Cost-effectiveness of the implantable cardioverter-defibrillator versus antiarrhythmic drugs in survivors of serious ventricular tachyarrhythmias: results of the Antiarrhythmics Versus Implantable Defibrillators (AVID) economic analysis substudy

Economic evaluation in cardiac electrophysiology: Determining the value of emerging technologies

Cardiac electrophysiology is a constantly evolving speciality that has benefited from technological innovation and refinements over the past several decades. Despite the potential of these technologies to reshape patient care, their upfront costs pose a challenge to health policymakers who are responsible for the assessment of the novel technology in the context of increasingly limited resources. In this context, it is critical for new therapies or technologies to demonstrate that the measured improvement in patients' outcomes for the cost of achieving that improvement is within conventional benchmarks for acceptable health care value. The field of Health Economics, specifically economic evaluation methods, facilitates this assessment of value in health care. In this review, we provide an overview of the basic principles of economic evaluation and provide historical applications within the field of cardiac electrophysiology. Specifically, the cost-effectiveness of catheter ablation for both atrial fibrillation (AF) and ventricular tachycardia, novel oral anticoagulants for stroke prevention in AF, left atrial appendage occlusion devices, implantable cardioverter defibrillators, and cardiac resynchronization therapy will be reviewed.

Long-Term Outcomes for Out-of-Hospital Cardiac Arrest in Elderly Patients: An Analysis of Cardiac Arrest Registry to Enhance Survival Data Linked to Medicare Files

BACKGROUND

Most studies on out-of-hospital cardiac arrest have primarily focused on in-hospital or short-term survival. Little is known about long-term outcomes and resource use among survivors of out-of-hospital cardiac arrest.

METHODS

In this observationsl study, we describe overall long-term outcomes for patients from the national Cardiac Arrest Registry to Enhance Survival linked to Medicare files to create the Cardiac Arrest Registry to Enhance Survival: Mortality, Events, and Costs for Cardiac Arrest survivors dataset. Cardiac Arrest Registry to Enhance Survival data between 2013 and 2019 were linked to Medicare data using probabilistic matching algorithms. Overall long-term mortality, readmissions, and index hospitalization costs are reported for the overall cohort.

RESULTS

Among 56 425 patients who were 65 years of age or older in Cardiac Arrest Registry to Enhance Survival who survived to hospital admission, 26 875 (47.6%) were successfully linked to Medicare files. Mean (+SD) cost of the index hospitalization was $23 262+$24 199 and the median cost was $14 636 (interquartile range, $9930-$30 033). Overall, 8676 (32.3%) survived to hospital discharge with 38.0% discharged home, 11.8% to hospice care, and the remaining 50.2% to other inpatient, skilled nursing care, or rehabilitation facilities. Mortality after discharge was initially high (27.0% at 3 months) and then increased gradually, with 1- and 3-year mortality of 37.1% and 50.1%, respectively. During the first year, 40.1% were readmitted at least once, with 19.7% readmitted on > 1 occasion.

CONCLUSIONS

The Cardiac Arrest Registry to Enhance Survival: Mortality, Events, and Costs for Cardiac Arrest survivors registry includes rich data on postdischarge outcomes and resource utilization. Use of this dataset will enable future investigations on the long-term effectiveness, costs, and cost-effectiveness of various interventions for out-of-hospital cardiac arrest in elderly patients.

Recent temporal trends in hospital costs for non-surgical patients receiving implantable cardioverter defibrillators

PURPOSE

Many studies have analyzed the cost-effectiveness of implantable cardioverter defibrillators (ICDs), but hospital costs have not been as thoroughly reported. This study reviewed the associated hospital costs for non-surgical patients who received ICDs from 2015 to 2019.

METHODS

We performed a retrospective single-center analysis of patients who received an ICD between 2015 and 2019. ICD cost was analyzed with respect to time using linear regression t-test analysis.

RESULTS

For 304 patients, we trended cost of the devices over time. 168 (55.2%) cases were single-chamber devices, 53 (17.4%) were dual-chamber, 59 (19.4%) were cardiac resynchronization therapy-defibrillators (CRT-D), and 24 (7.9%) were subcutaneous devices. The cost of all ICDs decreased by -$1.82/day (p<0.001), R² = 0.056. By type, cost of single-chamber devices decreased by -$2.56/day (p<0.001), R² = 0.47, dual-chamber ICD by -$3.50/day (p<0.001), R² = 0.51, CRT-D by -$4.07/day (p<0.001), R² = 0.47, and subcutaneous by -$3.33/day (p<0.001), R² = 0.83.

CONCLUSION

This is the first detailed analysis of ICD costs that we are aware of. The cost of all ICDs decreased modestly and became much greater when categorized by type. Overall hospital cost associated with ICD implantation did not show a significant trend, but total supply cost showed a significant decrease over time.

[Preclinical management of cardiac arrest-extracorporeal cardiopulmonary resuscitation]

BACKGROUND

The chances of surviving out-of-hospital cardiac arrest (OHCA) are still very low. Despite intensive efforts the outcome has remained relatively poor over many years. In specific situations, new technologies, such as extracorporeal cardiopulmonary resuscitation (eCPR) could significantly improve survival with a good neurological outcome.

OBJECTIVE

Does the immediate restoration of circulation and reoxygenation via eCPR influence the survival rate after OHCA? Is eCPR the new link in the chain of survival?

MATERIAL AND METHODS

Discussion of current study results and guideline recommendations.

RESULTS

The overall survival rates after OHCA have remained at 10-30% over many years. Despite low case numbers more recent retrospective studies showed that an improved outcome can be achieved with eCPR. In selected patient collectives survival with a favorable neurological outcome is possible in 38% of the cases.

CONCLUSION

Survival after cardiac arrest and the subsequent quality of life dependent on many different factors. The time factor, i.e. the avoidance of a no-flow phase and reduction of the low-flow phase is of fundamental importance. The immediate restoration of the circulation and oxygen supply by eCPR can significantly improve survival; however, large randomized, controlled trials are currently not available.

Implantable cardiac defibrillators for people with non-ischaemic cardiomyopathy

BACKGROUND

There is evidence that implantable cardioverter-defibrillator (ICD) for primary prevention in people with an ischaemic cardiomyopathy improves survival rate. The evidence supporting this intervention in people with non-ischaemic cardiomyopathy is not as definitive, with the recently published DANISH trial finding no improvement in survival rate. A systematic review of all eligible studies was needed to evaluate the benefits and harms of using ICDs for primary prevention in people with non-ischaemic cardiomyopathy.

OBJECTIVES

To evaluate the benefits and harms of using compared to not using ICD for primary prevention in people with non-ischaemic cardiomyopathy receiving optimal medical therapy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and the Web of Science Core Collection on 10 October 2018. For ongoing or unpublished clinical trials, we searched the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), and the ISRCTN registry. To identify economic evaluation studies, we conducted a separate search to 31 March 2015 of the NHS Economic Evaluation Database, and from March 2015 to October 2018 on MEDLINE and Embase.

SELECTION CRITERIA

We included randomised controlled trials involving adults with chronic non-ischaemic cardiomyopathy due to a left ventricular systolic dysfunction with an ejection fraction of 35% or less (New York Heart Association (NYHA) type I-IV). Participants in the intervention arm should have received ICD in addition to optimal medical therapy, while those in the control arm received optimal medical therapy alone. We included studies with cardiac resynchronisation therapy when it was appropriately balanced in the experimental and control groups.

DATA COLLECTION AND ANALYSIS

The primary outcomes were all-cause mortality, cardiovascular mortality, sudden cardiac death, and adverse events associated with the intervention. The secondary outcomes were non-cardiovascular death, health-related quality of life, hospitalisation for heart failure, first ICD-related hospitalisation, and cost. We abstracted the log (hazard ratio) and its variance from trial reports for time-to-event survival data. We extracted the raw data necessary to calculate the risk ratio. We summarised data on quality of life and cost-effectiveness narratively. We assessed the certainty of evidence for all outcomes using GRADE.

MAIN RESULTS

We identified six eligible randomised trials with a total of 3128 participants. The use of ICD plus optimal medical therapy versus optimal medical therapy alone decreases the risk of all-cause mortality (hazard ratio (HR) 0.78, 95% confidence interval (CI) 0.66 to 0.92; participants = 3128; studies = 6; high-certainty evidence). An average of 24 patients need to be treated with ICD to prevent one additional death from any cause (number needed to treat for an additional beneficial outcome (NNTB) = 24). Individuals younger than 65 derive more benefit than individuals older than 65 (HR 0.51, 95% CI 0.29 to 0.91; participants = 348; studies = 1) (NNTB = 10). When added to medical therapy, ICDs probably decrease cardiovascular mortality compared to not adding them (risk ratio (RR) 0.75, 95% CI 0.46 to 1.21; participants = 1781; studies = 4; moderate-certainty evidence) (possibility of both plausible benefit and no effect). Implantable cardioverter-defibrillator was also found to decrease sudden cardiac deaths (HR 0.45, 95% CI 0.29 to 0.70; participants = 1677; studies = 3; high-certainty evidence). An average of 25 patients need to be treated with an ICD to prevent one additional sudden cardiac death (NNTB = 25). We found that ICDs probably increase adverse events (possibility of both plausible harm and benefit), but likely have little or no effect on non-cardiovascular mortality (RR 1.17, 95% CI 0.81 to 1.68; participants = 1781; studies = 4; moderate-certainty evidence) (possibility of both plausible benefit and no effect). Finally, using ICD therapy probably has little or no effect on quality of life, however shocks from the device cause a deterioration in quality of life. No study reported the outcome of first ICD-related hospitalisations.

AUTHORS' CONCLUSIONS

The use of ICD in addition to medical therapy in people with non-ischaemic cardiomyopathy decreases all-cause mortality and sudden cardiac deaths and probably decreases mortality from cardiovascular causes compared to medical therapy alone. Their use probably increases the risk for adverse events. However, these devices come at a high cost, and shocks from ICDs cause a deterioration in quality of life.

Improving the Methods for the Economic Evaluation of Medical Devices

Medical devices (MDs) have distinctive features, such as incremental innovation, dynamic pricing, the learning curve and organisational impact, that need to be considered when they are evaluated. This paper investigates how MDs have been assessed in practice, in order to identify methodological gaps that need to be addressed to improve the decision-making process for their adoption. We used the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist supplemented by some additional categories to assess the quality of reporting and consideration of the distinctive features of MDs. Two case studies were considered: transcatheter aortic valve implantation (TAVI) representing an emerging technology and implantable cardioverter defibrillators (ICDs) representing a mature technology. Economic evaluation studies published as journal articles or within Health Technology Assessment reports were identified through a systematic literature review. A total of 19 studies on TAVI and 41 studies on ICDs were analysed. Learning curve was considered in only 16% of studies on TAVI. Incremental innovation was more frequently mentioned in the studies of ICDs, but its impact was considered in only 34% of the cases. Dynamic pricing was the most recognised feature but was empirically tested in less than half of studies of TAVI and only 32% of studies on ICDs. Finally, organisational impact was considered in only one study of ICDs and in almost all studies on TAVI, but none of them estimated its impact. By their very nature, most of the distinctive features of MDs cannot be fully assessed at market entry. However, their potential impact could be modelled, based on the experience with previous MDs, in order to make a preliminary recommendation. Then, well-designed post-market studies could help in reducing uncertainties and make policymakers more confident to achieve conclusive recommendations. © 2017 The Authors. Health Economics published by John Wiley & Sons, Ltd.

Cardiac Pacing and Defibrillation Devices: Cost and Effectiveness

Implantable cardiac pacing and defibrillation devices are effective and commonly used therapies for patients with cardiac rhythm disorders. Because device implantation is not easily reversible, as well as the high healthcare costs inherent in device use, a clear understanding of the clinical benefits relative to costs is essential for both appropriate clinical use and rational policy making. Cardiac implantable electronic devices (CIEDs) have been among the best-investigated therapies in medicine; these devices have been the topic of numerous clinical and economic evaluations during the past 30 years. However, many important questions remain unclarified. We review the evidence supporting the clinical benefits of CIEDs, including effectiveness in extending survival as well as improving quality of life. We also summarize the economic studies that have investigated costs associated with these devices and their overall cost effectiveness, and we highlight important potential areas for future research.

Economic evaluations of implantable cardioverter defibrillators: a systematic review

The aim of this paper was to review the cost-effectiveness studies of implantable cardioverter defibrillators (ICD) for primary or secondary prevention of sudden cardiac death (SCD). A systematic review of the literature published in English or Spanish was performed by electronically searching MEDLINE and MEDLINE in process, EMBASE, NHS-EED, and EconLit. Some keywords were implantable cardioverter defibrillator, heart failure, heart arrest, myocardial infarction, arrhythmias, syncope, sudden death. Selection criteria were the following: (1) full economic evaluations published after 1995, model-based studies or alongside clinical trials (2) that explored the cost-effectiveness of ICD with or without associated treatment compared with placebo or best medical treatment, (3) in adult patients for primary or secondary prevention of SCD because of ventricular arrhythmias. Studies that fulfilled these criteria were reviewed and data were extracted by two reviewers. The methodological quality of the studies was assessed and a narrative synthesis was prepared. In total, 24 studies were included: seven studies on secondary prevention and 18 studies on primary prevention. Seven studies were performed in Europe. For secondary prevention, the results showed that the ICD is considered cost-effective in patients with more risk. For primary prevention, the cost-effectiveness of ICD has been widely studied, but uncertainty about its cost-effectiveness remains. The cost-effectiveness ratios vary between studies depending on the patient characteristics, methodology, perspective, and national settings. Among the European studies, the conclusions are varied, where the ICD is considered cost-effective or not dependent on the study.

Implantable cardioverter defibrillators for the treatment of arrhythmias and cardiac resynchronisation therapy for the treatment of heart failure: systematic review and economic evaluation

BACKGROUND

This assessment updates and expands on two previous technology assessments that evaluated implantable cardioverter defibrillators (ICDs) for arrhythmias and cardiac resynchronisation therapy (CRT) for heart failure (HF).

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of ICDs in addition to optimal pharmacological therapy (OPT) for people at increased risk of sudden cardiac death (SCD) as a result of ventricular arrhythmias despite receiving OPT; to assess CRT with or without a defibrillator (CRT-D or CRT-P) in addition to OPT for people with HF as a result of left ventricular systolic dysfunction (LVSD) and cardiac dyssynchrony despite receiving OPT; and to assess CRT-D in addition to OPT for people with both conditions.

DATA SOURCES

Electronic resources including MEDLINE, EMBASE and The Cochrane Library were searched from inception to November 2012. Additional studies were sought from reference lists, clinical experts and manufacturers' submissions to the National Institute for Health and Care Excellence.

REVIEW METHODS

Inclusion criteria were applied by two reviewers independently. Data extraction and quality assessment were undertaken by one reviewer and checked by a second. Data were synthesised through narrative review and meta-analyses. For the three populations above, randomised controlled trials (RCTs) comparing (1) ICD with standard therapy, (2) CRT-P or CRT-D with each other or with OPT and (3) CRT-D with OPT, CRT-P or ICD were eligible. Outcomes included mortality, adverse events and quality of life. A previously developed Markov model was adapted to estimate the cost-effectiveness of OPT, ICDs, CRT-P and CRT-D in the three populations by simulating disease progression calculated at 4-weekly cycles over a lifetime horizon.

RESULTS

A total of 4556 references were identified, of which 26 RCTs were included in the review: 13 compared ICD with medical therapy, four compared CRT-P/CRT-D with OPT and nine compared CRT-D with ICD. ICDs reduced all-cause mortality in people at increased risk of SCD, defined in trials as those with previous ventricular arrhythmias/cardiac arrest, myocardial infarction (MI) > 3 weeks previously, non-ischaemic cardiomyopathy (depending on data included) or ischaemic/non-ischaemic HF and left ventricular ejection fraction ≤ 35%. There was no benefit in people scheduled for coronary artery bypass graft. A reduction in SCD but not all-cause mortality was found in people with recent MI. Incremental cost-effectiveness ratios (ICERs) ranged from £14,231 per quality-adjusted life-year (QALY) to £29,756 per QALY for the scenarios modelled. CRT-P and CRT-D reduced mortality and HF hospitalisations, and improved other outcomes, in people with HF as a result of LVSD and cardiac dyssynchrony when compared with OPT. The rate of SCD was lower with CRT-D than with CRT-P but other outcomes were similar. CRT-P and CRT-D compared with OPT produced ICERs of £27,584 per QALY and £27,899 per QALY respectively. The ICER for CRT-D compared with CRT-P was £28,420 per QALY. In people with both conditions, CRT-D reduced the risk of all-cause mortality and HF hospitalisation, and improved other outcomes, compared with ICDs. Complications were more common with CRT-D. Initial management with OPT alone was most cost-effective (ICER £2824 per QALY compared with ICD) when health-related quality of life was kept constant over time. Costs and QALYs for CRT-D and CRT-P were similar. The ICER for CRT-D compared with ICD was £27,195 per QALY and that for CRT-D compared with OPT was £35,193 per QALY.

LIMITATIONS

Limitations of the model include the structural assumptions made about disease progression and treatment provision, the extrapolation of trial survival estimates over time and the assumptions made around parameter values when evidence was not available for specific patient groups.

CONCLUSIONS

In people at risk of SCD as a result of ventricular arrhythmias and in those with HF as a result of LVSD and cardiac dyssynchrony, the interventions modelled produced ICERs of < £30,000 per QALY gained. In people with both conditions, the ICER for CRT-D compared with ICD, but not CRT-D compared with OPT, was < £30,000 per QALY, and the costs and QALYs for CRT-D and CRT-P were similar. A RCT comparing CRT-D and CRT-P in people with HF as a result of LVSD and cardiac dyssynchrony is required, for both those with and those without an ICD indication. A RCT is also needed into the benefits of ICD in non-ischaemic cardiomyopathy in the absence of dyssynchrony.

STUDY REGISTRATION

This study is registered as PROSPERO number CRD42012002062.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

The cost effectiveness of implantable cardioverter defibrillators: a systematic review of economic evaluations

BACKGROUND

Sudden cardiac death (SCD) is the most common cause of death in developed countries, with more than 3 million people dying yearly. Implantable cardioverter defibrillators (ICDs) are considered to be an effective treatment in the primary and secondary prevention of SCD; however, their cost is considerable and this poses questions regarding whether they are worth the investment relative to less expensive pharmacotherapy.

OBJECTIVE

The aim of this systematic review is to investigate existing evidence regarding the cost effectiveness of ICD therapy and to identify the key drivers of cost effectiveness, for the purpose of informing interested policy and decision makers.

METHODOLOGY

A systematic review of the literature concerning the cost effectiveness of ICDs was undertaken. Electronic databases, including PubMed, Cochrane and Health Economic Evaluations Database were searched based on appropriate terms and their combinations. Economic evaluation studies that examined the cost effectiveness of ICDs were selected and 34 were included for evaluation.

RESULTS

Findings from the present analysis show that ICD therapy, in properly selected patients who are at high risk of sudden cardiac death, is associated with similar or better cost-effectiveness ratios compared with other well accepted conventional treatments. The cost effectiveness of ICDs is influenced by several factors, including ICD efficacy and safety, impact on patient quality of life, device original implantation cost, frequency and cost of battery replacement, patient demographics and risk profile and analysis time horizon.

CONCLUSION

ICDs may represent a cost-effective option relative to pharmacotherapy in appropriately selected patient groups. The cost-effectiveness ratios appear to be at acceptable and comparable levels to other established treatments in cardiovascular and non-cardiovascular diseases. However, cost effectiveness is highly related to several factors and hence economic efficiency is highly dependent on conditions that need to be fulfilled for each individual case in medical practice. The aforementioned factors and technological advances imply that to ensure cost-effective use of ICD therapy, continuous research is needed.

Cost-effectiveness of heart failure therapies

Heart failure (HF) is a leading cause of morbidity and mortality worldwide. Management of HF involves accurate diagnosis and implementation of evidence-based treatment strategies. Costs related to the care of patients with HF have increased substantially over the past 2 decades, partly owing to new medications and diagnostic tests, increased rates of hospitalization, implantation of costly novel devices and, as the disease progresses, consideration for heart transplantation, mechanical circulatory support, and end-of-life care. Not surprisingly, HF places a huge burden on health-care systems, and widespread implementation of all potentially beneficial therapies for HF could prove unrealistic for many, if not all, nations. Cost-effectiveness analyses can help to quantify the relationship between clinical outcomes and the economic implications of available therapies. This Review is a critical overview of cost-effectiveness studies on key areas of HF management, involving pharmacological and nonpharmacological clinical therapies, including device-based and surgical therapeutic strategies.

Secondary prevention in heart failure

Although most recent investigations into sudden cardiac death prevention in heart failure patients have been focused on primary prevention, secondary indications for defibrillators and medical therapy remain vitally important in this complex patient group. Antiarrhythmic therapy is currently used primarily as adjuvant therapy to implantable defibrillators. Secondary prophylaxis defibrillator trials have shown clear benefit in preventing recurrent sudden cardiac death, despite concern over inappropriate shocks and the potential detrimental effects of appropriate shocks. Device programming for secondary prophylaxis can help ameliorate these issues. This article discusses these issues as well as the continued underuse of defibrillators in specific populations.

Analysis of willingness to pay for implantable cardioverter-defibrillator therapy

Despite being effective in the primary and secondary prevention of sudden cardiac arrest, the cost-effectiveness of implantable cardioverter-defibrillator (ICD) therapy remains debated. We attempted to estimate the value ICD recipients place on their ICD device. We used the contingent valuation method to evaluate the willingness to pay (WTP) and the cost benefit of ICD therapy in an unselected population of 237 recipients. A hypothetical scenario was presented to patients in which at the end of their current ICD no public reimbursement for the replacement would occur. Patients were asked to indicate their out-of-pocket WTP for a replacement ICD using a close-ended question format. Seven different "take-it-or-leave-it" bids were randomly varied and assigned to patients. Median WTP was calculated with nonparametric methods, and multiple logistic regression models were generated to identify factors associated with WTP. Only cost of the device was considered. Median WTP was estimated at CAN $4,125, which corresponds to 21% of the cost of the device (CAN $20,000). In multiple logistic regression analysis, a higher bid (odds ratio [OR] 0.95, 95% confidence interval [CI] 0.91 to 0.99, per CAN $1,000 increase) was associated with a lower WTP, whereas a higher gross family income (OR 2.3, 95% CI 0.9 to 9.0) and higher education (OR 2.2, 95% CI 0.9 to 5.1) were associated with a trend for higher WTP. In conclusion, ICD recipients would be willing to pay a substantial amount for a replacement ICD. Considering the expensive price of the device, ICD recipients value favorably the benefits provided by the ICD.

Does Medicare Have an Implicit Cost-Effectiveness Threshold?

Background. Despite the huge cost of the program, the Centers for Medicare and Medicaid Services (CMS) has maintained a policy that cost-effectiveness is not considered in national coverage determinations (NCDs). Objective. To assess whether an implicit cost-effectiveness threshold exists and to determine if economic evidence has been considered in previous NCDs. Methods. A literature search was conducted to identify estimates of cost-effectiveness relevant to each NCD from 1999—2007 (n = 103). The economic evaluation that best represented each coverage decision was included in a review of the cost-effectiveness of medical interventions considered in NCDs. Results. Of the 64 coverage decisions determined to have a corresponding cost-effectiveness estimate, 49 were associated with a positive coverage decision and 15 with a noncoverage decision. Of the positive decisions, 20 were associated with an economic evaluation that estimated the intervention to be dominant (costs less and was more effective than the alternative), 12 with an incremental cost-effectiveness ratio (ICER) of less than $50,000, 8 with an ICER greater than $50,000 but less than $100,000, and 9 with an ICER greater than $100,000. Fourteen of the sample of 64 decision memos cited or discussed cost-effectiveness information. Conclusions. CMS is covering a number of interventions that do not appear to be cost-effective, suggesting that resources could be allocated more efficiently. Although the authors identified several instances where cost-effectiveness evidence was cited in NCDs, they found no clear evidence of an implicit threshold.

[ICD therapy as secondary prevention]

Patients who survive out-of-hospital cardiac arrest or symptomatic ventricular tachyarrhythmias are at considerable risk of recurrence of these events and ultimately death. The implantation of an implantable cardioverter defibrillator (ICD) in patients with previous sustained ventricular tachyarrhythmias (VT) is considered secondary prevention of sudden cardiac death. The purpose of this review is to summarize the most important trials on secondary prevention with an ICD. The results from a meta-analysis showed a relative-risk reduction of 28% in overall mortality. Compared with amiodarone, an ICD provided maximal benefit for those patients with an ejection fraction between 20% and 35%. The results of the ICD trial demonstrate that there is clear evidence for the effectiveness of an ICD in patients with unstable VT; however, for patients with stable VT the results are less clear. Data on older patients are scant, and whether the survival benefit observed in the middle aged and younger-old also extend to older elderly patients with a more limited life span is less clear. Therefore, as the population becomes older, it is important to evaluate the safety, effectiveness, and the cost effectiveness of ICD implantation in this population. Guidelines are important and helpful to guide clinical decisions, but the indication for an ICD still remains an individual decision after evaluation of the risks and benefits for the individual patient. However, the patient needs to be involved, which emphasizes the importance of dialogue between the patient and physician.

Current status of implantable cardioverter-defibrillator therapy in heart failure

Sudden cardiac arrest is one of the leading causes of death in patients with heart failure (HF). The implantable cardioverter-defibrillator (ICD) is the only evidence-based treatment strategy for patients who have survived a life-threatening ventricular arrhythmic event. Randomized clinical trials have shown that specific subsets of HF patients with ischemic and nonischemic dilated cardiomyopathy benefit from ICD therapy for primary prevention of sudden cardiac arrest. Cardiac resynchronization therapy has become the device-based therapy of choice for improving symptoms and survival in severe HF patients with evidence of ventricular dyssynchrony. This review summarizes the current status of ICD therapy in treating HF patients based on randomized clinical trials and current practice guidelines.

Atrial fibrillation in patients with implantable defibrillators

Atrial fibrillation (AF) is common in patients who have implantable defibrillators and presents some unique challenges and opportunities. AF burden can be assessed more accurately, allowing for evaluation of therapy efficacy (drugs or ablation). It remains to be shown whether home monitoring of defibrillators to detect and treat AF more quickly can reduce cardiovascular and stroke end points. One major goal will be to reduce inappropriate shocks from atrial fibrillation. Otherwise, the goals of therapy remain the same-reduction of symptoms (including heart failure exacerbation and inappropriate implantable cardioverter defibrillator therapies) by controlling rate or rhythm and anticoagulation for stroke prophylaxis.

Cost-benefit analysis of primary prevention of sudden cardiac death with an implantable cardioverter defibrillator versus amiodarone in Canada

BACKGROUND

Clinical trials have shown that implantable cardioverter defibrillators are effective in primary prevention of sudden cardiac death (SCD) in patients with high risk profiles.

OBJECTIVES

To conduct a cost-benefit assessment of prevention of sudden cardiac death with an implantable cardioverter defibrillator (ICD) vs. amiodarone from the Canadian health-care system perspective.

METHODS

A simulation model that estimates the patient's course following an implantation with an ICD or initiation of amiodarone treatment was created. A thousand pairs of patients with identical characteristics in each treatment group, with similar demographic profiles as observed in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) were simulated. Based on the simulated individual patient characteristics, the model estimated the timing of severe arrhythmic events and deaths due to other causes and implemented the consequences at the time of the events. Patients might die at the time of severe arrhythmia (sudden cardiac death) or survive and become secondary prevention cases and be exposed to a higher risk of severe arrhythmia for the following 6 months. The rates of arrhythmia and death due to other causes were assumed to be the same, whereas the cases of fatality from severe arrhythmia differed between treatments. During the course of the simulation, the clinical (i.e., deaths) and economic outcomes were tallied for both treatment groups. All model parameters were obtained from the literature. The primary data source for clinical inputs was the published results of the SCD-HeFT trial which investigated the impact of ICDs on patients' survival in primary prevention of sudden cardiac deaths compared to amiodarone and conventional therapy. The value of a statistical life (CND$ 5.8 million) was obtained from an analysis previously performed by Health Canada. The direct medical costs and monetary value of lives saved were estimated over 5 years. Sensitivity analyses on key parameters were carried out. The most important study limitation was using two different sources to derive the age dependent clinical risks. This issue was resolved by calibrating the derived risks to account for the population differences.

RESULTS

The model predicted that the overall mortality would be reduced by 19.1% (7.1% absolute reduction) with ICD compared to amiodarone over 5 years. The incremental benefit with ICD was estimated at CND$526,700 and additional cost at CND$28,300, which translated into a 0.05 cost: benefit ratio--around 1: 20 return of investment.

CONCLUSION

In Canada, ICDs are a worthwhile alternative to amiodarone in the primary prevention of sudden cardiac death.

Interpreting the results of cost-effectiveness studies

In developed nations, health care spending is an increasingly important economic and political issue. The discipline of cost-effectiveness (CE) analysis has developed over several decades as a tool for objectively assessing the value of new medical strategies, by simultaneously examining incremental health benefits in light of incremental costs. The underlying goal of CE research is to allow clinicians and policymakers to make more rational decisions regarding clinical care and resource allocation. This review will provide the reader with an understanding of the theoretical underpinnings of CE analysis, the types of analyses commonly performed and reported in the medical literature, some important strengths and weaknesses of different analytical approaches, and key principles in the interpretation of CE results. Key principles reviewed include the impact of analytic perspective, the importance of proper incremental comparisons, the effect of time horizon, and methods for exploring and describing uncertainty. Illustrative examples from the cardiology literature are discussed.

Cost of preimplantation cardiac imaging in patients referred for a primary-prevention implantable cardioverter-defibrillator

Recent guidelines have focused on ejection fraction cut-off values to determine eligibility for primary-prevention implantable cardioverter-defibrillators (ICDs). Clinical trials that led to the guidelines used varying techniques for ejection fraction assessment, including echocardiography and multigated acquisition (MUGA) scan. A prospective cohort study to determine the economic attractiveness of repeated echocardiography and MUGA scanning during the evaluation process of patients referred for consideration of a primary-prevention ICD was undertaken. From January 2005 to December 2006, data were collected for patients aged >18 years with ejection fraction <30% referred for a primary-prevention ICD based on referral assessment of heart function in any form. Costs based on the 2006 Ontario Health Insurance Plan fee schedule were determined for clinical assessment, echocardiography, MUGA scanning, and ICD implantation in patients who remained eligible based on MUGA ejection fraction. The 100 patients (age 61.1 +/- 10.2 years; 78 men) assessed for primary-prevention ICD implantation had an ejection fraction of 28.9 +/- 12.3% using MUGA scan. Thirty-one of 100 patients (31%) had an ejection fraction >30% and were no longer eligible for an ICD. Although imaging increased preimplantation cost from dollars 130 to dollars 536 per patient, averted inappropriate ICDs decreased the overall per-patient cost from dollars 20,914 to dollars 14,877. Despite an additional testing cost of dollars 40,599, the overall cost savings was dollars 603,722 in the 100 patients, with a cost savings of dollars 6,037 per patient. In conclusion, verification of ejection fraction identified a significant proportion of patients who were not eligible for an ICD.

Implantable device therapy

Sudden cardiac death (SCD) accounts for two-thirds of fatal events related to heart disease. Coronary heart disease and non-ischemic cardiomyopathy are the most common causes of SCD. Data from major randomized trials have consistently shown that therapy with an implantable cardioverter defibrillator (ICD) results in a significant and meaningful effect on survival through a reduction in the risk of SCD in these population. These data have resulted in a marked increase in the application of implantable device therapy in the past 2 decades from secondary prevention with an implantable cardioverter/defibrillator (ICD) in survivors of a cardiac arrest to primary prevention of SCD in asymptomatic patients with ischemic and non-ischemic left ventricular dysfunction, and prevention of symptomatic heart failure progression and death with cardiac resynchronization therapy (CRT), and devices that combine CRT and ICD therapies (CRT-D). However, there are still areas of uncertainty regarding device therapy that include inconsistent benefit in risk-subgroups of patients with low ejection fraction; increased risk of heart failure after life-prolonging ICD therapy, and a considerable rate of device malfunction despite increasing sophistication. In the present review we focus on current data regarding the clinical indications as well as the safety and efficacy of implantable device therapy, including ICD, CRT, and CRT-D.

Cost-effectiveness as an outcome in randomized clinical trials

BACKGROUND

Economic outcomes are now included in many contemporary randomized trials and provide an additional dimension to the assessment of interventions. Economic data collection and analysis pose several methodologic challenges, however.

PURPOSE

This paper reviews methods of incorporating economic outcomes in clinical trials.

RESULTS

Data on medical resource utilization and cost can readily be collected along with data on clinical outcomes. The cost of planned interventions can be measured with reasonable accuracy, but costs due to unplanned clinical events are more difficult to measure reliably. The total cost depends critically on these relatively infrequent, yet costly, adverse outcomes, which may partially, or even completely, offset any difference between the planned costs of the randomized therapies. Newer therapies are typically more expensive than older therapies, so the most important question is whether patient outcomes are improved sufficiently to justify the added expense. Cost-effectiveness analysis helps gauge the value provided by a new therapy. The cost-effectiveness of an intervention compared with an alternative is defined as the ratio of the incremental costs and the incremental clinical benefits, measured as dollars per quality-adjusted life-year added. The follow-up period in most clinical trials is generally long enough to measure the added cost of therapy, but may not capture the full benefits of treatment. The limited time horizon of clinical trials makes it necessary to use a model to extrapolate the observed effect of treatment and project the increase in life expectancy. The resulting cost-effectiveness ratio is sensitive to assumptions about the long-term efficacy of treatment, particularly whether the treatment effect will continue or dissipate over time.

CONCLUSION

Economic outcomes can be measured alongside clinical outcomes in randomized trial. While the use of cost-effectiveness models falls outside the strictly empirical, within-trial analysis framework that is embraced by most clinical trialists, it provides an explicit approach to assessing whether the intervention under study provides a clinically meaningful improvement in outcome that is worthwhile.

Use of implantable cardioverter defibrillators in Canadian and US survivors of out-of-hospital cardiac arrest

BACKGROUND

Cardiac arrest due to ventricular arrhythmia in the absence of a reversible cause or contraindication has been a class I indication for insertion of an implantable cardioverter defibrillator since 1998. We compared and contrasted the use of implantable cardioverter defibrillator therapy in Canada and the United States among adults who survived a cardiac arrest.

METHOD

Data on hospital separations from April 1, 1994 through March 31, 2003 were obtained from the Health Person-Oriented Information Database maintained by Statistics Canada and from the US National Hospital Discharge Survey on all patients with a primary diagnosis of cardiac arrest, ventricular fibrillation or ventricular flutter for the same 9-year period. We excluded all records of patients with a secondary diagnosis of acute myocardial infarction.

RESULTS

In Canada, 3793 patients survived to discharge after a cardiac arrest; 628 (16.6%) of these were implanted with a cardioverter defibrillator before discharge. The implant rate rose steadily from 5.4% in 1994/95 to 26.7% in 2002/03. In the United States, 23 688 (30.2%) of 78 538 such survivors received an implantable cardioverter defibrillator before discharge. Logistic regression analysis indicated that sex, age, fiscal year, the hospital's teaching status, hospital size and patient history of heart failure were positive predictors of implantable cardioverter defibrillator implantation. Age, renal failure, liver failure and cancer were negative predictors of receiving an implantable cardioverter defibrillator.

INTERPRETATION

The rate of use of implantable cardioverter defibrillator therapy for cardiac arrest survivors in Canada is increasing, but still is lower than the rate in the United States.

Clinical effectiveness and cost-effectiveness of implantable cardioverter defibrillators for arrhythmias: a systematic review and economic evaluation

OBJECTIVES

The clinical effectiveness and cost-effectiveness of implantable cardioverter defibrillators (ICD) for arrhythmias was assessed.

METHODS

A systematic review of the literature of systematic reviews and randomized controlled trials that reported mortality outcomes associated with implantable cardioverter defibrillators compared with antiarrhythmic drug therapy in people at risk of sudden cardiac death due to arrhythmias was undertaken. Economic evaluations were also sought. Inclusion criteria, data extraction, and quality assessment were undertaken by standard methodology. A decision analytic model was constructed using best available evidence to determine cost-effectiveness in a UK setting.

RESULTS

Eight randomized controlled trials, two systematic reviews, and a meta-analysis met the inclusion criteria and were of variable quality. Evidence suggests that ICDs reduce mortality in both secondary and primary prevention, although the magnitude of benefit depends on baseline risk for sudden cardiac death. Incremental cost per quality-adjusted life year ranged from 52,000 UK pounds ($98,000) to over 200,000 UK pounds ($379,000), depending on mortality risk and assumptions made.

CONCLUSIONS

Evidence suggests that ICDs reduce total mortality but may be cost-effective only in some subgroups of patients at high risk of ventricular arrhythmias. Further research is needed on risk stratification of patients in whom ICDs are most likely to be clinically and cost-effective.

Antiarrhythmic Therapy in Elderly Persons: A Device‐Based Approach

The management of ventricular arrhythmias in elderly persons has undergone a dramatic evolution over the past 10 years. Although life-threatening arrhythmias in elderly persons have been traditionally managed with a variety of pharmacologic agents, this population presents special challenges from pharmacokinetic and pharmacodynamic perspectives. Drug absorption, distribution, metabolism, and efficacy are often altered in elderly patients, resulting in a substantially narrowed therapeutic window. Nonpharmacologic therapy for ventricular arrhythmias has the advantage of not being subject to changes in metabolism, and due to recent technological advances in transvenous lead design as well as improved programming flexibility and reduction in device size, device-based therapy for malignant ventricular arrhythmias has become more attractive for use in elderly patients. Several recent studies have suggested that device-based therapy provides superior protection from malignant arrhythmias for both primary and secondary prevention indications. The majority of these studies suggest that the benefits of device-based therapy are conferred to patients independent of age. In addition, the complication rate of such therapy appears to be independent of age.