Objective: To investigate the ability of cardiac troponin I (cTnI) to predict functional recovery and left ventricular remodelling following primary percutaneous coronary intervention (pPCI) in ST-elevation myocardial infarction (STEMI).
Design: Post hoc study extending from randomised controlled trial.
Patients: 132 patients with STEMI receiving pPCI.
Main outcome measures: Left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volume index (EDVI and ESVI) and changes in these parameters from day 5 to 4 months after the index event.
Methods: Cardiac magnetic resonance examination performed at 5 days and 4 months for evaluation of LVEF, EDVI and ESVI. cTnI was sampled at 24 and 48 h.
Results: In linear regression models adjusted for early (5 days) assessment of LVEF, ESVI and EDVI, single-point cTnI at either 24 or 48 h were independent and strong predictors of changes in LVEF (p<0.01), EDVI (p<0.01) and ESVI (p<0.01) during the follow-up period. In a logistic regression analysis for prediction of an LVEF below 40% at 4 months, single-point cTnI significantly improved the prognostic strength of the model (area under the curve = 0.94, p<0.01) in comparison with the combination of clinical variables and LVEF at 5 days.
Conclusion: Single-point sampling of cTnI after pPCI for STEMI provides important prognostic information on the time-dependent evolution of left ventricular function and volumes.
Trial registration: ClinicalTrials.gov NCT00326976.