Left Ventricular Transvenous Electrode Dislodgement After Mustard Repair for Transposition of the Great Arteries

An 11-year-old girl who underwent Mustard's operation for complete transposition of the great arteries in infancy, developed Mobitz type II second-degree AV block 81/2 years later. A transvenous, active fixation left ventricular lead was inserted and connected to a rate responsive pacemaker. Two years later the lead dislodged due to the child's growth. A new active fixation electrode was positioned in the left ventricle below the pulmonary valve, leaving an electrode loop in the ventricle. Such an approach may prevent lead dislodgement due to growth after intraatrial repair for transposition of the great arteries, but regular radiological or echocardiographic follow-up of lead position is recommended in these patients.     

Effect of scanner in longitudinal diffusion tensor imaging studies

The purpose of this study was to evaluate the effects of longitudinal drift in scanner hardware, inter-scanner variability (bias), and scanner upgrade on longitudinal changes in global and regional diffusion properties using longitudinal data obtained on two scanners of the exact same model at one institution. A total of 224 normal subjects were scanned twice, at an interval of about 1 year, using two 3.0-T scanners of the exact same model. Both scanners were simultaneously upgraded during the study period. The subjects were divided into four groups according to the combination of scanners used. With use of tract-based spatial statistics, we evaluated the effects of scanner drift and inter-scanner variability (bias) on global and regional fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) changes of the white matter. Even with scanners of the exact same model, inter-scanner variability (bias) significantly affected longitudinal results. FA, AD, and RD of the white matter were relatively stable within the same scanner. We also investigated the effect of scanner upgrade on longitudinal FA, AD, and RD changes. The scanner upgrade included only software upgrade, not hardware upgrade; however, there was a significant effect of scanner upgrade on longitudinal results. These results indicate that inter-scanner variability and scanner upgrade can significantly affect the results of longitudinal diffusion tensor imaging studies.     

Automatic Implantable Cardioverter Defibrillator/Permanent Pacemaker Interaction: Loss of Pacemaker Capture Following AICD Discharge

A 78-year-old man treated with amiodarone for recurrent ventricular tachycardia, had sequential placement of a bipolar VVI pacemaker and an automatic implantable cardioverter defibrillator (AICD). During defibrillation threshold testing, there was failure to capture of the pacer in the post-shock period. The time of failure to capture appeared energy-related: the greater the energy delivered, the longer the failure to capture. Careful attention will be necessary in constructing combined AICD/pacemaker units.     

Permanent Pacemaker Implantation in a Pregnant Woman with the Guidance of ECG and Two-Dimensional Echocardiography

A 30-year-old pregnant woman was admitted to the Cardiology Research Center with syncope, dizziness, and fatigue on exertion. On ECG complete atrioventricular block was diagnosed. Permanent pacemaker implantation was performed with the guidance of ECG and two-dimensional echocardiography and without the use of fluoroscopy.     

Extension of Life-Table Methodology to Allow for Left-Censoring in Survival Studies of Pacing Devices Followed by Commercial Monitoring Services

The actuarial life-table is commonly used to describe lifetime data of living subjects and manufactured products. The life-table method allows subjects to come under observation at different times and, thus, to have differing lengths of follow-up, by assuming all subjects begin their lifetimes relative to the outcome of interest at some common point in time. As time progresses, subjects are withdrawn from the life-table when their period of observation has elapsed. This pattern of follow-up is often termed "right-censoring." An important feature of the classical life table approach is that the time at which the subject is placed at risk is known, and the status relative to the outcome of interest is known for the entire time at risk. Sometimes, however, subjects cannot be observed for some period after the beginning of their lifetimes. The example to be considered involves follow-up data collected by a commercial pacemaker monitoring service, to which patients subscribe, generally at some point following the actual implant of the pacemaker. Since the outcome of interest is device failure after implant, some means of dealing with the lack of information between implant and initiation of follow-up is needed. The extension of the actuarial life-table to accommodate this "left-censoring" will be described in this paper.     

Orthodromic Pacemaker Circus Movement Tachycardia

We report on the case of a 33-year-old woman with sick sinus syndrome who had an orthodromic pacemaker circus movement tachycardia (PCMT), with antegrade atrioventricular (AV) conduction and a retrograde pathway by means of a DDD (AV universal) pacemaker. This PCMT was provoked and sustained by premature ventricular contraction-synchronous atrial stimulation (PVC-SAS), which is a new feature for the prevention of anti-dromic PCMTs. The conditions for occurrence of this tachycardia were: (1) PVC-SAS; (2) atrial undersensing; (3) first degree AV block. Recommendations for prevention of this pacemaker-mediated tachycardia are given.     

Pacemaker leads

Present day pacemaker leads are far superior in every respect to those of the past. Modification of fixation characteristics has reduced displacement rates to 1% or less in most centers. Fracture of multifilar leads is a rarity. Biodegradation of polyurethane insulation appears to be an isolated problem specific to individual lead models and may be related to physical stresses incurred during manufacture or lead insertion. Recent evidence has incriminated an interaction of polyurethane with silver which arises from the drawn braised strand conductor substrate of those leads in which this problem has been noted. This may explain why the problem has been restricted to specific lead models of one manufacturer to date. Lack of uniformity of lead terminal size between manufacturers and even within the same manufacturer's product line continues to baffle this observer. Although past problems of lead displacement have been markedly reduced, the difficulty of removing chronic leads which have become septic appears to have worsened. Modification of existing leads to ensure that the interface between electrode tip and proximal shaft is unidiametric is essential.     

Clinical Impact of Oral Anticoagulation in Patients with Atrial High-rate Episodes

Background: Atrial high-rate episodes (AHREs) are common in pacemaker patients. Our aims were to compare patients with AHREs to those without them and to assess if, in those with AHREs, the initiation of oral anticoagulation (OAC) has any clinical impact on the occurrence of ischemic and hemorrhagic events. Methods: From 2014-2017 we selected patients with pacemaker in whom AHREs were detected. AHREs were defined as episodes lasting more than 6 minutes if the electrogram was available or more than 6 hours if not. We used an age- and gender-matched population with pacemaker but no AHRE as a control group (observational study). Those with AHRE were referred to their assistant physician to decide OAC initiation, based on individual circumstances (interventional study). In interventional study, the primary outcome was a composite of systemic thromboembolism or major bleeding. Secondary outcomes were clinical relevant nonmajor bleeding, major and nonmajor bleeding, CV death, and death from all causes. Results: AHREs were detected in 86 patients: 69 patients initiated OAC and the remaining 17 patients did not. When comparing patients with and without AHRE, baseline characteristics were not different between the groups, except for indexed left atrium volume—40 mL (IQR: 34-50) in AHRE group versus 35 mL (IQR: 34-40) in control group (P?=?.014). AHREs were associated with future development of atrial fibrillation (AF) and the risk was higher if AHRE duration was superior to 6 hours. Death and cardiovascular (CV) death were not significantly different between the groups with and without AHRE. Primary outcome occurred in 4.9 per 100 person-year in OAC group versus 3.4 per 100 person-year in non-OAC group (HR 1.4, 95% CI .2-11.3, P?=?.78). Secondary outcomes were not significantly different in the groups. Conclusions: In this group of patients with pacemakers, the presence of AHREs was useful for predicting the future development of AF and the risk of AF was higher in those with a longer duration of AHRE. In the AHRE group, OAC therapy was not associated with a significant difference in the risk of thromboembolism or major bleeding.     

前列腺癌根治术后Gleason评分升级的影响因素分析（基于2014版ISUP分组）

目的 在2014版ISUP分组的基础上,探讨前列腺癌根治术后Gleason升级的影响因素。方法 回顾性收集2016~2021年于新疆医科大学第一附属医院行前列腺癌根治术的临床数据189例,根据前列腺癌根治术后Gleason是否较前列腺穿刺时升高,分为Gleason升级组（GGU组）60例及Gleason非升级组（非GGU组）129例。单因素分析及多因素Logistic回归对比两组资料的差异。结果 单因素分析中穿刺肿瘤组织长度、Gleason主要区域评分及Gleason次要区域评分与GGU有关（P<0.05）,多因素Logistic回归后,高血压病史（OR=2.651）、Gleason主要区域评分（OR=4.186）、穿刺肿瘤组织长度（OR=10.989）及穿刺阳性率（OR=3.684）与GGU有关（P<0.05）。结论 高血压病史、穿刺标本Gleason主要区域评分、标本中肿瘤组织长度及穿刺阳性率可能与GGU的风险相关。     

The influence of native aortic valve calcium and transcatheter valve oversize on the need for pacemaker implantation after transcatheter aortic valve insertion

Objective

Native aortic valve calcium and transcatheter aortic valve oversize have been reported to predict pacemaker implantation after transcatheter aortic valve insertion. We reviewed our experience to better understand the association.