NT-proBNP to guide risk stratification after cardiac rehabilitation in patients with ST-segment elevation myocardial infarction.

Introduction and objectives: The use of N-terminal pro-brain natriuretic peptide (NT-proBNP) after ST-segment elevation acute myocardial infarction (STEMI) is unclear. We evaluated its prognostic significance after post-STEMI cardiac rehabilitation.

Methods: The prognostic significance of NT-proBNP was tested upon completion of cardiac rehabilitation (median, 45 days post-STEMI) in an exploratory group (n = 105 patients with the researchers blinded to NT-proBNP values) and validated in the following 276 patients. Baseline and cardiac imaging variables including cardiovascular magnetic resonance (CMR) parameters were recorded. The primary endpoint was the occurrence of a first major adverse cardiac event (MACE: cardiac death, myocardial infarction, or re-admission for heart failure).

Results: In the exploratory group, a cut-off value of NT-proBNP >400 pg/mL emerged as a potent MACE predictor (37 % vs.17 %; hazard ratio [HR]: 6.8 [1.5-30.3], p = 0.01). In the study group, during a 203-week median follow-up, 88 (32 %) first MACEs were detected. NT-proBNP >400 pg/mL (n = 168, 61 %) associated with a higher MACE rate (46 % vs. 10 %, HR: 4.6 [2.3-8.9], p < 0.001) and, separately, with more cardiac deaths, myocardial infarctions, and re-admissions for heart failure (p < 0.05 for all comparisons). NT-proBNP improved the multivariate model for MACE prediction (area under the curve 0.81 vs. 0.72, p < 0.001). Analyzing all measurements performed during follow-up (n = 1018), the risk of transition to MACE was higher in case of NT-proBNP >400 pg/mL (14 % vs.3 %, p < 0.001).

Conclusions: Even after comprehensive adjustment, NT-proBNP emerges as a potent, accessible and inexpensive tool for risk stratification of STEMI patients after completion of rehabilitation programs.