Evaluating the potential cost-effectiveness of stenting as a treatment for symptomatic single-vessel coronary disease. Use of a decision-analytic model

Bleeding risk in patients prescribed dual antiplatelet therapy and triple therapy after coronary interventions: the ADAPTT retrospective population-based cohort studies

Background

Bleeding among populations undergoing percutaneous coronary intervention or coronary artery bypass grafting and among conservatively managed patients with acute coronary syndrome exposed to different dual antiplatelet therapy and triple therapy (i.e. dual antiplatelet therapy plus an anticoagulant) has not been previously quantified.

Objectives

The objectives were to estimate hazard ratios for bleeding for different antiplatelet and triple therapy regimens, estimate resources and the associated costs of treating bleeding events, and to extend existing economic models of the cost-effectiveness of dual antiplatelet therapy.

Design

The study was designed as three retrospective population-based cohort studies emulating target randomised controlled trials.

Setting

The study was set in primary and secondary care in England from 2010 to 2017.

Participants

Participants were patients aged ≥ 18 years undergoing coronary artery bypass grafting or emergency percutaneous coronary intervention (for acute coronary syndrome), or conservatively managed patients with acute coronary syndrome.

Data sources

Data were sourced from linked Clinical Practice Research Datalink and Hospital Episode Statistics.

Interventions

Coronary artery bypass grafting and conservatively managed acute coronary syndrome: aspirin (reference) compared with aspirin and clopidogrel. Percutaneous coronary intervention: aspirin and clopidogrel (reference) compared with aspirin and prasugrel (ST elevation myocardial infarction only) or aspirin and ticagrelor.

Main outcome measures

Primary outcome: any bleeding events up to 12 months after the index event. Secondary outcomes: major or minor bleeding, all-cause and cardiovascular mortality, mortality from bleeding, myocardial infarction, stroke, additional coronary intervention and major adverse cardiovascular events.

Results

The incidence of any bleeding was 5% among coronary artery bypass graft patients, 10% among conservatively managed acute coronary syndrome patients and 9% among emergency percutaneous coronary intervention patients, compared with 18% among patients prescribed triple therapy. Among coronary artery bypass grafting and conservatively managed acute coronary syndrome patients, dual antiplatelet therapy, compared with aspirin, increased the hazards of any bleeding (coronary artery bypass grafting: hazard ratio 1.43, 95% confidence interval 1.21 to 1.69; conservatively-managed acute coronary syndrome: hazard ratio 1.72, 95% confidence interval 1.15 to 2.57) and major adverse cardiovascular events (coronary artery bypass grafting: hazard ratio 2.06, 95% confidence interval 1.23 to 3.46; conservatively-managed acute coronary syndrome: hazard ratio 1.57, 95% confidence interval 1.38 to 1.78). Among emergency percutaneous coronary intervention patients, dual antiplatelet therapy with ticagrelor, compared with dual antiplatelet therapy with clopidogrel, increased the hazard of any bleeding (hazard ratio 1.47, 95% confidence interval 1.19 to 1.82), but did not reduce the incidence of major adverse cardiovascular events (hazard ratio 1.06, 95% confidence interval 0.89 to 1.27). Among ST elevation myocardial infarction percutaneous coronary intervention patients, dual antiplatelet therapy with prasugrel, compared with dual antiplatelet therapy with clopidogrel, increased the hazard of any bleeding (hazard ratio 1.48, 95% confidence interval 1.02 to 2.12), but did not reduce the incidence of major adverse cardiovascular events (hazard ratio 1.10, 95% confidence interval 0.80 to 1.51). Health-care costs in the first year did not differ between dual antiplatelet therapy with clopidogrel and aspirin monotherapy among either coronary artery bypass grafting patients (mean difference £94, 95% confidence interval -£155 to £763) or conservatively managed acute coronary syndrome patients (mean difference £610, 95% confidence interval -£626 to £1516), but among emergency percutaneous coronary intervention patients were higher for those receiving dual antiplatelet therapy with ticagrelor than for those receiving dual antiplatelet therapy with clopidogrel, although for only patients on concurrent proton pump inhibitors (mean difference £1145, 95% confidence interval £269 to £2195).

Conclusions

This study suggests that more potent dual antiplatelet therapy may increase the risk of bleeding without reducing the incidence of major adverse cardiovascular events. These results should be carefully considered by clinicians and decision-makers alongside randomised controlled trial evidence when making recommendations about dual antiplatelet therapy.

Limitations

The estimates for bleeding and major adverse cardiovascular events may be biased from unmeasured confounding and the exclusion of an eligible subgroup of patients who could not be assigned an intervention. Because of these limitations, a formal cost-effectiveness analysis could not be conducted.

Future work

Future work should explore the feasibility of using other UK data sets of routinely collected data, less susceptible to bias, to estimate the benefit and harm of antiplatelet interventions.

Trial registration

This trial is registered as ISRCTN76607611.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 8. See the NIHR Journals Library website for further project information.

A systematic review of venoplasty versus stenting for the treatment of central vein obstruction in ipsilateral hemodialysis access

OBJECTIVE

This review examines the evidence regarding treatment of central vein obstruction (CVO) in the setting of ipsilateral hemodialysis access. The aim of this work is to identify whether long-term venous patency after central vein stenting is superior compared with balloon venoplasty. To date, there are no evidence-based guidelines to direct the management of CVO in the setting of ipsilateral hemodialysis access.

METHODS

An extensive systematic database search was performed using Medline, Embase, and the Cochrane Databases to identify all articles published from January 2000 to November 2019 comparing the management of CVO with venoplasty and/or stenting in the setting of ipsilateral hemodialysis access fistulae/grafts.

RESULTS

There were 655 patients with 456 stenoses and 208 occlusions who were treated; 288 underwent venoplasty and 345 underwent stenting. Twenty-two patients failed intervention owing to an inability to traverse the occlusion. The most affected vein was the brachiocephalic vein. A superior primary patency (PP) is noted in those treated with stenting compared with venoplasty in the first 2 years. Overall, both treatments are suboptimal demonstrating a 12-month PP rate of less than 60%. Assisted PP and secondary patency rates were similar for both venoplasty and stenting with a 12-month secondary patency rate of 77.8% to 91.6% for venoplasty and 89.6% to 98.4% for stenting. Periprocedural and long-term complications were rare for both interventions, occurring in 2% of patients.

CONCLUSIONS

Although both treatments demonstrated poor patency rates, greater PP is noted for stenting in the first 2 years. Coupled with low complication rates, this finding highlights a potential benefit of stenting as a first-line treatment for CVO. Allowing for the overall poor quality of current studies, even this short-term improvement in PP may benefit patients undergoing hemodialysis. Further research with randomised control trials as well as assessment of adjuvant techniques such as drug-coated stents and balloons, anticoagulant therapy, and the role of intravascular ultrasound use is required.

Early cost-utility analysis of tissue-engineered heart valves compared to bioprostheses in the aortic position in elderly patients

OBJECTIVES

Aortic valve disease is the most frequent indication for heart valve replacement with the highest prevalence in elderly. Tissue-engineered heart valves (TEHV) are foreseen to have important advantages over currently used bioprosthetic heart valve substitutes, most importantly reducing valve degeneration with subsequent reduction of re-intervention. We performed early Health Technology Assessment of hypothetical TEHV in elderly patients (≥ 70 years) requiring surgical (SAVR) or transcatheter aortic valve implantation (TAVI) to assess the potential of TEHV and to inform future development decisions.

METHODS

Using a patient-level simulation model, the potential cost-effectiveness of TEHV compared with bioprostheses was predicted from a societal perspective. Anticipated, but currently hypothetical improvements in performance of TEHV, divided in durability, thrombogenicity, and infection resistance, were explored in scenario analyses to estimate quality-adjusted life-year (QALY) gain, cost reduction, headroom, and budget impact.

RESULTS

Durability of TEHV had the highest impact on QALY gain and costs, followed by infection resistance. Improved TEHV performance (- 50% prosthetic valve-related events) resulted in lifetime QALY gains of 0.131 and 0.043, lifetime cost reductions of €639 and €368, translating to headrooms of €3255 and €2498 per hypothetical TEHV compared to SAVR and TAVI, respectively. National savings in the first decade after implementation varied between €2.8 and €11.2 million (SAVR) and €3.2-€12.8 million (TAVI) for TEHV substitution rates of 25-100%.

CONCLUSIONS

Despite the relatively short life expectancy of elderly patients undergoing SAVR/TAVI, hypothetical TEHV are predicted to be cost-effective compared to bioprostheses, commercially viable and result in national cost savings when biomedical engineers succeed in realising improved durability and/or infection resistance of TEHV.

Cost-effectiveness of CYP2C19-guided antiplatelet therapy in patients with acute coronary syndrome and percutaneous coronary intervention informed by real-world data

Current guidelines recommend dual antiplatelet therapy (DAPT) consisting of aspirin and a P2Y12 inhibitors following percutaneous coronary intervention (PCI). CYP2C19 genotype can guide DAPT selection, prescribing ticagrelor or prasugrel for loss-of-function (LOF) allele carriers (genotype-guided escalation). Cost-effectiveness analyses (CEA) are traditionally grounded in clinical trial data. We conduct a CEA using real-world data using a 1-year decision-analytic model comparing primary strategies: universal empiric clopidogrel (base case), universal ticagrelor, and genotype-guided escalation. We also explore secondary strategies commonly implemented in practice, wherein all patients are prescribed ticagrelor for 30 days post PCI. After 30 days, all patients are switched to clopidogrel irrespective of genotype (nonguided de-escalation) or to clopidogrel only if patients do not harbor an LOF allele (genotype-guided de-escalation). Compared with universal clopidogrel, both universal ticagrelor and genotype-guided escalation were superior with improvement in quality-adjusted life years (QALY's). Only genotype-guided escalation was cost-effective ($42,365/QALY) and demonstrated the highest probability of being cost-effective across conventional willingness-to-pay thresholds. In the secondary analysis, compared with the nonguided de-escalation strategy, although genotype-guided de-escalation and universal ticagrelor were more effective, with ICER of $188,680/QALY and $678,215/QALY, respectively, they were not cost-effective. CYP2C19 genotype-guided antiplatelet prescribing is cost-effective compared with either universal clopidogrel or universal ticagrelor using real-world implementation data. The secondary analysis suggests genotype-guided and nonguided de-escalation may be viable strategies, needing further evaluation.

Delay in reperfusion with transradial percutaneous coronary intervention for ST-elevation myocardial infarction: Might some delays be acceptable?

BACKGROUND

Randomized clinical trials (RCTs) suggest benefits for the transradial approach to percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). However, transradial PCI may delay reperfusion, leading to its avoidance. We sought to quantify the delay in reperfusion from transradial PCI ("transradial delay") that would need to be introduced to offset the potential mortality benefit of transradial PCI, compared with transfemoral, observed in RCTs.

METHODS

We developed a decision-analytic model to compare transfemoral and transradial PCI in STEMI. Thirty-day mortality rates were estimated by pooling STEMI patients from 2 RCTs comparing transfemoral and transradial PCI. We projected the impact of transradial delay using estimates of the increase in mortality associated with door-to-balloon time delays. Sensitivity analyses were performed to understand the impact of uncertainty in assumptions.

RESULTS

In the base case, a transradial delay of 83.0 minutes was needed to offset the mortality benefit of transradial PCI. When the mortality benefit of transradial PCI was one-quarter that observed in RCTs, the delay associated with equivalent mortality was 20.9 minutes. In probabilistic sensitivity analyses, transradial PCI was preferred over transfemoral PCI in 97.5% of simulations when transradial delay was 30 minutes and in 79.0% of simulations when delay was 60 minutes.

CONCLUSIONS

A substantial transradial delay is required to eliminate even a fraction of the mortality benefit observed with transradial PCI in RCTs. Results were robust to changing multiple assumptions and have implications for operators reluctant to transition to transradial PCI in STEMI because of concern for delaying reperfusion.

Medical therapy v. PCI in stable coronary artery disease: a cost-effectiveness analysis

BACKGROUND

Percutaneous coronary intervention (PCI) with either drug-eluting stents (DES) or bare metal stents (BMS) reduces angina and repeat procedures compared with optimal medical therapy alone. It remains unclear if these benefits are sufficient to offset their increased costs and small increase in adverse events.

OBJECTIVE

Cost utility analysis of initial medical therapy v. PCI with either BMS or DES.

DESIGN

. Markov cohort decision model. Data Sources. Propensity-matched observational data from Ontario, Canada, for baseline event rates. Effectiveness and utility data obtained from the published literature, with costs from the Ontario Case Costing Initiative.

TARGET POPULATION

Patients with stable coronary artery disease, confirmed after angiography, stratified by risk of restenosis based on diabetic status, lesion size, and lesion length. Time Horizon. Lifetime. Perspective. Ontario Ministry of Health and Long Term Care. Interventions. Optimal medical therapy, PCI with BMS or DES.

OUTCOME MEASURES

Lifetime costs, quality-adjusted life years (QALYs), and the incremental cost-effectiveness ratio (ICER).

RESULTS

of Base Case Analysis. In the overall population, medical therapy had the lowest lifetime costs at $22,952 v. $25,081 and $25,536 for BMS and DES, respectively. Medical therapy had a quality-adjusted life expectancy of 10.1 v. 10.26 QALYs for BMS, producing an ICER of $13,271/QALY. The DES strategy had a quality-adjusted life expectancy of only 10.20 QALYs and was dominated by the BMS strategy. This ranking was consistent in all groups stratified by restenosis risk, except diabetic patients with long lesions in small arteries, in whom DES was cost-effective compared with medical therapy (ICER of $18,826/QALY). Limitations. There is the possibility of residual unobserved confounding.

CONCLUSIONS

In patients with stable coronary artery disease, an initial BMS strategy is cost-effective.

Markov model for selection of aortic valve replacement versus transcatheter aortic valve implantation (without replacement) in high-risk patients

Comparisons between transcatheter aortic valve implantation without replacement (TAVI) and tissue aortic valve replacement (AVR) in clinical trials might not reflect the outcomes in standard clinical practice. This could have important implications for the relative cost-effectiveness of these alternatives for management of severe aortic stenosis in high-risk patients for whom surgery is an option. The mean and variance of risks, transition probabilities, utilities, and cost of TAVI, AVR, and medical management derived from observational studies were entered into a Markov model that examined the progression of patients between relevant health states. The outcomes and cost were derived from 10,000 simulations. Sensitivity analyses were based on variations in the likelihood of mortality, stroke, and other commonly observed outcomes. Both TAVI and AVR were cost-effective compared to medical management. In the reference case (age 80 years, the perioperative TAVI and AVR mortality was 6.9% vs 9.8%, and annual mortality was 21% vs 24%), the utility of TAVI was greater than that of AVR (1.78 vs 1.72 quality-adjusted life years) and the lifetime cost of TAVI exceeded that of AVR ($59,503 vs $56,339). The incremental cost-effectiveness ratio was $52,773/quality-adjusted life years. Threshold analyses showed that variation in the probabilities of perioperative and annual mortality after AVR and after TAVI and annual stroke after TAVI were important determinants of the favored strategy. Sensitivity analyses defined the thresholds at which TAVI or AVR was the preferred strategy with regard to health outcomes and cost. In conclusion, TAVI satisfies current metrics of cost-effectiveness relative to AVR and might provide net health benefits at acceptable cost for selected high-risk patients among whom AVR is the current procedure of choice.

Gemcitabine-releasing polymeric films for covered self-expandable metallic stent in treatment of gastrointestinal cancer

Non-vascular drug-eluting stents have been studied for the treatment of gastrointestinal cancer and cancer-related stenosis. In this study, we designed and evaluated a gemcitabine (GEM)-eluting covered nonvascular stent. Polyurethane (PU)/polytetrafluoroethylene (PTFE) film was selected for the drug loading and eluting membrane. The membrane was fabricated by dip-coating on a Teflon bar (∅; 10mm), air-dried, peeled off and applied to a self-expanding Nitinol stent. Various amounts of poloxamer 407 (PL, Lutrol F127, BASF) (8%, 10%, or 12% of PU by weight) were added to control the release of GEM from membranes. The membrane containing 12% PL (GEM-PU-PL12%) showed the most favourable release properties; 70% of the loaded GEM released within 35 days, including the 35% released during the initial burst. The biological activities of GEM-PU-PL12% were evaluated using human cholangiocarcinoma cells (SK-ChA-1). GEM-PU-PL12% most efficiently inhibited the proliferation of cholangiocarcinoma cells and most highly induced pro-inflammatory cytokines (TNF-α, IL-1β and IL-12) and p38 MAPKs in the cells. Subtumoural insertion of the GEM-PU-PL12% membrane more efficiently inhibited the growth of CT-26 colon cancer than other membranes. In this study, the GEM-eluting metal stents covered with PU-PL12% showed considerable feasibility for the treatment of malignant gastrointestinal cancer as well as cancer-related stenosis.

Transferability of health technology assessments and economic evaluations: a systematic review of approaches for assessment and application

Background:

Health technology assessments (HTA) generally, and economic evaluations (EE) more specifically, have become an integral part of health care decision making around the world. However, these assessments are time consuming and expensive to conduct. Evaluation resources are scarce and therefore priorities need to be set for these assessments and the ability to use information from one country or region in another (geographic transferability) is an increasingly important consideration.

Objectives:

To review the existing approaches, systems, and tools for assessing the geographic transferability potential or guiding the conduct of transferring HTAs and EEs.

Methods:

A systematic literature review was conducted of several databases, supplemented with web searching, hand searching of journals, and bibliographic searching of identified articles. Systems, tools, checklists, and flow charts to assess, evaluate, or guide the conduct of transferability of HTAs and EEs were identified.

Results:

Of 282 references identified, 27 articles were reviewed in full text and of these, seven proposed unique systems, tools, checklists, or flow charts specifically for geographic transferability. All of the seven articles identified a checklist of transferability factors to consider, and most articles identified a subset of ‘critical’ factors for assessing transferability potential. Most of these critical factors related to study quality, transparency of methods, the level of reporting of methods and results, and the applicability of the treatment comparators to the target country. Some authors proposed a sequenced flow chart type approach, while others proposed an assessment of critical criteria first, followed by an assessment of other noncritical factors. Finally some authors proposed a quantitative score or index to measure transferability potential.

Conclusion:

Despite a number of publications on the topic, the proposed approaches and the factors used for assessing geographic transferability potential have varied substantially across the papers reviewed. Most promising is the identification of an extensive checklist of critical and noncritical factors in determining transferability potential, which may form the basis for consensus of a future tool. Due to the complexities of identifying appropriate weights for each of the noncritical factors, it is still uncertain whether the assessment and calculation of an overall transferability score or index will be practical or useful for transferability considerations in the future.

Defining patients at high risk for gastrointestinal hemorrhage after drug-eluting stent placement: a cost utility analysis

INTRODUCTION

The study goal was to evaluate the cost-effectiveness of drug-eluting stent (DES) placement with consideration of gastrointestinal (GI) bleeding risk. DES reduce the need for future coronary revascularization, but require prolonged dual anti-platelet (DAT) therapy, which may increase the risk for GI bleeding. While DES have been found to be cost-effective in patients at average risk for GI bleeding, they may not be the most cost-effective strategy in higher risk patients.

METHODS

A Markov model was created to compare DES with bare metal stents (BMS). Patients were a hypothetical cohort of 60-year-old individuals with coronary artery stenosis that required nonemergent percutaneous coronary revascularization (PCI). The primary outcomes were the threshold incremental risks of GI bleeding from DAT based on willingness to pay (WTP) of $50,000, $100,000, and $150,000 per quality adjusted life year (QALY) gained.

RESULTS

For a WTP of $100,000, the relative risk of GI bleeding from DAT could be as high as 10.8 (when compared to aspirin alone) before DES would no longer be cost-effective. In patients with two risk factors for GI bleeding, the threshold relative risk could be as low as 1.6.

CONCLUSION

In average-risk patients, the risk of GI bleeding from DAT can be substantial without affecting the cost-effectiveness of DES. However, DES are unlikely to be cost-effective in patients with two or more risk factors for GI bleeding.

Cost analysis of sirolimus-eluting stents in the Japanese health insurance system

The cost-effectiveness of drug-eluting stents (DES) has been evaluated in the United States and Europe, however, there is little information from Japan. The present study evaluated the cost-effectiveness of sirolimus-eluting stents (SES) in Japan. In-hospital and follow-up costs of 25 consecutive patients undergoing SES implantation in a de novo lesion were evaluated. A control group for comparison was composed of 25 consecutive patients undergoing bare metal stent (BMS) implantation in a de novo lesion before the introduction of SES. There was no significant difference in resource use between the SES and BMS groups. Procedural cost (yen1,049,200 +/- 208,793 versus yen896,590 +/- 117,984, P = 0.01) was higher in the SES group than in the BMS group because of the higher reimbursement price of SES (yen378,000 versus yen258,000). In-hospital cost (yen1,202,891 +/- 208,793 versus yen1,050,280 +/- 177,984, P < 0.01) was higher in patients treated with SES. Less target lesion revascularization (4% versus 20%, P = 0.2) in patients with SES reduced the difference; aggregate 1-year cost was not significantly different (yen1,479,481 +/- 284,343 versus yen1,463,640 +/- 495,803, P = 0.9). It is concluded that SES may be cost-effective even in Japan.

Intense cardiac troponin surveillance for long-term benefits is cost-effective in patients undergoing open abdominal aortic surgery: a decision analysis model

BACKGROUND

Strategies to limit adverse cardiac events after vascular surgery continue to evolve. Early recognition and treatment of myocardial ischemia may be a key to improving postoperative survival rates. Cardiac troponin I (cTnI) screening is an effective means of surveillance for postoperative myocardial ischemic injury and has long-term prognostic value.

METHODS

We designed a Markov-based decision analysis model to determine the cost-effectiveness of routine surveillance with cTnI on postoperative Days 0, 1, 2, and 3, with an aim to institute tight heart rate control (60-65 bpm) with close monitoring and coronary care in the intensive care unit for 5 days in patients with cTnI >1.5 ng/mL. The key input variables obtained from published literature were as follows: probability of myocardial infarction, 0.049; cost of cTnI surveillance, $357; cost and efficacy of interventions, $13,145 and 0.55, respectively. The time horizon was lifetime and the target population being individuals aged 65 yr (median) undergoing elective open abdominal aortic surgery. The perspective for analysis was third-party payer.

RESULTS

The incremental cost-effectiveness ratio for cTnI surveillance was $12,641 per quality-adjusted life year compared with standard care without cTnI surveillance. During one-way sensitivity analysis, probability of myocardial infarction and efficacy of interventions were found to influence the cost-effectiveness. Multivariate sensitivity analysis with second-order Monte Carlo simulation revealed that cTnI surveillance was favored in 90.75% of simulations at a commonly used threshold of $50,000 per quality-adjusted life year.

CONCLUSIONS

In patients presenting for elective open abdominal aortic surgery, intensive surveillance with cTnI and early institution of aggressive beta-blockade is cost-effective.

A review of health care models for coronary heart disease interventions

This article reviews models for the treatment of coronary heart disease (CHD). Whereas most of the models described were developed to assess the cost effectiveness of different treatment strategies, other models have also been used to extrapolate clinical trials, for capacity and resource planning, or to predict the future population with heart disease. In this paper we investigate the use of modelling techniques in relation to different types of health intervention, and we discuss the assumptions and limitations of these approaches. Many of the models reviewed in this paper use decision tree models for acute or short term interventions, and Markov or state transition models for chronic or long term interventions. Discrete event simulation has, however, been used for more complex whole system models, and for modelling resource-constrained interventions and operational planning. Nearly all of the studies in our review used cohort-based models rather than population based models, and therefore few models could estimate the likely total costs and benefits for a population group. Most studies used de novo purpose built models consisting of only a small number of health states. Models of the whole disease system were less common. The model descriptions were often incomplete. We recommend that the reporting of model structure, assumptions and input parameters is more explicit, to reduce the risk of biased reporting and ensure greater confidence in the model results.

Cost effectiveness of paclitaxel-eluting stents for patients undergoing percutaneous coronary revascularization: results from the TAXUS-IV Trial

OBJECTIVES

This study sought to compare aggregate medical care costs for patients undergoing percutaneous coronary intervention with paclitaxel-eluting stents (PES) and bare-metal stents (BMS) and to formally evaluate the incremental cost effectiveness of PES for patients undergoing single-vessel percutaneous coronary intervention.

BACKGROUND

Although the cost effectiveness of SES has been studied in both clinical trials and decision-analytic models, few data exist on the cost effectiveness of alternative drug-eluting stent (DES) designs. In addition, no clinical trials have specifically examined the cost effectiveness of DES among patients managed without mandatory angiographic follow-up.

METHODS

We performed a prospective economic evaluation among 1,314 patients undergoing percutaneous coronary revascularization randomized to either PES (N = 662) or BMS (N = 652) in the TAXUS-IV trial. Clinical outcomes, resource use, and costs (from a societal perspective) were assessed prospectively for all patients over a 1-year follow-up period. Cost effectiveness was defined as the incremental cost per target vessel revascularization (TVR) event avoided and was analyzed separately among cohorts assigned to mandatory angiographic follow-up (n = 732) or clinical follow-up alone (n = 582).

RESULTS

The PES reduced TVR by 12.2 events per 100 patients treated, resulting in a 1-year cost difference of 572 dollars per patient with incremental cost-effectiveness ratios of 4,678 dollars per TVR avoided and 47,798 dollars/quality-adjusted life year (QALY) gained. Among patients assigned to clinical follow-up alone, the net 1-year cost difference was 97 dollars per patient with cost-effectiveness ratios of 760 dollars per TVR event avoided and $5,105/QALY gained.

CONCLUSIONS

In the TAXUS-IV trial, treatment with PES led to substantial reductions in the need for repeat revascularization while increasing 1-year costs only modestly. The cost-effectiveness ratio for PES in the study population compares reasonably with that for other treatments that reduce coronary restenosis, including alternative drug-eluting stent platforms.

An unadjusted NNT was a moderately good predictor of health benefit

BACKGROUND AND OBJECTIVE

Whether the number needed to treat (NNT) is sufficiently precise to use in clinical practice remains unclear. We compared unadjusted NNTs to quality-adjusted life years (QALYs) gained, a more comprehensive measures of health benefit.

STUDY DESIGN AND SETTING

From a subset (n = 65) of a dataset of 228 cost-effectiveness analyses, we compared how well NNTs predicted clinically important QALY gains using correlation analysis, multivariable models and receiver-operator curve (ROC) analysis.

RESULTS

NNT was inversely correlated with QALY gains (P < .001); this relationship was affected by quality of life and life-expectancy gains of treatment (P <or= .04). The NNT is a moderately accurate predictor of treatments that provide large health benefits (area under ROC 0.74-0.81). For ruling out therapies with low QALY gains (threshold <or=0.125 to <or=0.5 QALYs), an NNT >15 had a sensitivity of 82% to 100%. For ruling in therapies with high QALY gains (threshold >or=0.125 to >or=0.5 QALYs), an NNT <or=5 had a specificity of 77%.

CONCLUSION

Using NNT thresholds of <or=5 and >15 to rule in and out therapies with large QALY gains may provide general guidance regarding the magnitude of health benefit.

Biomedical and psychosocial predictors of anginal frequency in patients following angioplasty with and without coronary stenting

This study examined the contribution of biomedical and psychological variables in the report of anginal frequency at 6-week, 6- and 12-month follow-up in patients who received angioplasty with and without stent. Patients (N = 70) completed a battery of standardized questionnaries, including measures of depression, anxiety, and anger. Principal components analysis computed a single factor of negative emotion for use as a predictor in regression analyses. For the 6-week model, only baseline anginal frequency predicted anginal frequency. Negative emotion joined baseline anginal frequency in the prediction model for 6-month anginal frequency, and collectively accounted for 23% of the variance. For the 12-month model, baseline anginal frequency, female sex, and negative emotions remained in the model, accounting for 46% of the variance in anginal frequency. These results highlight the importance of biomedical and psychosocial variables in predicting anginal frequency with psychological variables sustaining predictive value over the course of recovery.

Economic impact of drug-eluting stents on hospital systems: a disease-state model

BACKGROUND

Drug-eluting intracoronary stents decrease restenosis and later revascularization. The US Department of Health and Human Services (HHS), recognizing the financial and clinical impact of this technology, recently proposed accelerated reimbursement to hospitals.

METHODS AND RESULTS

A disease state-transition computer model simulated the clinical and economic consequences to hospitals of drug-eluting stents over 5 years. Model parameters combined information from a longitudinal clinical database, a hospital cost-accounting system, and a survey instrument. Simulations were repeated 1000 times for each set of parameters. With 85% of stent procedures shifted to drug-eluting stents in the first year of availability, the mean number of repeat revascularizations dropped by 60.4% at year 5. With no changes in reimbursement policy, a hospital with a catheterization laboratory volume of 3112 patients yearly converted from a 2.01 million dollars (M) annual profit to an 8.10 M dollars loss in the first year (95% CI 8.09 M dollars to 8.12 M dollars) and 8.7 M dollars annual losses in later years. This represented an overall change in cash flow of 55.71 M dollars (95% CI 55.66 M dollars to 55.76 M dollars) away from the hospital over 5 years. The incremental reimbursement proposed by HHS reduced this loss to 4.75 M dollars in the first year and to 5.6 M dollars annually thereafter. In sensitivity analyses, the conversion of patients from bypass surgery to drug-eluting stents was the largest driver of overall cash flow shifts.

CONCLUSIONS

Although Medicare has proposed to increase reimbursement to ease the impact of drug-eluting stents on hospitals, this increase will not totally offset the costs.

Direct coronary stenting compared with stenting after predilatation is feasible, safe, and more cost-effective in selected patients: evidence to date indicating similar late outcomes

OBJECTIVES

To review the currently available data from studies assessing feasibility, safety, clinical outcome and cost-effectiveness of direct stenting.

BACKGROUND

With technical advances of stent designs and their delivery systems a new strategy has become increasingly popular: direct stent implantation without prior balloon dilatation.

METHODS

The Medline database was searched from January 1996 to March 2001 for clinical trials investigating direct stenting using the index terms direct stenting, coronary intervention, percutaneous transluminal coronary angioplasty (PTCA), PCI, angioplasty and ischemic heart disease. Studies were chosen based on the number of patients involved and endpoints mentioned. Data not yet published but presented at recent international meetings were also included. A comparison between direct stenting and stenting with predilatation was performed using for the latter results of the randomized trials supplemented with Benestent II data.

RESULTS

At least 26 studies have investigated direct stenting, showing high primary and final success rates with few complications. Direct stenting provides a way to reduce costs, shorten procedural and fluoroscopy times and lower material consumption. Immediate and long-term clinical outcomes appear to be similar to stenting with predilatation. Preliminary results of large randomized trials with angiographic follow-up indicate that restenosis rates are similar to those of conventional stenting strategies.

CONCLUSIONS

Direct stenting compared with stenting with predilatation is feasible, safe, faster and more cost-effective. The evidence to date shows similar late outcomes.

Cost-effectiveness of bypass surgery versus stenting in patients with multivessel coronary artery disease

PURPOSE

To compare the cost-effectiveness of surgical and angioplasty-based coronary artery revascularization techniques, in particular, angioplasty with primary stenting.

METHODS

We used data from the Study of Economics and Quality of Life, a substudy of the Bypass Angioplasty Revascularization Investigation (BARI), to measure the outcomes and costs of angioplasty and bypass surgery in patients with multivessel coronary artery disease who had not undergone prior coronary artery revascularization. Using a Markov decision model, we updated the outcomes and costs to reflect technology changes since the time of enrollment in BARI, and projected the lifetime costs and quality-adjusted life-years (QALYs) for the two procedures from the time of initial treatment through death. We accounted for the effects of improved procedural safety and efficiency, and prolonged therapeutic effects of both surgery and stenting. This study was conducted from a societal perspective.

RESULTS

Surgical revascularization was less costly and resulted in better outcomes than catheter-based intervention including stenting. It remained the preferred strategy after adjusting the stent outcomes to eliminate the costs and events associated with target lesion restenosis. Among angioplasty-based strategies, primary stent use cost an additional 189,000 US dollars per QALY gained compared with a strategy that reserved stent use for treatment of suboptimal balloon angioplasty results.

CONCLUSION

Bypass surgery results in better outcomes than angioplasty in patients with multivessel disease, and at a lower cost.

Impact of change in the price of percutaneous coronary intervention devices on medical expenses

Percutaneous coronary intervention (PCI) devices are much more expensive in Japan than in the United States, but their prices were reduced in April 2002. This study evaluated the impact of that change in the price of PCI devices on medical expenses. In-hospital costs of 22 consecutive patients who underwent elective single-vessel PCI without a debulking procedure before April 2002 were collected and the in-hospital cost of each patient was recalculated by applying the current prices of the PCI devices and those in the USA. For patients treated with PCI before April 2002, the in-hospital cost was 1,456,375+/-358,781 yen, but when the current price is used, the in-hospital cost is estimated to be 1,355,812 +/-313,237 yen (7% reduction). If the prices of the devices were reduced to those in USA, there would be a 53% reduction (689,417 +/-99,139 yen). Although the change in the price of PCI devices in April 2002 has reduced in-hospital costs, the devices are still much more expensive in Japan than in the USA. Further reduction of the price is required to make PCI more cost-effective.

Cost-effectiveness of measuring fractional flow reserve to guide coronary interventions

BACKGROUND

Most patients come to the catheterization laboratory without prior functional tests, which makes the cost-effective treatment of patients with intermediate coronary lesions a practical challenge.

METHODS

We developed a decision model to compare the long-term costs and benefits of 3 strategies for treating patients with an intermediate coronary lesion and no prior functional study: 1) deferring the decision for percutaneous coronary intervention (PCI) to obtain a nuclear stress imaging study (NUC strategy); 2) measuring fractional flow reserve (FFR) at the time of angiography to help guide the decision for PCI (FFR strategy); and 3) stenting all intermediate lesions (STENT strategy). On the basis of the literature, we estimated that 40% of intermediate lesions would produce ischemia, 70% of patients treated with PCI and 30% of patients treated medically would be free of angina after 4 years, and the quality-of-life adjustment for living with angina was 0.9 (1.0 = perfect health). We estimated the cost of FFR to be 761 dollars, the cost of nuclear stress imaging to be 1093 dollars, and the cost of medical treatment for angina to be 1775 dollars per year. The extra cost of splitting the angiogram and PCI as dictated by the NUC strategy was 3886 dollars by use of hospital cost-accounting data. Sensitivity and threshold analyses were performed to determine which variables affected our results.

RESULTS

The FFR strategy saved 1795 dollars per patient compared with the NUC strategy and 3830 dollars compared with the STENT strategy. Quality-adjusted life expectancy was similar among the 3 strategies (NUC-FFR = 0.8 quality-adjusted days, FFR-STENT = 6 quality-adjusted life days). Compared with the FFR strategy, the NUC strategy was expensive (>800,000 dollars per quality-adjusted life year gained). Both screening strategies were superior to (less cost, better outcomes) the STENT strategy. Sensitivity analysis indicated that the NUC strategy would only become attractive (<50,000 dollars/quality-adjusted life years compared with FFR) if the specificity of nuclear stress imaging was >25% better than FFR. Our results were not altered significantly by changing the other assumptions.

CONCLUSION

In patients with an intermediate coronary lesion and no prior functional study, measuring FFR to guide the decision to perform PCI may lead to significant cost savings compared with performing nuclear stress imaging or with simply stenting lesions in all patients.

Coronary stent implantation throughout technical evolution: immediate and follow-up results

Coronary stenting (stent implantation) has evolved over the last 5 years with changes in stent design, stent material and the implantation technique. The use of high-pressure balloon inflation (HP), intravascular ultrasound (IVUS) and appropriate antiplatelet therapy have contributed to the abolishment of the need for subsequent anticoagulation, allowing extended stent applications. We compared results in three groups of patients having stent implantation throughout the period of evolution: group A: no IVUS, no HP, with subsequent anticoagulation treatment (n 3 434); group B: no IVUS, yes HP, without subsequent anticoagulation treatment (n 3 192); and group C: yes IVUS, yes HP, without subsequent anticoagulation treatment (n 3 588). The primary success rates were comparable in all groups. There was a clear change in indications for stenting in groups B and C compared with group A (elective stenting: group A 3 32%; group B 3 66%; group C 3 69%; P < 0.0001), in reference vessel size (group A 3 3.22 3 0.37 mm; group B 3 2.92 3 0.56 mm; group C 3 2.98 3 0.57 mm; P < 0.0001), and for presence of type B2 and C lesions (group A 3 57%; group B 3 72%; group C 3 74%; P < 0.001). The complication rate significantly decreased in group C (group A 3 3.6%; group B 3 4.1%; group C 3 1.2%; P < 0.001) and the mean patient hospital stay decreased to 2 days in groups B and C due to the abolition of the need for anticoagulant treatment. The angiographic restenosis rate increased in groups B and C (group A 3 20%; group B 3 34%; group C 3 32%; P < 0.001). The need for a repeat procedure increased as stenting of more complex lesions and smaller vessels was attempted: target lesion revascularization (TLR) was performed in 16% of patients in group A (73/434), in 18% of group B (35/192) and in 22% of group C (129/588) (P 3 0.04 for A versus C). Major cardiac events (MACE) occurred in 142 patients in group A (33%), 60 patients in group B (31%) and in 181 patients in group C (30%). The evolving technique of coronary stenting has expanded the spectrum of indications and range of coronary vessels attempted, and decreased the complication rates and hospital stay. However, in less-favorable subsets, additional improvements are needed to affect the long-term outcome.

[Direct Stenting without Predilation: a Single-Center Experience with 1,000 Lesions]

INTRODUCTION

Direct stenting has been shown to save costs, procedural time, radiation, and contrast use. We analyze the results of direct stenting in daily practice.

MATERIAL AND METHODS

We retrospectively analyzed the interventions in the first 1,000 lesions that were treated with direct stenting at our center. Primary success, dissection, need for additional dilation, embolism, stent loss, and side branch occlusion were the variables assessed.

RESULTS

Direct stenting was attempted in 1,000 lesions in 784 patients (age 63 11 years, females 21%, diabetes 37%). Primary or rescue angioplasty was performed in 8%. One or more thrombi were found in 16%, bifurcation in 9%, calcification in 5%, angulation in 2.3%, and tortuosity in 3.2%. The reference diameter was 3.0 0.5 mm. The primary success rate was 93.1%. Failure of direct stenting (6.9%) was associated with the circumflex artery in 38%, calcification in 26%, angulation in 22%, and tortuosity in 31%. In 39 lesions, additional dilation with different balloons was required. Additional stenting was required for dissection in 40 lesions and secondary to incomplete coverage of the lesion in 27. Thrombus embolism occurred in 7 lesions, 6 of them with a previously visible thrombus and one in a vein graft. Stent embolisms occurred in 6 cases, 4 of which were retrieved. Four side branches became occluded, but 2 of them were recovered at the end of the procedure.

CONCLUSIONS

Direct stenting is a safe technique with low percentage of dissection, need for postdilation, thrombus embolism, and side br

A practical cost analysis of bivalirudin

Despite advances in percutaneous coronary intervention (PCI) techniques and adjunctive therapies, the risks of ischemic and bleeding complications with PCI remain significant. These complications are associated with significant morbidity and mortality, as well as substantially higher costs. Bivalirudin is the only antithrombotic agent that has been shown to reduce both ischemic and hemorrhagic complications associated with PCI. Cost models drawn from the results of three clinical trials of bivalirudin have estimated its potential impact on total medical costs. In addition, the number needed to treat to avoid a bleeding complication has been calculated based on patients shown to have a heightened risk of bleeding in the Bivalirudin Angioplasty Trial. In all models assessed, the use of bivalirudin offset most of its own cost through reductions in bleeding and ischemic complications.

Cost-effectiveness of cadaveric and living-donor liver transplantation

BACKGROUND

Cadaveric liver transplantation (5-year survival >80%) represents the standard of care for end-stage liver disease (ESLD). Because the demand for cadaveric organs exceeds their availability, living-donor liver transplantation has gained increasing acceptance. Our aim was to assess the marginal cost-effectiveness of cadaveric and living-donor orthotopic liver transplantation (OLT) in adults with ESLD.

METHODS

Using a Markov model, outcomes and costs of ESLD treated (1) conservatively, (2) with cadaveric OLT alone, and (3) with cadaveric OLT or living-donor OLT were computed. The model was validated with published data. The case-based scenario consisted of data on all 15 ESLD patients currently on our waiting list (3 women, 12 men; median age, 48 years [range, 33-59 years]) and on the outcome of all OLT performed for ESLD at our institution since 1995 (n=51; actuarial 5-year survival 93%). Living-donor OLT was allowed in 15% during the first year of listing; fulminant hepatic failure and hepatocellular carcinoma were excluded.

RESULTS

Cadaveric OLT gained on average 6.2 quality-adjusted life-years (QALYs) per patient compared with conservative treatment, living-donor OLT, an additional 1.3 QALYs compared with cadaveric OLT alone. Marginal cost-effectiveness of a program with cadaveric OLT alone and a program with cadaveric and living-donor OLT combined were similar (E 22,451 and E 23,530 per QALY gained). Results were sensitive to recipient age and postoperative survival rate.

CONCLUSIONS

Offering living-donor OLT in addition to cadaveric OLT improves survival at costs comparable to accepted therapies in medicine. Cadaveric OLT and living-donor OLT are cost-effective.

Angiographic classification of coronary dissections after plain old balloon angioplasty for prediction of regression at follow-up

Coronary dissection after plain old balloon angioplasty often shows regression during follow-up. This study sought to determine whether we can predict such phenomenon angiographically. We analyzed 64 patients with 71 type B-D coronary dissections determined by the National, Heart, Lung, and Blood Institute (NHLBI) criteria. Regression was considered present when minimal lumen diameter increased by more than 0.3 mm during follow-up. Dissections were divided into subgroups using the NHLBI criteria and our classification in which type a and b dissections were characterized by the width of a dissection lumen exceeding one quarter of the reference diameter with the outer edge of the dissection lumen within the boundary of reference in type a and beyond it in type b. In type c and type d dissections, the width of the dissection lumen was within one quarter of the reference with its outer edge within the boundary of reference in type c and beyond it in type d. Type e dissection had a protruding flap or spiral appearance. Regression was recognized in 23.9%. The distribution of dissection types was similar in the groups with and without regression by the NHLBI criteria, but type c dissection had regression more frequently than the other types of coronary dissections (p<0.001) using our classification.

An off-the-shelf help list: a comprehensive catalog of preference scores from published cost-utility analyses

PURPOSE

The Panel on Cost-Effectiveness in Health and Medicine recommends an organized collection of preference measure values for health states that can be used in costutility analyses (CUAs). The authors sought to construct a catalog of preference scores from published CUAs, organize the catalog by clinical categories, and identify methods of preference score assessment.

METHOD

The authors systematically searched Medline and other databases to identify original CUAs published through 1997. Information was abstracted on the health state descriptions, corresponding preference scores, method of preference score elicitation, and the source of the estimate.

RESULTS

Two hundred twenty-eight CUAs were appraised. The authors found 949 health states and corresponding preference scores. Most frequently, health states pertained to the circulatory system (21.7%), health states were valued by experts (35.8%), and values were derived through community-based preference scores (23.5%).

CONCLUSION

A catalog of preference scores for health states can be constructed. The catalog (http://www.hsph.harvard.edu/organizations/hcra/cuadatabase/ intro.html) may provide a useful reference tool for producers and consumers of CUAs but also underscores the methodologic variation and inconsistencies present in the field.

Long term outcome and cost-effectiveness of stenting versus balloon angioplasty for acute myocardial infarction

OBJECTIVE

To investigate the long term clinical outcome and cost-effectiveness of stenting compared with balloon angioplasty in patients with acute myocardial infarction.

METHODS

Patients with acute myocardial infarction were randomly allocated to primary stenting (112) or balloon angioplasty (115). The primary end point was the cumulative first event rate of death, non-fatal reinfarction, or target vessel revascularisation. Secondary end points were restenosis at six months and the cost-effectiveness at follow up.

RESULTS

After 24 months, the combined clinical end point of death/reinfarction was 4% after stenting and 11% after balloon angioplasty (p = 0.04). Subsequent target vessel revascularisation was necessary in 15 patients (13%) after stenting and in 39 (34%) after balloon angioplasty (p < 0.001). The cumulative cardiac event-free survival rate was also higher after stenting (84% v 62%, p < 0.001). The angiographic restenosis rate after stenting was less than after balloon angioplasty (12% v 34%, p < 0.001). Despite the higher initial costs of stenting (Dfl 21 484 v Dfl 18 625, p < 0.001), the cumulative costs at 24 months were comparable with those of balloon angioplasty (Dfl 31 423 v Dfl 32 933, p = 0.83).

CONCLUSIONS

Compared with balloon angioplasty, primary stenting for acute myocardial infarction results in a better long term clinical outcome without increased cost.

A pragmatic and cost-effective strategy of a combination therapy of interferon alpha-2b and ribavirin for the treatment of chronic hepatitis C

BACKGROUND

Combination of interferon (IFN) alpha and ribavirin is considered the standard treatment for patients with chronic hepatitis C. While combination therapy is more effective than IFN alone, the optimal management of combination treatment remains uncertain.

OBJECTIVE

To assess a pragmatic and cost-effective strategy for the therapy of treatment-naive patients with chronic hepatitis C.

DESIGN

Markov model on original data of two randomized trials.

METHODS

A validated computer simulation model was applied to non-cirrhotic hepatitis C virus (HCV)-infected patients. Patient characteristics and efficacy of treatment were extracted from two randomized trials reporting on 1,445 non-cirrhotic patients. Different strategies were compared separately for genotype 1 and genotype non-1 (mostly genotype 2/3) infections: (1) no treatment; (2) IFN for 48 weeks (if at 12 weeks HCV RNA undetectable); (3) IFN and ribavirin for 24 weeks; (4) IFN and ribavirin for 48 weeks; (5) IFN and ribavirin for 48 weeks (if at 24 weeks HCV RNA undetectable). All strategies were tested for different combinations of known response factors.

RESULTS

In genotype non-1 infection, 24 weeks of combination therapy dominates all other strategies. In genotype 1 infection, 48 weeks of combination therapy for week-24 responders only prolongs life expectancy at a favourable cost-effectiveness ratio (CE) of 7,135 euros per quality-adjusted life year (QALY). Taking response factors other than genotype into account does not add to the effectiveness or cost effectiveness.

CONCLUSION

Treating non-cirrhotic patients with chronic hepatitis C according to genotype only is most cost effective independent of the number of other known response factors.

Comparison of coronary-artery bypass surgery and stenting for the treatment of multivessel disease

BACKGROUND

The recent recognition that coronary-artery stenting has improved the short- and long-term outcomes of patients treated with angioplasty has made it necessary to reevaluate the relative benefits of bypass surgery and percutaneous interventions in patients with multivessel disease.

METHODS

A total of 1205 patients were randomly assigned to undergo stent implantation or bypass surgery when a cardiac surgeon and an interventional cardiologist agreed that the same extent of revascularization could be achieved by either technique. The primary clinical end point was freedom from major adverse cardiac and cerebrovascular events at one year. The costs of hospital resources used were also determined.

RESULTS

At one year, there was no significant difference between the two groups in terms of the rates of death, stroke, or myocardial infarction. Among patients who survived without a stroke or a myocardial infarction, 16.8 percent of those in the stenting group underwent a second revascularization, as compared with 3.5 percent of those in the surgery group. The rate of event-free survival at one year was 73.8 percent among the patients who received stents and 87.8 percent among those who underwent bypass surgery (P<0.001 by the log-rank test). The costs for the initial procedure were $4,212 less for patients assigned to stenting than for those assigned to bypass surgery, but this difference was reduced during follow-up because of the increased need for repeated revascularization; after one year, the net difference in favor of stenting was estimated to be $2,973 per patient.

CONCLUSION

As measured one year after the procedure, coronary stenting for multivessel disease is less expensive than bypass surgery and offers the same degree of protection against death, stroke, and myocardial infarction. However, stenting is associated with a greater need for repeated revascularization.

Chronic Coronary Occlusions

The goal of management of chronic coronary occlusions is primarily the relief of cardiac ischemic symptoms. This may be achieved through the use of medical therapy, recanalization by percutaneous endovascular intervention or coronary artery bypass grafting (CABG). Recanalization of the occluded vessel also may have the additional benefits of improved cardiac function and long-term survival.

Comparison of direct coronary stenting with and without balloon predilatation in patients with stable angina pectoris. BET (Benefit Evaluation of Direct Coronary Stenting) Study Group

The purpose of this study was to compare the effects of stent placement with and without balloon predilatation on duration of the procedure, reduction of procedure-related costs, and clinical outcomes. Although preliminary trials of direct coronary stenting have demonstrated promising results, the lack of randomized studies with long-term follow-up has limited the critical evaluation of the role of direct stenting in the treatment of obstructive coronary artery disease. Between January and September 1999, 338 patients were randomly assigned to either direct stent implantation (DS+; 173 patients) or standard stent implantation with balloon predilatation (DS-; 165 patients). Baseline clinical and angiographic characteristics were similar in the 2 groups. Procedural success was achieved in 98.3% of patients assigned to DS+ and 97.5% of patients assigned to DS- (p = NS), with a crossover rate of 13.9%. Compared with DS-, DS+ conferred a dramatic reduction in procedure-related cost ($956.4 +/- $352.2 vs $1,164.6 +/- $383.9, p <0.0001) and duration of the procedure (424.2 +/- 412.1 vs 634.5 +/- 390.1 seconds, p < 0.0001). At 6-month follow-up, the incidence of major adverse cardiac events including death, angina pectoris, myocardial infarction, congestive heart failure, repeat angioplasty, or coronary artery bypass graft surgery was 5.3% in DS+ and 11.4% in DS- (p = NS). Multivariate analysis demonstrated that major adverse cardiac events rates were related to stent length of 10 mm (relative risk [RR] 3.25, 95% confidence intervals [CI] 1.36 to 7.78; p = 0.008), stent diameter of 3 mm (RR 2.69, 95% CI 1.03 to 7.06; p = 0.043), and complex lesion type C (RR 2.83, 95% CI 1.02 to 7.85; p = 0.045). Thus, in selected patients, this prospective randomized study shows the feasibility of DS+ with reduction in procedural cost and length, and without an increase in in-hospital clinical events and major adverse cardiac events at 6-month follow-up.

The cost-effectiveness of repairing ruptured abdominal aortic aneurysms

BACKGROUND

Although advances in technology have reduced the operative risk of elective abdominal aortic aneurysm (AAA) repair, the surgical repair of ruptured AAAs is associated with a much poorer prognosis and a higher cost. Accordingly, it has been suggested that patients with predictably high rates of morbidity and mortality from ruptured AAA may not benefit from surgical intervention.

METHODS AND RESULTS

A cost-effectiveness analysis was performed with the use of a Markov decision-analytic model to compute long-term survival in quality-adjusted life years and lifetime costs for a hypothetical cohort of patients with ruptured AAAs managed with either a strategy of open surgical repair or no intervention. Probability estimates for the various outcomes were based on a review of the literature. Average costs of (1) the immediate hospitalization ($28,356) and (2) complications resulting from the procedure were based on the average use of resources as reported in the literature and from a hospital's cost accounting system. Our measure of outcome was the incremental cost-effectiveness ratio. For our base-case analysis, the repair of ruptured AAAs was cost-effective with an incremental cost-effectiveness ratio of $10,754. (Society is usually willing to pay for interventions with cost-effectiveness ratios of less than $60,000; for example, the costeffectiveness ratios for coronary artery bypass grafting and dialysis are $9500 and $54,400, respectively.) In sensitivity analyses, the cost-effectiveness of repairing ruptured AAAs was influenced only by alterations in the operative mortality. If the operative mortality exceeded 88%, repair of ruptured AAAs was no longer cost-effective. As an independent variable, increasing age had no substantial impact on the cost-effectiveness, although it is reported to be associated with increased operative mortality. It was necessary that the patient's cost of the initial hospitalization for ruptured AAA exceed $195,000 before repairing ruptured AAAs was no longer cost-effective.

CONCLUSIONS

Our analysis suggests that despite the high cost and poor outcomes, the surgical repair of ruptured AAAs is still cost-effective when compared with no intervention. The cost of repairing ruptured AAAs falls within society's acceptable limits and therefore should not be a consideration in the management of patients with AAAs.

Cost analysis between stent and conventional balloon angioplasty

The present study evaluated the cost of coronary stenting compared with conventional balloon angioplasty in Japan. Procedural cost was estimated as the sum of the procedural fee and the cost of devices such as angioplasty balloon and stent. The data such as the number of balloon catheters and stents used, and the rate of crossovers that was shown by the Stent Restenosis Study (STRESS) were applied to calculate the costs of stenting and conventional balloon angioplasty. For the estimation of hospital room and nursing costs, the length of the in-hospital stay was estimated at 7 days. The costs of procedures such as laboratory and radiological tests were determined based on routine coronary intervention at Chiba University Hospital. The rates of target lesion revascularization in the STRESS trial (conventional balloon angioplasty: 21%, stenting: 15%) were used to calculate the cost during follow up. The in-hospital costs of conventional balloon angioplasty and stenting were estimated to be Yens 982,300 and Yens 1,416,893, respectively. The overall costs, including follow-up cost, of conventional balloon angioplasty and stenting were estimated to be Yens 1,188,583 and Yens 1,564,238, respectively. The in-hospital cost of stenting is higher compared with conventional balloon angioplasty because of greater balloon use and direct stent cost. Lower target lesion revascularization reduces the cost difference between conventional balloon angioplasty and stenting, but the higher initial cost of stenting is not fully offset.

One-year clinical outcomes and relative costs of primary infarct artery stenting versus angioplasty following systemic thrombolysis for acute myocardial infarction

We investigated the clinical effectiveness and relative cost of two different infarct artery revascularization strategies in patients following systemic thrombolysis for acute myocardial infarction. The clinical efficacy and relative cost of stenting and angioplasty have not been investigated in patients requiring infarct artery revascularization after systemic thrombolysis for myocardial infarction. We prospectively enrolled 220 consecutive patients who received thrombolytic therapy for acute myocardial infarction and were subsequently treated with either angioplasty or primary stenting of the infarct artery. In-hospital and 1-year clinical outcomes, including death, myocardial infarction, and repeat revascularization, and total hospital costs over the 1-year study period were assessed. Compared to angioplasty, primary stenting resulted in lower in-hospital mortality (4% vs. 0%; P = 0.01) and reduced rates of repeat percutaneous or surgical revascularization (7% vs. 0%; P = 0.0009). At 1-year follow-up, stenting was associated with a lower death rate (6.25% vs. 0%; P = 0.002) and reduced repeat infarct artery revascularization (11% vs. 27%; P = 0. 001). Initial hospitalization costs were higher in the stent group ($11,818 +/- $3,377 vs. $9,723 +/- $8,661; P = 0.014) due primarily to catheterization laboratory-related expenditures ($7,346 +/- $2, 395 vs. $3,567 +/- $1,212; P = 0.0001). However, the cumulative 1-year medical cost difference between the two groups was not significant ($13,938 +/- $5,939 vs. $12,914 +/- $9,308; P = 0.33). Following thrombolytic therapy, primary infarct artery stenting reduced in-hospital and 1-year mortality and revascularization rates compared to angioplasty. Stenting was associated with higher initial hospital costs, which were off-set by lower revascularization rates, resulting in comparable total hospitalization costs after 1 year. These findings have important clinical and economic implications in an increasingly cost-conscious health care environment. Cathet. Cardiovasc. Intervent. 49:135-141, 2000.

Direct coronary stenting without predilation

OBJECTIVES

Coronary stenting is the primary therapeutic option for percutaneous treatment of many coronary lesions, after the risk of subacute stent thrombosis and bleeding complications has been reduced by improved antithrombotic regimens and high pressure stent expansion.

BACKGROUND

Direct stent implantation (without predilation) has been considered a promising new technique that may reduce the procedure time, radiation exposure time and cost.

METHODS

After having reviewed all cases of stent implantation from February to June 1998 (n = 585), 185 (32%) of these patients were retrospectively considered candidates for direct stent implantation without predilation, according to prespecified criteria (i.e., absence of severe coronary calcifications and/or tortuosity of the lesion or the segment proximal to the lesion). By operator preference, direct coronary stent implantation was actually attempted in 123 (21%) of the 585 patients (100 men, 60 +/- 10 years old) on 123 lesions. The impact of direct stenting in terms of cost, procedure time, radiation exposure time and amount of contrast dye used was assessed by comparing the two groups of patients who underwent single-vessel stenting without (n = 69) and with (n = 46) predilation.

RESULTS

Direct stenting was successful in 118 patients (96%). No acute or subacute complications occurred in these patients. Procedure time, radiation exposure time and cost were significantly lower in the group of patients who had single-vessel direct versus conventional stenting (45 +/- 31 vs. 64 +/- 46 min, 12 +/- 9 vs. 16 +/- 10 min and 1,305 +/- 363 vs. 2,210 +/- 803 Euro, respectively; p < 0.05 for all).

CONCLUSIONS

Direct stenting without predilation in selected lesions seems to be a safe and successful procedure that provides a way to contain cost and to shorten radiation exposure time.

The cost-effectiveness of endovascular repair versus open surgical repair of abdominal aortic aneurysms: A decision analysis model

PURPOSE

Endovascular repair (EVR) is a less-invasive method for the treatment of abdominal aortic aneurysms (AAAs) as compared with open surgical repair (OSR). The potential benefits of EVR include increased patient acceptance, less resource utilization, and cost savings. This study was designed to determine whether the EVR of AAAs is a cost-effective alternative to OSR.

METHODS

A cost-effectiveness analysis was performed using a Markov decision analysis model to compute long-term survival rates in quality-adjusted life years and lifetime costs for a hypothetical cohort of patients who underwent either OSR or EVR. Probability estimates of the different outcomes of the two alternative strategies were made on the basis of a review of the literature. The average costs of (1) the immediate hospitalization ($16,016 for OSR, $20,083 for EVR), (2) the complications that resulted from each procedure, (3) the subsequent interventions, and (4) the surveillance protocol were determined on the basis of average resource utilization as reported in the literature and from our hospital's cost accounting system. Our measure of outcome was the cost-effectiveness ratio.

RESULTS

For our base-case analysis (70-year-old men with 5-cm AAAs), EVR was cost-effective with a cost-effectiveness ratio of $22,826-society usually is willing to pay for interventions with cost-effectiveness ratios of less than $60,000 (eg, cost-effectiveness ratios for coronary artery bypass grafting and dialysis are $9500 and $54,400, respectively). This conclusion did not vary significantly with increases in procedural costs for EVR (ie, if the cost of the endograft increased from $8000 to $12,000, EVR remained cost-effective with a cost-effectiveness ratio of $32,881). The cost-effectiveness of EVR was critically dependent on EVR producing a large reduction in the combined mortality and long-term morbidity rate (stroke, dialysis-dependent renal failure, major amputation, myocardial infarction) as compared with OSR (ie, a reduction in the combined mortality and long-term morbidity rate of OSR from 9.1% to 4.7% made EVR no longer cost-effective).

CONCLUSION

Despite the high cost of new technology and the need for close postoperative surveillance, EVR is a cost-effective alternative for the repair of AAAs. However, the cost-effectiveness of this new technology is critically dependent on its potential to reduce morbidity and mortality rates as compared with OSR. EVR may not be cost-effective in medical centers where OSR can be performed with low risk.

Trends in clinical and economic outcomes of coronary angioplasty from 1992 to 1995: a population-based analysis

BACKGROUND

The impact of recent developments in coronary angioplasty on the broad spectrum of patients treated in routine practice is largely undefined. Analysis of population-based data can provide insight into trends in clinical outcomes and associated costs of coronary angioplasty procedures.

METHODS AND RESULTS

With the use of a comprehensive hospital discharge database covering more than 11 million Canadians, we analyzed 12,748 first-time angioplasty procedures performed from 1992 to 1995 inclusive. Patient demographics and major adverse events were recorded. With the use of forward linkage, readmissions within 12 months were classified according to procedure performed and/or most responsible diagnosis. The proportion of patients readmitted, the number of readmissions per index procedure, and diagnosis-specific readmission costs were compared by calendar year. Over the 4-year study period, there was a 21% increase in the annual volume of index procedures. There were no statistically significant differences between 1992 and 1995 in sex distribution, mean age, comorbid conditions, length of stay, or need for coronary bypass surgery related to the index procedure. The all-cause readmission rate declined from 51.6% to 47.2% between 1992 and 1995 (P <.001), primarily because of a decline in the admission rate for repeat revascularization from 24.8% to 19.6% (P <.001). The 12-month readmission cost declined by $435 (1994 Canadian dollars) per patient.

CONCLUSIONS

The clinical outcomes of coronary angioplasty in a broad cohort of patients have improved in recent years. Although readmissions within 1 year of an angioplasty procedure remain common, the number related to repeat revascularization has declined, with an associated decline in downstream costs.

The high cost of syncope: cost implications of a new insertable loop recorder in the investigation of recurrent syncope

BACKGROUND

Patients with recurrent syncope frequently undergo extensive investigations that consume significant health care resources. Recent advances in long-term monitoring techniques have enhanced diagnostic yield in patients with infrequent symptoms. There is little information on the relative cost-effective profile of the investigative tools used in patients with syncope.

METHODS

Two methods to determine health care costs in patients with syncope were used. In the first, health care resource utilization was determined in 24 patients with recurrent unexplained syncope and negative investigations who underwent insertion of the implantable loop recorder (ILR) during a pilot study of the feasibility of the device. The costs of investigations before, during, and after ILR implantation in each patient were calculated on the basis of median charges for an index investigation and a regression analysis of 1018 US Medicare hospital claims for syncope from 1993. Charges were converted to costs using a cost-to-charge ratio of 0.64. The second method was based on estimated costs per diagnosis and published diagnostic yields of 6 commonly applied tests in patients with syncope. A cohort simulation using theoretic models of 100 patients undergoing investigation for syncope was created to compare the diagnostic yield and cost per diagnosis of various diagnostic cascades.

RESULTS

In the pilot study, the cost of investigation of syncope in the 2 years before ILR insertion was $7584 per patient. After the ILR was inserted, a diagnosis was obtained in 21 of 24 patients (diagnostic yield 88%). The cost of therapy was $2452, followed by a reduction in cost of care to $596 over 30 +/- 10 months of follow-up. In the second method, the diagnostic yield of individual tests ranged from 3% for echocardiography to 88% for the ILR. The cost per diagnosis obtained ranged from $529 for the external loop recorder to $73,260 for electrophysiologic testing in patients without structural heart disease. An approach to syncope similar to that of the ILR pilot study resulted in a cost per diagnosis of $3193 and a diagnostic yield of 98%. Performance of echocardiography in half of the patients and electrophysiologic testing only in the presence of structural heart disease reduced the cost to $2494 and retained a diagnostic yield of 98%.

CONCLUSIONS

The cost of investigation of syncope is high. The ILR may reduce health care resource utilization by providing a diagnosis permitting definitive therapy. The cost per diagnosis profile of current diagnostic tests commonly used in patients with syncope is highly variable. A cost-effective approach to diagnosing this disorder can retain a high diagnostic yield with a reduction in resource utilization compared with a conventional approach.

Acute and long-term cost implications of coronary stenting

OBJECTIVES

We compared the acute and one year medical costs and outcomes of coronary stenting with those for balloon angioplasty (percutaneous transluminal coronary angioplasty) in contemporary clinical practice.

BACKGROUND

While coronary stent implantation reduces the need for repeat revascularization, it has been associated with significantly higher acute costs compared with coronary angioplasty.

METHODS

We studied patients treated at Duke University between September 1995 and June 1996 who received either coronary stent (n = 384) or coronary angioplasty (n = 159) and met eligibility criteria. Detailed cost data were collected initially and up to one year following the procedure. Our primary analyses compared six and 12 month cumulative costs for coronary angioplasty- and stent-treated cohorts. We also compared treatment costs after excluding nontarget vessel interventions; after limiting analysis to those without prior revascularization; and after risk-adjusting cumulative cost estimates.

RESULTS

Baseline clinical characteristics were generally similar between the two treatment groups. The mean in-hospital cost for stent patients was $3,268 higher than for those receiving coronary angioplasty ($14,802 vs. $11,534, p < 0.001). However, stent patients were less likely to be rehospitalized (22% vs. 34%, p = 0.002) or to undergo repeat revascularization (9% vs. 26%, p = 0.001) than coronary angioplasty patients within six months of the procedure. As such, mean cumulative costs at 6 months ($19,598 vs. $19,820, p = 0.18) and one year ($22,140 vs. $22,571, p = 0.26) were similar for the two treatments. Adjusting for baseline predictors of cost and selectively examining target vessel revascularization, or those without prior coronary intervention yielded similar conclusions.

CONCLUSIONS

In contemporary practice, coronary stenting provides equivalent or better one-year patient outcomes without increasing cumulative health care costs.