起搏器电池耗竭的心电图表现及临床意义

目的探讨起搏器电池耗竭的心电图表现及其临床意义。方法对23例临床证实起搏器电池耗竭患者的临床资料及心电图进行回顾性分析。结果起搏频率减慢或起搏频率不均6例;起搏频率奔放1例;感知功能异常6例;起搏功能异常3例;感知及起搏功能均异常4例;起搏方式改变3例。结论起搏器电池耗竭可以有多种心电图表现,但必须结合临床,要除外起搏器系统的机械故障及起搏器参数设置不当引起类似的心电图改变,对于证实起搏器电池耗竭的患者要及时更换起搏器。     

Interventricular septal mass in a patient with cardiac sarcoidosis

Sarcoidosis is a granulomatous disease that may involve multiple organ systems. The prognosis of sarcoidosis is influenced by the presence and severity of cardiac lesions. Thinning of the wall in the ventricular septum has often been reported, whereas an interventricular septal mass is rare. We describe a case of cardiac sarcoidosis resulting in a myocardial mass in the basal portion of the interventricular septum that was sensitive to corticosteroid treatment.     

Vasodepressor cough syncope masked by sleep apnea-induced asystole

Vasodepressor Cough Syncope. Cough syncope is classified among the neural-reflex "situational" faints, but whether the clinical consequences in affected individuals result from reflex triggered bradyarrhythmia or vasodepressor-induced hypotension, or both, is often unknown. In this report we describe findings in a patient with a clinical history consistent with cough syncope, and in whom documented multiple asystolic spells were at first believed to be responsible for symptoms. However, pacemaker therapy initiated at an outside facility failed to suppress symptoms, and subsequent referral for more detailed autonomic study revealed the asystole to be due to sleep apnea, whereas cough-induced vasodepressor hypotension was the basis of syncope in this individual; the latter provided a pathophysiologic target for prevention of recurring symptoms. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1024-1027, September 2012).     

Safety and Effectiveness of Transvenous Lead Extraction in Octogenarians

Transvenous Lead Extraction . Introduction: As the population ages, the number of elderly patients with implantable cardiac devices referred for transvenous lead extraction will dramatically increase in Western countries. The safety and effectiveness of lead extraction in elderly patients has not been well evaluated. We report the safety and effectiveness of transvenous lead extraction in octogenarians. Methods and Results: From January 2005 to January 2011, we reviewed data from consecutive patients ≥ 80 years referred to our institutions for transvenous lead extraction because of cardiac device infection or lead malfunction. Clinical characteristics, procedural features, and periprocedural major and minor complications were compared between octogenarians and younger patients. Out of 849 patients undergoing lead extraction in the participating institutions during the study period, 150 (18%) patients were octogenarians (mean age 84 years; range 80–96; 64% males). A significantly higher percentage of octogenarians presented with chronic renal failure (55% vs 26%; P < 0.001), history of malignancy (22% vs 6%; P < 0.001), and chronic obstructive pulmonary disease (46% vs 19%; P < 0.001). Complete lead extraction rates were similar in the 2 age groups (97% in octogenarians vs 96% in patients <80 years; P = 0.39). Periprocedural death occurred in 2 (1.3%) patients ≥80 years and in 5 (0.72%) patients <80 years (P = 0.45 for comparison). No differences in terms of other periprocedural major and minor complications were found between the 2 age groups. Conclusion: Despite presenting with a significantly higher rate of comorbidities, transvenous lead extraction can be performed safely and successfully in octogenarians. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1103‐1108, October 2012)     

Differential effects of ivabradine and ryanodine on pacemaker activity in canine sinus node and purkinje fibers

Effects of Ivabradine and Ryanodine on Cardiac Pacemakers . Introduction: It is generally accepted that at least 2 major mechanisms contribute to sinus node (SN) pacemaking: a membrane voltage (mainly I_f) clock and a calcium (Ca) clock (localized submembrane sarcoplasmic reticulum Ca²⁺ release during late diastolic depolarization). The aim of this study was to compare the contributions of each mechanism to pacemaker activity in SN and Purkinje fibers (PFs) exhibiting normal or abnormal automaticity. Methods and Results: Conventional microelectrodes were used to record action potentials in isolated spontaneously beating canine SN and free running PF in control and in the presence of 0.1 μM isoproterenol. Ryanodine (0.1–3 μM) and ivabradine (3 μM) were used to inhibit sarcoplasmic reticulum Ca²⁺ release or I_f, respectively. To induce automaticity at low membrane potentials, PFs were superfused with BaCl₂. In SN, ivabradine reduced the rate whereas ryanodine had no effect. Isoproterenol significantly accelerated automatic rate, which was decreased by ivabradine and ryanodine. In normally polarized PFs, ryanodine had no effects on the automatic rate in the absence or presence of isoproterenol, whereas ivabradine inhibited both control and isoproterenol‐accelerated automaticity. In PF depolarized with BaCl₂, ivabradine decreased BaCl₂‐induced automatic rate while ryanodine had no effect. Conclusion: In canine SN, I_f contributes to both basal automaticity and β‐adrenergic‐induced rate acceleration while the ryanodine‐inhibited Ca clock appears more involved in β‐adrenergic regulation of pacemaker rate. In PF, normal automaticity depends mainly on I_f. Inhibition of basal potassium conductance results in high automatic rates at depolarized membrane potentials with SN‐like responses to inhibition of membrane and Ca clocks. (J Cardiovasc Electrophysiol, Vol. 23, pp. 650–655, June 2012)     

Safety of repetitive nerve stimulation in patients with cardiac implantable electronic devices

Introduction: Pacemakers and implantable cardioverter-defibrillators (ICDs) are vulnerable to inappropriate sensing of electromagnetic interference (EMI), such as from nerve conduction studies. We conducted a prospective study to assess the safety of repetitive nerve stimulation (RNS). Methods: Fourteen patients undergoing insertion of 10 ICDs and 4 pacemakers under general anesthesia received RNS of the median, axillary, and spinal accessory nerves at 2 HZ and 50 HZ . We recorded detection of EMI and whether or not this resulted in an arrhythmia diagnosis or change in pacing output. Results: EMI was visible in 2 ICDs, without spurious tachyarrhythmia detection. EMI was observed in 3 of the 4 pacemakers, which led to pacing inhibition and a pause in 2, both of which were programmed to a unipolar sensing configuration. Conclusions: RNS is safe in patients with ICDs. In pacemaker patients, RNS appears safe during bipolar sensing, but caution is recommended in pacemaker patients with unipolar sensing. Muscle Nerve 47: 840–844, 2013     

自制双层盐袋固定袋应用于永久起搏器植入术后压迫的效果分析

摘要 目的：探讨自制双层盐袋固定袋在永久起搏器植入术后患者切口压迫中的效果。方法： 2015年1月～2016年6月间在心内科行永久起搏器植入术的患者,随机进行分组。对照组患者术后使用两个500g普通盐袋压迫12～24 h,观察组患者术后采用自制的双层盐袋固定袋压迫切口6～12 h。观察患者术后并发症、心理、睡眠状况、舒适度,患者和护士对压迫工具的满意度。结果：观察组与对照组相比,观察组患者术后并发症少、患者心理、睡眠状况及术后舒适度更好,患者和护士的满意度高（P＜0.05）。结论：使用自制的双层盐袋固定袋压迫切口处,临床使用效果满意,有效降低术后并发症,提高患者的睡眠质量。 关键词 盐袋;永久起搏器;切口压迫;并发症;舒适度     

Pacemaker infection secondary to burkholderia pseudomallei

Infection is a relatively rare but devastating complication of intracardiac device implantation. Burkholderia pseudomallei is the organism which causes melioidosis, an endemic and lethal infection in the tropics. We describe a case of pacemaker infection secondary to Burkholderia pseudomallei, which was treated by explantation of the device and appropriate antimicrobial therapy.     

Extraction of the inner coil of a pacemaker lead slid into the pulmonary artery

A patient required lead extraction for chronic draining sinus, due to abandoned leads. Preoperatively, the chest film showed a filament in the right pulmonary artery: it was the inner coil of an old atrial lead that, while remaining anchored to the auricle, slid outside the outer coil. By right subclavian approach, the old ventricular lead and the outer coil of the atrial lead were removed. Then, by right jugular approach, the freely floating end of the inner atrial coil was grasped by a pig-tail catheter, drawn back into the superior vena cava, exteriorized by a Lasso catheter, and finally extracted.