Treatment of persistent ventricular tachycardia: Drugs or ablation?

Implantable cardioverter defibrillators (ICDs) reduce the mortality risk associated with recurrent ventricular tachycardia (VT) and can frequently terminate VT episodes painlessly, but do not prevent recurrent episodes. For patients with symptomatic recurrences, frequent asymptomatic recurrences, ICD shocks, or VT storm, most clinicians recommend strategies to suppress VT. The proarrhythmic mortality risk of antiarrhythmic drugs (AADs) may be mitigated by the presence of an ICD, but these medications are limited by high recurrence rates, and unfavorable side effect profiles. Catheter ablation is an alternative or adjunctive option, but is also limited by incomplete efficacy and procedural risk.     

Could sustained monomorphic ventricular tachycardia in the early phase of a prime acute myocardial infarction affect patient outcome?

Objectives

Sustained monomorphic ventricular tachycardia (SMVT) in the course of a prime acute myocardial infarction is not a common arrhythmia and its prognostic significance has not been specifically elucidated. The aim of the study was to estimate the prognostic implications of the occurrence of sustained monomorphic ventricular tachycardia in the early phase (<72 h) of a prime acute myocardial infarction.

Methods

We studied 690 consecutive patients admitted to the coronary care unit with a diagnosis of a prime myocardial infarction. SMVT was observed in 18 (2.6%) patients and we followed these patients for establishing the prognostic value of the arrhythmia according to the clinical characteristics.

Results

Patients with SMVT had a more extensive myocardial infarction based on the peak of the CK-MB isoenzyme activity (480±290 IU/L, vs 270±190 IU/L, P < .01), and higher mortality rate (40% vs 9%, P < .001). The independent predictors of SMVT were CK-MB (odds ratio [OR] 12.4), presence of complex ventricular arrhythmias (OR = 5.7), a wide QRS complex ≥130 milliseconds (OR = 4.8) and Killip class (OR = 4.8). The SMVT was itself an independent predictor of mortality (OR = 5.0). Compared with patients with ventricular fibrillation or polymorphic ventricular tachycardia, those with SMVT had a higher CK-MB activity, higher rate of wide QRS ≥130 milliseconds (33% vs 8%, P < .002), had a worse hemodynamic condition (Killip class >I:58% vs 23%, P < .04) and higher recurrence rate of ischemic events (68% vs 16%, P < .05). During the one year follow-up period, 4 patients (36.3%) of the 11 survivors from those with SMVT died of cardiac related causes.

Conclusions

SMVT during the first 72 h of a prime myocardial infarction is an index of a larger healing myocardium with acute very complexed electrophysiological changes and it is an independent predictor of in-hospital mortality and a prognostic factor of a poor one year outcome.     

What is the risk of sudden cardiac death in patients presenting with hemodynamically stable sustained ventricular tachycardia after myocardial infarction?

Objectives. This study sought to determine the long-term risk of sudden cardiac death in patients with hemodynamically stable sustained ventricular tachycardia complicating coronary artery disease.Background. The prognosis and risk of sudden cardiac death in patients with a history of myocardial infarction and ventricular tachyarrhythmias have not been clearly defined. Prior studies are limited by a short follow-up period and by inclusion of patients with heterogeneous cardiac diseases and presenting arrhythmias.Methods. A retrospective cohort analysis was performed on data from 124 patients, followed up for a mean of 36 ± 30 months, who received electrophysiologically guided therapy for hemodynamically stable ventricular tachycardia after remote myocardial infarction.Results. Seventy-eight patients were treated pharmacologically (medical group), and 46 patients underwent map-guided subendocardial resection (surgical group). Nine patients (7.3%) died suddenly, 5 (4.0%) died of noncardiac causes, 9 (7.3%) died of a perioperative complication, and 20 (23.4%) died of other cardiac causes. At 1, 2 and 3 years, sudden death occured at cumulative rates of 2 ± 1%, 3 ± 2% and 7 ± 3%, whereas total mortality was 20 ± 4%, 28 ± 4% and 32 ± 5% (mean ± SD). Sudden cardiac death (p = 0.047) and total mortality (p = 0.036) were higher in patients with multivessel disease and were similar for both treatment groups.Conclusions. Although the overall mortality in postinfarction patients presenting with hemodynamically stable ventricular tachycardia treated with electrophysiologically guided antiarrhythmic therapy is high, the risk of sudden death in these patients appears to be low (average 2.4%/year).     

Repetitive ventricular tachycardia in a syncopal child: Cause or incidental finding ?

A 15‐year‐old girl suffered recurrent syncopal episodes during 7 years. Events were precipitated by exercise or emotional stress, leading to the diagnosis of reflex syncope. Exercise testing induced recurrent salvos of nonsustained right ventricular outflow tract tachycardia. This arrhythmia is often asymptomatic, reflex syncope is very frequent and both causes are related to the same triggering situations. It was therefore essential to obtain recordings during syncopal events and to observe the clinical evolution under effective treatment in order to make the right diagnosis.