The CHA ₂ DS ₂ -VASc score has become a standard part of the evaluation of all patients with atrial fibrillation since its introduction into clinical practice and its replacement of the CHADS score [ 1 ]. It has been incorporated into virtually every Atrial Fibrillation Guideline, and its utility for estimating the risk of stroke is widely accepted [ 2 3 4 ]. In this issue of the journal, Borovac et al. transform the CHA ₂ DS ₂ -VASc score and extend its usefulness [ 5 ]. They use the score to confirm and extend the observations made by several other groups and apply the CHA ₂ DS ₂ -VASc score to predict death and peri-procedural events for inpatients with acute coronary syndrome (ACS) and atrial fibrillation undergoing percutaneous coronary intervention (PCI).