Abstract
Background The survival benefit of revascularization of chronic total occlusion (CTO) of the coronary arteries remains a subject of controversy. We measured high sensitivity troponin-I (hsTn-I) levels as an estimate of myocardial ischemia in patients with stable coronary artery disease, with the hypothesis that (1) patients with CTO have higher levels of hsTn-I than patients without CTO, (2) hsTn-I levels will predict adverse cardiovascular events in patients with CTO, and (3) patients with elevated hsTn-I levels will have a survival benefit from CTO revascularization. Methods and Results In 428 patients with stable coronary artery disease and CTO undergoing coronary angiography, adverse event rates were investigated. Cox proportional hazards models and Fine and Gray subdistribution hazard models were performed to determine the association between hsTn-I level and incident event rates in patients with CTO. HsTn-I levels were higher in patients with compared with those without CTO (median 6.7 versus 5.6 ng/L, P=0.002). An elevated hsTn-I level was associated with higher adverse event rates (adjusted all-cause mortality hazard ratio, 1.19 [95% CI, 1.08-1.32]; P=0.030) for every doubling of hsTn-I level. CTO revascularization was performed in 28.3% of patients. In patients with a high (>median) hsTn-I level, CTO revascularization was associated with substantially lower all-cause mortality (adjusted hazard ratio, 0.26 [95% CI, 0.08-0.88]; P=0.030) compared with those who did not undergo revascularization. In patients with a low (