Adjunctive RFA increases rate of sinus rhythm restoration

A study published in JAMA has demonstrated that left atrial radiofrequency ablation (RFA) for continuous atrial fibrillation during mitral valve surgery increases the rate of sinus rhythm restoration, improving patient exercise capacity.Atrial fibrillation frequently contributes to symptoms and morbidity in patients with mitral valve disease. There is growing interest in restoration and maintenance of sinus rhythm using a surgical approach in conjunction with pharmacological therapies. Specifically, the RFA of the left atrium is becoming more common; however, its efficacy has not been tested in an adequately powered randomised trial. Doukas et al. evaluated left atrial RFA during mitral valve surgery for treatment of continuous atrial fibrillation in patients with severe valvular heart disease.Of 101 consecutive patients referred for mitral valve surgery, 97 were randomly assigned to undergo surgery and RFA of the left atrium (n = 49) or surgery alone (controls; n = 48). The primary end point was the presence of sinus rhythm at 12 months and secondary end points included patient functional status and exercise capacity, left atrial contractility, and left atrial and left ventricular dimension and function and plasma levels of B-type natriuretic peptide (BNP).At 12 months, sinus rhythm was present in 44% of RFA patients and in 4.5% of controls. Restoration of sinus rhythm in the RFA group was accompanied by a greater improvement in mean shuttle-walk distance compared with controls (+94 m versus +48 m, respectively; p0.003). There was also a greater reduction in the plasma level of B-type natriuretic peptide in the RFA group compared with controls (-104 fmol/mL versus -51 fmol/mL, respectively; p=0.03). Similar rates of post-operative complications and deaths were observed between RFA patients and controls.Within the RFA group, patients converting to sinus rhythm achieved significantly longer shuttle-walk distance than their counterparts remaining in atrial fibrillation, suggesting that sinus rhythm restoration in patients undergoing successful correction of mitral regurgitation further improves functional status. Furthermore, evidence of recovery of left atrial contractility was observed in 86% of patients who regained sinus rhythm and could count for the improvements in cardiac dimensions and function and the better exercise capacity following RFA. Thus, this study demonstrated that left atrial RFA for continuous atrial fibrillation during mitral valve surgery significantly increased the prevalence of sinus rhythm at 12 months without an increase in peri-operative morbidity, which results in improved exercise capacity.In a related editorial Sundt and Gersh note that the trial by Doukas et al. is "an important step, but whether patients who do not have indications for valve surgery should undergo minimally invasive surgical maze procedures remains to be determined."Reference...