Abstract 4354734: Favorable Outcomes with Preoperative Extracorporeal Membrane Oxygenation Support in Emergent Pulmonary Embolectomy for Acute Pulmonary Embolism

Background: Extracorporeal membrane oxygenation (ECMO) is a last-resort therapy for patients with hemodynamic instability due to acute pulmonary embolism (PE). Some of these patients require emergent pulmonary embolectomy. However, the impact of preoperative ECMO support on surgical outcomes remains unclear. Research Question: Does preoperative ECMO support have a negative impact on the clinical outcomes of pulmonary embolectomy? Methods: Between December 2007 and February 2025, 37 patients underwent emergent pulmonary embolectomy for acute PE. ECMO support was initiated in patients who experienced cardiac arrest (CPA), persistent hemodynamic shock, or unstable circulatory status. Patients were divided into two groups: those who did not receive ECMO (Group A, n=17) and those who did (Group B, n=20). The primary outcome was a composite of in-hospital mortality and CPA requiring cardiopulmonary resuscitation (CPR) following induction of anesthesia. Preoperative characteristics, early surgical outcomes, and late survival were compared between the two groups. Late survival was assessed using the Kaplan–Meier method. Results: No significant differences were observed between groups regarding age (Group A: 58.5 ± 16.0 years; Group B: 58.7 ± 15.0 years; p=0.98), male (Group A: 9; Group B: 15; p=0.16), or body weight (Group A: 62.3 ± 14.6 kg; Group B: 71.9 ± 15.7 kg; p=0.063). All patients underwent surgery via median sternotomy. Operation time was not significantly different between two groups (Group A: 190.1 ± 71.3 minutes; Group B: 228.4 ± 65.2 minutes; p=0.10). In Group A, two patients experienced CPA requiring CPR following induction of anesthesia. One of these patients suffered hypoxic brain injury and subsequently died during hospitalization. Two other patients died during hospitalization. In contrast, none in Group B experienced the primary outcome (Group A: 4 patients; Group B: 0 patients; p=0.036). The mean follow up period after discharge was 46.5 ± 43.2 months. The 5-year freedom from all-cause mortality was significantly lower in Group A (59.7%) compared to Group B (94.1%) (log rank=0.013). Conclusion: Preoperative ECMO support did not worsen clinical outcomes in patients undergoing emergent pulmonary embolectomy for acute PE. On the contrary, it may prevent hemodynamic collapse during anesthesia induction. Aggressive consideration of ECMO support prior to emergent surgery might be warranted in hemodynamically unstable patients.