Abstract
BACKGROUND: Cardiogenic shock (CS) is the leading cause of death in patients hospitalized with Acute Coronary Syndrome (ACS) despite aggressive treatment and recent advances in management. The incidence of CS and predictors of survival in Pakistani population are not well studied. The primary objective of our study was to determine the incidence of CS in ACS patients and assess the management patterns and predictors of in-hospital and follow-up mortality at Tabba Heart Institute. METHODS: We collected retrospective data on ACS patients from Institutional Chest Pain MI registry from July 2013 to June 2020, including all patients who developed CS at the time of arrival in Emergency Department or during their hospital stay. Patients with shock in the absence of significant coronary artery disease and patients developing CS complicated by mechanical cardiac procedures were excluded. Multivariable logistic stepwise regression model was applied to identify significant predictors of survival among revascularized and conservatively treated groups, using SPSS version 22.0. Follow-up was sought for patients discharged alive, for mortality and adverse cardiac events. RESULTS: Out of a total of 30,215 ACS patients, 456 (1.51%) were diagnosed with CS in 2013, with a decreasing incidence to 1.1% seen till 2016 and later rising again to more than 1.8% in 2020. Mean age at presentation was 60.9 ± 11.1 years, 76.1% being male. 383 (84%) patients were revascularized [29 CABG only, 342 PCI only, and 12 patients had PCI followed by CABG]. Significantly lower morality was observed when comparing revascularized group as compared to conservative treatment group (44.4% vs. 82.2%, p-value < 0.001), whereas mortality within the revascularized group was 14.6%. The major predictors of in-hospital mortality in the overall cohort included no revascularization, diabetes history, cardiac arrest before catheterization, STEMI, > 2 vasopressors used, persistent shock status, multi-vessel disease, and use of IABP. The median follow-up time of 208 out of 226 (92%) survived patients was 17 months (IQR 7–33 months). There were 39 (18.8%) events, including MI, death, and need for revascularization reported, while 23 (11.0%) were deceased. CONCLUSION: Cardiogenic shock constitutes high mortality despite early invasive approaches of revascularization, underscoring the need for risk stratification using the key predictors to improve patient outcomes through targeted interventions and resource optimization.