Asymptomatic patients who do not have heart disease have long-term prognoses very similar to the general population, but asymptomatic patients with ejection fractions greater than 40% have a 3.5% incidence of sustained ventricular tachycardia or cardiac arrest. Emerging data also suggest that very frequent ventricular ectopy may be associated with cardiomyopathy through a mechanism thought to be similar to that of chronic right ventricular pacing associated cardiomyopathy. And for patients with underlying chronic structural heart disease and complex ectopy, mortality is significantly increased.