Clin Res Cardiol (2022). https://doi.org/10.1007/s00392-022-02087-y
Magnetic resonance imaging assessment of lesions formation in very high-power short-duration pulmonary vein isolation
V. Sciacca1, T. Fink2, F. Nischik1, H. Körperich3, L. Bergau4, D. Guckel5, J. Eckstein3, M. Braun1, M. El Hamriti1, G. Imnadze2, M. Piran3, P. Sommer1, C. Sohns1
1Klinik für Elektrophysiologie/Rhythmologie, Herz- und Diabeteszentrum NRW, Bad Oeynhausen; 2Elektrophysiologie/ Rhythmologie, Herz- und Diabeteszentrum NRW, Bad Oeynhausen; 3Institut für Radiologie, Nuklearmedizin und Molekulare Bildgebung, Herz- und Diabeteszentrum NRW, Bad Oeynhausen; 4Herzzentrum, Klinik für Kardiologie und Pneumologie, Universitätsmedizin Göttingen, Göttingen; 5Klinik für Elektrophysiologie/ Rhythmologie, Herz- und Diabeteszentrum NRW, Bad Oeynhausen;

Background
Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation (AF). Ablation protocols using energy delivery with very high-power and short duration (vHPSD) were recently developed to optimize lesion formation.

Aims
The present study analyses procedural data of vHPSD ablation in AF patients and analyses characteristics of lesion formation based on magnetic resonance imaging (MRI).

Methods
Consecutive patients undergoing PVI by vHPSD ablation between 06/2021 and 03/2022 were prospectively enrolled. Ablation was conducted using a contact force sensing catheter allowing for vHPSD ablation with a temperature-controlled ablation mode with automatic adjustment of power and a targeted temperature of 60°C. Contact forces >10g and interlesion distances <6mm between ablation localizations were aimed for. The procedural endpoint was complete PVI with demonstration of entrance and exit block in all pulmonary veins (PVs). Thirty patients (50%) underwent cardiac MRI three months after PVI. Left atrial late gadolinium enhancement imaging was performed in all patients using a multi-transmit 3.0 Tesla system with dStream technology. Scar width and continuity of PV encirclement were analyzed. Scar width was defined as the distance between two maximally distant points, perpendicular to the ablation path. Complete PV encirclement was defined as a contiguous line of ablation tags or enhancement with >90 % encirclement of the PV ostium.

Results
Sixty patients were included into the study. Forty patients (66.7%) were male and mean age was 44.8 ±7.2 years. Initial type of AF was paroxysmal AF in 22 patients (36.7%), persistent AF in 32 patients (53.3%) and long-standing persistent AF in 6 patients (10%). Median CHA2DS2-VASC-Score was 2. Mean overall procedural duration was 66.5±14.8 minutes with a mean fluoroscopy time of 5.0±2.2 minutes. Mean ablation time for complete PVI was 4.7±0.9 minutes with a mean number of 69.9±14.2 radiofrequency applications. First pass isolation of right PVs was achieved in 51 patients (85%), of the left PVs in 37 patients (61.7%) and of both PVs in 34 patients (56.7%). Complete PVI at the end of the procedure was achieved in all patients. Periprocedural complications occurred in one patient (1.7%) who developed an aneurysm at puncture site which was managed conservatively. MRI analysis three months post ablation showed a mean lesion width of 14.4±2.6 mm for left PVs and 11.9±1.9 mm for right PVs. Complete PV encirclement of right PVs was observed in 76.7% of the patients, of left PVs in 76.7% and of both right and left PVs in 66.7% of the patients.

Conclusion
Pulmonary vein isolation implementing a very high-power short-duration protocol showed high feasibility in terms of short procedural duration and high acute efficacy with low complication rates. Cardiac MRI showed durable complete PV lesions in a high number of patients 3 months post ablation.
https://dgk.org/kongress_programme/ht2022/aPP272.html