Korean Circulation Journal 대한심장학회지 순환기 Joung B, et al. Korean Circ J. 2018 Dec;48(12):1033-1080. https://doi.org/10.4070/kcj.2018.0339

Objectives The predictors of pacing-induced cardiomyopathy (PICM) for complete atrioventricular block (CAVB) have not yet been defined. The aim of this study was to investigate the major determinant of the occurrence of PICM. Setting This is a multicentre, retrospective analysis of CAVB from tertiary referral centres in Daejeon, South Korea. Participants A cohort of 900 consecutive patients with an implanted pacemaker was collected from December 2001 to August 2015. Of these, a total of 130 patients with CAVB with pacing-dependent rhythm who underwent ECG and echocardiogram before and after implantation were analysed for the occurrence of PICM. Outcome measures Cox proportional hazards models evaluated the determinant of PICM by ECG, device parameters and echocardiogram over a mean of 4.5 years. Results PICM was observed in 16.1% (n=21) of all patients with CAVB (age, 64±11 years; male, 36.2%). The preimplant left ventricular (LV) ejection fraction (66%±9% vs 66%±8%) and non-apical pacing (40.4% vs 33.3%) were similar; however, the native QRS duration (124±34 ms vs 149±32 ms) and the paced QRS duration (pQRSd) (139±29 ms vs 167±28 ms) were significantly different between the two groups. The postimplant LV ejection fraction (61%±7% vs 31%±8%) was also significantly different at the end of follow-up. A pQRSd significantly correlated with PICM (HR 1.05, 95% CI 1.02 to 1.09, P=0.001). A pQRSd with a cut-off value of above 140 ms had a sensitivity of 95% while a pQRSd with a cut-off value of above 167 ms had a specificity of 90% for PICM. Conclusion In patients with CAVB with pacing-dependent rhythm, regardless of the pacing site, the pQRSd is a major determinant of the occurrence of PICM.

Lee SR, et al. Yonsei Med J. 2019 Mar;60(3):277-284. https://doi.org/10.3349/ymj.2019.60.3.277

Korean Circulation Journal 대한심장학회지 순환기 Kim H, et al. Korean Circ J. 2017 Nov;47(6):877-887. https://doi.org/10.4070/kcj.2017.0146

Lee JM, et al. Korean Circ J. 2016 Sep;48:e51. https://doi.org/10.4070/kcj.2017.0389

Aims This study aimed to elucidate the risk for stroke and systemic embolism (SE) in patients with atrial fibrillation and heart failure (HF) according to HF type. Methods and results A total of 10 780 patients with atrial fibrillation were enrolled in a multicentre prospective registry and divided according to HF type: no‐HF, HF with preserved ejection fraction (EF) (HFpEF), HF with mid‐range EF (HFmrEF), and HF with reduced EF (HFrEF). Each group included 237 age‐matched and sex‐matched patients (age, 69.0 ± 10.3 years; men, 69.6%). The baseline characteristics, cumulative incidence, and hazard ratios for stroke/SE and major bleeding were compared across the groups. Patients with HF accounted for 10.3% of the total population; HFpEF, HFmrEF, and HFrEF represented 43.7%, 23.6%, and 32.7% of the patients with HF, respectively. The CHA₂DS₂‐VASc score was significantly higher in the HFpEF, HFmrEF, and HFrEF groups than in the no‐HF group. The annual stroke/SE incidence rates were 2.8%, 0.7%, 1.1%, and 0.9% in the HFpEF, HFmrEF, HFrEF, and no‐HF groups, respectively. The cumulative incidence of stroke/SE was significantly highest in the HFpEF group at 22.8 ± 10.0 months (P = 0.020). The stroke/SE risk was higher in the HFpEF group than in the HFmrEF and HFrEF groups (hazard ratio, 3.192; 95% confidence interval, 1.039–9.810; P = 0.043). E/e' value was an independent risk factor for stroke/SE. There were no significant differences in the incidence of major bleeding across the groups. Conclusions The stroke/SE risk was the highest in the HFpEF group and comparable between the HFmrEF and HFrEF groups.