The incidence of supraventricular and ventricular arrhythmias in patients with arterial hypertension is up to 96% and is about 10 times higher than in normotensives. Predictors for an increased ventricular arrhythmogenic risk are left ventricular hypertrophy (LVH), impaired left ventricular function with enlarged end diastolic and end diastolic volumes as well as late potentials which in case of LVH increase from a 7% to 18% incidence. Especially the Simson criteria fQRS and RMS seem to characterize patients at risk. In addition a longer duration of hypertension in conjunction with a higher muscle mass index and a larger amount of couplets and non-sustained ventricular tachycardias, documented by Holter recording, are determinants of life threatening arrhythmias. In addition, an increased ventricular vulnerability in electrophysiological study significantly depends on left ventricular hypertrophy. Regression of LVH goes along with a decreased rate of ventricular extrasystoles. We therefore hypothesize that by pharmacological regression of hypertrophy the prevalence of complex arrhythmias decreases.