Abstract 217: Chest Compression on Aortic Valve Decreases Chance of Return of Spontaneous Circulation for Patients Experiencing Out-of-Hospital Cardiac Arrest

Abstract

Background: Current CPR guidelines recommend applying chest compression at "the center of the chest" for patients undergoing out-of-hospital cardiac arrest (OHCA). However, studies revealed that following this recommendation, around half of OHCA patients would receive compressions on the aortic valve (AV), potentially obstructing blood flow and worsening prognosis. Hypothesis and Aim: We aimed to use transesophageal echocardiography (TEE) during cardiopulmonary resuscitation (CPR) to test the hypothesis of the impact of AV compression vs AV non-compression on adult OHCA patients' outcomes. Methods: This prospective cohort study included OHCA patients receiving TEE exams during CPR. Exclusion criteria were the return of spontaneous circulation (ROSC) before TEE, unidentifiable compression site, or unqualified TEE image. Patients were divided into AV-compressed or non-compressed groups based on initial TEE findings. Patient characteristics, TEE recordings, resuscitation data, and critical time points were analyzed. Primary outcome was sustained ROSC. Secondary outcomes included any ROSC, survival to admission, survival to discharge, and favorable neurological outcomes upon discharge defined by MRS ≤ 2. The sample size was pre-estimated as 37 patients per group. Results: A total of 76 patients from October 2020 to January 2023 were enrolled for analysis, with 39 in the AV non-compressed group and 37 in the AV-compressed group. Baseline characteristics were similar between groups. Compared to the compressed group, the non-compressed group had a better chance of sustained ROSC [adjusted odds ratio (aOR) 4.72, p=0.010], any ROSC (aOR 3.30, p=0.033), and survival to admission (aOR 6.74, p=0.010). The main results were tabulated as below. Conclusions: CPR with compressed AV decreased the chances of ROSC among OHCA patients.