Placement of catheters without magnetic sensors in the coronary sinus without fluoroscopic guidance: Feasibility and safety evaluation

BACKGROUND: A three‐dimensional (3D) mapping system is essential to reduce radiation exposure during catheter ablation. When using the CARTO 3D mapping system, only the catheter with magnetic sensor can visualize its location. However, once target chamber matrix is created using the catheter, even the catheters without magnetic sensors (CWMS) can enable visualization. We aimed to investigate the feasibility and safety of placing a CWMS in the coronary sinus (CS) without fluoroscopic guidance. METHODS: The study group comprised 88 consecutive patients who underwent catheter ablation. CWMS placement was performed without fluoroscopic guidance in 47 patients and with fluoroscopic guidance in 41 patients. Placement without fluoroscopic guidance was performed after creating a visualization matrix of the CS, right atrium, and superior vena cava using a catheter with a magnetic sensor. Feasibility and safety were compared between the two groups. RESULTS: Successful catheter placement was achieved in all patients without fluoroscopic guidance, with no inter‐group difference in the median procedure time: with guidance, 120.0 [96.0–135.0] min, and without guidance, 110.0 [97.5–125.0] min; p = .22. However, radiation exposure was significantly shorter, and the effective dose was lower without fluoroscopic guidance (0 [0–17.5] s and 0 [0–0.004] mSv, respectively) than with fluoroscopic guidance (420.0 [270.0–644.0] s and 0.73 mSv [0.36–1.26], respectively); both p < .001. CONCLUSIONS: CWMS placement without fluoroscopic guidance is feasible, safe to perform, and does not involve complications. Our technique provides an option to decrease radiation exposure during catheter ablation and electrophysiological testing.