Successful rhythm control of atrial fibrillation (AFib) was associated with improved secondary tricuspid regurgitation (STR) in patients with moderate-severe or severe STR, according to research published April 23 in JACC: Cardiovascular Imaging.

The retrospective cohort study by Jwan A. Naser, MBBS, and colleagues included 1,896 patients (median age, 79; 60% women) with AFib (33% paroxysmal, 67% persistent) and moderate-severe/severe STR who underwent serial echocardiography at Mayo Clinic sites between 2003 and 2023. STR etiologies included organic left-sided valve disease (26%), reduced LVEF or ischemic mitral regurgitation (24%), pulmonary hypertension (26%) and isolated STR (24%).

Rhythm control (including catheter ablation, cardioversion or use of antiarrhythmic medications for ≥30 days) was attempted in 367 (19%) patients over a median of 21 days. Those who underwent rhythm control were younger, more frequently men, and more often had a recent (<one year) diagnosis of AFib, paroxysmal AFib, low LVEF and right ventricular dysfunction. They less often had organic left-sided valve disease, pulmonary hypertension, diabetes and systemic hypertension.

Results over a median follow-up of 1.7 years showed that TR improved to ≤mild in 550 patients, and successful rhythm control was strongly associated with TR improvement (adjusted hazard ratio, 3.65; p<0.01). This association was consistent across STR etiologies, AFib type and chronicity, age, sex, obesity, left ventricular function, right ventricular remodeling and presence of pulmonary hypertension or significant mitral regurgitation.

AFib recurred in 210 patients (57%) who underwent rhythm control; predictors of recurrence included older age, persistent or chronic AFib, hypertension and lack of antiarrhythmic therapy.

Notably, the benefit of successful rhythm control may be more pronounced in patients with preserved LVEF and women, the latter of which the authors suggest may be due to "sex hormone-mediated inflammatory responses in [AFib], differences in fibroblast response to annular stress and leaflet adaptation, and structural differences in the mitral and tricuspid annuli," although further studies are needed.

"These findings suggest the importance of early aggressive rhythm control in patients with [AFib] and moderate-severe/severe STR and that rhythm control in these patients may be an additional effective strategy with a potential to avoid TR-targeted valve intervention, although this needs to be confirmed in randomized clinical trials," Naser et al., conclude.