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Monomorphic VT (monomorphic + vt)
Selected AbstractsMode of Induction of Ventricular Tachycardia and Prognosis in Patients with Coronary Disease: The Multicenter UnSustained Tachycardia Trial (MUSTT)JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2009JONATHAN P. PICCINI M.D. Introduction: Programmed stimulation is an important prognostic tool in the evaluation of patients with an ejection fraction ,40% after myocardial infarction. Many believe that ventricular tachycardia (VT) requiring 3 ventricular extrastimuli (VES) for induction is less likely to occur spontaneously and has less predictive value. However, it is unknown whether the mode of VT induction is associated with long-term prognosis. Methods and Results: We analyzed a cohort of 371 patients enrolled in MUSTT who had inducible monomorphic VT and who were not treated with antiarrhythmic drugs or an implantable cardioverter defibrillator during the trial. Patients in whom sustained VT was induced with 1 or 2 VES or burst pacing (single VES n = 15, double VES n = 127, burst n = 7, total n = 149) were compared with those in whom VT was induced with 3 VES (n = 222). Compared with the others, patients requiring 3 VES were closer to their most recent myocardial infarction (17 vs 51 months, P = 0.035) and showed a trend toward a lower ejection fraction (26% vs 30%, P = 0.057). VT requiring 3 VES had a shorter cycle length (240 vs 260 ms, P < 0.001). Despite these findings, there was no difference in the incidence of arrhythmic death or cardiac arrest (HR 1.02; 95% CI 0.69-1.51) or all-cause mortality (HR 1.03; 95% CI 0.76-1.39) according to the mode of induction in adjusted analyses. Conclusions: The prognostic significance of VT induced by 3 VES is similar to that of VT induced by 1 or 2 VES, or burst pacing, in patients with coronary disease and abnormal LV function. [source] Clustering of Ventricular Tachyarrhythmias in Heart Failure Patients Implanted with a Biventricular Cardioverter DefibrillatorJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2006MAURIZIO LUNATI M.D. Background: Temporal patterns of ventricular tachyarrhythmia (VT/VF) have been studied only in patients who have received implantable cardioverter defibrillators (ICD) for secondary prevention of sudden death, and mainly in ischemic patients. The aim of this study was to evaluate VT/VF recurrence patterns in heart failure (HF) patients with biventricular ICD and to stratify results according to HF etiology and ICD indication. Methods and Results: We studied 421 patients (91% male, 66 ± 9 years). HF etiology was ischemic in 292 patients and nonischemic in 129. ICD indication was for primary prevention in 227 patients and secondary prevention in 194. Baseline left ventricular ejection fraction (LVEF) was 26 ± 7%, QRS duration 168 ± 32 msec, and NYHA class 2.9 ± 0.6. In a follow-up of 19 ± 11 months, 1,838 VT/VF in 110 patients were appropriately detected. In 59 patients who had ,4 episodes, we tried to determine whether VT/VF occurred randomly or rather tended to cluster by fitting the frequency distribution of tachycardia interdetection intervals with exponential functions: VT/VF clusters were observed in 46 patients (78% of the subgroup of patients with ,4 episodes and 11% of the overall population). On multivariate logistic analysis, VT/VF clusters were significantly (P < 0.01) associated with ICD indication for secondary prevention (odds ratio [OR]= 3.12; confidence interval [CI]= 1.56,6.92), nonischemic HF etiology (OR = 4.34; CI = 2.02,9.32), monomorphic VT (OR = 4.96; CI = 2.28,10.8), and LVEF < 25% (OR = 3.34; CI = 1.54,7.23). Cardiovascular hospitalizations and deaths occurred more frequently in cluster (21/46 [46%]) than in noncluster patients (63/375 (17%), P < 0.0001). Conclusions: In HF patients with biventricular ICDs, VT/VF clusters may be regarded as the epiphenomenon of HF deterioration or as a marker of suboptimal response to cardiac resynchronization therapy. [source] Analysis of the Pattern of Initiation of Sustained Ventricular Arrhythmias in Patients with Implantable DefibrillatorsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2000ERIC TAYLOR M.D. Initiation of Sustained Ventricular Arrhythmias. Introduction: The purpose of this study was to analyze the pattern of initiation of sustained ventricular arrhythmias in patients with varying types of underlying structural heart disease. Methods and Results: The study group consisted of 90 patients with an implantable cardioverter defibrillator. Cardiovascular diagnoses included coronary artery disease in 64 patients (71%). The patients were divided into four groups based on the type and severity of structural heart disease. Two hundred sixty episodes of sustained ventricular arrhythmias were analyzed. The mean coupling interval of the initiating heat of all ventricular arrhythmias was 523 ± 171 msec. The coupling interval of the initiating beat was longer in patients with impaired ventricular function, particularly those with nonischemic dilated cardiomyopathy. The prematurity index was similar regardless of the type of underlying structural heart disease. However, the prematurity index was shorter in patients with polymorphic ventricular tachycardia (VT) compared to those with monomorphic VT. A pause was observed more commonly before the onset of polymorphic VT/ventricular fibrillation than sustained monomorphic VT. Two hundred twenty-two (85%) of the arrhythmia episodes were initiated by a late-coupled premature beat, 33 (13%) were initiated by an early-coupled premature beat, and 5 episodes (2%) were initiated with a short-long-short sequence. The patttern of initiation of the ventricular arrhythmias was similar in all patient groups and for both monomorphic and polymorphic tachycardias. Conclusion: These findings demonstrate that sustained ventricular arrhythmias typically are initiated by late-coupled ventricular premature depolarizations, regardless of the type or severity of underlying structural heart disease or resultant arrhythmia. [source] Standardized Stimulation Protocol to Predict the Long-Term Success of Radiofrequency Ablation of Postinfarction Ventricular TachycardiaPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003DAVID O'DONNELL O'DONNELL, D., et al.: Standardized Stimulation Protocol to Predict the Long-Term Success of Radiofrequency Ablation of Postinfarction Ventricular Tachycardia.Background: The ability to predict the success of radiofrequency ablation (RFA) is an essential step in the management of ventricular tachycardia (VT) in patients with ischemic heart disease. Methods: This study tested a standardized programmed stimulation protocol and pre-specified definitions of procedural outcome. Consecutive patients referred for RFA of delayed post infarction VT were enrolled. Programmed stimulation was performed at the beginning and the end of an RFA procedure, and consisted of an 8 beat drive followed by up to 5 extrastimuli. Immediate success was defined as no inducible monomorphic VT, and a modified result was defined as the inducibility of VT with >2 extrastimuli beyond those required at baseline. Procedural failure was defined when these criteria were not met. Recurrences of sustained VT and arrhythmic deaths were monitored during long-term follow-up. Results: The study enrolled 112 patients. Immediate procedural success was achieved in 38%, a modified result in 34%, and procedural failure in 28% of patients. During a mean follow-up of 78 ± 16 months, recurrent sustained VT was observed in 25 patients. VT recurrence was 3% (3/79) in patients with a successful or modified result, compared with 67% (22/33) in those who had undergone unsuccessful procedures (P < 0.001). Conclusions: This standardized stimulation protocol and definitions of procedural success, enabled us to predict with high accuracy a VT recurrence-free long-term follow-up. This may have implications in recommending devices or other treatments after RFA for postinfarction VT. (PACE 2003; 26[Pt. II]:348,351) [source] Ventricular Dyssynchrony and Risk Markers of Ventricular Arrhythmias in Nonischemic Dilated Cardiomyopathy:PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003A Study with Phase Analysis of Angioscintigraphy FAUCHIER, L.,et al.: Ventricular Dyssynchrony and Risk Markers of Ventricular Arrhythmias in Nonischemic Dilated Cardiomyopathy: A Study with Phase Analysis of Angioscintigraphy.Biventricular pacing is a new form of treatment for patients with dilated cardiomyopathy and ventricular dyssynchrony. Limited information is available regarding the relationship between ventricular dyssynchrony and risk markers of ventricular arrhythmias in idiopathic dilated cardiomyopathy (IDC). In 103 patients with IDC, Fourier phase analysis of both ventricles was performed from equilibrium radionuclide angiography (ERNA). The difference between the mean phase of the LV and RV was a measure of interventricular dyssynchrony, and the standard deviations of the mean phases in each ventricle measured intraventricular dyssynchrony. There were no significant differences in inter- and intraventricular dyssynchrony between patients with versus without histories of sustained VT or VF, nonsustained VT, abnormal signal-averaged ECG, or induced sustained monomorphic VT. Dyssynchrony was not related to decreased heart rate variability (HRV). LV and interventricular dyssynchrony were weakly related to QT duration and QT dispersion. During a follow-up of27 ± 23 months, 21 patients had major adverse cardiac events (MACE), including 7 cardiac deaths, 11 progression of heart failure leading to cardiac transplantation, and 3 sustained VT/VF. The only independent predictors of MACE were an increased standard deviation of LV mean phase (P = 0.003), a decreased HRV (standard deviation of normal-to-normal intervals, P = 0.004), and histories of previous VT/VF (P = 0.03) or nonsustained VT (P = 0.04). In conclusion, left intraventricular dyssynchrony evaluated with ERNA was an independent predictor of MACE in IDC and was not related to usual risk markers of ventricular arrhythmias. This may have implications for resynchronization therapy and/or the use of implantable cardioverter defibrillators in IDC. (PACE 2003; 26[Pt. II]:352,356) [source] Ventricular tachyarrhythmia associated with cardiac sarcoidosis: Its mechanisms and outcomeCLINICAL CARDIOLOGY, Issue 4 2004Hiroshi Furushima M.D. Abstract Background: Cardiac sarcoidosis is increasingly recognized and is associated with poor prognosis. Ventricular tachycardia (VT) associated with cardiac sarcoidosis is the most likely cause of sudden death in most patients, but the mechanism has not been well established. Hypothesis: This study investigated the mechanisms and outcome of VT associated with cardiac sarcoidosis. Methods: The study included eight consecutive patients (five men, three women, aged 54 ± 19 years) who had sustained monomorphic VT associated with cardiac sarcoidosis in our hospital. Results: The average ejection fraction was 43 ± 11%. Twenty-two VTs were observed in these patients, and mean heart rate during VT was 192 ± 29 beats/min (range 144,259). The phenomenon of transient entrainment was documented in 10 of 22 (45%) VTs by ventricular pacing (eight in the active phase). Another five (23%) VTs could not be entrained, but could be initiated by programmed stimulation and terminated by rapid pacing, reproducibly. In 3 of the 22 (14%) VTs, cardioversion was required urgently because of the fast rate, while the remaining 4 (18%) could be induced during electrophysiologic study. Conclusions: In this study, there was a high possibility that the mechanism of 15 (68%) VTs was reentry. Reentrant substrate is formed not only in association with the healing of cardiac granulomas in the inactive phase of cardiac sarcoidosis but also in the active phase. Ventricular tachycardia with cardiac sarcoidosis, even if this mechanism is reentry, has different inducibility between the active and inactive phases in an electrophysiologic study. This makes the therapy for cardiac sarcoidosis (e.g., corticosteroids, antiarrhythmic agents, and catheter ablation) difficult. The implantable cardioverter-defibrillator is an effective treatment for ventricular tachyarrythmia with cardiac sarcoidosis. [source] | ||||||||||