Abstract 159: Time-course Of Left Ventricular Systolic Dysfunction Recovery After Cardiac Arrest

Abstract

Introduction: Myocardial dysfunction is a well-documented feature of post-cardiac arrest syndrome. The natural history of left ventricular systolic dysfunction (LVSD) remains largely unknown. We sought to characterize the change in left ventricular systolic function after return of spontaneous circulation (ROSC). Methods: This is a retrospective review of cardiac arrest patients at a single tertiary center between 2015 and 2020. We included patients with a transthoracic echocardiogram (TTE) documenting left ventricular ejection fraction (EF) within 1 day of ROSC and at least one follow-up TTE within 6 months after cardiac arrest. LVSD was defined as EF <40% on TTE. Patients with known LVSD preceding cardiac arrest were excluded. Using paired t-test, we compared initial (within 1 day of ROSC) and follow up TTEs, stratified by shockable rhythm status. Recovery of LVSD was defined as improvement in EF to >50%. Results: Of 477 cardiac arrest patients, 89 (18.7%) patients met the inclusion criterion. 28 (31.5%) had a baseline TTE on file; 5 patients had LVSD prior to arrest and were excluded, leaving a cohort of 84 patients. Thirty-one (36.9%) patients had LVSD on TTE after ROSC, of which 16 (51.6%) had recovery of EF on follow up TTE. The figure shows the timeline of EF recovery for the whole cohort. In-hospital follow up TTE (n=84) was done at a median (IQR) of 7 (4,16) days and post-discharge follow up (n=26) at 63 (29, 115) days. In patients with shockable rhythm arrest, EF improved from ROSC to inpatient follow up TTE [mean (SD) 36% (2.6) to 50% (2.5), P <0.001]. Patients with non-shockable rhythm arrest had a higher baseline EF with a non-significant change at follow up [50% (2.6) to 56% (2.5), p=0.072]. Conclusion: Among survivors of cardiac arrest, significant recovery of LVSD was common. Further work is necessary to elucidate predictors of myocardial recovery and to determine optimal timing for repeat echocardiography.