GRACE score for risk stratification and completeness of revascularization in older patients with myocardial infarction

Abstract

Background: The GRACE score is a well established tool for predicting mortality outcomes in patients with myocardial infarction (MI). However, its prognostic role and interaction with revascularization strategies in older patients with MI remain unclear. This study aimed to assess whether the GRACE score was predictive of adverse events in the FIRE trial cohort and whether the benefits of complete revascularization were consistent across the spectrum of the GRACE score.

Methods: The FIRE trial randomized 1445 patients aged 75 years or older with MI and multivessel coronary artery disease to receive either culprit-only or complete revascularization. In this subanalysis, patients were stratified according to GRACE score tertiles: the first tertile (GRACE 92.6-128.0), the second tertile (GRACE 128.1-146.5), and the third tertile (GRACE 146.6-236.0). The primary endpoint was all-cause mortality at 1 year. Other key endpoints included cardiovascular death and a composite of cardiovascular death or MI at 1 year.

Results: According to GRACE score tertiles, 487 patients were in the first tertile (33.7%), 477 in the second tertile (33.0%), and 481 in the third tertile (33.3%). Patients in the third tertile were more compromised in terms of cardiovascular risk factors and comorbidities. At 1 year, all-cause mortality was significantly higher in the third tertile (P < 0.0001), as well as cardiovascular death (P < 0.0001) and the composite of cardiovascular death or MI (P < 0.0001). However, the effect of physiology-guided revascularization did not differ across GRACE score tertiles (P for interaction > 0.05 for all the outcomes of interest). Survival analysis confirmed that the GRACE score was significantly associated with increased all-cause mortality [hazard ratio 1.027, 95% confidence interval (95% CI) 1.021-1.033, P < 0.001], cardiovascular death (hazard ratio 1.031, 95% CI 1.023-1.039, P < 0.001), and the composite of cardiovascular death or MI (hazard ratio 1.020, 95% CI 1.013-1.026, P < 0.001). Again, no interaction was found between revascularization strategy and GRACE score (all P for interaction > 0.05). The best discriminative value of the GRACE score for all-cause mortality at 1 year was 137.

Conclusion: The GRACE score was confirmed to be predictive of adverse outcomes even in older MI patients. Physiology-guided complete revascularization was associated with benefit across the GRACE spectrum, suggesting that the GRACE score alone should not preclude this strategy in older patients with MI.

Keywords: GRACE score; acute coronary syndrome; complete revascularization; older patients; risk stratification.