Increased perioperative b-type natriuretic peptide associates with heart failure hospitalization or heart failure death after coronary artery bypass graft surgery

Abstract

Background: Heart failure (HF) is a leading cause of hospitalization and mortality. Plasma B-type natriuretic peptide (BNP) is an established diagnostic and prognostic ambulatory HF biomarker. We hypothesized that increased perioperative BNP independently associates with HF hospitalization or HF death up to 5 yr after coronary artery bypass graft surgery.

Methods: The authors conducted a two-institution, prospective, observational study of 1,025 subjects (mean age = 64 ± 10 yr SD) undergoing isolated primary coronary artery bypass graft surgery with cardiopulmonary bypass. Plasma BNP was measured preoperatively and on postoperative days 1-5. The study outcome was hospitalization or death from HF, with HF events confirmed by reviewing hospital and death records. Cox proportional hazards analyses were performed with multivariable adjustments for clinical risk factors. Preoperative and peak postoperative BNP were added to the multivariable clinical model in order to assess additional predictive benefit.

Results: One hundred five subjects experienced an HF event (median time to first event = 1.1 yr). Median follow-up for subjects who did not have an HF event = 4.2 yr. When individually added to the multivariable clinical model, higher preoperative and peak postoperative BNP concentrations each, independently associated with the HF outcome (log10 preoperative BNP hazard ratio = 1.93; 95% CI, 1.30-2.88; P = 0.001; log10 peak postoperative BNP hazard ratio = 3.38; 95% CI, 1.45-7.65; P = 0.003).

Conclusions: Increased perioperative BNP concentrations independently associate with HF hospitalization or HF death during the 5 yr after primary coronary artery bypass graft surgery. Clinical trials may be warranted to assess whether medical management focused on reducing preoperative and longitudinal postoperative BNP concentrations associates with decreased HF after coronary artery bypass graft surgery.

Figures

Fig. 1

Box and whisker plots of preoperative and peak postoperative plasma B-type natriuretic peptide (BNP) concentrations for 1,025 subjects undergoing primary coronary artery bypass graft surgery. BNP concentrations are stratified by the group of 920 subjects who did not experience heart failure (HF) events and the group of 105 subjects who did experience HF events during 5-yr postoperative follow-up. The 10th (lower whisker), 25th (lower box end), 50th (middle line), 75th (upper box end), and 90th (upper whisker) percentile BNP values are shown for each group for both the preoperative and peak postoperative (postoperative days 1–5) assessments. *P < 0.001 HF event compared with the no-HF event group at that perioperative time point.

Fig. 2

Kaplan–Meier survival curves for 1,025 primary coronary artery bypass graft (CABG) surgical patients followed up to 5 yr after surgery. Curves are stratified according to the top versus bottom three quartiles of (A) preoperative B-type natriuretic peptide (BNP) concentrations and (B) the peak of postoperative day 1–5 BNP concentrations. Curves signified by dotted lines signify 95% CIs for heart failure (HF) event-free survival estimates during 5 yr of postoperative follow-up.