Real-time assessment of bidirectional block during pulmonary vein cryoablation

摘要

Real-time assessment of the occurrence of bidirectional block during balloon cryoablation is not routinely performed.We paced continuously inside the pulmonary vein (PV) at high amplitude (12 mA/1.0 ms) with the Achieve~R catheter (lasso7-8). These tracings illustrate the left superior PV before and during the beginning of balloon cryoablation. The left atrium (LA) was constantly captured (change in P-wave morphology-) at a rate slightly faster than the spontaneous sinus rhythm (preserved exit conduction). Observe that the first intracardiac electrograms clearly shows a sharp PV potential (e.g. lasso 2-3 and 7-8) in spontaneous sinus rhythm (preserved entrance conduction).