Prognostic value of troponin in infants with hypoplastic left heart syndrome between Stage I and II of palliation

BACKGROUND: The period between stage I and II procedure for treatment of hypoplastic left heart syndrome (HLHS) bears high mortality and morbidity. METHODS: We sought to analyze the prognostic value of Troponin T/I (Trop), a well-recognized marker for myocardial damage and heart failure, for predicting outcome in a retrospective analysis of 70 infants with HLHS at our institution between March 2001 and October 2014. RESULTS: Stage I procedure consisted of Norwood I operation in 35 (50%) and Hybrid-approach in 22 (31%) patients. Palliative care was chosen for 13 (19%) patients. Trop values were collected from clinical charts and were analyzed in relation to the overall outcome. Trop was significantly higher after Norwood I operation in comparison to Hybrid-approach (median 7.1 μg/l (0.7-20.9), vs 1.2 μg/l (0.3-17.9), P < 0.001). Overall mortality of treated patients was 39% (22 patients). Survival was 54% (19 patients) after Norwood and 73% (16 patients) after Hybrid-approach. Independently from the procedure used, maximal Trop and initial lactate values were significantly higher in non-survivors than in survivors, with median Trop of 9 μg/l (0.6-18.8) vs. 3.4 μg/l (0.4-20.9), P 0.007, and median lactate of 3.7 mmol/L (1.6-25) vs. 2.9 mmol/L (0.3-14.6), p 0.03. Reinterventions were required in 17 (30%) patients, 4 (11%) after Norwood and 13 (59%) after Hybrid procedure. No correlation was found between the need for reintervention and Trop levels in the interstage period. CONCLUSIONS: Patients with HLHS have significantly higher Trop levels after Norwood procedure than after Hybrid-approach. Maximal Trop values were related to mortality, but did not correlate with the need for reinterventions.