Prolonged PR interval and incidence of atrial fibrillation, heart failure admissions, and mortality in patients with implanted cardiac devices: A real-world survey

Abstract

Background: Prolongation of the PR interval has long been considered a benign condition, particularly in the setting of nonstructural heart disease.

Objective: The purpose of this study was to investigate the effect of PR interval on various well-adjudicated cardiovascular outcomes using a large real-world population data of patients with implanted dual-chamber permanent pacemakers or implantable cardioverter-defibrillators.

Methods: PR intervals were measured during remote transmissions in patients with implanted permanent pacemakers or implantable cardioverter-defibrillators. Study endpoints (time to the first occurrence of AF, heart failure hospitalization [HFH], or death) were obtained between January 2007 and June 2019 from the deidentified Optum de-identified Electronic Health Record dataset.

Results: A total of 25,752 patients (age 69.3 ± 13.9 years; 58% male) were evaluated. The average intrinsic PR interval was 185 ± 55 ms. In the subset of 16,730 patients with available long-term device diagnostic data, a total of 2555 (15.3%) individuals developed AF during 2.59 ± 2.18 years of follow-up. The incidence of AF was significantly higher (up to 30%) in patients with a longer PR interval (ie, PR interval ≥270 ms; P < .05). Time-to-event survival analysis and multivariable analysis showed that PR interval ≥190 ms was significantly associated with higher incidence of AF, HFH, or HFH or death when compared with shorter PR intervals (P < .05 for all 3 parameters).

Conclusion: In a large real-world population of patients with implanted devices, PR interval prolongation was significantly associated with increased incidence of AF, HFH, or death.

Keywords: Atrial fibrillation; Clinical outcomes; Heart failure; PR interval; Pacemaker.

Figure 1

Flow chart of patient selection. EHR = electronic health record; ICD = implantable cardioverter-defibrillator.

Figure 2

Unadjusted Kaplan-Meier estimates of freedom from atrial fibrillation (AF) among increasing quantiles of PR interval—both permanent pacemaker (PPM) and implantable cardioverter-defibrillator (ICD) in all patients (A), in patients with no history of pre-existing AF in both PPM and ICD (B), PPM only (C), and ICD only (D)—with quantile 1 (mean PR interval <150 ms; black line), quantile 2 (mean PR interval 150–170 ms; blue line), quantile 3 (mean PR interval 170–190 ms; purple line), quantile 4 (mean PR interval 190–220 ms; green line), and quantile 5 (mean PR interval ≥220 ms; orange line) shown over 5 years of follow-up. Log-rank test for comparison, P < .001.

Figure 3

Unadjusted Kaplan-Meier estimates of freedom from heart failure hospitalization among increasing quantiles of PR interval—both permanent pacemaker and implantable cardioverter-defibrillator (A), permanent pacemaker only (B), and implantable cardioverter-defibrillator only (C)—with quantile 1 (mean PR interval <150 ms; black line), quantile 2 (mean PR interval 150–170 ms; blue line), quantile 3 (mean PR interval 170–190 ms; purple line), quantile 4, (mean PR interval 190–220 ms; green line), and quantile 5 (mean PR interval ≥220 ms; orange line) shown over 5 years of follow-up. Log-rank test for comparison, P < .001. HFE = hospitalization for heart failure exacerbation.

Figure 4

Unadjusted Kaplan-Meier estimates of freedom from heart failure hospitalization or death among increasing quantiles of PR interval—both permanent pacemaker and implantable cardioverter-defibrillator (A), permanent pacemaker only (B), and implantable cardioverter-defibrillator only (C)—with quantile 1 (mean PR interval <150 ms; black line), quantile 2 (mean PR interval 150–170 ms; blue line), quantile 3 (mean PR interval 170–190 ms; purple line), quantile 4 (mean PR interval 190–220 ms; green line), and quantile 5 (mean PR interval ≥220 ms; orange line) shown over 5 years of follow-up. Log-rank test for comparison, P < .001. HFE = hospitalization for heart failure exacerbation.