Prognostic value of epicardial and pericardial adipose tissue in patients with chronic heart failure

Abstract Background The prognostic value of increased body mass index (BMI) in patients wth heart failure (HF) is not clear and an obesity-survival paradox has been described. Recent studies have advocated against the existence of such paradox by showing that alternative anthropometric measurements reflecting adiposity were associated with poor outcomes in HF, irrespective of BMI. However, these measures remain limited in assessing the actual amount and distribution of adipose tissue. Epicardial adipose tissue (EAT) and pericardial adipose tissue (PAT) are suggested to be involved in the development of HF. While an increased EAT and PAT thickness has been described in HF, their prognostic value has not been extensively investigated. Aims To investigate the prognostic value of EAT and PAT in patients with chronic HF. Methods Between 2012 and 2018, 625 patients with a recent (<3 months) diagnosis of HF with reduced, mildly reduced or preserved ejection fraction (HFrEF, HFmrEF and HFpEF) were referred to a specialized nurse-led HF clinic for protocolized up-titration of guideline-directed medical therapy in our centre. All patients underwent baseline echocardiography and were followed up for the combined outcome parameter of all-cause mortality and HF hospitalisation. EAT and PAT thickness were measured on baseline echocardiography and expressed in mm. Results In total, 618 patients were included. Mean age was 67±14 years and 381 were men (62%). 374 patients (61%) had HFrEF, 108 (17%) HFmrEF and 136 (22%) HFpEF. Mean BMI was 27.3±5.7 kg/m2, mean EAT thickness 4.8±2.1 mm and mean PAT thickness 5.6±2.8 mm. Across the HF types HFrEF, HFmrEF and HFpEF, there was a significant difference in BMI (26.7±5.3 vs. 27.0±5.3 vs. 29.0±6.8 kg/m2, p<0.001, respectively), EAT thickness (4.5±2.1 vs. 4.8±1.7 vs. 5.4±2.1 mm, p<0.001, respectively) and PAT thickness (5.4±2.4 vs. 5.4±2.9 vs. 6.4±3.6 mm, p=0.002, respectively). During a mean follow-up of 3.2±1.9 years, 217 patients (35%) experienced the combined outcome parameter. Both EAT [HR 1.16 (95% CI 1.03-1.30), p=0.01] and PAT [HR 1.25 (95% CI 1.10-1.41), p<0.001] were associated with outcome, while BMI was not [HR 0.96 (95% CI 0.84-1.10), p=0.6]. In a multivariable analysis, PAT remained associated with outcome after adjustment for age, gender, BMI, EAT, NT-proBNP, LVEF and eGFR [HR 1.20 (95% CI 1.05-1.38), p=0.008). In Kaplan-Meier analyses, only higher PAT thickness was associated with poor outcome (Log rank p<0.001, Figure). PAT thickness was associated with poor outcome both in HFrEF [HR 1.27 (95% CI 1.04-1.55), p=0.02] and in HFpEF [HR 1.25 (95% CI 1.05-1.48), p=0.02]. Conclusion Increased PAT thickness, more than EAT thickness, is strongly associated with poor outcome in patients with chronic heart failure, both HFrEF and HFpEF, and irrespective of BMI.Kaplan-meier analyses