Left atrial volume and left ventricular mass indices in heart failure with preserved and reduced ejection fraction

Aims: Two key echocardiographic parameters that are currently used to diagnose heart failure (HF) with preserved ejection fraction (HFpEF) are left atrial volume index (LAVi) and left ventricular mass index (LVMi). We investigated whether patients' characteristics, biomarkers, and co-morbidities are associated with these parameters and whether the relationships differ between patients with HFpEF or HF with reduced ejection fraction (HFrEF). Methods: We consecutively enrolled 831 outpatients with typical signs and symptoms of HF and elevated N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels and categorized patients based upon left ventricular ejection fraction (LVEF): LVEF < 40% (HFrEF), LVEF between 40% and 50% (HF with mid-range ejection fraction), and LVEF ≥ 50% (HFpEF). The study includes consecutively enrolled HF patients from an HF outpatient clinic at a tertiary medical centre in the Netherlands. All patients underwent baseline characterization, laboratory measurements, and echocardiography. Results: Four hundred sixty-nine patients had HFrEF, 189 HF with mid-range ejection fraction, and 173 HFpEF. The patients with HFrEF were rather male [HFrEF: 323 (69%); HFpEF: 80 (46%); P < 0.001], and the age was comparable (HFrEF 67 ± 13; HFpEF 70 ± 14; P = 0.069). In HFpEF, more patients had hypertension [190 (40.5%); 114 (65.9%); P < 0.001], higher body mass indices (27 ± 8; 30 ± 7; P < 0.001), and atrial fibrillation [194 (41.4); 86 (49.7); P = 0.029]. The correlation analyses showed that in HFrEF patients, LAVi was significantly associated with age (β 0.293; P < 0.001), male gender (β 0.104; P = 0.042), body mass index (β −0160; P = 0.002), diastolic blood pressure (β −0.136; P < 0.001), New York Heart Association (β 0.174; P = 0.001), atrial fibrillation (β 0.381; P < 0.001), galectin 3 (β 0.230; P < 0.001), NT-proBNP (β 0.183; P < 0.001), estimated glomerular filtration rate (β −0.205; P < 0.001), LVEF (β −0.173; P = 0.001), and LVMi (β 0.337; P < 0.001). In HFpEF patients, only age (β 0.326; P < 0.001), atrial fibrillation (β 0.386; P < 0.001), NT-proBNP (β 0.176; P = 0.036), and LVMi (β 0.213; P = 0.013) were associated with LAVi. Conclusions: Although LVMi and LAVi are hallmark parameters to diagnose HFpEF, they only correlate with a few characteristics of HF and mainly with atrial fibrillation. In contrast, in HFrEF patients, LAVi relates strongly to several other HF parameters. These findings underscore the complexity in visualizing the pathophysiology of HFpEF and question the relation between cardiac structural remodeling and the impact of co-morbidities.