Atrial septostomy and left ventricular venting in patients requiring VA-ECMO

Peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides comprehensive pulmonary and circulatory support in refractory cardiogenic shock (CS). Retrograde flow from VA-ECMO is believed to increase left ventricular (LV) afterload. We investigate whether balloon atrial septostomy (BAS) provides effective LV venting in addition to LV unloading in this setting.

We conducted a retrospective analysis of consecutive adult patients in CS who underwent VA-ECMO initiation with concomitant BAS for LV venting between November 2019 and April 2024. Failure of LV venting was defined as a composite outcome including escalation to intra-aortic balloon pump (IABP) or Impella, CVA attributable to VA-ECMO, echocardiographic evidence of LV thrombus, aortic root thrombus, LV distension, spontaneous echo contrast ("smoke") in the LV/aortic root or worsening pulmonary edema on chest x-ray.

Twenty-eight patients underwent VA-ECMO with atrial septostomy. Baseline characteristics are described in the central illustration. LV venting failure occurred in 54% of patients, mostly driven by evidence of pulmonary edema occurring in 39.3% of patients. 30-day mortality in our cohort was 43%.

In select patients, BAS may provide effective LV unloading but warrants a high degree of surveillance to ensure adequate LV venting.

Central Illustration