Abstract 6096: Long-Term Survival of Patients with Chest Pain Syndrome and Angiographically Normal or Near Normal Coronary Arteries: The Additional Prognostic Value of Coronary Flow Reserve
It has been demonstrated that in the low risk subset of patients with angiographically normal coronary arteries, 1 out of 10 shows wall motion abnormalities during dipyridamole echocardiography test (DET) and has a less benign prognostic outcome. Coronary flow reserve (CFR) on left anterior descending (LAD) artery can now be combined with wall motion analysis in the state-of-the art technique for DET.
Aim: To assess the prognostic value of CFR response in patients with normal coronary arteries and normal wall motion during stress. We selected 394 patients (171 males; 61±11 years) who underwent DET (0.84 mg/Kg over 6′) with 2D echo and CFR evaluation of LAD by Doppler. All had angiographically non-significant (<50% quantitatively assessed) stenosis in any major vessel, normal left ventricular function (wall motion score index=1) and test negativity for conventional wall motion criteria. Images were independently read by a core lab. Mean CFR was 2.5±0.6 and 87 (22%) patients had an abnormal CFR <2. During a median follow-up of 51 months, 31 events occurred: 4 deaths and 27 non-fatal myocardial infarctions (3 STEMI and 24 NSTEMI). Kaplan-Meier survival estimates showed a better outcome for those patients with normal CFR compared to those with a reduced CFR (see figure⇓). At multivariable analysis only an abnormal CFR (<2) was an independent predictor of hard events (HR=16.4, CI95%=6.7–40.2). In patients with angiographically normal or near-normal coronary arteries and preserved left ventricular function at baseline and during stress, CFR adds incremental value to the prognostic stratification achieved with clinical and angiographic data.