Right Ventricular Reverse Remodeling after Pulmonary Endarterectomy in Patients with Chronic Thrombo Embolic Pulmonary Hypertension

Abstract

Purpose Chronic thrombo-embolic pulmonary hypertension (CTEPH) leads to right ventricular (RV) adverse remodeling if left untreated. We recently compared RV features between CTEPH patients and healthy controls. We found that capillary rarefaction, myocardial fibrosis, cardiomyocytes hypertrophy and increased macrophages infiltration were associated with impaired ventricular-arterial coupling, RV dysfunction and increased glucose uptake. Pulmonary endarterectomy (PE) is the treatment of choice for CTEPH, resulting in a marked decrease in RV afterload. In this study, we sought to investigate the correlations between preoperative RV pathological features and postoperative RV function and metabolism. Methods We followed 9 CTEPH patients undergoing PE during which we performed RV biopsies. RV phenotype was assessed using cardiac magnetic resonance, resting echocardiography and 18-Fluoro-Deoxi-Glucose Positron Emission Tomography before PE, and at 1- and 6-months post operatively. Results RV systolic pressures decreased in all patients at 1 month follow-up. Similarly, indices of RV function, remodeling, glucose uptake and coupling as assessed by the Stroke Volume/End Systolic Volume ratio significantly improved at 6 months follow-up. Improvement of RV ejection fraction and RV end systolic volume index were correlated to pre-operative cardiomyocytes hypertrophy (Figure 1). There was a trend for an association between RV fibrosis and moderate improvement in RV systolic function after PE. Preoperative macrophage infiltration and capillary density did not impact on postoperative RV functional recovery. Conclusion After PE, RV phenotype was associated with marked improvement in RV systolic function 6 months, which correlated with pre-operative cardiomyocytes hypertrophy. RV fibrosis was not associated with impaired outcomes and did not limit RV functional recovery in this study. Chronic thrombo-embolic pulmonary hypertension (CTEPH) leads to right ventricular (RV) adverse remodeling if left untreated. We recently compared RV features between CTEPH patients and healthy controls. We found that capillary rarefaction, myocardial fibrosis, cardiomyocytes hypertrophy and increased macrophages infiltration were associated with impaired ventricular-arterial coupling, RV dysfunction and increased glucose uptake. Pulmonary endarterectomy (PE) is the treatment of choice for CTEPH, resulting in a marked decrease in RV afterload. In this study, we sought to investigate the correlations between preoperative RV pathological features and postoperative RV function and metabolism. We followed 9 CTEPH patients undergoing PE during which we performed RV biopsies. RV phenotype was assessed using cardiac magnetic resonance, resting echocardiography and 18-Fluoro-Deoxi-Glucose Positron Emission Tomography before PE, and at 1- and 6-months post operatively. RV systolic pressures decreased in all patients at 1 month follow-up. Similarly, indices of RV function, remodeling, glucose uptake and coupling as assessed by the Stroke Volume/End Systolic Volume ratio significantly improved at 6 months follow-up. Improvement of RV ejection fraction and RV end systolic volume index were correlated to pre-operative cardiomyocytes hypertrophy (Figure 1). There was a trend for an association between RV fibrosis and moderate improvement in RV systolic function after PE. Preoperative macrophage infiltration and capillary density did not impact on postoperative RV functional recovery. After PE, RV phenotype was associated with marked improvement in RV systolic function 6 months, which correlated with pre-operative cardiomyocytes hypertrophy. RV fibrosis was not associated with impaired outcomes and did not limit RV functional recovery in this study.