Novel Predictor for New-Onset Atrial High-Rate Episode in Patients With a Dual-Chamber Pacemaker

Figures

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  Figure 1.. Study flowchart. Of 258 patients with newly implanted cardiac implantable electronic devices (CIEDs), 101 patients without a previous diagnosis of atrial fibrillation (AF) and with preceding sinus rhythm electrocardiograms (ECGs) were selected. In all patients, the appearance of a new-onset atrial high-rate episode (AHRE) was evaluated in the initial 1 year after CIED implantation. The 101 patients were then divided into 2 groups according to the presence or absence of AHREs. CRT, cardiac resynchronization therapy; ICD, implantable cardioverter defibrillator.

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  Figure 2.. Definition. P-wave analysis, including P-wave dispersion (PWD), was evaluated just prior to cardiac implantable electronic device (CIED) implantation. Atrial high-rate episodes (AHREs) were defined as any episodes of sustained atrial tachyarrhythmia of >170 beats/min and >5 min, with at least 1 episode detected occurring during the initial 1 year after CIED implantation.

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  Figure 3.. (A) Analysis of P-waves. P-wave duration was measured from the beginning of the P-wave deflection from the isoelectric line to the end of the deflection returning to the isoelectric line in all simultaneous 12 leads of the electrocardiogram (ECG). When a P-wave exhibited a biphasic form, the later negative phase was also included for the measurement of P-wave duration. The P-wave amplitude was measured as the height of the peak of positive deflection or the depth of the bottom of negative deflection from the isoelectric line of the onset point. In the case of a biphasic P-wave, the P-wave amplitude was measured as the difference between the positive peak and the negative bottom of the recording. (B) Representative examples of the analysis of P-wave dispersion (PWD). PWD was defined as the difference between the maximum and minimum P-wave durations as detected in the body surface 12-lead ECG. The maximum and minimum P-wave durations were calculated from the standard ECG during sinus rhythm. PWD was derived by subtracting the minimum P-wave duration from the maximum duration in any of the 12 ECG leads.

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  Figure 4.. Receiver operating characteristic (ROC) analysis for determining the cut-off value of P-wave dispersion (PWD). The best cut-off value of PWD in patients with cardiac implantable electronic devices and atrial high-rate episodes (AHREs) was determined to be 48 ms, with a sensitivity of 73.8% and a specificity of 77.9% (area under the curve [AUC] 0.90; P<0.0001). The arrows indicate the most powerful cut-off points for the appearance of new-onset AHRE.