It has been previously demonstrated that coronary vascular reserve (CVR) was severely impaired in hypertensive patients with left ventricular hypertrophy (LVH), even after anti-hypertensive therapy. To assess if CVR was similarly depressed in hypertensive patients without LVH, peak-to-resting coronary flow velocity ratio (P/R) and a minimal coronary vascular resistance index (MCVRI) were determined with a coronary Doppler catheter placed into the left anterior descending coronary artery and maximally vasodilating dose of intracoronary papaverine (12 mg) in 16 control subjects (C), 7 untreated hypertensives without LVH (G1), and 7 hypertensives without LVH treated for at least one year (G2). All subjects and patients had normal left ventricular angiography and coronary arteriography. Left ventricular and aortic pressures, rate-pressure-product (RPP) were significantly elevated in G1 and were similar to those of control subjects in G2. Results evidenced that P/R was reduced and that MCVRI was increased in G1. However, these alterations were moderate. In G2, these two indices were similar to those of control subjects: [table: see text]
Conclusions: These results suggest: 1) that alterations of coronary microcirculation occur before left ventricular hypertrophy in hypertensive patients; 2) that anti-hypertensive therapy may restore a normal coronary vascular reserve in hypertensive patients without LVH, when coronary vascular reserve remained severely impaired despite normalization of arterial pressure in patients with persistent LVH.