Abstract 4147497: Post Cardiac Arrest Temperature Management: Therapeutic Normothermia and Hypothermia Effect on Cardiac Function

Background: There is strong data about the neuroprotective effects of targeted temperature management (TTM) in patients post cardiac arrest, however, there is limited literature on the cardiac effects. We evaluate the impact of targeted normothermia (TN) vs targeted hypothermia (TH) on left ventricular ejection fraction (LVEF). We hypothesized that targeted hypothermia would be more cardioprotective than targeted normothermia, thus manifesting in improved LVEF and/or reduced incidence of new heart failure at various points in time. Method: We queried the TriNetX Global collaborative network for adult (≥18 years) patients with LVEF >50% who suffered a Cardiac arrest (CA) and Coma within one day of CA, and we created two groups: therapeutic hypothermia and therapeutic normothermia. TTM was identified with International Classification of Diseases 10th edition (ICD-10) Procedure codes 6A4Z0ZZ, 6A4Z1ZZ, and SNOMED code 308693008 and the TN group excluded patients with documented temperature ≥ 99.6 °F or ≤ 97.6 °F within 1 day of CA. Similarly, the TH group was identified using the same ICD codes and excluded patients with documented temperatures ≥96.7°F or ≤ 91.3°F within 1 day of CA being excluded. Propensity Score Matching (PSM) done for age, race, sex, and multiple cardiovascular comorbidities. Outcomes were measured at 3-, 12-, and 36 months post-CA included the risk of LVEF ≤ 50%, new onset heart failure, and new prescription of loop diuretic. Results: After PSM 510 patients were analyzed, with 255 well-matched subjects in each group. At 3 months there were no significant odds of TH causing a decrease in cardiac ejection fraction to 50% or less (Odds Ratio [OR] 0.90, 95% CI: 0.37 – 2.18) compared to TN. No significant difference was seen at 12 months (OR 0.897, 95% CI: 0.37 – 2.18) or 36 months (OR 0.71, 95% CI: 0.32 – 1.60). Other outcomes at 3 months without significant difference include new HF (OR 0.97, 95% CI: 0.39 – 2.43), and new loop diuretic (OR 0.77, 95% CI: 0.33 – 1.80). These odds were similarly not significant at 12 and 36 months. Conclusions: In post-CA patients who received TTM, no cardioprotective effects were appreciated between hypothermia compared to normothermia at 3-, 12-, and 36 month follow up. There was no difference in new diagnosis of HF post-CA or new loop diuretic prescription. With the understanding that TN has fewer side effects than TH then the results reinforce the use of TN post cardiac arrest.