Prognostic value of Doppler echocardiographic-derived coronary flow velocity reserve of left anterior descending artery in octogenarians with stress echocardiography negative for wall motion criteria

Doppler-derived coronary flow velocity reserve (CFVR) of left anterior descending (LAD) artery is an effective tool to predict overall mortality. The aim was to investigate the capability of CFVR to predict outcome in an unselected cohort of patients older than 80 years having stress echo negative by wall motion criteria. The study group refers to 369 patients aged > 80 years (156 men; mean age 83 ± 2 years) who had undergone dipyridamole stress echocardiography with CFVR assessment of LAD artery of known (n = 144) or suspected (n = 225) coronary artery disease. Stress echocardiography was negative for wall motion criteria in all cases. Mean CFVR was 2.07 ± 0.53. During a median follow-up of 21 months, there were 62 major adverse cardiac events (MACEs; 45 deaths and 17 non-fatal myocardial infarctions). With a receiver operating characteristic analysis, a CFVR of ≤ 1.93 was the best cut-off for predicting mortality and MACE. At individual patient analysis, 152 (41%) subjects had a CFVR of < 1.93. Annual mortality was 9.8% in patients with CFVR 1.93 (P = 0.001); an annual MACE rate was 14.8% in the former and 4.5% in the latter (P < 0.0001). Of 15 clinical and echocardiographic parameters analysed, CFVR ≤ 1.93 [hazard ratio (HR) = 2.17, 95% CI 1.14-4.10] and resting wall motion abnormality (RWMA; HR = 2.60; 95% CI 1.35-5.00) were multivariable indicators of mortality. Moreover, CFVR ≤ 1.93 (HR = 2.69, 95% CI 1.56-4.67), and RWMA (HR = 2.38; 95% CI 1.31-4.33) were also strong independent predictors of MACEs. At incremental analysis, CFR ≤ 1.93 added prognostic information over clinical evaluation and RWMA when both mortality and MACE were taken as clinical end points. A reduced CFVR of LAD artery is a strong and independent indicator of both mortality and MACE, adding prognostic information over clinical evaluation and RWMA. Conversely, a preserved CFVR predicts a favourable outcome particularly in subjects with no RWMA.