Coronary blood flow in renovascular hypertension

We assessed the acute effects of 2.5 mg oral cilazapril on systemic and coronary hemodynamics in seven renovascular hypertensive patients with a chronically overactive renin-angiotensin system (RAS), but with no electrocardiographic or echocardiographic signs of left ventricular hypertrophy. Cilazapril resulted in a significant decrease in mean arterial pressure and coronary vascular resistance, together with a prolonged increase in coronary sinus blood flow (CSBF). Post-cilazapril handgrip resulted in larger increases in CSBF in response to a given increase in myocardial oxygen requirements. It is concluded that the chronic activation of the RAS exerts an adverse influence on the control mechanisms of CSBF and that converting enzyme inhibition reverses the effects of angiotensin II on coronary hemodynamics. Converting enzyme inhibitors may have a cardioprotective role in renovascular hypertension.