Atrial tachyarrythmias after radiofrequency pulmonary vein isolation of atrial fibrillation: long term follow up

Abstract

SUMMARY A trial fibrillation is the most common sustained cardiac rhythm disturbance, increasing in prevalence with age. It has been well established that pulmonary vein (PV) triggering or driving is the dominant mechanism for paroxysmal atrial fibrillation (AF), and circumferential PV isolation (CPVI) is the main approach for AF elimination. Despite the sophisticated technology involved in AF ablation therapy, however, AF recurrence may be observed either in the early period after PVI or during long-term follow-up. In some patients, temporal exacerbation of AF is observed during the early period after PVI. Furthermore, it is not clearly defined when the early periods ends and when the late period starts. Previously, AF recurrences during the first weeks after PVI were treated as a non significant factor, but nowadays they are regarded to have an impact on long-term PVI failure. Aim of the study: This study aims to identify the incidence of atrial tachyarrythmias, their characteristics, predictors of occurrence, and their influence on recurrence of AF within 1 year after PVI. Methods: This study is a prospective study which was carried on 36 (thirty six) patients presenting to the cardiology department at Ain Shams university hospitals with paroxysmal or persistent atrial fibrillation for radiofrequency catheter ablation from the period from September 2013 to December 2014, Follow up for the patients was done for a duration of one year after the procedure to detect long term success rate including the following data ,History taking as regard recurrence of the symptoms ,Surface ECG was taken at 1 day, 7 days, 1 month, and 6 months after the procedure , Holter monitoring in patients with recurrent symptoms to evaluate any arrhythmic event, at 6 months and 1 year after the procedure ,Cases were asked to record their ECG when symptomatic. Any episode of symptomatic or asymptomatic atrial tachyarrhythmia that lasted more than 30 seconds documented with ECG or Holter monitoring was considered a recurrence after the first 3 months post ablation. Results: The mean age for the study cohort was 45.3 years (± 11.4 SD), with males representing 72.2% (n=26) of the patients & females represent 27.8% (n=10).The study included 19 hypertensive patients (52.8%), 6 smokers (16.7%), 5 diabetic patients (13.9%) and only one patient with HCM (2.8%).The patients included in the study were suffering from atrial fibrillation for a mean of 43.5 months (± 27 SD) with a mean frequency of 3.64 ± 1.18 times/month, with 34 patients graded as EHRA III (94.9%), only 13 patients had persistent AF (36%) while 23 patients (63.9%) had paroxysmal AF, with only 3 patients (8.3%) were having redo procedures. Regarding response to medical treatment before being candidate for the procedure 28 patients (77.8%) used one drug only before ablation while 5 patients (13.9%) used 3 drugs. As for the last ineffective drug before ablation, Amiodarone was the one in 16 patients (44.4%), while Propafenone was the one in 20 patients (55.6%) and Sotalol in only one patient (2.8%).The mean LVEF among the study cohort was 65.47% (± 3.07 SD), the left atrial dimension ranged from 32mm to 56mm with mean LAD 42.75mm (± 5.02 SD).Of the 36 patients included in the study, only 7 patients (19.4%) underwent AF ablation by segmental P.V.I. conventionally, whereas 29 patients (80.4%) underwent circumferential ablation using 3D-mapping with 6 patients (16.7%) having additionary ablation lines.The mean fluoroscopic time was 44.21 min. (±27.9 SD), while the mean procedural time was 167.36 min. (±30.69 SD).Both exit block & entrance block were achieved in all patients.Atrial arrhythmias occurred in 17 patients (47.2%) of them 13 patients (36.1%) had only one attack, 2 patients (5.6%) had 3 attacks and only one patient (2.8%) had 2 attacks, one patient (2.8%) had 4 attacks. During the blanking period , 22 patients (61%) took amiodarone as antiarrhythmic drug, 13 patients (36%) took propafenone & only one patient took sotalol.AF recurred in 3 patients (8.3%) after 3 months of follow up, 5 patients (13.9%) after 6 months and 12 patients (33.3%) at 1 year follow up.Of them only 9 patients were symptomatic, 7 patients responded to medical treatment and one patient had a redo procedure.