RAMIPRIL - AN UPDATED REVIEW OF ITS THERAPEUTIC USE IN ESSENTIAL-HYPERTENSION AND HEART-FAILURE

Ramipril is a second generation angiotensin converting enzyme (ACE) in hibitor Like enalapril, it is a prodrug and is hydrolysed in vivo to r elease the active metabolite, ramiprilat which has a long elimination half-life permitting once-daily administration. The antihypertensive e fficacy of ramipril has been confirmed in large-scale noncomparative s tudies conducted in general practice as well as in more rigorously con trolled clinical trials. In the former; approximately 85% of patients with mild to moderate essential hypertension have responded successful ly to treatment with ramipril 2.5 or 5 mg/day, while comparative trial s indicate that the antihypertensive efficacy of the drug is equivalen t to that of other established ACE inhibitors and the beta-adrenocepto r antagonist atenolol. As expected, the response rate to ramipril mono therapy is lower in patients with severe hypertension (around 40%), al though the blood pressure lowering effect can be enhanced with the add ition of a diuretic such as hydrochlorothiazide or piretanide. The ant ihypertensive efficacy of ramipril is maintained in patients with diab etes mellitus and preliminary data indicate that the drug has the bene ficial effect of decreasing urinary albumin excretion in diabetic pati ents with nephropathy. Ramipril is superior to atenolol in causing reg ression of left ventricular hypertrophy, although the clinical signifi cance of this effect per se remains to be established. The large-scale Acute Infarction Ramipril Efficacy (AIRE) study demonstrated that ram ipril 5 or 10 mg/day significantly decreased the risk of all-cause mor tality by 27% in patients with clinical evidence of heart failure afte r acute myocardial infarction, even if transient. The beneficial effec t of ramipril was apparent by 30 days of treatment and appeared to be greatest in patients with more severe ventricular damage after infarct ion. Ramipril is well tolerated in general practice, with 5% or fewer patients discontinuing therapy because of drug intolerance. The data a vailable suggest that ramipril shares a similar tolerability profile t o that of other established ACE inhibitors. Thus, clinical data confir m ramipril as a useful alternative ACE inhibitor for the treatment of patients with mild to moderate hypertension, and indicate a beneficial effect of the drug inpatients with clinical evidence of heart failure after acute myocardial infarction. It is also reasonable to assume th at ramipril will be of value in the treatment of patients with more es tablished heart failure or asymptomatic left ventricular dysfunction.