“Stable” Ventricular Tachycardia Is Not a Benign Rhythm

Abstract

Background —Sustained ventricular tachycardia (VT) can be unstable, can be associated with serious symptoms, or can be stable and relatively free of symptoms. Patients with unstable VT are at high risk for sudden death and are best treated with an implantable defibrillator. The prognosis of patients with stable VT is controversial, and it is unknown whether implantable cardioverter-defibrillator therapy is beneficial. Methods and Results —Screening for the Antiarrhythmics Versus Implantable Defibrillators (AVID) trial identified patients with both stable and unstable VT. Both groups were included in a registry, and their clinical characteristics and discharge treatments were recorded. Mortality data were obtained through the National Death Index. The mortality in 440 patients with stable VT tended to be greater than that observed in 1029 patients presenting with unstable VT (33.6% versus 27.6% at 3 years; relative risk [RR]=1.22; P =0.07). After adjustment for baseline and treatment differences, the RR was little changed (RR=1.25, P =0.06). Conclusions —Sustained VT without serious symptoms or hemodynamic compromise is associated with a high mortality rate and may be a marker for a substrate capable of producing a more malignant arrhythmia. Implantable cardioverter-defibrillator therapy may be indicated in patients presenting with stable VT.

Task Force on Sudden Cardiac Death of the European Society of Cardiology

“…Data from the CIDS [248] and AVID [249] suggest that patients with syncope and otherwise documented VT as well as patients with haemodynamically stable VT present a high risk of all-cause mortality during the intermediate follow-up. In the former study, annual all-cause mortality was 13·4% in 91 patients with syncope and 8·7% in all other 568 patients.…”

Sustained ventricular tachycardia in structural heart disease

“…The adverse outcome of these patients is similar to that of patients with unstable VT [17,18]. Moreover, benefit of ICD therapy appears to be not different in patients presenting with VT or VF.…”

“…In patients with Chagas disease SMVT can also occur in the absence of severe LV dysfunction and, hence, be hemodynamically stable. Nonetheless, 2 retrospective analyses of the AVID Registry showed that the hemodynamic impact of the qualifying arrhythmia was not a predictor of outcome [17,18]. VT is often poorly tolerated leading to syncope and sudden cardiac death.…”

Secondary prevention of sudden cardiac death

“… 4 Similarly, when longitudinal outcomes were evaluated in patients with “stable” VT without hemodynamic compromise, 3-year mortality remained high (34%), although it is important to note that this “stable VT” cohort reflected patients with LV dysfunction (mean LVEF 34% ± 13%). 17 …”