Prediction of Sustained Ventricular Tachycardia Inducible by Programmed Stimulation in Patients With Coronary Artery Disease

Abstract

Background-Cardiologists often use clinical variables to determine the need for electrophysiological studies to stratify patients for risk of sudden death. It is not clear whether this is rational in patients with coronary artery disease, left ventricular dysfunction, and nonsustained ventricular tachycardia. Methods and Results-We analyzed the first 1721 patients enrolled in the Multicenter UnSustained Tachycardia Trial to determine whether clinical variables could predict which patients would have inducible sustained monomorphic ventricular tachycardia. The rate of inducibility of sustained ventricular tachycardia was significantly higher in patients with a history of myocardial infarction and in men compared with women. There was a progressively increased rate of inducibility with increasing numbers of diseased coronary arteries. There was a significantly lower rate of inducibility in patients with prior coronary artery bypass surgery and in patients who also had noncoronary cardiac disease. The rate of inducibility was higher in patients of white race, patients with recent (Յ6 weeks) angina, left ventricular dyskinesis, and in patients with greater numbers of fixed thallium defects. Inducibility was more likely in patients who had a prior myocardial infarction complicated by congestive heart failure, ventricular tachycardia, or fibrillation Յ48 hours after the onset of infarction. Although these associations are statistically significant, the accuracy of the clinical variables in discriminating between patients with and those without inducible ventricular tachycardia is only modest (receiver operator characteristic area Ͻ0.70). Conclusions-Multiple clinical variables are independently associated with inducible sustained ventricular tachycardia.However, they have limited utility to guide clinical decisions regarding the use of electrophysiological testing for risk stratification in this patient population.

Infarct morphology identifies patients with substrate for sustained ventricular tachycardia

“…ACE-I ϭ angiotensin-converting enzyme inhibitor; CHF ϭ congestive heart failure; EPS ϭ electrophysiologic study; HTN ϭ hypertension; LV ϭ left ventricle; MI ϭ myocardial infarction; NSVT ϭ nonsustained ventricular tachycardia; PTCA ϭ percutaneous transluminal coronary angioplasty; SA ϭ surface area; VF ϭ ventricular fibrillation; VT ϭ ventricular tachycardia; WMA ϭ wall motion abnormality. mans, limited information suggests that infarct size, as measured by LVEF, maximum creatine kinase, and the number of fixed thallium defects, is related to induction of ventricular arrhythmias (1,(27)(28)(29)(30)(31). Based on autopsy findings, Bolick et al (4) reported that patients with clinical VT after myocardial infarction had larger infarcts than those without.…”

Impact of Sex and Ethnicity on Arrhythmic Risk

“…In the Multicenter Unsustained Tachycardia Trial population of patients with coronary artery disease, left ventricular ejection fraction of <40 %, and asymptomatic nonsustained ventricular arrhythmia, women were significantly less likely to have inducible ventricular tachycardia compared to men [50]. The decreased risk of ventricular arrhythmias in women with ischemic cardiomyopathy and heart failure has raised questions as to whether the substrate for life-threatening ventricular arrhythmias in women differs enough to warrant withholding ICD therapy [51,52].…”

Gender differences in ventricular arrhythmia recurrence in patients with coronary artery disease and implantable cardioverter-defibrillators

“…There are few data comparing the incidence of sustained arrhythmia between men and women, and existing studies have been limited to survivors of cardiac arrest (5)(6)(7)(8). Gender differences have been noted in inducibility of ventricular arrhythmias among patients with CAD (9,10) and in frequency of nonsustained ventricular tachycardia (VT) in patients with congestive heart failure (11), suggesting that men may have greater propensity to ventricular arrhythmia.…”