Atrial fibrillation management during septal myectomy for hypertrophic cardiomyopathy: A systematic review

Abstract

Introduction Atrial fibrillation is common in patients with hypertrophic cardiomyopathy, and significantly impacts mortality and morbidity. In patients with atrial fibrillation undergoing septal myectomy, concomitant surgery for atrial fibrillation may improve outcomes. Methods A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All studies reporting the outcomes of combined septal myectomy and atrial fibrillation surgery were included. Results A total of 10 observational studies were identified, including 644 patients. Most patients had paroxysmal atrial fibrillation. The proportion with prior unsuccessful ablation ranged from 0 to 19%, and preoperative left atrial diameter ranged from 44 ± 17 to 52 ± 8 mm. Cox–Maze IV (n = 311) was the most common technique used, followed by pulmonary vein isolation (n = 222) and Cox–Maze III (n = 98). Patients with persistent or longstanding atrial fibrillation more frequently received Cox–Maze III/IV. Ranges of early postoperative outcomes included: mortality 0 to 7%, recurrence of atrial tachyarrhythmias 4.4 to 48%, cerebrovascular events 0 to 1.5%, and pacemaker insertion 3 to 21%. Long-term data was limited. Freedom from atrial tachyarrhythmias at 1 year ranged from 74% to 96%, and at 5 years from 52% to 100%. Preoperative predictors of late atrial tachyarrhythmia recurrence included left atrial diameter >45 mm, persistent or longstanding preoperative atrial fibrillation and longer atrial fibrillation duration. Conclusion In patients with atrial fibrillation undergoing septal myectomy, the addition of ablation surgery adds low overall risk to the procedure, and likely reduces the risk of recurrent atrial fibrillation in the long term. Future randomised studies comparing septal myectomy with or without concomitant AF ablation are needed.

An overview of the treatments for hypertrophic cardiomyopathy

“…In patients with preoperative lesions of the mitral valve itself, intervention of the mitral valve and its appendages is performed in conjunction with hypertrophic myocardial resection ( 15 ). For patients with concomitant AF, it is recommended to combine septal myectomy with the AF Maze procedure ( 38 ). The surgeon's experience and that of the entire surgical team have a significant impact on the outcome of a septal myectomy ( 10 ).…”

Ventricular Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy (Analysis Spanning 60 Years Of Practice): AJC Expert Panel

“…In those HCM patients with a history of paroxysmal AF, some surgeons have combined myectomy with operative ablation procedures (Cox-Maze III or IV, or pulmonary vein isolation) [85][86][87] (Figure 4). In one center, an adjunctive bi-atrial Cox-Maze IV procedure was performed with myectomy in 100 patients, 85 resulting in effective relief of outflow obstruction and refractory HF symptoms, as well as providing freedom from AF episodes: 91%, 73%, 49% at 1, 5, and 10 years postoperatively, including 55% of patients without symptomatic AF for up to 8 years (Figure 4).…”