Myocardial revascularization for chronic stable angina. Analysis of the role of percutaneous transluminal coronary angioplasty based on data available in 1989

No prospective, randomized clinical trial comparing coronary artery bypass grafting, percutaneous transluminal coronary angioplasty, and conservative therapy has been reported. To address when revascularization is indicated, we constructed a decision analytic model. Our model incorporates procedure-related mortality and morbidity, coronary artery disease-related mortality, and the benefit of revascularization. We determined the quality-adjusted life expectancy and expected costs for each strategy. Our model suggests that angioplasty is a reasonable alternative to bypass surgery in patients with favorable lesions if angioplasty would provide a comparable degree of revascularization. Our model predicts that patients treated with angioplasty will have more revascularization procedures than will patients treated with bypass surgery but predicts that both treatments will cost the same over the typical patient's lifetime. In many patients with severe angina or documented ischemia, angioplasty is indicated for stenosis of a single artery. In patients with two vessel disease that is amenable to angioplasty, angioplasty may be a reasonable alternative to bypass surgery. Even in patients whose three vessel disease can be completely revascularized by angioplasty, bypass surgery, although relatively expensive, is slightly better than angioplasty. In patients with three vessel disease and comorbidities that increase operative risk, angioplasty may be a reasonable alternative to either bypass surgery or medical therapy.

Stroke after coronary artery operation: incidence, correlates, outcome, and cost

BACKGROUND

Stroke is a major complication of coronary operation, with reported rates of postoperative cerebral dysfunction ranging from 0.4% to 13.8%. In this report, the incidence, correlates, outcomes, and costs of stroke in coronary operation were evaluated at Emory University between 1988 and 1996.

METHODS

Data were entered prospectively into a dedicated computerized database at Emory University and analyzed retrospectively. Univariate and multivariate analyses were utilized where appropriate.

RESULTS

Data from 10,860 patients undergoing primary coronary operation between 1988 and 1996 were analyzed. There were 250 patients not entered into the database. Stroke occurred in 244 (2.2%). Univariate predictors of stroke (p<0.05) included age, female gender, hypertension, diabetes, prior stroke, prior transient ischemic attack (TIA), and carotid bruits. Multivariate correlates included age (odds ratio 1.07) previous TIA (odds ratio 2.2), and carotid bruits (odds ratio 1.9), although the area under the Receiver Operating Characteristics (ROC) curve was only 0.69, suggesting limited ability to predict stroke. One and 5 year survival rates were 64% and 44% with stroke, and 94% and 81% without stroke, respectively. Among the stroke group, 23% of the patient population died before hospital discharge. The stroke group had a significantly longer length of hospital stay, as well as higher costs.

CONCLUSIONS

Stroke is a devastating complication of coronary operation, significantly increasing morbidity, mortality, and cost. Three independent variables were identified for predicting stroke, including age, previous TIA, and carotid bruits. Patients should be carefully screened for cerebrovascular disease to help prevent stroke and its associated morbidity.

Helicopters, hearts and hips: using willingness to pay to set priorities for public sector health care programmes

The paper reports from a study that asked 150 interviewees their willingness to pay (WTP) in increased earmarked taxation for three different health care programmes: a helicopter ambulance service, more heart operations and more hip replacements. Reasons behind the stated WTP were asked for. Ordinary least squares regression analyses were used to analyse factors associated with WTP for each of the three programmes, and factors associated with the relative WTP for one programme compared with the total of the three. Comparisons were made of WTP for these programmes and the health outcome in terms of quality adjusted life years.

Economics of myocardial perfusion imaging in Europe--the EMPIRE Study

BACKGROUND

Physicians use myocardial perfusion imaging to a variable extent in patients presenting with possible coronary artery disease. There are few clinical data on the most cost-effective strategy although computer models predict that routine use of myocardial perfusion imaging is cost-effective.

OBJECTIVES

To measure the cost-effectiveness of four diagnostic strategies in patients newly presenting with possible coronary artery disease, and to compare cost-effectiveness in centres that routinely use myocardial perfusion imaging with those that do not.

METHODS

We have studied 396 patients presenting to eight hospitals for the diagnosis of coronary artery disease. The hospitals were regular users or non-users of myocardial perfusion imaging with one of each in four countries (France, Germany, Italy, United Kingdom). Information was gathered retrospectively on presentation, investigations, complications, and clinical management, and patients were followed-up for 2 years in order to assess outcome. Pre- and post-test probabilities of coronary artery disease were computed for diagnostic tests and each test was also assigned as diagnostic or part of management. Diagnostic strategies defined were: 1: Exercise electrocardiogram/coronary angiography, 2: exercise electrocardiogram/myocardial perfusion imaging/coronary angiography, 3: myocardial perfusion imaging/coronary angiography, 4: coronary angiography. Primary outcome measures were the cost and accuracy of diagnosis, the cost of subsequent management, and clinical outcome. Secondary measures included prognostic power, normal angiography rate, and rate of angiography not followed by revascularization.

RESULTS

Mean diagnostic costs per patient were: strategy 1: 490 Pounds, 2: 409 Pounds, 3: 460 Pounds, 4: 1253 Pounds (P < 0.0001). Myocardial perfusion imaging users: 529 Pounds, non-users 667 Pounds (P = 0.006). Mean probability of the presence of coronary artery disease when the final clinical diagnosis was coronary artery disease present were, strategy 1: 0.85, 2: 0.82, 3: 0.97, 4: 1.0 (P < 0.0001), users 0.93, non-users 0.88 (P = 0.02), and when coronary artery disease was absent, 1: 0.26, 2: 0.22, 3: 0.16, 4: 0.0 (P < 0.0001), users 0.21, non-users 0.20 (P = ns). Total 2-year costs (coronary artery disease present/absent) were: strategy 1: 4453 Pounds/710 Pounds, 2: 3842 Pounds/478 Pounds, 3: 3768 Pounds/574 Pounds, 4: 5599 Pounds/1475 Pounds (P < 0.05/0.0001), users: 5563 Pounds/623 Pounds, non-users: 5428 Pounds/916 Pounds (P = ns/0.001). Prognostic power at diagnosis was higher (P < 0.0001) and normal coronary angiography rate lower (P = 0.07) in the scintigraphic centres and strategies. Numbers of soft and hard cardiac events over 2 years and final symptomatic status did not differ between strategy or centre.

CONCLUSION

Investigative strategies using myocardial perfusion imaging are cheaper and equally effective when compared with strategies that do not use myocardial perfusion imaging, both for cost of diagnosis and for overall 2 year management costs. Two year patient outcome is the same.

Cost-effectiveness of cell salvage and alternative methods of minimising perioperative allogeneic blood transfusion: a systematic review and economic model

OBJECTIVES

To compare patient outcomes, resource use and costs to the NHS and NHS Blood Transfusion Authority (BTA) associated with cell salvage and alternative methods of minimising perioperative allogeneic blood transfusion.

DATA SOURCES

Electronic databases covering the period 1996-2004 for systematic reviews and 1994-2004 for economic evidence.

REVIEW METHODS

Existing systematic reviews were updated with data from selected randomised controlled trials (RCTs) that involved adults scheduled for elective non-urgent surgery. Any resource use or cost data were extracted for potential use in populating an economic model. Relative risks or weighted mean difference of each outcome for each intervention were assessed, taking into account the number of RCTs included in each outcome and intervention and the presence of any heterogeneity. This allowed indirect comparison of the relative effectiveness of each intervention when the intervention is compared with allogeneic blood transfusion. A decision analytic model synthesised clinical and economic data from several sources, to estimate the relative cost-effectiveness of cell salvage for people undergoing elective surgery with moderate to major expected blood loss. The perspective of the NHS and patients and a time horizon of 1 month were used. The economic model was developed from reviews of effectiveness and cost-effectiveness and clinical experts. Secondary analysis explored the robustness of the results to changes in the timing and costs of cell salvage equipment, surgical procedure, use of transfusion protocols and time horizon of analysis.

RESULTS

Overall, 668 studies were identified electronically for the update of the two systematic reviews. This included five RCTs, of which two were cell salvage and three preoperative autologous donation (PAD). Five published systematic reviews were identified for antifibrinolytics, fibrin sealants and restrictive transfusion triggers, PAD plus erythropoietin, erythropoietin alone and acute normovolaemic haemodilution (ANH). Twelve published studies reported full economic evaluations. All but two of the transfusion strategies significantly reduced exposure to allogeneic blood. The relative risk of exposure to allogeneic blood was 0.59 for the pooled trials of cell salvage (95% confidence interval: 0.48 to 0.73). This varied by the type and timing of cell salvage and type of surgical procedure. For cell salvage, the relative risk of allogeneic blood transfusion was higher in cardiac surgery than in orthopaedic surgery. Cell salvage had lower costs and slightly higher quality-adjusted life years compared with all of the alternative transfusion strategies except ANH. The likelihood that cell salvage is cost-effective compared with strategies other than ANH is over 50%. Most of the secondary analyses indicated similar results to the primary analysis. However, the primary and secondary analyses indicated that ANH may be more cost-effective than cell salvage.

CONCLUSIONS

The available evidence indicates that cell salvage may be a cost-effective method to reduce exposure to allogeneic blood transfusion. However, ANH may be more cost-effective than cell salvage. The results of this analysis are subject to the low quality and reliability of the data used and the use of indirect comparisons. This may affect the reliability and robustness of the clinical and economic results. There is a need for further research that includes adequately powered high-quality RCTs to compare directly various blood transfusion strategies. These should include measures of health status, health-related quality of life and patient preferences for alternative transfusion strategies. Observational and tracking studies are needed to estimate reliably the incidence of adverse events and infections transmitted during blood transfusion and to identify the lifetime consequences of the serious hazards of transfusion on mortality, health status and health-related quality of life.

A comparison of several regression models for analysing cost of CABG surgery

Investigators in clinical research are often interested in determining the association between patient characteristics and cost of medical or surgical treatment. However, there is no uniformly agreed upon regression model with which to analyse cost data. The objective of the current study was to compare the performance of linear regression, linear regression with log-transformed cost, generalized linear models with Poisson, negative binomial and gamma distributions, median regression, and proportional hazards models for analysing costs in a cohort of patients undergoing CABG surgery. The study was performed on data comprising 1959 patients who underwent CABG surgery in Calgary, Alberta, between June 1994 and March 1998. Ten of 21 patient characteristics were significantly associated with cost of surgery in all seven models. Eight variables were not significantly associated with cost of surgery in all seven models. Using mean squared prediction error as a loss function, proportional hazards regression and the three generalized linear models were best able to predict cost in independent validation data. Using mean absolute error, linear regression with log-transformed cost, proportional hazards regression, and median regression to predict median cost, were best able to predict cost in independent validation data. Since the models demonstrated good consistency in identifying factors associated with increased cost of CABG surgery, any of the seven models can be used for identifying factors associated with increased cost of surgery. However, the magnitude of, and the interpretation of, the coefficients vary across models. Researchers are encouraged to consider a variety of candidate models, including those better known in the econometrics literature, rather than begin data analysis with one regression model selected a priori. The final choice of regression model should be made after a careful assessment of how best to assess predictive ability and should be tailored to the particular data in question.

Long-term survival and functional capacity in cardiac surgery patients after prolonged intensive care

OBJECTIVE

To determine whether hospital discharge alone represents a good outcome for patients who had prolonged intensive care after cardiac surgery by studying their postdischarge survival and functional outcome. The secondary objective is to estimate the proportion of intensive care unit (ICU) resources used by the long-stay (> or = 10 initial consecutive ICU days) patients and to identify preoperative patient characteristics that are associated with a prolonged ICU stay and hospital and long-term survival.

DESIGN

Inception cohort study.

SETTING

The Cleveland Clinic Foundation, a tertiary care, academic teaching institution.

PATIENTS

Cardiac surgery patients with an initial ICU stay of 10 or more consecutive days.

INTERVENTIONS

Data were collected daily during hospitalization on every adult who underwent coronary artery bypass graft and/or valve surgery at one institution in 1993. Discharged patients who spent >10 initial consecutive days in the ICU after surgery were contacted by telephone to determine vital status and functional capacity using the Duke Activity Status Index. Total ICU and total hospital direct costs were obtained for each patient.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measurements were ICU length of stay, hospital mortality, after-surgery and postdischarge mortality and functional capacity, and relative resource utilization. Of the 2,618 cardiac surgery patients who met the inclusion criteria, 142 (5.4%) had an initial ICU length of stay of 10 or more consecutive days. Of these, 47 (33.1%) died in the hospital. Ninety-four of the 95 discharged patients were followed up (median follow-up, 30.6 months), and 44 of the 94 (46.8%) died during the follow-up period. The median Duke Activity Status Index for the 50 survivors was 26 out of a possible 58.2. The 142 long-stay patients used 50% of the total ICU days and 48% of the total ICU direct cost for all 2,618 patients.

CONCLUSIONS

Many survivors of prolonged intensive care die soon after hospital discharge and many longer term survivors have a poor functional state. Therefore, hospital discharge is an incomplete measure of outcome for these patients, and longer follow-up is more appropriate. The relatively small number of patients who require prolonged intensive care consumes a disproportionate amount of the total ICU and total hospital direct cost.

Racial and ethnic disparities in the use of cardiovascular procedures: associations with type of health insurance

OBJECTIVES

This study examined whether disparities in the use of cardiovascular procedures exist among African Americans, Latinos, and Asians relative to White patients, within health insurance categories.

METHODS

Hospital discharge records (n = 104,952) of Los Angeles Country, California, residents with possible coronary artery disease were analyzed.

RESULTS

After adjustment for confounders, lower odds of procedure use were found for African American and Latino patients for most types of insurance. Asians and Pacific Islanders had odds of procedure use similar to those of White patients. Disparities were absent among the privately insured.

CONCLUSIONS

Racial and ethnic disparities in procedure rates were evident in all types of insurance except private insurance.

Economics of elective coronary revascularization. Comparison of costs and charges for conventional angioplasty, directional atherectomy, stenting and bypass surgery

OBJECTIVES

This study was designed to evaluate more closely the true in-hospital costs of elective revascularization by directional coronary atherectomy and intracoronary stenting and to compare these costs with those of the traditional revascularization alternatives (i.e., conventional balloon angioplasty and coronary artery bypass surgery).

BACKGROUND

Previous studies have suggested that total hospital charges for directional coronary atherectomy or intracoronary stenting are significantly higher than those for conventional angioplasty. However, hospital charges do not necessarily reflect true economic costs, and their use may provide misleading data with regard to cost-effectiveness.

METHODS

We analyzed in-hospital charges from the itemized hospital accounts of 300 patients undergoing elective angioplasty, directional atherectomy, Palmaz-Schatz coronary stenting or bypass surgery between January 1, 1990 and December 31, 1991. Costs were then derived by adjusting itemized patient accounts for department-specific cost/charge ratios. Catheterization laboratory costs were based on actual resource consumption, and daily room costs were adjusted for the intensity of nursing services provided.

RESULTS

Length of hospital stay was similar for atherectomy (2.3 +/- 1.5 days) and conventional angioplasty (2.6 +/- 1.7 days) but significantly longer for stenting (5.5 +/- 2.6 days, p < 0.05). Total costs were also significantly higher for coronary stenting ($7,878 +/- $3,270, median $6,699, p < 0.05) than for angioplasty ($5,396 +/- $2,829, median $4,753) or atherectomy ($5,726 +/- $2,716, median $4,986). However, length of stay, resource consumption (laboratory and radiologic testing, drugs, blood products, for example) and total costs for bypass surgery were still greater than for any of the percutaneous interventional procedures.

CONCLUSIONS

In contrast to previous studies utilizing only hospital charges, the in-hospital costs of angioplasty and directional coronary atherectomy were similar. Although the cost of coronary stenting was approximately $2,500 higher than that of conventional angioplasty, the magnitude of this difference was smaller than the $6,300 increment previously suggested on the basis of analysis of hospital charges. These findings reflect the inherent discrepancies between cost-based and charge-based methodologies and may have important implications for future studies evaluating the relative cost-effectiveness of newer coronary interventions.

Economic impact of inappropriate blood transfusions in coronary artery bypass graft surgery

PURPOSE

In addition to historically important issues of blood inventory and blood safety, the costs of blood transfusion are anticipated to have an increasingly important impact on transfusion practices. To address this, we analyzed costs of blood support given to patients undergoing coronary artery bypass graft (CABG) surgery, along with costs of blood components whose transfusions were identified to be unnecessary.

PATIENTS AND METHODS

Blood components transfused as part of a previously reported national, multicenter audit of 30 adult patients each at 18 institutions undergoing primary, elective CABG surgery were reviewed.

RESULTS

The range of blood purchase costs among institutions was broad, varying over two-fold. The range of red cell units transfused varied over 10-fold, and the range of total components transfused varied over 40-fold. The number of blood components transfused unnecessarily represented 27% of all blood units transfused, ranging from 7% to 43% among institutions. Inappropriate transfusions accounted for 47%, 32%, and 15% of all platelet, plasma, and red cell units transfused. The mean institutional cost for all blood components transfused per patient was $397 +/- $244. The cost per patient of components transfused inappropriately was 24% of this, or $96 +/- $89 (mean +/- SD).

CONCLUSION

These costs could be reduced with practice guidelines and quality improvement programs aimed at reducing the number of inappropriate transfusions.

Economic assessments of medical practices and technologies

Cost-effectiveness analysis can be useful as an aid to decision makers concerned with the allocation of health care resources. The approach requires an explicit, quantitative measure of the health effectiveness of the intervention under analysis, as well as a measure of its net resource cost. Cost-effectiveness analyses are less useful if the measure of effectiveness is expressed in units that are unique to the intervention or class of interventions being considered than if the measure is comparable across interventions. The life year as a unit offers the advantage of comparability across programs, but its use in cost-effectiveness analysis can be misleading if the effects of the program in question include changes in the quality of life. Cost-effectiveness analyses of estrogen therapy in the menopause, high blood pressure control, and coronary artery bypass surgery are used to illustrate the method of analysis and the sensitivity of conclusions to the manner in which quality-of-life impacts are included explicitly (or excluded entirely). Cost-effectiveness analyses, therefore, should always include sensitivity analyses in which preference weights and parameters are varied over the plausible range. Inability to measure the quality of life and preferences regarding such effects should not be an excuse for failing to include them in a cost-effectiveness analysis.

A comparison of the costs of and quality of life after coronary angioplasty or coronary surgery for multivessel coronary artery disease. Results from the Emory Angioplasty Versus Surgery Trial (EAST)

BACKGROUND

The Emory Angioplasty Versus Surgery Trial (EAST) is a randomized trial that compares, by intention to treat, the clinical outcome and costs of percutaneous transluminal coronary angioplasty (PTCA) and coronary surgery for multivessel coronary artery disease.

METHODS AND RESULTS

The primary end point was a composite of death, Q-wave myocardial infarction, and a large reversible thallium defect at 3 years. Multiple measures of quality of life also were made. Charges were assessed from the hospital UB-82 bills; professional charges were assessed from the Emory Clinic. Hospital charges were reduced to cost through step-down accounting methods. All costs and charges were deflated to 1987 dollars. Costs were assessed for the initial hospitalization and the cumulative costs of the initial hospitalization and additional revascularization procedures for up to 3 years. There was no difference in mortality or the primary end point. Mean initial hospital charges were $12,654 for the PTCA group and $20,214 for the surgery group (P < .0001). Professional charges were 4538 for PTCA and $9426 for surgery (P < .0001). Three-year hospital charges were $19,047 for PTCA and $21,174 for coronary surgery (P < .0001). Three-year professional charges were $6412 for PTCA and $9861 for surgery (P < .0001). Three-year total charges were $25,458 for PTCA and $31,033 for surgery (P < .0001). Total 3-year costs were $23,734 for PTCA and $25,310 for coronary surgery (P < .0001). There were more hospitalizations for angina and more antianginal medications used in the PTCA group, which would further narrow the differences in cost.

CONCLUSIONS

There was no difference in the primary end point or its components at 3 years. Although the primary procedural costs of coronary surgery are more than for coronary angioplasty, this cost advantage is largely, although probably not completely, lost by 3 years because of more frequent additional procedures and other resource consumption after a first revascularization by PTCA.

Effects of the Premier Hospital Quality Incentive Demonstration on Medicare patient mortality and cost

OBJECTIVE

To evaluate the effects of the Premier Inc. and Centers for Medicare and Medicaid Services Hospital Quality Incentive Demonstration (PHQID), a public quality reporting and pay-for-performance (P4P) program, on Medicare patient mortality, cost, and outlier classification.

DATA SOURCES

The 2000-2006 Medicare inpatient claims, Medicare denominator files, and Medicare Provider of Service files.

STUDY DESIGN

Panel data econometric methods are applied to a retrospective cohort of 11,232,452 admissions from 6,713,928 patients with principal diagnoses of acute myocardial infarction (AMI), heart failure, pneumonia, or a coronary-artery bypass grafting (CABG) procedure from 3,570 acute care hospitals between 2000 and 2006. Three estimators are used to evaluate the effects of the PHQID on risk-adjusted (RA) mortality, cost, and outlier classification in the presence of unobserved selection, resulting from the PHQID being voluntary: fixed effects (FE), FE estimated in the subset of hospitals eligible for the PHQID, and difference-in-difference-in-differences.

DATA EXTRACTION METHODS

Data were obtained from CMS. Principal Findings. This analysis found no evidence that the PHQID had a significant effect on RA 30-day mortality or RA 60-day cost for AMI, heart failure, pneumonia, or CABG and weak evidence that the PHQID increased RA outlier classification for heart failure and pneumonia.

CONCLUSIONS

By not reducing mortality or cost growth, this study suggests that the PHQID has made little impact on the value of inpatient care purchased by Medicare.

Cost-effectiveness of percutaneous coronary intervention with drug eluting stents versus bypass surgery for patients with diabetes mellitus and multivessel coronary artery disease: results from the FREEDOM trial

BACKGROUND

Studies from the balloon angioplasty and bare metal stent eras have demonstrated that coronary artery bypass grafting (CABG) is cost-effective compared with percutaneous coronary intervention (PCI) for patients undergoing multivessel coronary revascularization-particularly among patients with complex coronary artery disease or diabetes mellitus. Whether these results apply in the drug-eluting stent (DES) era is unknown.

METHODS AND RESULTS

Between 2005 and 2010, 1900 patients with diabetes mellitus and multivessel coronary artery disease were randomized to PCI with DES (DES-PCI; n=953) or CABG (n=947). Costs were assessed from the perspective of the U.S. health care system. Health state utilities were assessed using the EuroQOL 5 dimension 3 level questionnaire. A patient-level microsimulation model based on U.S. life-tables and in-trial results was used to estimate lifetime cost-effectiveness. Although initial procedural costs were lower for CABG, total costs for the index hospitalization were $8622 higher per patient. Over the next 5 years, follow-up costs were higher with PCI, owing to more frequent repeat revascularization and higher outpatient medication costs. Nonetheless, cumulative 5-year costs remained $3641 higher per patient with CABG. Although there were only modest gains in survival with CABG during the trial period, when the in-trial results were extended to a lifetime horizon, CABG was projected to be economically attractive relative to DES-PCI, with substantial gains in both life expectancy and quality-adjusted life expectancy and incremental cost-effectiveness ratios <$10 000 per life-year or quality-adjusted life-year gained across a broad range of assumptions regarding the effect of CABG on post-trial survival and costs.

CONCLUSIONS

Despite higher initial costs, CABG is a highly cost-effective revascularization strategy compared with DES-PCI for patients with diabetes mellitus and multivessel coronary artery disease.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinical-trials.gov. Unique identifier: NCT00086450.

Cardiac surgery in the octogenarian: evaluation of risk, cost, and outcome

BACKGROUND

Nationwide, cardiac surgery is being performed more frequently in patients aged 80 years and older.

METHODS

One hundred four octogenarians undergoing a variety of heart-lung procedures were prospectively studied between 1995 and 1998 for comparison with similar patients aged 65 to 75 years (n = 351).

RESULTS

Octogenarians were more likely to be of female gender, and be nondiabetic than the younger group. The 30-day mortality rate for patients aged 65 to 75 years was 3.4% (12 of 351 patients), versus 13.5% (14 of 104) for patients aged 80+ (p = 0.0004), which ranged from 2% (1 of 50) in nonemergent coronary artery bypass grafting to 75% (3 of 4) in double valve procedures. Complications occurring more frequently in octogenarians were severe low output state, reintubation, and atrial fibrillation. Elders experienced a longer intensive care (69.2 versus 43.3 hours, p = 0.002) and postoperative stay (10.09 versus 7.45 days, p = 0.001), and were discharged to a skilled nursing facility more often than younger patients (47% versus 21.1%, p = 0.0001). Total direct costs were $4,818 higher in the octogenarian group (p = 0.0007).

CONCLUSIONS

Although emergency operations and complex procedures carried high risks for the octogenarian, the majority of these patients can be offered operation with short-term morbidity, mortality, and resource use that only modestly exceeds that of younger patients.

"ProvenCareSM": a provider-driven pay-for-performance program for acute episodic cardiac surgical care

OBJECTIVE

To test whether an integrated delivery system could successfully implement an evidence-based pay-for-performance program for coronary artery bypass graft (CABG) surgery.

METHODS

The program consisted of 3 components: (1) establishing implementable best practices; (2) developing risk-based pricing; (3) establishing a mechanism for patient engagement. Surgeons reviewed all class I and IIa "2004 American Heart Association/American College of Cardiology Guidelines for CABG Surgery" and translated them into 40 verifiable behaviors. These were imbedded within a new ProvenCareSM program and "hardwired" within the electronic health record system, including order sets, templates, and "time outs". Concurrently preoperative, inpatient, and postoperative care within 90 days was packaged into a fixed price. A Patient Compact was developed to highlight the importance of patient activation. All elective CABG patients treated between February 2, 2006 and February 2, 2007 were included (ProvenCareSM Group) and compared with 137 patients treated in 2005 (Conventional Care Group).

RESULTS

Initially, only 59% of patients received all 40 best practice components. At 3 months, program compliance reached 100%, but fell transiently to 86% over the next 3 months. Reliability subsequently increased to 100% and was sustained for the remainder of the study period. The overall trend in reliability was significant at P=0.001. Thirty-day clinical outcomes showed improved trends () but only the likelihood of discharge to home reached statistical significance. Length of stay decreased by 16% and mean hospital charges fell 5.2%.(Table is included in full-text article.)

CONCLUSION

A provider-driven pay-for-performance process for CABG, enabled by an electronic health record system, can reliably deliver evidence-based care, fundamentally alter reimbursement incentives, and may ultimately improve outcomes and reduce resource use.

Mortality in Medicare beneficiaries following coronary artery bypass graft surgery in states with and without certificate of need regulation

CONTEXT

Certificate of need regulation was designed to control health care costs by preventing health care facilities from expanding unnecessarily. While there have been several studies investigating whether these regulations have affected health care investment, few have evaluated the relationship between certificate of need regulation and quality of care.

OBJECTIVE

To compare risk-adjusted mortality and hospital volumes for coronary artery bypass graft (CABG) surgery in states with and without certificate of need regulation.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of 911 407 Medicare beneficiaries aged 65 years or older, who underwent CABG surgery between 1994 and 1999 in 1063 US hospitals.

MAIN OUTCOME MEASURES

States (and the District of Columbia) with continuous (n = 27), none (n = 18), or intermittent (n = 6) certificate of need regulation; mortality (in-hospital or within 30 days of CABG surgery) rates; and mean annual hospital volumes for CABG surgery.

RESULTS

Unadjusted mortality was 5.1% in states without certificate of need regulation compared with 4.4% in states with continuous regulation, and 4.3% in states with intermittent certificate of need regulation (P<.001 for each comparison). Adjusting for demographic and clinical factors, mortality remained higher in states without certificate of need regulation compared with states with continuous certificate of need regulation (odds ratio [OR], 1.22; 95% confidence interval [CI], 1.15-1.28; P<.001). Using the same groups for comparison, the mean annual hospital volume for CABG surgery was 84% lower in states without certificate of need regulation (104 vs 191; P<.001) and more patients underwent CABG surgery in low-volume hospitals (<100 procedures annually) (30% vs 10% for states with continuous certificate of need programs; P<.001). Following the repeal of certificate of need regulation in states categorized as intermittent, the percentage of patients undergoing CABG surgery in low-volume hospitals tripled.

CONCLUSIONS

Mortality rates for Medicare patients undergoing CABG surgery were higher in states without certificate of need regulation. Repeal of certificate of need regulations during the study period was associated with declines in hospital volume for CABG surgery.

The role of hospital volume in coronary artery bypass grafting: is more always better?

OBJECTIVES

The goal of this study was to determine whether outcomes of nonemergent coronary artery bypass grafting (CABG) differed between low- and high-volume hospitals in patients at different levels of surgical risk.

BACKGROUND

Regionalizing all CABG surgeries from low- to high-volume hospitals could improve surgical outcomes but reduce patient access and choice. "Targeted" regionalization could be a reasonable alternative, however, if subgroups of patients that would clearly benefit from care at high-volume hospitals could be identified.

METHODS

We assessed outcomes of CABG at 56 U.S. hospitals using 1997 administrative and clinical data from Solucient EXPLORE, a national outcomes benchmarking database. Predicted in-hospital mortality rates for subjects were calculated using a logistic regression model, and subjects were classified into five groups based on surgical risk: minimal (< 0.5%), low (0.5% to 2%), moderate (2% to 5%), high (5% to 20%), and severe (> or =20%). We assessed differences in in-hospital mortality, hospital costs and length of stay between low- and high-volume facilities (defined as > or =200 annual cases) in each of the five risk groups.

RESULTS

A total of 2,029 subjects who underwent CABG at 25 low-volume hospitals and 11,615 subjects who underwent CABG at 31 high-volume hospitals were identified. Significant differences in in-hospital mortality were seen between low- and high-volume facilities in subjects at moderate (5.3% vs. 2.2%; p = 0.007) and high risk (22.6% vs. 11.9%; p = 0.0026) but not in those at minimal, low or severe risk. Hospital costs and lengths of stay were similar across each of the five risk groups. Based on these results, targeted regionalization of subjects at moderate risk or higher to high-volume hospitals would have resulted in an estimated 370 transfers and avoided 16 deaths; in contrast, full regionalization would have led to 2,029 transfers and avoided 20 deaths.

CONCLUSIONS

Targeted regionalization might be a feasible strategy for balancing the clinical benefits of regionalization with patients' desires for choice and access.

Cost-effectiveness of targeting patients undergoing cardiac surgery for therapy with intravenous amiodarone to prevent atrial fibrillation

OBJECTIVES

This study evaluated the cost-effectiveness of administering prophylactic intravenous (IV) amiodarone therapy to patients undergoing cardiac surgery according to their predicted risk of postoperative atrial fibrillation.

BACKGROUND

Atrial fibrillation (AF) is a common complication of cardiovascular surgery that is associated with a significant increase in hospitalization costs. Intravenous amiodarone has been shown to decrease the incidence of postoperative AF.

METHODS

All 8,709 patients who underwent coronary artery bypass grafting (CABG), 1,217 patients who underwent valve replacement and 624 patients who underwent CABG and valve replacement procedures (CABG + valve) from January 1, 1994, to June 30, 1999, at Emory University Hospitals were studied. Models predicting the risk of AF were developed using logistic regression; linear regression was used to estimate the influence of AF on hospitalization costs. Cost-effectiveness was evaluated for patient subsets identified according to their predicted risk of AF.

RESULTS

Postoperative AF rates were 17.7% for CABG, 24.6% for valve and 33.8% for CABG + valve. Using 5,000 dollars as an acceptable cost per episode of atrial fibrillation averted, prophylactic IV amiodarone in CABG patients was not found to be cost-effective. Therapy would be recommended for roughly 5% of valve patients with a predicted risk of atrial fibrillation >45%, and roughly two thirds of CABG + valve patients who have a predicted risk of >30%.

CONCLUSIONS

Cost-effectiveness of prophylactic IV amiodarone varies according to type of surgery and the predicted risk of atrial fibrillation. Older patients undergoing valve replacement, particularly those with a history of chronic obstructive pulmonary disease, and those undergoing concomitant CABG are likely to be the most appropriate candidates for IV amiodarone therapy in the perioperative period.

A multivariable model for predicting the need for blood transfusion in patients undergoing first-time elective coronary bypass graft surgery

BACKGROUND

The incidence of blood transfusion in coronary artery bypass graft (CABG) surgery remains high. Preoperative identification of those at high risk for requiring blood will allow for the cost-effective use of some blood conservation modalities. Multivariable analysis techniques were used in this study to develop a prediction rule for such a purpose.

STUDY DESIGN AND METHODS

Data were prospectively collected for all patients undergoing elective first-time CABG surgery from January 1997 to September 1998 at a tertiary-care teaching hospital (n = 1007). The prediction rule was developed on the first two-thirds of the sample by using logistic regression methods to examine the relationship of patient demographics, comorbidities, and preoperative Hb with perioperative blood transfusion. The remaining one-third of the sample was used to validate the rule.

RESULTS

The transfusion rate was 29.4 percent. The prediction rule included preoperative Hb (g/dL, OR 0.928, p<0.0001), weight (kg, OR 0.938, p<0.0001), age (years, OR 1.037, p<0.01), and sex (male/female, OR 0.493, p<0.01); receiver operating characteristic = 0.86. When externally validated, the rule had a sensitivity of 82.1 percent and a specificity of 63.6 percent (at a selected probability cutoff).

CONCLUSION

A simple and valid prediction rule is developed for predicting the risk of blood transfusion in patients undergoing first-time elective CABG surgery.

Proliferation of Cardiac Technology in Canada

Background— Critics remain skeptical about the long-term sustainability of Medicare in Canada because of the proliferation of health technology and escalating expenditures. The objective of this study was to examine the temporal trends in the utilization and costs of cardiovascular technologies for the evaluation and/or management of patients with ischemic heart disease in Canada.

Methods and Results— This repeated cross-sectional population-based study of Ontario residents examined the temporal trends in the utilization and costs associated with echocardiography, stress (imaging and nonimaging) testing, coronary angiography, percutaneous coronary intervention (PCI), and bypass surgery between 1992 and 2001. Annual costs increased by nearly 2-fold over the 10-year study period and cumulatively accounted for more than $2.8 billion (Canadian) in expenditures. The proliferation in use of cardiac testing/interventions over time outstripped both demographic shifts and changes in the prevalence of coronary artery disease. Annual increases were widespread for all procedures ( P <0.001) and ranged from 2% per year for nonimaging stress tests to 12% per year for PCI, after adjustment for age and sex. Generally, utilization rates were higher among the elderly, males, and those of low socioeconomic status. With few exceptions, annual increases in the utilization rates of cardiac tests and procedures were disproportionately higher among the elderly and women, but they were similar across socioeconomic subgroups. Increases in utilization appeared to reflect referrals toward higher-risk populations.

Conclusions— Although definitive conclusions about the appropriateness of temporal patterns cannot be ascertained, the proliferation of cardiac testing challenges the sustainability of Medicare in Canada, especially given uncertainty as to whether the accompanying incremental rise in total expenditures translates into significant outcome benefits in the population.

Comparison of analytic models for estimating the effect of clinical factors on the cost of coronary artery bypass graft surgery

The cost of treating disease depends on patient characteristics, but standard tools for analyzing the clinical predictors of cost have deficiencies. To explore whether survival analysis techniques might overcome some of these deficiencies in the analysis of cost data, we compared ordinary least square (OLS) linear regression (with and without transformation of the data) and binary logistic regression with two survival models: the Cox proportional hazards model and a parametric model assuming a Weibull distribution. Each model was applied to data from 155 patients undergoing coronary artery bypass grafting. We examined the effects of age, sex, ejection fraction, unstable angina, and number of diseased vessels on univariable and multivariable predictions of costs. The significant univariable predictors of cost were consistent in all models: ejection fraction was significant in all five models, and age and number of diseased vessels were each significant in all but the OLS model, while sex and angina type were significant in none of the models. The significant multivariable predictors of cost, however, differed according to model: ejection fraction was a significant multivariable predictor of cost in all five models, age was significant in three models, and number of diseased vessels was significant in one model. All five models were also used to predict the costs for an average patient undergoing surgery. The Cox model provided the most accurate predictions of mean cost, median cost, and the proportion of patients with high cost. This study shows: (1) lower ejection fraction and older age are independent clinical predictors of increased cost of CABG, and (2) the Cox proportional hazards model shows considerable promise for the analysis of the impact of clinical factors upon cost.

Incremental Cost of Emergency Versus Elective Surgery

OBJECTIVE

To determine hospital costs and the adjusted risk of death associated with emergent versus elective surgery.

BACKGROUND

Emergency surgery has a higher cost and worse outcomes compared with elective surgery. However, no national estimates of the excess burden of emergency surgery exist.

METHODS

Nationwide Inpatient Sample (NIS) data from 2001 to 2010 were analyzed. Patients aged 18 years or older who underwent abdominal aortic aneurysm repair, coronary artery bypass graft, or colon resection for neoplasm were included. Using generalized linear models with propensity scores, cost differences for emergent versus elective admission were calculated for each procedure. Multivariable logistic regression was performed to investigate the adjusted odds of mortality comparing elective and emergent cases. Discharge-level weights were applied to analyses.

RESULTS

A total of 621,925 patients, representing a weighted population of 3,057,443, were included. The adjusted mean cost difference for emergent versus elective care was $8741.22 (30% increase) for abdominal aortic aneurysm repair, $5309.78 (17% increase) for coronary artery bypass graft, and $7813.53 (53% increase) for colon resection. If 10% of the weighted estimates of emergency procedures had been performed electively, the cost benefit would have been nearly $1 billion, at $996,169,160 (95% confidence interval [CI], $985,505,565-$1,006,834,104). Elective surgery patients had significantly lower adjusted odds of mortality for all procedures.

CONCLUSIONS

Even a modest reduction in the proportion of emergent procedures for 3 conditions is estimated to save nearly $1 billion over 10 years. Preventing emergency surgery through improved care coordination and screening offers a tremendous opportunity to save lives and decrease costs.

Medical Costs and Quality of Life 10 to 12 Years After Randomization to Angioplasty or Bypass Surgery for Multivessel Coronary Artery Disease

BACKGROUND

Coronary bypass surgery (CABG) and angioplasty (PTCA) have been compared in several randomized trials, but data about long-term economic and quality-of-life outcomes are limited.

METHODS AND RESULTS

Cost and quality-of-life data were collected prospectively from 934 patients who were randomized in the Bypass Angioplasty Revascularization Investigation (BARI) and followed up for 10 to 12 years. CABG had 53% higher costs initially, but the gap closed to <5% during the first 2 years; after 12 years, the mean cumulative cost of CABG patients was 123,000 dollars versus 120,750 dollars for PTCA, yielding a cost-effectiveness ratio of 14,300 dollars/life-year added. CABG patients experienced significantly greater improvement in their physical functioning for the first 3 years but not in later follow-up. Recurrent angina substantially reduced all quality-of-life measures throughout follow-up. Cumulative costs were significantly higher among patients with diabetes, heart failure, and comorbid conditions and among women; costs also were increased by angina, by the number of revascularization procedures, and among patients who died.

CONCLUSIONS

Early differences between CABG and PTCA in costs and quality of life were no longer significant at 10 to 12 years of follow-up. CABG was cost-effective as compared with PTCA for multivessel disease.

Is percutaneous coronary angioplasty less expensive than bypass surgery?

Percutaneous transluminal coronary angioplasty is widely considered to be an acceptable and less expensive alternative to bypass surgery in carefully selected patients. We compared expenditures related to cardiac care for 79 unselected patients undergoing coronary angioplasty with expenditures for 89 unselected patients undergoing elective coronary bypass surgery without a previous attempt at angioplasty. All the patients had single-vessel disease. The mean aggregate one-year monetary outlay was 15 per cent lower in the angioplasty group than in the bypass-surgery group. A major component of the expense of angioplasty was the treatment of restenosis in the 33 per cent of patients in this group in whom this late complication occurred. We conclude that percutaneous transluminal coronary angioplasty has potential for reducing expenditures for cardiac revascularization and that a further reduction may be obtainable when the rates of restenosis are improved.