Radiofrequency catheter ablation for improving myocardial work in patients with ventricular pre-excitation

Figures

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  Figure 1. Flowchart of participant selection. ECG, electrocardiogram; EPS, electrophysiological study; RFCA, radiofrequency catheter ablation.

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  Figure 2. A surface electrocardiogram of a patient with a left free-wall accessory pathway located at the 2 to 3 o’clock position of the mitral annulus at resting heart rate (A, D), heart rate of 100 bpm (B, E), and heart rate of 120 bpm (C, F). Images A-C and D-F were acquired before and after participants underwent RFCA, respectively. Before RFCA, as the heart rate increased, the delta wave widened (58 ms, 62 ms, and 64 ms at resting heart rate, heart rate of 100 bpm, and 120 bpm, respectively), and the QRS wave broadened (146 ms, 174 ms, and 184 ms at resting heart rate, heart rate of 100 bpm, and 120 bpm, respectively; A-C). After RFCA, the delta wave disappeared, and the QRS wave narrowed (80 ms, 82 ms, and 78 ms at resting heart rate, heart rate of 100 bpm, and 120 bpm, respectively) at each heart rate (D-F).

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  Figure 3. Graphs showing the changes at different heart rates in some electrocardiographic and echocardiographic indices of the 26 enrolled patients (pre-RFCA). As the heart rate increased, the delta wave (A) and QRS wave (B) widened, LVEF (C) and GLS (D) worsened, GWW (E) increased, and GWE (F) decreased. However, GWI (G) and GCW (H) did not show a discernible trend with increasing heart rate. RFCA, radiofrequency catheter ablation; LVEF, left ventricular ejection fraction; GLS, global longitudinal strain; GWW, global waste work; GWE, global work efficiency; GWI, global work index; GCW, global constructive work.

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  Figure 4. A bull’s-eye depicting regional and global myocardial work efficiency and LV pressure-strain loop (LVPSL) in a patient with a left free-wall accessory pathway located at the 2 to 3 o’clock position of the mitral annulus at resting heart rate (A,D), heart rate of 100 bpm (B,E), and heart rate of 120 bpm (C,F). Images in the upper line (A-C) and the ones in the lower line (D-F) were acquired before and after participants underwent RFCA, respectively. At each heart rate, global myocardial work efficiency (GWE) and LVPSL were significantly improved after participants underwent RFCA. LV, left ventricle; RFCA, radiofrequency catheter ablation; bpm, beats per minute.

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  Figure 5. A bull’s-eye depicting regional and global myocardial work efficiency and LV pressure-strain loop (LVPSL) in a patient with a septal accessory pathway at a resting heart rate (A,D), heart rate of 100 bpm (B,E), and heart rate of 120 bpm (C,F). Images in the upper line (A-C) and the ones in the lower line (D-F) were acquired before and after participants underwent RFCA, respectively. At each heart rate, global myocardial work efficiency (GWE) and LVPSL were significantly improved after participants underwent RFCA. LV, left ventricle; RFCA, radiofrequency catheter ablation; bpm, beats per minute.

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  Figure 6. A bull’s-eye depicting regional and global myocardial work efficiency and LV pressure-strain loop (LVPSL) in a patient with a right free-wall accessory pathway at a resting heart rate (A,D), heart rate of 100 bpm (B,E), and heart rate of 120 bpm (C,F). Images in the upper line (A,B,C) and the ones in the lower line (D,E,F) were acquired before and after participants underwent RFCA, respectively. At each heart rate, global myocardial work efficiency (GWE) and LVPSL were significantly improved after participants underwent RFCA. LV, left ventricle; RFCA, radiofrequency catheter ablation; bpm, beats per minute.