Potentials and limitations of angiotensin converting enzyme inhibition in the treatment of hypertension.

To appreciate the advantages of inhibiting the renin-angiotensin system in the treatment of hypertension it is necessary to be aware of four major failures in today's therapy of the disease: The theoretical blood pressure target (supine diastolic blood pressure of 90 to 95 mmHg) is not reached in every patient. The number of adverse effects affecting the quality of life is not acceptable. Today's antihypertensive medications have no basic physiological rationale. Although the mechanical risks of blood pressure elevation are avoided with today's therapy, coronary heart disease, the most common cardiac complication, is not significantly reduced. Converting enzyme inhibition could theoretically provide a solution to each of these failures but its advantages will have to be balanced against the potential risks. The risk of iatrogenic disease with any compound introduced chronically into a living organism for therapeutic reasons. The lack of substrate specificity and the unknown overall physiological effect of angiotensin converting enzyme.