Performance of Implantable Defibrillator Pacing/Sensing Lead Adapters

The wide variety of implantable defibrillators (ICDs) available from different manufacturers and the lack of universal industry standards has resulted in the frequent need for lead adapters at time of ICD implant or change. We analyzed the performance of 81 consecutive ICD sensing/pacing lead adapters used between 1988 and 1993. A total of 66 adapters was used for new epicardial systems, and 15 adapters served as lead connectors during ICD generator replacement, Pacing/sensing lead adapters used were: model LA-201 (n = 28; 34.5%); model 030–308 (n = 26; 32%); model 5866–24 (n = 15; 18.5%); and miscellaneous (n = 12; 15%). After a mean follow-up of 21 ± 16 months, nine pacing/sensing lead adapters had documented or strongly suspected failure. Most often pacing/sensing lead adapters presented clinically as frequent aborted shocks. Actuarial probability of freedom from failure for model LA-201 was 83% at 1 year, and 72% at 2 and 3 years; this was poorer than for the other sensing leads combined (P = 0.01; hazard ratio = 4.92; 95% confidence intervals = 1.2–20; log-rank test). In conclusion, pacing/sensing lead adapters are a potential source of ICD system complications. Performance is dissimilar among different models; specifically, model LA-201 may not be safe in the long-term, and patients with this lead adapter need to be closely monitored.     

Remote detection of incessant slow VT with an ICD capable of home monitoring.

In this case report, we present a 57-year-old patient who suffered from incessant slow ventricular tachycardia because of a change in therapy 2 weeks after the implantation of an implantable cardioverter defibrillator (ICD) with Home Monitoring (HM). HM is a fully automatic and wireless system capable of transmitting device data including episode counters. The patient had mild symptoms with only short episodes of dizziness and would not have contacted the primary care centre. Due to HM, the arrhythmia was detected before the next routine follow-up, and the patient was seen the next day. HM made it possible to adjust the dosage of the newly established beta-blocker treatment in an outpatient setting and avoid hospitalization. HM yields the potential for remote detection of arrhythmias in ICD recipients, allowing alterations in device programming or medication.     

Quality-of-Life in Patients Receiving Implantable Cardioverter Defibrillators At or Before Age 40

As the use of ICDs increases, more young patients will be eligible to receive these devices. Such patients may have different concerns than older patients who more commonly receive ICDs. We investigated quality-of-life issues in patients followed by the Yale electrophysiology service who were ≤ 40 years old (mean = 28) at the time of ICD implant. Mean time since ICD placement was 3.3 years. Each patient received a modified SF-36 health questionnaire; 16 (88%) of 18 responded. Nine were women; ten were married. The highest education level attained was high school for 6 (37%), and college or beyond for 10 (63%). Ten patients were employed; eight held the same job before and after ICD placement. Four women conceived after ICD implantation; one experienced ICD discharge during pregnancy. All delivered healthy infants. AH patients felt their health was good to excellent, with 6 (38%) reporting an improvement in health since ICD placement. All felt capable of performing the activities of daily living, while 68% engaged freely in moderate physical activities. All patients felt they were average to very attractive. However, 63 % worried about how their clothes fit with the ICD. Three quarters of the patients felt the ICD interfered with social interactions, while 50% were concerned about sexual encounters. Thus, even though these young patients have body image concerns and may limit their activities to some degree, they are productive, active members of society who have benefitted from ICD placement.     

Sodium lauiyl sulphate damaged skin in vivo in man: a water barrier repair model

Background/aims: Few studies describe enhancing the repair of surfactant-induced damaged skin. In vivo human studies were conducted to evaluate the efficacy of a topical agent after sodium lauryl sulphate (SLS) induced water barrier disruption. Methods: Occlusive chambers with 1 % SLS were applied to the upper-backs of volunteers for 24 h, removed and topical agents applied on the SLS-treated skin sites daily for 5 days. Water barrier restoration was monitored by measuring transepidermal water loss (TEWL). Results: The data were expressed as the percentage of recovery representing normalization of water barrier function. Results showed that a topical agent produced more rapid improvement in barrier function than its placebo vehicle, markedly accelerating repair at 48 h (P<0.01), and persisting throughout the experiment (P<0.05), in comparison with SLS-control sites. Conclusions: This study suggests that topical agents may accelerate the repair rates of water barrier function in SLS-treated human skin. This model appears facile and robust for evaluating such repair.     

ICD-1O在病案管理信息系统中的转换过程

1转换编码(以下称转码)的意义及作用 转换编码是保持病案信息资料的连续性.病案信息连续性既便于与国际间进行交流,也有利于医院经营.认识到信息资料的连续在病案管理工作中、在整个医院管理工作中的重要性,我们决定不购买现成的ICD-10软件,而是开始寻找能将ICD-9转换到ICD-10的软件公司,其最终目的不仅是为了能使数据连续,保证原有信息准确,且要能达到长期维护<病案管理信息系统>,并能使软件不断更新和升级,以适应新的形势、新的要求和新的目的,最后同某软件公司达成一致协议.     

第四代埋藏式自动复律除颤器的临床应用

2例冠心病,陈旧心肌梗塞并持续室性心动过速的病人,服用2～3种抗心律失常药无效而考虑埋藏式自动复律除颤器(ICD)治疗.术前电生理检查均诱发了持续室速,并了解了诱发和终止条件.经锁骨下静脉穿刺安装了第四代ICD.术后随访7～12个月中,2例均有室速发作而正确放电,但1例有窦性心动过速被误感知现象,经程序调整而消失.本文强调了适应症选择,术前电生理检查和术后随访的重要性.     

Predicting imminent episodes of ventricular tachyarrhythmia using heart rate

BACKGROUND: A reliable predictor of an imminent episode of ventricular tachyarrhythmia that could be incorporated in an implantable defibrillator capable of preventive therapy would have important clinical utility. METHOD: A test set of 208 R-R records saved by defibrillators spanning a mean of 1.6 hours before sustained tachyarrhythmia were used to derive criteria that would improve the specificity of the previously identified monotonic heart rate acceleration predictor. Additional criteria were used, namely two such patterns need to occur within a period of 1.8 hour and the heart rate during these accelerations exceeds 86 bpm (700 ms). The specificity was tested using R-R records matched in duration from 26 control patients with defibrillators during normal periods. RESULTS: The basic acceleration pattern was found during sinus rhythm in the 1.8-hour period prior to 83% of episodes of ventricular tachyarrhythmia. It was also found in 43% of the matched set of non-arrhythmic records, corresponding to a specificity of 57%. With the two extra requirement of multiplicity within 1.8 hour and peak heart rate, the sensitivity of the proposed predictor is reduced to 53%, but the specificity is increased to 91%, which corresponds to an average false positive rate of 0.8 event/day across the patient population. CONCLUSION: A ventricular tachyarrhythmia predictor based on a pattern of heart rate acceleration has been proposed that can yield sensitivity from 53% to 69%, with specificity up to 91%. Instances of this predictor increase significantly prior to an episode of tachyarrhythmia.     

Prevalence and characterization of asymptomatic pacemaker and ICD lead perforation on CT

BACKGROUND: Pacemakers and implantable cardiac defibrillators (ICDs) are widely used for the management of cardiac arrhythmias and congestive heart failure (CHF). Acute implantation complication rates range from 3% to 7%. The aim of this study is to describe the incidence of lead perforation on computed tomography (CT), and correlate these findings with electrophysiologic data. METHODS: Images of 100 consecutive patients with permanent pacemakers (n = 72) or ICDs (n = 28) who underwent multidetector CTs of the chest were identified. Cases were reviewed by 2 cardiothoracic radiologists, and a third if there was disagreement. Each CT was reviewed for device and fixation type, tip position, and presence of pericardial effusion. Results were correlated with lead impedance and pacing threshold, when available [79% (79/100)]. A cardiac electrophysiologist interpreted device data. RESULTS: All 100 patients had right ventricular leads (58 passive, 42 active) and 61 had right atrial leads (12 passive, 49 active). 15% (15/100) of patients had a lead perforation. Perforation rates were 15% (9/61) for atrial and 6% (6/100) for ventricular leads (P < 0.05, chi square). Four of 28 (14%) right ventricular ICD leads and 2 of 72 (3%)right ventricular pacemaker leads were perforated (P < 0.05, chi square). 12% (6/49) of active right atrial leads, and 25% (3/12) of passive right atrial leads perforated (P = NS, chi square). 7% (3/42) of active right ventricular leads, and 5% (3/58) of passive ventricular leads perforated (P = NS, chi square). Electrophysiologic parameters did not differ significantly between perforated and nonperforated leads. CONCLUSION: Asymptomatic perforation is a common phenomenon and rarely resulting in electrophysiologic consequences. Atrial leads perforated more frequently than ventricular leads, and ventricular ICD leads perforated more frequently than ventricular pacemaker leads.     

Incidence and significance of far-field R wave sensing in a VDD-implantable cardioverter defibrillator

BACKGROUND: A VDD-implantable cardioverter-defibrillator (ICD) provides atrioventricular (AV) synchronous stimulation when necessary and incorporates the advantages of dual chamber arrhythmia discrimination algorithms both at potentially lower costs and less periprocedural complications than a DDD-ICD system. A prerequisite for correct dual chamber ICD function is reliable atrial sensing. METHODS: We evaluated atrial near- and ventricular far-field sensing and its impact on the dual-chamber detection algorithm in 106 patients with a single-lead VDD-ICD during a 12-month follow-up period. RESULTS: Six hundred and thirty-nine follow-ups were included. Mean near-field amplitude was 3.82 +/- 1.76 mV; mean far-field amplitude was 0.31 +/- 0.15 mV. 46% of patients had far-fields >0.35 mV and 35% of patients showed atrial EGM markers corresponding to a ventricular far-field in at least one follow-up. Six hundred and forty-five tachycardia episodes were evaluated. Due to far-field sensing, three of 66 episodes (4.5%) of sinus tachycardia were misclassified as ventricular tachycardia (VT), leading to antitachycardia therapies. Delayed detection of VT was seen in a 12 of 323 episodes (3.7%) in five of 62 patients (8%) having VT events (delay 6.4 +/- 6.0 seconds (range 2-24 seconds)). Stable far-field amplitudes <0.2 mV in a follow-up had a high negative predictive value for the occurrence of malfunction during tachycardia-conversely, high far-field amplitudes or a high incidence of far-field markers are only moderately correlated with malfunction. CONCLUSIONS: Ventricular far-field sensing in a VDD-ICD is not uncommon, however, tachycardia detection by the dual chamber algorithm is not seriously impaired by far-field sensing.     

Impact of rotavirus vaccination on the burden of acute gastroenteritis in Nagoya city,Japan

BackgroundIn Nagoya city, Japan, rotavirus (RV) vaccination has been available since 2011 with estimated coverage reaching 92% by 2015 after the introduction of a public subsidy in 2012. This study assessed the impact of vaccination on the RV gastroenteritis (RVGE) burden in children aged <5 years old (y) by comparing RVGE hospitalizations and outpatient visits during pre-vaccination (2007–2011), transition (2011–2012) and subsidization (2012–2016) periods.MethodsAll hospitalizations and outpatient visits in children aged <5 y from 2 administrative districts of Nagoya city were identified from the hospital-based electronic databases of 4 hospitals. RVGE cases were identified by diagnostic code and/or positive results of diagnostic kits.ResultsCompared to the pre-vaccination period, there was a decrease in RVGE hospitalizations for children <5 y from 5.59 per 1000 person-year (kPY) to 3.65/kPY in the subsidization period (i.e. 34.69%). In children <1 y, the incidence of RVGE hospitalizations decreased continuously from 6.62/kPY in the pre-vaccination period to 1.84/kPY in the subsidization period (i.e. 72.19%). The highest decrease was observed in the subsidization season i.e. when high coverage was reached: 69% and 75.57% in the 2013/2014 season for 2–3 y and 3–4 y, and 74.03% in the 2014/2015 season for 4–5 y, respectively. Proportion of RVGE outpatient visits decreased by 87.44% for children <1 y and 57.05% for <5 y from the pre-vaccination to the subsidization period. This decrease started the first year of subsidization for children <1 y, 1–2 y and 2–3 y (78.89%, 18.86% and 5.80%) and the second year (2013/2014 season) for children 3–4 y and 4–5 y (87.73% and 51.78%).ConclusionsAlthough yearly fluctuations have been observed, the introduction of vaccination significantly decreased pediatric RVGE hospitalizations and outpatient visits, especially in the age group eligible for vaccination. During the second and third year of subsidization, we observed a herd protection effect on other age groups <5 y who were not eligible for vaccination.Clinicaltrial.gov.registered#:NCT01733862.