Impact of hybrid procedure on P wave duration for atrial fibrillation ablation

AIM

Hybrid procedure (HP) involves epicardial isolation of pulmonary vein and posterior wall of left atrium, and endocardial checking of lesions and touchups (if needed). We aimed at observing the effect of hybrid procedure on P wave duration (PWD), calculated automatically from surface ECG leads at start and end of HP, and also for relationship to atrial fibrillation (AF) recurrence at 9 months.

METHODS

Forty-one patients (32 male; mean age, 58.4 ± 9.5 years) underwent HP, as first ever ablation. A new automated method was used for P wave segmentation and PWD estimation from recognizable P waves in ECG lead I or II before and after HP, based on fitting of each P wave by means of two Gaussian functions.

RESULTS

Overall, PWD was significantly decreased after procedure (104.4 ± 25.1 ms vs. 84.7 ± 23.8 ms, p = 0.0151), especially in persistent AF patients (122.4 ± 32.2 ms vs. 85.6 ± 24.5 ms, p = 0.02). PWD preprocedure was significantly higher in persistent than in paroxysmal patients (122.4 ± 32.2 ms vs. 92.5 ± 17.9 ms, p = 0.0383). PWD was significantly decreased after procedure in prior electrical cardioverted patients (106.7 ± 30.5 ms vs. 84.7 ± 23.1 ms, p = 0.0353). After 9-month follow-up of 40 patients, HP-induced PWD decrease was significant for the 12 persistent patients without recurrence (122.4.1 ± 35.3 ms vs. 85.6 ± 22.0 ms, p = 0.0210).

CONCLUSION

Preprocedure PWD was higher for persistent than paroxysmal patients. HP reduced PWD significantly. Nine-month follow-up suggests that HP is successful in restoring and maintaining sinus rhythm. To individualize AF therapy, AF type-based selection of patients may be possible before procedure. Automated analysis of PWD from surface ECG is possible.

Hybrid approach to atrial fibrillation ablation using bipolar radiofrequency devices epicardially and cryoballoon endocardially

OBJECTIVES

Bipolar radiofrequency (RF) devices are used epicardially by cardiac surgeons and cryoballoon endocardially by cardiac electrophysiologists for atrial fibrillation (AF) ablation, but in separate entities. The study's objective was to evaluate the feasibility and safety of combining an endocardial cryoballoon with epicardial bipolar RF ablation for the treatment of AF.

METHODS

A cohort of 7 patients with AF underwent a hybrid thoracoscopic surgical and endocardial ablation. To prevent bilateral sequential lung deflation in these patients with severe chronic obstructive pulmonary disease, the right pulmonary veins (PVs) were isolated using an epicardial bipolar RF clamp and the contralateral veins with an endocardial cryoballoon. A box lesion set was made epicardially using a bipolar RF pen.

RESULTS

Acutely, pacing manoeuvres proved a bidirectional block in all PVs in all patients. No complications were seen. A box lesion was made in 5 patients. During follow-up, 2 of them had AF recurrence: 1 was treated successfully with sotalol and another underwent redo RF catheter ablation with reisolation of the right inferior PV. At present, 6 of 7 patients are in sinus rhythm without any anti-arrythmic drugs during a follow-up of more than 40 ± 3 months.

CONCLUSIONS

A hybrid approach to AF ablation using a cryoballoon endocardially and a bipolar RF device epicardially is feasible and safe.

Management Of Pulmonary Vein Stenosis Following Catheter Ablation Of Atrial Fibrillation

There is limited literature available regarding PV (pulmonary vein) stenosis management. Starting from its incidence, subsequent follow up using imaging technologies to monitor the success and the way of managing different groups pose varied opinions. However, with newer technological advancements and better understanding of mechanism of the atrial fibrillation ablation, the incidence of PV stenosis secondary to catheter ablation is declining. This paper highlights the current trends and future of management of PV stenosis secondary to catheter ablation for atrial fibrillation.