Diagnosis and Treatment of Ischemia-Producing Coronary Stenoses Improves 5-year Survival of Patients Undergoing Major Vascular Surgery.

BACKGROUND: Patients undergoing vascular surgery procedures have poor long-term survival due to coexisting coronary artery disease (CAD) which is often asymptomatic, undiagnosed and undertreated. We sought to determine whether pre-operative diagnosis of asymptomatic (silent) coronary ischemia using coronary CT -derived fractional flow reserve (FFRCT ) together with post-operative ischemia-targeted coronary revascularization can reduce adverse cardiac events and improve long-term survival following major vascular surgery.

METHODS: In this observational cohort study of 522 patients with no known CAD undergoing elective carotid, peripheral or aneurysm surgery we compared two groups of patients. Group I: 288 patients enrolled in a prospective IRB-approved study of pre-operative coronary CTA and FFRCT testing to detect silent coronary ischemia with selective post-operative coronary revascularization in addition to best medical therapy (BMT) (FFRCT guided) and Group II: 234 matched controls with standard pre-operative cardiac evaluation and post-operative BMT alone with no elective coronary revascularization (Usual Care). In the FFRCT group lesion-specific coronary ischemia was defined as FFRCT ≤0.80 distal to a coronary stenosis, with severe ischemia defined as FFRCT ≤0.75. Results were available for patient management decisions. Endpoints included all-cause death, cardiovascular (CV) death, myocardial infarction (MI) and MACE (major adverse cardiovascular events = death, MI or stroke) during 5-year follow up.

RESULTS: The two groups were similar in age, gender, and comorbidities. In FFRCT , 65% of patients had asymptomatic lesion-specific coronary ischemia, with severe ischemia in 52%, multivessel ischemia in 36% and left main ischemia in 8%. The status of coronary ischemia was unknown in Usual Care. Vascular surgery was performed as planned in both cohorts with no difference in 30-day mortality. In FFRCT , elective ischemia-targeted coronary revascularization was performed in 103 patients 1-3 months following surgery. Usual Care had no elective post-operative coronary revascularizations. At five years, compared to Usual Care, FFRCT guided had fewer all-cause deaths (16% vs 36%, HR 0.37, 95% CI 0.22-0.60, P<.001), fewer cardiovascular deaths (4% vs 21%, HR 0.11, 95% CI 0.04-0.33, P<.001), fewer myocardial infarctions (4% vs 24%, HR 0.13, 95% CI 0.05-0.33, P<.001) and fewer MACE events (20% vs 47%, HR 0.36, 95% CI 0.23-0.56, P<.001). Five-year survival was 84% in FFRCT compared to 64% in Usual Care (p<.001).

CONCLUSIONS: Diagnosis of silent coronary ischemia with ischemia-targeted coronary revascularization in addition to BMT following major vascular surgery was associated with fewer adverse cardiovascular events and improved 5-year survival compared patients treated with BMT alone as per current guidelines.