Pre-op Coronary CTA-FFRCT Evaluation OF Patients with no Cardiac History who are Undergoing Peripheral Vascular Surgery may Reduce the Risk Of Post-op MI/Death

Abstract

Introduction - Patients undergoing carotid, aortic or peripheral vascular surgery (PVS) have increased risk of post-op MI/death due to coexistent coronary artery disease, but the value of pre-op cardiac testing is uncertain. A new non-invasive diagnostic modality, coronary CT angiography (CTA) and computed fractional flow reserve (FFRCT), can reliably identify ischemia-producing coronary stenosis in stable chest pain patients (ref. 1,2,3) but its use for pre-op coronary risk assessment in PVS patients has not been reported. We performed pre-op CTA-FFRCT in patients with no cardiac history undergoing PVS in a prospective IRB-approved study and compared outcomes to a Registry of similar vascular patients with no cardiac history who underwent PVS during the preceding 18 months. Methods - Beginning Oct 2017, patients with no cardiac history and normal EKG admitted for elective PVS signed informed consent and underwent pre-op CTA -FFRCTevaluation with results available in <24 hours. Functionally significant coronary stenosis was defined as FFRCT ≤0.80 distal to a stenosis in one or more coronary arteries >2mm in diameter. CTA-FFRCTpatients were compared to Registry patients with respect to MACE (MI, acute coronary syndrome, stroke, death). Results - Coronary CTA was performed in 88 PVS patients with image quality suitable for FFRCTanalysis in 80 (91%) despite extensive coronary calcification (median calcium score 718, range 10-4135, 42% >1000). CTA-FFRCT patients (n=80) were no different from Registry (n=192) with regard to age (66±9 v. 67±8 years), gender (81% v. 82% male), cardiac risk factors, pre-op ABI or vascular surgical procedures performed. Most CTA-FFRCTpatients (55/80, 69%) had functionally significant coronary stenosis (FFRCT ≤0.80) with multivessel disease in 58% (Figure). Nonetheless, PVS was performed as scheduled in 74/80 (93%) with no post-op MI/death. PVS was postponed in 6 patients due to CTA-FFRCTresults: 2 had coronary angiography and coronary revascularization (stenting); 4 had medical therapy. At 30 days, MACE in CTA-FFRCTwas 0/80 (0%) compared to 10/192 (5.2%) in Registry (p=0.037). After 30 days, 24 CTA-FFRCTpatients underwent elective coronary angiography and coronary revascularization (20 with stents and 4 with CABG) with no complications or MACE events through 90 days. Longer term follow up is ongoing. Conclusion - Pre-op CTA-FFRCTreveals a high prevalence of unsuspected ischemia-producing coronary stenosis in the majority of patients with no cardiac history who undergo elective peripheral vascular surgery. Increased focus on peri-and post-operative cardiac care of vascular surgery patients with functionally significant coronary stenosis may reduce MI/mortality and improve survival.