A cost-effectiveness model for coronary thrombolysis/reperfusion therapy

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 thrombolytics: a simplified model

OBJECTIVE OF THE STUDY

To construct a simple model for an internal, retrospective cost-effectiveness analysis and to calculate the incremental cost-effectiveness of tissue plasminogen activator (TPA) over streptokinase (SK) in Turkey.

SETTING

Koşuyolu Heart, Education and Research Hospital, Istanbul, Turkey.

METHOD

Among patients who were hospitalized for treatment of acute myocardial infarction (AMI), 196 were randomly selected. One-year mortality rates according to the treatment groups (TPA, SK, other) were determined. Among surviving patients, 28 from TPA and another 28 from SK group were randomly selected for the pharmacoeconomic analysis. Patient treatment data were taken from medical records while data regarding to costs were taken from hospital bills.

MAIN OUTCOME MEASURES

Incremental cost-effectiveness ratio (ICER). The cost part of the ratio was considered as 'the overall-costs', while the effectiveness part was considered as 'lives saved' per treatment group.

RESULTS

With an increased one-year survival rate of 2.37% and an increased cost of euro 1120.8 ($1165.6) per patient in the TPA group, the ICER for the use of TPA instead of SK was euro 47,289 ($49,180.6) per life saved.

CONCLUSION

This model can be a guide for similar analyses. The results of our study (the incremental cost-effectiveness of TPA over SK) will be informative for the decision-makers in Turkey, by whom the medical benefit for money spent would be assessed and judged. We believe that our results make a contribution to similar studies in the literature.

Prehospital delay time in acute myocardial infarction: an exploratory study on relation to hospital outcomes and cost

BACKGROUND

Short prehospital delay is associated with improved outcomes in myocardial infarction, but the impact on cost has not been tested. Shortening delay time could reduce health care expenditures.

METHODS AND RESULTS

Two hundred ninety-eight patients were examined with the use of a historic prospective design at 2 hospital sites. A secondary analysis was performed that used patients with confirmed myocardial infarction from the National Register of Myocardial Infarction and direct and indirect costs from the accounting system at the hospitals. Chi-square, Mann Whitney U, and Fisher exact tests were used for comparisons. Delay and 4 sets of variables were regressed on cost with the significant predictors used to construct a final model. The mean age was 71 +/- 14 years old; 62% were men. There were no major differences in demographics, cardiac history, risk factors, and admission characteristics between short and long delayers. Resource utilization and clinical outcomes were similar between the 2 groups; there was no difference in cost. Additional diagnostic procedures (odds ratio 2.92; 95% confidence interval 1.65-5.15) and complications (odds ratio 3.43; 95% confidence interval 2.03-5.82) were significant predictors of cost. Delay was not a predictor of high cost.

CONCLUSIONS

Short prehospital delay was not associated with improved clinical outcomes, nor did it predict cost. Explanations include (1) the low utilization of early reperfusion therapy in the short delay group, (2) the study lacked sufficient power to detect a difference in cost between short and long delayers, and (3) the severity of illness could not be adequately measured. This issue warrants further study because of the potential impacts on health care expenditures.

Cost-effectiveness of thrombolytic therapy for acute myocardial infarction

OBJECTIVE

To estimate the cost-effectiveness of thrombolytic therapy versus no thrombolytic therapy for patients following acute myocardial infarction, focusing on the impact of time to treatment on outcome.

METHODS

A decision model was developed to assess the benefits, risks, and costs associated with thrombolytic therapy for treatment of acute myocardial infarction compared with standard nonthrombolytic therapy. The model used pooled data from a recent study of nine large randomized, controlled clinical trials and 12-month outcome data from a recently published meta-analysis of thrombolytic therapy trial data. Outcomes were expressed in terms of survival to hospital discharge and survival to 1 year after discharge. The risks of treatment that led to death, morbidity, or added costs were estimated. The model determined excess and marginal costs per death averted to hospital discharge and at 1 year. Results were also estimated in terms of cost per year of life saved. Sensitivity analyses included variations in time to treatment and drug cost.

RESULTS

The marginal cost of thrombolytic therapy per death averted at 1 year was $222,344, or $14,438 per year of life saved. For patients treated within 6 hours of acute myocardial infarction, the marginal cost per death averted was $181,536 at 1 year, or $11,788 per year of life saved.

CONCLUSIONS

Thrombolytic therapy is significantly more cost-effective than many other cardiovascular interventions and compares favorably with other forms of medical therapy. Results suggest that shortening the time to treatment has a critical impact on the cost-effectiveness of thrombolytic therapy.

A cost-effectiveness model of thrombolytic therapy for acute myocardial infarction

OBJECTIVE

To assess the short- and long-term costs and clinical and quality of life outcomes with the use of streptokinase (SK) vs tissue plasminogen activator (tPA) for acute myocardial infarction (MI).

DESIGN

A decision analysis model.

PATIENTS

Patients with acute MI who were candidates for thrombolytic therapy and who presented within six hours of symptom onset.

MEASUREMENTS

30-day and one-year mortality, impacts of disabling and nondisabling stroke, reinfarction, hemorrhage, hypotension, anaphylaxis, and long-term medical costs.

RESULTS

Using 30-day mortality data from the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) trial, the baseline analysis yielded an incremental cost-effectiveness for tPA of $30,300 per additional quality-adjusted life year (QALY) gained, compared with SK. Using one-year mortality data from the GUSTO trial, the analysis yielded an incremental cost-effectiveness for tPA of $27,400 per additional QALY, compared with SK. The incremental cost-effectiveness of tPA over SK was sensitive to the difference in mortality seen with the two agents, exceeding $100,000 per QALY, for a relative survival advantage of approximately one-third that seen in the GUSTO trial. The incremental cost per QALY of tPA remained under $60,000 if the survival benefit was half that seen in the GUSTO trial. The cost-effectiveness of tPA declined with a shorter projected life expectancy following MI and for inferior (vs anterior) wall infarction. The analysis was modestly sensitive to the costs of the thrombolytic agents.

CONCLUSIONS

In spite of its higher cost relative to SK, tPA is a cost-effective therapy for MI under a wide range of assumptions regarding clinical outcomes and costs.

Cost and quality of life: thrombolysis and primary angioplasty

In an era of limited health care resources, analyses of the cost-effectiveness of cardiac interventions are becoming increasingly important. By generally accepted cost-effectiveness methodologies, the incremental cost for thrombolysis with streptokinase in patients with acute myocardial infarction ranges from approximately $3,500 to approximately $21,000/year of life saved. The estimated incremental cost-effectiveness of tissue-type plasminogen activator (t-PA) compared with streptokinase ranges from approximately $16,000 to $60,000/year of life saved. Pooled results of three randomized trials suggest that primary angioplasty can reduce mortality by as much as 63% without any increase in cost. This potential benefit is substantially greater than the 10% to 15% relative mortality rate reduction for each hour earlier that thrombolytic therapy is administered or the 12% relative benefit suggested for accelerated t-PA compared with that for streptokinase. Large-scale randomized trials are encouraged to determine whether the cost and mortality of population-based strategies using primary angioplasty are better than strategies that rely on intravenous thrombolysis.

Cost effectiveness of thrombolytic therapy with tissue plasminogen activator as compared with streptokinase for acute myocardial infarction

BACKGROUND

Patients with acute myocardial infarction who were treated with accelerated tissue plasminogen activator (t-PA) (given over a period of 1 1/2 hours rather than the conventional 3 hours, and with two thirds of the dose given in the first 30 minutes) had a 30-day mortality that was 15 percent lower than that of patients treated with streptokinase in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) study. This was equivalent to an absolute decrease of 1 percent in 30-day mortality. We sought to assess whether the use of t-PA, as compared with streptokinase, is cost effective.

METHODS

Our primary, or base-case, analysis of cost effectiveness used data from the GUSTO study and life expectancy projected on the basis of the records of survivors of myocardial infarction in the Duke Cardiovascular Disease Database. In the primary analysis, we assumed that there were no additional treatment costs due to the use of t-PA after the first year and that the comparative survival benefit of t-PA was still evident one year after enrollment.

RESULTS

One year after enrollment, patients who received t-PA had both higher costs ($2,845) and a higher survival rate (an increase of 1.1 percent, or 11 per 1000 patients treated) than streptokinase-treated patients. On the basis of the projected life expectancy of each treatment group, the incremental cost-effectiveness ratio--with both future costs and benefits discounted at 5 percent per year--was $32,678 per year of life saved. The use of t-PA was least cost effective in younger patients and most cost effective in older patients. At all ages, the use of t-PA in patients with anterior infarctions yielded more favorable cost-effectiveness values. In our secondary analyses, the cost-effectiveness values were most sensitive to a lowering of the projected long-term survival benefits of t-PA and to moderate or greater increases in the projected medical costs for patients in the t-PA group after the first year. In contrast, our results were not sensitive to even very unfavorable assumptions about the additional costs associated with the higher rate of disabling stroke that was noted in patients treated with t-PA in the GUSTO study.

CONCLUSIONS

The cost effectiveness of treatment with accelerated t-PA rather than streptokinase compares favorably with that of other therapies whose added medical benefit for dollars spent is judged by society to be worthwhile.

Cost-effectiveness analysis in heart disease, Part III: Ischemia, congestive heart failure, and arrhythmias

Cost-effectiveness analyses were reviewed in the following diagnostic and treatment categories: acute myocardial infarction (MI) and diagnostic strategies for coronary artery disease (CAD), coronary artery bypass graft (CABG) surgery, percutaneous transluminal coronary angioplasty (PTCA), congestive heart failure (CHF), and arrhythmias. In the case of acute MI, coronary care units, as presently used, are rather expensive but could be made much more efficient with more effective triage and resource utilization; reperfusion via thrombolysis is cost-effective, as are beta-blockers and angiotensin-converting enzyme (ACE) inhibitors post-MI in appropriate patients. Cost-effectiveness of CAD screening tests depends strongly on the prevalence of disease in the population studied. Cost-effectiveness of CABG surgery depends on targeting; eg, it is highly effective for such conditions as left-main and three-vessel disease but not for lesser disease. PTCA appears to be cost-effective in situations where there is clinical consensus for its use, eg, severe ischemia and one-vessel disease, but requires further analysis based on randomized data; coronary stents also appear to be cost-effective. In preliminary analysis, ACE inhibition for CHF dominates, ie, saves both money and lives. Cardiac transplant appears to be cost-effective but requires further study. For arrhythmias, implantable cardioverter defibrillators are cost-effective, especially the transvenous device, in life-threatening situations; radiofrequency ablation is also cost-effective in patients with Wolff-Parkinson-White syndrome apart from asymptomatic individuals; and pacemakers have not been analyzed except in the case of biofascicular block, where results were variable depending on the situation and preceding tests.

Thrombolysis in thromboembolic diseases

Thrombolysis in many manifestations of thromboembolic disease offers a valuable alternative to surgery. However, as thrombolysis is always associated with a bleeding hazard (though low) one should always weigh the risks against the expected benefits when the decision for or against this therapeutic option is made. Furthermore, in selecting the appropriate thrombolytic agent, one should be led by the urgency of reperfusion to maintain organ function. If one decides on an aggressive, high-dose, brief-duration regimen, reperfusion may be achieved more rapidly but may be incomplete in the majority of cases. On the other hand, by selecting an intermediate- or long-duration, low-dose regimen, reperfusion may happen too late to improve the patient's prognosis. Above all, one should keep in mind that the hazard of serious bleeding constantly increases with duration of thrombolysis. No matter which strategy is regarded as the best to resolve a clot in a particular patient with a particular type of thromboembolic disease, thrombolysis should be accompanied by high doses of i.v. heparin. Finally, if bleeding occurs in spite of all precautions taken, the new generation of fibrin-specific thrombolytic agents offers the advantage of short half-lives. In addition--in contrast to streptokinase--the hemostatic defect that they cause may be rapidly reversed by the infusion of antagonist drugs such as aprotinin, tranexamic acid, or epsilon-aminocaproic acid. This adds to the clinical safety profile of these thrombolytic agents.

Cost-effectiveness of streptokinase for acute myocardial infarction: A combined meta-analysis and decision analysis of the effects of infarct location and of likelihood of infarction

OBJECTIVE

To determine the effects of infarct location and of the likelihood of infarction on the cost-effectiveness of intravenous streptokinase (IVSK) for suspected acute myocardial infarction (AMI).

DESIGN

A meta-analysis of short-term survival was combined with a simple decision tree to determine marginal cost-effectiveness ratios for different infarct locations and different likelihoods of AMI (pMI).

SETTING

Six randomized trials comparing IVSK with conservative treatment.

PATIENTS

31,940 patients with onset of symptoms of AMI from four to 24 hours earlier and, with the exception of one trial, electrocardiographic abnormalities. Patients with contraindications to thrombolytic treatment such as uncontrolled hypertension were excluded.

MAIN RESULTS

If AMI is certain, treatment with IVSK has marginal cost-effectiveness ratios for each additional life saved of $9,900, $56,600, and $28,400, respectively, for patients with anterior, inferior, and other locations of AMI. If pMI is 50% treatment with IVSK has marginal cost-effectiveness ratios for each additional life saved of $22,700, $131,800, and $63,100, respectively, for patients with anterior, inferior, and other locations of AMI.

CONCLUSIONS

The marginal cost-effectiveness ratio for IVSK therapy of inferior infarction is six times that for anterior infarction and rises steeply as the presence of AMI becomes less certain. Assuming society is willing to pay $250,000 per life saved, IVSK therapy should be given if the chance of acute anterior infarction exceeds 7%, if the chance of inferior infarction exceeds 32%, or if the chance of infarction in other locations exceeds 17%. In patients with suspected acute myocardial infarction, IVSK saves lives and is a reasonable use of societal resources.

Expanding indications for thrombolytic therapy in acute myocardial infarction. How late is too late, and how early is early: the clinician's view of the first 100 minutes

Proper understanding of the pathologic process of a ruptured plaque followed by thrombus formation, with acute assessment of the deranged pathophysiology of the coronary circulation as a sequel, remains the basis for rational therapy of cardiac ischemia. With the advent of better thrombolytic regimens, improved direct reperfusion via angioplasty, and streamlined recognition/admission procedures, therapeutic strategies for dealing with acute myocardial infarction have once more turned to the options for early therapy. From recent studies of out-of-hospital thrombolysis or immediate percutaneous transluminal coronary angioplasty, the position is reinforced that "early" means the first 100 minutes. It is hoped that the large Global Utilization of Streptokinase and t-PA for Occluded Arteries (GUSTO) study, which specifically analyses the effect of early reperfusion by optimal alteplase and actilyse (recombinant tissue-type plasminogen activator [rt-PA]) versus streptokinase regimens will confirm this essential concept once and for all. Thus, when appropriate therapy--depending in the local availability of facilities--is promptly given, further reductions in myocardial infarction size and ventricular dysfunction can be achieved, resulting in mortality rates < 5%, at substantial savings in ever more expensive healthcare resources. "Early is < 100 minutes; later may be too late or too costly."

The relation between experience and outcome in heart transplantation

BACKGROUND

Current policies related to organ transplantation in the United States are designed to ensure that centers and physicians with experience in transplantation perform these procedures. It is essential to confirm the validity of such policies, since they may limit access to transplantation services.

METHODS

To determine the relation between experience with heart transplantation and mortality after the procedure, we merged data from the registry of the International Society for Heart and Lung Transplantation with data from a survey that provided additional information about patients and transplantation centers. Our study included 1123 patients who received a heart transplant at one of 56 hospitals in the United States from 1984 through 1986. We used univariate and bivariate techniques, as well as logistic regression, to analyze our data.

RESULTS

We observed an institutional learning curve for heart transplantation. Patients who received one of a center's first five transplants had higher mortality rates than patients who received a subsequent transplant (20 percent vs. 12 percent; P = 0.002; relative risk = 2.2; 95 percent confidence interval, 1.6 to 3.4). In addition, we found a correlation between the training of key personnel on the transplantation team and mortality at new transplantation centers. For example, new centers staffed by cardiologists with previous training in heart transplantation had lower mortality rates among heart-transplant recipients than centers without experienced cardiologists (7 percent vs. 16 percent; P = 0.001; relative risk = 2.7; 95 percent confidence interval, 1.3 to 5.9). By contrast, the previous training of the surgeons who performed transplantations was not related to the mortality rate associated with the procedure.

CONCLUSIONS

Experience with heart transplantation is associated with a better outcome for patients after that procedure. Opportunities exist to refine transplantation policies on the basis of the experience of a center and its transplantation team and to develop similar policies for other forms of organ transplantation.

One-year outcome after therapy with tissue plasminogen activator: report from the Thrombolysis and Angioplasty in Myocardial Infarction trial

To evaluate the long-term effects of reperfusion with tissue plasminogen activator (t-PA) and an aggressive strategy of revascularization with angioplasty and coronary artery bypass grafting, we obtained 1-year follow-up results from 386 consecutive patients enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI I) trial. All patients were treated with 100 to 150 mg of t-PA intravenously over 6 to 8 hours, and coronary angiography was performed within 90 minutes of initiation of therapy. In 197 patients with suitable anatomic characteristics, angioplasty was either performed immediately or was deferred for 7 to 10 days on a randomized basis. The remainder of the patients were treated as considered clinically appropriate. The in-hospital mortality rate was 7%, and only 1.9% of patients died in the first year after discharge from the hospital; three patients died of cardiac events and four died of noncardiac causes. Ninety-four percent of patients discharged alive from the hospital remained alive and had no myocardial infarctions during the first 12 posthospital months. Revascularization procedures after discharge from the hospital included angioplasty in 8% of patients and coronary artery bypass grafting in 5%. The high survival rates were evident in high-risk groups defined by age, ejection fraction, and extent of coronary artery disease. At 1-year follow-up 64% of patients less than 65 years of age were employed and only 10% reported that they were disabled; 94% of patients were in Canadian Heart Association class I or II. These low rates of follow-up events suggest a change in the "natural history" of the first year after acute myocardial infarction.

Cost-effectiveness perspectives in coronary heart disease

In the United States there has been a dramatic decrease in age-adjusted coronary heart disease (CHD) mortality during the last 20 years. This article investigates the reasons for this decline and concludes that most of the decline in CHD has been the result of life-style changes, particularly reduction in serum cholesterol and cigarette smoking. The CHD Policy Model is used to compare the effect of a targeted versus a population-wide program of cholesterol reduction. On the basis of these projections, population-wide interventions are considered an important part of cholesterol reduction programs. The article also assesses the cost-effectiveness of selected cardiac interventions, for example, screening exercise tolerance tests, coronary care units, thrombolysis in acute myocardial infarction, and beta-blockers in patients after myocardial infarction. Cost-effectiveness analysis is seen to be crucial as medical costs escalate and the population at risk from CHD increases.

Outcome assessment in cardiovascular cost-benefit studies

The scarcity of health resources and development of new treatments have introduced a need to assess health care interventions in the areas of both costs and benefits. Information on costs and benefits of one treatment program relative to another can assist decisions about resource allocation by indicating which interventions offer the greatest benefit at the least cost. Economic evaluation is dependent on accurate definition and appropriate measurement of outcome or benefit. This article reviews a number of evaluation techniques and cost-benefit studies associated with cardiovascular medicine. The focus is on health-related quality of life, the methodology, and the problems encountered therein. Methods for combining quantity and quality of life are discussed with reference to a composite measure of health outcome, quality-adjusted life years.

Practice guidelines and professional autonomy in a universal health insurance system: the case of tissue plasminogen activator in Ontario

Ontario's universal health insurance system has placed few constraints on the clinical and economic autonomy of medical doctors. Although fees are standardized, most physicians remain in private fee-for-service practice and thereby retain control of the mix and volume of services. Utilization review is minimal. While organized medicine has argued that health care is 'under-funded', the government is pressing for better use of extant resources through firmer management of the medical services sector. The Ontario Medical Association (OMA), the major bargaining agent for doctors in the province, has accordingly sought to protect professional autonomy by developing voluntary self-regulatory approaches that obviate the need for external controls over physician practice patterns. Part of this strategy is promulgation of practice guidelines. Tissue plasminogen activator (t-PA), a clot-lysing drug for myocardial infarction, was released in late 1987, and, at C$2950 per treatment, constituted an unforeseen add-on cost for hospitals. The OMA subsequently convened an expert panel to develop guidelines for thrombolysis in myocardial infarction. Among the unanticipated results was the conclusion that insufficient evidence had accumulated to recommend routine use of t-PA instead of streptokinase, an older drug costing C$290. The OMA panel's guidelines were approved by the OMA executive, and led the government to reject special add-on funding for hospitals purchasing t-PA. The OMA's position and government decision provoked negative reactions from the OMA's own cardiology section. Indicative of clinicians' feelings, a follow-up survey of cardiologists and internists showed that only 28% of respondents were indifferent between t-PA and streptokinase, while 64% preferred t-PA. On the other hand, 74% supported clinical policy development by the OMA, while 94% opposed direct government involvement in guideline-setting. The case of the OMA thrombolysis guidelines illustrates a strategic conundrum facing Canadian organized medicine. Professional activism in guideline-setting may in theory protect the individual practitioner's autonomy by offering a voluntary alternative to utilization management by government, and is likely to strengthen the collective influence of organized medicine. However, among the risks are alienation of practitioners who see professional guidelines and government control as two sides of the same regulatory coin, and the transmogrification of voluntary guidelines into parameters for cost control and utilization management by government or hospitals. Future initiatives will depend on how these benefits and risks are weighed.

Long-term benefit of early thrombolytic therapy in patients with acute myocardial infarction: 5 year follow-up of a trial conducted by the Interuniversity Cardiology Institute of The Netherlands

Patients (n = 533) who participated in the Interuniversity Cardiology Institute of the Netherlands Trial were followed up for 3 to 7 years. The 5 year survival rate after thrombolytic therapy with intracoronary streptokinase was 81% (269 patients) compared with 71% after conventional therapy (264 patients). The greatest improvement in survival was observed in patients with anterior infarction (81% versus 64% with thrombolytic therapy or conventional therapy, respectively), in those with heart failure on admission or a previous infarction and in those with extensive myocardial ischemia on admission. Left ventricular ejection fraction at the time of hospital discharge was better after thrombolytic therapy. In the hospital survivors, long-term outcome was related to left ventricular function at the time of discharge and, to a lesser extent, to the underlying coronary artery disease. The initial therapy (thrombolysis or conventional) was not an independent additional determinant of long-term survival when left ventricular function and coronary status at the time of hospital discharge were taken into account. Thus, the salutary effects of thrombolytic therapy appear to be the result of myocardial salvage. Reinfarction within 3 years was observed more frequently after thrombolytic therapy, particularly in patients with inferior wall infarction and those with greater than or equal to 90% stenosis of the infarct-related vessel at discharge. Coronary bypass surgery and coronary angioplasty were performed more frequently after thrombolytic therapy than in conventionally treated patients. At 5 years, approximately 40% of patients in both groups had an uneventful course without reinfarction or additional revascularization procedures. These observations demonstrate that the benefits of thrombolytic therapy are maintained throughout 5 years of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

The cost:benefit ratio of acute intervention for myocardial infarction: results of a prospective, matched pair analysis

Parallel to the increased acceptance of intervention for acute myocardial infarction, there has been a decrease in financial resources and reimbursement. To ascertain the relative cost to benefit of intervention, we evaluated 78 matched pairs of acute myocardial infarction patients from a prospective data base of 507 consecutive patients presenting with infarction from May 1986 to July 1987. The pairs were matched for age (mean 61 years), sex (68% male), and infarct location (43% anterior). Intervention (thrombolytics and/or percutaneous transluminal coronary angioplasty [PTCA]) was only applied to patients at less than 6 hours from symptom onset. Nonintervention patients were subsequently considered for angiography and revascularization (PTCA, coronary artery bypass grafting [CABG]) based on clinical criteria. Clinical outcome was evaluated by in-hospital mortality and uncomplicated status (free of angina, heart failure, or arrhythmias) at 72 hours. Intervention was associated with decreased mortality (5.3% versus 13%, p = 0.16) and increased uncomplicated course (43% versus 19%, p less than 0.001) as compared with patients not receiving intervention. Hospital procedures for the intervention and nonintervention group were as follows: diagnostic cardiac catheterization (99% versus 51%); PTCA (60% versus 0%); and CABG (14% versus 19%), respectively. The mean cumulative hospital and professional charges were $31,684 for the intervention group and $29,022 for the nonintervention group (p = 0.50). In conclusion, despite the potential marked incremental expense of technology associated with intervention for acute myocardial infarction, this analysis demonstrates that benefit in clinical outcome can be derived without substantially increased costs.

Cost and procedure implications of thrombolytic therapy for acute myocardial infarction

A computer model was developed to analyze the costs to Medicare and the potential procedure volume associated with alternative strategies for treatment of acute myocardial infarction. The expected cost per case to Medicare for initial hospitalization was approximately $7,200 for conventional treatment, $7,900 for treatment with intravenous streptokinase and $8,400 for treatment with recombinant tissue-type plasminogen activator (rt-PA). The expected cost per case for use of streptokinase or rt-PA in combination with cardiac catheterization performed either emergently or at 48 h was in excess of $11,000. These cost estimates do not reflect the cost of thrombolytic drugs themselves because Medicare has not adjusted its hospital payment rates to take account of such costs. Although both streptokinase and rt-PA will increase costs to Medicare for hospitalizations for acute myocardial infarction, both agents will do so at a reasonably low cost per additional life saved--between $50,000 and $60,000. Emergency and 48 h catheterization strategies are considerably less cost-effective. Regarding procedures, this model suggests that for every 1,000 patients treatment with streptokinase will result in an additional 76 coronary angioplasty procedures and 26 coronary artery bypass operations, whereas treatment with rt-PA will result in an additional 122 angioplasty procedures and 43 bypass operations compared with conventional treatment. Thrombolytic treatment is thus likely to increase substantially the volume of cardiac catheterization, coronary angioplasty and coronary artery bypass surgery performed in the United States.

A randomized controlled trial of hospital discharge three days after myocardial infarction in the era of reperfusion

To evaluate the feasibility and cost savings of hospital discharge three days after acute myocardial infarction, we screened 507 consecutive patients prospectively for clinical complications and exercise-test performance. Of 179 patients whose condition was classified as uncomplicated (no angina, heart failure, or arrhythmia 72 hours after admission), 126 underwent early exercise testing and 90 had no provocable myocardial ischemia. Eighty of these patients were randomly assigned to early (day 3) or conventional (days 7 to 10) hospital discharge. Seventy-six of them had received coronary reperfusion therapy (thrombolysis, angioplasty, or both). At six months of follow-up, there were no deaths or new ventricular aneurysms, and the early-discharge and conventional-discharge groups had similar numbers of hospital readmissions (6 and 10), reinfarctions (none and 5), and patients with angina (3 and 8). In the early-discharge group, 25 of 29 previously employed patients returned to work 40.7 +/- 21.9 days (mean +/- SD) after admission, as compared with 25 of 27 patients in the conventional-discharge group, who returned to work after a mean of 56.9 +/- 30.3 days (P = 0.054). The mean cumulative hospital and professional charges were $12,546 +/- 3,034 in the early-discharge group, as compared with $17,868 +/- 3,688 in the conventional-discharge group (P less than 0.0001). In carefully selected patients with uncomplicated myocardial infarction, hospital discharge after three days is feasible and leads to a substantial reduction in hospital charges. Before this strategy can be widely recommended, however, its safety must be confirmed in larger prospective clinical trials.