gms | German Medical Science

There is evidence for blood pressure independent effects of aldosterone on left ventricular structure and function. We examined whether a low dose of spironolactone (spiro) that does not lower blood pressure improves parameters of left ventricular structure and function in young male hypertensives.

We conducted a randomized placebo controlled cross-over study in 26 otherwise healthy, young male volunteers with never treated essential hypertension (stage 1 and 2). Patients were treated with spiro 25 mg and placebo for 4 weeks according to the two-fold cross-over design. At the end of each treatment phase ambulatory blood pressure measurement and echocardiography/dopplerechocardiography were performed. Primary endpoint of the study was left ventricular mass index, secondary endpoints were systolic and diastolic left ventricular function.

Treatment with spiro reduced LVMI (114.8 ± 3.9 vs. 106.5 ± 3.3 g/m2 , p=0.018). This difference is based on a decrease in diastolic left ventricular diameter (51.6 ± 0.9 vs. 53.2 ± 0.9 mm, p=0.046) and a decrease in septal wall thickness (9.6 ± 0.2 vs. 9.9 ± 0.3 mm, p=0.142) without a change in left ventricular posterior wall thickness (9.0 ± 0.3 vs. 9.0 ± 0.2 mm, p=0.9). Parameters of left ventricular systolic and diastolic function were unchanged. Mean 24-hour-blood pressure was 129.2 ± 1.2 / 75.3 ± 1.8 mmHg with spiro treatment and 130.3 ± 1.5 / 74.1± 3.0 mmHg with placebo treatment (p=0.358 for systolic and p=0.643 for diastolic blood pressure). There was no difference in sodium and potassium serum levels. Urinary-sodium excretion was increased in the spiro period (226.5 ± 29.2 vs. 206.8 ± 25.8 mmol/24h), whereas potassium excretion was unchanged.

In this study we can show a reduction of left ventricular mass by a short term treatment with a low dose spironolactone without a change in blood pressure. This might be a combined effect of direct action of spiro on cardiac mineralocorticoid receptors together with increased natriuresis.