Potential feasibility of a novel over‐the‐wire microelectrode catheter for recording coronary sinus electrograms in patients with cardiac resynchronization therapy devices

Figures

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  FIGURE 1. The EPstar Fix AIV (Japan Lifeline) is a 2.7‐Fr over‐the‐wire type microcatheter with 10 electrodes, each measuring 0.65 mm in length and arranged at 5‐mm intervals. This device features an inner lumen that allows the insertion of a 0.014‐inch guidewire. The basic steps for using this microcatheter are as follows: (1) canulate the coronary sinus with a guiding catheter, (2) advance a 0.014‐inch guidewire to the intended target location, and (3) introduce the 2.7‐Fr microcatheter over the guidewire. The microcatheter can record the local electrograms without being affected by far‐field activation in bipolar mapping. Because it is possible to evaluate multiple consecutive bipolar electrograms simultaneously, this microcatheter can help us diagnose atrial tachycardias.

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  FIGURE 2. Fluoroscopic images obtained during the catheter insertion procedure. Instead of a 6‐Fr decapolare catheter with an inner lumen (EPstar Fixed CS; Japan Lifeline), a 5‐Fr multipurpose catheter is used as a guide for inserting the microcatheter to prevent any unexpected injury to the left ventricular lead. First, a 0.014‐inch guidewire and the EPstar Fix AIV are introduced into the 5‐Fr multipurpose catheter outside the body. The 5‐Fr multipurpose catheter is then advanced into the right atrium with the guidewire ahead of the device. Subsequently, the guidewire and EPstar Fix AIV are stored within the 5‐Fr multipurpose catheter, which is then navigated into the CS ostium using its curvature (A). A wire‐guided cannulation is an option in difficult cases. Next, the 0.014‐inch guidewire is advanced into the distal CS while ensuring that the tip of the guidewire is not repelled by venous stenosis or occlusion (B). Finally, the EPstar Fix AIV is advanced along the wire while an assistant holds it (C). When the microcatheter crosses the left ventricular lead, care should be taken not to dislodge the multipurpose catheter by counterforce and ensure that there is no resistance (D).