Late gadolinium enhancement as an independent predictor of atrial fibrillation in hypertrophic cardiomyopathy (HCM)

Atrial fibrillation (AF) is the most common arrhythmia observed in HCM, developing in approximately 20% of all cases, with an annual incidence of 1–3% per year. The risk of AF developing is 4–6 fold greater in HCM than in the general population. Its' development is associated with an increased risk of systemic thromoboembolism, heart failure and death. Myocardial fibrosis is an important risk factor for the development of atrial fibrillation as demonstrated in post mortem studies. Cardiovascular magnetic resonance (CMR) is the gold standard imaging tool to visualise replacement myocardial fibrosis in vivo. The presence of fibrosis has been shown to be an important predictor of cardiovascular morbidity and mortality in both ischaemic and dilated cardiomyopathies, and more recently an important predictor of arrhythmia as detected by Holter monitoring in HCM.