Standard group
PNP
PHRENIC NERVE PARALYSIS, LEAKAGE
The achieve electrode was sent into the target PV for recording the PV potential, the CB was inflated in the left atrium, the filled CB was pushed along the Achieve electrode to the target PV orifice for occlusion, and the contrast medium was injected into the hollow lumen of the CB catheter, and then observed under fluoroscopy. If there is no contrast medium leakage into the left atrium, the balloon is considered to be well-occluded. PST is used to retreat the CB properly, observe the slight leakage of the contrast medium, and determine that the CB is located in the vestibule of the PV. When the second-generation balloon is used for freezing, the freezing time is 180 s, one freezing/thawing cycle at a time. If the balloon temperature is lower than − 55 °C, the freezing will be terminated immediately. After each freezing, achieve electrode was used to evaluate the electrical isolation of PV. CB ablation is usually performed in the order of left superior pulmonary vein (LSPV), left inferior pulmonary vein (LIPV), right superior pulmonary vein (RSPV), and right inferior pulmonary vein (RIPV). To prevent phrenic nerve paralysis (PNP), during CB ablation of the right pulmonary vein, the 4-pole electrode was sent to the superior vena cava to continuously pace the phrenic nerve. The assistant placed the hand on the patient's abdomen or observed the diaphragm movement under fluoroscopy. If it is found that the diaphragm movement weakens or disappears, it is necessary to stop freezing immediately. The endpoint of the operation was the electrical isolation of all PVs. If the electrical isolation of PV cannot be achieved after freezing 3–4 times, a radiofrequency (RF) ablation catheter should be used for supplementary ablation.