Acute complications of permanent pacemaker implantation: their financial implication and relation to volume and operator experience

Quality of care: not hospital but operator volume of pacemaker implantations counts

Literature about pacemaker (PM) implantations shows that several clinical and technical factors determine the short- and long-term complications after the intervention. Annual hospital volume, however, does not negatively affect complications in contrast with the cumulative experience of the operator. In view of this observation, the current required number of 20 to 30 first PM implantations for cardiology training does not match standards for quality of care. In addition, concentration of implants and replacement of pacemakers to a limited number of operators per hospital to comply with the increasing demands of patients and other parties has to be seriously considered.

Complications after cardiac implantable electronic device implantations: an analysis of a complete, nationwide cohort in Denmark

Aims

Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient morbidity, healthcare costs, and possibly increased mortality.

Methods and results

Population-based cohort study in all Danish patients who underwent a CIED procedure from May 2010 to April 2011. Data on complications were gathered on review of all patient charts while baseline data were obtained from the Danish Pacemaker and ICD Register. Adjusted risk ratios (aRRs) with 95% confidence intervals were estimated using binary regression. The study population consisted of 5918 consecutive patients. A total of 562 patients (9.5%) experienced at least one complication. The risk of any complication was higher if the patient was a female (aRR 1.3; 1.1–1.6), underweight (aRR 1.5; 1.1–2.3), implanted in a centre with an annual volume <750 procedures (0–249 procedures: aRR 1.6; 1.1–2.2, 250–499: aRR 2.0; 1.6–2.7, 500–749: aRR 1.5; 1.2–1.8), received a dual-chamber ICD (aRR 2.0; 1.4–2.7) or CRT-D (aRR 2.6; 1.9–3.4), underwent system upgrade or lead revision (aRR 1.3; 1.0–1.7), had an operator with an annual volume <50 procedures (aRR 1.9; 1.4–2.6), or underwent an emergency, out-of-hours procedure (aRR 1.5; 1.0–2.3).

Conclusion

CIED complications are more frequent than generally acknowledged. Both patient- and procedure-related predictors may identify patients with a particularly high risk of complications. This information should be taken into account both in individual patient treatment and in the planning of future organization of CIED treatment.

Rate, causes, and impact on patient outcome of implantable device complications requiring surgical revision: large population survey from two centres in Italy

AIMS

The long-term impact of implantable device-related complications on the patient outcome has not been thoroughly evaluated. The aims of this retrospective, bi-centre study were to analyse the rate and nature of device-related complications requiring surgical revision in a large series of patients undergoing device implantation, elective generator replacement and pacing system upgrade and to systematically assess the impact of such complications on patient outcome and healthcare utilization.

METHODS AND RESULTS

Data from 2671 consecutive procedures (1511 device implantations, 1034 elective generator replacements, and 126 pacing system upgrades) performed between January 2006 and March 2011 were retrospectively analysed. The outcome measures recorded were complication-related mortality, number of re-operations, need for complex surgical procedures, number of re-hospitalizations, and additional hospital treatment days. Over a median follow-up of 27 months, the overall rate of complications was 2.8% per procedure-year [9.5% in cardiac resynchronisation therapy (CRT) device implantation, 6.1% in pacing system upgrade, 3.5% in implantable cardioverter defibrillator implantation, 1.7% in pacemaker implantation, and 1.7% in generator replacement). The procedure with the highest risk of complications was CRT device implantation (odds ratio: 6.6; P < 0.001); these complications primarily involved coronary sinus lead dislodgement and device infection. Patients with complications had a significantly higher number of device-related hospitalizations (2.3 ± 0.6 vs. 1.0 ± 0.1; P < 0.001) and hospital treatment days (15.7 ± 25.1 vs. 3.6 ± 1.1; P < 0.001) than those without complications. Device infection was the complication with the greatest negative impact on patient outcome.

CONCLUSION

Cardiac resynchronisation therapy implantation was the procedure with the highest risk of complications requiring surgical revision. Complications were associated with substantial clinical consequences and a significant increase in the number and length of hospitalizations.

Outcomes of cardiac resynchronization therapy in the elderly

BACKGROUND

Octogenarians (>80 years) have been underrepresented in clinical trials of cardiac resynchronization therapy (CRT).

OBJECTIVE

To determine the benefit of CRT with or without a defibrillator in older elderly patients.

METHODS

We retrospectively studied consecutive patients who received CRT at our institution from 2002 through 2008. New York Heart Association (NYHA) class and echocardiographic parameters were assessed before and after CRT. Thirty-day complications after device implant were collected. Survival data were obtained from the national death and location database. Data were compared between those 80 years and younger and those older than 80 years.

RESULTS

Of 728 patients identified, 90 (12.4%) were older than 80 years. After CRT, older and younger patients had similar improvements in NHYA class (P = 0.41), ejection fraction (P = 0.48), and mitral valve regurgitation (MR) severity (P = 0.42). In the older patients, defibrillator implantation was associated with comparable improvement in NYHA class, ejection fraction, and MR grade severity (P > 0.05), as in those without a defibrillator. Overall survival was worse in octogenarians than in the younger patients by Kaplan-Meier estimates (P = 0.001). Multivariate analysis showed similar survival between the younger and older subjects (hazard ratio, 1.23; 95% confidence interval, 0.83-1.84; P = 0.31). The observed complication rate in all study subjects was 12.2%, with no difference between the two age groups.

CONCLUSION

Octogenarian patients who received CRT with or without a defibrillator for advanced heart failure had similar clinical benefits as younger patients. CRT should not be withheld from octogenarians meeting current selection guidelines.

Recurrent strokes caused by a malpositioned pacemaker lead

This case report illustrates the case of a patient who developed recurrent strokes after a pace maker lead was inserted into his left ventricle. It was removed successfully by the cardiothoracic surgeons but he remained very dependent functionally. This case highlights the importance of always reviewing the electrocardiogram and chest radiograph after the insertion of a pacemaker as late diagnosis of this complication can leave the patient with significant morbidity.

Pneumothorax in cardiac pacing: a population-based cohort study of 28,860 Danish patients

AIM

To identify risk factors for pneumothorax treated with a chest tube after cardiac pacing device implantation in a population-based cohort.

METHODS AND RESULTS

A nationwide cohort study was performed based on data on 28 860 patients from the Danish Pacemaker Register, which included all Danish patients who received their first pacemaker (PM) or cardiac resynchronization device from 1997 to 2008. Multiple logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals for the association between risk factors and pneumothorax treated with a chest tube. The median age was 77 years (25th and 75th percentile: 69-84) and 55% were male (n = 15 785). A total of 190 patients (0.66%) were treated for pneumothorax, which was more often in women [aOR 1.9 (1.4-2.6)], and in patients with age >80 years [aOR 1.4 (1.0-1.9)], a prior history of chronic obstructive pulmonary disease [aOR 3.9 (1.6-9.5)], implantation of a dual-chamber PM [aOR 1.5 (1.0-2.2)], venous access with subclavian vein puncture [aOR 7.8 (4.9-12.5)], venous access with both subclavian vein puncture and cephalic vein cut-down [aOR 5.7 (3.0-10.8)], and implantation in a non-university centre [aOR 2.1 (1.6-2.9)].

CONCLUSION

Pneumothorax treated with a chest tube remains a clinically important problem in device therapy. The cephalic vein cut-down technique should be applied whenever possible to avoid this complication.

Physician procedure volume and complications of cardioverter-defibrillator implantation

BACKGROUND

The outcomes of procedures are often better when they are performed by more experienced physicians. We assessed whether the rate of complications after implantable cardioverter-defibrillator (ICD) placement varied with the volume of procedures a physician performed.

METHODS AND RESULTS

We studied 356 515 initial ICD implantations in the National Cardiovascular Data Registry-ICD Registry, performed by 4011 physicians in 1463 hospitals. We examined the relationship between physician annual ICD implantation volume and in-hospital complications, using hierarchical logistic regression to adjust for patient characteristics, implanting physician certification, hospital characteristics, hospital annual procedure volume, and the clustering of patients within hospitals and by physician. We repeated this analysis for ICD subtypes: single chamber, dual chamber, and biventricular. There were 10 994 patients (3.1%) with a complication after ICD implantation, and 1375 died (0.39%). The complication rate decreased with increasing physician procedure volume from 4.6% in the lowest quartile to 2.9% in the highest quartile (P<0.0001), and the mortality rate decreased from 0.72% to 0.36% (P<0.0001). The inverse relationship between physician procedure volume and complications remained significant after adjusting for patient, physician, and hospital characteristics (OR 1.55 for complications in lowest-volume quartile compared with highest; 95% confidence interval, 1.34-1.79; P<0.0001). This inverse relationship was independent of physician specialty and of hospital volume, was consistent across ICD subtypes, and was also evident for in-hospital mortality.

CONCLUSION

Physicians who implant more ICDs have lower rates of procedural complications and in-hospital mortality, independent of hospital procedure volume, physician specialty, and ICD type.

Pacemaker implantation in small hospitals: complication rates comparable to larger centres

Aims

Some countries have a demography that makes it necessary to maintain relatively small pacemaker centres. We wanted to assess the quality of pacemaker surgery in two such hospitals.

Methods and results

Through patient records we gathered information on ∼535 consecutive primary pacemaker implantations in two small pacemaker centres with 30 and 80 annual operations, respectively. All patients were followed for 3 years. All complications documented in the patient records were registered. Furthermore, we performed a non-systematic literature search comparing our data with reports from major centres published over the last 10 years.We found 72 complications in 64 (12.0%) of the patients, the most common being bleeding, lead failure, and pneumothorax. If minor bleedings without any consequences for the patients are excluded, the number of complications was 46 in 40 patients (7.5%). We had to reoperate on 5.2% of the patients. There was no statistically significant difference in complication rates between the two hospitals. Education candidates generated statistically significant more complications than experienced doctors (13.7 vs. 7.1%, P < 0.05).

Conclusion

There are no generally accepted norms of complication rates in pacemaker surgery. However, we found no indications that our centres have a rate of complications that is unacceptably high.

Risk factors for lead complications in cardiac pacing: a population-based cohort study of 28,860 Danish patients

BACKGROUND

Lead complications are the main reason for reoperation after implantation of pacemakers (PM) or cardiac resynchronization therapy (CRT-P) devices.

OBJECTIVE

This study sought to describe the incidence of lead complications causing reoperation after device implantation and to identify risk factors for lead complications.

METHODS

A nationwide, population-based, historic cohort study was performed based on data from the Danish Pacemaker Register, which includes all Danish patients who received their first PM or CRT-P device from 1997 to 2008. Follow-up occurred 3 months after implantation.

RESULTS

The study population consisted of 28,860 patients. The incidence of any lead complication was 3.6%, encompassing right atrial (RA; 2.3%), right ventricular (2.2%), and left ventricular (4.3%) lead complications. The lead complication risk declined during the first part of the study period and remained stable after 2002. Multivariate analysis identified the following significant risk factors: chronic heart failure as indication (adjusted odds ratio (aOR) 3.0; 95% confidence interval [CI] 2.1 to 4.3), implantation in a nonuniversity center (aOR 1.4; 95% CI 1.2 to 1.6), inexperienced operator with <25 implantations (aOR 1.6; 95% CI 1.3 to 2.0), single-lead RA device (aOR 1.4; 95% CI 1.1 to 1.8), dual-chamber pacing device (aOR 1.6; 95% CI 1.4 to 1.9), CRT-P device (aOR 3.3; 95% CI 2.4 to 4.4) and passive-fixation RA lead (aOR 2.2; 95% CI 1.7 to 2.9).

CONCLUSION

Lead complications causing reoperation remain a clinically important problem in device therapy. Mainly procedure-related factors were identified as independent risk factors for lead complications.

The relation between hospital procedure volume and complications of cardioverter-defibrillator implantation from the implantable cardioverter-defibrillator registry

OBJECTIVES

We sought to examine the relationship between hospital implantable cardioverter-defibrillator (ICD) implantation volume and procedural complications in a contemporary, representative population.

BACKGROUND

Hospitals that perform higher volumes of procedures generally have better clinical outcomes.

METHODS

We examined initial ICD implantations between January 2006 and December 2008 at hospitals participating in the NCDR (National Cardiovascular Data Registry) ICD Registry and evaluated the relationship between hospital annual implant volume and in-hospital adverse outcomes.

RESULTS

The rate of adverse events declined progressively with increasing procedure volume (p trend < 0.0001). This relationship remained significant (p trend < 0.0001) after adjustment for patient clinical characteristics, operator characteristics, and hospital characteristics. The volume-outcome relationship was evident for all ICD subtypes, including single-chamber (p trend = 0.004), dual-chamber (p trend < 0.0001), and biventricular ICDs (p trend = 0.02).

CONCLUSIONS

Patients who have an ICD implanted at a high-volume hospital are less likely to have an adverse event associated with the procedure than patients who have an ICD implanted at a low-volume hospital.

Risk of Hematoma Complications After Device Implant in the Clopidogrel Era

Background—

Device implant pocket hematoma is a recognized complication after permanent pacemaker (PM) and implantable cardioverter-defibrillator (ICD) implantation. Pocket hematoma is associated with local discomfort, an increased risk of infection, and may require surgical intervention or lead to lengthier hospital stays. The purpose of the study was to identify the clinical factors associated with hematoma formation after PM or ICD device implantation.

Methods and Results—

The subjects of this prospective observational study were 935 consecutive patients at Beaumont Hospital who underwent implantation of a PM or an ICD. Clinical characteristics and anticoagulant/antiplatelet drug use were recorded. A pocket hematoma was documented in 89 of 935 patients. Significant predictors of device pocket hematoma included ongoing clopidogrel therapy (18.3% on therapy, 10.5% recently discontinued, and 7.9% off therapy; P <0.001) and use of intravenous heparin (22.0% on therapy versus 8.2%; P <0.0001). Patients in whom clopidogrel was discontinued >4 days before device implantation had no hematoma. Hematomas occur more frequently in patients receiving ICDs than those receiving PMs. Device pocket hematoma was associated with an increased median length of hospital stay (4 days [interquartile range, 1 to 9] days with versus 2 days [ interquartile range, 1 to 6] days without hematoma; P =0.004) and increased late complications or surgical intervention.

Conclusions—

The use of clopidogrel or intravenous heparin significantly increased the risk of hematoma at the time of PM or ICD implantation. By withholding clopidogrel before surgery, the excess risk of bleeding complications may be reduced.

Gender differences in procedure-related adverse events in patients receiving implantable cardioverter-defibrillator therapy

BACKGROUND

Women are at higher risk than men for adverse events with certain invasive cardiac procedures. Our objective was to compare rates of in-hospital adverse events in men and women receiving implantable cardioverter- defibrillator (ICD) therapy in community practice.

METHODS AND RESULTS

Using the National Cardiovascular Data Registry ICD Registry, we identified patients undergoing first-time ICD implantation between January 2006 and December 2007. Outcomes included in-hospital adverse events after ICD implantation. Multivariable analysis assessed the association between gender and in-hospital adverse events, with adjustment for demographic, clinical, procedural, physician, and hospital characteristics. Of 161,470 patients, 73% were male, and 27% were female. Women were more likely to have a history of heart failure (81% versus 77%, P<0.01), worse New York Heart Association functional status (57% versus 50% in class III and IV, P<0.01), and nonischemic cardiomyopathy (44% versus 27%, P<0.01) and were more likely to receive biventricular ICDs (39% versus 34%, P<0.01). In unadjusted analyses, women were more likely to experience any adverse event (4.4% versus 3.3%, P<0.001) and major adverse events (2.0% versus 1.1%, P<0.001). In multivariable models, women had a significantly higher risk of any adverse event (OR 1.32, 95% CI 1.24 to 1.39) and major adverse events (OR 1.71, 95% CI 1.57 to 1.86).

CONCLUSIONS

Women are more likely than men to have in-hospital adverse events related to ICD implantation. Efforts are needed to understand the reasons for higher ICD implantation-related adverse event rates in women and to develop strategies to reduce the risk of these events.

Fatal complications of pacemaker and implantable cardioverter-defibrillator implantation: medical malpractice?

OBJECTIVES

Pacemaker implantation has become a routine procedure in modern cardiology, and implantable cardioverter-defibrillators are implanted with rising frequency. Although fatal complications are relatively rare, they may give rise to malpractice lawsuits against medical personnel. The objective was to identify fatal complications after pacemaker and implantable cardioverter-defibrillators implantation and to evaluate the legal consequences in alleged malpractice cases.

METHODS

Retrospective analysis of all 27,730 autopsy cases performed at the Institute of Legal Medicine, Hamburg, Germany, between January 1983 and June 2007. Study cases were identified using the keywords 'cardiac death', 'malpractice', 'complications', 'pacemaker' and 'implantable cardioverter-defibrillator'.

RESULTS

Eleven pacemaker-related and four implantable cardioverter-defibrillator-related fatalities where lawsuits had been filed were identified. A causal connection between the procedure and fatal outcome was confirmed by autopsy in six cases. Malpractice or violation of the rules of good medical practice could be excluded in all cases. All inquiries were abandoned.

CONCLUSION

Fatal complications after pacemaker and implantable cardioverter-defibrillator implantation attributable to medical malpractice are extremely rare. The study illustrates the importance of a medico-legal autopsy in alleged fatal malpractice cases.

Cardiac device implantation in the United States from 1997 through 2004: a population-based analysis

OBJECTIVE

Use of cardiac devices has been increasing rapidly along with concerns over their safety and effectiveness. This study used hospital administrative data to assess cardiac device implantations in the United States, selected perioperative outcomes, and associated patient and hospital characteristics.

METHODS

We screened hospital discharge abstracts from the 1997-2004 Healthcare Cost and Utilization Project Nationwide Inpatient Samples. Patients who underwent implantation of pacemaker (PM), automatic cardioverter/defibrillator (AICD), or cardiac resynchronization therapy pacemaker (CRT-P) or defibrillator (CRT-D) were identified using ICD-9-CM procedure codes. Outcomes ascertainable from these data and associated hospital and patient characteristics were analyzed.

MEASUREMENTS AND MAIN RESULTS

Approximately 67,000 AICDs and 178,000 PMs were implanted in 2004 in the United States, increasing 60% and 19%, respectively, since 1997. After FDA approval in 2001, CRT-D and CRT-P reached 33,000 and 7,000 units per year in the United States in 2004. About 70% of the patients were aged 65 years or older, and more than 75% of the patients had 1 or more comorbid diseases. There were substantial decreases in length of stay, but marked increases in charges, for example, the length of stay of AICD implantations halved (from 9.9 days in 1997 to 5.2 days in 2004), whereas charges nearly doubled (from $66,000 in 1997 to $117,000 in 2004). Rates of in-hospital mortality and complications fluctuated slightly during the period. Overall, adverse outcomes were associated with advanced age, comorbid conditions, and emergency admissions, and there was no consistent volume-outcome relationship across different outcome measures and patient groups.

CONCLUSIONS

The numbers of cardiac device implantations in the United States steadily increased from 1997 to 2004, with substantial reductions in length of stay and increases in charges. Rates of in-hospital mortality and complications changed slightly over the years and were associated primarily with patient frailty.

Successful conservative management with positive end-expiratory pressure for massive haemothorax complicating pacemaker implantation

Haemothorax resulting from injury to a great vessel is a potential complication during transvenous pacemaker implantation that can be caused by perforation by the electrode. If the amount of bleeding is massive, control needs thoracotomy. We report on a 70-year-old man who had a massive haemothorax following transvenous pacemaker implantation. This complication was controlled successfully by using positive end-expiratory pressure (PEEP). We conclude that this simple but reproducible experience may offer effective haemostasis for a massive haemothorax caused by transvenous catheter perforation.

The Incidence of Reoperations in Pacemaker Recipients

OBJECTIVE

To evaluate the incidence of reoperation due to complications or battery depletion in patients who underwent endocardial permanent pacemaker implantation during an 8-year period.

METHODS

All pacemaker implantation and related procedures from January 1996 to June 2003 were retrospectively collected and entered into a database. During this time period a total number of 3856 operations with 2242 primary implantations and 1614 redo operations were performed at our department. As 809 patients were referred from another hospital, where the primary operation was done, these patients were excluded from further analysis. The mean follow-up time was 48 months, ranging from 6 to 96 months.

RESULTS

A total of 547 patients underwent 805 reoperations during this 8-year period. The most common cause for reoperation was lead malfunction, which occurred in 326 patients (8.4%). Atrial leads were affected more commonly (206 patients, 63%) than ventricular leads (120 patients, 37%). Eighty percent of lead failure occurred during the first 3 months after implantation and was due to dislocation of the lead, whereas the remaining 20% occurred more than 3 months after implantation and were caused by lead fracture, insulation failure, and exit block. Elective replacement indication of a pacemaker was necessary in 312 patients (8%), and pacemaker pocket erosion or infection required reoperation in 167 patients (4%).

CONCLUSION

Permanent pacemaker implantation is now accepted as a highly effective and safe procedure. However, cost effectiveness and the relatively simple procedure have to be weighed against the need of reoperations due to system malfunction or replacement indication.

The frequency and incremental cost of major complications among medicare beneficiaries receiving implantable cardioverter-defibrillators

OBJECTIVES

We aimed to quantify the frequency and nature of early complications after implantable cardioverter-defibrillator (ICD) implantation in general practice, and estimate the incremental costs of those complications to the health care system.

BACKGROUND

Cardioverter-defibrillator implantation rates are rising quickly. Little has been published regarding the outcomes and costs of these procedures in unselected populations.

METHODS

Using Medicare Provider Analysis and Review (MedPAR) files, we identified 30,984 admissions containing procedure codes for new ICD or cardiac resynchronization therapy defibrillator implantation in fiscal year 2003. The frequencies of eight complicating diagnoses during these admissions were determined. Length of stay (LOS) and total hospital costs, derived using whole-hospital cost to charge ratios, were calculated for each admission. The incremental effects of any and each complication on LOS and hospital cost were estimated in multivariable models, adjusting for demographic factors and comorbid conditions.

RESULTS

The mean cost for all admissions was 42,184 dollars (median 37,902 dollars) with mean LOS of 4.7 days (median 2.0 days). One or more complications were coded in 10.8% of admissions, most commonly "mechanical complication of the ICD" and hemorrhage/hematoma. The occurrence of any complication increased adjusted LOS by 3.4 days and costs by 7,251 dollars. Each of the individual complications was associated with highly significant increases in both LOS (1 to 10 days) and hospital cost (5,000 dollars to 20,000 dollars).

CONCLUSIONS

In fiscal 2003, 10.8% of Medicare patients undergoing cardioverter-defibrillator implantation experienced one or more early complications, associated with significant increases in LOS and costs. Efforts to reduce these complications could have significant clinical and financial benefits.

Modelling the health benefits and economic implications of implanting dual-chamber vs. single-chamber ventricular pacemakers in the UK

AIMS

To estimate the consequences of managing bradycardia due to sinoatrial node disease or atrioventricular block with dual-chamber vs. single-chamber ventricular pacemakers.

METHODS AND RESULTS

A discrete-event simulation was conducted to predict outcomes over 5 years. Patients could develop post-operative complications, clinically relevant pacemaker syndrome leading to replacement of single-chamber with dual-chamber, atrial fibrillation (AF; which if chronic might require anticoagulants) or stroke. Survival, quality-adjusted life years (QALYs), complications, and associated direct medical costs were estimated (2003 British Pounds pounds sterling). Identical patients were simulated after receiving a single-chamber device or a more expensive dual-chamber pacemaker. Probabilities of conditions were obtained from clinical trials. Benefits were discounted at 1.5% and costs at 6%. Post-operative complications increased from 6.4% with single-chamber to 7.7% with dual-chamber but AF decreased (22 vs. 18%) as did clinically relevant pacemaker symptoms (16.8 vs. 0%). Approximately 4300 pounds sterling were accrued per patient over 5 years. Additional health benefits with dual-chamber are achieved at a mean net cost of 43 pounds sterling per patient, leading to 0.09 QALY with a cost-effectiveness ratio of 477 pounds sterling/QALY.

CONCLUSION

Implanting the costlier device increases the cost of the initial operation; however, this is expected to be offset by a reduction in costs associated with re-operations and AF.

Prophylactic pacemaker use to allow beta-blocker therapy in patients with chronic heart failure with bradycardia

BACKGROUND

Although the benefits of beta-blocker therapy for patients with congestive heart failure (CHF) are independent of pretreatment heart rate, patients with chronic systolic heart failure and low resting heart rates are often excluded from beta-blocker therapy. We investigated the effectiveness and cost-effectiveness of prophylactic pacemaker insertion to facilitate beta-blocker use in these patients.

METHODS

A Markov model simulated the natural history of a cohort of clinically stable patients with CHF (ejection fraction < or = 35%, mean age 60 years) with resting heart rates of < 68 beat/min. Two strategies were evaluated: (1) conventional therapy (conventional)-the risks for death and hospitalization were derived from the angiotensin-converting enzyme inhibitor arm of the SOLVD treatment trial; and (2) pacemaker insertion with atrial pacing and carvedilol therapy (pacemaker-carvedilol)-risk reductions for death and CHF-related hospitalizations for carvedilol compared with conventional therapy were derived from the US Carvedilol Heart Failure Study. We assumed full carvedilol benefits for 2 years, declining benefits for the next 3 and no additional benefits after 5 years, whereas pacemaker-related adverse events persisted.

RESULTS

In the base case, the pacemaker-carvedilol strategy increased mean survival by 1.3 years at an incremental cost of $7800, for an incremental cost-effectiveness of $6100 per year of life saved. Results were most sensitive to theoretical pacing-induced harm, changes in hospitalization cost, and reductions in beta-blocker benefits.

CONCLUSION

Prophylactic pacemaker insertion to facilitate beta-blocker treatment in patients with CHF with low resting heart rates has the potential to produce clinical benefits in a highly cost-effective manner.

Early mobilization after pacemaker implantation

BACKGROUND

There are no international guidelines indicating how long a patient should stay strictly in bed after pacemaker implantation. In the present study, we tested a new protocol concerning the mobilization of patients 3 h after receiving a single or a dual-chamber pacemaker.

METHODS

Consecutive patients who underwent single or dual-chamber pacemaker implantation were randomized to a 3 or 24 h immobilization protocol. Only bipolar passive fixation leads were computed. After the implant, an elastic bandage was put on the homolateral shoulder of all patients for 24 h. A complete clinical and electronic follow-up was performed before discharge and repeated 2 months later. End-points considered were the displacement of the lead, high pacing thresholds (> 3.5 V/0.4 ms at the discharge or > 2.5 V/0.4 ms at the 2-month follow-up), sensing defects not corrigible by programming and clinical complications of the pocket

RESULTS

One hundred and thirty-four patients were included in the study: 57 in group A (mobilization after 3 h) and 77 in group B (24 h). In group A, one haematoma and two displacements occurred in three patients. In group B, we registered one haematoma, one subclavian vein thrombosis, three displacements and three high stimulation thresholds. No statistical differences were observed between the end-points of group A versus B.

CONCLUSIONS

The present study shows that an early mobilization protocol is feasible because no statistical differences resulted from the two groups of study as regards clinical outcome, complications and electronic measurements of the implanted devices, which have been followed up for 2 months.

The relation between patients' outcomes and the volume of cardioverter-defibrillator implantation procedures performed by physicians treating Medicare beneficiaries

OBJECTIVES

The purpose of this study is to determine if implantable cardioverter-defibrillator (ICD) implantation should be limited to physicians with high procedural volume.

BACKGROUND

Expanding indications for ICDs will result in an increasing number of physicians implanting these devices.

METHODS

Using the 20% Part B Medicare files for 1999 through 2001, we identified new ICD implantations and the corresponding denominator files. We used Medicare Provider Analysis and Review hospital records and the appropriate International Classification of Diseases-9 diagnosis and procedure codes to define complications within 90 days. We defined physician volume categories by assigning one-quarter of the patients to each quartile. A logistic regression model was used to adjust outcomes for potential confounders.

RESULTS

Ninety-day mortality did not differ between patients who had their ICD implanted by physicians with the highest volume of implants and those who had their ICD implanted by physicians with the lowest volume of implants (6.2% vs. 5.9%; odds ratio [OR] 0.99; 95% confidence interval [CI] 0.75 to 1.30). Within 90 days, mechanical complications were significantly higher in the lowest volume quartile (OR 1.47; 95% CI 1.09 to 1.99) but were comparable for physicians who implanted at least 11 ICDs per year. The risk of ICD infection was significantly higher in patients who had their ICD implanted by physicians with the lowest volume of implants (OR 2.47; 95% CI 1.18 to 5.17).

CONCLUSIONS

We observed an association between a higher volume of ICD implants and a lower rate of mechanical complications and infections. This association suggests that ICD implantation should not be performed by physicians without regard to their procedural volume.

Update on implantable pacemakers

There are currently more than 3 million patients worldwide with implanted pacemakers, and indications for implants are expanding. Pacemakers today are smaller (23-30 g) and fashioned in a more physiologic shape so as to be less obtrusive. They are replete with sophisticated diagnostic and programming features that make troubleshooting of complicated arrhythmias easier. Advanced nurse clinicians need to have a basic understanding of pacemaker function, indications for implantation, an awareness of potential complications, and facility with basic troubleshooting. The purpose of this article is to describe the features of the pacemakers available today and approaches to troubleshooting these devices.

Do prehospital discharge pacemaker checks provide any additional clinical benefit?

We performed a retrospective analysis of 250 records of consecutive, newly implanted, pacemaker patients from a single center to determine the rate of postimplant complications and observations discovered before and during the prehospital discharge evaluation. No observations occurred in 246 of 250 patients (98.4%) (1-sided 95% confidence interval 96.4%). Of the 250 patients, 4 had observations that were discovered at the prehospital discharge check and required reprogramming to increase the sensitivity safety margin (3 atrial and 1 ventricular). We documented only 1 complication that was discovered before the predischarge evaluation through telemetry and resulted in an atrial lead revision.

Long term complications in single and dual chamber pacing are influenced by surgical experience and patient morbidity

OBJECTIVE

To determine how short and long term complication rates after pacemaker implantation are influenced by patient morbidity, operator experience, and choice of pacing system.

DESIGN

Retrospective analysis of 1884 patients who received VVI (n = 610), VDD (n = 371), or DDD devices (n = 903) between 1990 and 2001. Follow up period was 64 (34) months. The influence of age, sex, coronary artery disease, myocardial infarction, reduced left ventricular (LV) function, right ventricular (RV) dilatation, atrial fibrillation, device type, and operator experience on operation time and complication rate were analysed.

RESULTS

Operation time was prolonged in patients with coronary artery disease, inferior myocardial infarction, reduced LV function, and RV dilatation. Implantation of DDD pacemakers prolonged operation time, particularly among operators with a low or medium level of experience. The overall complication rate was 4.5%. Sixty seven per cent of these complications occurred within the first three months. Complication rate was increased by age, reduced LV function, and RV dilatation. Implantation of DDD systems led to a higher complication rate (6.3%) than implantation of VVI (2.6%) or VDD pacemakers (3.2%). These differences were present only among operators with a low or medium level of experience.

CONCLUSIONS

Operation time and complication rate increased with age, impaired LV function, and RV dilatation. Complication rates were higher with DDD than with VVI or VDD implantation and were excessive among inexperienced but not experienced operators.

[Hemothorax in a 78-year-old woman]

We report an atypical presentation of hemothorax. Tamponade and subacute dyspnea occurred secondary to a wound of the right atrium caused by a pacemaker electrode in 78-year-old woman on oral anticoagulants for complete arrhythmia due to atrial fibrillation. This case illustrate an unusual pathophysiological mechanism of hemothorax.

Pocket Hematoma After Pacemaker or Implantable Cardioverter Defibrillator Surgery

STUDY OBJECTIVES

Pocket hematoma is a common complication after pacemaker or implantable cardioverter defibrillator (ICD) implantation. Thus, we investigated the influence of patient comorbidity, implantation strategy, operator experience, antiplatelet therapy, and anticoagulation therapy on hematoma rate.

DESIGN

Between 1990 and 2002, a total of 3,164 devices (pectoral pacemakers, 2,792; ICDs, 372) were implanted at our institution. Predictors of hematoma occurrence were determined prospectively and were analyzed by multivariate regression analysis. Operator experience was graded by individual implantation number, as follows: low, < 50; medium, 50 to 100; and high, > 100.

RESULTS

The incidence of pocket hematoma was 4.9%, leading to prolonged hospitalization in 2.0% of all patients. Reoperation for pocket hematoma was required in 1.0% of patients. High-dose heparinization (hazard ratio [HR], 4.2), combined acetylsalicylic acid (ASA)/thienopyridine treatment after coronary stenting (HR, 5.2), and low operator experience (HR, 1.6) were independently predictive of hematoma development. Therapy with ASA alone did not increase the hematoma rate compared to patients who did receive antiplatelet or anticoagulation therapy (3.1% vs 2.5%, respectively; difference not significant). In patients with nonvalvular atrial fibrillation, postoperative high-dose heparinization substantially increased the hematoma rate (10.7% vs 2.9%, respectively; p < 0.001) without reducing the rate of arterial embolism within the first month after implantation (0.18% vs 0.21%, respectively; difference not significant). The infection rate (0.28% within 3 months after implantation) was not influenced by the presence of the pocket hematoma.

CONCLUSIONS

The use of high-dose heparinization and combined ASA/thienopyridine treatment are highly predictive for the occurrence of intraoperative bleeding and pocket hematoma in patients who have undergone pacemaker and ICD surgery. We propose recommendations for the management of antiplatelet and anticoagulation therapy in patients undergoing these interventions.

Vascular Emergencies of the Thorax after Blunt and Iatrogenic Trauma: Multi–Detector Row CT and Three-dimensional Imaging

Multi-detector row computed tomographic (CT) angiography is an effective modality for vascular imaging in the thorax. It allows acquisition of high-resolution data sets during a single breath hold, making it the preferred method for evaluation of patients with acute vascular disease. In contrast to conventional angiography, multirow CT angiography not only depicts the vessels but also allows assessment of adjacent structures. Multirow CT angiography with two- and three-dimensional reformation can be used to diagnose vascular emergencies of the thorax after blunt and iatrogenic trauma. These include incomplete and complete aortic rupture; traumatic aortic dissection; arterial dissection and rupture after minor trauma in patients with Ehlers-Danlos syndrome; traumatic intramural hematoma; pseudoaneurysm after endovascular repair; injuries due to Swan-Ganz catheters; complications of central venous cannulation, pacemaker implantation, and percutaneous pericardial drainage; and foreign-body embolism. The diagnoses can be established with multirow CT angiography in the emergency department. Thus, the time to diagnosis can be considerably decreased by obviating conventional angiography. Knowledge of the CT findings in various vascular conditions is essential to make use of multirow CT angiography in combination with two- and three-dimensional reformation as an efficient and accurate diagnostic tool in emergency radiology.

Permanent Pacing Lead Insertion Through the Cephalic Vein Using an Hydrophilic Guidewire

The cephalic vein (CV) should be preferred to the subclavian vein for the insertion of permanent pacing leads because of better results. Unfortunately, the direct lead introduction using the standard CV cutdown is often unsuccessful. This study evaluated the efficacy and safety of a steerable hydrophilic guidewire (HGW) for lead insertion through the CV. An HGW was successfully introduced through the cephalic vein and into the subclavian vein. Over a 6-month period, 115 consecutive patients underwent pacemaker implantation. In nine (7.8%) patients, the cephalic vein did not allow lead or guidewire introduction. The direct introduction of the leads through the CV was successful in 55 (51.9%) of 106 patients. In 14 (12.2%) additional patients, a lead was inserted through the CV using a standard guidewire. The use of an HGW and of a split introducer allowed successful insertion of at least one lead in 35 (30.4%) additional patients. Overall, the HGW was successful in 35 (94.6%) of 37 of patients in which the technique was attempted. The CV approach was successful in 104 (90.4%) of 115 patients. In conclusion, the use of an HGW allows the insertion of a pacing lead through the CV in the great majority of patients in whom direct introduction and the use of a standard guidewire had failed. The technique significantly improves the success rate of the CV approach and may help to improve the acute and long-term results of permanent cardiac pacing.

Permanent Pacemakers:. Should Straightened Atrial Leads Be Repositioned?

The aim of this study was to assess if atrial leads whose "J" configuration has straightened significantly on the postprocedural chest X ray should be repositioned. Between January 1996 and December 1997, 445 patients underwent dual chamber pacemaker implantation at the Papworth Hospital. Postprocedural chest X rays were available in 410 of these. The degree of straightening of the tip of the atrial lead was assessed from the lateral chest X ray and was graded as mild (-10 to +10 degrees from the horizontal), moderate (+10 to +30 degrees), or severe (> or = +30 degrees). Patients were followed with regard to atrial sensing and pacing characteristics, lead displacements, and lead revisions. Fifty-two (12%) patients had some degree of straightening (graded mild, moderate, severe) of the atrial lead on the postprocedure chest X ray (passive fixation in 48, active 4). Of these, 12 patients underwent next day lead repositioning, 5 of whom had abnormalities of pacing and/or sensing parameters. Seven patients therefore underwent repositioning of the atrial lead despite normal pacing parameters in view of lead straightening alone. Of the 12 patients who underwent repositioning, 3 still had lead straightening after the second procedure. The cohort for follow-up consisted of 43 patients (24 [56%] men, age 69 +/- 11 years at the time of implant) who were left with significant atrial lead straightening but adequate atrial parameters. Straightening was mild in 26 patients, moderate in 10, and severe in 7 patients. At implant the P wave amplitude was 4.8 +/- 2.4 mV. Follow-up was for 4.8 +/- 2.1 years, a total of 178 patient years. At final follow-up, the P wave amplitude was 2.7 +/- 1.3 (P < 0.05 vs implant). Censoring events occurred in 16 cases, comprising 11 deaths (none suspected to be pacemaker or lead related), 3 cases of persistent atrial fibrillation, 1 system extraction for infection, and 1 lead extraction for erosion. There were no cases of inadequate atrial lead sensing or pacing in the remaining patients. Irrespective of the degree of lead straightening on the postoperative lateral chest X ray, atrial leads should not be repositioned unless there are abnormalities of pacing or sensing parameters.

Long-Term Complication Rates in Ventricular, Single Lead VDD, and Dual Chamber Pacing

A higher incidence of pacemaker related complications has been reported in DDD systems as compared to VVI devices. The implantation of single lead VDD pacemakers might reduce the complication rate of physiological pacing in patients with AV block. In a retrospective study, the data records of 1,214 consecutive patients with pacemaker implantation for AV block between 1990 and 2001 (VVI 36.5%, DDD 32.9%, VDD 30.6%) were analyzed. Complications requiring surgical interventions were compared during a follow-up period of 64 +/- 31 months. Operation and fluoroscopic times were longer in DDD pacemaker implantation compared to VDD and VVI devices:58 +/- 23 versus 39 +/- 10 and 37 +/- 13 minutes (P<0.001), 9.2 +/- 5.2 versus 4.1 +/- 2.4 and 3.5 +/- 2.3 minutes, respectively. Differences remained significant after correction for covariates. In a multivariate Cox regression model, the corrected complication hazard of a DDD pacemaker implantation was increased by 3.9 (1.4-11.3) compared to VVI and increased by 2.3 (1.1-4.5) compared to VDD pacing. Higher complication rates in DDD pacing were mainly due to a higher incidence of early reoperation for atrial lead dysfunction, whereas the long-term complication rate was not different from VDD or VVI pacing. Early and long-term complication rates did not differ between VDD and VVI pacemaker systems. In conclusion, operation time and complication rates of physiological pacing are reduced by VDD pacemaker implantation achieving values comparable to VVI pacing. Thus, single lead VDD pacing can be recommended for patients with AV block.

The management of surgical complications of pacemaker and implantable cardioverter-defibrillators

The rate of implantation of pacemakers and implantable cardioverter-defibrillators (ICDs) is ever-increasing. The relative ease of device implantation utilizing a relatively simple, expeditious, percutaneous approach, without the requirement for general anesthesia or long recuperation times, has fueled enthusiasm for implantation. However, the complication risk is ever-present and forms the subject of this pragmatic review, which is limited to the management of only the surgical complications of device implantation. The management of surgical complications related to the implantation of pacemakers and ICDs should include (1) awareness of potential complications, (2) a meticulous approach to the implantation procedure to avoid complications, (3) approach to diagnosis and (4) specific therapy. With a clear understanding of the accepted implant indications and potential complications, and a meticulous approach to the implant and post implant follow up, the incidence of complications can be minimized.