P-WAVE TERMINAL FORCE IN LEAD V1-MORRIS INDEX AFTER CATHETER ABLATION: A STUDY IN ATRIAL FIBRILLATION AND TYPICAL ATRIAL FLUTTER PATIENTS

Introduction: P-wave terminal force in lead V1 (PTFV1, Morris Index) is a marker of atrial remodeling. We evaluated its role three months after atrial fibrillation (AF) or cavotricuspid isthmus (CTI) ablation. Methods: A total of 120 AF patients (46% persistent, 54% paroxysmal) and 58 CTI patients were analyzed. PTFV1 was measured pre-ablation and at three months. Abnormal PTFV1 was defined as ≥|0.04| mV·s. Patients were followed for 12 months. Endpoints were AF/AT recurrence in the AF cohort and new AF in the CTI cohort. Results: In the AF cohort, recurrence occurred in 31%. Abnormal 3-month PTFV1 predicted higher recurrence (46% vs. 21%; HR 2.05, 95% CI 1.22–3.46). Addition of PTFV1 improved AUC from 0.67 to 0.76. In the CTI cohort, new AF occurred in 15%, but abnormal PTFV1 was not predictive (OR 1.8, 95% CI 0.8–4.2). Lead II P-wave duration was significant. Conclusion: Three-month PTFV1 is a robust predictor of AF recurrence after ablation. Its role in CTI ablation is limited.