Objectiv:

Power controlled very high power short duration (vHPSD) radiofrequency-ablation (RFA) using 70watts for 5-7 seconds is highly efficient and safe while reducing procedure and RF time in pulmonary vein isolation (PVI). While the numbers of clinical thromboembolic events are comparable between HPSD and standard power (SD), little is known about the occurence of silent cerebral lesions (SCL) in these ablation modalities. We sought to compare the amount of SCL between vHPSD and standard ablation.

Method:

We randomized n=35 patients scheduled for PVI due to paroxysmal AF undergoing vHPSD (n=18) or SD ablation (n=13). All patients underwent cerebral MRI within 24-48h after ablation. Patients` characteristics are shown in table 1.

Cerebral MRI was performed using a 1,5 tesla device. In our protocol a T2-weighted axial fluid-attenuated inversion recovery sequence (FLAIR) (TI=2,5000ms, TR=9000ms, TE=125ms, slice thickness 4.0 mm, in-plane resolution: 0.9 x 0.9 x 4.0mm, flip angle 160°) and a diffusion-weighted echo-planar imaging sequence (DWI) (TR=3,700ms, TE 105ms, in-plane resolution: 1.2 X 1.2 X 6.0) were used. An additional apparent diffusion coefficient (ADC) map was obtained. 

Results:

None off the patients experienced clinical apparent thromboembolic complications. Overall, new SCLs were detected in n=4 patients (11.4 %) after AF ablation. New SCLs were detected in n=1 (5.3%) in the HPSD group and n=3 (18.8%) in the SD group (p=0.3). Procedural duration and RF time were significantly shorter in the HPSD group. In the HPSD ablation one tamponade occurred associated to transseptal puncture (prior to ablation). Procedural data and complications are shown in table 1. 

Conclusion:

HPSD ablation did not lead to a higher rate of SCL compared to SD ablation. Numerically, SD ablation showed more SCL in MRI without significance. Besides described safety regarding thromboembolic complications HPSD is also safe regarding findings of SCL in cMRI.