Impact of Left Atrial Decompression on Patient Outcomes During Pediatric Venoarterial Extracorporeal Membrane Oxygenation: A Case-Control Study

Left heart distension during venoarterial extracorporeal membrane oxygenation (VA ECMO) often necessitates decompression to facilitate myocardial recovery and prevent life-threatening complications. The objectives of this study were to compare clinical outcomes between patients who did and did not undergo left atrial (LA) decompression, quantify decompression efficacy, and identify risk factors for development of left heart distension. This was a single-center retrospective case-control study. Pediatric VA ECMO patients who underwent LA decompression from June 2004 to March 2016 were identified, and a control cohort of VA ECMO patients who did not undergo LA decompression were matched based on diagnosis, extracorporeal cardiopulmonary resuscitation, and age. Among 194 VA ECMO cases, 21 (11%) underwent LA decompression. Compared to the control cohort, patients with decompression had longer hospital length of stay (60 +/- 55 vs. 27 +/- 23 days, p = 0.012), but similar in-hospital mortality (29% vs. 38%, p = 0.513). Decompression successfully decreased mean LA pressure (24 +/- 11 to 14 +/- 4 mmHg, p = 0.022) and LA:RA pressure gradient (10 +/- 7 to 0 +/- 1 mmHg, p = 0.011). No significant differences in early quantitative measures of cardiac function were observed between cases and controls to identify risk factors for left heart distension. Despite higher qualitative risk for impaired cardiac recovery, patients who underwent LA decompression had comparable outcomes to those who did not. Given that traditional quantitative measures of cardiac function are insufficient to predict development of eventual left heart distension, a combination of clinical history, radiographic findings, hemodynamic monitoring, and laboratory markers should be used during the evaluation and management of these patients.