ORBI Risk Score as a predictor of in-hospital mortality and long-term outcomes in patients with ST-segment elevation myocardial infarction

Abstract

Funding Acknowledgements Type of funding sources: None. Introduction ST-elevation myocardial infarction (STEMI) encompasses a heterogeneous group of patients with distinct prognoses. In worse clinical scenarios with the development of cardiogenic shock (CS), mortality may ascend to 40%. Observatoire Régional Breton sur l'Infarctus risk score (ORBIs) was developed to predict the development of in-hospital CS in patients with STEMI treated with primary percutaneous coronary intervention (PCI). Aim To validate ORBI score as a predictor of in-hospital mortality (IHM) and long-term outcomes in STEMI. Methods Retrospective analysis of 296 patients admitted for STEMI and treated with PCI. Patients presenting with CS at admission were excluded. ORBIs evaluates the presence of 11 variables: age >70 years, prior stroke/transient ischemic attack, cardiac arrest upon entry, anterior STEMI, first medical contact-to-PCI delay >90 min, Killip class, heart rate >90/min, a combination of systolic blood pressure <125 mmHg and pulse pressure <45 mmHg, glycemia>10 mmol/L, culprit lesion of the left main coronary artery, and post-PCI thrombolysis in myocardial infarction flow grade <3. The score derived from these variables allowed the classification of patients into four risk categories: low (0-7 points), low-to-intermediate (8-10 points), intermediate-to-high (11-12 points), and high (≥13 points). The Mann-Whitney U test was used for median comparison between groups. Kaplan-Meier survival plots were used to evaluate the predictive power of ORBIs on INM and on 12-month cardiovascular events (12MH). Results Mean age was 63,9±13 years; 75% were men. 11% had a history of coronary artery disease, and 8% had been submitted to PCI previously. Mean LVEF was 54±12%. 69% had radial artery access. Left anterior descending artery disease was present in 68% of patients. Mean time since beginning of symptoms and hospital admission was 369±492 minutes. Mean duration of hospitalization was 5,68±3,5 days. ORBIs was calculated, and the population was divided into 2 groups: 45% were included in low and low to intermediate risk group (LR) (n=134), and 55% in intermediate to high- and high-risk group (HR). IHM was 3,7%. HR ORBIs was significantly associated with in-hospital mortality (6,2% vs 0,7%; p<0,01; OR 8,8 IC 95% 1,1;69,7). HR ORBIs was also significantly associated with long-term events (mortality and hospitalizations) (15% vs 6%; p<0,01). In univariate analysis, HR group showed significantly different LV ejection fraction (53,6±14,3 vs 61,0±13,1; p<0,01), troponin I at admission (33,3±94,12 vs 15,2±41,9; p<0,01), BNP (424,9±533,4 vs 194,1±170,1; p<0,01), duration of hospitalization (6,1±3,1 vs 5,2±3,9; p<0,01) and age (68,2±12,7 vs 58,9±11,5; p<0,01). Conclusion Higher ORBIs is associated with increased mortality in patients with STEMI. ORBIs may be a simple predictive model for short and long-term mortality and cardiovascular events in STEMI patients.