Catheter ablation of the cavotricuspid isthmus in patients with atrial flutter: predictors of long-term outcomes

Abstract

Background: Predictors of long‑term outcomes and an optimal catheter set for ablation of the cavotricuspid isthmus in patients with atrial flutter (AFL) are not well known.

Aims: This study aimed to identify predictors of clinical events following ablation.

Methods: We studied 741 patients (mean [SD] age, 62.2 [10.8] years; 248 women) who were followed for a mean (SD) time of 4.4 (2.7) years. The 2- versus 3‑electrode approach and clinical predictors ofclinical events during follow‑up were analyzed.

Results: The 2‑electrode approach was faster (mean [SD] time, 62.5 [30.3] vs 101.4 [51] min; P < 0.001), associated with shorter fluoroscopy time (13.1 [9.3] vs 20.3 [12.4] min; P < 0.001), cost‑effective (8.29 [2.82] vs 11.89 [2.51] units; P < 0.001), and more effective (92.1% vs 86.1%; P = 0.012). The independent predictors of AFL recurrence were: calcium blocker use (hazard ratio [HR], 3.24; 95% CI, 1.64–6.4), mitral valve disease (HR, 1.82; 95% CI, 1.12–2.95), previous stroke and/ or TIA (HR, 2.38; 95% CI, 1.21–4.65), pulmonary artery dilatation (HR, 3.94; 95% CI, 1.22–12.73), and previous pulmonary embolism (HR, 3.77; 95% CI, 1.14–12.43); of atrial fibrillation (AF): previous AF (HR, 6.054; 95% CI, 4.58–8), left atrial enlargement (HR, 1.43; 95% CI, 1.12–1.81), number of antiarrhythmic drugs used (HR, 1.16; 95% CI, 1.05–1.28), and mitral valve disease (HR, 1.28; 95% CI, 1.04–1.58); of pacemaker implantation: tachycardia‑bradycardia syndrome (HR, 6.17; 95% CI, 3.16–12.05), previous second-/third‑degree atrioventricular block (HR, 29.4; 95% CI, 7.37–117.28), centrally acting hypotensive drugs (HR, 29.55; 95% CI, 6.14–142.25), aortic dilatation or aneurysm (HR, 2.58; 95% CI, 1.06–6.3), a labile international normalized ratio (HR, 3.45; 95% CI, 1.72–6.93), left bundle branch block (HR, 4.7; 95% CI, 1.49–14.82), the shortest R‑R interval during AFL (HR, 1.003; 95% CI, 1.001–1.005), previous cardiac surgery (HR, 2.69; 95% CI, 1.27–5.7), and aortic valve disease (HR, 2.22; 95% CI, 1.08–4.59).

Conclusion: Ablation of cavotricuspid isthmus with a minimal number of electrodes is safe and effective. Specific predictors of clinical events during long‑term follow-up can be determined.