Cardiac arrhythmias as correlated with the circadian rhythm of arterial pressure in hypertensive subjects with and without left ventricular hypertrophy

To evaluate the relationship among supraventricular and ventricular arrhythmias with blood pressure and heart rate (HR) values, we studied 2 groups of 20 hypertensive men with (group I) and without (group II) left ventricular hypertrophy. Ambulatory electrocardiographic tracings were recorded continuously, together with ambulatory arterial pressure. Systolic (SBP) and diastolic (DBP) blood pressure values measured over 24 h showed no difference between the two groups, but we found greater variability in SBP in group I. The incidence of ventricular and supraventricular arrhythmias was significantly higher in patients of group I; moreover, we found a strong correlation between the incidence of ventricular extrasystoles (VPCs) and SBP, DBP, and HR values in group I, whereas in group II the incidence of supraventricular extrasystoles (APCs) was higher during peaks of SBP and HR values. The relationship between APCs and SBP observed in group II may be attributable to the pressure stimulus on a normal atrium, and the significant correlation between VPCs and SBP, DBP, and HR values may be due to episodes of subendocardial ischemia or to the influence of adrenergic stimulation on previously compromised myocardial tissue.