The prognostic impact of therapeutic hypothermia after a sudden cardiac arrest in the course of myocardial infarction

Cardiol J. 2022 Aug 17. doi: 10.5603/CJ.a2022.0077. Online ahead of print.

Abstract

Background: Mild therapeutic hypothermia (MTH) is one of the treatment methods recommended in post-sudden cardiac arrest (SCA) patients who remain unconscious after cardiopulmonary resuscitation. The present study aimed at assessing the prognostic impact of intravascular MTH on invasively treated patients with an acute myocardial infarction complicated by SCA.

Methods: The presented data were collected via a single-center retrospective analysis of the hospitalization and follow-up of 54 patients with post-myocardial infarction complicated by SCA. The patients were treated in the years 2014-2020 and the average follow-up period was 1141 ± 163 days. The population was divided into two groups: 28 patients treated with MTH (a therapeutic hypothermia [TH] group) and 26 patients treated without MTH (a non-TH group).

Results: The results indicate a trend toward improved in-hospital prognosis in the TH group, but the differences did not reach statistical significance: TH 25.0% vs. non-TH 34.5%, p = 0.554. An additional analysis of younger patients (under 60 years of age) revealed no significant differences between the TH and non-TH subgroups concerning in-hospital survival (in-hospital mortality rate: TH 6.7% vs. non-TH 30.0%, p = 0.267). Still, TH patients aged < 60 achieved a significantly better rate of follow-up survival (p = 0.041). The older (≥ 60) patient group showed no in-hospital mortality rate differences (TH 46.2% vs. non-TH 37.5%, p = 0.638). However, in-hospital bleeding frequency was significantly higher in patients aged ≥ 60 from the hypothermia group (TH 50.0% vs. non-TH 6.7%, p = 0.011).

Conclusions: Intravascular MTH may improve the follow-up prognosis in patients aged < 60 with SCA in the early phase of myocardial infarction.

Keywords: cardiac arrest; myocardial infarction; target temperature management; therapeutic hypothermia.