Refining prediction of stroke in sinus node dysfunction patients without atrial fibrillation using a P-combined score: a multi-centre study.

By screening the risk factors of ischaemic stroke for isolated sinus node dysfunction (sinus node dysfunction without atrial fibrillation), we developed and validated a new scoring system­P-combined score, which is a combination of an abnormal P-wave terminal force in electrocardiogram-lead V1 (PTFV1) and the CHA2DS2-VASc score. We constructed the P-combined score in the following way: abnormal PTFV1 (2 points), age (1 point for 65­74 years and 2 points for ≥75 years), sex (1 point for female), congestive heart failure (1 point), hypertension (1 point), diabetes mellitus (1 point), vascular disease (1 point), and thrombotic event (2 points). Based on our analysis, we found that the P-combined score showed a strong performance (with a C-statistic of 0.716 for 5 years), which was better than the CHA2DS2-VASc score (C-statistic of 0.678 for 5 years). We also found that the performance of the P-combined score was rigorous in an independent cohort from two external centres (with a C-statistic of 0.808 for 5 years) and outperformed the CHA2DS2-VASc score (C-statistic of 0.747 for 5 years).