Myocardial damage influences short- and mid-term survival after valve surgery: a prospective multicenter study.

OBJECTIVE: Myocardial damage occurs after valve surgery, but its prognostic implication has not been evaluated. The aim of the present study was to assess the influence of myocardial damage on mortality and morbidity in patients undergoing aortic surgery (AVS) and mitral valve surgery (MVS).

METHODS: In a prospective multicenter study from the cardiac surgery registry of the Puglia region, cardiac troponin I (cTnI) was measured immediately after and the morning after the intervention in consecutive patients undergoing AVS or MVS. The percentile ranks of the cTnI peak values within each center were analyzed.

RESULTS: Of 965 patients (age, 67±12 years; 45.5% women), 579 had undergone AVS and 386 MVS. cTnI release was significantly greater in the MVS group than in the AVS group and in the nonsurvivors than in the survivors in both groups. The cTnI cutoff with the greatest sensitivity and specificity (60th percentile for AVS and 91st for MVS) in predicting hospital mortality (2.6%) was also associated with a greater rate of postoperative complications and mortality within 3 months postoperatively (multivariate hazard ratio, 3.38; P=.005). Compared with the reference model, which included the multivariate predictors of hospital mortality (active endocarditis, New York Heart Association class III-IV, left ventricular ejection fraction≤30%, and cardiopulmonary bypass duration), the addition of cTnI greater than the cutoffs showed significant improvement in model performance (likelihood ratio test, P=.009; net reclassification improvement, 0.751; P<.001; integrated discrimination improvement, 0.048; P=.002; c-index 0.832 vs 0.838).

CONCLUSIONS: An elevated postoperative cTnI level was an independent risk factor for mortality and morbidity. Measurement of the cTnI level improved the risk reclassification of patients undergoing AVS or MVS.