Abstract 12512: Changes in B-type Natriuretic Peptide and Reverse Left Ventricular Remodeling After Restrictive Annuloplasty in Patients with Advanced Cardiomyopathy
Background: Restrictive mitral annuloplasty (RMA) can reverse left ventricular (LV) remodeling and reduces plasma B-type natriuretic peptide (BNP), a surrogate biomarker for heart failure, in patients with advanced cardiomyopathy and functional mitral regurgitation. However, the relationship between the reverse LV remodeling after RMA and changes in plasma BNP over time remains poorly defined.
Methods: Thirty-six patients with ischemic cardiomyopathy (ejection fraction <40%) underwent 64-row multidetector computed tomography (MDCT) before and 1.7±1.6 months after RMA. All patients underwent stringent downsizing annuloplasty. Three-dimensional MDCT images were used to calculate LV end-diastolic volume index (EDVI), and end-systolic volume index (ESVI), LV ejection fraction, and regional and global end-systolic wall stress (ESS). Blood samples for plasma BNP measurement was collected at the day of MDCT examination.
Results: After RMA, LVEDVI and LVESVI decreased from 143±33 to 116±40 ml/m2 and from 110±35 to 79±37 ml/m2 (p<0.0001 for both), respectively. Global ESS decreased from 263±40 to 202±41 kdynes/cm2, and LV ejection fraction improved from 24±9 to 34±12% (p<0.0001 for both). Plasma BNP decreased from 787±640 to 330±446 pg/ml (p<0.0001). There were significant correlations between change in LVEDVI and LVESVI (r=0.90, p<0.0001), and change in LVESVI and global ESS (r=0.58, p=0.0002), and change in global ESS and LV ejection fraction (r=-0.52, p=0.001). Moreover, the percent change in plasma BNP level significantly correlated with the magnitude of changes in the LVEDVI (r=0.33, p=0.047), LVESVI (r=0.48, p=0.003), LV ejection fraction (r=0.51, p=0.002), and global ESS (r=0.58, p=0.0002), respectively. Multivariate regression analysis showed that the percent change in the plasma BNP was only significantly associated with change in the global ESS (standardized partial regression coefficient=0.41, p=0.03), while not in the LVEDVI, ESVI, or LVEF.
Conclusions: Changes in BNP over time after RMA were associated with postoperative reverse LV remodeling process, particularly corresponding changes in LV wall stress. Whether this favorable neurohormonal response is predictive of an improved survival requires further evaluation.
- © 2012 by American Heart Association, Inc.