Ventricular ectopic activity was recorded at baseline in 5.6% of the 12-lead electrocardiograms and 8.2% of the 2-minute rhythm strips of 4674 subjects with isolated systolic hypertension (systolic blood pressure 160 to 219 mm Hg, diastolic blood pressure < 90 mm Hg) participating in the Systolic Hypertension in the Elderly Program (SHEP). In this study 1.3% had 6 to 10 ventricular premature beats (VPB), and 0.7% had > 10 VPB on the 2-minute rhythm strip. Correlates of VPB presence on the 12-lead ECG were older-age male sex, presence of Q/QS pattern and higher heart rate. Participants with serum potassium < 3.5 mmol/L had a higher prevalence of VPB. Similarly, the number of VPB on the 2-minute rhythm strip was associated with male sex, increasing age, with lower serum potassium, history of palpitations, and presence of Q/QS patterns.