Introduction: Pulmonary endarterectomy (PEA) is known to be a curative intervention for chronic thromboembolic pulmonary hypertension (CTEPH). Its complications include endobronchial bleeding, persistent pulmonary arterial hypertension, right ventricular failure, and reperfusion lung injury. Extracorporeal membranous oxygenation (ECMO) is a perioperative salvage method for PEA. Although risk factors and outcomes have been reported in several studies, overall trends remain unknown. We performed a systematic review and study-level meta-analysis to understand the outcomes of ECMO utilization in the perioperative period of PEA. Methods: We performed a literature search with PubMed and EMBASE on 11/18/2022. We included studies including patients who underwent perioperative ECMO in PEA. We collected data including baseline demographics, hemodynamic measurements, and outcomes such as mortality and weaning of ECMO and performed a study-level meta-analysis. Results: Eleven studies with 2632 patients were included in our review. ECMO insertion rate was 8.7% (225/2,625, 95% CI 5.9-12.5) in total, VV-ECMO was performed as the initial intervention in 1.1% (41/2,625, 95% CI 0.4-1.7) (Figure 3), and VA-ECMO was performed as an initial intervention in 7.1% (184/2,625, 95% CI 4.7-9.9). Preoperative hemodynamic measurements showed higher pulmonary vascular resistance, mean pulmonary arterial pressure, and lower cardiac output in the ECMO group. Mortality rates were 2.8% (32/1238, 95% CI: 1.7-4.5) in the non-ECMO group and 43.5% (115/225, 95% CI: 30.8-56.2) in the ECMO group. The proportion of patients with successful weaning of ECMO was 72.6% (111/188, 95% CI: 53.4-91.7). Regarding complications of ECMO, the incidence of bleeding and multi-organ failure were 12.2% (16/79, 95% CI: 13.0-34.8) and 16.5% (15/99, 95% CI: 9.1-28.1), respectively. Conclusion: Our systematic review showed a higher baseline cardiopulmonary risk in patients with perioperative ECMO in PEA, and its insertion rate was 8.7%. Further studies that compare the use of ECMO in high-risk patients who undergo PEA are anticipated.
Keywords: chronic thromboembolic pulmonary hypertension; extracorporeal membranous oxygenation; pulmonary endarterectomy; pulmonary hypertension.