No gender differences in pacemaker selection in patients undergoing their first implantation

Recent studies have indicated that women were less likely to receive sophisticated pacemaker devices than men. These differences could not be fully explained by demographic and clinical variables. The purpose of the present study was to assess whether a gender related difference might exist in pacemaker mode selection in patients undergoing their first implantation in The Netherlands. Records of first implants (n = 39,217) collected from 1988 through 1997 covering 95% of all implantations in The Netherlands. From this population 33,564 (85.6%) patients were included for final analysis. We observed no significant sex differences in pacemaker selection in patients with atrioventricular conduction disorders and bundle branch block. In patients with sick sinus syndrome, only very old women (> or = 85 years) had more atrial systems implanted than men of similar age (6.5% vs 3.5%), whereas men received more double chamber pacemakers (12.3% vs 10.3%) (P = 0.002). However, the relative distribution of physiological versus nonphysiological pacemakers in this subgroup was similar for men and women. In patients with chronic atrial fibrillation/flutter associated with bradycardia, sex differences were only apparent in the age group of 75-85 years; women received more dual chamber pacemakers (8.8% vs 5.3%) whereas men received more single chamber ventricular pacemakers (94.2% vs 89.8%) (P = 0.0011). With increasing age, sex differences in pacemaker selection were absent, but there was a considerable drop in implantation rate of dual chamber systems. Our study showed no major sex differences in the selection of pacemaker devices. Physicians select pacemaker devices by age rather than gender, which might be a rational choice.     

Long-Term Thrombosis after Transvenous Permanent Pacemaker Implantation

To assess the efficacy of prophylactic administration of anticoagulant and antiaggregant drugs to prevent venous thrombosis after long-term transvenous permanent pacemaker implantation, venograms were performed in 100 consecutive patients at the elective replacement of the pacemaker. Mean follow-up period after initial transvenous permanent pacemaker implantation was 6.0 years. The venograms demonstrated normal in 77 patients. The remaining 23 venograms showed venous stenosis in 11 patients and total obstruction in 12 patients. Twenty-one of these 23 patients had venous collateral circulation. No difference was found in the incidence of venous abnormalities according to the route of entry, the lead insulation, the total number of the implanted leads, and anticoagulant and antiaggregant drugs. All these patients have remained asymptomatic. In conclusion, the incidence of venous thrombosis after long-term transvenous pacing is 23% and the causes of venous thrombosis may be endothelial trauma and underlying venous stenosis. As this article describes a retrospective limited study, we cannot find the efficacy of prophylactic administration of anticoagulant and antiaggregant drugs to prevent venous thrombosis formation after transvenous permanent pacemaker implantation. Further prospective study will be needed to assess the efficacy of prophylactic administration of anticoagulant and antiaggregant drugs.     

Permanent Pacemaker Implantation Following Cardiac Surgery: Indications and Long-Term Follow-Up

Background: Conduction disturbances requiring permanent pacemaker implantation after heart surgery occur in about 1.5% of patients. Early pacemaker implantation may reduce morbidity and postoperative hospital stay. We reviewed our experience with patients undergoing surgery to try and identify predictors for pacemaker requirements and patients who will remain pacemaker dependent.
Methods: We performed a retrospective review of 4,999 patients undergoing surgery between the years 1993 and 2005. Patient age was 64 ± 12 years, and 71% were males. Coronary bypass was performed in 4,071 (81%), aortic valve replacement in 675 (14%), and mitral valve replacement in 968 (18%) patients.
Results: Seventy-two patients (1.4%) required implantation of a permanent pacemaker after surgery. Indications for pacemaker implantation included complete atrioventricular block in 59, symptomatic bradycardia/slow atrial fibrillation in nine, second-degree atrioventricular block in two, and other conduction disturbances in two patients. Predictors for pacemaker requirement by multivariate analysis were left bundle branch block and aortic valve replacement (P < 0.001). Late follow-up was available in 58 patients, at 72 ± 32 months. Thirty-seven (63%) were pacemaker dependent. Predictors for late pacemaker dependency were third-degree atrioventricular block after surgery and preoperative left bundle branch block (P < 0.001).
Conclusions: Patients at high risk for pacemaker implantation after heart surgery include those with preexisting conduction disturbances, and those undergoing aortic valve replacement. Of those receiving a pacemaker, about one-third will recover at late follow-up. For patients in the high-risk group who are pacemaker dependent after surgery, we recommend implanting a permanent pacemaker at 5 days after surgery, thus enabling early mobilization and early discharge.     

Thirty-one years of clinical experience with "nuclear-powered" pacemakers

From 1973 through 1987, 164 radioisotope powered ("nuclear") pacemakers were implanted in 139 patients at the Newark Beth Israel Medical Center. Patient survival was much as might be expected from an age group as selected for this program. At 31 years (January 2005), 12 of the 139 patients (9%) were still alive. The experience reported here encompassed a span of 16 years of implantation with a follow-up of slightly more than 31 years. The problems encountered along the way were not remarkably different from those encountered in general clinical experience with pacemakers, except that the number of reoperations was fewer. In fact, most patients died with the initial implant in place. Deaths most commonly were due to cardiac causes (54%). The frequency of malignancies was similar to that of the age-matched population; primary tumor sites were randomly distributed. These results show that nuclear pacemakers were safe and reliable. Their longevity and the resulting decrease in reoperations offset their greater initial cost.     

A New Multiprogrammable Isotopic Powered Cardiac Pacemaker

A new multiprogrammable, isotopic-powered cardiac pacemaker was implanted in six patients as a custom device. Five were initial implants and one was a replacement. The patients were studied for up to two years. In five of the six cases it was found advantageous to change one of the programmable parameters. Multiprogrammability is obviously as important in an isotopic pulse generator as in a lithium unit, if not more so, because of the unit's greater longevity. Further studies are continuing in an FDA approved clinical trial.     

Atrioventricular Block Occurring Late After Heart Transplantation: Presentation of Three Cases and Literature Review

Sinus node dysfunction is a well-known occurrence following orthotopic heart transplantation, but atrioventricular block is rarely described. We compare the incidence and clinical presentation of atrioventricular block and sin us node dysfunction among the first 200 consecutive patients receiving heart transplantation at the University of Utah. Two of 200 patients (1%) required pacemaker implantation for symptomatic atrioventricular block compared to 13 of 200 (6.5%) who required pacemaker for symptomatic sinus node dysfunction. Of the patients with atrioventricular block, one had intermittent Mobitz II second-degree atrioventricular block and one had high grade atrioventricular block without ventricular escape. The most striking difference between the patients with atrioventricular block and those with sinus node dysfunction was the interval between transplantation and pacemaker implantation; time to pacemaker implantation in the atrioventricular block patients was 955 and 810 days compared to a median time of 26 days for sinus node dysfunction patients (P = 0.037). The patients requiring permanent pacemaker implantation were similar to those not requiring pacemaker implantation with respect to age, sex, ischemic time, and donor age. None of the patients requiring permanent pacemaker implantation was on amiodarone therapy within 2 months of transplant.     

Longevity of dual chamber pacemakers: device and patient related determinants

In 382 patients with three different dual chamber pulse generators, the median time interval to battery depletion was 98.3 months. Cox regression analysis revealed the following variables as significant predictors of battery longevity: programmed pacing rate, energy of the stimulation output, mode of stimulation (i.e., proportion of paced cycles in one or two chambers), battery capacity, and internal sensing current of the pacemaker. Although 27% of all patients died before the service life of the pacemaker was over and despite a rate of premature reoperations of 8.6%, the majority of pacemaker patients (55%) fully used the expected battery life span of the pulse generator. Patients who died before the pacemaker had reached its end of service were significantly older at implantation than patients who survived until pacemaker replacement. The vast majority (92%) of patients received another dual chamber pulse generator when replacement was required. These data underline the need for long-lasting dual chamber devices.     

Implantable Cardioverter Defibrillator Implanted by Nonthoracotomy Approach: Initial Clinical Experience with the Redesigned Transvenous Lead System

Standard implantation procedure for the implantable Cardioverter defibrillator (ICD) has traditionary required a thoracotomy approach. A newly revised nonthoracotomy defibrillator lead system that uses a single transvenous tripolar endocardial lead alone or in combination with a subcutaneous/submuscular patch lead was introduced into clinical trials in September, 1990. Fourteen patients requiring a Cardioverter defibrillafor for recurrent sustained ventricular tachycardia (eight patients) or aborted sudden cardiac death (six patients) were evaluated for implantation of this lead system. Primary successful lead system implantation was obtained in nine patients. The remaining five patients had unacceptably high defibrillation thresholds (DFTs) for implantation. One of the nine initially successful implants demonstrated unacceptable DFTs and cross-talk inhibition from a permanent pacemaker necessitating removal of the nonthoracotomy lead system and replacement with a conventional lead system via thoracotomy. All remaining primary implanted patients experienced successful conversion of induced ventricular fibrillation prior to hospital discharge. Continued follow-up and greater experience to confirm the durability and efficacy of the nonthoracotomy AICD lead system are needed.     

Initial results with left ventricular pacemaker lead implantation using a preformed "peel-away" guiding sheath and "side-wire" left ventricular pacing lead

We report our preliminary experience with the use of preformed "peel-away" guiding sheaths and "side-wire" pacing leads for permanent biventricular pacemaker insertion in 13 patients with heart failure. Three of these patients were undergoing an upgrade of a preexistent VVIR pacing system after prior His ablation for medically refractory atrial fibrillation. Six of the patients had undergone attempted biventricular pacemaker insertion, but required left ventricular lead repositioning after total implantation failure or late displacement of the lead. The remaining patients were undergoing new system implantation. Target vessel cannulation was achieved in all patients. However, in one patient, diaphragmatic pacing throughout the target vessel length prevented successful implantation. All other implants were ultimately successful (92% success rate). We conclude that device implantation using a preformed sheath and side-wire pacing lead is feasible and may offer significant benefits over implantation with currently available technology.     

心脏起搏器植入患者手术前后 C-反应蛋白变化及意义

目的：研究永久性心脏起搏器植入患者手术前后血清C-反应蛋白（CRP）动态变化及其临床意义。方法采用酶联免疫吸附试验测定60例永久性心脏起搏器植入患者术前,术后第1、3、7天血清中CRP含量,分析不同植入类型起搏器与CRP的关系。结果本组60例,男34例,女26例,平均年龄（51．8±5．3）岁,分别植入单腔和双腔起搏器各30例。与术前比较,所有患者术后CRP含量均显著升高,差异有统计学意义（P＜0．05）,术后第1天显著升高,术后第3天达到高峰,术后第7天仍升高,与第1天相似。亚组分析：植入单腔和双腔起搏器患者年龄,男女比例,高血压、冠心病及糖尿病患者数均相当,两组术前、术后血清CRP含量差异无统计学意义（P＞0．05）,单腔起搏器植入者术后较双腔起搏器植入者轻微升高。结论心脏起搏器植入术可使患者血清CRP含量显著升高并持续至少1周,手术创伤可诱发或加重炎症。     

Pacemaker Dependency After Coronary Artery Bypass

A retrospective study was carried out on 36 patients (33 males and 3 females) to determine the incidence of WI pacemaker dependency following coronary artery bypass surgery. Pacemaker dependency was defined as the presence of pacemaker activity when pacing rate was programmed at 50 beats/min and/or when no hemodynamic adequate rhythm was present during pulse generator replacement. The patients were divided into two groups: (group I) 26 patients with complete atrioventricular (AV) block developing in the early postoperative period. In most of them a pacemaker was implanted up to 3 weeks following surgery (range 2 days to 1 year); (group II) ten patients in whom the indication for pacemaker implantation was sick sinus syndrome with sinus arrest and/or tachy-bradycardia. These patients underwent pacemaker implantation at varying periods of time following surgery (range 12 days to 4 years). Unipolar endocardial leads with VVI programmable pacemakers were implanted in all patients included in this study. Mean follow-up time was 3 years. In group I the pacemaker dependency rate was 65%, whereas in group II it was 30% throughout the follow-up period. It is concluded that the low incidence of pacemaker dependency in patients who undergo pacemaker implantation after coronary bypass surgery necessitates frequent evaluation in the nondependent patient, in order to reassess the need for the pacemaker before pulse generator replacement. Such reassessment should probably include prolonged ambulatory monitoring as well as invasive evaluation of the conduction system, if avoidance of pulse generator replacement is considered.     

The incidence and risk factors for venous obstruction after implantation of transvenous pacing leads

Several investigators have shown that the incidence of venous obstruction after pacemaker implantation was observed in 31-50% of pacemaker patients. However, these previous reports did not investigate the venous system prior to implantation. The aim of this study was to determine the incidence and risk factors for venous obstruction in patients with transvenous pacing leads. The study included 131 consecutive patients (64 men, 67 women; mean age 71.3 +/- 9.8 years) who were investigated using intravenous digital subtraction angiography (DSA) before and after permanent pacemaker implantation. Follow-up DSA was performed for a mean interval of 44 +/- 6 months after pacemaker lead implantation in 79 of 131 patients. A diameter narrowing > 60% was defined as an obstruction. Prior to implantation of pacing leads, venous obstruction was present in 18 (13.7%) of 131 patients. In 15 of these 18 patients, the obstruction was present at the site of the left innominate vein. Follow-up DSA, after implantation of pacing leads, showed that venous obstruction was observed in 26 (32.9%) of 79 patients. There were no significant differences between obstruction and nonobstruction groups in terms of age, sex, cardiothoracic ratio, left atrial dimension, left ventricular ejection fraction, baseline heart diseases for indication of pacemaker implantation, or number and body size of pacing leads. Neither clinical symptoms nor abnormal physical findings were observed in any patients. In conclusion, the incidence of venous obstruction after pacing lead implantation is less than that of previous reports, which might be related to the incidence of venous obstruction before pacing leads implantation.     

Cardiac pacing in children

Advances in pacemaker technology over the last 25 years have made cardiac pacing in infants and children a safe and practical therapy. Some of the technical challenges encountered with the first permanent pacemaker implantation in children during the early 1960s have been solved with miniaturized generators, lithium batteries, noninvasive programmability, and improved placement techniques. This chapter reports common causes of bradydysrhythmias in children, reviews the indications for permanent pacemaker implantation in children, describes current pacing systems appropriate for children, and identifies nursing implications and potential pacemaker complications unique to children.     

Feasibility of Long-Term Electrocardiographic Monitoring with an Implanted Device for Syncope Diagnosis

Patients with infrequent recurrent syncope undiagnosed after extensive noninvasive and invasive testing pose a diagnostic and therapeutic dilemma. The purpose of this pilot study was to assess the feasibility of using an implanted, long-term monitor as an aid to diagnosis in these patients. This was done using commercially available pacemakers with monitoring functions. Sixteen patients (eight males and eight femaiesj, aged 59.7 ± 17 years who had unexplained syncope despite a 12-lead electrocardiogram, repeated Holter monitoring, exercise testing, echocardiography, an eJectro-physioJogical study, and a tiJf test (n = 6), were entered into the study. Patients had experienced a mean of 3.3 ± 1 episodes of syncope in the 12 months prior to the study. All provided a history suggestive of Stokes-Adams attacks and were referred for consideration of pacemaker implantation. Two patients had ischemic heart disease and one patient had a long QT interval. Patients had an Intermedics Nova II or Medtronic Quintech DPG pulse generator capable of recording sensed and paced events implanted with a single right ventricular lead. Syncope or presyncope occurred in ten patients (62%) 4.9 ± 4.2 months after pacemaker implantation. Bradycardia was detected in six patients and four patients had no arrhythmia. In addition to bradycardia, one patient also had tachycardia detected. Pacing therapy resulted in symptom relief in all six patients with syncope or presyncope due to bradycardia. Complications of pacemaker implantation (lead insulation failure) occurred in two patients. One of these patients subsequently had an infection of the generator pocket with associated systemic sepsis. Although the devices used in this study have serious limitations, the results suggest that continuous long-term electrocardiographic monitoring can be useful in patients with recurrent syncope and a negative diagnostic work-up. A smaller device with self-contained electrodes designed for this purpose would be required for wider applicability.     

A Cephalic Vein Cutdown and Venography Technique to Facilitate Pacemaker and Defibrillator Lead Implantation

TSE, H.–F., et al. : A Cephalic Vein Cutdown and Venography Technique to Facilitate Pacemaker and Defibrillator Lead Implantation. The aim of this study was to assess the feasibility of a cephalic vein cutdown and venography technique for implantation of a pacemaker or ICD and to determine the causes of failure of cephalic vein cutdown. In consecutive patients who underwent pacemaker or ICD implants, a modified cephalic vein guidewire technique was performed. This technique was attempted in 289 pacemaker implants and 26 ICD implants (155 men, 160 women; mean age  74 ± 10 years  ). The success rate for implantation of a single chamber and a dual chamber device by using this technique alone was 84% (54/64) and 74% (185/251), respectively (  P = 0.10  ). In an additional 7% of patients with dual chamber implant, the cephalic vein can be used for passage of the ventricular lead. A cephalic venogram was required in 82 patients and facilitated the passage of the guidewire in 62 (79%) of them. No complication related to vascular access was observed with this technique. This technique failed in 54 (17%) of 315 patients due to (1) failure of cephalic vein isolation (48%), (2) venous stenosis (24%), or (3) venous torturosity or anomalies (28%). There were no significant differences in the patient's age, sex, type of device, and the fluoroscopic time for lead placement between patients with or without successful lead placement using this technique (all  P > 0.05  ). In conclusion, a simple modification of the cephalic vein guidewire technique together with venography has facilitated the placement of leads during pacemaker and ICD implant. This technique is safe and applicable in the majority of patients and avoids the risk of subclavian puncture.     

Health-related quality of life in pacemaker patients: a single and multidimensional self-rated health comparison study.

Since implantation of the first permanent pacemaker in 1958, significant advances have been made in pacemaker technology. To date, however, health-related quality of life (HRQoL) in a large pacemaker population has not been investigated. With dwindling clinical resources, it is important to study HRQoL in a pacemaker population in a reliable and straightforward manner. This study aimed to determine and compare single and multidimensional self-rated health (SRH) in a pacemaker population in terms of sociodemographic characteristics, pacemaker mode and symptoms. The findings showed that irrespective of whether the perspective was single or multidimensional, this Swedish pacemaker population (n=697) with a mean age of 76 years had an acceptable HRQoL. Men, aged 65-84 years, persons who were cohabiting, who had their own dwelling, who had a DDD or who had a pacemaker for 相似文献   

Nine-year Experience during 1973–1982 with 1,060 Pacemakers in 805 Patients

Our experience with over one-thousand pacemaker implantations resulting in almost 28,000 patient pacing months is reviewed. Data are presented regarding changing indications for pacing, experience with numerous pacemaker types, patient survival, comparative mortality of sick sinus syndrome and complete heart block, and telephone surveillance. Consistent with some previous reports, there were high one- and two-year post-implant mortality rates, and advanced age at implant was associated with decreased survival. Males had a significantly higher mortality rate. The period reported covers the transition from utilization of mercury-zinc batteries to lithium power cells and other new technology; significant differences were observed in device reliability and patient mortality when comparing these eras. Certain patients evidenced disparate survivals, the most notable difference being seen in those who received their primary implants prior to 1976 and subsequent implants of more modern units.     

Influence of D-net (EUROPEAN GSM-standard) cellular telephones on implanted pacemakers in children

This study was designed to evaluate possible interactions between digital cellular telephones and implanted pacemakers in children. The study comprised 95 patients (53 males and 42 females) with a mean age of 11.5 +/- 4.6 years (range 1-22 years). The average time from pacemaker implantation was 2.5 years (range 1 month-12 years). Fourteen (15%) devices were dual chamber and the remaining were single chamber pacemakers. The following companies manufactured the pacemakers tested: Medtronic (n = 42), Telectronics (n = 9), Vitatron (n = 16), Pacesetter (n = 19), CPI (n = 8), and Biotronik (n = 1). All the patients were tested in the supine position during continuous ECG monitoring. After completion of the routine pacemaker check, the effects of the European Global system for mobile communication (GSM) was tested using two cellular telephone models (Ericsson GA 628 and Siemens S 25, 2-W power). For this purpose, atrial and ventricular sensitivity settings were programmed to the most sensitive values, and the tests were carried out in the unipolar and bipolar sensing modes. The evaluation was performed during ringing, switching on/off, and conversation phase with the cellular telephone positioned over the pulse generator and around the pacemaker pocket. A malfunction of the pacemaker was not observed in any patient. Only 1 (1%) of 95 patients showed a brief oversensing problem during calls with the cellular telephone. In this case, an AAIR pacemaker was implanted transvenously in a subcutaneous pocket and the sensing defect occurred only with the unipolar sensing mode and was not reproducible. Once the source of interference was removed, no sensing defect was detected and the patient remained asymptomatic. No symptoms were experienced in this study. The authors believe that pacemaker dependent patients with nonprotected pulse generators manufactured at the beginning of 1990s may be tested by their physicians for possible interferences before they use a digital cellular telephone.     

Radioisotopic Pacemaker: Long-Term Clinical Results

In order to prolong the service life of the generator, the isotopic pacemakers, powered by Pu²³⁸, have been developed and implanted since 1970. We report the follow-up of 325 patients (mean age 39 ± 18 years) implanted with an isotopic pulse generator (Medtronic 9000/9090) between April 1970 and July 1982. The mean follow-up was 12 years (range 6 days to 18.5 years). The generator was highly reliable; the mean value of pacing rate between implantation and last follow-up decreased significantly but no more than 1 beat/min (72.7 vs 71.8 beats/ min; P < 0.001) and the pulse width did not change significantly. The actuarial survival of the device was 97% at 18.5 years. During the follow-up period, 122 reoperations were performed in 85 patients: 88 explanations of the entire pacing system and 34 modifications of the lead system. Lead dysfunction accounted for 68% of the 122 reoperations, generator failure for 6%, and miscellaneous reasons for 26%. However, 72% of patients remain free of intervention during the follow-up period and 61 patients (20%) died during this period. Most deaths (52%) were of nonsudden cardiovascular origin, 17% were related to cancer, and 13% to sudden death. After 5, 10, and 18.5 years, 94%, 89%, and 73% of the patients were alive, respectively. No side effect could be attributed to the radioisotope. We conclude that this isotopic pacemaker demonstrated its reliability for long-term cardiac pacing.     

Postpacemaker implant pericarditis: incidence and outcomes with active-fixation leads

Pericarditis has been noted as a potential complication of pacemaker implantation. This study evaluated the risk of developing pericarditis following pacemaker implantation with active-fixation atrial leads. Included were 1,021 consecutive patients (mean age 73.4+/-0.4 years, range 16-101 years; 45.2% women) undergoing new pacemaker system implantation between 1991 and 1999 who were reviewed for the complication of pericarditis. The incidence and outcomes of postimplantation pericarditis in patients receiving active-fixation atrial leads were compared to those not receiving these leads. Of 79 patients who received active-fixation atrial leads, 4 (5%) developed pericarditis postpacemaker implantation. Of 942 patients with passive-fixation atrial leads or no atrial lead (i.e., a ventricular lead only), none developed pericarditis postoperatively (P < 0.001). Of patients receiving active-fixation ventricular leads only (n = 97), none developed pericarditis. No complications were apparent at the time of implantation in patients who developed pericarditis. Pleuritic chest pain developed between 1 and 28 hours postoperatively. Three patients had pericardial rubs without clinical or echocardiographic evidence of tamponade. They were treated conservatively with acetylsalicylic acid or ibuprofen and their symptoms resolved without sequelae in 1-8 days. One patient (without pericardial rub) died due to cardiac tamponade on postoperative day 6. Postmortem examination revealed hemorrhagic pericarditis with no gross evidence of lead perforation. Pericarditis complicates pacemaker implantation in significantly more patients who receive active-fixation atrial leads. It may be precipitated byperforation of the atrial lead screw through the thin atrial wall. Patients developing postoperative pericarditis should befollowed closely due to the risk of cardiac tamponade.