The Effect of Epicardial Fat on the Right and Left Ventricular Function in Subjects with Various Etiological Types of Pulmonary Arterial Hypertension

Abstract

Background: Little is known on the effect of epicardial fat in pulmonary arterial hypertension (PAH). Therefore, the present study sought to perform a comparative analysis on the influence of epicardial fat thickness (EFT) on the right and left ventricular function, between three different etiological varieties of pulmonary arterial hypertension: caused by congenital heart defects (atrial septum defects with left to right shunt), by systemic sclerosis, and by myocardial ischemia. Materials and Methods: This is a prospective observational study on 50 patients with documented PAH (systolic pulmonary artery pressure -PASP of >35 mmHg). The thickness of the epicardial adipose tissue was evaluated by 2D cardiac ultrasound, on the free wall of the right ventricle, during end-diastole, in the long parasternal axis view. The patients were divided into three study groups: Group 1 -PAH determined by congenital heart defects with left to right shunts (atrial septum defects, n = 25); Group 2 -PAH induced by systemic sclerosis (n = 12); Group 3 -PAH induced by myocardial ischemia (n = 13). Results: The average age was 54.48 ± 10.78 years, 30% (n = 15) of subjects were males, with a mean body mass index of 24.65 ± 4.40 kg/m 2 , EFT was 9.15 ± 2.24 mm, and the PASP was 41.33 ± 5.11 mmHg. Patients in Group 3 were more likely to smoke (p = 0.025) and presented a significantly lower LVEF, compared to the other groups (Group 1: 60% ± 6 vs. Group 2: 60% ± 7 vs. Group 3: 48% ± 7, p <0.0001). The largest EFT was found in Group 3 (11.08 ± 2.39 mm), followed by Group 2 (9.14 ± 2.03 mm), and Group 1 (8.16 ± 1.57 mm) (p = 0.0003). The linear regression analysis found no significant correlations between EFT and other echocardiographic parameters: PASP (r = -0.228, p = 0.118), LVEF (r = -0.265, p = 0.06), TAPSW (r = 0.015, p = 0.912), TEI (r = 0.085, p = 0.552), RVEDD (r = -0.195, p = 0.173), RA area (r = -178, p = 0.214), and LA diameter (r = 0.065, p = 0.650). Conclusions: Epicardial fat thickness was found to be significantly higher in patients with PAH induced by myocardial ischemia, followed by those with systemic sclerosis and congenital heart defects, respectively. EFT did not influence the echocardiographic parameters for left and right ventricular function in patients with pulmonary arterial hypertension of different etiologies.

A systematic review exploring the significance of measuring epicardial fat thickness in correlation to B-type natriuretic peptide levels as prognostic and diagnostic markers in patients with or at risk of heart failure

“…Furthermore, evidence from the current review highlights a clear correlation between increased EFT and elevated levels of BNP/NT-proBNP in individuals with an increased risk of heart failure, particularly in the presence of illnesses such as CAD. Similar observations were identified in patients with systemic sclerosis [ 39 ], a condition consistent with overt CVD-related complications such as fibrosis, myocarditis, pulmonary hypertension and blood vessel abnormalities [ 49 – 51 ]. Interestingly, patients with AIS also displayed increased EFT, which was positively correlated with NT-proBNP levels [ 40 ].…”

The Multifaceted Role of Epicardial Fat in Cardiovascular Diseases

“…4 In the third article, Rat et al prove that besides its role as marker of plaque vulnerability, epicardial fat could also serve as a marker of increased risk in other diseases such as pulmonary hypertension associated with various conditions: congenital heart diseases and coronary artery diseases, or secondary to sclerodermia. 5 All three articles have in common the focus on epicardial fat as an inflammation-related marker easily identified by imaging techniques, from classical echocardiography to modern cardiac computed tomography. However, they underline the need for further investigation in this direction, as they only open new hypotheses.…”