Abstract
Reductions in blood pressure (BP) through intervention can significantly reduce the risk of cardiovascular events in hypertensive patients. However, a number of trials indicate that beta-blockers, despite lowering BP, do not reduce the risk of stroke.
A recent meta-analysis suggested that, over and beyond BP reduction, angiotensin-converting enzyme (ACE) inhibitors appear superior to calcium channel blockers for prevention of coronary heart disease whereas calcium channel blockers appear superior to ACE inhibitors for prevention of stroke.
Indeed, in the Syst-EUR study a 42% reduction in strokes was achieved in the calcium antagonist arm when compared to the placebo arm.It is hypothesised that antihypertensive agents that stimulate the AT2-receptor (thiazide diuretics, dihydropyridine calcium antagonists and angiotensin receptor blockers) are more cerebroprotective than drug classes that do not stimulate the AT2-receptor (beta-blockers and ACE inhibitors).The angiotensin receptor blockers are the only drug class that have a dual mechanism of action that could be helpful in preventing strokes in that they not only inhibit the AT1-receptor but also allow stimulation of the AT2-receptor. Not surprisingly therefore, in trials such as LIFE, VALUE and MOSES, angiotensin receptor blockers showed excellent cerebroprotection.