Is prophylactic ablation of the cavotricuspid and peri-incisional isthmus justified in patients with postoperative atrial flutter after right atriotomy?

Background The two most common postoperative atrial flutter (AFL) circuits after right atriotomy are the cavotricuspid isthmus (CTI) dependent and the lateral, peri-incisional. We investigated whether radiofrequency ablation (RFA) of both circuits results in more favorable long-term outcomes. Methods Single-center retrospective cohort study of consecutive patients who underwent RFA of AFL after open-heart surgery. The effect of surgery type and RFA strategy on AFL recurrence was evaluated. Results One hundred and forty-two patients (mean age 64.5 +/- 12.7 years, 65.% male) were enrolled. Patients with right atrial (RA) flutter (n = 124) were divided into two groups based on the index RFA procedure: only one RA circuit was ablated (Group 1, n = 84, 67.7%) or both the CTI and the peri-incisional circuit ablated (Group 2, n = 40, 32.3%). The previous open-heart surgery was categorized based on the extension of the RA incision: limited (Type A) or extended (Type B) atriotomy. After a mean follow-up of 36 +/- 28 months, flutter recurrence was not different among patients with limited RA atriotomy (25% vs. 22% in Groups 1A and 2A, respectively, p = 1.0). However, after type B surgery, ablation of both AFL circuits was associated with a reduced recurrence rate (63% vs. 26% in Groups 1B and 2B, respectively, p = .002). Conclusions In patients with postoperative RA flutter after extended right atriotomy, ablation of both the CTI and the peri-incisional isthmus significantly reduces the AFL recurrence rate. Prophylactic ablation of both isthmi, even if not proven to support reentry, is reasonable in this population.