Epicardial adipose tissue and pericardial constraint in heart failure with preserved ejection fraction.

AIMS: Obesity and epicardial adiposity play a role in the pathophysiology of heart failure with preserved ejection fraction (HFpEF), and both are associated with increased filling pressures and reduced exercise capacity. The haemodynamic basis for these observations remains inaccurately defined. We hypothesize that an abundance of epicardial adipose tissue (EAT) within the pericardial sac is associated with haemodynamic signs of pericardial constraint. METHODS AND RESULTS: HFpEF patients who underwent invasive heart catheterization with simultaneous echocardiography were included. Right atrial pressure (RAP), right ventricular end-diastolic pressure, and pulmonary capillary wedge pressure (PCWP) were invasively measured. The presence of a square root sign on the right ventricular pressure waveform and the RAP/PCWP ratio (surrogate parameters for pericardial constraint) were investigated. EAT thickness alongside the right ventricle was measured on echocardiography. Sixty-four patients were studied, with a mean age of 73 ± 10 years, 64% women, and a mean body mass index (BMI) of 28.6 ± 5.4 kg/m2. In total, 47 patients (73%) had a square root sign. The presence of a square root sign was associated with higher BMI (29.3 vs. 26.7 kg/m2, P = 0.02), higher EAT (4.0 vs. 3.4 mm, P = 0.03), and higher RAP (9 vs. 6 mmHg, P = 0.04). Women had more EAT than men (4.1 vs. 3.5 mm, P = 0.04), despite a comparable BMI. Women with a square root sign had significantly higher EAT (4.3 vs. 3.3 mm, P = 0.02), a higher mean RAP (9 vs. 5 mmHg, P = 0.02), and a higher RAP/PCWP ratio (0.52 vs. 0.26, P = 0.002). In men, such associations were not seen, although there was no significant interaction between men and women (P > 0.05 for all analyses). CONCLUSIONS: Obesity and epicardial adiposity are associated with haemodynamic signs of pericardial constraint in patients with HFpEF. The pathophysiological and therapeutic implications of this finding need further study.

Associations of relative fat mass and BMI with all-cause mortality: Confounding effect of muscle mass.

OBJECTIVE: The study objective was to examine associations of relative fat mass (RFM) and BMI with all-cause mortality in the Dutch general population and to investigate whether additional adjustment for muscle mass strengthened these associations. METHODS: A total of 8433 community-dwelling adults from the PREVEND general population cohort (1997-1998) were included. Linear regression models were used to examine associations of RFM and BMI with 24-h urinary creatinine excretion, a marker of total muscle mass. Cox regression models were used to examine associations of RFM and BMI with all-cause mortality. RESULTS: The mean age of the cohort was 49.8 years (range: 28.8-75.7 years), and 49.9% (n = 4209) were women. In age- and sex-adjusted models, both RFM and BMI were associated with total muscle mass (24-h urinary creatinine excretion), and these associations were stronger with BMI (standardized beta [Sß]RFM : 0.29; 95% CI: 0.27-0.31 vs. SßBMI : 0.38; 95% CI: 0.36-0.40; pdifference < 0.001). During a median follow-up period of 18.4 years, 1640 deaths (19.4%) occurred. In age- and sex-adjusted models, RFM was significantly associated with all-cause mortality (hazard ratio per 1-SD [HRRFM ]: 1.16; 95% CI: 1.09-1.24), whereas BMI was not (HRBMI : 1.04; 95% CI: 0.99-1.10). After additional adjustment for muscle mass, associations of both RFM and BMI with all-cause mortality increased in magnitude (HRRFM : 1.24; 95% CI: 1.16-1.32 and HRBMI : 1.12; 95% CI: 1.06-1.19). Results were broadly similar in multivariable adjusted models. CONCLUSIONS: In the general population, a higher RFM was significantly associated with mortality risk, whereas a higher BMI was not. Adjusting for total muscle mass increased the strength of associations of both RFM and BMI with all-cause mortality.