Intracardiac Echocardiography to Guide the Ablation of Parahisian Arrhythmias.

Arrhythmias from the perinodal region have been described for accessory pathways (APs), atrial tachycardias (AT), premature ventricular complexes (PVCs), and ventricular tachycardia (VT). The parahisian (PH) region encompasses anatomic structures that include the atrioventricular (AV) node and His-Bundle (HB). These locations are at high-risk for inducing AV block during catheter ablation in the electrophysiology laboratory. PH arrhythmias were initially defined as having sites of origin within 10 mm of the largest HB potential (>0.1 mV) recording site, but more recent definitions have included any site that has an HB potential at the ablation site. Intracardiac echocardiography (ICE) use offers real-time visualization of the catheter tip-to-tissue contact and can monitor for acute complications during atrial and ventricular procedures. ICE also enables a broad appreciation of real-time cardiac structures, which is invaluable in navigating the complex anatomy of the PH region.