Abstract 155: Elevated Risk of Venous Thromboembolism in Patients Undergoing Targeted Temperature Management After Cardiac Arrest

Introduction: Therapeutic hypothermia (TH) reduces mortality and improves neurological outcomes after cardiac arrest. Cardiac arrest is considered a pro-thrombotic state. Endovascular cooling catheters may increase the risk of thrombosis. Therapeutic hypothermia (TH), however, increases fibrinolysis. These opposing effects may expose patients to both bleeding and venous thromboembolic risk during and after therapeutic hypothermia. The net effect in these patientsremains largely unexplored. Moreover, the exact rate of venous thromboembolism (VTE) is uncertain in these patients. We sought to determine the incidence and potential predictors of VTE in patients undergoing TH after cardiac arrest and compare it to a control group with similar risk of VTE. Methods: Single center retrospective analysis. Participants were age ≥18 years old, admitted to Hartford Hospital with out-of-hospital or in-hospital cardiac arrest, underwent TH between January 1, 2007 and April 30, 2019 with endovascular cooling catheter. A total of 562 patients who underwent TH (Study group) were compared to 304 matchedpatientstreated in the medical ICU with a diagnosis of ARDS (control group). This control group was based on presumed similarities in factors affecting VTE: intensive care setting, immobility, length of stay and likely presence of central venous catheters. Results: Patients who underwent TH had a significantly higher rate of VTE (6.6% vs 4.6%, p=0.006) and deep vein thrombosis (DVT) (2.3% vs 1.3%, p=0.011) when compared to control group. The rate of pulmonary embolism was higher in the TH group, but this was not statistically significant (2.5% and 1.0%, p=0.128). In multivariate analysis age, gender, race and hospital length of stay were not associated with development of VTE in the study group. Conclusion: Patients undergoing TH after cardiac arrest have statistically higher incidence of VTE and DVT compared to patients with ARDS. This risk is independent of age, gender, race or length of stay. Further research into additional independent predictors of VTE and DVT in this population may eventually guide the management and potential future interventions.

Out-of-hospital initiation of hypothermia in ST-segment elevation myocardial infarction: a randomised trial

ObjectiveTo evaluate the effect of prereperfusion hypothermia initiated in the out-of-hospital setting in awake patients with ST-segment elevation myocardial infarction (STEMI) on myocardial salvage measured by cardiac MRI (CMR).MethodsHypothermia was initiated within 6 hours of symptom onset by the emergency medical service with surface cooling pads and cold saline, and continued in the cath lab with endovascular cooling (target temperature: ≤35°C at time of reperfusion). Myocardial salvage index (using CMR) was compared in a randomised, controlled, open-label, endpoint blinded trial to a not-cooled group of patients at day 4±2 after the event.ResultsAfter postrandomisation exclusion of 19 patients a total of 101 patients were included in the intention-to-treat analysis (control group: n=54; hypothermia group: n=47). Target temperature was reached in 38/47 patients (81%) in the intervention group. Study-related interventions resulted in a delay in time from first medical contact to reperfusion of 14 min (control group 89±24 min; hypothermia group 103±21 min; p<0.01). Myocardial salvage index was 0.37 (±0.26) in the control group and 0.43 (±0.27) in the hypothermia group (p=0.27). No differences in cardiac biomarkers or clinical outcomes were found. In a CMR follow-up 6 months after the initial event no significant differences were detected.ConclusionOut-of-hospital induced therapeutic hypothermia as an adjunct to primary percutaneous coronary intervention did not improve myocardial salvage in patients with STEMI.Trial registration numberNCT01777750