Cardioverter-defibrillators after MADIT-II: the balance between weight of evidence and treatment costs

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.

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.

Frequent Home Monitoring of ICD Is Effective to Prevent Inappropriate Defibrillator Shock Delivery

Recently, in the context of telemedicine, telemonitoring services are gaining attention. They are offered, for example, to patients with implantable cardioverter defibrillators (ICDs). A major problem associated with ICD therapy is the occurrence of inappropriate shocks which impair patients' quality of life and may also be arrhythmogenic. The telemonitoring can provide a valid support to intensify followup visits, in order to improve the prevention of inappropriate defibrillator shock, thus enhancing patient safety. Inappropriate shock generally depends on atrial fibrillation, supraventricular tachycardia, and abnormal sensing (such as those caused by electromagnetic interferences). As a practical example, an unusual case of an ICD patient who risked an inappropriate shock while taking a shower is reported. Continuous remote telemonitoring was able to timely warn cardiologist via GSM-SMS, who were able to detect improper sensing examining the intracardiac electrogram via Web. Patient was promptly contacted and warned to not further come in contact with the hydraulic system and any electrical appliance to prevent an inappropriate defibrillator shock. This demonstrates the effectiveness and usefulness of continuous remote telemonitoring in supporting ICD patients.

Cost-effectiveness of implantable cardioverter-defibrillator in today's world

The implantable cardioverter-defibrillator (ICD) is an example of an effective intervention with high up-front costs and delayed benefits. It has become a proven and well-accepted therapy not only for secondary but also for primary prevention of sudden cardiac death in patients with ischemic and non-ischemic heart disease. In recent years, the international guidelines have extended the indications to the prophylactic ICD, increasing the number of eligible patients and, together, the financial challenges of a widespread implementation. In this article, we review the available economic tools that can help address the ICD cost issue. We think that the awareness of such knowledge may facilitate dialogues between physicians, administrators and policy-makers, and help foster rational decision making.

Cost-effectiveness of implantable cardioverter-defibrillators in Brazil: primary prevention analysis in the public sector

BACKGROUND

Several studies have demonstrated the effectiveness and cost-effectiveness of implantable cardioverter-defibrillators (ICDs) in chronic heart failure (CHF) patients. Despite its widespread use in developing countries, limited data exist on its cost-effectiveness in these settings.

OBJECTIVE

To evaluate the cost-effectiveness of ICD in CHF patients under the perspective of the Brazilian Public Healthcare System (PHS).

METHODS

We developed a Markov model to evaluate the incremental cost-effectiveness ratio (ICER) of ICD compared with conventional therapy in patients with CHF and New York Heart Association class II and III. Effectiveness was evaluated in quality-adjusted life years (QALYs) and time horizon was 20 years. We searched MEDLINE for clinical trials and cohort studies to estimate data from effectiveness, complications, mortality, and utilities. Costs from the PHS were retrieved from national administrative databases. The model's robustness was assessed through Monte Carlo simulation and one-way sensitivity analysis. Costs were expressed as international dollars, applying the purchasing power parity conversion rate (PPP US$).

RESULTS

ICD therapy was more costly and more effective, with incremental cost-effectiveness estimates of PPP US$ 50,345/QALY. Results were more sensitive to costs related to the device, generator replacement frequency and ICD effectiveness. In a simulation resembling the MADIT-I population survival and ICD benefit, the ICER was PPP US$ 17,494/QALY and PPP US$ 15,394/life years.

CONCLUSIONS

In a Brazilian scenario, where ICD cost is proportionally more elevated than in developed countries, ICD therapy was associated with a high cost-effectiveness ratio. The results were more favorable for a patient subgroup at increased risk of sudden death.

Is cardiac resynchronization therapy cost-effective?

Cardiac resynchronization therapy (CRT) is a treatment of proven efficacy for selected patients with heart failure and associated conduction disturbances. The increasing financial burden that healthcare systems face has increased the interest in cost-effectiveness and cost-utility estimates, focused on devices with defibrillation capabilities (CRT-D), with a high upfront cost, as well as on simpler devices providing only biventricular pacing (CRT-P). Available economic estimates are largely dependent on data source, assumptions, modelling technique, time horizon, and perspective, leading to some variability in cost-effectiveness and cost-utility estimates. As a whole, cost-effectiveness and cost-utility estimates of both CRT-P and CRT-D improve as the time horizon examined is lengthened and appear to be below US$50,000 per quality-adjusted life-year, a threshold value commonly adopted for coverage of healthcare interventions in the USA and quite comparable with similar thresholds used within Europe. Limited data are available on the comparative cost-effectiveness or cost-utility of CRT-P and CRT-D devices. Moreover, more data on the effectiveness and long-term benefits of CRT-D and CRT-P are needed in order to estimate better the value of these treatments in the 'real world, as well as for attempts to improve cost-effectiveness through improved patient selection.

Trial-generated profiles for implantation of electrical devices in outpatients with heart failure: real-world prevalence and 1-year outcome

BACKGROUND

Randomized controlled trials have generated strong evidence on the efficacy of electrical device therapy in selected patients with heart failure (HF). The enrolment criteria of these three trials generated patient profiles that helped to shape current guidelines on chronic heart failure (CHF) treatment and sudden cardiac death (SCD) prevention. We investigated the prevalence of trial-generated profiles for implantable defibrillator or cardiac resynchronization therapy candidacy among HF outpatients; we explored differences between real-world and trial populations and we evaluated 1-year survival without device treatment.

METHODS

We reviewed Italian Network on Congestive Heart Failure (IN-CHF) registry patients (n = 4977) enrolled in a period (1995-2000) roughly concurrent with the MADIT-II and SCD-HeFT trials.

RESULTS

Regarding device eligibility, 14.5% IN-CHF patients at entry satisfied MADIT-II criteria, 6.8% satisfied CARE-HF criteria and as many as 47.9% fulfilled SCD-HeFT criteria. One-year overall mortality among non-implanted patients was 1.5 to 2-fold higher in each of these subgroups than in control arms of the corresponding trials. Among registry patients, different trial-profile combinations were associated with a wide range of 1-year outcomes (mortality, 8-35%; SCD/total mortality ratio, 0.35-0.57). Despite clear differences between registry and trial patients in pharmacological therapy (and clinical characteristics), none of the main drug classes independently predicted 1-year mortality in any of the IN-CHF subgroups.

CONCLUSIONS

As many as half the IN-CHF outpatients fulfilled current criteria for device implantation. Various subgroups had higher 1-year mortality than patients in trial control arms - a finding that may not be entirely attributable to differences in drug therapy (especially beta blockers).

Expenditure and value for money: the challenge of implantable cardioverter defibrillators

Many technology-driven interventions entail considerable financial cost, raising affordability issues. The implantable cardioverter defibrillator (ICD) is a case of an effective primary prevention intervention with high initial costs that is capable of delivering long-term population benefits. At first glance, such interventions may provoke diffidence, if not active resistance, due to the financial burdens which inevitably accompany their widespread adoption. In this article, we review the available economic tools that can help address the ICD cost issue. We think awareness of such knowledge may facilitate dialogues between physicians, administrators and policymakers, and help foster rational decision-making.

Telecardiology and remote monitoring of implanted electrical devices: the potential for fresh clinical care perspectives

Telecardiology may help confront the growing burden of monitoring the reliability of implantable defibrillators/pacemakers. Herein, we suggest that the evolving capabilities of implanted devices to monitor patients' status (heart rhythm, fluid overload, right ventricular pressure, oximetry, etc.) may imply a shift from strictly device-centered follow-up to perspectives centered on the patient (and patient-device interactions). Such approaches could provide improvements in health care delivery and clinical outcomes, especially in the field of heart failure. Major professional, policy, and ethical issues will have to be overcome to enable real-world implementation. This challenge may be relevant for the evolution of our health care systems.

Outcome of cardioverter-defibrillator implant in patients with arrhythmogenic right ventricular cardiomyopathy

The aim of the present study was to investigate outcomes of implantable cardioverter-defibrillator (ICD) treatment in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). We reviewed baseline/follow-up data of 15 consecutive ARVC patients (mean age 55 +/- 15 years) and 30 randomly drawn patients with coronary artery disease (CAD) (mean age 60 +/- 10 years) with matching durations of follow-up (all implanted with ICDs for primary/secondary prevention of sudden death). At implant, appropriate placement of the RV lead was more difficult in ARVC patients. During follow-up (median 41 months), appropriate interventions for any ventricular tachyarrhythmias occurred in 8 (53%) ARVC patients and 17 (57%) CAD patients, but the occurrence of high rate (>240 beats/min) ventricular tachyarrhythmias was higher in ARVC patients. Inappropriate ICD interventions occurred in 5 (33%) ARVC patients and 10 (33%) CAD patients. Lead-related adverse events requiring surgical revision occurred in 7 (47%) ARVC patients as compared with 4 (13%) CAD patients (P = 0.0004). While ICD implantation is highly effective for prevention of sudden death in ARVC, it does carry elevated burdens of long-term lead-related adverse events. These findings underline the need of careful follow-up in ARVC aimed at early recognition of complications that can impair ICD function.

Cardiac resynchronization therapy in clinical practice: need for electrical, mechanical, clinical and logistic synchronization

Considering the relatively short history of cardiac resynchronization therapy (CRT), the amount of available evidence of efficacy is impressive, and effectiveness studies are now required. Transfer of our experimentally gained knowledge into the real world raises issues that call for synchronization among the many specialists involved in chronic heart failure (CHF) management and CRT decision making. From an economic perspective, the demonstrated ability of CRT to reduce hospitalizations could help ease the burden on health systems derived from the growing incidence of CHF. Recent American College of Cardiology/American Heart Association guideline revisions should encourage a synchronized approach to rational deployment of CRT in selected patients. Nevertheless, current QRS criteria for CRT candidacy do not directly address the key issue of identification of patients with a pacing-correctable mechanical dyssynchrony (and in clinical trials, 25-30% of implanted patients did not respond to CRT). Echocardiography could become an important adjunct (or even an alternative) to QRS duration for patient selection; routine implementation would require use of straightforward, reproducible measurements, possibly obtainable on standard equipment. Echocardiography could also help optimize site location, although this would not eliminate lead placement problems. A series of issues remain open for investigation, including the potential of CRT in patients with atrial fibrillation, impact of devices with defibrillation ability, effects of electrical/pharmacological tailoring, need for confirmation that efficacy of CRT extends into the long term and possible use of CRT in mild CHF. Interdisciplinary synchronization in the various phases of CRT (screening, proposing, implementing, optimizing and monitoring) should eventually help develop a coordinated system for patient referral.

Primary Prevention of Sudden Cardiac Death: Can We Afford the Cost of Cardioverter-Defibrillators? Data from the Search-MI Registry-Italian Sub-study

BACKGROUND

Large randomized trials show that in appropriately selected patients with left ventricular dysfunction, implantable cardioverter-defibrillators (ICDs) can improve overall survival at 2-5 years. Since direct implementation of the criteria used in the MADIT II and SCD-HeFT will lead to a marked rise in ICD implants, there is a growing fear that increased use of ICDs may cause a dramatic burden to health care systems. The ICD has traditionally been seen as an expensive form of treatment, which is difficult to accept at the first look. This is mainly due to the nonlinear character of the ICD investment, characterized by high initial expenditure, followed by a deferred pay-off in terms of clinical benefits. Cost-effectiveness analysis may help provide a different perspective on the problem of ICD cost, as may estimation of the daily cost of ICD treatment, assuming a time horizon of 5-7 years--a particularly interesting subject for further registry studies.

METHODS AND RESULTS

Based on real expenditure data from 2002 to 2005, as recorded in the Search-MI Registry-Italian Sub-study of patients implanted on MADIT II indications, we estimated the daily costs associated with the device and leads. Over a 5-7 year time horizon, the average daily cost was estimated to be euro 4.60-euro 6.70. Translation of these figures into U.S. market conditions suggests a daily cost of around $7.90-$11.40.

CONCLUSIONS

These findings appear useful to help evaluate the affordability of ICD in comparison with other therapeutic options in a context of limited available economic resources.

Relevance of cardioverter defibrillators for the prevention of sudden cardiac death on the timing of heart transplantation

Information on the incidence of decompensation of chronic heart failure (CHF) in heart transplantation (HT) candidates eligible for prophylactic implantable cardioverter defibrillators (ICD) could provide insights into the influence of ICD on the timing for HT.

METHODS

We investigated the prevalence of candidates satisfying SCD-HeFT and MADIT-II criteria for prophylactic ICD among patients (n = 317) with CHF referred to our tertiary center for HT. In addition to standard clinical and laboratory assessments, baseline evaluation included two-dimensional standard transthoracic echocardiogram and 12-lead electrocardiogram.

RESULTS

At baseline, 19% of patients (n = 60) satisfied MADIT II criteria, and 58% (n = 185) fulfilled SCD-HeFT criteria. A total of 60% patients (n = 190) were eligible for prophylactic ICD implantation according to at least one set of criteria. Five-yr CHF decompensation-free survival was 68 +/- 4% in patients eligible for prophylactic ICD (p = 0.003), (RR 2.5, 95% CI 1.35-4.63).

CONCLUSIONS

SCD-HeFT could imply a threefold rise in ICD eligibility in tertiary settings. As ICD-eligible patients would likely remain at high risk of progressive ventricular dysfunction, strict follow-up should be considered extremely important to allow a timely referral for HT.

Weight of evidence: a review of concept and methods

"Weight of evidence" (WOE) is a common term in the published scientific and policy-making literature, most often seen in the context of risk assessment (RA). Its definition, however, is unclear. A systematic review of the scientific literature was undertaken to characterize the concept. For the years 1994 through 2004, PubMed was searched for publications in which "weight of evidence" appeared in the abstract and/or title. Of the 276 papers that met these criteria, 92 were selected for review: 71 papers published in 2003 and 2004 (WOE appeared in abstract/title) and 21 from 1994 through 2002 (WOE appeared in title). WOE has three characteristic uses in this literature: (1) metaphorical, where WOE refers to a collection of studies or to an unspecified methodological approach; (2) methodological, where WOE points to established interpretative methodologies (e.g., systematic narrative review, meta-analysis, causal criteria, and/or quality criteria for toxicological studies) or where WOE means that "all" rather than some subset of the evidence is examined, or rarely, where WOE points to methods using quantitative weights for evidence; and (3) theoretical, where WOE serves as a label for a conceptual framework. Several problems are identified: the frequent lack of definition of the term "weight of evidence," multiple uses of the term and a lack of consensus about its meaning, and the many different kinds of weights, both qualitative and quantitative, which can be used in RA. A practical recommendation emerges: the WOE concept and its associated methods should be fully described when used. A research agenda should examine the advantages of quantitative versus qualitative weighting schemes, how best to improve existing methods, and how best to combine those methods (e.g., epidemiology's causal criteria with toxicology's quality criteria).

Implications of cardiac resynchronization therapy and prophylactic defibrillator implantation among patients eligible for heart transplantation

This study analyzed the relations and time-related changes in eligibility for cardiac resynchronization therapy and prophylactic defibrillator implantation in 161 potential candidates for heart transplantation. Although up to 62% of patients who fulfilled the severity criteria for heart transplantation were eligible for either device, this percentage increased as clinical/instrumental parameters of heart failure severity worsened.