Paced QRS duration during right ventricular pacing using a pseudo-surface electrocardiogram recorded by a pacemaker programmer
T Mine, R Iwai, M Sugitani, S Terao, Y Sumiyama, M IshiharaAbstract
Background
Prolongation of paced QRS (p-QRS) duration (>163ms) during right ventricular pacing has been reported as a predictor of pacing-induced cardiomyopathy (PICM). Meanwhile, the electrocardiogram detected by the pacemaker device possibly mimics a surface electrocardiogram and may be an alternative to a 12-lead electrocardiogram for measuring p-QRS duration.
Purpose
To evaluate the correlation of paced QRS duration during right ventricular pacing between pseudo-surface electrocardiogram and standard 12-lead electrocardiogram.
Methods
We retrospectively studied 63 right ventricular pacing-dependent patients with pacemaker implantation (age 82±9years, 31 men, 15 with sick sinus syndrome, 39 with atrioventricular block, and 9 with atrial fibrillation bradycardia). We defined the far-field electrogram (EGM) between the Can and the RV ring electrode recorded in the pacemaker as a pseudo-surface electrocardiogram. The time from the QRS start point to the end point, at which the waveform returns to the baseline, was defined as the QRS width during RV pacing (EGM p-QRS duration). The p-QRS duration automatically measured on the 12-lead electrocardiogram (ECG p-QRS duration) was compared with that measured on the electrogram (EGM p-QRS duration). The reproducibility of EGM p-QRS duration measurements between two examiners was evaluated.
Results
EGM p-QRS duration (Figure 1) detected by pseudo-surface electrocardiogram was 104±15ms, ECG p-QRS duration showed 158±20ms. EGM p-QRS duration was positively correlated with ECG p-QRS duration（r²＝0.53, p＜0.001). The ECG p-QRS duration of 163ms corresponded to an EGM p-QRS duration of 110ms (Figure 2). Reproducibility of EGM p-QRS duration was high (r²=0.7, p<0.001), and the upper and lower limits of mean differences for EGM p-QRS duration were less than two standard deviations.
Conclusion
The EGM p-QRS duration correlated well with the ECG p-QRS duration, suggesting that it may be a predictor of PICM. However, its predictive value needs to be reevaluated.