Impact of therapeutic hypothermia on cardiogenic shock outcomes: a systematic review and meta-analysis

Pre-clinical studies have suggested the benefits of therapeutic hypothermia in cardiogenic shock (CS). However, current evidence on its efficacy and safety in CS remains limited. We performed a systematic review and meta-analysis to assess efficacy/safety of hypothermia in CS. PUBMED/EMBASE/Cochrane/Scopus/Web of Science were searched from inception to December 31, 2024, for studies evaluating outcomes of hypothermia in CS. Efficacy outcome was all-cause mortality. Safety outcomes included pneumonia, sepsis, and bleeding. Seven studies including 695 patients were analyzed. Acute myocardial infarction (AMI)-related CS was the primary etiology in 363 patients (52.2%). Hypothermia was not associated with a significant reduction in all-cause mortality at 30 days (OR 0.83 [0.54-1.26] or at the longest available follow-up (IRR 0.85 [0.72-1.01]). No significant differences were observed for pneumonia (OR 1.44 [0.42-4.87]), sepsis (OR 0.61 [0.01-46.80]), or bleeding (OR 1.36 [0.65-2.89]). Meta-regression suggested that hypothermia may be less beneficial and riskier in patients with AMI-CS, whereas greater benefit was observed in those with mechanical circulatory support. Trial sequential analysis indicated that the cumulative Z-curve for hypothermia did not cross the boundary for benefit, nor the futility boundary, suggesting that current evidence remains inconclusive and underpowered. In this meta-analysis, therapeutic hypothermia appeared safe but failed to show a significant reduction in all-cause mortality in patients with CS, albeit with very low certainty of evidence. Larger RCTs are warranted to clarify its clinical utility.