Antihypertensive Drugs and Cardiac Trophic Mechanisms

In hypertension, increased systolic blood pressure (BP) and the resulting increase in systolic wall stress are major determinants of the degree of left ventricular hypertrophy (LVH). Antihypertensive drugs all decrease BP, but different classes of these drugs may activate other trophic mechanisms and therefore may have different effects on LVH. Angiotensin-converting enzyme (ACE) inhibitors decrease the major cardiac growth-promoting factors such as systolic wall stress, diastolic wall stress, and cardiac sympathetic and renin activity, and consistently cause regression of LVH. On the other end of the drug spectrum, arterial vasodilators may decrease systolic wall stress, but increase diastolic wall stress and cardiac sympathetic and renin activity, resulting in either the absence of regression or even progression of LVH. Other classes of antihypertensive drugs nonuniformly change neural, humoral, or mechanical stimuli, so that the net effect ranges from full regression, partial regression, to none. Age and reactivity of sympathetic and/or renin activity may play a major role in determining the response of cardiac mass to BP lowering.