PEDS7: Balloon Atrial Septostomy versus Left Atrial Cannulation for Left Heart Decompression in Children with Dilated Cardiomyopathy and Myocarditis on Extracorporeal Membrane Oxygenation

Purpose: To describe the association of left heart decompression with balloon atrial septostomy (BAS) compared to left atrial (LA) cannulation with survival in children with myocarditis or dilated cardiomyopathy (DCM) on veno-arterial extracorporeal membrane oxygenation (ECMO). Methods: Retrospective study of the Extracorporeal Life Support Organization (ELSO) multicenter registry of patients ≤ to 18 years old with myocarditis or DCM on ECMO who underwent LA decompression. Only index ECMO run within a hospitalization was included. Descriptive and univariate statistics assessed association of patient factors with decompression type. Multivariable logistic regression sought independent associations with outcomes. Results: 321 pediatric ECMO runs were identified. 57% myocarditis (n=183) and 43% DCM (n=138). Survival overall was 74%. 67% underwent balloon atrial septostomy (BAS) and 33% underwent left atrial cannulation. Patient demographics including age, weight, gender, race/ethnicity, diagnosis, pre-ECMO pH, mean airway pressure, and arrest status were similar between groups. Median ECMO duration was longer in the BAS group compared to LA cannulation (7.2 versus 5.7 days respectively, p=0.002). 82 (78%) were centrally versus peripherally (22%, n=23) cannulated on ECMO in the LA cannulation group, versus 19 (9%) centrally versus 194 (91%) peripherally cannulated in the BAS group. On multivariable analysis, we found LA cannulation (OR 3.68; 95% CI, 1.86-7.31; p<0.001), neurologic complication (OR 5.25; 95% CI, 2.38-11.58; p<0.001), renal complication (OR 2.74; 95% CI, 1.41-5.29; p=0.003), and cardiac complication (OR 2.64; 95% CI, 1.30-5.38; p=0.007) were associated with greater odds of mortality. There were more episodes of pulmonary hemorrhage in the BAS group (n=17) compared to the LA cannulation group (n=2). Conclusions: Our findings indicate better left heart decompression with an LA cannula compared to BAS given a lower incidence of pulmonary hemorrhage in the LA cannulation group. There was a three times greater likelihood for mortality in children with myocarditis and DCM on ECMO who undergo LA cannulation compared to BAS, however, they appear to be fundamentally different cohorts. Further prospective evaluation with adjustment for severity of illness is warranted.