CHA₂DS₂-VASc Score and the Risk of Ventricular Tachyarrhythmic Events and Mortality in MADIT-CRT

Background: We hypothesized that multiple cardiovascular comorbidities, incorporated in the CHA₂DS₂-VASc score, may be useful in the assessment of ventricular tachyarrhythmias (VTAs) and mortality risk in heart failure (HF) patients. Methods and Results: We evaluated the association between the CHA₂DS₂-VASc score (dichotomized as high at the upper quartile [≥5] and further assessed as a continuous measure) and the risk of VTA and death among 1804 patients enrolled in MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy). A high CHA₂DS₂-VASc score (n=464; 26%) was inversely associated with the risk of any VTA (hazard ratio [HR]: 0.64; P=0.001), fast VTA >200 beats/min (HR; 0.51; P<0.001), and appropriate implantable cardioverter-defibrillator shocks (HR: 0.60; P<0.001). In contrast, a high score was directly correlated with mortality risk (HR: 1.92; P<0.001) and the risk of HF or death (HR: 1.60; P<0.001). Consistently, each 1-U increment in CHA₂DS₂-VASc was associated with a significant 13% (P=0.003) reduction in VTA risk but a corresponding 33% (P<0.001) increase in mortality risk. Patients with a high CHA₂DS₂-VASc score and left bundle-branch block derived a pronounced 53% (P<0.001) reduction in the risk of HF or death with cardiac resynchronization therapy with defibrillator versus implantable cardioverter-defibrillator–only therapy. Conclusions: Our findings suggest that a high CHA₂DS₂-VASc score can be used to identify patients with mild HF who have low VTA risk and high morbidity or mortality risk and may derive a pronounced clinical benefit from cardiac resynchronization therapy without a defibrillator. These data suggest a possible role for the CHA₂DS₂-VASc score in device selection among candidates for biventricular pacing.