Mortality Predictors and In-Hospital Outcomes in High Killip Class STEMI Patients: Insights from a Tertiary Cardiac Center

Objectives: Patients with ST elevation myocardial infarction (STEMI) presenting with high Killip class face an elevated risk of adverse outcomes. This study aimed to evaluate the in-hospital outcomes and identify predictors of mortality in such patients admitted to the intensive care unit (ICU) after primary percutaneous coronary intervention (PCI) at a tertiary cardiac center in a low-middle income country. Methodology: A descriptive cross-sectional study was conducted in the ICU of a tertiary cardiac center in Pakistan. The study included adult patients (≥18 years) with high Killip class (≥III) at presentation, diagnosed with STEMI, and admitted to the ICU following primary PCI. Patients were monitored for adverse events, and mortality predictors were analyzed using binary logistic regression. Results: A total of 125 patients were enrolled, with a predominance of males (62.4%) and a mean age of 61.7 ± 10.6 years. Most patients presented with Killip Class III (76%). The mean SOFA and APACHE II scores at ICU admission were 6 ± 2.9 and 13.1 ± 6.0, respectively. The in-hospital mortality rate was 28.0% (35/125). Multivariable analysis identified sub-optimal post-procedure TIMI flow (<III) and higher SOFA score as independent predictors of mortality, with adjusted odds ratios (ORs) of 11.08 [95% CI: 2.39-51.27] and 1.47 [95% CI: 1.11-1.94], respectively. Conversely, placement of an intra-aortic balloon pump was associated with a significantly reduced mortality risk (adjusted OR 0.07 [95% CI: 0.01-0.38]). Conclusion: The study found a high in-hospital mortality rate among STEMI patients with high Killip class. Sub-optimal post-procedure TIMI flow and elevated SOFA scores were significant predictors of mortality, whereas intra-aortic balloon pump placement was associated with improved survival.