Catheter entrapment in the Chiari network during catheter ablation

Figure 1. Electrograms recorded during the electrophysiology study: The PentaRay catheter (Biosense Webster, Inc, Diamond Bar, CA) has been entrapped near the inferior vena cava–right atrium RA junction. Note that atrial signals but no ventricular signals were recorded from the PentaRay catheter in this position. A premature ventricular contraction is shown. His = recording of His bundle potential; HRA = high right atrium; PENTARAY = signals from PentaRay catheter; RVA = right ventricular apex.

Figure 2. A: Tissue measuring 2 × 1 cm that was extracted with PentaRay catheter (Biosense Webster, Inc, Diamond Bar, CA). B: PentaRay catheter with no evident abnormalities. C: Microscopic examination of the tissue showing cardiac muscle fibers in short fascicles (long arrow) with a prominent intervening collagenous stroma (short arrow). Focally there is a reticulated architecture with overlying endocardial lining (arrowhead).

Figure 3. Transesophageal echocardiogram post-procedure. A: Four-chamber view, no evidence of pericardial effusion. B: Mid-esophageal right ventricular inflow 68 degrees showing a prominent Eustachian valve (arrow). IVC = inferior vena cava; LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.