AB-452675-4 CORONARY ARTERIAL SPASM DURING CAVO-TRICUSPID ISTHMUS ABLATION WITH A NOVEL FOCAL PULSED FIELD ABLATION CATHETER: FINDINGS FROM CORONARY ANGIOGRAPHY AND FRACTIONAL FLOW RESERVE MEASUREMENTS

Pulsed field ablation (PFA) has been shown to avoid esophageal damage, PV stenosis and permanent phrenic nerve paralysis. But not studied in these trials was of the cavo-tricuspid isthmus (CTI), a uncommon adjunct target for during pulmonary vein isolation (PVI) procedures. Indeed, recent studies demonstrated that when PFA is performed adjacent coronary artery, there susceptibility vasospasm: study right artery (RCA) angiography universally severe RCA spasm, albeit subclinical. However, were with pentaspline catheter designed create broad electrical field, focal spot catheter. To evaluate potential cause spasm CTI ablation, but using As part clinical trial persistent AF (PersAFOne 3, NCT05272852), after PVI posterior wall 12F commercial (Farawave, BSC Inc.), an investigational 8F deflectable (Farapoint, Inc.). at 2kV (2 x 2.5 sec applications per site) fluoroscopy ICE guidance. Coronary FFR measurement (Abbott PressureWire X) before, each application site. Spasm categorized as mild (<50%), moderate (50-90%) or (>90%). At single center, 8 patients. Bidirectional conduction block achieved all patients mean 13.3 lesions/pt (range 8-18). One patient had left dominant arterial system, de minimis RCA; remaining, 6 7 developed (n=5) (n=1) determined by both (mean pressure differential 0.60, range 0.31-0.78 among developing spasm). There no EKG changes symptoms (albeit sedated patients). The time resolution 13.8 min. In additional patient, intracoronary NTG pretreatment (1 mg) administered before lesions delivered CTI: provoked. Focal provokes subclinical vasospasm RCA. Additional investigation necessary determine optimal dosing strategy prevent this phenomenon.