A 41-year-old man underwent pulmonary vein isolation using the second-generation cryoballoon. Following selective angiography (Panel A), right pericardiophrenic vein was cannulated with a 3Fr octapolar electrode catheter over a guidewire (0.014 in.) (Panel B). The threshold of obtaining the maximal compound motor action potential (CMAP) amplitude was 3.0 V with 2.0 ms pulse width. The variability of the amplitude during the cryoapplications was <10%. The major limitation of diaphragmatic CMAP monitoring to anticipate right phrenic nerve injury includes the variability (<30%) in the amplitude during the procedure. Pericardiophrenic vein might be an excellent pacing site to obtain highly stable CMAP during the procedure.
Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: [email protected].
