Ischemia targeted coronary revascularization improves 5-year survival following carotid endarterectomy

OBJECTIVES: Long-term survival after carotid endarterectomy (CEA) is limited by adverse cardiac events with 5% annual mortality. We sought to determine whether diagnosis of silent coronary ischemia together with elective ischemia-targeted coronary revascularization can reduce death and myocardial infarction (MI) and improve long-term survival of patients after CEA.

METHODS: Observational cohort study of patients with no cardiac history or coronary symptoms undergoing elective CEA. Patients enrolled in a prospective study of preoperative cardiac evaluation using coronary computed tomography-derived fractional flow reserve (FFRCT) to detect silent (asymptomatic) coronary ischemia together with elective postoperative ischemia-targeted coronary revascularization were compared with matched controls with standard preoperative cardiac evaluation and no elective coronary revascularization. Lesion-specific coronary ischemia was defined as an FFRCT of ≤0.80 distal to >30% stenosis with severe ischemia defined as an FFRCT of ≤0.75. End points included all-cause death, cardiac death, MI, stroke, and major adverse cardiovascular events (MACE) (defined as cardiovascular death, MI, or stroke) during 5 years of follow-up.

RESULTS: FFRCT (n = 100) and control (n = 100) cohorts were well-matched with no significant differences in age, gender, comorbidities, or indications for CEA. Asymptomatic lesion-specific coronary ischemia (FFRCT of ≤0.80) was present in 57% of FFRCT patients, with severe ischemia in 44% and left main ischemia in 7%; 43% had no coronary ischemia (FFRCT of >0.80). The status of coronary ischemia was unknown in the controls. CEA was performed successfully in both cohorts with no deaths or neurological events, and all patients received optimal postoperative medical therapy. Elective ischemia-targeted coronary revascularization was performed in 33% of FFRCT patients within 3 months of CEA. Controls had no elective coronary revascularization. During 5 years of follow-up, compared with controls, the FFRCT group had fewer all-cause deaths (11% vs 24%; hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.17-0.77; P = .016); fewer cardiac deaths (3% vs 13%; HR, 0.15; 95% CI, 0.03-0.69; P = .009); fewer MIs (3% vs 21%; HR, 0.07; 95% CI, 0.02-0.31; P < .001), and fewer MACEs (10% vs 33%; HR, 0.21; 95% CI, 0.10-0.44; P < .001) with no differences in stroke. There were no cardiac deaths or MIs among patients with no coronary ischemia (FFRCT of >0.80). Annual mortality in FFRCT was 2.2% per year compared with 4.8% per year in controls.

CONCLUSIONS: Diagnosis of silent coronary ischemia together with elective ischemia-targeted coronary revascularization after CEA decrease the 5-year risk of all-cause death, cardiac death, MI, and MACE by >50% and improved survival (89%) compared with patients receiving standard cardiac evaluation and care (76%).