Mayur Lakhani1, Faisul Saiful1, Valay Parikh1, Nikhil Goyal1, Soad Bekheit1, Marcin Kowalski2. 1. Electrophysiology Department, Staten Island University Hospital, Staten Island, New York. 2. Electrophysiology Department, Staten Island University Hospital, Staten Island, New York. Electronic address: Marcin212@gmail.com.
Abstract
BACKGROUND: Cryoballoon ablation has been associated with a significant incidence of phrenic nerve injury (PNI). OBJECTIVE: The purpose of this study was to evaluate whether recordings of diaphragmatic compound motor action potentials (CMAP) on a modified lead I during cryoballoon ablation can predict PNI. METHODS: Cryoballoon ablation was performed in 109 patients with atrial fibrillation (AF). During ablation of the right-sided pulmonary veins, the phrenic nerve was paced from the superior vena cava. The right and left arm electrodes from a 12-lead ECG were positioned 5 cm above the xiphoid process and 16 cm along the right costal margin. The amplitude of CMAP was recorded on lead I during ablation. RESULTS: Cryoballoon was applied 424 times in 211 right-sided veins. PNI occurred in 7 (6.4%) patients. The average CMAP amplitude did not significantly change in patients without PNI from the initial average CMAP amplitude of 0.34 ± 0.18 mV to 0.32 ± 0.17 mV (P = .58). In patients who developed PNI, there was a significant decrease in the initial average CMAP amplitude during the ablation from 0.33 ± 0.14 mV to 0.09 ± 0.05 mV (P <.001). The maximal percent change in the average CMAP amplitude in patients with PNI was higher (70% ± 10%) than in patients without PNI (7.6% ± 7%; P <.001). In any patient without PNI, the CMAP amplitude did not decrease more than 35% from baseline. CONCLUSION: Recording of CMAP amplitude on a modified lead I is reliable and could be early and sensitive method for predicting PNI in patients undergoing cryoballoon ablation for AF.
BACKGROUND: Cryoballoon ablation has been associated with a significant incidence of phrenic nerve injury (PNI). OBJECTIVE: The purpose of this study was to evaluate whether recordings of diaphragmatic compound motor action potentials (CMAP) on a modified lead I during cryoballoon ablation can predict PNI. METHODS: Cryoballoon ablation was performed in 109 patients with atrial fibrillation (AF). During ablation of the right-sided pulmonary veins, the phrenic nerve was paced from the superior vena cava. The right and left arm electrodes from a 12-lead ECG were positioned 5 cm above the xiphoid process and 16 cm along the right costal margin. The amplitude of CMAP was recorded on lead I during ablation. RESULTS: Cryoballoon was applied 424 times in 211 right-sided veins. PNI occurred in 7 (6.4%) patients. The average CMAP amplitude did not significantly change in patients without PNI from the initial average CMAP amplitude of 0.34 ± 0.18 mV to 0.32 ± 0.17 mV (P = .58). In patients who developed PNI, there was a significant decrease in the initial average CMAP amplitude during the ablation from 0.33 ± 0.14 mV to 0.09 ± 0.05 mV (P <.001). The maximal percent change in the average CMAP amplitude in patients with PNI was higher (70% ± 10%) than in patients without PNI (7.6% ± 7%; P <.001). In any patient without PNI, the CMAP amplitude did not decrease more than 35% from baseline. CONCLUSION: Recording of CMAP amplitude on a modified lead I is reliable and could be early and sensitive method for predicting PNI in patients undergoing cryoballoon ablation for AF.
Authors: Mansour Razminia; Hany Demo; Carlos Arrieta-Garcia; Oliver J D'Silva; Theodore Wang; Richard F Kehoe Journal: J Atr Fibrillation Date: 2014-06-30