Endovascular therapeutic hypothermia adjunctive to percutaneous coronary intervention in acute myocardial infarction: realistic simulation as a game changer.

BACKGROUND: Endovascular therapeutic hypothermia (ETH) reduces the damage by ischemia/reperfusion cell syndrome in cardiac arrest and has been studied as an adjuvant therapy to percutaneous coronary intervention (PCI) in ST-elevation myocardial infarction (STEMI). New available advanced technology allows cooling much faster, but there is paucity of resources for training to avoid delays in door-to-balloon time (DTB) due to ETH and subsequently coronary reperfusion, which would derail the procedure. The aim of the study was to describe the process for the development of a simulation, training & educational protocol for the multidisciplinary team to perform optimized ETH as an adjunctive therapy for STEMI. METHODS AND RESULTS: We developed an optimized simulation protocol using modern mannequins in different realistic scenarios for the treatment of patients undergoing ETH adjunctive to PCI for STEMIs starting from the emergency room, through the CathLab, and to the intensive care unit (ICU) using the Proteus® Endovascular System (Zoll Circulation Inc™, San Jose, CA, USA). The primary endpoint was door-to-balloon (DTB) time. We successfully trained 361 multidisciplinary professionals in realistic simulation using modern mannequins and sham situations in divisions of the hospital where real patients would be treated. The focus of simulation and training was logistical optimization and educational debriefing with strategies to reduce waste of time in patient's transportation from different departments, and avoiding excessive rewarming during transfer. Afterwards, the EHT protocol was successfully validated in a trial randomizing 50 patients for 18 minutes cooling before coronary recanalization at the target temperature of 32 ± 1.0 ∘C or PCI-only. A total of 35 patients underwent ETH (85.7% [30/35] in 90 ± 15 minutes), without delays in the mean door-to-balloon time for primary PCI when compared to 15 control group patients (92.1 minutes versus 87 minutes, respectively; p = 0.509). CONCLUSIONS: Realistic simulation, intensive training and educational debriefing for the multidisciplinary team propitiated feasible endovascular therapeutic hypothermia as an adjuvant therapy to primary PCI in STEMI. CLINICALTRIALS: gov: NCT02664194.

Cooling as an Adjunctive Therapy to Percutaneous Intervention in Acute Myocardial Infarction: COOL-MI InCor Trial.

Endovascular Therapeutic hypothermia (ETH) reduces the damage caused by postischemia reperfusion injury syndrome in cardiopulmonary arrest and has already established its role in patients with sudden death; however, its role in ST-segment elevation myocardial infarction (STEMI) remains controversial. The objectives of this study were to investigate the safety, feasibility, and 30-day efficacy of rapid induction of therapeutic hypothermia as adjunctive therapy to percutaneous coronary intervention (PCI) in patients with anterior and inferior STEMIs. This was a prospective, controlled, randomized, two-arm, prospective, interventional study of patients admitted to the emergency department within 6 hours of angina onset, with anterior or inferior STEMI eligible for PCI. Subjects were randomized to the hypothermia group (primary PCI+ETH) or to the control group (primary PCI) at a 4:1 ratio. The ETH was induced by 1 L cold saline (1-4°C) associated with the Proteus™ System, by cooling for at least 18 minutes before coronary reperfusion with a target temperature of 32°C ± 1°C. Maintenance of ETH was conducted for 1-3 hours, and active reheating was done at a rate of 1°C/h for 4 hours. Primary safety outcomes were the feasibility of ETH in the absence of (1) door-to-balloon (DTB) delay; (2) major adverse cardiac events (MACE) within 30 days after randomization. The primary outcomes of effectiveness were infarct size (IS) and left ventricular ejection fraction (LVEF) at 30 days. An as-treated statistical analysis was performed. Fifty patients were included: 35 (70%) randomized to the hypothermia group and 15 (30%) to the control group. The mean age was 58 ± 12 years; 78% were men; and associated diseases were 60% hypertension, 42% diabetes, and 72% dyslipidemia. The compromised myocardial wall was anterior in 38% and inferior in 62%, and the culprit vessels were left anterior descending artery (LAD) (40%), right coronary artery (38%), and left circumflex (18%). All 35 patients who attempted ETH (100%) had successful cooling, with a mean endovascular coronary reperfusion temperature of 33.1°C ± 0.9°C. The mean ischemic time was 375 ± 89.4 minutes in the hypothermia group and 359.5 ± 99.4 minutes in the control group. The mean DTB was 92.1 ± 20.5 minutes in the hypothermia group and 87 ± 24.4 minutes in the control group. The absolute difference of 5.1 minutes was not statistically significant (p = 0.509). The MACE rates were similar between both groups (21.7% vs. 20% respectively, p = 0.237). In the comparison between the hypothermia and control groups, no statistically significant differences were observed at 30 days between mean IS (13.9% ± 8% vs. 13.8% ± 10.8%, respectively, p = 0.801) and mean final LVEF (43.3% ± 11.2% vs. 48.3 ± 10.9%, respectively; p = 0.194). Hypothermia as an adjunctive therapy to primary PCI in STEMI is feasible and can be implemented without delay in coronary reperfusion. Hypothermia was safe regarding the incidence of MACE at 30 days. However, there was a higher incidence of arrhythmia and in-hospital infection in the hypothermia group, with no increase in mortality. Regarding efficacy, there was no difference in IS or LVEF at 30 days that would suggest additional myocardial protection with ETH. ClinicalTrials.gov: NCT02664194.