Role of cardiac biomarkers (troponin I and CK-MB) as predictors of quality of life and long-term outcome after cardiac surgery

Perioperative and postoperative morbidity and mortality associated with cardiac surgery affect both the outcome and quality of life. Markers such as troponin effectively predict short-term outcome. In a prospective cohort study in a University Hospital we assessed the role of cardiac biomarkers, also as predictors of longterm outcome and life quality after cardiac surgery with a three-year follow-up after conventional heart surgery. Patients were interviewed via phone calls with a structured questionnaire examining general health, functional status, activities of daily living, perception of life quality and need for hospital readmission. Descriptive statistics and multivariate analysis were performed. Out of 252 consecutive patients, 8 (3.2%) died at the three years follow up: 7 for cardiac complications and 1 for cancer. Thirty-six patients (13.5%) had hospital readmission for cardiac causes (mostly for atrial fibrillation or other arrhythmias (9.3%), but none needed cardiac surgical reintervention; 21 patients (7.9%) were hospitalised for non-cardiac causes. No limitation in function activities of daily living was reported by most patients (94%), 92% perceived their general health as excellent, very good or good and none considered it insufficient; 80% were NYHA I, 17% NYHA II, 3% NYHA III and none NYHA IV. Multivariate analysis indicated preoperative treatment with digitalis or nitrates, and postoperative cardiac biomarkers release was independently associated to death. Elevated cardiac biomarker release and length of hospital stay were the only postoperative independent predictors of death in this study.