EFFECTS OF ANGIOTENSIN-CONVERTING ENZYME-INHIBITORS ON THE HEART AND VESSELS IN CLINICAL AND EXPERIMENTAL-HYPERTENSION - A REVIEW

The primary aim of antihypertensive therapy is to reduce blood pressur e. Whatever their mechanisms of action, almost all the antihypertensiv e drugs currently available can be considered to achieve this goal. Ho wever, the most common complications of hypertension (myocardial infar ction, thrombolytic stroke and sudden cardiac death) are related to st ructural cardiovascular changes rather than bring directly related to blood pressure elevation. Thus, it would appear logical that an optimu m antihypertensive:sive drug should also prevent and reverse the cardi ovascular abnormalities associated with hypertension before irreversib le damage occurs. The different classes of antihypertensive drug are i n fact largely successful in preventing or reversing these target abno rmalities, in particular cardiac and vascular abnormalities. In hypert ensive patients, angiotensin-converting enzyme (ACE) inhibitors appear to be particularly effective in achieving this goal. probably because they alter vascular wall and cardiac structure, irrespective to some extent of the haemodynamic changes they produce. ACE inhibitors may ha ve particularly beneficial effects on left ventricular mass because of their favourable interference with growth factors, an increased produ ction of bradykinin, and hence of nitric oxide, may add further benefi t. ACE inhibitors also prevent and/or reduce reactive perivascular and interstitial growth, as well as fetalisation of cardiac myocytes. Fur thermore, in common with calcium channel antagonists and nitrates, ACE inhibitors improve arterial compliance. and thus decrease cardiac loa d. Indirect evidence suggests that a reduction in left ventricular hyp ertrophy during antihypertensive therapy reverses the pathological con sequences of an increased left ventricular mass. although further stud ies are needed to assess the true clinical impact of these treatment-i nduced changes in the morbidity and mortality of hypertensive patients .