Doppler flow velocity profile of poststenotic coronary blood flow under isosorbide dinitrate

Nitrates are commonly used in anti-anginal therapy of coronary heart disease. They endorse coronary vasodilation and alter poststenotic coronary blood flow. In this study the authors investigate the feasibility of Doppler flow assessment of poststenotic coronary blood flow profile and changes due to isosorbide dinitrate. Poststenotic coronary blood flow was investigated in 26 patients with severe single stenosis in one vessel (left anterior descending=14, left circumflex=7, right coronary artery=5) using the combined measurement of cross sectional area by quantitative coronary angiography and infracoronary Doppler time-averaged peak velocity prior to and following intracoronary application of 0.5 mg isosorbide dinitrate. Isosorbide dinitrate demonstrated no significant change in poststenotic intracoronary Doppler flow velocity parameters. Corresponding poststenotic coronary artery diameter increased significantly from 2.55/spl plusmn/0.54 to 2.94/spl plusmn/0.66 mm (p<0.001). Intracoronary nitrates improved poststenotic coronary blood flow highly significantly from 28/spl plusmn/21 to 40/spl plusmn/30 ml/min (p<0.001). 17 of the 26 lesions (65%) demonstrated an increase>20% following isosorbide dinitrate ic. The combined implementation of quantitative coronary arteriography and intracoronary Doppler flow velocity measurement offers the potential for the evaluation of poststenotic coronary artery blood flow, isosorbide dinitrate increased poststenotic coronary blood flow in most cases of coronary artery disease and parallels increment of coronary artery diameter.