Abstract 18417: Does Active Participation in Cardiac Rehabilitation Adversely or Favorably Affect BNP Levels in Post-Acute Myocardial Infarction Patients With Already Elevated Baseline BNP ?
Background: In post-acute myocardial infarction (AMI) patients, exercise-based cardiac rehabilitation (CR) has been reported to counteract left ventricular (LV) remodeling. However, in post-AMI patients with elevated B-type natriuretic peptide (BNP) levels at baseline, it is unclear whether active participation in CR leads to a decrease or further elevation of BNP levels. Accordingly, we studied determinants of sustained elevation of BNP in post-AMI patients with high baseline BNP levels.
Methods: We studied 293 consecutive AMI patients who had a high baseline BNP level (>=200pg/ml) and participated in our 3-month CR program. All patients underwent blood sampling and symptom-limited cardiopulmonary exercise testing (measurements for peak oxygen uptake [PVO2]) at the beginning and the end of the CR. Patients were divided into two groups according to the percent of changes in BNP levels (%ΔBNP) from the beginning to 3-month: Decreased (Dec) group (%ΔBNP<-10%, n=260) and Sustained-High (Sus) group (>=-10%, n=33).
Results: At baseline, Sus group, compared with Dec group, had higher prevalence of Killip classification>=2 (Sus 37 vs Dec 20%, P=0.04), lower LV ejection fraction (LVEF, 35±10 vs 41±10%, P=0.003) and larger LV systolic diameter (41±11 vs 38±8mm, P=0.04), whereas baseline PVO2 (17.9±3.8 vs 18.7±3.6ml/kg/min, NS) was similar. During CR, Sus group had lower training heart rate (TrHR, 93±14 vs 100±14bpm, P=0.03) than Dec group, while the number of ambulatory CR session attendance (14.7±8.1 vs 13.4±9.1, NS) was similar. After 3-month CR, BNP decreased in the whole patients, but it was significantly higher in Sus group than in Dec group (375 vs 133pg/mL, P<0.001) by definition. Notably, a significant inverse correlation was seen between %ΔBNP and increase in PVO2 (%ΔPVO2, P<0.001). Multiple regression analysis revealed that baseline BNP, LVEF, TrHR and %ΔPVO2 were the independent determinants of %ΔBNP.
Conclusion: In AMI patients with elevated BNP at baseline, lower LVEF, lower TrHR and lower improvement in PVO2 may predict sustained BNP elevation after CR. This result in turn suggests that active CR participation at a higher TrHR and a greater PVO2 improvement may be associated with a greater fall in initially elevated BNP.
Author Disclosures: A. Date: None. T. Tokeshi: None. R. Kumasaka: None. K. Nakao: None. T. Arakawa: None. S. Fukui: None. T. Hasegawa: None. M. Nakanishi: None. M. Yanase: None. T. Noguchi: None. S. Yasuda: None. H. Ogawa: None. Y. Goto: None.
- © 2016 by American Heart Association, Inc.