VENTRICULAR ARRHYTHMIAS IN HYPERTENSIVE PATIENTS WITH AND WITHOUT LEFT-VENTRICULAR HYPERTROPHY

Hypertensive patients with left ventricular hypertrophy have more risk of sudden death than those who don't have it. We studied with 24 hour ambulatory electrocardiographic monitoring the presence of ventricular arrhythmias in 24 treated hypertensive patients, 12 of which had left ventricular hypertrophy by electrocardiographic criteria (group III) and in 12 patients who did not have it (group II). 12 normotensive patients seved as a control group (group I). The three groups of patients didn't present any significant statistical difference concerning age, sex, weight, height, antihypertensive therapy, smoking habits, and levels of serum potassium, cholesterol and HDL cholesterol in blood. None of them were receiving antiarrhythmic drugs. We excluded the presence of coronary artery desease on clinical ground and by making a radionuclide angiocardiography with technetium-99 m. at rest and during exercise. We obtained the following results: 2 patients (16,67%) from group II, had one episode of nonsustained ventricular tachycardia, 3 patients (25%) of the same group and 2 (16,67%) from group II, had ventricular couplets. Frequent ventricular extrasystoles (> than 30 per hour) were observed in 5 patients (41,66%) of group III (p < 0.01 respect group I) and in 1 patient (8,33%) of group II (p < 0.05 respect group III). The presence of complex ventricular arrythmias (episodes of ventricular tachycardia and couplets) didn't show any relation with the level of serum potassium, but were related to the administration of diuretics. These arrythmias were only found in the patients that were being treated with this type of drug. The patients with complex ventricular arrythmias had a higher left ventricular mass index by echocardiography, but the difference didn't reach statistical difference. Our work suggest, in spite of the small number of patients studied, that ventricular arrhytmias are frecuent in hypertensive patients with left ventricular hypertrophy and that there is a relation with diuretic theraphy. This may contribute to the higher incidence of sudden death seen in these patients.