Abstract 17498: Intensified Vasodilating Treatment Improves Maximum Coronary Perfusion and Flow Reserve in Patients Treated for Essential Hypertension
Background: Microvascular impairment in essential hypertension leads to a generalized increase in minimum vascular resistance and a reduced vasodilator capacity. In the heart, the coronary flow reserve (CFR) is reduced which may lead to microvascular angina and eventually to hypertensive heart failure. The present study was performed to determine if intensified vasodilating treatment regimen could improve forearm- and coronary minimum vascular resistance and CFR in already well-treated patients with essential hypertension.
Methods: Forty-eight patients receiving unaltered antihypertensive treatment for minimum 3 months were given vasodilating treatment regimen added to their current treatment (using ramipril, amlodipine, losartan, and/or lercanidipin as appropriate). Measures of CFR, coronary flow and left ventricular mass index (LVMI) were obtained with echocardiography. Cardiac output and systemic vascular resistance index (SVRI) were determined using an inert gas rebreathing method and forearm minimum vascular resistance was obtained with venous occlusion plethysmography. Maximum coronary flow was induced using adenosine.
Results: BP at baseline was 131.5±1.4/80.8±0.9 mmHg. Following 6 months of intensified vasodilating treatment, 24-h mean ambulatory blood pressure was reduced by 5.5±0.7% (p<0.001) while CFR increased by 19.7±2.0% (p<0.001) and coronary minimum vascular resistance decreased by 22.6±4.3% (p<0.001). Maximum coronary flow was increased by 7.2±2.1% (p=0.001). Cardiac output and minimum forearm vascular resistance were unaltered following treatment. Multivariate analysis showed that patients with the highest drop in SVRI (ΔSVRI > 5.7%) had a significantly (p = 0.02) higher increase in CFR (23.0±2.7%) compared to patients with a smaller drop in SVRI (ΔSVRI < 5.7%) (CFR 13.6±2.7%) when data were adjusted for change in blood pressure. No serious side-effects were noted.
Conclusion: Add-on of vasodilating treatment improved maximum coronary perfusion and flow reserve in patients already treated for EH to a degree that could not be predicted from the change in blood pressure. Decrease in coronary flow reserve was associated with reduction in systemic vascular resistance.
- © 2012 by American Heart Association, Inc.