Obese patients with HF have decreased generation of BNP
NATIONAL HARBOR, Md. — Researchers for a new study identified an inverse association between production of coronary sinus brain natriuretic peptide and BMI.
“The inverse relationship between BMI and brain natriuretic peptide has been demonstrated in diverse clinical settings. The question we’re trying to answer is: What the reason is for this inverse relationship between brain natriuretic peptide and BMI? Is this a problem of brain natriuretic peptide generation or because of increased … clearance?” Zubair Shah, MBBS, cardiology fellow at University of Kansas Medical Center, said during a Jay N. Cohn New Investigator Award session.
Shah and colleagues measured coronary sinus brain natriuretic peptide (BNP), venous BNP and arterial BNP in 51 patients with HF with reduced systolic function scheduled for implantation with a device for cardiac resynchronization therapy. The three BNP measurements were performed during index CRT within 15 minutes of one another. Coronary sinus BNP served as a surrogate for BNP production in the analysis, and change to coronary sinus BNP was used as a surrogate for BNP metabolism.
The mean age of the cohort was 64 years, 86.2% were white and 60.7% were men. Patients were divided into two groups based on BMI: < 30 kg/m2 (n = 29) or > 30 kg/m2 (n = 22).
According to results presented, the mean coronary sinus BNP level was 350.71, which was significantly higher than mean levels of arterial BNP (199.64) and venous BNP (179.8). Shah said this finding is encouraging, as it indicates that coronary sinus BNP is close to the BNP source.
Between the groups, those with lower BMI had higher levels of coronary sinus BNP (417.5 vs. 286.2), arterial BNP (242 vs. 151.9) and venous BNP (228 vs. 126.6). Results of Spearman rank correlation analysis indicated a significant inverse relationship between coronary sinus BNP levels and BMI (P = .04), but not between change to BNP and BMI (P = .66).
BMI was an independent predictor of coronary sinus BNP, but not change to BNP, according to multivariate linear regression analysis.
“Since coronary sinus brain natriuretic peptide is considered a surrogate of brain natriuretic peptide generation, our findings indicate that the underlying mechanism for lower brain natriuretic peptide levels in patients with higher BMI is [reduced] generation of brain natriuretic peptide rather than increased peripheral metabolism,” Shah said. – by Adam Taliercio
Shah Z, et al. Jay N. Cohn New Investigator Physiology/Clinical Award. Presented at: Heart Failure Society of America Annual Scientific Meeting; Sept. 26-29, 2015; National Harbor, Md.
Disclosure: Shah reports no relevant financial disclosures.