James MacNamara, MD

Atrial fibrillation (AFib) is common in patients with hypertrophic cardiomyopathy (HCM) and, once identified, raises immediate questions about how aggressively to pursue rhythm control. In this segment, Mariko Harper, MD, MS, FACC, director of the Hypertrophic Cardiomyopathy Center of Excellence at Virginia Mason Franciscan Health, and James MacNamara, MD, a non-invasive cardiologist and HCM specialist at UVA Health, compare their screening habits and management philosophies before turning to what the pivotal cardiac myosin inhibitor (CMI) trials showed about AFib risk.

Atrial fibrillation (AFib) has long shadowed hypertrophic cardiomyopathy (HCM), but the arrival of cardiac myosin inhibitor (CMI) therapy has sharpened the question of what that relationship really means. As real-world experience with mavacamten and aficamten accumulates alongside pivotal trial data and new adolescent findings from SCOUT-HCM, clinicians are working to reconcile a safety signal that looks different depending on where they look.