Ventricular arrhythmias in the elderly: prevalence, mechanisms, and therapeutic implications.

Aging is associated with an increase in both the prevalence and complexity of ventricular ectopic beats (VEB), whether detected by resting ECG, 24-hour ambulatory monitoring, or exercise testing. Frequent and/or multiform VEB, ventricular couplets, and short runs of ventricular tachycardia have been detected by these techniques in a sizeable percentage of apparently healthy subjects in the seventh decade and beyond. Although the mechanism for the increase in VEB with advancing age is uncertain, possibilities include latent coronary artery disease, left ventricular hypertrophy or dilatation, elevated plasma catecholamines, and a relative prolongation of the QT interval. Because the age-related increase in VEB does not appear to increase cardiac mortality in older subjects without demonstrable heart disease, and given the significant likelihood of adverse effects from antiarrhythmic drugs in their age group, these drugs should be reserved for elderly patients with organic heart disease and frequent or complex VEB.