Shock Index-Creatinine as a Predictor of In-Hospital Clinical Outcomes in Patients with Anterior Wall ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention.

Abstract

Background: Early risk stratification in ST-segment elevation myocardial infarction (STEMI) is essential but established scores such as TIMI and GRACE require multivariable computation. The Shock Index-Creatinine (SIC) is a simpler bedside alternative, yet Indian data are sparse.

Objective: To assess whether admission SIC predicts in-hospital adverse events in anterior wall STEMI patients undergoing primary percutaneous coronary intervention (PCI).

Methods: Two hundred consecutive patients with anterior wall STEMI undergoing primary PCI at a tertiary care centre in northern India were prospectively enrolled over 12 months. SIC was computed at admission as (Shock Index × 100) - Cockcroft-Gault creatinine clearance. The primary outcome was in-hospital death; secondary outcomes were heart failure, cardiogenic shock, contrast-induced acute kidney injury (CI-AKI), and life-threatening ventricular arrhythmia. Discrimination was assessed by the area under the receiver operating characteristic curve (AUC).

Results: The cohort was 73.0% male with a mean age of 54.5 years; in-hospital mortality was 10.0% (n = 20). Admission SIC was markedly higher in non-survivors than survivors (82.0 ± 42.4 versus -20.1 ± 19.4; p < 0.001). AUCs were 0.992 for mortality and cardiogenic shock, 0.971 for CI-AKI, 0.909 for ventricular arrhythmia, and 0.907 for heart failure (all p < 0.001). A SIC ≥ 20 predicted death with 95.0% sensitivity and 98.9% specificity.

Conclusions: In this Indian cohort, admission SIC was a powerful bedside predictor of adverse in-hospital events after primary PCI for anterior wall STEMI. The unusually high discriminative performance requires external validation in larger multicentre populations before routine clinical adoption.