Development of an Acute Coronary Syndrome-Cardiogenic Shock Risk Score for 30-day Mortality From the Victorian Cardiac Outcomes Registry (VCOR ACS-CS Risk Score).

INTRODUCTION: Acute coronary syndrome-cardiogenic shock (ACS-CS) confers a 30-day mortality rate of ~50%. A simple bed-side risk score for 30-day all-cause mortality may aid in rapid prognostication in these high-risk patients.

METHODS: We analyzed data from consecutive patients with ACS-CS enrolled in the Victorian Cardiac Outcomes Registry (VCOR), a state-wide procedure-based clinical quality registry, between 2013 and 2021. Internal validation was performed in 1000 bootstrapped samples to derive variables that were in > 60% of models for the prediction of 30-day mortality. Model performance was evaluated using C-statistic, and Hosmer Lemeshow (HL) statistic.

RESULTS: Of 1564 patients with ACS-CS undergoing percutaneous coronary intervention (PCI), 1403 presented with ST-elevation myocardial infarction (STEMI) and 161 with non-STEMI. Age was 66 ± 13 years, and 74% were males. In-hospital and 30-day mortality rates were 42% and 45%. Selected predictors of 30-day mortality included age (odds ratio (OR) 1.4 [1.3, 1.6] per 10 year increase), female sex (OR 1.4 [1.1, 1.8]), diabetes (OR 1.5 [1.2, 2.0]), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (OR 2.2 [1.3, 3.5]), <60 mL/min/1.73 m2 (OR 1.5 [1.1, 2.0], left ventricular ejection fraction < 35% (OR 4.6 [3.5, 6.1]), out-of-hospital cardiac arrest (OR 2.3 [1.8, 3.1]), pre-procedural intubation (OR 2.1 [1.6, 2.7], mechanical circulatory support (OR 1.5 [1.1, 2.1]), STEMI (OR 2.6 [1.7, 3.8]), and multivessel PCI (OR 1.5 [1.1, 2.1], all p < 0.01). Internal validation of 1000 bootstrapped samples resulted in 15 clinical and procedural variables, which demonstrated excellent fit and performance (C-statistic = 0.8, HL p = 0.44) for the prediction of 30-day mortality.

CONCLUSION: A risk score incorporating only peri-procedural (clinical and procedural) variables accurately stratified 30-day mortality risk among patients with ACS-CS who underwent PCI. Further studies are required to externally validate the VCOR ACS-CS risk score, however, its simplicity potentially facilitates translation into clinical practice.