Total ischemia time and in-hospital survival in STEMI-related cardiogenic shock: the critical impact of reperfusion delay

Background Despite advances in reperfusion therapies, cardiogenic shock (CS) remains the leading cause of mortality in patients with ST-segment elevation myocardial infarction (STEMI). While early revascularization via percutaneous coronary intervention (PCI) is the gold standard, the specific impact of total ischemia time (TIT) on in-hospital survival in this high-risk population requires further characterization. Methods We conducted a retrospective observational study at a tertiary cardiovascular center (2007–2025). A total of 512 adult STEMI patients complicated by CS who underwent PCI were analyzed. The primary objective was to assess the association between TIT (defined as symptom onset to wire crossing) and in-hospital mortality. Natural cubic splines and Cox proportional hazards models were utilized to identify risk thresholds and independent predictors. Results Of the 512 patients, 59% (n=302) had a TIT ≤402 minutes, while 41% (n=210) had a TIT ≥402 minutes. Patients with a TIT ≤402 minutes demonstrated a 32.5% lower risk of in-hospital mortality compared to those with longer delays (HR 0.68; 95% CI 0.50–0.91; p=0.010). In a continuous analysis, every 60-minute increase in TIT was associated with a 3.3% increase in the relative risk of death (adjusted HR 1.033; 95% CI 0.980–1.089). Other independent predictors of mortality included advanced age (HR 1.25 per 10-year increase), diabetes mellitus (HR 2.22), and higher SCAI shock stages (specifically stages D and E). Conclusion In STEMI patients presenting with cardiogenic shock, a total ischemia time exceeding 402 minutes is a critical independent predictor of in-hospital mortality. These findings emphasize the imperative need to optimize systems of care and minimize system delays, as every minute saved directly translates into improved survival for this critically ill population.