Long-term prognostic value of asymptomatic cardiac troponin T elevations in patients after major vascular surgery

Abstract

Conclusion: An elevated perioperative cardiac troponin T (cTn-T) concentration after major vascular surgery is associated with increased all-cause mortality. Summary: cTnT is both specific and sensitive for myocardial injury. Elevations in cTn-T concentration without persistent or new electrocardiographic (ECG) abnormalities and no clinical evidence of ischemia are common after major vascular surgery. The authors sought to examine the long-term prognostic value of elevated cTn-T levels in patients after major vascular surgery. Between 1996 and 2000, 393 patients who underwent successful aortic or infrainguinal vascular surgery and in whom cTn-T was routinely sampled were followed up until May 2003 (median, 4 years) for all-cause mortality. During this period total creatinine kinase; creatine kinase, myocardial bound; and cTn-T were routinely screened in all patients on postoperative days 2, 3, and 7. Patients with suspected myocardial ischemia were also evaluated with ECG. Elevated cTn-T level was defined as serum concentration >0.1ng/mL in any sample. Eighty patients (20%) died during follow-up. The all-cause mortality rate was significantly higher in patients with elevated cTn-T levels compared with patients with normal cTn-T levels (41% vs 17%; P < .001). This association between elevated cTn-T level and increased all-cause mortality (hazard ratio, 1.9; 95% confidence interval, 1.1-3.1) was independent of baseline clinical characteristics. Elevated cTn-T levels had significant prognostic value in patients with and without renal dysfunction, in patients with transient ECG abnormalities, and in those with abnormal levels of creatine kinase, myocardial bound. Comment: It is difficult to know how to apply these data clinically. The adverse prognosis imparted by elevated cTn-T levels does not become known until after the patient has undergone the surgical procedure. The findings are interesting, but do not argue for routine screening for elevated troponin levels in patients without symptoms.