P4984The functional and coronary anatomic correlates of coronary flow velocity reserve during stress echocardiography

Abstract

Abstract Background The assessment of coronary flow velocity reserve (CFVR) on left anterior descending coronary artery (LAD) expands the risk stratification potential of stress echocardiography (SE) based on regional wall motion abnormalities (RWMA). Aim To assess the feasibility and functional correlates of CFVR. Methods In a prospective, observational, multicenter study, we initially screened 3,410 patients (2061, 60%, male; age 63±11 years; ejection fraction, EF=61±9%) with known or suspected coronary artery disease (CAD) and/or heart failure (HF). All patients underwent SE (exercise, n=1288; vasodilator, n=1860; dobutamine, n=262) based on RWMA in 20 accredited laboratories of 8 countries. CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed-Doppler assessment of LAD flow. We also assessed B-lines (a sign of pulmonary congestion) with lung ultrasound and left ventricular contractile reserve (LVCR) based on Force (systolic blood pressure/end-systolic volume). Results The success rate for CFVR on LAD was 3,002/3,410 (feasibility=88%): 1,025/1,288 for exercise (80%), 1,766/1,860 (95%) for vasodilator (dipyridamole, n=1,841 and adenosine= 18) and 211/262 (81%) for dobutamine (p<0.001 vs vasodilator, p=NS vs exercise). Imaging time was <3 min and analysis time <1 min per patient. Reduced (≤2.0) CFVR was found in 896/3,002 (30%) patients. At multivariate logistic regression analysis, age (odds ratio, OR: 1.025, 95% Confidence intervals, CI: 1.015–1.036, p<0.001), diabetes (OR: 2.271, 95% CI: 1.218–4.235, p=0.10), RWMA (OR: 6.550, 95% CI: 4.989–8.599, p<0.01), abnormal LVCR (OR: 3.446, 95% CI: 2.774–4.281, p<0.01) and stress-rest B-lines change (OR: 1.519, 95% CI: 1.174–1.99, p=0.01) were associated with reduced CFVR. In the 1149 patients with coronary angiographic information, a reduced CFVR was present in 103/455 patients (23%) with no CAD, 119/432 (27%) with 1-, 72/167 (43%) with 2-, and 62/95 (65%) with 3-vessel disease (p<0.001 by ANOVA for trend). Figure 1 Conclusions CFVR is feasible with all SE protocols. The reduced CFVR is often accompanied by RWMA, abnormal LVCR and pulmonary congestion during stress.