Abstract 16662: Central Lymphatic Dysfunction is a Contributing Cause of Tissue Congestion in Heart Failure

Abstract

Introduction: Symptomatic Heart failure (HF) is a leading cause of morbidity and mortality in the world. HF with right sided symptoms may result in fluid overload including edema and ascites. The pathophysiology of fluid overload is poorly understood with no clear association between symptoms and hemodynamic parameters. Hypothesis: In animals with RHF and elevated CVP, the presence of ascites correlates with changes in lymphatic function and is independent of myocardial function and hemodynamic parameters. Methods: RHF was induced in fifteen swine animals by creating severe tricuspid regurgitation. Hemodynamics and anatomic changes were characterized using fluoroscopy, echocardiogram, and MRI. Measurements of the thoracic duct (TD) were made in the abdomen and thorax and the cross-sectional area was calculated. TD regurgitant flow was identified with ethiodized oil injection into the TD and was noted to be present or absent. Data is reported as median (IQR). Results: All 15 animals developed RHF with a dilated right atrium (RA) and right ventricle (RV). Nine animals developed ascites. Comparing animals with and without ascites, there were no differences in IVC pressure(mmHg) 11.5 (7.7-13.4) vs. 11.9 (10.2-17.4) (p= 0.364), SVC pressure 12.8 (11.3-16.8) vs. 12 (8.3-14.9) (p=0.343). Other hemodynamics parameters including pulmonary artery (PA), RV, and RA pressure were also not significantly different. In addition, left ventricular (LV) ejection fraction was normal in both groups (68.7% (57.9-74.8) vs. 55% (53.1-69.4) (p=0.135)). However, animals in the ascites group had larger relative liver volume (mL/Kg) 59.1 (65.1-51.9) vs. 34.85 (42.3-24.1) (p = 0.003), larger dimension of the minimal TD size (mm) 3.2 (5.8-2.7) vs. 2.2 (2.6-2.0) (p=0.04), and more animals had TD regurgitant flow 89% vs. 16% (p=0.01). Conclusion: In animal model with RV failure, there is no association between hemodynamic parameters and occurrence of ascites, consistent with observations in humans. In contrast, parameters of lymphatic congestion differ significantly between the two groups supporting the notion that lymphatic dysfunction is a contributing cause of tissue congestion in patients with HF and elevated CVP.