Stroke prediction with an adjusted R-CHA2DS2VASc score in a cohort of patients with a Myocardial Infarction

Introduction: A new risk stratification scheme incorporating the original CHADS2 score and renal function, entitled R(2)CHADS(2), was validated in the ROCKET-AF and ATRIA study cohorts.

Aims: Adjusting and validating a modified R-CHA2DS2VASc score as a predictor of ischaemic stroke and all-cause mortality in patients discharged following admission for a Myocardial Infarction (MI).

Materials and methods: Observational retrospective single-centre cohort study including 1711 patients admitted with MI and discharged alive. We tested the prognostic performance of R-CHA2DS2VASc, based on the original CHA2DS2VASc score with few modifications (addition of renal function parameters [glomerular filtration rate and urea], performance of a revascularization procedure and history of atrial fibrillation). R-CHA2DS2VASc was evaluated for its discriminative performance and calibration in the prediction of ischaemic stroke (primary endpoint), all-cause mortality and a composite endpoint of ischemic stroke plus all-cause mortality (secondary outcomes) during follow-up.

Results: R-CHA2DS2VASc score's areas under the curve (AUC) for the occurrence of primary and secondary outcomes were: Ischaemic stroke: AUC 0.717 ± 0.031, p<0.001 (vs. 0.681 ± 0.043 for CHA2DS2VASc, p=0.290); all-cause mortality during follow-up: AUC 0.811 ± 0.014, p<0.001 (vs. 0.782 ± 0.019 for GRACE, p=0.245); composite endpoint: AUC 0.803 ± 0.014, p<0.001. The integrated discrimination improvement index (IDI) and relative IDI for the primary endpoint were 0.015 and 28.2%, respectively, while the IDI and relative IDI for all-cause mortality were 0.13 and 72.1%, suggesting a large improvement in risk stratification. An R-CHA2DS2VASc score below 3 had a negative predictive value of 98.6% for the occurrence of ischaemic stroke.

Conclusions: The modified R-CHA2DS2VASc score has shown good calibration and high discriminative performance in the prediction of post-discharge ischaemic stroke and all-cause mortality. The inclusion of renal function in thromboembolic risk predicting schemes seems warranted.