Left Atrial Remodeling Related to Disproportionately Low B-Type Natriuretic Peptide in Acute Heart Failure Patients with Atrial Fibrillation

Abstract

The diagnostic performance of B-type natriuretic peptide (BNP) for acute heart failure (HF) is impaired in patients with atrial fibrillation (AF). Increased AF burden in HF is associated with left atrial (LA) remodeling. Recent studies have revealed that LA remodeling may affect LV filling. We hypothesized that LA remodeling affects BNP secretion in acute HF conditions. The study investigated the clinical impact of LA remodeling on admission BNP levels in acute HF patients with and without AF. Consecutive acute HF hospitalized patients (n = 899) were divided into groups with (n = 382) or without AF (n = 507) and subdivided into disproportionately low BNP (LB) (≤200 pg/ml), medium BNP (200 to 600 pg/ml) and high BNP (≥600 pg/ml) subgroups. The AF group had a higher proportion of patients with LB than the non-AF group (23.6% vs 16.6%, p = 0.009). BNP levels in both groups were positively correlated with LV end-diastolic volume and negatively correlated with LV ejection fraction in both groups. In contrast, BNP was positively correlated with LA volume index in the non-AF group, but negatively correlated in the AF group. The survival rates were significantly higher in the LB group than in the other groups in non-AF. Conversely, there were no significant differences across all groups in AF patients. In conclusion, in patients with acute HF and AF, disproportionately low BNP levels are associated with LA structural remodeling and poor prognosis.

Keywords: acute heart failure; atrial fibrillation; atrioventricular coupling; left atrial volume; natriuretic peptide deficiency; pericardial restraint.