the beginning of the procedure after mapping a single LM point. The integration performance was compared to that of the traditional iterative closest point (ICP) method. The proposed method required a single LM mapping point only, compared to 255 ± 43 points with the ICP method. The single-point method achieved a mean point-to-surface distance of 4.9 ± 1.5 mm on the LV surface and 5.1 ± 1.7 mm on the aorta surface (ICP: 3.7 ± 0.8 and 9.2 ± 7.2 mm, P < 0.05). The Cohen's kappa coefficient between the MRI-defined and EAM-defined scar was 0.36 ± 0.16 for the presented method, significantly higher than that of ICP method (0.23 ± 0.21, P = 0.03), indicating more accurate scar substrate localization during integration. This study demonstrated the feasibility of preprocedural MRI integration into the VT ablation procedure, with highly automated image analysis workflow and minimal mapping effort. PMID:25341408

  8. Eisenmenger syndrome: a case of survival after ventricular tachycardia due to inferior myocardial infarction in a 48-year-old patient with congenital large ventricular septal defect.

    PubMed

    Passarani, Simonetta; Vignati, Gabriele; Einaudi, Arturo

    2004-06-01

    Eisenmenger syndrome is the most common consequence of congenital cyanotic heart disease seen in adults; survival to the fifth decade of life is rare. Death is very difficult to predict: it is related to sudden cardiac ventricular arrhythmia, massive hemoptysis and right heart failure. In this paper, a patient with ventricular septal defect and Eisenmenger reaction is described. The patient was relatively well until 48 years of age, when she underwent surgery because of a cerebral abscess without cerebral complications but with some deterioration of her cardiac function. After discharge, the patient was readmitted to the hospital because the electrocardiogram showed persistent ST inferior elevation. Echocardiography demonstrated poor contractility and inferior akinesia. Sudden ventricular tachycardia occurred and the patient became unconscious. She was successfully resuscitated and, following a period of ventilation, the hemodynamics stabilized and she was discharged 17 days later. She remained well two years later. PMID:15229766

  9. Model of Reentrant Ventricular Tachycardia based upon Infarct Border Zone Geometry Predicts Reentrant Circuit Features as Determined by Activation Mapping

    PubMed Central

    Ciaccio, Edward J; Ashikaga, Hiroshi; Kaba, Riyaz A; Cervantes, Daniel; Hopenfeld, Bruce; Wit, Andrew L; Peters, Nicholas S; McVeigh, Elliot R; Garan, Hasan; Coromilas, James

    2008-01-01

    Background Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. Objective To determine characteristics of post infarction ventricular tachycardia in the IBZ. Methods A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block was expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (ΔT) is maximal, so that the degree of wavefront curvature ρ ∝ ΔT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum ΔT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps following tachycardia induction. Results Mean IBZ thickness was 231±140µm at the reentry isthmus and 1440±770µm in the outer pathway (p<0.001). Mean curvature ρ was 1.63±0.45mm−1 at functional block line locations, 0.71±0.18mm−1 at isthmus entrance-exit points, and 0.33±0.13mm−1 in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32±0.04mm/ms at entrance-exit points, 0.42±0.13mm/ms for the entire outer pathway, and 0.64±0.16mm/ms at outer pathway regions with minimum ΔT. Model sensitivity and specificity to detect isthmus location was 75.0±5.7% and 97.2±0.7%. Conclusions Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships. PMID:17675078

  10. An investigation of the tachycardia produced by intracerebro-ventricular injections of isoprenaline in mice.

    PubMed Central

    Burden, D T; Parkes, M W

    1975-01-01

    1. Isoprenaline, 3.5-20 ng, injected intracerebroventricularly in atropinized mice under pentobarbitone anaesthesia produced a dose-dependent tachycardia. 2. Pretreatment with either reserpine or pempidine blocked nervously-mediated tachycardia as shown by marked reduction of that due to stimulation of the spinal outflow in pithed mice. After pretreatment with these drugs, intracerebroventricular isoprenaline caused tachycardia of a similar degree and time course to that in mice not so pretreated. 3. Pretreatment with either reserpine or pempidine caused supersensitivity to the tachycardia due to intravenous isoprenaline. 4. When allowance was made for this supersensitivity in the effect of intracerebroventricular isoprenaline in pretreated mice, a small dose-dependent residual effect remained that could be attributed to leakage of isoprenaline into the peripheral circulation. 5. This was confirmed by the appearance of a late-developing tachycardia on intracerebroventricular injection of isoprenaline in spinal mice. 6. It is therefore concluded that the tachycardia caused by intracerebroventricular isoprenaline in mice is, at least initially, of central origin. PMID:1137728

  11. Regional myocardial blood flow and coronary vascular reserve in unanesthetized ponies during pacing-induced ventricular tachycardia

    SciTech Connect

    Parks, C.; Manohar, M.; Lundeen, G.

    1983-08-01

    To examine the effects of tachycardia on coronary circulation, transmural distribution of myocardial blood flow (MBF, 15-micron diameter radionuclide-labeled microspheres) was studied in six healthy adult ponies at rest (heart rate . 60 +/- 7 beats . min-1), during ventricular pacing at 150 and 200 beats . min-1, as well as with ventricular pacing at 250 beats . min-1 before and during maximal coronary vasodilatation (iv adenosine infusion; 4 mumole . kg-1 . min-1). Mean aortic pressure and cardiac output were unchanged from control values with ventricular pacing. Whereas ventricular pacing at 150 and 200 beats . min-1 resulted in a progressive uniform increase in transmural MBF and well-maintained endo:epi perfusion ratio, pacing at 250 beats . min-1 did not result in a further increase in MBF compared to pacing at 200 beats . min-1 and the left ventricular (LV) subendocardial:subepicardial (endo:epi) perfusion ratio was significantly less than 1.00 (0.87 +/- 0.05). Blood flow to the LV papillary muscles and subendocardium was significantly less than that recorded at 200 beats . min-1. The LV endo:epi perfusion ratio with ventricular pacing at 250 beats . min-1 during adenosine infusion resulted in a decrease in mean aortic pressure (63% of control value) and a marked further reduction in blood flow to the LV papillary muscles as well as the LV subendocardium, while MBF increased dramatically in the LV subepicardium compared to values observed during ventricular pacing at 250 beats . min-1 alone. These data demonstrate that coronary vasomotion functions to maintain LV subendocardial blood flow in the pony myocardium at a heart rate of 200 beats . min-1, while at 250 beats . min-1 exhaustion of coronary vasodilator reserve in the deeper layers limits further increase in MBF.

  12. Radiofrequency ablation of metastatic chondrosarcoma-associated refractory ventricular tachycardia originating from the right ventricular outflow tract: A case report and literature review

    PubMed Central

    Shi, Xiangmin; Liang, Zhuo; Li, Jian; Guo, Jianping; Shan, Zhaoliang; Wang, Yutang

    2016-01-01

    Ventricular tachycardia (VT) and premature contraction originating from the right ventricular outflow tract (RVOT) usually appear in healthy individuals. Radiofrequency ablation (RFA) is highly effective at resolving this type of arrhythmia. Refractory VT of RVOT is uncommon and occasionally results from cardiac metastasis of extraskeletal mesenchymal chondrosarcomas (ESMC). ESMC is a rare malignant tumor arising from soft tissues. The current study presents the case of a 25-year-old male with severe VT arising from RVOT due to metastasis of an ESMC that originally occurred in the retroperitoneum. The diagnosis was confirmed following echocardiography and cardiac magnetic resonance. VT was eventually eliminated by RFA, and during the 8-month follow-up period the patient did not complain of any palpitations. Holter monitoring confirmed the absence of recurrence. PMID:27588097

  13. 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

  14. Stereotactic Arrhythmia Radioablation (STAR) of Ventricular Tachycardia: A Treatment Planning Study

    PubMed Central

    Fahimian, Benjamin; Soltys, Scott G; Zei, Paul; Lo, Anthony; Gardner, Edward A; Maguire, Patrick J; Loo Jr., Billy W

    2016-01-01

    Purpose The first stereotactic arrhythmia radioablation (STAR) of ventricular tachycardia (VT) was delivered at Stanford on a robotic radiosurgery system (CyberKnife® G4) in 2012. The results warranted further investigation of this treatment. Here we compare dosimetrically three possible treatment delivery platforms for STAR. Methods The anatomy and target volume of the first treated patient were used for this study. A dose of 25 Gy in one fraction was prescribed to the planning target volume (PTV). Treatment plans were created on three treatment platforms: CyberKnife® G4 system with Iris collimator (Multiplan, V. 4.6)(Plan #1), CyberKnife® M6 system with InCise 2TM multileaf collimator (Multiplan V. 5.3)(Plan #2) and Varian TrueBeamTM STx with HD 120TM MLC and 10MV flattening filter free (FFF) beam (Eclipse planning system, V.11) (Plan #3 coplanar and #4 noncoplanar VMAT plans). The four plans were compared by prescription isodose line, plan conformity index, dose gradient, as well as dose to the nearby critical structures. To assess the delivery efficiency, planned monitor units (MU) and estimated treatment time were evaluated. Results Plans #1-4 delivered 25 Gy to the PTV to the 75.0%, 83.0%, 84.3%, and 84.9% isodose lines and with conformity indices of 1.19, 1.16, 1.05, and 1.05, respectively. The dose gradients for plans #1-4 were 3.62, 3.42, 3.93, and 3.73 with the CyberKnife® MLC plan (Plan #2) the best, and the TrueBeamTM STx co-planar plan (Plan #3) the worst. The dose to nearby critical structures (lung, stomach, bowel, and esophagus) were all well within tolerance. The MUs for plans #1-4 were 27671, 16522, 6275, and 6004 for an estimated total-treatment-time/beam-delivery-time of 99/69, 65/35, 37/7, and 56/6 minutes, respectively, under the assumption of 30 minutes pretreatment setup time. For VMAT gated delivery, a 40% duty cycle, 2400MU/minute dose rate, and an extra 10 minutes per extra arc were assumed. Conclusion Clinically acceptable plans were

  15. "Torsade de pointes" tachycardia. Re-entry or focal activity?

    PubMed Central

    D'Alnoncourt, C N; Zierhut, W; Blüderitz, B

    1982-01-01

    Paroxysms of ventricular tachycardia in which the amplitude and the direction of QRS complexes change periodically are defined as "torsade de pointes" tachycardias. The mechanism of this atypical ventricular arrhythmia has not yet been elucidated. The aim of our study was to induce "torsade de pointes" tachycardia experimentally, in order to gain insight into its possible mechanism. The experiments were carried out with isolated porcine hearts, perfused by the Langendorff technique. Epicardial electrocardiograms were recorded by unipolar leads. The specific pattern of "torsade de pointes" tachycardia could be induced by stimulation of the right and left ventricles in phase. From our experimental observations we conclude that a possible cause of "torsade de pointes" tachycardia is the interaction of two ectopic ventricular foci. PMID:7104111

  16. Multiple reentry tachycardia in patients with ventricular preexcitation: report of three cases.

    PubMed

    Murabit, I; Sosa, E; Pileggi, F; Denes, P

    1986-01-01

    The electrophysiologic studies of three patients with accessory pathways and multiple reentrant circuits are reported. The first patient had two atrioventricular accessory pathways: a left posterior capable of bidirectional conduction and a right paraseptal with retrograde conduction only. Four atrioventricular reentry circuits were documented: left and right orthodromic circuits and a left antidromic circuit with retrograde conduction over the right paraseptal accessory pathway. The second patient had a left lateral atrioventricular accessory pathway with type A preexcitation. Two reentrant tachycardias were noted: an atrial tachycardia where the accessory pathway remained concealed and an orthodromic atrioventricular tachycardia. The third patient had dual atrioventricular nodal pathways and a right nodofascicular accessory pathway. The accessory pathway became manifest only when a critical atrioventricular delay was reached, indicating its association with the slow atrioventricular nodal pathway. Wide QRS tachycardia with left bundle branch block contour was documented, by means of the slow atrioventricular nodal pathway and nodofascicular fiber antegradely, and the proximal right bundle branch, the His bundle, and the fast atrioventricular nodal pathway retrogradely. PMID:3946162

  17. Ventricular Tachycardia in the Young Athlete: A Systematic Approach to Selection of Drug Therapy.

    ERIC Educational Resources Information Center

    Podrid, Philip J.

    1986-01-01

    Sustained ventricular tachyarrythmias are uncommon in young people, and underlying heart disease is usually present. This article presents a case study of a 24-year-old male athlete with arrhythmogenic right ventricular dysplasia and points out the value of combinations of drugs versus the use of a single agent. (MT)

  18. High-resolution detection of sustained ventricular and supraventricular tachycardia through FPGA-based fuzzy processing of ECG signal.

    PubMed

    Roy Chowdhury, Shubhajit

    2015-10-01

    The paper presents a field-programmable gate array (FPGA)-based fast processing system with 12-channel high-resolution (24 bits) front-end for ECG signal processing. The implemented high-resolution data conversion makes the system suitable for recording of late potentials of the QRS complex in patients prone to sustained ventricular tachycardia. The system accepts ECG signals through 12 channels and then filtered to minimize baseline wander and power-line interference. The filter outputs are connected to 12 delta-sigma ADCs. The whole ADCs work synchronously at 8 kHz sampling frequency, and their output data are transferred to an FPGA that computes online on the digitized sample values in real time and ascertains whether the patient under study suffers from ventricular tachycardia or not. In order to ascertain the QRS complex accurately in the noisy ECG signal, fuzzy entropy of the sample values has been computed and provided as an input to inverse multiquadratic radial basis function neural network. Using the standard CSE ECG database, the algorithm performed highly effectively. The performance of the algorithm in respect of QRS detection with sensitivity of 99.83 % and accuracy of 99.7 % is achieved when tested using single-channel ECG with entropy criteria. The performance of the QRS detection system has been compared and found to be better than most of the QRS detection systems available in the literature. Using the system, 200 patients have been diagnosed with an accuracy of 99 %. PMID:26251028

  19. Dantrolene rescues arrhythmogenic RYR2 defect in a patient-specific stem cell model of catecholaminergic polymorphic ventricular tachycardia

    PubMed Central

    Jung, Christian B; Moretti, Alessandra; Mederos y Schnitzler, Michael; Iop, Laura; Storch, Ursula; Bellin, Milena; Dorn, Tatjana; Ruppenthal, Sandra; Pfeiffer, Sarah; Goedel, Alexander; Dirschinger, Ralf J; Seyfarth, Melchior; Lam, Jason T; Sinnecker, Daniel; Gudermann, Thomas; Lipp, Peter; Laugwitz, Karl-Ludwig

    2012-01-01

    Coordinated release of calcium (Ca2+) from the sarcoplasmic reticulum (SR) through cardiac ryanodine receptor (RYR2) channels is essential for cardiomyocyte function. In catecholaminergic polymorphic ventricular tachycardia (CPVT), an inherited disease characterized by stress-induced ventricular arrhythmias in young patients with structurally normal hearts, autosomal dominant mutations in RYR2 or recessive mutations in calsequestrin lead to aberrant diastolic Ca2+ release from the SR causing arrhythmogenic delayed after depolarizations (DADs). Here, we report the generation of induced pluripotent stem cells (iPSCs) from a CPVT patient carrying a novel RYR2 S406L mutation. In patient iPSC-derived cardiomyocytes, catecholaminergic stress led to elevated diastolic Ca2+ concentrations, a reduced SR Ca2+ content and an increased susceptibility to DADs and arrhythmia as compared to control myocytes. This was due to increased frequency and duration of elementary Ca2+ release events (Ca2+ sparks). Dantrolene, a drug effective on malignant hyperthermia, restored normal Ca2+ spark properties and rescued the arrhythmogenic phenotype. This suggests defective inter-domain interactions within the RYR2 channel as the pathomechanism of the S406L mutation. Our work provides a new in vitro model to study the pathogenesis of human cardiac arrhythmias and develop novel therapies for CPVT. PMID:22174035

  20. 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

  1. The Different Substrate Characteristics of Arrhythmogenic Triggers in Idiopathic Right Ventricular Outflow Tract Tachycardia and Arrhythmogenic Right Ventricular Dysplasia: New Insight from Noncontact Mapping

    PubMed Central

    Lin, Yenn-Jiang; Higa, Satoshi; Yagi, Nobumori; Chang, Shih-Lin; Lo, Li-Wei; Chung, Fa-Po; Liao, Jo-Nan; Huang, Yen-Chang; Chan, Chao-Shun; Huang, Hung-Kai; Hu, Yu-Feng; Tsao, Hsuan-Ming; Chen, Shih-Ann

    2015-01-01

    Background The aim of this study was to investigate the different substrate characteristics of repetitive premature ventricular complexed (PVC) trigger sites by the non-contact mapping (NCM). Methods Thirty-five consecutive patients, including 14 with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC) and 21 with idiopathic right ventricular outflow tract tachycardia (RVOT VT), were enrolled for electrophysiological study and catheter ablation guided by the NCM. Substrate and electrogram (Eg) characteristics of the earliest activation (EA) and breakout (BO) sites of PVCs were investigated, and these were confirmed by successful PVC elimination. Results Overall 35 dominant focal PVCs were identified. PVCs arose from the focal origins with preferential conduction, breakout, and spread to the whole right ventricle. The conduction time and distance from EA to BO site were both longer in the ARVC than the RVOT group. The conduction velocity was similar between the 2 groups. The negative deflection of local unipolar Eg at the EA site (EA slope3,5,10ms values) was steeper in the RVOT, compared to ARVC patients. The PVCs of ARVC occurred in the diseased substrate in the ARVC patients. More radiofrequency applications were required to eliminate the triggers in ARVC patients. Conclusions/Interpretation The substrate characteristics of PVC trigger may help to differentiate between idiopathic RVOT VT and ARVC. The slowing and slurred QS unipolar electrograms and longer distance from EA to BO in RVOT endocardium suggest that the triggers of ARVC may originate from mid- or sub-epicardial myocardium. More extensive ablation to the trigger site was required in order to create deeper lesions for a successful outcome. PMID:26488594

  2. Dynamic analysis of heart rate may predict subsequent ventricular tachycardia after myocardial infarction

    NASA Technical Reports Server (NTRS)

    Makikallio, T. H.; Seppanen, T.; Airaksinen, K. E.; Koistinen, J.; Tulppo, M. P.; Peng, C. K.; Goldberger, A. L.; Huikuri, H. V.

    1997-01-01

    Dynamics analysis of RR interval behavior and traditional measures of heart rate variability were compared between postinfarction patients with and without vulnerability to ventricular tachyarrhythmias in a case-control study. Short-term fractal correlation of heart rate dynamics was better than traditional measures of heart rate variability in differentiating patients with and without life-threatening arrhythmias.

  3. [Wolff-Parkinson-White syndrome with orthodromic supraventricular tachycardia associated with a "hyper-conductor" atrio-ventricular node. A therapeutic challenge].

    PubMed

    Hernández González, D; Iturralde Torres, P; Romero, L; Colín, L; Villarreal, A; González Hermosillo, J A

    1990-01-01

    One case of Wolff-Parkinson-White Syndrome with paroxysmal supraventricular tachycardia related to orthodromic atrioventricular reentry using an accessory pathway for retrograde conduction an a rapidly conducting AV node for anterograde conduction is present. The pharmacological therapy with Digoxin, Propranolol, Quinidine, Disopyramide and Propafenone was not effective. An electrophysiologic study showed a reciprocating tachycardia induced by spontaneous ventricular beats. Both the effective refractory period of the AV node and the anterograde effective refractory period of the accessory pathway were minor or equal to 220 msec which made the control of the arrhythmia difficult. Amiodarone was able to suppress the premature ventricular beats, depress conduction and prolong refractoriness in both, the AV node and accessory pathway to prevent recurrences of atrioventricular reentry. In this patient a false positive test with ajmaline was documented. The electrophysiologic study showed the association of Wolff-Parkinson-White Syndrome with an enhanced atrioventricular nodal-conduction and allowed the selection of an appropriate antiarrhythmic agent. PMID:2378538

  4. Crescendo in Depolarization and Repolarization Heterogeneity Heralds Development of Ventricular Tachycardia in Hospitalized Patients with Decompensated Heart Failure

    PubMed Central

    Nearing, Bruce D.; Wellenius, Gregory A.; Mittleman, Murray A.; Josephson, Mark E.; Burger, Andrew J.; Verrier, Richard L.

    2012-01-01

    Background A critical need exists for reliable warning markers of in-hospital life-threatening arrhythmias. We employed a new quantitative method to track interlead heterogeneity of depolarization and repolarization to detect premonitory changes prior to ventricular tachycardia (VT) in hospitalized patients with acute decompensated heart failure. Methods and Results Ambulatory ECGs (leads V1, V5, and aVF) recorded before initiation of drug therapy from patients enrolled in the Prospective Randomized Evaluation of Cardiac Ectopy with Dobutamine or Nesiritide Therapy (PRECEDENT) trial were analyzed. R-wave and T-wave heterogeneity (RWH, TWH) were assessed by second central moment analysis and T-wave alternans (TWA) by Modified Moving Average analysis. Patients (N=44) studied included those (N = 22) with episodes of VT (≥4 beats at heart rates >100 beats/min) following ≥120 minutes of stable sinus rhythm and age- and sex-matched patients (N=22) without VT. TWA increased from 18.6±2.1μV (baseline, mean ± SEM) to 27.9±4.6μV in lead V5 at 15–30 minutes prior to VT (p<0.05) and remained elevated until the arrhythmia occurred. TWA results in V1 and aVF were similar. RWH and TWH were elevated from 164.1±33.1μV and 134.5±20.6μV (baseline) to 299.8±54.5μV and 239.2±37.0μV at 30–45 minutes prior to VT (p<0.05), respectively, preceding the crescendo in TWA by 15 minutes. Matched patients without VT did not display elevated RWH (185.5±29.4μV) or TWH (157.1±27.2μV) during the 24–hour period. Conclusions This is the first clinical demonstration of the potential utility of tracking depolarization and repolarization heterogeneity to detect crescendos in electrical instability that could forewarn of impending nonsustained ventricular tachycardia. Clinical Trial Registration http://clinicaltrials.gov; NCT00270400. PMID:22157521

  5. Ventricular Tachycardia from a Central Line Fracture Fragment Embolus: A Rare Complication of a Commonly Used Procedure—A Case Report and Review of the Relevant Literature

    PubMed Central

    Biswas, Saptarshi; McNerney, Patrick

    2015-01-01

    A 22-year-old male admitted with multiple gunshot wounds (GSW) had central line placed initially for hemodynamic monitoring and later for long term antibiotics and total parenteral nutrition (TPN). On postoperative day 4 he presented with bouts of nonsustained ventricular tachycardia; the cause was unknown initially and later attributed to a catheter fragment accidentally severed and lodged in the right heart. Percutaneous retrieval technique was used to successfully extract the catheter fragment and complete recovery was achieved. PMID:26770840

  6. Radiofrequency Ablation of Drug Refractory Ventricular Tachycardia Related to Cocaine Use: A Feasibility, Safety, and Efficacy Study

    PubMed Central

    LAKKIREDDY, DHANUNJAYA; KANMANTHAREDDY, ARUN; BIRIA, MAZDA; REDDY, YERUVA MADHU; PILLARISETTI, JAYASREE; MAHAPATRA, SRIJOY; BERENBOM, LOREN; CHINITZ, LARRY; ATKINS, DONITA; BOMMANA, SUDHARANI; TUNG, RODERICK; BIASE, LUIGI DI; SHIVKUMAR, KALYANAM; NATALE, ANDREA

    2014-01-01

    Background Cocaine use is a known but rare cause of cardiac arrhythmias. Ventricular arrhythmias related to cocaine may not respond to antiarrhythmic drugs and may need treatment with radiofrequency ablation. Objectives We describe the clinical and electrophysiological characteristics of cocaine-related ventricular tachycardia (VT) from a multicenter registry. Methods Subjects presenting with VT related to cocaine use and being considered for radiofrequency ablation have been included in the study. Patients who were refractory to maximal medical therapy underwent radiofrequency ablation of the VT. Clinical, procedural variables, efficacy, and safety outcomes were assessed. Results A total of 14 subjects met study criteria (age 44 ± 13, range 18-to 68-year-old with 79% male, 71% Caucasian). MRI showed evidence of scar only in 43% of patients (6/14). The mechanism of VT was focal in 50% (n = 7) and scar related reentry in 50% (n = 7) based on 3D mapping. The mean VT cycle length was 429 ± 96 milliseconds. The site of origin was epicardial in 16% (3/18) of VTs. Most clinical VTs were hemodynamically stable (75%). Mean ejection fraction at the time of admission was 44 ± 14%. Duration of procedure was 289 ± 50 minutes. One subject developed pericardial tamponade requiring drainage. At 18 ± 11 months follow-up, freedom from arrhythmia was seen in 86% (1 case lost to follow-up and 2 died). Conclusion Radiofrequency ablation is not only feasible but also safe and effective in patients who have drug refractory VT related to chronic cocaine use. PMID:24724798

  7. Effects of Fibrosis Morphology on Reentrant Ventricular Tachycardia Inducibility and Simulation Fidelity in Patient-Derived Models

    PubMed Central

    Ringenberg, Jordan; Deo, Makarand; Filgueiras-Rama, David; Pizarro, Gonzalo; Ibañez, Borja; Peinado, Rafael; Merino, José L; Berenfeld, Omer; Devabhaktuni, Vijay

    2014-01-01

    Myocardial fibrosis detected via delayed-enhanced magnetic resonance imaging (MRI) has been shown to be a strong indicator for ventricular tachycardia (VT) inducibility. However, little is known regarding how inducibility is affected by the details of the fibrosis extent, morphology, and border zone configuration. The objective of this article is to systematically study the arrhythmogenic effects of fibrosis geometry and extent, specifically on VT inducibility and maintenance. We present a set of methods for constructing patient-specific computational models of human ventricles using in vivo MRI data for patients suffering from hypertension, hypercholesterolemia, and chronic myocardial infarction. Additional synthesized models with morphologically varied extents of fibrosis and gray zone (GZ) distribution were derived to study the alterations in the arrhythmia induction and reentry patterns. Detailed electrophysiological simulations demonstrated that (1) VT morphology was highly dependent on the extent of fibrosis, which acts as a structural substrate, (2) reentry tended to be anchored to the fibrosis edges and showed transmural conduction of activations through narrow channels formed within fibrosis, and (3) increasing the extent of GZ within fibrosis tended to destabilize the structural reentry sites and aggravate the VT as compared to fibrotic regions of the same size and shape but with lower or no GZ. The approach and findings represent a significant step toward patient-specific cardiac modeling as a reliable tool for VT prediction and management of the patient. Sensitivities to approximation nuances in the modeling of structural pathology by image-based reconstruction techniques are also implicated. PMID:25368538

  8. A Historical Perspective on the Role of Functional Lines of Block in the Re-entrant Circuit of Ventricular Tachycardia.

    PubMed

    Proietti, Riccardo; Roux, Jean-Francois; Verma, Atul; Alturki, Ahmed; Bernier, Martin L; Essebag, Vidal

    2016-05-01

    The ablation strategy for ventricular tachycardia (VT) rapidly evolved from an entrainment mapping approach for identification of the critical isthmus of the re-entrant circuit during monomorphic VT, toward a substrate-based approach aiming to ablate surrogate markers of the circuit during sinus rhythm in hemodynamically nontolerated and polymorphic VT. The latter approach implies an assumption that the circuits responsible for the arrhythmia are anatomical or fixed, and present during sinus rhythm. Accordingly, the lines of block delimiting the channels of the circuits are often considered fixed, although there is evidence that they are functional or more frequently a combination of fixed and functional. The electroanatomical substrate-based approach to VT ablation performed during sinus rhythm is increasingly adopted in clinical practice and often described as scar homogenization, scar dechanneling, or core isolation. However, whether the surrogate markers of the VT circuit during sinus rhythm match the circuit during arrhythmias remains to be fully demonstrated. The myocardial scar is a heterogeneous electrophysiological milieu with complex arrhythmogenic mechanisms that potentially coexist simultaneously. Moreover, the scar consists of different areas of diverse refractoriness and conduction. It can be misleading to limit the arrhythmogenic perspective of the myocardial scar to fixed or anatomical barriers held responsible for the re-entry circuit. Greater understanding of the role of functional lines of block in VT and the validity of the surrogate targets being ablated is necessary to further improve the technique and outcome of VT ablation. PMID:26852719

  9. False ventricular tachycardia alarm suppression in the ICU based on the discrete wavelet transform in the ECG signal.

    PubMed

    Salas-Boni, Rebeca; Bai, Yong; Harris, Patricia Rae Eileen; Drew, Barbara J; Hu, Xiao

    2014-01-01

    Over the past few years, reducing the number of false positive cardiac monitor alarms (FA) in the intensive care unit (ICU) has become an issue of the utmost importance. In our work, we developed a robust methodology that, without the need for additional non-ECG waveforms, suppresses false positive ventricular tachycardia (VT) alarms without resulting in false negative alarms. Our approach is based on features extracted from the ECG signal 20 seconds prior to a triggered alarm. We applied a multi resolution wavelet transform to the ECG data 20seconds prior to the alarm trigger, extracted features from appropriately chosen scales and combined them across all available leads. These representations are presented to a L1-regularized logistic regression classifier. Results are shown in two datasets of physiological waveforms with manually assessed cardiac monitor alarms: the MIMIC II dataset, where we achieved a false alarm (FA) suppression of 21% with zero true alarm (TA) suppression; and a dataset compiled by UCSF and General Electric, where a 36% FA suppression was achieved with a zero TA suppression. The methodology described in this work could be implemented to reduce the number of false monitor alarms in other arrhythmias. PMID:25172188

  10. Catheter ablation of ventricular tachycardia: Lessons learned from past clinical trials and implications for future clinical trials.

    PubMed

    Pokorney, Sean D; Friedman, Daniel J; Calkins, Hugh; Callans, David J; Daoud, Emile G; Della-Bella, Paolo; Jackson, Kevin P; Shivkumar, Kalyanam; Saba, Samir; Sapp, John; Stevenson, William G; Al-Khatib, Sana M

    2016-08-01

    Catheter ablation of ventricular tachycardia (VT) has evolved in recent years, especially in patients with ischemic heart disease. Data from prospective studies show that VT catheter ablation reduces the risk of recurrent VT; however, there is a paucity of data on the effect of VT catheter ablation on mortality and patient-centered outcomes such as quality of life. Performing randomized clinical trials of VT catheter ablation can be fraught with challenges, and, as a result, several prior trials of VT catheter ablation had to be stopped prematurely. The main challenges are inability to blind the patient to therapy to obtain a traditional control group, high crossover rates between the 2 arms of the study, patient refusal to participate in trials in which they have an equal chance of receiving a "pill" vs an invasive procedure, heterogeneity of mapping and ablation techniques as well as catheters and equipment, rapid evolution of technology that may make findings of any long trial less relevant to clinical practice, lack of consensus on what constitutes acute procedural and long-term success, and presentation of patients to electrophysiologists late in the course of their disease. In this article, a panel of experts on VT catheter ablation and/or clinical trials of VT catheter ablation review challenges faced in conducting prior trials of VT catheter ablation and offer potential solutions for those challenges. It is hoped that the proposed solutions will enhance the feasibility of randomized clinical trials of VT catheter ablation. PMID:27050910

  11. 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

  12. Anatomical Substrates and Ablation of Reentrant Atrial and Ventricular Tachycardias in Repaired Congenital Heart Disease.

    PubMed

    Brouwer, Charlotte; Hazekamp, Mark G; Zeppenfeld, Katja

    2016-08-01

    Advances in surgical repair techniques for various types of congenital heart disease have improved survival into adulthood over the past decades, thus exposing these patients to a high risk of atrial and ventricular arrhythmias later in life. These arrhythmias arise from complex arrhythmogenic substrates. Substrate formation may depend on both pathological myocardial remodelling and variable anatomical boundaries, determined by the type and timing of prior corrective surgery. Accordingly, arrhythmogenic substrates after repair have changed as a result of evolving surgical techniques. Radiofrequency catheter ablation offers an important therapeutic option but remains challenging due to the variable anatomy, surgically created obstacles and the complex arrhythmogenic substrates. Recent technical developments including electroanatomical mapping and image integration for delineating the anatomy facilitate complex catheter ablation procedures. The purpose of this review is to provide an update on the changing anatomical arrhythmogenic substrates and their potential impact on catheter ablation in patients with repaired congenital heart disease and tachyarrhythmias. PMID:27617095

  13. Anatomical Substrates and Ablation of Reentrant Atrial and Ventricular Tachycardias in Repaired Congenital Heart Disease

    PubMed Central

    Brouwer, Charlotte; Hazekamp, Mark G

    2016-01-01

    Advances in surgical repair techniques for various types of congenital heart disease have improved survival into adulthood over the past decades, thus exposing these patients to a high risk of atrial and ventricular arrhythmias later in life. These arrhythmias arise from complex arrhythmogenic substrates. Substrate formation may depend on both pathological myocardial remodelling and variable anatomical boundaries, determined by the type and timing of prior corrective surgery. Accordingly, arrhythmogenic substrates after repair have changed as a result of evolving surgical techniques. Radiofrequency catheter ablation offers an important therapeutic option but remains challenging due to the variable anatomy, surgically created obstacles and the complex arrhythmogenic substrates. Recent technical developments including electroanatomical mapping and image integration for delineating the anatomy facilitate complex catheter ablation procedures. The purpose of this review is to provide an update on the changing anatomical arrhythmogenic substrates and their potential impact on catheter ablation in patients with repaired congenital heart disease and tachyarrhythmias.

  14. Transition from ventricular fibrillation to ventricular tachycardia: a simulation study on the role of Ca(2+)-channel blockers in human ventricular tissue.

    PubMed

    Bernus, O; Van Eyck, B; Verschelde, H; Panfilov, A V

    2002-12-01

    We study the effect of blocking the L-type Ca(2+)-channel on fibrillation in simulations in two-dimensional (2D) isotropic sheets of ventricular tissue and in a three-dimensional anisotropic anatomical model of human ventricles, using a previously developed model of human ventricular cells. Ventricular fibrillation (VF) was obtained as a result of spiral wave breakup and consisted of a varying number of chaotically wandering wavelets activating tissue at a frequency of about 6.0 Hz. We show that blocking the Ca(2+)-current by 75% can convert ventricular fibrillation into a periodic regime with a small number of stable spiral waves, ranging from six in 2D sheets of 25 x 25 cm to a single spiral in the anatomical model of human ventricles. The dominant frequency during this process changed to about 10.0 Hz in the 2D simulations, but to only 5.0 Hz in the whole heart simulations where a single spiral wave anchored around an anatomical obstacle. We show that the observed effects were due to a flattening of the electrical restitution curve, which prevented the generation of wave breaks and stabilized the activation patterns. PMID:12502041

  15. Association of Late Gadolinium Enhancement and Degree of Left Ventricular Hypertrophy Assessed on Cardiac Magnetic Resonance Imaging With Ventricular Tachycardia in Children With Hypertrophic Cardiomyopathy.

    PubMed

    Spinner, Joseph A; Noel, Cory V; Denfield, Susan W; Krishnamurthy, Rajesh; Jeewa, Aamir; Dreyer, William J; Maskatia, Shiraz A

    2016-04-15

    There are limited data on the clinical significance of left ventricular (LV) mass and late gadolinium enhancement (LGE) in pediatric hypertrophic cardiomyopathy (HC). We reviewed cardiovascular magnetic resonance (CMR) studies of children with HC to investigate the associations between the extent and distribution of LGE and LV mass with ventricular tachycardia (VT) in children with HC. A blinded observer reviewed CMR studies for the presence and distribution of LV hypertrophy and LGE using a 17-segment model. The primary outcome was VT. LGE was present 17 of 33 subjects (52%). VT was present on outpatient Holter monitor or exercise stress test in 7 patients, of which 5 patients (71%) had LGE. Each additional segment of LGE was associated with an increase in the odds of VT (odds ratio [OR] 1.4, 95% CI 1.1 to 1.9) and fewer than 5 segments with LGE had 93% specificity for the presence or absence of VT (OR 0.06, 95% CI 0.01 to 0.5). VT was more common in patients with LGE in the apical septal (p = 0.03), basal inferoseptal (p <0.01), and basal inferior (p = 0.04) segments, whereas LGE in more commonly involved segments (midanteroseptal and midinferoseptal) was not associated with VT (p = 0.13, 0.26). Patients with VT had greater LV mass index (76.4 ± 40.4 g/m(2.7) vs 50.9 ± 24.3 g/m(2.7); p = 0.03). Each centimeter of increased maximum LV thickness was associated with increased likelihood of VT (OR 2.9, 95% CI 1.2 to 6.8). In conclusion, in pediatric HC, CMR to evaluate the extent and pattern of LGE, LV mass index, and maximum LV thickness may help to identify children with HC at risk of VT. PMID:26892450

  16. Model of unidirectional block formation leading to reentrant ventricular tachycardia in the infarct border zone of postinfarction canine hearts

    PubMed Central

    Ciaccio, Edward J.; Coromilas, James; Ashikaga, Hiroshi; Cervantes, Daniel O.; Wit, Andrew L.; Peters, Nicholas S.; McVeigh, Elliot R.; Garan, Hasan

    2015-01-01

    Background When the infarct border zone is stimulated prematurely, a unidirectional block line (UBL) can form and lead to double-loop (figure-of-eight) reentrant ventricular tachycardia (VT) with a central isthmus. The isthmus is composed of an entrance, center, and exit. It was hypothesized that for certain stimulus site locations and coupling intervals, the UBL would coincide with the isthmus entrance boundary, where infarct border zone thickness changes from thin-to-thick in the travel direction of the premature stimulus wavefront. Method A quantitative model was developed to describe how thin-to-thick changes in the border zone result in critically convex wavefront curvature leading to conduction block, which is dependent upon coupling interval. The model was tested in 12 retrospectively analyzed postinfarction canine experiments. Electrical activation was mapped for premature stimulation and for the first reentrant VT cycle. The relationship of functional conduction block forming during premature stimulation to functional block during reentrant VT was quantified. Results For an appropriately placed stimulus, in accord with model predictions: (1) The UBL and reentrant VT isthmus lateral boundaries overlapped (error: 4.8±5.7 mm). (2) The UBL leading edge coincided with the distal isthmus where the center-entrance boundary would be expected to occur. (3) The mean coupling interval was 164.6±11.0 ms during premature stimulation and 190.7±20.4 ms during the first reentrant VT cycle, in accord with model calculations, which resulted in critically convex wavefront curvature with functional conduction block, respectively, at the location of the isthmus entrance boundary and at the lateral isthmus edges. Discussion Reentrant VT onset following premature stimulation can be explained by the presence of critically convex wavefront curvature and unidirectional block at the isthmus entrance boundary when the premature stimulation interval is sufficiently short. The

  17. Discrepant effects of mexiletine on cycle length of ventricular tachycardia and on the effective refractory period in the area of slow conduction.

    PubMed Central

    Aizawa, Y.; Chinushi, M.; Kitazawa, H.; Washizuka, T.; Abe, A.; Shibata, A.; Kodama, I.

    1996-01-01

    OBJECTIVE: Monomorphic sustained ventricular tachycardia (VT) can often be entrained and interrupted at a critical paced cycle length. The aim was to evaluate a possible determinant of this phenomenon by observing the action of mexiletine on the critical paced cycle length and other variables. METHODS: Nine consecutive patients with symptomatic VT were studied. After induction of VT, the area of slow conduction was mapped as the earliest site of the activation or the site with mid-diastolic potential during the tachycardia. Rapid pacing was performed at a site distant from the tachycardia circuit to entrain the tachycardia, starting at a cycle length 10-20 ms shorter than the VT cycle length, and repeated after a decrement of the cycle length in steps of 10 ms to obtain the longest paced cycle length that interrupted the tachycardia: the block cycle length. The effective refractory period (ERP) was measured at the pacing site at which the myocardium was presumed to be normal and also in the area of slow conduction. The effects of mexiletine on the cycle length of VT, the block cycle length, and the ERP at two sites were obtained before and after mexiletine administration. The relation between the cycle length of VT and block cycle length and their changes were also analysed. RESULTS: 11 VTs with the same morphology were induced before and after mexiletine administration. The VT cycle length was prolonged by mexiletine from 309 (SD 53) to 361 (47) ms, and it was interrupted at block cycle lengths of 247 (37) and 307 (41) ms, respectively, the changes being 18 (12)% and 23 (8)% (both P < 0.001). All VTs were entrained, and during pacing at the block cycle length there was abrupt loss of fusion and change in the presystolic electrogram, always associated with interruption of VT on cessation of rapid pacing. A good correlation was observed between the VT cycle length and the block cycle length (r = 0.77 to 0.80). The ERP at the pacing site (normal myocardium) and in

  18. Prognostic value of non-sustained ventricular tachycardia and the potential role of amiodarone treatment in hypertrophic cardiomyopathy: assessment in an unselected non-referral based patient population

    PubMed Central

    Cecchi, F; Olivotto, I; Montereggi, A; Squillatini, G; Dolara, A; Maron, B

    1998-01-01

    Background—Amiodarone has been reported to reduce the likelihood of sudden death in patients with hypertrophic cardiomyopathy (HCM). However, data regarding the clinical course in HCM have traditionally come from selected referral populations biased toward assessment of high risk patients.
Aims—To evaluate antiarrhythmic treatment for sudden death in an HCM population not subject to tertiary referral bias, closely resembling the true disease state present in the community.
Methods—Cardiovascular mortality was assessed in relation to the occurrence of non-sustained ventricular tachycardia (NSVT) on 24 or 48 hour ambulatory Holter recording, a finding previously regarded as a marker for sudden death, particularly when the arrhythmia was frequent, repetitive or prolonged. 167 consecutive patients were analysed by multiple Holter ECG recordings (mean (SD) 157 (129) hours) and followed for a mean of 10 (5) years. Only patients with multiple repetitive NSVT were treated with amiodarone, and in relatively low doses (220 (44) mg/day).
Results—Nine HCM related deaths occurred: 8 were the consequence of congestive heart failure, but only 1 was sudden and unexpected. Three groups of patients were segregated based on their NSVT profile: group 1 (n = 39), multiple (⩾ 2 runs) and repetitive bursts (on ⩾ 2 Holters) of NSVT, or prolonged runs of ventricular tachycardia, included 4 deaths due to heart failure; group 2 (n = 38), isolated infrequent bursts of NSVT, included 1 sudden death; group 3 (n = 90), without NSVT, included 4 heart failure deaths. Kaplan-Meier survival analysis showed no significant differences in survival between the three groups throughout follow up.
Conclusions—In an unselected patient population with HCM, isolated, non-repetitive bursts of NSVT were not associated with adverse prognosis and so this arrhythmia does not appear to justify chronic antiarrhythmic treatment. Amiodarone, administered in relatively low

  19. Phase statistics approach to human ventricular fibrillation

    NASA Astrophysics Data System (ADS)

    Wu, Ming-Chya; Watanabe, Eiichi; Struzik, Zbigniew R.; Hu, Chin-Kun; Yamamoto, Yoshiharu

    2009-11-01

    Ventricular fibrillation (VF) is known to be the most dangerous cardiac arrhythmia, frequently leading to sudden cardiac death (SCD). During VF, cardiac output drops to nil and, unless the fibrillation is promptly halted, death usually ensues within minutes. While delivering life saving electrical shocks is a method of preventing SCD, it has been recognized that some, though not many, VF episodes are self-terminating, and understanding the mechanism of spontaneous defibrillation might provide newer therapeutic options for treatment of this otherwise fatal arrhythmia. Using the phase statistics approach, recently developed to study financial and physiological time series, here, we reveal the timing characteristics of transient features of ventricular tachyarrhythmia (mostly VF) electrocardiogram (ECG) and find that there are three distinct types of probability density function (PDF) of phase distributions: uniform (UF), concave (CC), and convex (CV). Our data show that VF patients with UF or CC types of PDF have approximately the same probability of survival and nonsurvival, while VF patients with CV type PDF have zero probability of survival, implying that their VF episodes are never self-terminating. Our results suggest that detailed phase statistics of human ECG data may be a key to understanding the mechanism of spontaneous defibrillation of fatal VF.

  20. Application of neural classifier to risk recognition of sustained ventricular tachycardia and flicker in patients after myocardial infarction based on high-resolution electrocardiography

    NASA Astrophysics Data System (ADS)

    Wydrzyński, Jacek; Jankowski, Stanisław; Piątkowska-Janko, Ewa

    2008-01-01

    This paper presents the application of neural networks to the risk recognition of sustained ventricular tachycardia and flicker in patients after myocardial infarction based on high-resolution electrocardiography. This work is based on dataset obtained from the Medical University of Warsaw. The studies were performed on one multiclass classifier and on binary classifiers. For each case the optimal number of hidden neurons was found. The effect of data preparation: normalization and the proper selection of parameters was considered, as well as the influence of applied filters. The best neural classifier contains 5 hidden neurons, the input ECG signal is represented by 8 parameters. The neural network classifier had high rate of successful recognitions up to 90% performed on the test data set.

  1. Differential diagnosis of wide QRS tachycardias.

    PubMed

    Lobban, J H; Schmidt, S B; Rhodes, L A; Jain, A C

    1994-06-01

    This article has reviewed the differential diagnosis of wide QRS tachycardia. We have found the stepwise approach suggested by Brugada to be very useful. Of the newer criteria that he proposes, the R to S interval of > 100 ms. appears to be a particularly helpful clue favoring the diagnosis of ventricular tachycardia. Hemodynamic stability, young age, 1:1 AV association, and the absence of structural heart disease do not exclude a diagnosis of ventricular tachycardia. Most wide QRS tachycardias in adults are ventricular, and when all else fails, one will be right more often than not in favoring this as the diagnosis over supraventricular tachycardia with aberrancy. The R to S interval is measured in the precordial (V) leads from the onset of the R wave to the deepest part of the S wave. A value > 100 ms. in any V lead strongly favors ventricular tachycardia. Example is from Case 1 (upper tracing is V1). PMID:8067039

  2. Surgery for postinfarction ventricular tachycardia in the pre-implantable cardioverter defibrillator era: early and long term outcomes in 100 consecutive patients

    PubMed Central

    Bourke, J; Campbell, R; McComb, J; Furniss, S; Doig, J; Hilton, C

    1999-01-01

    OBJECTIVE—To report outcome following surgery for postinfarction ventricular tachycardia undertaken in patients before the use of implantable defibrillators.
DESIGN—A retrospective review, with uniform patient selection criteria and surgical and mapping strategy throughout. Complete follow up. Long term death notification by OPCS (Office of Population Censuses and Statistics) registration.
SETTING—Tertiary referral centre for arrhythmia management.
PATIENTS—100 consecutive postinfarction patients who underwent map guided endocardial resection at this hospital in the period 1981-91 for drug refractory ventricular tachyarrhythmias.
RESULTS—Emergency surgery was required for intractable arrhythmias in 28 patients, and 32 had surgery within eight weeks of infarction ("early"). Surgery comprised endocardial resections in all, aneurysmectomy in 57, cryoablations in 26, and antiarrhythmic ventriculotomies in 11. Twenty five patients died < 30 days after surgery, 21 of cardiac failure. This high mortality reflects the type of patients included in the series. Only 12 received antiarrhythmic drugs after surgery. Perioperative mortality was related to preoperative left ventricular function and the context of surgery. Mortality rates for elective surgery more than eight weeks after infarction, early surgery, emergency surgery, and early emergency surgery were 18%, 31%, 46%, and 50%, respectively. Actuarial survival rates at one, three, five, and 10 years after surgery were 66%, 62%, 57%, and 35%.
CONCLUSIONS—Surgery offers arrhythmia abolition at a risk proportional to the patient's preoperative risk of death from ventricular arrhythmias. The long term follow up results suggest a continuing role for surgery in selected patients even in the era of catheter ablation and implantable defibrillators.


Keywords: arrhythmias; myocardial infarction; surgical management PMID:10409528

  3. Chronic cough and tachycardia-induced cardiomyopathy in a patient with idiopathic frequent, monomorphic premature ventricular contractions.

    PubMed

    Hasdemir, Can; Musayev, Oktay; Kehribar, Demet Yalcin; Kartal, Yildirim; Can, Levent H

    2013-05-01

    A 70-year-old woman presented with a 1-year history of dry cough. Extensive work-up ruled out common causes of chronic cough. She was found to have very frequent, monomorphic premature ventricular contractions (PVCs) and mild-to-moderate left ventricular systolic dysfunction. Propafenone 450 mg/day resulted in complete resolution of her cough and disappearance of PVCs within 24 hours of initiation. One month after the initiation of propafenone therapy, left ventricular ejection fraction normalized and her chronic cough resolved completely. PMID:21967685

  4. Menstrual cycle phase does not affect sympathetic neural activity in women with postural orthostatic tachycardia syndrome

    PubMed Central

    Stickford, Abigail SL; VanGundy, Tiffany B; Levine, Benjamin D; Fu, Qi

    2015-01-01

    Abstract Patients with the postural orthostatic tachycardia syndrome (POTS) are primarily premenopausal women, which may be attributed to female sex hormones. We tested the hypothesis that hormonal fluctuations of the menstrual cycle alter sympathetic neural activity and orthostatic tolerance in POTS women. Ten POTS women were studied during the early follicular (EF) and mid-luteal (ML) phases of the menstrual cycle. Haemodynamics and muscle sympathetic nerve activity (MSNA) were measured when supine, during 60 deg upright tilt for 45 min or until presyncope, and during the cold pressor test (CPT) and Valsalva manoeuvres. Blood pressure and total peripheral resistance were higher during rest and tilting in the ML than EF phase; however, heart rate, stroke volume and cardiac output were similar between phases. There were no mean ± SD differences in MSNA burst frequency (8 ± 8 EF phase vs. 10 ± 10 bursts min–1 ML phase at rest; 34 ± 15 EF phase vs. 36 ± 16 bursts min–1 ML phase at 5 min tilt), burst incidence or total activity, nor any differences in the cardiovagal and sympathetic baroreflex sensitivities between phases under any condition. The incidence of presyncope was also the same between phases. There were no differences in haemodynamic or sympathetic responses to CPT or Valsalva. These results suggest that the menstrual cycle does not affect sympathetic neural activity but modulates blood pressure and vasoconstriction in POTS women during tilting. Thus, factors other than sympathetic neural activity are probably responsible for the symptoms of orthostatic intolerance across the menstrual cycle in women with POTS. Key points Women with the postural orthostatic tachycardia syndrome (POTS) report fluctuations in orthostatic tolerance throughout the menstrual cycle. The mechanism(s) underlying blood pressure control across the menstrual cycle in women with POTS are unknown. The findings of the present study indicate that the menstrual

  5. [Vector cardiographic evaluation of monomorphic ventricular tachycardia; its relation to the type of cardiopathy, vagal tonus and the prevalence of late potentials].

    PubMed

    Rosas Peralta, M; Casanova Garcés, J M; González Hermosillo, J A

    1994-01-01

    The most common cause of sudden death is malignant ventricular arrhytHmia. In order to identify the predictive value of the vectospatial evaluation in the surface electrocardiogram during a monomorphic ventricular tachycardia (MVT), and the equilibrium state of AutonomOus Nervous System (ANS), 89 patients of both sexes were studied with mean age of 47 +/- 16.2 years. They were grouped as follows: Group I included 43 patients (P), with a coronary heart disease; Group II (n = 24P) with a noncoronary myocardiopathy and Group III (n = 22P) with unknown origin MVT (Cryptogenic). Relationship between QRS configuration in the frontal plane (QRSf) during MVT episode with transverse plane, cardiac position in the chest X-rays, presence and duration of late potentials (LPs) in their two types of analysis (time domain and spectral mapping by high-resolution electrocardiogram), heart rate variability and ejection fraction by echocardiography were determined in all patients. The QRSf configuration with left bundle-branch block (LBBB) was the most common in group I, the sustained MVT (SMVT) + LBBB was associated with both prevalence and duration of late potentials (p = 0.005), low-rate heart variability and ejection fraction < 40%. SMVT + LBBB was the most common type in group III and if it has shown and inferior axis, an elevated rate of LPs (+) was seen. Situation that oriented to an arrhythmogenic right ventricular dysplasia. Low amplitude signals with short duration in the time domain were seen in group I with LBBB; and with SMVT + RBBB in group II. We suggest that vectospatial evaluation of QRSf during a MVT is a greater importance in the risk stratification for sudden death and it can guide to anatomic origin and the diagnosis-therapeutic approach. PMID:8179433

  6. 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

  7. Pro-arrhythmogenic effects of CACNA1C G1911R mutation in human ventricular tachycardia: insights from cardiac multi-scale models.

    PubMed

    Bai, Jieyun; Wang, Kuanquan; Li, Qince; Yuan, Yongfeng; Zhang, Henggui

    2016-01-01

    Mutations in the CACNA1C gene are associated with ventricular tachycardia (VT). Although the CACNA1C mutations were well identified in patients with cardiac arrhythmias, mechanisms by which cardiac arrhythmias are generated in such genetic mutation conditions remain unclear. In this study, we identified a novel mechanism of VT resulted from enhanced repolarization dispersion which is a key factor for arrhythmias in the CACNA1C G1911R mutation using multi-scale computational models of the human ventricle. The increased calcium influx in the mutation prolonged action potential duration (APD), produced steepened action potential duration restitution (APDR) curves as well as augmented membrane potential differences among different cell types during repolarization, increasing transmural dispersion of repolarization (DOR) and the spatial and temporal heterogeneity of cardiac electrical activities. Consequentially, the vulnerability to unidirectional conduction block in response to a premature stimulus increased at tissue level in the G1911R mutation. The increased functional repolarization dispersion anchored reentrant excitation waves in tissue and organ models, facilitating the initiation and maintenance of VT due to less meandering rotor tip. Thus, the increased repolarization dispersion caused by the G1911R mutation is a primary factor that may primarily contribute to the genesis of cardiac arrhythmias in Timothy Syndrome. PMID:27502440

  8. [Comparative study of T-wave alternans, QT c dispersion and late potential for predicting ventricular tachycardia in patients with ischemic heart disease].

    PubMed

    Ohisa, Noriko; Ohira, Mika; Mizonobe, Katsumi; Funato, Tadao; Kaku, Mitsuo; Munakata, Yasuhiko

    2002-02-01

    Ventricular tachycardia(VT) is well known as the life-threatening arrhythmia. It would be important for predicting the risk of VT to prevent sudden death caused by VT after myocardial damage such as old myocardial infarction and dilated cardiomyopathy. In this study, we examined late potential(LP), TWA alternans(TWA), and QTc dispersion(QTcd) measured by Holter ECG, in 21 patients with old myocardial infarction(OMI) and 21 patients with dilated cardiomyopathy(DCM), and evaluated these parameters in relation with the occurrence of VT on these patients. The sensitivities of LP, TWA, and QTcd in patients with OMI in relation with VT were 82%, 73%, and 82%, respectively, and those in patients with DCM were 82%, 93%, and 73%, respectively. The specificities of LP, TWA, and QTcd in patients with OMI in relation with VT were 100%, 40%, and 100%, respectively, and those in patients with DCM were 100%, 30%, and 100%, respectively. The data demonstrated that LP and TWA were the useful predictive parameters for the VT on myocardial damage such as OMI and DCM. PMID:11925858

  9. A Novel Methodology for Assessing the Bounded-Input Bounded-Output Instability in QT Interval Dynamics: Application to Clinical ECG With Ventricular Tachycardia

    PubMed Central

    Chen, Xiaozhong; Trayanova, Natalia A.

    2012-01-01

    The goal of this paper is to present a new methodology for assessing the bounded-input bounded-output (BIBO) stability in QT interval (QTI) dynamics from clinical ECG. The ECG recordings were collected from 15 patients who experienced ventricular tachycardia (VT). Ten-minute-long ECG recordings extracted immediately before the onset of a chosen VT, one per patient, were assembled into a VT group, while the control group comprised 10-min-long ECGs extracted 1 h before VT onset and at least 1 h after any prior arrhythmic event. Each 10-min recording was subdivided into 1-min ECG recordings (minECGs). The QTI dynamics of each minECG was defined as a function of several prior QTIs and RR intervals; the BIBO stability of this function was then assessed in the z-domain. The number of minECGs with unstable QTI dynamics (Nus) and the frequency of premature activations (PA), fPA, were counted for each ECG recording and were compared between the VT and control groups. The results show that the present methodology successfully captured the instability in QTI dynamics leading to VT onset in the studied population. Significantly larger Nus was found in the VT group compared against the control and a positive correlation between Nus and fPA was identified in both groups. PMID:21984490

  10. Pro-arrhythmogenic effects of CACNA1C G1911R mutation in human ventricular tachycardia: insights from cardiac multi-scale models

    PubMed Central

    Bai, Jieyun; Wang, Kuanquan; Li, Qince; Yuan, Yongfeng; Zhang, Henggui

    2016-01-01

    Mutations in the CACNA1C gene are associated with ventricular tachycardia (VT). Although the CACNA1C mutations were well identified in patients with cardiac arrhythmias, mechanisms by which cardiac arrhythmias are generated in such genetic mutation conditions remain unclear. In this study, we identified a novel mechanism of VT resulted from enhanced repolarization dispersion which is a key factor for arrhythmias in the CACNA1C G1911R mutation using multi-scale computational models of the human ventricle. The increased calcium influx in the mutation prolonged action potential duration (APD), produced steepened action potential duration restitution (APDR) curves as well as augmented membrane potential differences among different cell types during repolarization, increasing transmural dispersion of repolarization (DOR) and the spatial and temporal heterogeneity of cardiac electrical activities. Consequentially, the vulnerability to unidirectional conduction block in response to a premature stimulus increased at tissue level in the G1911R mutation. The increased functional repolarization dispersion anchored reentrant excitation waves in tissue and organ models, facilitating the initiation and maintenance of VT due to less meandering rotor tip. Thus, the increased repolarization dispersion caused by the G1911R mutation is a primary factor that may primarily contribute to the genesis of cardiac arrhythmias in Timothy Syndrome. PMID:27502440

  11. Magnetocardiographic intra-QRS fragmentation analysis in the identification of patients with sustained ventricular tachycardia after myocardial infarction.

    PubMed

    Korhonen, P; Montonen, J; Endt, P; Mäkijärvi, M; Trahms, L; Katila, T; Toivonen, L

    2001-08-01

    The aim of this study was to investigate if magnetocardiographic (MCG) analysis of cardiac micropotentials within the QRS complex can identity patients prone to ventricular arrhythmias, and to compare it to MCG time-domain, late-field analysis. The study population consisted of 136 patients with remote MI, 53 with and 83 without a history of VT. After averaging and high pass filtering of multichannel MCG signals, time-domain parameters describing the end-QRS activity and fragmentation index M and score S describing the whole QRS complex were computed. Fragmentation and time-domain parameters differed between the VT and control groups: fragmentation index M was 12 +/- 3 versus 9 +/- 2 (P <0.001), fragmentation score S was 83 +/- 42 versus 56 +/- 21 (P < 0.001), and filtered QRS duration was 144 +/- 32 versus 114 +/- 19 ms (P < 0.001) in VT and control groups, respectively. A combination of fragmentation parameters yielded 87% sensitivity and 61% specificity in VT identification. Corresponding figures for a time-domain parameter combination were 81% and 72%. Sensitivity of time-domain analysis was 88% and specificity was 75% in a subgroup with anterior MI. In multivariate analysis, fragmentation and time-domain analyses discriminated VT patients from controls independently of the extent of coronary artery disease or left ventricular dysfunction. MCG in postinfarction patients reveals pathology associated with propensity to ventricular arrhythmias inside and not only at the end of the QRS complex. MCG seems most accurate in the anterior infarct location. PMID:11523602

  12. A statistical index for early diagnosis of ventricular arrhythmia from the trend analysis of ECG phase-portraits.

    PubMed

    Cappiello, Grazia; Das, Saptarshi; Mazomenos, Evangelos B; Maharatna, Koushik; Koulaouzidis, George; Morgan, John; Puddu, Paolo Emilio

    2015-01-01

    In this paper, we propose a novel statistical index for the early diagnosis of ventricular arrhythmia (VA) using the time delay phase-space reconstruction (PSR) technique, from the electrocardiogram (ECG) signal. Patients with two classes of fatal VA-with preceding ventricular premature beats (VPBs) and with no VPBs-have been analysed using extensive simulations. Three subclasses of VA with VPBs viz. ventricular tachycardia (VT), ventricular fibrillation (VF) and VT followed by VF are analyzed using the proposed technique. Measures of descriptive statistics like mean (µ), standard deviation (σ), coefficient of variation (CV = σ/µ), skewness (γ) and kurtosis (β) in phase-space diagrams are studied for a sliding window of 10 beats of the ECG signal using the box-counting technique. Subsequently, a hybrid prediction index which is composed of a weighted sum of CV and kurtosis has been proposed for predicting the impending arrhythmia before its actual occurrence. The early diagnosis involves crossing the upper bound of a hybrid index which is capable of predicting an impending arrhythmia 356 ECG beats, on average (with 192 beats standard deviation) before its onset when tested with 32 VA patients (both with and without VPBs). The early diagnosis result is also verified using a leave one out cross-validation (LOOCV) scheme with 96.88% sensitivity, 100% specificity and 98.44% accuracy. PMID:25500749

  13. Inhibition of Cardiac Ca2+ Release Channels (RyR2) Determines Efficacy of Class I Antiarrhythmic Drugs in Catecholaminergic Polymorphic Ventricular Tachycardia

    PubMed Central

    Hwang, Hyun Seok; Hasdemir, Can; Laver, Derek; Mehra, Divya; Turhan, Kutsal; Faggioni, Michela; Yin, Huiyong; Knollmann, Björn C.

    2013-01-01

    Background Catecholaminergic polymorphic ventricular tachycardia (CPVT) is caused by mutations in the cardiac ryanodine receptor (RyR2) or calsequestrin (Casq2) and can be difficult to treat. The class Ic antiarrhythmic drug flecainide blocks RyR2 channels and prevents CPVT in mice and humans. It is not known whether other class I antiarrhythmic drugs also block RyR2 channels and to what extent RyR2 channel inhibition contributes to antiarrhythmic efficacy in CPVT. Methods and Results We first measured the effect of all class I antiarrhythmic drugs marketed in the United States (quinidine, procainamide, disopyramide, lidocaine, mexiletine, flecainide, and propafenone) on single RyR2 channels incorporated into lipid bilayers. Only flecainide and propafenone inhibited RyR2 channels, with the S-enantiomer of propafenone having a significantly lower potency than R-propafenone or flecainide. In Casq2−/− myocytes, the propafenone enantiomers and flecainide significantly reduced arrhythmogenic Ca2+ waves at clinically relevant concentrations, whereas Na+ channel inhibitors without RyR2 blocking properties did not. In Casq2−/− mice, 5 mg/kg R-propafenone or 20 mg/kg S-propafenone prevented exercise-induced CPVT, whereas procainamide (20 mg/kg) or lidocaine (20 mg/kg) were ineffective (n=5 to 9 mice, P<0.05). QRS duration was not significantly different, indicating a similar degree of Na+ channel inhibition. Clinically, propafenone (900 mg/d) prevented ICD shocks in a 22-year-old CPVT patient who had been refractory to maximal standard drug therapy and bilateral stellate ganglionectomy. Conclusions RyR2 cardiac Ca2+ release channel inhibition appears to determine efficacy of class I drugs for the prevention of CPVT in Casq2−/− mice. Propafenone may be an alternative to flecainide for CPVT patients symptomatic on β-blockers. PMID:21270101

  14. 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

  15. Increased Ca2+ sensitivity of the ryanodine receptor mutant RyR2R4496C underlies catecholaminergic polymorphic ventricular tachycardia.

    PubMed

    Fernández-Velasco, María; Rueda, Angélica; Rizzi, Nicoletta; Benitah, Jean-Pierre; Colombi, Barbara; Napolitano, Carlo; Priori, Silvia G; Richard, Sylvain; Gómez, Ana María

    2009-01-30

    Cardiac ryanodine receptor (RyR2) mutations are associated with autosomal dominant catecholaminergic polymorphic ventricular tachycardia, suggesting that alterations in Ca(2+) handling underlie this disease. Here we analyze the underlying Ca(2+) release defect that leads to arrhythmia in cardiomyocytes isolated from heterozygous knock-in mice carrying the RyR2(R4496C) mutation. RyR2(R4496C-/-) littermates (wild type) were used as controls. [Ca(2+)](i) transients were obtained by field stimulation in fluo-3-loaded cardiomyocytes and viewed using confocal microscopy. In our basal recording conditions (2-Hz stimulation rate), [Ca(2+)](i) transients and sarcoplasmic reticulum Ca(2+) load were similar in wild-type and RyR2(R4496C) cells. However, paced RyR2(R4496C) ventricular myocytes presented abnormal Ca(2+) release during the diastolic period, viewed as Ca(2+) waves, consistent with the occurrence of delayed afterdepolarizations. The occurrence of this abnormal Ca(2+) release was enhanced at faster stimulation rates and by beta-adrenergic stimulation, which also induced triggered activity. Spontaneous Ca(2+) sparks were more frequent in RyR2(R4496C) myocytes, indicating increased RyR2(R4496C) activity. When permeabilized cells were exposed to different cytosolic [Ca(2+)](i), RyR2(R4496C) showed a dramatic increase in Ca(2+) sensitivity. Isoproterenol increased [Ca(2+)](i) transient amplitude and Ca(2+) spark frequency to the same extent in wild-type and RyR2(R4496C) cells, indicating that the beta-adrenergic sensitivity of RyR2(R4496C) cells remained unaltered. This effect was independent of protein expression variations because no difference was found in the total or phosphorylated RyR2 expression levels. In conclusion, the arrhythmogenic potential of the RyR2(R4496C) mutation is attributable to the increased Ca(2+) sensitivity of RyR2(R4496C), which induces diastolic Ca(2+) release and lowers the threshold for triggered activity. PMID:19096022

  16. Reprint of 'Model of unidirectional block formation leading to reentrant ventricular tachycardia in the infarct border zone of postinfarction canine hearts'

    PubMed Central

    Ciaccio, Edward J.; Coromilas, James; Ashikaga, Hiroshi; Cervantes, Daniel O.; Wit, Andrew L.; Peters, Nicholas S.; McVeigh, Elliot R.; Garan, Hasan

    2015-01-01

    Background When the infarct border zone is stimulated prematurely, a unidirectional block line (UBL) can form and lead to double-loop (figure-of-eight) reentrant ventricular tachycardia (VT) with a central isthmus. The isthmus is composed of an entrance, center, and exit. It was hypothesized that for certain stimulus site locations and coupling intervals, the UBL would coincide with the isthmus entrance boundary, where infarct border zone thickness changes from thin-to-thick in the travel direction of the premature stimulus wavefront. Method A quantitative model was developed to describe how thin-to-thick changes in the border zone result in critically convex wavefront curvature leading to conduction block, which is dependent upon coupling interval. The model was tested in 12 retrospectively analyzed postinfarction canine experiments. Electrical activation was mapped for premature stimulation and for the first reentrant VT cycle. The relationship of functional conduction block forming during premature stimulation to functional block during reentrant VT was quantified. Results For an appropriately placed stimulus, in accord with model predictions: 1. The UBL and reentrant VT isthmus lateral boundaries overlapped (error: 4.8±5.7 mm). 2. The UBL leading edge coincided with the distal isthmus where the center-entrance boundary would be expected to occur. 3. The mean coupling interval was 164.6±11.0 ms during premature stimulation and 190.7±20.4 ms during the first reentrant VT cycle, in accord with model calculations, which resulted in critically convex wavefront curvature and functional conduction block, respectively, at the location of the isthmus entrance boundary and at the lateral isthmus edges. Discussion Reentrant VT onset following premature stimulation can be explained by the presence of critically convex wavefront curvature and unidirectional block at the isthmus entrance boundary when the premature stimulation interval is sufficiently short. The double

  17. Catheter Ablation of Ventricular Tachycardia

    MedlinePlus

    ... like to see the Circulation web site. Your Personal Message Send Message ... Scholar Cited By... Cardiac tachyarrhythmias and patient values and preferences for their management: the European Heart ...

  18. Larger low voltage zone in endocardial unipolar map compared with that in epicardial bipolar map indicates difficulty in eliminating ventricular tachycardia by catheter ablation.

    PubMed

    Miyamoto, Koji; Noda, Takashi; Satomi, Kazuhiro; Wada, Mitsuru; Nakajima, Ikutaro; Ishibashi, Kohei; Okamura, Hideo; Noguchi, Teruo; Anzai, Toshihisa; Yasuda, Satoshi; Ogawa, Hisao; Shimizu, Wataru; Aiba, Takeshi; Kamakura, Shiro; Kusano, Kengo

    2016-08-01

    Patients with ischemic and non-ischemic cardiomyopathy often have substrate for ventricular tachycardia (VT) in the endocardium (ENDO), epicardium (EPI), and/or intramural. Although it has been reported that the ENDO unipolar (UNI) voltage map is useful in detecting EPI substrate, its feasibility to detect intramural scarring and its usefulness in radiofrequency catheter ablation (RFCA) remain unclear. To assess the relationship between the left ventricle (LV) ENDO UNI voltage map and the LV EPI bipolar (BIP) voltage map, and to determine the usefulness of the ENDO UNI voltage map to guide RFCA for VT in patients with cardiomyopathy undergoing combined ENDO- and EPI RFCA. Eleven patients with VT undergoing detailed ENDO and EPI electroanatomical mapping of the LV were included (mean age 59 ± 11 years, 9 men). We assessed the value of the LV ENDO UNI voltage map in identifying EPI and/or intramural substrate in these 11 patients with non-ischemic or ischemic cardiomyopathy. The underlying heart disease was dilated cardiomyopathy in 4 patients, cardiac sarcoidosis in 3, hypertrophic cardiomyopathy in 2, and ischemic heart disease in 2 patients. The mean LV ejection fraction was 24 ± 7 %. The low voltage zone (LVZ) was defined as <1.5 mV for LV ENDO BIP electrograms (EGMs), <8.3 mV for LV ENDO UNI EGMs, and <1.0 mV for LV EPI BIP EGMs. The surface area of each LVZ was measured. We also measured the LVZ of the spatial overlap between ENDO UNI and EPI BIP voltage maps using the transparency mode on CARTO software. We performed RFCA at the ENDO and EPI based on activation and/or substrate maps, targeting the LVZ and/or abnormal EGMs. The LVZ was present in the LV ENDO BIP voltage map in 10 of 11 patients (42 ± 33 cm(2)), and in the LV ENDO UNI voltage map in 10 of 11 patients (72 ± 45 cm(2)). The LVZ was present in the EPI BIP voltage map in 9 of 11 patients (70 ± 61 cm(2)), and the LVZ in the ENDO UNI voltage map was also seen in all 9 patients

  19. Studies in a newborn infant with supraventricular tachycardia and Wolff-Parkinson-White syndrome.

    PubMed Central

    Kaye, H H; Reid, D S; Tynan, M

    1975-01-01

    A neonatal patient with Wolff-Parkinson-White type A and supraventricular tachycardia is described. Demonstration of the mechanism of the tachycardia and its termination were achieved using intracardiac electrography and cardiac pacing. Quantitative left ventricular angiography and echocardiography showed impaired left ventricular function following the arrhythmia. Serial echocardiograms demonstrated the subsequent return to normal left ventricular performance. Images PMID:1138737

  20. What About Tachycardia-induced Cardiomyopathy?

    PubMed Central

    Ellis, Ethan R; Josephson, Mark E

    2013-01-01

    Long-standing tachycardia is a well-recognised cause of heart failure and left ventricular dysfunction, and has led to the nomenclature, tachycardia-induced cardiomyopathy (TIC). TIC is generally a reversible cardiomyopathy if the causative tachycardia can be treated effectively, either with medications, surgery or catheter ablation. The diagnosis is usually made after demonstrating recovery of left ventricular function with normalisation of heart rate in the absence of other identifiable aetiologies. One hundred years after the first reported case of TIC, our understanding of the pathophysiology of TIC in humans remains limited despite extensive work in animal models of TIC. In this review we will discuss the proposed mechanisms of TIC, the causative tachyarrhythmias and their treatment, outcomes for patients diagnosed with TIC, and future directions for research and clinical care. PMID:26835045

  1. What About Tachycardia-induced Cardiomyopathy?

    PubMed

    Ellis, Ethan R; Josephson, Mark E

    2013-11-01

    Long-standing tachycardia is a well-recognised cause of heart failure and left ventricular dysfunction, and has led to the nomenclature, tachycardia-induced cardiomyopathy (TIC). TIC is generally a reversible cardiomyopathy if the causative tachycardia can be treated effectively, either with medications, surgery or catheter ablation. The diagnosis is usually made after demonstrating recovery of left ventricular function with normalisation of heart rate in the absence of other identifiable aetiologies. One hundred years after the first reported case of TIC, our understanding of the pathophysiology of TIC in humans remains limited despite extensive work in animal models of TIC. In this review we will discuss the proposed mechanisms of TIC, the causative tachyarrhythmias and their treatment, outcomes for patients diagnosed with TIC, and future directions for research and clinical care. PMID:26835045

  2. [Atrial tachycardia ablated from the non-coronary aortic cusp].

    PubMed

    Baszko, Artur; Krzyzanowski, Krzysztof; Zinka, Elzbieta; Grajek, Stefan

    2007-02-01

    We present a case of a patient with drug resistant atrial tachycardia which was ablated from the noncoronary aortic cusp. Tachycardia was adenosine-sensitive and was characterized by a long RP' interval and low amplitude P waves (biphasic in II, III, aVF and V1-V2 leads, and positive in aVL). The earliest atrial activation during tachycardia was recorded at His region and from non-coronary aortic sinus of Valsalva. RF ablation at this area terminated tachycardia and did not impair atrio-ventricular conduction. PMID:17366369

  3. Autoimmune Basis for Postural Tachycardia Syndrome

    ClinicalTrials.gov

    2016-03-30

    Postural Orthostatic Tachycardia Syndrome; Postural Tachycardia Syndrome; Tachycardia; Arrhythmias, Cardiac; Autonomic Nervous System Diseases; Orthostatic Intolerance; Cardiovascular Diseases; Primary Dysautonomias

  4. A Feasibility Study for Perioperative Ventricular Tachycardia Prognosis and Detection and Noise Detection Using a Neural Network and Predictive Linear Operators

    NASA Technical Reports Server (NTRS)

    Moebes, T. A.

    1994-01-01

    To locate the accessory pathway(s) in preexicitation syndromes, epicardial and endocardial ventricular mapping is performed during anterograde ventricular activation via accessory pathway(s) from data originally received in signal form. As the number of channels increases, it is pertinent that more automated detection of coherent/incoherent signals is achieved as well as the prediction and prognosis of ventricular tachywardia (VT). Today's computers and computer program algorithms are not good in simple perceptual tasks such as recognizing a pattern or identifying a sound. This discrepancy, among other things, has been a major motivating factor in developing brain-based, massively parallel computing architectures. Neural net paradigms have proven to be effective at pattern recognition tasks. In signal processing, the picking of coherent/incoherent signals represents a pattern recognition task for computer systems. The picking of signals representing the onset ot VT also represents such a computer task. We attacked this problem by defining four signal attributes for each potential first maximal arrival peak and one signal attribute over the entire signal as input to a back propagation neural network. One attribute was the predicted amplitude value after the maximum amplitude over a data window. Then, by using a set of known (user selected) coherent/incoherent signals, and signals representing the onset of VT, we trained the back propagation network to recognize coherent/incoherent signals, and signals indicating the onset of VT. Since our output scheme involves a true or false decision, and since the output unit computes values between 0 and 1, we used a Fuzzy Arithmetic approach to classify data as coherent/incoherent signals. Furthermore, a Mean-Square Error Analysis was used to determine system stability. The neural net based picking coherent/incoherent signal system achieved high accuracy on picking coherent/incoherent signals on different patients. The system

  5. 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.

  6. Spontaneous Transition of Double Tachycardias with Atrial Fusion in a Patient with Wolff-Parkinson-White Syndrome

    PubMed Central

    Kim, Dongmin

    2016-01-01

    Among patients with Wolff-Parkinson-White syndrome, atrioventricular reciprocating tachycardia (AVRT) and atrioventricular nodal reentrant tachycardia (AVNRT) can coexist in a single patient. Direct transition of both tachycardias is rare; however, it can occur after premature atrial or ventricular activity if the cycle lengths of the two tachycardias are similar. Furthermore, persistent atrial activation by an accessory pathway (AP) located outside of the AV node during ongoing AVNRT is also rare. This article describes a case of uncommon atrial activation by an AP during AVNRT and gradual transition of the two supraventricular tachycardias without any preceding atrial or ventricular activity in a patient with preexcitation syndrome. PMID:27482269

  7. Update: Arrhythmias (V). Paroxysmal supraventricular tachycardias and preexcitation syndromes.

    PubMed

    Almendral, Jesús; Castellanos, Eduardo; Ortiz, Mercedes

    2012-05-01

    Paroxysmal supraventricular tachycardias are fast and usually regular rhythms that require some structure above the bifurcation of the His bundle to be continued. The 3 most common types are atrial tachycardias, atrioventricular nodal reentrant tachycardias, and tachycardias mediated by an accessory pathway. The last two varieties are discussed in the present manuscript. Their prognosis is benign regarding life expectancy but typically they are symptomatic and chronically recurrent, producing a certain disability. They usually occur in people without structural heart disease. Pharmacologic therapy is possible, but given the high efficacy of catheter ablation, these procedures are frequently chosen. Ventricular preexcitation is due to the presence of an accessory pathway, usually atrioventricular. The clinical course can be asymptomatic, generating a characteristic electrocardiographic pattern, produce paroxysmal supraventricular tachycardias, or facilitate other types of arrhythmias. Very rarely, they can cause sudden cardiac death. The treatment of choice for symptomatic patients is catheter ablation of the accessory pathway. The therapeutic attitude towards asymptomatic preexcitation remains controversial. PMID:22459483

  8. Accurate means of detecting and characterizing abnormal patterns of ventricular activation by phase image analysis

    SciTech Connect

    Botvinick, E.H.; Frais, M.A.; Shosa, D.W.; O'Connell, J.W.; Pacheco-Alvarez, J.A.; Scheinman, M.; Hattner, R.S.; Morady, F.; Faulkner, D.B.

    1982-08-01

    The ability of scintigraphic phase image analysis to characterize patterns of abnormal ventricular activation was investigated. The pattern of phase distribution and sequential phase changes over both right and left ventricular regions of interest were evaluated in 16 patients with normal electrical activation and wall motion and compared with those in 8 patients with an artificial pacemaker and 4 patients with sinus rhythm with the Wolff-Parkinson-White syndrome and delta waves. Normally, the site of earliest phase angle was seen at the base of the interventricular septum, with sequential change affecting the body of the septum and the cardiac apex and then spreading laterally to involve the body of both ventricles. The site of earliest phase angle was located at the apex of the right ventricle in seven patients with a right ventricular endocardial pacemaker and on the lateral left ventricular wall in one patient with a left ventricular epicardial pacemaker. In each case the site corresponded exactly to the position of the pacing electrode as seen on posteroanterior and left lateral chest X-ray films, and sequential phase changes spread from the initial focus to affect both ventricles. In each of the patients with the Wolff-Parkinson-White syndrome, the site of earliest ventricular phase angle was located, and it corresponded exactly to the site of the bypass tract as determined by endocardial mapping. In this way, four bypass pathways, two posterior left paraseptal, one left lateral and one right lateral, were correctly localized scintigraphically. On the basis of the sequence of mechanical contraction, phase image analysis provides an accurate noninvasive method of detecting abnormal foci of ventricular activation.

  9. Endocrine activation in tachycardias.

    PubMed

    Lukac, P; Lukacova, S; Vigas, M; Hatala, R

    2001-01-01

    This article reviews the complex character of neuroendocrine response to paroxysmal tachycardia. While the endocrine influences in arrhythmogenesis are well perceived by the cardiologists, less attention has been paid to influence of tachycardia on neuroendocrine activation. However, this may significantly alter the clinical course of tachycardias and its responses to pharmacotherapeutic interventions. Main characteristics of hormones with direct relationship to cardiovascular system (ANP, AVP, catecholamines, angiotensin and others) are listed with description of regulation of their secretion and main biological effects, especially with regard to regulation of circulation. Changes in hemodynamics during tachycardia with accompanying changes in ANP, AVP renin-angiotensin-aldosterone system, sympatho-neural and sympatho-adrenal activation are reviewed. Further research and understanding require more complex approach and concentration on interrelationship of different regulatory hormones in tachycardia. (Fig. 2, Ref. 96.) PMID:11763674

  10. The value of electrocardiography for differential diagnosis in wide QRS complex tachycardia.

    PubMed

    Sousa, Pedro A; Pereira, Salomé; Candeias, Rui; de Jesus, Ilídio

    2014-03-01

    Correct diagnosis in wide QRS complex tachycardia remains a challenge. Differential diagnosis between ventricular and supraventricular tachycardia has important therapeutic and prognostic implications, and although data from clinical history and physical examination may suggest a particular origin, it is the 12-lead surface electrocardiogram that usually enables this differentiation. Since 1978, various electrocardiographic criteria have been proposed for the differential diagnosis of wide complex tachycardias, particularly the presence of atrioventricular dissociation, and the axis, duration and morphology of QRS complexes. Despite the wide variety of criteria, diagnosis is still often difficult, and errors can have serious consequences. To reduce such errors, several differential diagnosis algorithms have been proposed since 1991. However, in a small percentage of wide QRS tachycardias the diagnosis remains uncertain and in these the wisest decision is to treat them as ventricular tachycardias. The authors' objective was to review the main electrocardiographic criteria and differential diagnosis algorithms of wide QRS tachycardia. PMID:24656320

  11. Cardiomyopathy induced by sinus tachycardia in combat wounded: a case study.

    PubMed

    Kavanaugh, Michael; McDivitt, Jonathan; Philip, Andrew; Froehner, Jerald W; Rotruck, John; Hemann, Brian; Haigney, Mark; Atwood, John; Nations, Joel Anthony

    2014-09-01

    Tachycardia induced cardiomyopathy is a potentially lethal cause of heart failure generally because of atrial tachycardia and less frequently ventricular tachycardia. We present two cases of Marines with severe traumatic blast injuries secondary to improvised explosive device attacks whose hospital courses included amputation, massive blood transfusions, and multiple surgeries. Both patients had prolonged sinus tachycardia averaging >110 beats per minute and developed depressed left ventricular function, which recovered when treated with β blockers. Sinus tachycardia is often considered a physiological response to stress, and the purpose of this manuscript is to describe the cardiac injury apparently related to a prolonged stress response. In addition, the literature does not clearly recommend controlling heart rates in trauma patients with persistent sinus tachycardia, but it is a therapeutic option that should be considered by providers. PMID:25181728

  12. Dabigatran for left ventricular thrombus.

    PubMed

    Kolekar, Satishkumar; Munjewar, Chandrashekhar; Sharma, Satyavan

    2015-01-01

    Male patient in dilated phase of hypertrophic cardiomyopathy had multiple hospitalizations during the past 2 years either due to congestive heart failure, stroke, scar epilepsy, or atrial fibrillation and ventricular tachycardia. Medication included evidence based therapy for heart failure, cordarone and warfarin. Anticoagulation had to be discontinued due to marked fluctuations in INR. Transthoracic Echocardiography (TTE) revealed a mobile mass in the left ventricle. He was treated with Dabigatran 110mg twice a day for 4 months without any bleeding or embolic episode and complete resolution of thrombus. Dabigatran is a reversible direct thrombin inhibitor and currently approved for the prevention of thromboembolic episodes in non-valvar atrial fibrillation. This case demonstrates possible thrombolytic properties of dabigatran in resolution of left ventricular thrombus. PMID:26432747

  13. Drug-induced narrowing of the width of the zone of entrainment as a predictor of the subsequent non-inducibility of reentrant ventricular tachycardia after an additional dose of an antiarrhythmic drug.

    PubMed Central

    Aizawa, Y.; Chinushi, M.; Naitoh, N.; Shibata, A.

    1996-01-01

    BACKGROUND: The efficacy of drugs used to treat inducible monomorphic sustained ventricular tachycardia (VT) has been assessed by investigating their ability to suppress inducibility, but the mechanism of the drug action remains to be determined. OBJECTIVES: To determine electrophysiological variables that predict inducibility, divided doses of class I antiarrhythmic drugs were given and their effects were analysed, particularly the ability of the final dose to suppress inducibility. METHODS: The excitable gap was estimated by the zone of entrainment, which was defined as the difference between the cycle length of VT and the longest paced cycle length that interrupted VT during entrainment of VT with rapid pacing at paced cycle lengths in decrements of 10 ms. The cycle length of VT, the block cycle length, and the zone of entrainment were measured in the drug free state and after intermediate and final doses of procainamide, disopyramide, cibenzoline, and mexiletine. RESULTS: Sustained monomorphic VT with a mean (SD) cycle length of 285 (43) ms was induced in 8 patients. It was entrained and interrupted at the block cycle length of 231 (31) ms. The width of the zone of entrainment was 54 (23) ms. In 8 studies VT was not inducible at final doses of procainamide in 4, cibenzoline in 1, and mexiletine in 3. In another 10 studies (procainamide in 4, disopyramide in 1, cibenzoline in 2, and mexiletine in 3), VT remained inducible at the intermediate dose and at the final dose. The cycle length of VT was prolonged to a similar degree in studies of effective and ineffective drugs, but the cycle length that blocked VT was longer at the intermediate dose of the effective drugs. Consequently, the width of the zone of entrainment was significantly narrowed at the intermediate dose of effective drugs and the width of the zone of entrainment was narrower than when ineffective drugs were given (22 (13) ms v 76 (18) or 75 (37) ms at the intermediate and final doses respectively

  14. Paroxysmal supraventricular tachycardia (PSVT)

    MedlinePlus

    PSVT; Supraventricular tachycardia; Abnormal heart rhythm - PSVT; Arrhythmia - PSVT; Rapid heart rate - PSVT; Fast heart rate - PSVT ... Normally, the chambers of the heart (atria and ventricles) contract in ... are caused by an electrical signal that begins in an area ...

  15. Multifocal atrial tachycardia

    MedlinePlus

    ... atrial tachycardia (MAT), many locations in the atria fire signals at the same time. Too many signals ... people with conditions that lower the amount of oxygen in the blood. These conditions include: Bacterial pneumonia ...

  16. Torsade de pointes tachycardia as a rare manifestation of acute enteroviral myocarditis

    PubMed Central

    Badorff, C; Zeiher, A; Hohnloser, S

    2001-01-01

    A patient with cardiac arrest and documented torsade de pointes ventricular tachycardia is presented in whom acute coxsackievirus B2 myocarditis was identified as the most likely underlying cardiac condition. This case shows that torsade de pointes may occur as a rare manifestation of viral myocarditis. Serial serological tests and endomyocardial biopsies may be helpful in establishing a diagnosis in such patients.


Keywords: torsade de pointes; ventricular tachycardia; viral myocarditis PMID:11602535

  17. Postural Orthostatic Tachycardia Syndrome

    PubMed Central

    2014-01-01

    The postural orthostatic tachycardia syndrome is a disease characterized by excessively increased heart rate during orthostatic challenge associated with symptoms of orthostatic intolerance including dizziness, exercise intolerance, headache, fatigue, memory problems, nausea, blurred vision, pallor, and sweating, which improve with recumbence. Postural orthostatic tachycardia syndrome patients may present with a multitude of additional symptoms that are attributable to vascular vasoconstriction. Observed signs and symptoms in a patient with postural orthostatic tachycardia syndrome include tachycardia at rest, exaggerated heart rate increase with upright position and exercise, crushing chest pain, tremor, syncope, loss of vision, confusion, migraines, fatigue, heat intolerance, parasthesia, dysesthesia, allodynia, altered traditional senses, and thermoregulatory abnormalities. There are a number of possible dermatological manifestations of postural orthostatic tachycardia syndrome easily explained by its recently discovered pathophysiology. The author reports the case of a 22-year-old woman with moderate-to-severe postural orthostatic tachycardia syndrome with numerous dermatological manifestations attributable to the disease process. The cutaneous manifestations observed in this patient are diverse and most noticeable during postural orthostatic tachycardia syndrome flares. The most distinct are evanescent, hyperemic, sharply demarcated, irregular patches on the chest and neck area that resolve upon diascopy. This distinct “evanescent hyperemia” disappears spontaneously after seconds to minutes and reappears unexpectedly. Other observed dermatological manifestations of this systemic disease include Raynaud’s phenomenon, koilonychia, onychodystrophy, madarosis, dysesthesia, allodynia, telogen effluvium, increased capillary refill time, and livedo reticularis. The treatment of this disease poses a great challenge. The author reports the unprecedented use of an

  18. Analysis of regional left ventricular wall movement by phased array echocardiography.

    PubMed Central

    Gibson, D G; Brown, D J; Logan-Sinclair, R B

    1978-01-01

    Images from standard two-dimensional echocardiographs do not lend themselves to the study of regional left ventricular wall movement because of poor definition of endocardium. An alternative method, based on a wide-angle phased array sector scanner has, therefore, been devised. Once the appropriate region of the heart has been identified, the scan rate is increased, and an array of 41 M-mode scans is produced, resulting in improved frequency response and endocardial definition. Each scan is digitised separately, and since their spatial orientation is known, the left ventricular image can be reconstituted by computer, and isometric or contour displays produced. Preliminary results, based on 40 patients, are presented showing examples of left ventricular wall movement. Regional abnormalities of amplitude or timing can be displayed with results similar to those of angiography, while disturbances of septal motion or wall thickness can be observed in greater detail than with other methods. Images PMID:737090

  19. Mechanism, diagnosis, and treatment of outflow tract tachycardia.

    PubMed

    Lerman, Bruce B

    2015-10-01

    Idiopathic ventricular arrhythmia is a generic term for a spectrum of arrhythmias that occur in the absence of structural heart disease or ion channelopathy. These arrhythmias include monomorphic premature ventricular contractions (PVCs), nonsustained monomorphic ventricular tachycardia (VT), and sustained VT. Most idiopathic ventricular arrhythmias originate from the right and left ventricular outflow tracts and include sites accessed from the aortic sinuses of Valsalva. Outflow tract arrhythmia is identified by an electrocardiographic pattern consistent with a left bundle branch block inferior axis morphology. Characteristically, outflow tract VT is caused by cAMP-mediated triggered activity, and is terminated by administration of adenosine. Outflow tract arrhythmias are focal and, therefore, are readily amenable to definitive treatment with catheter-based radiofrequency ablation. Although arrhythmia might be associated with reversible PVC-mediated cardiomyopathy, and infrequently with PVC-induced polymorphic VT or ventricular fibrillation, prognosis is generally favourable. PMID:26283265

  20. Arrhythmogenic right ventricular cardiomyopathy/dysplasia.

    PubMed

    Thiene, Gaetano; Corrado, Domenico; Basso, Cristina

    2007-01-01

    Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a heart muscle disease clinically characterized by life-threatening ventricular arrhythmias. Its prevalence has been estimated to vary from 1:2,500 to 1:5,000. ARVC/D is a major cause of sudden death in the young and athletes. The pathology consists of a genetically determined dystrophy of the right ventricular myocardium with fibro-fatty replacement to such an extent that it leads to right ventricular aneurysms. The clinical picture may include: a subclinical phase without symptoms and with ventricular fibrillation being the first presentation; an electrical disorder with palpitations and syncope, due to tachyarrhythmias of right ventricular origin; right ventricular or biventricular pump failure, so severe as to require transplantation. The causative genes encode proteins of mechanical cell junctions (plakoglobin, plakophilin, desmoglein, desmocollin, desmoplakin) and account for intercalated disk remodeling. Familiar occurrence with an autosomal dominant pattern of inheritance and variable penetrance has been proven. Recessive variants associated with palmoplantar keratoderma and woolly hair have been also reported. Clinical diagnosis may be achieved by demonstrating functional and structural alterations of the right ventricle, depolarization and repolarization abnormalities, arrhythmias with the left bundle branch block morphology and fibro-fatty replacement through endomyocardial biopsy. Two dimensional echo, angiography and magnetic resonance are the imaging tools for visualizing structural-functional abnormalities. Electroanatomic mapping is able to detect areas of low voltage corresponding to myocardial atrophy with fibro-fatty replacement. The main differential diagnoses are idiopathic right ventricular outflow tract tachycardia, myocarditis, dialted cardiomyopathy and sarcoidosis. Only palliative therapy is available and consists of antiarrhythmic drugs, catheter ablation and

  1. Noninvasive mapping of ventricular arrhythmias.

    PubMed

    Shah, Ashok J; Lim, Han S; Yamashita, Seigo; Zellerhoff, Stephan; Berte, Benjamin; Mahida, Saagar; Hooks, Darren; Aljefairi, Nora; Derval, Nicolas; Denis, Arnaud; Sacher, Frédéric; Jais, Pierre; Dubois, Rémi; Hocini, Meleze; Haissaguerre, Michel

    2015-03-01

    Several decades of research has led to the development of a 252-lead electrocardiogram-based three-dimensional imaging modality to refine noninvasive diagnosis and improve the management of heart rhythm disorders. This article reviews the clinical potential of this noninvasive mapping technique in identifying the sources of electrical disorders and guiding the catheter ablation of ventricular arrhythmias (premature ventricular beats and ventricular tachycardia). The article also briefly refers to the noninvasive electrical imaging of the arrhythmogenic ventricular substrate based on the electrophysiologic characteristics of postinfarction ventricular myocardium. PMID:25784026

  2. Irregular Wide Complex Tachycardia in a Young Man.

    PubMed

    Rochlani, Yogita; Pothineni, Naga Venkata; Paydak, Hakan

    2016-02-01

    Wolf Parkinson White syndrome is a pre-excitation syndrome due to an accessory conduction pathway. Electrocardiography demonstrates a short PR interval, long QRS interval and delta waves in normal sinus rhythm. Atrial fibrillation with underlying Wolf Parkinson White syndrome presents with irregular wide complex tachycardia, and can cause sudden cardiac death by precipitating ventricular fibrillation. Irregular wide complex tachycardia may be the first presentation of this underlying conduction abnormality in young patients. Emergency management for irregular wide complex tachycardia in hemodynamically unstable patients involves synchronized cardioversion, while intra-venous Procainamide can be used in hemodynamically stable patients. AV nodal blocking agents should be avoided. Treatment of choice for WPW syndrome is radiofrequency ablation. PMID:26939470

  3. Aprindine for treatment of ventricular arrhythmias in the dog.

    PubMed

    Muir, W W; Bonagura, J D

    1982-10-01

    Aprindine hydrochloride was administered IV and orally to 20 dogs with ventricular tachycardia. Seventeen of the 20 dogs had been unsuccessfully treated with conventional antiarrhythmic drugs. Fifteen of the 20 dogs converted to sinus rhythm after IV aprindine therapy, 4 dogs demonstrated marked slowing of their ventricular tachycardia, and 1 dog showed an increase in the rate of ventricular tachycardia. Emesis, ataxia, salivation, and nystamus were observed in 7 dogs after IV aprindine therapy. One dog developed clinical and laboratory evidence compatible with acute hepatitis. PMID:7149383

  4. Implantable Cardioverter-Defibrillator Shock Caused by Uncommon Variety of Nonreentrant Atrioventricular Nodal Tachycardia.

    PubMed

    Singh, David K; Badhwar, Nitish

    2016-03-01

    This article reports a typical case of incessant double-fire tachycardia resulting in implantable cardioverter-defibrillator discharge caused by the device's misdiagnosis of ventricular tachycardia. At electrophysiology study, the presence of double-fire physiology was confirmed, and modification of the slow pathway resulted in elimination of repetitive double fires. Although this is an unusual entity, it is important to recognize, because it may be misdiagnosed as atrial fibrillation, resulting in inappropriate anticoagulation and/or antiarrhythmic therapy. Modification of the slow pathway and elimination of double-fire physiology can result in marked improvement in quality of life and reversal of tachycardia-mediated cardiomyopathy. PMID:26920170

  5. Recognizing postural orthostatic tachycardia syndrome.

    PubMed

    Pavlik, Daniel; Agnew, Donna; Stiles, Lauren; Ditoro, Rachel

    2016-04-01

    This article describes the pathophysiology, clinical presentation, differential diagnosis, diagnosis, and management of postural orthostatic tachycardia syndrome (POTS), a potentially debilitating autonomic disorder that can have many causes and presentations. POTS can be mistaken for panic disorder, inappropriate sinus tachycardia, and chronic fatigue syndrome. Clinician suspicion for the syndrome is key to prompt patient diagnosis and treatment. PMID:26967958

  6. Induction of ventricular fibrillation predicts sudden death in patients treated with amiodarone because of ventricular tachyarrhythmias after a myocardial infarction.

    PubMed Central

    Rodríguez, L. M.; Sternick, E. B.; Smeets, J. L.; Timmermans, C.; den Dulk, K.; Oreto, G.; Wellens, H. J.

    1996-01-01

    OBJECTIVE--To examine the value of programmed electrical stimulation of the heart in predicting sudden death in patients receiving amiodarone to treat ventricular tachyarrhythmias after myocardial infarction. DESIGN--Consecutive patients; retrospective study. SETTING--Referral centre for cardiology, academic hospital. PATIENTS--106 patients with ventricular tachycardia (n = 77) or ventricular fibrillation (n = 29) late after myocardial infarction. INTERVENTIONS--Programmed electrical stimulation was performed while on amiodarone treatment for at least one month. MEASUREMENTS AND MAIN RESULTS--In 80/106 patients either ventricular fibrillation (n = 15) or sustained monomorphic ventricular tachycardia (n = 65) was induced. After a mean follow up of 50 (SD 40) months (1-144), 11 patients died suddenly and two used their implantable cardioverter debfibrillator. By multivariate analysis two predictors for sudden death were found: (1) inducibility of ventricular fibrillation under amiodarone treatment (P << 0.001), and (2) a left ventricular ejection fraction of < 40% (P < 0.05). The survival rate at one, two, three, and five years was 70%, 62%, 62%, and 40% respectively for patients in whom ventricular fibrillation was induced, and 98%, 96%, 94%, 94% for patients with induced sustained monomorphic ventricular tachycardia. Where there was no sustained arrhythmia, five year survival was 100%. CONCLUSIONS--In patients receiving amiodarone because of life threatening ventricular arrhythmias after myocardial infarction, inducibility of ventricular fibrillation, but not of sustained monomorphic ventricular tachycardia, indicates a high risk of sudden death. PMID:8624866

  7. Tracking preference as unusual trigger of pacemaker-mediated tachycardia in a resynchronization device.

    PubMed

    Crea, Pasquale; Picciolo, Giuseppe; Luzza, Francesco

    2016-01-01

    A 59-year-old woman with a history of congestive heart failure, who previously received a biventricular cardioverter-defibrillator was admitted with dyspnea and peripheral edema. She was noted on telemetry to have multiple self-terminated episodes of rapid ventricular pacing, consistent with pacemaker-mediated tachycardia. All episodes started after three consecutive ventricular extrasystoles. "Tracking preference" algorithm, designed to maintain atrial-tracked biventricular pacing in CRT devices, resulted turned on. It affected minimum PVARP and resulted the trigger for pacemaker mediated tachycardia. PMID:26976512

  8. Rate-related accelerating (autodecremental) atrial pacing for reversion of paroxysmal supraventricular tachycardia.

    PubMed

    Nathan, A; Hellestrand, K; Ward, D; Spurrell, R; Camm, J

    1982-01-01

    Twenty consecutive patients with paroxysmal intra A-V nodal or atrio-ventricular tachycardia had a new tachycardia reversion pacing modality evaluated during routine electrophysiological study. The pacing was controlled by a micropressor interfaced with a stimulator connected to a right atrial pacing electrode. On detection of tachycardia the first pacing cycle interval is equal to the tachycardia cycle length minus a decrement value D. Each subsequent pacing cycle is further reduced by the same value of D, thus accelerating the pacing burst until a plateau of 100 beats/min faster than tachycardia (with an absolute lower limit of 275 beats/min) is reached. Seven different values of D (2, 4, 8, 16, 24, 34, 50 msec) were assessed in combination with three different durations of pacing P (500, 5000 msec). With P:500, only 2/20 tachycardias were terminated, but with P:1000, 16/20 were terminated. With P:5000 all were terminated and the combination successful in all patients was P:5000 and D:16. No unwanted arrhythmias were induced. In contrast, competitive constant rate overdrive atrial pacing accomplished tachycardia termination in all cases, but in four instances resulted in atrial flutter or fibrillation. Autodecremental pacing, which tends to avoid stimulation in the vulnerable period, allowed safe and successful termination of all tachycardias evaluated in this study. PMID:7069321

  9. [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

  10. A two-phase fluid volume compensation chamber for an electric ventricular assist device.

    PubMed

    Lamson, T C; Ojan, O S; Geselowitz, D B; Tarbell, J M

    1990-08-01

    A volume compensation chamber is a device used to reduce large pressure fluctuations created in electric ventricular assist devices during the emptying and filling of the blood sac. In this study, the effect of motor casing pressure variation (pressure swing) on the performance of the Penn State electric ventricular assist device (EVAD) was investigated. Design criteria were established for the maximum pressure swing tolerated by the EVAD and the optimal mean chamber pressure at which to operate. At the chosen mean chamber pressure of -15 mm Hg, it was found that pressure swing should be maintained below 45 mm Hg. A two-phase fluid volume compensation chamber was developed that reduced the pressure swing enough to ensure adequate pump performance. The device consists of a metal chamber with a high-heat-flux porous coating applied to the inside surface. The chamber uses Freon as the working fluid and is isolated from the EVAD by a metal bellows. It was found that the high-flux coating significantly reduces the pressure swing, in some cases by as much as 50% when compared with an identical chamber with no coating. In the coated chamber the pressure swing was maintained between 22 and 30 mm Hg at a beat rate of 60 beats/min, for a wide range of Freon volumes (4-38 ml). Even at 100 beats/min the pressure swings obtained with the coated chamber are well within an acceptable range. PMID:2396924

  11. Is ventricular ectopy a legitimate target for ablation?

    PubMed Central

    Gumbrielle, T; Bourke, J P; Furniss, S S

    1994-01-01

    Radiofrequency ablation has an established role in the treatment of non-ischaemic ventricular tachycardia. A few patients present with symptomatic but benign ventricular ectopy that can be mapped to the right ventricular outflow tract. The successful use of radiofrequency ablation in a patient with drug resistant, symptomatic ventricular ectopy is reported. Radiofrequency ablation may have a useful role in more benign arrhythmias. PMID:7818971

  12. Electrical injury causing ventricular arrhythmias.

    PubMed Central

    Jensen, P J; Thomsen, P E; Bagger, J P; Nørgaard, A; Baandrup, U

    1987-01-01

    Dangerous or long lasting ventricular arrhythmias developed in three patients who had sustained an electrical injury in which current passed through the thorax. In all three cases there was a delay of 8-12 hours between the injury and the onset of symptoms. The ventricular arrhythmias were severe and long lasting. In two of the three patients, ventricular tachycardia or ventricular fibrillation or both occurred and in one patient ventricular parasystole developed. No enzymatic evidence of myocardial necrosis was found but the results of an endomyocardial biopsy carried out in two of the three patients showed focal myocardial fibrosis and increased numbers of Na, K-pumps. The two patients with ventricular tachycardia became symptom free after appropriate antiarrhythmic treatment and in the third patient ventricular parasystole disappeared spontaneously within two years. Patients sustaining electrical injury in which current passes through the thorax should be monitored electrocardiographically for at least 24 hours, and patients with unexpected arrhythmias should be questioned about previous electrical injury. Images Fig 2 PMID:3566986

  13. Phase Relationship between Alternans of Early and Late Phases of Ventricular Action Potentials

    PubMed Central

    Jing, Linyuan; Agarwal, Anuj; Chourasia, Sonam; Patwardhan, Abhijit

    2012-01-01

    Background: Alternans of early phase and of duration of action potential (AP) critically affect dispersion of refractoriness through their influence on conduction and repolarization. We investigated the phase relationship between the two alternans and its effect on conduction. Methods and Results: Transmembrane potentials recorded from ventricles of eight swine and three canines during paced activation intervals of ≤300 ms were used to quantify alternans of maximum rate of depolarization (|dv/dt|max) and of action potential duration (APD). Incidence of APD alternans was 62 and 76% in swine and canines. Alternans of APD was frequently accompanied with alternans of |dv/dt|max. Of these, 4 and 26% were out of phase in swine and canines, i.e., low |dv/dt|max preceded long APD. Computer simulations show that out of phase alternans attenuate variation of wavelength and thus minimize formation of spatially discordant alternans. Conclusion: The spontaneous switching of phase relationship between alternans of depolarization and repolarization suggests that mechanisms underlying these alternans may operate independent of each other. The phase between these alternans can critically impact spatial dispersion of refractoriness and thus stability of conduction, with the in phase relation promoting transition from concord to discord while out of phase preventing formation of discord. PMID:22701104

  14. Radiofrequency catheter ablation of Mahaim tachycardia by targeting Mahaim potentials at the tricuspid annulus.

    PubMed Central

    Heald, S. C.; Davies, D. W.; Ward, D. E.; Garratt, C. J.; Rowland, E.

    1995-01-01

    BACKGROUND--Reentrant tachycardias associated with Mahaim pathways are rare but potentially troublesome. Various electrophysiological substrates have been postulated and catheter ablation at several sites has been described. OBJECTIVE--To assess the efficacy and feasibility of targeting discrete Mahaim potentials recorded on the tricuspid annulus for the delivery of radiofrequency energy in the treatment of Mahaim tachycardia. PATIENTS--21 patients out of a consecutive series of 579 patients referred to one of three tertiary centres for catheter ablation of accessory pathways causing tachycardia. All had symptoms and presented with tachycardia of left bundle branch block configuration or had this induced at electrophysiological study. In all cases, the tachycardia was antidromic with anterograde conduction over a Mahaim pathway. RESULTS--6 patients had additional tachycardia substrates (4 had accessory atrioventricular connections and 2 had dual atrioventricular nodal pathways and atrioventricular nodal reentry). After ablation of the additional pathways, Mahaim potentials were identified in 16 (76%) associated with early activation of the distal right bundle branch and radiofrequency energy at this site on the tricuspid annulus abolished Mahaim conduction in all 16 cases. In 2 patients there was early ventricular activation at the annulus without a Mahaim potential but radiofrequency energy abolished pre-excitation. In the remaining patients no potential could be found (1 patient), no tachycardia could be induced after ablation of an additional pathway (1 patient), or no Mahaim conduction was evident during the study (1 patient). During follow up (1-29 months (median 9 months)) all but 1 patient remained symptom free without medication. CONCLUSIONS--Additional accessory pathways seem to be common in patients with Mahaim tachycardias. The identification of Mahaim potentials at the tricuspid annulus confirms that most of these pathways are in the right free wall and

  15. Conventional management of inappropriate sinus tachycardia.

    PubMed

    Olshansky, Brian; Sullivan, Renee M

    2016-06-01

    Inappropriate sinus tachycardia is a challenging problem to manage. There are limited data on the best method to evaluate and treat the problem. Here, we consider a conventional approach to inappropriate sinus tachycardia. PMID:26164138

  16. Diurnal Variability in Orthostatic Tachycardia: Implications for Postural Tachycardia Syndrome

    PubMed Central

    Brewster, Jordan A; Garland, Emily M.; Biaggioni, Italo; Black, Bonnie K; Ling, John F; Shibao, Cyndya A; Robertson, David; Raj, Satish R

    2011-01-01

    Patients with Postural Tachycardia Syndrome (POTS) have excessive orthostatic tachycardia (>30 bpm) when standing from a supine position. Heart rate (HR) and blood pressure (BP) are known to exhibit diurnal variability, but the role of diurnal variability in orthostatic changes of HR & BP is not known. In this study, we tested the hypothesis that there is diurnal variation of orthostatic HR & BP in patients with POTS and healthy controls. Patients with POTS (n=54) and healthy volunteers (n=26) were admitted to the Clinical Research Center. Supine and standing (5 min) HR & BP were obtained on the evening on the day of admission and in the following morning. Overall, standing HR was significantly higher in the morning than the evening (102±3 bpm [AM] vs. 93±2 bpm [PM]; P<0.001). Standing HR was higher in the morning in both POTS patients (108±4 bpm [AM] vs. 100±3 bpm [PM]; P=0.012) and controls (89±3 bpm [AM] vs. 80±2 bpm [PM]; P=0.005), when analyzed separately. There was no diurnal variability in orthostatic BP in POTS. More subjects met the POTS HR criterion in the morning compared with the evening (P=0.008). There was significant diurnal variability in orthostatic tachycardia, with a great orthostatic tachycardia in the morning compared to the evening in both patients with POTS and healthy subjects. Given the importance of orthostatic tachycardia in diagnosing POTS, this diurnal variability should be considered in the clinic as it may affect the diagnosis of POTS. PMID:21751966

  17. Stochastic dynamics of phase singularities under ventricular fibrillation in 2D Beeler-Reuter model

    NASA Astrophysics Data System (ADS)

    Suzuki, Akio; Konno, Hidetoshi

    2011-09-01

    The dynamics of ventricular fibrillation (VF) has been studied extensively, and the initiation mechanism of VF has been elucidated to some extent. However, the stochastic dynamical nature of sustained VF remains unclear so far due to the complexity of high dimensional chaos in a heterogeneous system. In this paper, various statistical mechanical properties of sustained VF are studied numerically in 2D Beeler-Reuter-Drouhard-Roberge (BRDR) model with normal and modified ionic current conductance. The nature of sustained VF is analyzed by measuring various fluctuations of spatial phase singularity (PS) such as velocity, lifetime, the rates of birth and death. It is found that the probability density function (pdf) for lifetime of PSs is independent of system size. It is also found that the hyper-Gamma distribution serves as a universal pdf for the counting number of PSs for various system sizes and various parameters of our model tissue under VF. Further, it is demonstrated that the nonlinear Langevin equation associated with a hyper-Gamma process can mimic the pdf and temporal variation of the number of PSs in the 2D BRDR model.

  18. Relationship between myocardial flow reserve by oxygen-15 water positron emission tomography in the subacute phase of myocardial infarction and left ventricular remodeling in the chronic phase.

    PubMed

    Ohara, Minako; Yukiiri, Kazushi; Masugata, Hisashi; Iwado, Yasuyoshi; Takinami, Hiroyuki; Nishiyama, Yoshihiro; Ohkawa, Motoomi; Senda, Shoichi; Ohmori, Koji; Kohno, Masakazu

    2008-07-01

    The purposes of this study were to examine the effects of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) on myocardial flow reserve in patients with acute myocardial infarction (AMI) in the subacute phase using oxygen-15 positron emission tomography (PET) and to elucidate the relationship between the myocardial flow reserve and remodeling in the chronic phase. Sixty patients who had been treated with coronary angioplasty within 12 h after the onset of AMI were enrolled. Patients were divided into an enalapril (ACEI) group and a candesartan (ARB) group. The myocardial flow reserve was measured by oxygen-15 water PET in the subacute phase from the 20th to the 30th day after the onset of AMI. Left ventriculography was performed to measure the left ventricular ejection fraction in the chronic phase about 6 months after the onset. Ten patients (33%) in the enalapril group and 4 patients (13%) in the candesartan group stopped taking their respective medications within a few days of starting, because of side effects such as cough or hypotension. Thus, the prevalence of medication intolerance was higher in the enalapril group. The myocardial flow reserve in the subacute phase and the left ventricular ejection fraction in the chronic phase were lower in the enalapril group (2.08 +/- 0.30 and 42 +/- 6%) than in the candesartan group (2.25 +/- 0.20 and 49 +/- 5%) (p < 0.05). The myocardial flow reserve significantly correlated with the left ventricular ejection fraction in all patients (r = 0.45, p < 0.01). The myocardial flow reserve assessed by PET in the subacute phase after AMI was found to be related to left ventricular remodeling in the chronic phase. PMID:18957800

  19. Concomitant Wolff-Parkinson-White and Atrioventricular Nodal Reentrant Tachycardia: Which Pathway to Ablate?

    PubMed Central

    Sarsam, Sinan; Sidiqi, Ibrahim; Shah, Dipak; Zughaib, Marcel

    2015-01-01

    Patient: Male, 54 Final Diagnosis: WPW and AVNRT Symptoms: Palpitations • shorthness of breath Medication: — Clinical Procedure: EP Study/Radiofrequency Ablation Specialty: Cardiology Objective: Rare co-existance of disease or pathology Background: Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common form of supraventricular tachycardia. In contrast, Wolff-Parkinson-White (WPW) pattern consists of an accessory pathway, which may result in the development of ventricular arrhythmias. Frequent tachycardia caused by AVNRT and accessory pathways may play a role in left ventricular systolic dysfunction. Case Report: A 54-year-old man presented with palpitations and acute decompensated congestive heart failure. His baseline EKG showed Wolff-Parkinson-White (WPW) pattern. While hospitalized, he had an episode of atrioventricular nodal reentrant tachycardia (AVNRT). He underwent radiofrequency catheter ablation for AVNRT, and his accessory pathway was also ablated even though its conduction was found to be weak. He was clinically doing well on follow-up visit, with resolution of his heart failure symptoms and normalization of left ventricular function on echocardiography. Conclusions: This case raises the question whether the accessory pathway plays a role in the development of systolic dysfunction, and if there is any role for ablation in patients with asymptomatic WPW pattern. PMID:26655223

  20. Electrophysiological actions of somatostatin on the atrioventricular junction in sinus rhythm and reentry tachycardia.

    PubMed Central

    Webb, S C; Krikler, D M; Hendry, W G; Adrian, T E; Bloom, S R

    1986-01-01

    Because somatostatin, a neuroregulatory peptide, is found in abundance in the atria and atrioventricular node, its electrophysiological and antiarrhythmic properties were compared with those of verapamil in ten patients with paroxysmal atrioventricular tachycardia. During sinus rhythm, intravenous somatostatin slowed the heart rate whereas verapamil increased it. Though both agents prolonged atrioventricular conduction time and refractoriness, verapamil was more potent. They were equally effective at terminating reentry atrioventricular tachycardia, restoring sinus rhythm in six of seven patients. Whereas verapamil consistently blocked conduction in the atrioventricular node, somatostatin usually induced ventricular extrasystoles at the time of conversion. Somatostatin may have physiological importance in the neurohumoral control of cardiac impulse formation and conduction. PMID:2875723

  1. Optimal left ventricular lead position assessed with phase analysis on gated myocardial perfusion SPECT

    PubMed Central

    Boogers, Mark J.; Chen, Ji; van Bommel, Rutger J.; Borleffs, C. Jan Willem; Dibbets-Schneider, Petra; van der Hiel, Bernies; Al Younis, Imad; Schalij, Martin J.; van der Wall, Ernst E.; Garcia, Ernest V.

    2010-01-01

    Purpose The aim of the current study was to evaluate the relationship between the site of latest mechanical activation as assessed with gated myocardial perfusion SPECT (GMPS), left ventricular (LV) lead position and response to cardiac resynchronization therapy (CRT). Methods The patient population consisted of consecutive patients with advanced heart failure in whom CRT was currently indicated. Before implantation, 2-D echocardiography and GMPS were performed. The echocardiography was performed to assess LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). The site of latest mechanical activation was assessed by phase analysis of GMPS studies and related to LV lead position on fluoroscopy. Echocardiography was repeated after 6 months of CRT. CRT response was defined as a decrease of ≥15% in LVESV. Results Enrolled in the study were 90 patients (72% men, 67±10 years) with advanced heart failure. In 52 patients (58%), the LV lead was positioned at the site of latest mechanical activation (concordant), and in 38 patients (42%) the LV lead was positioned outside the site of latest mechanical activation (discordant). CRT response was significantly more often documented in patients with a concordant LV lead position than in patients with a discordant LV lead position (79% vs. 26%, p<0.01). After 6 months, patients with a concordant LV lead position showed significant improvement in LVEF, LVESV and LVEDV (p<0.05), whereas patients with a discordant LV lead position showed no significant improvement in these variables. Conclusion Patients with a concordant LV lead position showed significant improvement in LV volumes and LV systolic function, whereas patients with a discordant LV lead position showed no significant improvements. PMID:20953608

  2. [Hypertrophic cardiomyopathy with mid-ventricular obstruction complicated by apical aneurysm appearing as delayed contrast hyperenhancement on magnetic resonance imaging: two case reports].

    PubMed

    Teraoka, Kunihiko; Hirano, Masaharu; Ogawa, Takashi; Sasame, Atsuko; Yanagisawa, Hidefumi; Namatame, Yasuhide; Shindo, Naohisa; Takei, Yasuyoshi; Sasaki, Kazuyoshi; Katsuyama, Hiroaki; Abe, Kimihiko; Yamashina, Akira

    2003-08-01

    Case 1: A 52-year-old man presented with a chief complaint of palpitation. Diabetes mellitus was pointed out in 1992. Electrocardiography (ECG) revealed left ventricular hypertrophy in 1997. He visited our department in October 1997. Echocardiography showed increased wall thickness at the interventricular septum. The diagnosis was hypertrophic cardiomyopathy. Holter ECG revealed nonsustained ventricular tachycardia in December 1997. After this, he visited our outpatient clinic. Echocardiography indicated ventricular aneurysm in January 2002, so he was hospitalized in March 2002. Case 2: A 64-year-old woman was transferred to our hospital because of chest discomfort and tachycardial attack. She had been treated for hypertension and diabetes mellitus. She was taken to a hospital by ambulance. On admission, ECG showed wide QRS tachycardia. Cardiac magnetic resonance imaging in both patients disclosed almost complete obstruction of the mid-ventricle in the systolic phase on long- and short-axis cine images, and gadolinium delayed imaging revealed contrast hyperenhancement corresponding to an apical ventricular aneurysm on both long- and short-axis images. The final diagnosis was mid-ventricular obstructive hypertrophic cardiomyopathy with apical aneurysm characterized by delayed hyperenhancement on magnetic resonance imaging with gadolinium. PMID:12964519

  3. Successful electrical cardioversion of supraventricular tachycardia in a pregnant patient

    PubMed Central

    Yılmaz, Fevzi; Beydilli, Inan; Kavalcı, Cemil; Yılmaz, Serkan

    2012-01-01

    Summary Background: Pregnancy can precipitate cardiac arrhythmias not previously present in seemingly well individuals. Atrial and ventricular premature beats are frequently present during pregnancy and are usually benign. Supraventricular tachycardia and malignant ventricular tachyarrhythmias occur less frequently. Maternal and fetal arrhythmias occurring during pregnancy may jeopardize the life of the mother and the fetus. Case Report: A 32-year-old pregnant women at 26 weeks gestation presented to the emergency department with palpitation. She had mild chest discomfort after a supraventricular tachycardia (SVT) episode but did not have syncope. After monitoring and access of an IV line, vagal manoeuvres were applied but the rhythm was resistant. Then she was treated with 5 mg metoprolol IV, but the SVT persisted. Then after IV infusion of adenosine triphosphate 6 to 12 mg, the rhythm was resistant. Synchronized cardioversion with 100 joules was performed. Patients’ rhythm was normalized to a sinus rhythm. She was discharged from hospital without any adverse effects following 24-hour monitoring. Conclusions: All pregnant patients with SVT require careful maternal and fetal monitoring during treatment, and close collaboration between the managing obstetrician and the cardiologist is essential. PMID:23569481

  4. Torsade de pointes tachycardia in a patient on dronedarone therapy.

    PubMed

    Huemer, Martin; Sarganas, Giselle; Bronder, Elisabeth; Klimpel, Andreas; Garbe, Edeltraut; Haverkamp, Wilhelm

    2015-05-01

    Dronedarone is a promising, relatively new antiarrhythmic agent characterized by structural similarities to amiodarone but without amiodarone's severe organ toxicity. The proarrhythmic potential of dronedarone, however, is of increasing concern. We describe a 76-year-old woman who had been receiving dronedarone 400 mg twice/day to prevent recurrent atrial tachycardia with rapid ventricular response. Several months later, she came to the emergency department with decompensated congestive heart failure and episodes of atrial tachycardia; digoxin 0.5 mg and furosemide 40 mg were administered intravenously. Thereafter nonsustained torsade de pointes (TdP) tachycardia occurred. She was transferred to the intensive care unit where a dose of amiodarone 150 mg was administered intravenously by mistake. Thereafter, the patient showed sustained TdP necessitating cardiac resuscitation. Dronedarone was discontinued, and digoxin and amiodarone were not administered again. Under dronedarone a relevant QT prolongation was documented that was additionally augmented after concomitant treatment with digoxin and amiodarone. Use of the Naranjo adverse drug reaction probability scale indicated a probable adverse drug reaction to dronedarone (score of 7). To our knowledge, this is the first case report of a patient who experienced TdP tachycardias while receiving dronedarone therapy in connection with a worsening of heart failure and possible drug interactions with digoxin and amiodarone. Clinicians should be aware of this potential adverse drug reaction and perform repeated heart rate-corrected QT (QTc) interval measurements as well as screening for congestive heart failure in patients receiving dronedarone therapy. PMID:25823967

  5. Postural orthostatic tachycardia syndrome (POTS)

    PubMed Central

    Sidhu, Bharat; Obiechina, Nonyelum; Rattu, Noman; Mitra, Shanta

    2013-01-01

    Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous group of conditions characterised by autonomic dysfunction and an exaggerated sympathetic response to assuming an upright position. Up till recently, it was largely under-recognised as a clinical entity. There is now consensus about the definition of POTS as a greater than 30/min heart rate increase on standing from a supine position (greater than 40/min increase in 12–19-year-old patients) or an absolute heart rate of greater than 120/min within 10 min of standing from a supine position and in the absence of hypotension, arrhythmias, sympathomimetic drugs or other conditions that cause tachycardia. We present two cases of POTS, followed by a discussion of its pathogenesis, pathophysiology, epidemiology and management. PMID:24042210

  6. Relationship of number of phases per cardiac cycle and accuracy of measurement of left ventricular volumes, ejection fraction, and mass.

    PubMed

    Roussakis, Arkadios; Baras, Panagiotis; Seimenis, Ioannis; Andreou, John; Danias, Peter G

    2004-01-01

    In cine cardiac magnetic resonance imaging (MRI) studies, for any preset imaging parameters the number of phases per cardiac cycle for a single slice is proportional to breath-hold duration. We investigated the relationship between the accuracy of measurement of left ventricular (LV) end-diastolic and end-systolic volumes (EDV and ESV, respectively), mass and ejection fraction (EF), and the number of phases acquired per cardiac cycle. Twelve adult volunteers underwent cardiac MRI and five complete LV functional studies were obtained with 8, 11, 14, 17, and 20 phases per cardiac cycle. We calculated LV volumes, EF, and mass for each acquisition, and compared them using the 20-phase acquisition as the reference standard. The scan duration was proportional to the number of phases acquired. There was a systematic underestimation of LV, EDV, and EF, with decreasing number of phases. Differences from the reference standard became significant for the 8-phase acquisition (p<0.05). Subgroup analysis showed that only those with slower heart rates (<65/min) had significant differences in EDV, but not in EF, for the 8-phase acquisition. For those with faster heart rates, no differences were detected between the different acquisitions. There were no significant differences between all acquisitions for the LV ESV and mass. We conclude that at least 11 phases per cardiac cycle are needed to maintain accuracy for cine cardiac MRI studies. Decreasing the number of phases per cardiac cycle beyond this cutoff may introduce significant error of measurement, particularly for the left ventricular EDV and EF and especially for those with bradycardia, and should be avoided. PMID:15646887

  7. The neuropathic postural tachycardia syndrome

    NASA Technical Reports Server (NTRS)

    Jacob, G.; Costa, F.; Shannon, J. R.; Robertson, R. M.; Wathen, M.; Stein, M.; Biaggioni, I.; Ertl, A.; Black, B.; Robertson, D.

    2000-01-01

    BACKGROUND: The postural tachycardia syndrome is a common disorder that is characterized by chronic orthostatic symptoms and a dramatic increase in heart rate on standing, but that does not involve orthostatic hypotension. Several lines of evidence indicate that this disorder may result from sympathetic denervation of the legs. METHODS: We measured norepinephrine spillover (the rate of entry of norepinephrine into the venous circulation) in the arms and legs both before and in response to exposure to three stimuli (the cold pressor test, sodium nitroprusside infusion, and tyramine infusion) in 10 patients with the postural tachycardia syndrome and in 8 age- and sex-matched normal subjects. RESULTS: At base line, the mean (+/-SD) plasma norepinephrine concentration in the femoral vein was lower in the patients with the postural tachycardia syndrome than in the normal subjects (135+/-30 vs. 215+/-55 pg per milliliter [0.80+/-0.18 vs. 1.27+/-0.32 nmol per liter], P=0.001). Norepinephrine spillover in the arms increased to a similar extent in the two groups in response to each of the three stimuli, but the increases in the legs were smaller in the patients with the postural tachycardia syndrome than in the normal subjects (0.001+/-0.09 vs. 0.12+/-0.12 ng per minute per deciliter of tissue [0.006+/-0.53 vs. 0.71+/-0.71 nmol per minute per deciliter] with the cold pressor test, P=0.02; 0.02+/-0.07 vs. 0.23+/-0.17 ng per minute per deciliter [0.12+/-0.41 vs. 1.36+/-1.00 nmol per minute per deciliter] with nitroprusside infusion, P=0.01; and 0.008+/-0.09 vs. 0.19+/-0.25 ng per minute per deciliter [0.05+/-0.53 vs. 1.12+/-1.47 nmol per minute per deciliter] with tyramine infusion, P=0.04). CONCLUSIONS: The neuropathic postural tachycardia syndrome results from partial sympathetic denervation, especially in the legs.

  8. Assessment, significance and mechanism of ventricular electrical instability after myocardial infarction.

    PubMed

    Richards, David A B; Denniss, A Robert

    2007-06-01

    The mechanism of reentrant tachycardia was established nearly a century ago, but the relationships between myocardial infarction and predisposition to sudden death were not unravelled until much later. In the latter half of the twentieth century many studies sought to ascertain what variables were predictive of death following myocardial infarction. Approximately one half of all deaths during the year following myocardial infarction are sudden and due to ventricular tachycardia (VT) or ventricular fibrillation (VF). We aimed to utilise non-invasive signal-averaging, along with programmed electrical stimulation of the heart, to determine whether one could predict spontaneous ventricular tachycardia and sudden death late after myocardial infarction. The sensitivity of ventricular electrical instablility (inducible ventricular tachycardia or fibrillation) as a predictor of instantaneous death or spontaneous VT was 86%, and the specificity was 83%. When other variables (delayed ventricular activation at signal-averaging, ejection fraction at gated heart pool scan, ventricular ectopic activity at ambulatory monitoring and exercise testing) were taken into account, inducible VT at electrophysiological study was the single best predictor of spontaneous VT and sudden cardiac death after myocardial infarction. The Westmead studies of Uther et al. in the decade or so from 1980 established programmed stimulation as the best predictor of sudden death after myocardial infarction. Subsequent studies by others have demonstrated a survival advantage of defibrillator implantation in patients with low ejection fraction (and inducible ventricular tachycardia) after myocardial infarction. PMID:17446130

  9. Evaluation of mechanical dyssynchrony and myocardial perfusion using phase analysis of gated SPECT imaging in patients with left ventricular dysfunction

    PubMed Central

    Trimble, Mark A.; Borges-Neto, Salvador; Honeycutt, Emily F.; Shaw, Linda K.; Pagnanelli, Robert; Chen, Ji; Iskandrian, Ami E.; Garcia, Ernest V.; Velazquez, Eric J.

    2010-01-01

    Background Using phase analysis of gated single photon emission computed tomography (SPECT) imaging, we examined the relation between myocardial perfusion, degree of electrical dyssynchrony, and degree of SPECT-derived mechanical dyssynchrony in patients with left ventricular (LV) dysfunction. Methods and Results We retrospectively examined 125 patients with LV dysfunction and ejection fraction of 35% or lower. Fourier analysis converts regional myocardial counts into a continuous thickening function, allowing resolution of phase of onset of myocardial thickening. The SD of LV phase distribution (phase SD) and histogram bandwidth describe LV phase dispersion as a measure of dyssynchrony. Heart failure (HF) patients with perfusion abnormalities ities have higher degrees of dyssynchrony measured by median phase SD (45.5° vs 27.7°, P < .0001) and bandwidth (117.0° vs 73.0°, P = .0006). HF patients with prolonged QRS durations have higher degrees of dyssynchrony measured by median phase SD (54.1° vs 34.7°, P < .0001) and bandwidth (136.5° vs 99.0°, P = .0005). Mild to moderate correlations exist between QRS duration and phase analysis indices of phase SD (r = 0.50) and bandwidth (r = 0.40). Mechanical dyssynchrony (phase SD >43°) was 43.2%. Conclusions HF patients with perfusion abnormalities or prolonged QRS durations QRS durations have higher degrees of mechanical dyssynchrony. Gated SPECT myocardial perfusion imaging can quantify myocardial function, perfusion, and dyssynchrony and may help in evaluating patients for cardiac resynchronization therapy. PMID:18761269

  10. Incessant Palpitations and Narrow Complex Tachycardia.

    PubMed

    Han, Frederick T

    2016-03-01

    Junctional tachycardia (JT) is rare cause of supraventricular tachycardia. The intracardiac activation sequence is similar to atrioventricular nodal reentrant tachycardia (AVNRT). Premature atrial contractions inserted during tachycardia can help distinguish JT from AVNRT. As noted in this case, slow pathway ablation for JT may not always be effective for termination of JT. Activation mapping during JT identified a low-amplitude potential in the region of the coronary sinus ostium and the inferior margin of the triangle of Koch that marked the successful ablation site for JT. PMID:26920171

  11. [Liquorice consumption may induce torsades de pointes ventricular tachycardia].

    PubMed

    Smith, Mette Aaby; Pedersen, Charlotte; Henriksen, Finn Lund

    2016-07-11

    This case report describes an often forgotten cause of hypokalaemia resulting in electrocardiograpic changes in a 75-year-old man known with hypertension, atrial fibrillation and ischaemic heart disease. A detailed anamnesis, a prompt replacement of potassium and cessation of liquorice consumption resulted in a favourable outcome. PMID:27406286

  12. Reversible cardiomyopathy after radiofrequency ablation of 30-year persistent atrial tachycardia

    PubMed Central

    Suzuki, Atsushi; Shiga, Tsuyoshi; Arai, Kotaro; Shoda, Morio

    2013-01-01

    Tachycardia-induced cardiomyopathy (TIC) is a reversible form of the left ventricular (LV) systolic dysfunction and is believed to be a relatively acute process. We report a TIC case with a 30-year history of long-lasting persistent atrial tachycardia involving a 44-year-old man previously diagnosed with dilated cardiomyopathy and a low LV ejection fraction (LVEF) of 20%. ECG revealed atrial tachycardia at 110–120 bpm. He was hospitalised with a worsening heart failure. His clinical status was New York Heart Association functional class III, and echocardiography revealed LV dilation and an LVEF of 9%. A two-dimensional speckle-tracking strain measurement revealed LV mechanical dyssynchrony. He underwent radiofrequency ablation for atrial tachycardia. After restoring sinus rhythm, his cardiac symptoms improved immediately. The LV mechanical dyssynchrony decreased a week after ablation, without changes in the LV dilation or LVEF. Thereafter, the LV dilation and systolic function gradually improved, and atrial tachycardia and heart failure remained absent. PMID:24326427

  13. Fluid-structure coupled CFD simulation of the left ventricular flow during filling phase.

    PubMed

    Cheng, Yongguang; Oertel, Herbert; Schenkel, Torsten

    2005-05-01

    The fluid-structure coupled simulation of the heart, though at its developing stage, has shown great prospect in heart function investigations and clinical applications. The purpose of this paper is to verify a commercial software based fluid-structure interaction scheme for the left ventricular filling. The scheme applies the finite volume method to discretize the arbitrary Lagrangian-Eulerian formulation of the Navier-Stokes equations for the fluid while using the nonlinear finite element method to model the structure. The coupling of the fluid and structure is implemented by combining the fluid and structure equations as a unified system and solving it simultaneously at every time step. The left ventricular filling flow in a three-dimensional ellipsoidal thin-wall model geometry of the human heart is simulated, based on a prescribed time-varying Young's modulus. The coupling converges smoothly though the deformation is very large. The pressure-volume relation of the model ventricle, the spatial and temporal distributions of pressure, transient velocity vectors as well as vortex patterns are analyzed, and they agree qualitatively and quantitatively well with the existing data. This preliminary study has verified the feasibility of the scheme and shown the possibility to simulate the left ventricular flow in a more realistic way by adding a myocardial constitutive law into the model and using a more realistic heart geometry. PMID:15981858

  14. Landiolol for junctional ectopic tachycardia refractory to amiodarone after pediatric cardiac surgery.

    PubMed

    Hasegawa, Tomomi; Oshima, Yoshihiro; Maruo, Ayako; Matsuhisa, Hironori; Kadowaki, Tasuku; Noda, Rei

    2013-06-01

    Postoperative junctional ectopic tachycardia (JET) in children undergoing cardiac surgery is a serious arrhythmia that is associated with considerable morbidity and mortality. We present here a case of successful landiolol therapy for postoperative JET in a 3-month-old infant who underwent ventricular septal defect closure and right pulmonary artery plasty. His left ventricular function was poor postoperatively. The JET was refractory to amiodarone and caused severe hypotension, which was required cardiac massage. Continuous intravenous infusion of low-dose landiolol reduced the persistent JET rate immediately, and restored to sinus rhythm with stable hemodynamics. PMID:22893321

  15. Postural tachycardia syndrome: time frequency mapping.

    PubMed

    Novak, V; Novak, P; Opfer-Gehrking, T L; Low, P A

    1996-12-14

    Orthostatic tachycardia is common but its specificity remains uncertain. Our preliminary work suggested that using autonomic function testing in conjunction with time-frequency mapping (TFM), it might be possible to characterize a subset of the postural tachycardia syndrome (POTS), that is due to a restricted autonomic neuropathy. We describe 20 patients (17 women and 3 men, aged 14-43 years) with florid POTS and 20 controls (14 women and 6 men, aged 20-41 years). Autonomic failure was quantified by its distribution (cardiovagal, adrenergic and sudomotor) and severity, a symptom profile was generated, and spectral indices, based on modified Wigner distribution during rest and head-up tilt (80 degrees) were evaluated. During tilt-up POTS patients differed from controls by an excessive heart rate (> 130 bpm) (P < 0.001), and higher diastolic pressure (P < 0.01). During rest, cardiovagal oscillations (at respiratory frequencies [RF]) and slow rhythms at nonrespiratory frequencies (NONRF) (from 0.01 to 0.07 Hz) in R-R intervals (RRI) (P < 0.01) were reduced. Both RF and NONRF rhythms in RRI were further blunted with tilt-up (P < 0.001). Slow adrenergic vasomotor rhythms in blood pressure (BP) (approximately 0.07 Hz) surged with tilt-up and returned to normal levels afterwards. The index of sympatho-vagal balance (NONRF-Systolic BP (SBP)/RF-RRI) was dramatically increased in POTS (P < 0.001). Distal postganglionic sudomotor failure was observed, and impairment of the BP responses to the Valsalva maneuver (phase II) suggested peripheral adrenergic dysfunction. Persistent orthostatic dizziness, tiredness, gastrointestinal symptoms and palpitations were common in POTS patients. It is possible to identify a subset of POTS patients who have a length-dependent autonomic neuropathy, affecting the peripheral adrenergic and cardiovagal fibers, with relative preservation of cardiac adrenergic fibers. PMID:8988490

  16. Postural tachycardia syndrome: time frequency mapping

    NASA Technical Reports Server (NTRS)

    Novak, V.; Novak, P.; Opfer-Gehrking, T. L.; Low, P. A.

    1996-01-01

    Orthostatic tachycardia is common but its specificity remains uncertain. Our preliminary work suggested that using autonomic function testing in conjunction with time-frequency mapping (TFM), it might be possible to characterize a subset of the postural tachycardia syndrome (POTS), that is due to a restricted autonomic neuropathy. We describe 20 patients (17 women and 3 men, aged 14-43 years) with florid POTS and 20 controls (14 women and 6 men, aged 20-41 years). Autonomic failure was quantified by its distribution (cardiovagal, adrenergic and sudomotor) and severity, a symptom profile was generated, and spectral indices, based on modified Wigner distribution during rest and head-up tilt (80 degrees) were evaluated. During tilt-up POTS patients differed from controls by an excessive heart rate (> 130 bpm) (P < 0.001), and higher diastolic pressure (P < 0.01). During rest, cardiovagal oscillations (at respiratory frequencies [RF]) and slow rhythms at nonrespiratory frequencies (NONRF) (from 0.01 to 0.07 Hz) in R-R intervals (RRI) (P < 0.01) were reduced. Both RF and NONRF rhythms in RRI were further blunted with tilt-up (P < 0.001). Slow adrenergic vasomotor rhythms in blood pressure (BP) (approximately 0.07 Hz) surged with tilt-up and returned to normal levels afterwards. The index of sympatho-vagal balance (NONRF-Systolic BP (SBP)/RF-RRI) was dramatically increased in POTS (P < 0.001). Distal postganglionic sudomotor failure was observed, and impairment of the BP responses to the Valsalva maneuver (phase II) suggested peripheral adrenergic dysfunction. Persistent orthostatic dizziness, tiredness, gastrointestinal symptoms and palpitations were common in POTS patients. It is possible to identify a subset of POTS patients who have a length-dependent autonomic neuropathy, affecting the peripheral adrenergic and cardiovagal fibers, with relative preservation of cardiac adrenergic fibers.

  17. [Wide QRS tachycardia preceded by pacemaker spikes].

    PubMed

    Romero, M; Aranda, A; Gómez, F J; Jurado, A

    2014-04-01

    The differential diagnosis and therapeutic management of wide QRS tachycardia preceded by pacemaker spike is presented. The pacemaker-mediated tachycardia, tachycardia fibrillo-flutter in patients with pacemakers, and runaway pacemakers, have a similar surface electrocardiogram, but respond to different therapeutic measures. The tachycardia response to the application of a magnet over the pacemaker could help in the differential diagnosis, and in some cases will be therapeutic, as in the case of a tachycardia-mediated pacemaker. Although these conditions are diagnosed and treated in hospitals with catheterization laboratories using the application programmer over the pacemaker, patients presenting in primary care clinic and emergency forced us to make a diagnosis and treat the haemodynamically unstable patient prior to referral. PMID:23768570

  18. Prevalence and predictors of mechanical dyssynchrony as defined by phase analysis in patients with left ventricular dysfunction undergoing gated SPECT myocardial perfusion imaging

    PubMed Central

    Samad, Zainab; Atchley, Allen E.; Trimble, Mark A.; Sun, Jie-Lena; Shaw, Linda K.; Pagnanelli, Robert; Chen, Ji; Garcia, Ernest V.; Iskandrian, Ami E.; Velazquez, Eric J.; Borges-Neto, Salvador

    2011-01-01

    Background A novel method to quantify dyssynchrony using phase analysis of single-photon emission computed tomography (SPECT) myocardial perfusion imaging has been developed. We sought to determine the prevalence of SPECT-derived mechanical dyssynchrony, and we report clinical variables which predict mechanical dyssynchrony in patients with left ventricular dysfunction. Methods We used a count-based Fourier analysis method to convert the regional myocardial counts from discrete frames per cardiac cycle into a continuous thickening function which allows resolution of the phase of the onset of myocardial contraction. The standard deviation of left ventricular phases (Phase SD) describes the regional phase dispersion as a measure of dyssynchrony. Significant dyssynchrony was defined as Phase SD ≥ 43°. 260 patients with left ventricular ejection fraction ≤35% were examined. Results The prevalence of mechanical dyssynchrony in the entire cohort of patients studied was 52%. Univariate predictors of Phase SD were age (P = .03), black race (P = .0005), QRS duration, EF, EDV, summed stress score (SSS), and summed rest score (SRS) (all P = <.0001). Black race, male gender, QRS EF, and SRS were independent predictors of SPECT-based mechanical dyssynchrony. Conclusions Significant SPECT-based mechanical dyssynchrony is relatively common among patients with left ventricular dysfunction. In a population of patients with predominantly ischemic heart disease referred for SPECT, a reduced EF, increasing QRS duration, severity and extent of myocardial scar on SPECT imaging are independent predictors of mechanical dyssynchrony and may serve to identify patients for dyssynchrony screening. PMID:21082299

  19. 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

  20. [Usefulness of the pre-excitation index to determine the mechanism of supraventricular paroxysmal tachycardia and the location of the anomalous pathway].

    PubMed

    Hernández González, D; Iturralde Torres, P; Colín, L; Gutiérrez, A; González Hermosillo, J A

    1990-01-01

    To evaluate the preexcitation index in determinate the mechanism of paroxysmal supraventricular tachycardia and localize accessory pathway, fifty nine patients with clinical and electrocardiographic supraventricular tachycardia were analyzed. There were thirty eight patients (64.4%) with orthodromic AV reentry using an accessory pathway for retrograde conduction and 21 patients (35.6%) with typical AV nodal reentrant tachycardia. Preexcitation of the atrium during tachycardia by premature ventricular complex at a time when anterograde His bundle activation was present in 30 o 38 (79%) patients with AV reentry while only 8 of 21 (38%) patients with AV nodal reentry demonstrated preexcitation during tachycardia. There was no significant difference between left and right accessory pathways and in mean tachycardia cycle length between the two groups. However, atrioventricular reentry demonstrated atrial preexcitation during tachycardia more frequently than AV nodal reentry. In conclusion, our findings show that the preexcitation index is a useful method for determinate the mechanism of supraventricular tachycardia and to localize accessory pathways. PMID:2378534

  1. 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

  2. Reversible postural orthostatic tachycardia syndrome

    PubMed Central

    Abdulla, Aza; Rajeevan, Thirumagal

    2015-01-01

    Postural orthostatic tachycardia syndrome (POTS) is a relatively rare syndrome recognised since 1940. It is a heterogenous condition with orthostatic intolerance due to dysautonomia and is characterised by rise in heart rate above 30 bpm from base line or to more than 120 bpm within 5-10 min of standing with or without change in blood pressure which returns to base line on resuming supine position. This condition present with various disabling symptoms such as light headedness, near syncope, fatigue, nausea, vomiting, tremor, palpitations and mental clouding, etc. However there are no identifiable signs on clinical examination and patients are often diagnosed to have anxiety disorder. The condition predominantly affects young female between the ages of 15-50 but is rarely described in older people. We describe an older patient who developed POTS which recovered over 12 mo. Recognising this condition is important as there are treatment options available to alleviate the disabling symptoms. PMID:26244158

  3. Paroxysmal Supraventricular Tachycardia: Pathophysiology, Diagnosis, and Management.

    PubMed

    Al-Zaiti, Salah S; Magdic, Kathy S

    2016-09-01

    Paroxysmal supraventricular tachycardia (PSVT) is a well-known and thoroughly studied clinical syndrome, characterized by regular tachycardia rhythm with sudden onset and abrupt termination. Most patients present with palpitations and dizziness, and their electrocardiogram demonstrates a narrow QRS complex and regular tachycardia with hidden or inverted P waves. PSVT is caused by re-entry due to the presence of inhomogeneous, accessory, or concealed conducting pathways. Hemodynamically stable patients are treated by vagal maneuvers, intravenous adenosine, diltiazem, or verapamil, hemodynamically unstable patients are treated by cardioversion. Patients with symptomatic and recurrent PSVT can be treated with long-term drug treatment or catheter ablation. PMID:27484659

  4. Epidemiology and definition of inappropriate sinus tachycardia.

    PubMed

    Pellegrini, Cara N; Scheinman, Melvin M

    2016-06-01

    Inappropriate sinus tachycardia (IST) is a clinical syndrome lacking formal diagnostic criteria. It is generally defined as an elevated resting heart rate (HR; >90-100 bpm) with an exaggerated response to physical or emotional stress and a clearly sinus mechanism. Clinical manifestations are broad from a complete lack of symptoms to incapacitating incessant tachycardia. Now understood to be relatively prevalent, it is observed to have a generally benign prognosis, though symptoms may persist for years. Whether IST is a single discrete entity or a heterogeneous condition with overlap to other syndromes such as postural orthostatic tachycardia syndrome remains a matter of debate. PMID:26310298

  5. Management of Postural Tachycardia Syndrome, Inappropriate Sinus Tachycardia and Vasovagal Syncope

    PubMed Central

    Raj, Satish

    2016-01-01

    Postural tachycardia syndrome (POTS), inappropriate sinus tachycardia (IST) and vasovagal syncope (VVS) are relatively common clinical syndromes that are seen by physicians in several disciplines. They are often not well recognised and are poorly understood by physicians, are associated with significant morbidity and cause significant frustration for both patients and their physicians. The 2015 Heart Rhythm Society Expert Consensus Statement on the Diagnosis and Treatment of Postural Tachycardia Syndrome, Inappropriate Sinus Tachycardia and Vasovagal Syncope provides physicians with an introduction to these disorders and initial recommendations on their investigation and treatment. Here we summarise the consensus statement to help physicians in the management of patients with these frequently distressing problems.

  6. [Initial evaluation and management of paroxysmal supraventricular tachycardia].

    PubMed

    Rujic, Dragana; Sundbøll, Jens; Tofig, Bawer Jalal; Nielsen, Jens Cosedis; Pareek, Manan

    2016-01-18

    The paroxysmal supraventricular tachycardias (SVT) are commonly encountered arrhythmias and include atrioventricular nodal re-entrant tachycardia, atrioventricular reciprocating tachycardia, and focal atrial tachycardia. These tachycardias share several clinical features as well as similar management strategies. The probable mechanism of paroxysmal SVT can often be diagnosed from the clinical findings and a 12-lead ECG. This review describes the initial evaluation and treatment of patients with paroxysmal SVT, including distinctive features from the most important differential diagnoses. PMID:26815585

  7. Confounders of Vasovagal Syncope: Postural Tachycardia Syndrome

    PubMed Central

    Nwazue, Victor C.; Raj, Satish R

    2012-01-01

    Most patients who present to a cardiologist with syncope will have vasovagal (reflex) syncope. A busy syncope practice will often also see patients with postural tachycardia syndrome, often presenting with severe recurrent presyncope. Recognition of this “syncope confounder” might be difficult without adequate knowledge of their presentation, and this can adversely affect optimal management. Patients with postural tachycardia syndrome exhibit an excessive increase in heart rate ≥ 30 bpm within 10 minutes of standing (in the absence of orthostatic hypotension), in addition to chronic symptoms of orthostatic intolerance. Postural tachycardia syndrome can often be differentiated from vasovagal syncope by its hemodynamic pattern during tilt table test and differing clinical characteristics. This article will briefly review the presentation of postural tachycardia syndrome, its putative pathophysiology and an approach to non-pharmacological and pharmacological management. PMID:23217691

  8. [Differential diagnosis of a narrow QRS tachycardia].

    PubMed

    Lewalter, Thorsten

    2015-09-01

    The differential diagnosis of a narrow QRS tachycardia requires on the one hand knowledge about the clinical data of the tachycardia patient but on the other hand a systematic step by step analysis of the electrocardiogram (ECG) is the most successful approach. Apart from the question of regularity or irregularity of the QRS complexes, the presence and detection of P waves is also of importance. The P wave timing in relation to the preceding and the following QRS complexes as well as the numerical relationship of P waves and QRS complexes allow a well-founded suspected diagnosis to be achieved in most cases. Even the differentiation between atrioventricular (AV) nodal reentrant tachycardia (AVNRT) versus orthodromic AV reentrant tachycardia (AVRT), e.g. by accessory leads, is in most cases possible in a surface ECG. Obviously, there are constellations which need an invasive electrophysiological procedure for a definitive diagnosis. PMID:26287273

  9. Ventricular arrhythmias in dilated cardiomyopathy as an independent prognostic hallmark. Italian Multicenter Cardiomyopathy Study (SPIC) Group.

    PubMed

    De Maria, R; Gavazzi, A; Caroli, A; Ometto, R; Biagini, A; Camerini, F

    1992-06-01

    Prevalence and characteristics of ventricular arrhythmias (VA) on Holter monitoring were evaluated in 218 patients with invasively documented idiopathic dilated cardiomyopathy to clarify their relation to pump dysfunction, and their prognostic role. VA were observed in 205 patients (94%) and were high grade (ventricular pairs or tachycardia) in 130 (60%). No simple or multiform ventricular premature complexes were present in 88 patients (group 1; 41%), ventricular pairs in 63 (group 2; 32%), and ventricular tachycardia in 67 (group 3; 27%). Only echocardiographic right ventricular dimensions (p less than 0.05) and prevalence of VA during effort (8% in group 1, 15% in group 2, and 14% in group 3; p = 0.0005) differed significantly between groups. VA severity, and number of ventricular premature beats and tachycardia episodes were not correlated to right/left ventricular dimensions and pump function indexes. During a mean follow-up of 29 +/- 16 months, 27 patients died from cardiac events, and 16 received transplants. Three-year survival probability was lower in groups 2 (0.82) and 3 (0.81) than in group 1 (0.94). By Cox multivariate analysis, VA severity (p less than 0.01) was a major independent predictor of prognosis after markers of ventricular dysfunction such as left ventricular ejection fraction (p less than 0.001) and stroke work index (p less than 0.001). PMID:1590236

  10. 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