Song-yun Chu, Jing Zhou, Yan-sheng Ding. Puzzling pacing threshold in a patient with cardiac resynchronization therapy device[J]. World Journal of Emergency Medicine, 2022, 13(3): 237-238.
Pacing threshold testing during the procedure (A and B) and before the procedure (C). A and B: right ventricular and left ventricular pacing threshold test during the procedure; arrows indicated the loss of capture; C: “satisfactory” biventricular pacing before and after the replacement procedure.
Figure 1.
Figure 2.
Comparison of the EGM and ECG during the procedure and after the initial implantation. A and B: testing of pacing thresholds of right ventricle and left ventricle with DDD-mode and shortened AV delay; C: the pseudocaptured QRS configuration was identical to the intrinsic LBBB pattern before the CRT implantation; D and E: EGM and ECG immediately after CRT implantation; F: EGM of intrinsic beats; G: so-called biventricular pacing capture. EGM: electrogram; ECG: electrocardiogram; AV: atrioventricular; LBBB: left bundle branch block; CRT: cardiac resynchronization therapy.
Nobre Menezes M, de Sousa J, Marques P. Coronary vein pacing with standard active fixation leads for cardiac resynchronization. Europace. 2015; 17(10):1562.
doi: 10.1093/europace/euv207
pmid: 26142454
2
Vinther M, Risum N, Philbert BT. A large inherent delay between the ECG and EGM signals in the pacing system analyzer from Medtronic makes it unsuitable to estimate timing events during CRT implantation. J Electrocardiol. 2020; 58:33-6.
doi: 10.1016/j.jelectrocard.2019.11.001
), Yan-sheng Ding
