Long-term risk of right coronary artery injury after catheter ablation of cavotricuspid isthmus-dependent flutter

Background: Radiofrequency ablation (RFA) of cavotricuspid isthmus (CTI)-dependent atrial flutter requires ablation of the tricuspid annulus overlying the right coronary artery (RCA). Although it is considered safe, reports of acute and subacute RCA injury in human and animal studies raise the possibility of late RCA stenosis.

Objective: The objective of this study was to compare the incidence and severity of angiographic RCA stenoses in patients who have undergone CTI RFA with a control group to assess the long-term risk of RCA damage.

Methods: A 2-center retrospective case-cohort study was performed including all patients from 2002 to 2018 undergoing atrial fibrillation (AF) with CTI ablation (CTI + AF) or AF ablation alone with subsequent coronary angiography (CAG). The AF alone group served as controls because of anticipated similarity of baseline characteristics. Coronary arteries that are anatomically remote to the CTI were examined as prespecified falsification end points. CAG was scored by a blinded observer.

Results: There were 156 patients who underwent pulmonary vein isolation with subsequent CAG (CTI + AF, n = 81; AF alone, n = 75) with no difference in baseline characteristics including age, sex, comorbidities, and medications. Mean time from ablation to CAG was similar (CTI + AF, 5.0 ± 3.7 years; AF alone, 5.4 ± 3.9 years; P = .5). The mid and distal RCA showed no difference in the average number of angiographic stenoses or lesion severity. In regression analysis, CTI ablation was not a predictor of RCA stenosis severity (P = .6). There was no difference in coronary disease at sites remote to the CTI ablation (P = NS for all).

Conclusion: There was no observed relationship between CTI RFA and the number or severity of angiographically apparent RCA stenoses in long-term follow-up.