Usefulness of Reversed U-Curve Technique to EnhanceMapping and Ablation Efficiency in the Treatment ofPulmonary Sinus Cusp-Derived Ventricular Arrhythmias.
Reversed U-curve and nonreversed U-curve (conventional technique) were both reported to be effective in treating pulmonary sinus cusp (PSC)-derived ventricular arrhythmia (VA). The aim of this study was to evaluate the characteristics between two methods. We enrolled 37 consecutive patients with PSC-derived VA who underwent radiofrequency catheter ablation using a contact force (CF)-sensing catheter. Reversed U-curve and conventional method were routinely used for each patient. For the 37 patients with PSC-VA (14 cases in left cusp [LC], 12 in right cusp, and 11 in anterior cusp), only 7 patients from the LC were ablated using conventional method whereas the others underwent successful reversed U-curve ablation. For the reversed U-curve mapping, presence of a near-field sharp potential and QS wave at the best mapping site were observed with a higher frequency; CF in 3 sinuses was always higher except for LC (p <0.001, p <0.001, and p = 0.18, respectively); the bipolar potential amplitude was significantly higher (1.52 ± 1.75 mV vs 1.02± 2.37 mV, p <0.001), and increased with CF (p <0.001). In conclusion, reversed U-curve technique allows for sufficient contact and better catheter stability, enhancing mapping and ablation efficiency in the treatment of PSC-derived VA, particularly for right and anterior sinuses.