Coronary Flow Reserve in the Left Anterior and Posterior Descending Arteries as an Additional Option to Dipyridamole Stress Echocardiography for Detection of Stenosis

Abstract

to assess additive diagnostic value of simultaneous evaluation of coronary flow reserve (CFR) in the left anterior descending (LAD) artery and posterior descending artery (PDA) during dipyridamole stress echocardiography (stress-Echo) for detection of LAD and PDA stenoses >50%. 108 in-patients (mean age 50+/-11 years) with cardiac chest pain underwent dipyridamole stress-Echo with ECG-analysis, wall motion analysis by 2-dimentional imaging (2D) and coronary flow reserve (CFR) evaluation in both LAD and PDA by pulse-wave Doppler. The 2D test was considered positive when more or equal 2 segments demonstrated wall motion abnormalities. CFR was calculated as ratio of hyperemic to basal peak diastolic blood flow velocity. CFR <2.0 was considered reduced. Coronary angiography was performed within one week after stress-Echo. 34 of 97 patients with CFR in the LAD and wall motion in the LAD territory had LAD stenosis >50%, and 22 of 90 patients with evaluated CFR in the PDA and wall motion in the RCA territory had RCA stenosis >50%. Thus stenosis >50% was detected in 56 of 187 evaluated LAD and RCA. The 2D test and ECG results were positive for 35 arterial territories, reduced CFR - for 48 arteries. With combined evaluation of ECG, 2D test and CFR, accuracy was not significantly higher (80% for ECG+2D test, 82% for CFR and 80% for combined test) but sensitivity and negative predictive value increased (sensitivity: 63% for ECG+2D test, 86% for CFR and 91% for combined test; negative predictive value: 85% for ECG+2D test, 93% for CFR and 95% for combined test). Assessment of CFR in both LAD and PDA is feasible for majority of patients and can increase sensitivity and negative predictive value of dipyridamole stress-Echo for the detection.