Percutaneous Atrial Septostomy in Adult Patients on Veno-Arterial Extracorporeal Membrane Oxygenation for Cardiogenic Shock: A Canadian Single-Center Experience

<b>Background/Objectives:</b> Patients with cardiogenic shock on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) frequently develop left ventricular (LV) distension and pulmonary edema due to an increased LV afterload. A balloon atrial septostomy (BAS) is a technique used to alleviate LV pressure and facilitate left atrial decompression. While primarily performed in pediatric populations, this procedure's feasibility in adult patients is less studied. This study aimed to evaluate the procedural outcomes, including the safety and effectiveness, of BASs in adult patients with cardiogenic shock supported by VA-ECMO. <b>Methods:</b> This single-center retrospective study included 11 adult patients with cardiogenic shock on VA-ECMO, who underwent a BAS between 2012 and 2023. Multiple parameters were used to evaluate the global clinical impact of a BAS on patients with cardiogenic shock. <b>Results:</b> Between 2012 and 2023, 11 patients with cardiogenic shock on VA-ECMO underwent a BAS procedure in our institution. The mean time from the BAS to advanced therapy was 6.4 days. Procedural success was achieved in all patients with no complications. Nine patients (82%) had an improvement in PaO₂/FiO₂ 24 h post-BAS procedure. All patients had an improvement in the pulmonary edema on the chest X-ray 24 to 48 h after the procedure, with clear radiography achieved in nine patients (82%) in a mean time of 7 days (range: 1.5-13 days). A total of five patients (45%) had in-hospital mortality due to non-procedural complications and the mortality timing from BAS was between 5 to 23 days. Among those discharged, all six patients were alive at the 1-year follow-up. <b>Conclusions:</b> A BAS is a feasible and safe technique for decompressing the left atrium in adult patients on VA-ECMO. It significantly improved pulmonary edema and oxygenation in most cases. Further studies with larger populations are needed to evaluate its impact on long-term outcomes.