Abstract Body (Do not enter title and authors here): Background:
Following an out of hospital cardiac arrest (OHCA), rhythm strips stored on an automated external defibrillator (AED) help guide important medical decisions, including possible implantable cardioverter defibrillator (ICD) implantation. However, this information is often difficult to obtain.

Objective:
To evaluate how frequently AED rhythm strips are reviewed following an OHCA prior to placing an ICD.

Methods:
Using the Cardiac Arrest Registry to Enhance Survival (CARES), we identified patients from 1/2015-12/2023 who were transferred to our institution following an OHCA. Patients were excluded if resuscitation was not attempted, death occurred during the hospitalization or patient identifying information was not available.

Results:
Of 907 OHCAs identified, 119 patients (Table 1) met the inclusion criteria. The AED rhythm strip was in the electronic medical record on hospital arrival in 22% of cases and only after provider initiation in 6% of cases. None of the rhythm strips from a bystander-only delivered AED shock (n=17) were available on arrival, with only 24% retrieved during the hospitalization, taking 4.5±2.1 days from the date of arrest. Patients with an AED rhythm strip available (n=34) were more likely than those without a rhythm strip (n=85) to have a cardiac MRI (38% v. 13%, p=0.02) and genetic testing (15% v. 1%, p=0.02) done and have an ICD placed (53% v. 27%, p=0.04) or be discharged on a new anti-arrhythmic drug (15% v. 4%, p=0.04). Figure 1 Of the 42 patients who had an ICD placed during the index hospitalization, 54% were implanted without knowing the type of shockable rhythm or confirmation that an appropriate AED shock had been delivered.

Conclusion:
Rhythm strips help guide clinical decisions when assessing the need for ICD implantation. There is a systems gap in the process of transferring rhythm strips from AEDs to hospital providers following an OHCA.