Effect of candesartan on coronary flow reserve in patients with systemic hypertension

BACKGROUND: Patients with hypertension have structural and functional changes in conductance and resistance vessels. In the absence of coronary stenosis the coronary microvascular function can be analysed by studying the coronary reserve. The aim of this study was to evaluate, non-invasively, the effect of candesartan on coronary microvascular function in hypertensive patients. METHODS: Twenty-two hypertensive patients (> 40 years) without clinical coronary disease (age 63.86 +/- 10.3 years; women, 59.1%) were studied. In addition to blood pressure (BP), measurement of carotid intima-medial thickness (IMT), left ventricle mass index (LVMI) and the coronary flow reserve (CFR) were evaluated with echography at the beginning, and after 3 months of treatment with 16 mg/day of candesartan. Twelve hypertensive controls (64.50 +/- 10.8 years; women, 58.4%) completed the same study without any change in treatment. RESULTS: A 15% improvement in CFR (3.10 +/- 1.02 to 3.56 +/- 1.06; P = 0.001) was observed simultaneously with the BP reduction. There was no change in CFR in the control group (2.9 +/- 1.1 to 3.01 +/- 0.9; P = 0.23). The IMT was not modified significantly at the end of the follow-up (0.86 +/- 0.1 to 0.83 +/- 0.1 mm; P = 0.103). CONCLUSION: Candesartan improves the CFR in hypertensive patients. The improvement was not related to BP control or LVMI regression. Patients with a lower CFR show a better response to candesartan. This fact can be demonstrated non-invasively with echography after 3 months of therapy.