Comparative effects of ibopamine and captopril in mild congestive heart failure. Focus on the long-term effects of inodilation on ventricular arrhythmias.

Twenty-three patients with mild heart failure (I-II NYHA classes) on digitalis and diuretics were assigned to the following treatment in a random and double-blind fashion: ibopamine-captopril, ibopamine-placebo, captopril-placebo, and placebo-placebo. The doses of captopril and ibopamine were respectively 25 mg t.i.d. and 100 mg t.i.d. The incremental exercise time (until exhaustion) and the peak VO2 (oxygen consumption), the indexes of left ventricular function (by echo and nuclear stethoscope) and ventricular arrhythmias (evaluated by prolonged Holter monitoring) were assessed before randomization, at 45 days and at 3 months. Ejection fraction, exercise time, peak VO2, ventricular arrhythmias and heart rate (at rest and during exercise) appeared to be equally unaffected by each treatment. Our results show that ibopamine exerts no significant effects on either heart rate or ventricular arrhythmias and that indexes of left ventricular function are not modified by any treatment in mild congestive heart failure.

Impaired renal functional reserve and albuminuria in essential hypertension.

The stimulatory effects of an infusion of amino acids on glomerular filtration rate has previously been used to measure renal functional reserve and detect glomerular hyperfiltration. Thirty four patients with mild to moderate essential hypertension and seemingly normal renal function and 22 healthy controls were given infusions of amino acids to investigate whether renal functional reserve is reduced in essential hypertension and to detect patients at risk of renal damage. Although basal creatinine clearance increased after the infusion of amino acids in the controls (mean 27.9 ml/min; 95% confidence interval 18.2 to 37.6), the overall change was lower in the patients (mean 13.4 ml/min; 8.3 to 18.5), 11 of the 34 showing no increase at all. In these 11 non-responders the mean systolic blood pressure was higher than that in the 23 others (178.5 mmHg v 157 mmHg, respectively). Mean urinary albumin excretion was abnormal in the patients (93.3 mg/24 h; 44.2 to 142.4); eight of the 11 non-responders had an albumin excretion above the normal range (greater than 20 mg/24 h). In the 11 patients without renal functional reserve a positive correlation was found between basal creatinine clearance and albumin excretion (r = 0.695). As consumed renal reserve and albuminuria are markers of glomerular hyperfiltration studying renal function before and after infusion of amino acids can detect hypertensive patients at risk of progressive renal damage.

Sympathetic activation on effort in patients with chronic heart failure. Long term effects of captopril.

Ten patients with congestive heart failure (CHF) (NYHA II-IV) on adjusted doses of digitalis and diuretics underwent a careful clinical assessment including an evaluation of exertion dyspnoea and the usual echocardiographic indices of cardiac performance. A cardiopulmonary exercise test with an increment of 20W every 3 minutes was prolonged until exhaustion. Systemic arterial pressure, ECG, VO2, VCO2 and VE were monitored throughout. Gas tensions, plasma catecholamines and lactate were measured in blood samples taken at the first and third minute of each exercise stage. The above measurements were carried out before and after 3 months of treatment with Captopril, 50 mg b.i.d. or t.i.d. A highly significant correlation between arterial lactate and plasma norepinephrine (NE) was observed in each patient during both exercise tests (r = 0.77 to 0.99; p less than 0.05 at least). Left ventricular end-diastolic dimensions were reduced by Captopril (from 69.9 +/- 1.7 to 65.2 +/- 1.4 mm, p less than 0.01) along with a concomitant increase in percent fractional shortening. Most of the patients were reclassified at a lower NYHA class and a significant decrease in dyspnoea score was observed. The exercise time was significantly increased (from 11.2 +/- 1.8 to 12.9 +/- 1.9 min; p less than 0.05), but the peak values of NE, arterial lactate and VO2 were not affected by the treatment. The predicted value of VE at a VCO2 of 1 L/min, regarded as an index of dyspnoea, was significantly decreased by Captopril (from 41.4 +/- 2.9 to 38.9 +/- 2.7 L/min; p less than 0.05). The positive effects of long-term treatment with Captopril on cardiac performance in CHF are confirmed. Sympathetic activity is linked to anaerobic muscular metabolism during exercise and seems to be independent of pharmacological ACE inhibition. The discrepancy between the exercise tolerance and the peak VO2 might be explained by a better utilization of the available energy.

Efficacy of two different doses of muzolimine in the treatment of mild hypertension.

UNLABELLED: A report is given on the effects of oral therapy with muzolimine (M) in patients with mild hypertension. SUBJECTS AND METHOD: 21 untreated patients, aged 35 to 69 (mean 53.1 yrs) with orthostatic diastolic BP between 100 and 115 mmHg were randomly assigned to either group A (10 mg M/day) or group B (20 mg M/day) in a single blind study for a period of two weeks. Clinostatic and orthostatic systolic and diastolic BP and heart rate were recorded at weekly intervals. PRA, aldosteronemia, ECG and blood chemistry were analyzed at the beginning and at the end of the study. Student's t-test was used for the statistical evaluation and p values below 0.05 were considered significant. RESULTS: Both clinostatic and orthostatic diastolic BP were significantly reduced in group A whereas only orthostatic diastolic BP was decreased in group B (Fig. 1). PRA and aldosteronemia values and blood chemistry showed no statistically significant changes. No side effects were noted. We conclude that 10 mg/day of muzolimine is more effective than 20 mg/day in reducing orthostatic diastolic BP (A vs. B p less than 0.02). Although these results are only preliminary data and further investigations are required, they suggest that muzolimine may be safely used, in combination with other antihypertensive agents, particularly in cases of renal failure.