Surgical ablation in hypertrophic obstructive cardiomyopathy: What is the real deal?

Atrial fibrillation (AF) is the most common tachyarrhythmia in patients with hypertrophic obstructive cardiomyopathy (HOCM), with an estimated prevalence of approximately 20% [ [1] Choi Y.J. Choi E.K. Do Han K. et al. Temporal trends of the prevalence and incidence of atrial fibrillation and stroke among Asian patients with hypertrophic cardiomyopathy: a nationwide population-based study. Int. J. Cardiol. 2018; 273: 130-135 Abstract Full Text Full Text PDF PubMed Scopus (38) Google Scholar ]. AF is associated with malignant outcomes in patients with HOCM, with an increased risk of embolic stroke, heart failure, severe functional impairment and mortality [ [2] Rowin E.J. Hausvater A. Link M.S. et al. Clinical profile and consequences of atrial fibrillation in hypertrophic cardiomyopathy. Circulation. 2017; 136: 2420-2436 Crossref PubMed Scopus (147) Google Scholar ]. Furthermore, AF is poorly tolerated by patients with HOCM, with increased heart failure episodes, hemodynamic instability and impaired quality of life [ [3] Olivotto I. Cecchi F. Casey S.A. et al. Impact of atrial fibrillation on the clinical course of hypertrophic cardiomyopathy. Circulation. 2001; 104: 2517-2524 Crossref PubMed Scopus (637) Google Scholar ]. Nevertheless, concomitant surgical treatment of AF at the time of septal myectomy is rarely performed and clear/specific indications are lacking due to the limited evidence in the literature. The current European [ [4] Zamorano J.L. Anastasakis A. Borger M.A. et al. 2014 ESC guidelines on diagnosis and management of hypertrophic cardiomyopathy: the task force for the diagnosis and management of hypertrophic cardiomyopathy of the European Society of Cardiology (ESC). Eur. Heart J. 2014; 35: 2733-2779 Crossref PubMed Scopus (2984) Google Scholar ] and American [ [5] Ommen S.R. Mital S. Burke M.A. et al. 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: executive summary: a report of the American College of Cardiology/American Heart Association joint committee on clinical practice guidelines. J. Am. Coll. Cardiol. 2020; 76: 3022-3055 Crossref PubMed Scopus (81) Google Scholar ] guidelines provide a level IIa indication to surgical AF ablation in patients that require surgical myectomy, as “potentially beneficial for AF rhythm control”. However, which patients and how should they be surgically treated? More specifically, in whom should surgical AF ablation be performed (only patients with long-standing AF or also patients with paroxysmal AF) and what surgical strategy should be employed?