Does diffuse irrigation result in improved radiofrequency catheter ablation? A prospective randomized study of right atrial typical flutter ablation

A mesh-type flexible tip catheter vs a contact force catheter for catheter ablation of atrial fibrillation: A prospective nonrandomized 1:1 matched study

INTRODUCTION

Mesh-type flexible tip (MFT) catheters allow clinicians to safely generate large radiofrequency lesions during catheter ablation of atrial fibrillation (AF), while contact force (CF) catheters provide better catheter-tissue contact. We compared the clinical outcomes of catheter ablation of AF using MFT and CF catheters in a prospective, nonrandomized manner.

METHODS

We prospectively assigned 217 patients with AF (paroxysmal AF 73.5%; male 69.1%; 59.9 ± 10.7 years old) at a 1:1 ratio to ablation with MFT catheters (FlexAbility) or CF catheters (TactiCath). The primary endpoint was AF recurrence after a single procedure; the secondary endpoint was a response to antiarrhythmic drugs.

RESULTS

After a mean follow-up of 22.3 ± 4.4 months, the clinical recurrence rate did not significantly differ between the two study groups (29.7% vs 30.2%; P = .941) (log-rank P = .838). The recurrence rate for atrial tachycardias (30.3% vs 9.7%; P = .035) and cardioversion rates (8.1% vs 1.9%; P = .024) were higher in the MFT group than CF group. At the final follow-up, sinus rhythm was maintained without antiarrhythmic drugs in 57.7% of the MFT group and 40.6% of the CF group (P = .010). No significant difference was found in the major complication rates between the two groups (0.9% vs 5.7%), although the ablation time was significantly longer in the MFT group (4192.1 ± 1080.2  vs 3583.8 ± 977.2 seconds; P < .001).

CONCLUSION

MFT and CF catheters had similar effectiveness in achieving AF rhythm control during catheter ablation, and there was no significant difference between the two catheters with regard to overall safety.

Clinical experience with contact-force and flexible-tip ablation catheter designs

PURPOSE

Lesion formation is a critical determinant of technical and clinical success of pulmonary vein isolation. Different catheter designs aim to enhance tissue contact during ablation to enable optimized lesion formation. We analyzed procedural characteristics and predictors of clinical success in patients ablated with three different contemporary ablation catheters.

METHODS

Two hundred sixty-eight sequentially included patients receiving pulmonary vein isolation (PVI) with conventional (n = 122), contact-force (n = 96) and flexible-tip (n = 60) catheters were followed for a median of 14.1 months with 7d-Holter-monitoring and TTE at 3, 6, 12, and 24 months. Baseline characteristics and follow-up times were homogeneous across all groups.

RESULTS

Multivariable Cox proportional hazard regression for arrhythmia recurrence demonstrated a favorable hazard ratio for contact-force and flexible-tip catheters vs. conventional open irrigation catheters. Procedure time and fluoroscopy time were shorter for contact-force and flexible-tip catheters versus conventional catheters, but equal between. Linear lesions were applied in 58 % of contact-force and 66 % of flexible-tip cases, and CFAEs were targeted in 26 % of either.

CONCLUSIONS

Our non-randomized prospectively collected data do not show a difference in observed procedure characteristics and in clinical outcome for flexible-tip versus contact-force catheter designs, while both display improved performance against conventional open irrigated-tip catheters. Linear lesions and CFAEs ablation were not associated with improved arrhythmia-free survival.