摘要Objective To evaluate the PR to RR interval ratio (PR/RR,heart rote-adjusted PR) as a prognostic marker for long-term ventricular arrhythmias and cardiac death in patients with implantable cardiovener defibrillator (ICDs) and cardiac resynchronization therapy with defibrillators (CRT-D).Methods We retrospectively analyzed data from 428 patients who had an ICD/CRT-D equipped with home monitoring.Baseline PR and RR interval data prior to ICD/CRT-D implantation were collected from standard 12-lead electrocardiograph,and the PR/RR was calculated.The primary endpoint was appropriate ICD/CRT-D treatment of ventricular arrhythmias (VAs),and the secondary endpoint was cardiac death.Results During a mean follow-up period of 38.8 ± 10.6 months,197 patients (46％) experienced VAs,and 47 patients (11％) experienced cardiac death.The overall PR interval was 160 ± 40 ms,and the RR interval was 866 ± 124 ms.Based on the receiver operating characteristic curve,a cut-offvalue of 18.5％ for the PR/RR was identified to predict VAs.A PR/RR ≥ 18.5％ was associated with an increased risk of VAs [hazard ratio (HR) =2.243,95％ confidence interval (CI) =1.665-3.022,P ＜ 0.001) and cardiac death (HR =2.358,95％CI =1.240-4.483,P =0.009) in an unadjusted analysis.After adjustment in a multivariate Cox model,the relationship remained significant among PR/RR ≥ 18.5％,VAs (HR =2.230,95％CI =1.555-2.825,P ＜ 0.001) and cardiac death (HR =2.105,95％CI =1.101-4.025,P =0.024.Conclusions A PR/RR ≥ 18.5％ at baseline can serve as a predictor of future VAs and cardiac death in ICD/CRT-D recipients.