In numerous studies left ventricular hypertrophy has been clearly established to be a strong, blood-pressure independent risk factor for cardiovascular morbidity and mortality. In fact, increased echocardiographic left ventricular mass has been shown to predict cardiovascular complications not only in patients with hypertension, but also in the general population. Preliminary data revealed that regression of left ventricular hypertrophy indeed reduces cardiovascular complications. As a consequence, regression of left ventricular hypertrophy by drug treatment has emerged as a desirable goal in patients with echocardiographically determined left ventricular hypertrophy. These findings raised the question, whether certain antihypertensive drugs differ in their ability to reduce left ventricular mass. To resolve this issue several comparative studies and some meta-analyses have been carried out. In a meta-analysis by Dahlöf et al., comprising 109 treatment studies published until december 1990 with a total of 2357 patients, ACE-inhibitors (-15%) were most effective in reducing left ventricular mass followed by diuretics (-11.3%), calcium channel blockers (-8.5%) and beta-blockers (-8%). Reduction in left ventricular mass was mainly due to a decrease in wall thickness except for diuretics which predominantly reduced ventricular diameter. Although reduction in blood pressure was similar for all antihypertensive agents, the correlation between changes in mean arterial pressure and effect on left ventricular mass was only significant for beta-blockers with a modest correlation for ACE-inhibitors and no clearcut relation for diuretics and calcium channel blockers.