A new review summarizes the natural history of cardiomyopathies presenting with atrial fibrillation and the importance of managing underlying pathologies.

Patients with cardiomyopathy and heart failure (HF) also are more likely to have atrial fibrillation (AF). Current clinical guidelines classify AF as paroxysmal, persistent, longstanding persistent, or permanent, and treatment guidelines focus on rate and rhythm control rather than managing underlying pathogenic mechanisms. A review published online on February 15, 2014, in Heart Failure Reviews summarizes the natural history of cardiomyopathies presenting with AF, and the importance of managing underlying pathologies.
Many researchers now believe that the patient’s underlying myocardial substrate is an important driver of cardiac disease development, progression, and maintenance when it includes AF at presentation. AF may reflect specific underlying cardiomyopathy and explain why some AF cases are refractory to treatment and associated with poor prognosis.
The review authors urge diagnosticians to consider underlying genetic predisposition in patients with a family history of cardiomyopathy, severe ventricular disease at young ages, or cardiomyopathy with multi-system involvement. These histories or presentations demand genetic testing. They also indicate that “lone AF’’ and rapidly progressing tachyarrhythmia may indicate isolated atrial cardiomyopathy.
Patients with rapidly progressive AF in the absence of structural heart disease and other risk factors need cardiac magnetic resonance imaging (MRI). So do patients with longstanding persistent AF before they undergo catheter ablation of AF. An MRI can help determine the degree of fibrosis.
The authors’ recommendations, presented in tabular form, cover history-taking, diagnostics, and management. They stress that when cardiomyopathy presents with AF, it requires a broad diagnostic workup. They recommend following HF guidelines to optimize hemodynamics in patients with AF and acutely decompensated HF. They also present recommendations for patients with hypertrophic cardiomyopathy and paroxysmal AF. Finally, they remind clinicians that catheter ablation of AF in patients with extensive atrial fibrosis or isolated atrial cardiomyopathy may provide no benefit.

Ms. Wick is a visiting professor at the University of Connecticut School of Pharmacy and a freelance writer from Virginia.