Echocardiographic risk stratification for early surgery with endocarditis: a cost-effectiveness analysis

BACKGROUND

Despite widespread acceptance of echocardiography for diagnosis of infective endocarditis, few investigators have evaluated its utility as a risk-stratification tool to aid therapeutic decision-making.

METHODS

A decision tree and Markov analysis model were constructed using published and institutional data to estimate the cost-effectiveness of an echocardiographic risk-stratification strategy for infective endocarditis. The models compared surgery for high-risk patients based on clinical factors ("standard care") and surgery for high-risk patients based on echocardiographic findings ("echocardiography-guided").

RESULTS

The cost per patient for standard care and echocardiography-guided strategies was $47,766 and $53,669, respectively. The expected quality-adjusted life years (QALY) for standard care and echocardiography-guided strategies were 5.86 years and 6.10 years, respectively. Compared with standard care, the echocardiography-guided strategy cost an additional $23,867 per QALY saved. In one-way sensitivity analyses, the incremental cost of this strategy remained <$50,000/QALY across a broad range of scenarios. Baseline stroke risk had the greatest effect on cost-effectiveness. For populations with stroke risk less than 3.65%, the echocardiography-guided strategy was not cost-attractive (ICER >$50,000/QALY). At stroke risk between 3.65% and 14%, the ICER for the echocardiography-guided strategy was attractive (<$50,000 /QALY). The echocardiography-guided strategy became economically dominant at any baseline stroke risk greater than 18.3%.

CONCLUSION

Echo-guided risk stratification for early surgery in patients with large vegetations is a cost-attractive treatment strategy for IE, as it improves outcome for an incremental cost <$50,000/QALY.

Long-term costs and resource use in elderly participants with congestive heart failure in the Cardiovascular Health Study

BACKGROUND

Although heart failure (HF) afflicts nearly 5 million Americans, the long-term cost of HF care has not been described previously. In a prospective, longitudinal cohort of community-dwelling elderly from 4 regions, we examined the long-term costs and resource use of elderly patients with HF.

METHODS

We linked 4860 elderly participants in the National Heart, Lung, and Blood Institute Cardiovascular Health Study to Medicare part A and part B claims from 1992 to 2003. Costs were calculated from Medicare payments and discounted at 3% annually. We applied nonparametric estimators to calculate mean costs and resource use per patient for a 10-year period. To describe the relationship between patient characteristics and long-term costs, we constructed censoring-adjusted regression models.

RESULTS

There were 343 participants (84.8% white; 50.1% men; mean age, 78.2 years) with prevalent HF and 4517 participants without HF at study entry. Mean follow-up was 6.7 years (median, 6.4 years). The 10-year survival rates were 33% and 63% for the prevalent HF and nonprevalent HF groups (P < .001), respectively. The mean 10-year medical costs were significantly higher for the prevalent HF cohort (54,704 dollars vs 41 dollars,780, P < .001). The higher costs associated with HF were also reflected in greater resource use with more hospitalizations (P < .05) and more intensive care unit days (P < .05). Participants with HF had more physician visits (P < .05), with most of these encounters involving noncardiology physicians. However, in multivariate models, prevalent HF was not an independent predictor of higher costs.

CONCLUSION

Patients with HF consume substantially more health care resources than their elderly peers, and these higher costs persist through 10 years of follow-up. Many of these costs may be related to other comorbid conditions.

Reperfusion of acute myocardial infarction in North Carolina emergency departments (RACE): study design

Despite the accumulation of almost 2 decades of data in support of rapid reperfusion therapy for ST-segment elevation myocardial infarction (STEMI), the United States healthcare system still faces serious challenges in providing reperfusion to all eligible patients in a timely fashion. American College of Cardiology/American Heart Association guidelines call for systematic interventions aimed at improving both the proportion of patients receiving reperfusion and the timeliness of treatment. We designed a project (RACE) that incorporates standardized protocols and integrated systems for treatment and timely transfer (when appropriate) of patients with STEMI in 5 geographic regions in North Carolina. The RACE project was created by an alliance between national and regional professional societies, a local payer, the pharmaceutical, and healthcare providers, including emergency medical services, emergency medicine, cardiology, and hospital administrations. The main outcomes of interest are rates of reperfusion and time to treatment. Collected data will also provide important insights into barriers to timely reperfusion. The goal of the RACE project is to provide a model for improving the care of patients with STEMI by identifying those features associated with significant improvement, as well as those imposing significant barriers to appropriate therapy.

Temporal trends in target vessel revascularization in clinical practice: long-term outcomes following coronary stenting from the Duke Database for Cardiovascular Disease

OBJECTIVE

We examined outcomes of clinical restenosis and temporal trends in repeat target vessel revascularization (TVR) among a broad, unselected patient population undergoing percutaneous coronary revascularization.

BACKGROUND

The extent to which clinical trials involving protocol-specified follow-up angiography reflect real-world practice where interventions are driven by clinical restenosis is not completely understood. Whether clinical outcomes have varied over a long-term period that has paralleled substantial advances in stent design, balloon delivery catheter and adjunctive pharmacologic therapies is uncertain.

METHODS

To characterize the effectiveness of coronary stenting in routine practice, we examined 1-year clinical outcomes of death and repeat TVR among 5,765 patients enrolled in the Duke Database for Cardiovascular Disease who underwent stent placement between 1994 and 2002. To assess for temporal trends in outcomes, patients were further divided into tertiles according to the year of initial revascularization.

RESULTS

Overall, the 1-year occurrence of TVR and death was 11.4% and 4.9%, respectively. Rates of repeat TVR increased at 3-month intervals, with most events occurring prior to 9 months. In an adjusted analysis over an 8-year period, 1-year survival did not significantly differ across patient tertiles (p = 0.95), although rates of recurrent TVR significantly decreased (1994-1996, 11.1%; 1997-1999, 11.5%; 2000-2002, 9.3%; p = 0.003).

CONCLUSIONS

In a broad patient population in whom repeat angiography is not protocol-specified, most events occur within the initial months following revascularization, yet late clinical restenosis continues. Although survival has not improved since the introduction of coronary stents, overall rates of repeat revascularization have modestly, but significantly, declined.

Predicting significant coronary artery disease in patients with left ventricular dysfunction

BACKGROUND

Because coronary artery disease (CAD) is a prevalent comorbidity in patients with low ejection function (EF), a number of patients with heart failure undergo diagnostic cardiac catheterization. The objective of this study was to develop a model to assist clinicians in determining the likelihood of CAD before cardiac catheterization.

METHODS

This study was a retrospective analysis using the Duke Databank for Cardiovascular Disease. From the databank, 2054 patients who underwent cardiac catheterization between 1992 and 2002 that was preceded by echocardiography with an EF of < 45% were identified. The patients' median age was 63 years, and the median EF was 30%. Patients were considered to have significant CAD if any major epicardial vessel had > or = 75% stenosis. A multivariable model of CAD was generated using stepwise logistic regression. We included demographic, clinical, electrocardiographic, and echocardiographic parameters, including segmental wall motion abnormality.

RESULTS

Of the patients who met the criteria, 1184 (58%) had significant CAD and 870 (42%) did not. Significant predictors of CAD, in the order of their ability to predict significant CAD, included history of myocardial infarction, age, diabetes mellitus, Q wave on electrocardiogram, male sex, and segmental wall motion abnormality (all P < .0001). The area under the receiver operating characteristic curve was 0.865.

CONCLUSIONS

By using baseline demographic and clinical characteristics, we developed a highly discriminatory diagnostic model for predicting CAD in patients with heart failure. Given the high prevalence of patients without CAD in this cohort, accurate baseline assessment of patients with left ventricular dysfunction for CAD might avoid unnecessary invasive procedures.

Comparison of long-term (seven year) outcomes among patients undergoing percutaneous coronary revascularization with versus without stenting

Coronary stents have markedly improved the short- and intermediate-term safety and efficacy of percutaneous coronary intervention by improving acute gains in luminal dimensions, decreasing abrupt vessel occlusion, and decreasing restenosis, yet the long-term benefit of coronary stenting remains uncertain. We examined long-term clinical outcomes of death, myocardial infarction, and repeat target vessel revascularization (TVR) among patients enrolled in the Duke Database for Cardiovascular Disease who underwent revascularization with percutaneous transluminal coronary angioplasty alone or stent placement from 1990 to 2002. Among 6,956 patients who underwent percutaneous revascularization, propensity modeling was applied to identify 1,288 matched patients with a similar likelihood to receive coronary stents according to clinical, angiographic, and demographic characteristics. Significant (p <0.05) predictors of stent placement included multivessel disease, diabetes, hypertension, recent myocardial infarction, decreased ejection fraction, and year of study entry. At a median follow-up of 7 years, although treatment with coronary stenting was associated with a significant and sustained decrease in repeat TVR (18.0% vs 28.1%, p = 0.0002) and the occurrence of death, myocardial infarction or TVR (39.2% vs 45.8%, p = 0.004), long-term survival did not significantly differ between treatment groups (19.9% vs 20.5%, p = 0.72). Outcomes of death and myocardial infarction did not significantly differ between patients who did and did not undergo repeat TVR. In conclusion, compared with angioplasty alone, revascularization with coronary stents provides a significant early and sustained decrease in the need for repeat revascularization, but stents do not influence long-term survival.

Transesophageal assessment of left atrial thrombus using a 3.3-mm monoplane probe

OBJECTIVES

Our study was designed to demonstrate that transesophageal echocardiography using a 3.3-mm monoplane probe can accurately evaluate the left atrium for patients with arrhythmias before cardioversion.

BACKGROUND

Standard probes cause discomfort during intubation requiring sedation, but miniature probes do not.

METHODS

With topical anesthesia alone, a 3.3-mm probe was used for transesophageal echocardiography in 60 patients. After intravenous sedation, standard transesophageal echocardiography was then performed.

RESULTS

In 51 of 60 patients, the left atrium was visualized with the 3.3-mm probe. In 43 of 51 patients the appendage was clear. A thrombus was seen in 7 patients on both studies. In one patient spontaneous echocontrast was seen only with the 3.3-mm probe (sensitivity 100%, specificity 97%). In 9 of 60 patients, the appendage could not be assessed.

CONCLUSIONS

In many patients the 3.3-mm probe can visualize the appendage and obviate the need for sedation. Technical advances will improve image quality with miniature probes.

Costs for Heart Failure With Normal vs Reduced Ejection Fraction

BACKGROUND

Among the elderly population, heart failure (HF) with normal ejection fraction (EF) is more common than classic HF with low EF. However, there are few data regarding the costs of HF with normal EF. In a prospective, population-based cohort of elderly participants, we compared the costs and resource use of patients with HF and normal and reduced EF.

METHODS

A total of 4549 participants (84.5% white; 40.6% male) in the National Heart, Lung, and Blood Institute Cardiovascular Health Study were linked to Medicare claims from 1992 through 1998. By protocol echo examinations or clinical EF assessments, 881 participants with HF were characterized as having abnormal or normal EF. We applied semiparametric estimators to calculate mean costs per subject for a 5-year period.

RESULTS

There were 495 HF participants with normal EF (186 prevalent at study entry and 309 incident during the study period) and 386 participants with abnormal EF (166 prevalent and 220 incident). Participants with abnormal EF had more cardiology encounters and cardiac procedures. However, compared with abnormal EF participants, the 5-year costs for normal EF participants were similar in both the prevalent ($33,023 with abnormal EF and $32,580 with normal EF; P=.93) and incident ($49,128 with abnormal EF and $45,604 with normal EF; P=.55) groups. In models accounting for comorbid conditions, the costs with normal and abnormal EF remained similar.

CONCLUSIONS

Over a 5-year period, patients with HF and normal EF consume as many health care resources as those with reduced EF. These data highlight the substantial financial burden of HF with normal EF among the elderly population.

The relation between patients' outcomes and the volume of cardioverter-defibrillator implantation procedures performed by physicians treating Medicare beneficiaries

OBJECTIVES

The purpose of this study is to determine if implantable cardioverter-defibrillator (ICD) implantation should be limited to physicians with high procedural volume.

BACKGROUND

Expanding indications for ICDs will result in an increasing number of physicians implanting these devices.

METHODS

Using the 20% Part B Medicare files for 1999 through 2001, we identified new ICD implantations and the corresponding denominator files. We used Medicare Provider Analysis and Review hospital records and the appropriate International Classification of Diseases-9 diagnosis and procedure codes to define complications within 90 days. We defined physician volume categories by assigning one-quarter of the patients to each quartile. A logistic regression model was used to adjust outcomes for potential confounders.

RESULTS

Ninety-day mortality did not differ between patients who had their ICD implanted by physicians with the highest volume of implants and those who had their ICD implanted by physicians with the lowest volume of implants (6.2% vs. 5.9%; odds ratio [OR] 0.99; 95% confidence interval [CI] 0.75 to 1.30). Within 90 days, mechanical complications were significantly higher in the lowest volume quartile (OR 1.47; 95% CI 1.09 to 1.99) but were comparable for physicians who implanted at least 11 ICDs per year. The risk of ICD infection was significantly higher in patients who had their ICD implanted by physicians with the lowest volume of implants (OR 2.47; 95% CI 1.18 to 5.17).

CONCLUSIONS

We observed an association between a higher volume of ICD implants and a lower rate of mechanical complications and infections. This association suggests that ICD implantation should not be performed by physicians without regard to their procedural volume.

Evidence-based therapies and mortality in patients hospitalized in December with acute myocardial infarction

BACKGROUND

Previous studies suggest that patients hospitalized with acute myocardial infarction (MI) in December have poor outcomes, and some studies have hypothesized that the cause may be the infrequent use of evidence-based therapies during the December holiday season.

OBJECTIVE

To compare the care and outcomes of patients with acute MI hospitalized in December and patients hospitalized during other months.

DESIGN

Retrospective analysis of data from the Cooperative Cardiovascular Project.

SETTING

Nonfederal, acute care hospitals in the United States.

PATIENTS

127 959 Medicare beneficiaries hospitalized between January 1994 and February 1996 with confirmed acute MI.

MEASUREMENTS

Use of aspirin, beta-blockers, and reperfusion therapy (thrombolytic therapy or percutaneous coronary intervention), and 30-day mortality.

RESULTS

When the authors controlled for patient, hospital, and physician characteristics, the use of evidence-based therapies was not significantly lower but 30-day mortality was higher (21.7% vs. 20.1%; adjusted odds ratio, 1.07 [95% CI, 1.02 to 1.12]) among patients hospitalized in December.

LIMITATIONS

This was a nonrandomized, observational study. Unmeasured characteristics may have contributed to outcome differences.

CONCLUSIONS

Thirty-day mortality rates were higher for Medicare patients hospitalized with acute MI in December than in other months, although the use of evidence-based therapies was not significantly lower.

The significance of elevated troponin T in patients with nondialysis-dependent renal insufficiency: a validation with coronary angiography

BACKGROUND

Patients with elevated troponin are at high risk of adverse outcomes, future cardiac events, and are more likely to have hemodynamically significant coronary artery stenoses. Elevated troponin T (cTnT) in patients with poor renal function portends a poor prognosis; however, findings of significant coronary artery disease (CAD) by coronary angiography have not been demonstrated in patients with poor renal function and elevated cTnT.

HYPOTHESIS

The purpose of this study was to correlate the angiographic findings of patients with elevated cTnT with respect to renal function in patients with nondialysis-dependent renal insufficiency.

METHODS

We retrospectively identified 342 patients with elevated cTnT who underwent coronary angiography in the setting of acute coronary syndrome. Patients were divided into poor (< 40 ml/min) and normal (> 40 ml/min) renal function by measuring their glomerular filtration rate. Our primary outcome was CAD stenosis, defined as epicardial stenosis > or = 70%. Secondary outcomes were rates of contrast nephropathy, initiation of hemodialysis, revascularization, length of stay (LOS), and in-hospital mortality.

RESULTS

There was no significant difference in the prevalence of CAD between patients who had positive cTnT with poor renal function versus patients with positive cTnT and normal renal function (87.1 vs. 89.7%, p = 0.54). This finding persisted after stratifying by age. Patients with impaired renal function had a higher mortality, longer LOS, and a higher rate contrast nephropathy requiring hemodialysis.

CONCLUSION

The association between elevated cTnT and significant CAD stenosis does not vary with renal function.

Clinical and economic implications of the Multicenter Automatic Defibrillator Implantation Trial-II

BACKGROUND

The Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II demonstrated that implantable cardioverter defibrillators (ICDs) save lives when used in patients with a history of myocardial infarction (MI) and an ejection fraction of 0.3 or less.

OBJECTIVE

To investigate the cost-effectiveness of implanting ICDs in patients who met MADIT-II eligibility criteria and were enrolled in the Duke Cardiovascular Database between 1 January 1986 and 31 December 2001.

DESIGN

Cost-effectiveness analysis.

DATA SOURCES

Published literature, databases owned by Duke University Medical Center, and Medicare data.

TARGET POPULATION

Adults with a history of MI and an ejection fraction of 0.3 or less.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTIONS

ICD therapy versus conventional medical therapy.

OUTCOMES MEASURES

Cost per life-year gained and incremental cost-effectiveness.

RESULTS

Compared with conventional medical therapy, ICDs are projected to result in an increase of 1.80 discounted years in life expectancy and an incremental cost-effectiveness ratio of 50,500 dollars per life-year gained. Cost-effectiveness varied dramatically with changes in time horizon: The cost-effectiveness ratio increased to 67,800 dollars per life-year gained, 79,900 dollars per life-year gained, 100,000 dollars per life-year gained, 167,900 dollars per life-year gained, and 367,200 dollars per life-year gained for 15-year, 12-year, 9-year, 6-year, and 3-year time horizons, respectively. Changing the frequency of follow-up visits, complication rates, and battery replacements had less of an effect on the cost-effectiveness ratios than reducing the cost of ICD placement and leads.

LIMITATIONS

The study was limited by the completeness of the data, referral bias, difference in medical therapy between the Duke cohort and the MADIT-II cohort, and not addressing potential upgrades to biventricular devices.

CONCLUSIONS

The economic expense of defibrillator implantation in all patients who meet MADIT-II eligibility criteria is substantial. However, in the range of survival benefit observed in MADIT-II, ICD therapy for these patients is economically attractive by conventional standards.

Dollars and Stents: The Economics of Drug-Eluting Stents

By averting restenoses, drug-eluting stents (DES) reduce the need for repeat revascularization procedures and improve quality of life. Large, randomized clinical trials including the Sirolimus-Eluting Balloon Expandable Stent in Treatment of Patients With De Novo Native Coronary Artery Lesions (SIRIUS) suggest that DES may be cost-effective to the Medicare system over time. However, the high cost of DES and the loss of revenues from revascularization procedures coupled with inadequate Medicare reimbursement are likely to have adverse effects on hospitals, making it hard to meet their bottom line. Key contributors to this problem include the unequal distribution of Medicare reimbursement based on diagnosis-related groups or diagnosis-related group calculations and the lack of price competition for DES. The economic burden of restenoses, the efficacy of DES in averting restenoses, the cost-effectiveness of DES, and the interaction of Medicare, DES manufacturers, and hospitals are reviewed. Using specific cost-containment strategies, hospitals can better maneuver the financial barriers to optimize DES utilization.

Relationship of blood transfusion and clinical outcomes in patients with acute coronary syndromes

CONTEXT

It is unclear if blood transfusion in anemic patients with acute coronary syndromes is associated with improved survival.

OBJECTIVE

To determine the association between blood transfusion and mortality among patients with acute coronary syndromes who develop bleeding, anemia, or both during their hospital course.

DESIGN, SETTING, AND PATIENTS

We analyzed 24,112 enrollees in 3 large international trials of patients with acute coronary syndromes (the GUSTO IIb, PURSUIT, and PARAGON B trials). Patients were grouped according to whether they received a blood transfusion during the hospitalization. The association between transfusion and outcome was assessed using Cox proportional hazards modeling that incorporated transfusion as a time-dependent covariate and the propensity to receive blood, and a landmark analysis.

MAIN OUTCOME MEASURE

Thirty-day mortality.

RESULTS

Of the patients included, 2401 (10.0%) underwent at least 1 blood transfusion during their hospitalization. Patients who underwent transfusion were older and had more comorbid illness at presentation and also had a significantly higher unadjusted rate of 30-day death (8.00% vs 3.08%; P<.001), myocardial infarction (MI) (25.16% vs 8.16%; P<.001), and death/MI (29.24% vs 10.02%; P<.001) compared with patients who did not undergo transfusion. Using Cox proportional hazards modeling that incorporated transfusion as a time-dependent covariate, transfusion was associated with an increased hazard for 30-day death (adjusted hazard ratio [HR], 3.94; 95% confidence interval [CI], 3.26-4.75) and 30-day death/MI (HR, 2.92; 95% CI, 2.55-3.35). In the landmark analysis that included procedures and bleeding events, transfusion was associated with a trend toward increased mortality. The predicted probability of 30-day death was higher with transfusion at nadir hematocrit values above 25%.

CONCLUSIONS

Blood transfusion in the setting of acute coronary syndromes is associated with higher mortality, and this relationship persists after adjustment for other predictive factors and timing of events. Given the limitations of post hoc analysis of clinical trials data, a randomized trial of transfusion strategies is warranted to resolve the disparity in results between our study and other observational studies. We suggest caution regarding the routine use of blood transfusion to maintain arbitrary hematocrit levels in stable patients with ischemic heart disease.

State-mandated continuing medical education and the use of proven therapies in patients with an acute myocardial infarction

OBJECTIVES

The purpose of this study was to determine whether state-mandated continuing medical education (CME) requirements affect the use of evidence-based therapies and outcomes in patients with acute myocardial infarction (AMI).

BACKGROUND

The Institute of Medicine recommends that educational programs demonstrate their effect through process and outcome measures.

METHODS

We analyzed 134,609 patients according to whether or not CME was mandated in the state of physician practice. A hierarchical multivariable model was developed that controlled for state, hospital, physician, and patient level characteristics to determine the association between state CME requirements and the use of evidence-based therapies. Primary outcome measures were admission aspirin use and reperfusion therapy, and discharge aspirin and beta-blocker prescription. Thirty-day and one-year mortality were secondary outcome measures.

RESULTS

States with and without CME requirements had similar rates of aspirin use at admission and discharge (79.9% vs. 79.4% and 72.5% vs. 72.5%, respectively) and beta-blocker prescription at discharge (53.6% vs. 55.3%). The rate of reperfusion therapy at admission was significantly higher in states requiring CME (53.1%) compared with states without CME (47.9%) (p < 0.0001). After adjustment, patients admitted in CME-requiring states were significantly more likely to receive reperfusion therapy, mainly owing to "patented" thrombolytic therapy (odds ratio 1.15; p = 0.016). There was no association between CME requirements and one-year mortality.

CONCLUSIONS

State-mandated CME had little association with AMI care or outcome, other than an increased use of patented thrombolytic therapy. Further research is needed to maximize the measurable effect of CME on the use of proven therapies irrespective of whether patented or generic medications are involved.

Socioeconomic status and outcome following acute myocardial infarction in elderly patients

BACKGROUND

Although the Medicare entitlement provides universal hospital care coverage for elderly Americans, disparities in care processes after acute myocardial infarction still exist. Whether these disparities account for increased mortality among elderly poor patients is not known.

METHODS

To determine the association between socioeconomic status and acute myocardial infarction treatment, procedure use, and 30-day and 1-year mortality, we analyzed data from 132 130 elderly Medicare beneficiaries hospitalized for acute myocardial infarction between January 1994 and February 1996. Patients were categorized into 10 groups of increasing income using the median income of the ZIP code of residence.

RESULTS

The highest-income beneficiaries received higher rates of evidence-based medical therapy and had lower adjusted 30-day and 1-year mortality rates compared with the middle-income beneficiaries (30-day relative risk, 0.89 [95% confidence interval, 0.85-0.94]; and 1-year relative risk, 0.92 [95% confidence interval, 0.88-0.97]). Conversely, the lowest-income beneficiaries received lower rates of evidence-based medical treatment and had higher adjusted 30-day and 1-year mortality rates relative to the middle-income beneficiaries (30-day relative risk, 1.09 [95% confidence interval, 1.04-1.13]; and 1-year relative risk, 1.05 [95% confidence interval, 1.00-1.10]). Coronary revascularization rates were similar among income groups.

CONCLUSIONS

Despite the Medicare entitlement, there remain significant socioeconomic disparities in medical treatment and mortality among elderly patients following acute myocardial infarction. Income was independently associated with short- and long-term mortality. More research is required to determine the mechanisms contributing to adverse outcomes among poor elderly patients and to determine whether expansion of Medicare coverage will alleviate these disparities.

Usefulness of myocardial viability or ischemia in predicting long-term survival for patients with severe left ventricular dysfunction undergoing revascularization

In 107 patients with coronary disease and severe left ventricular dysfunction, we examined the prognostic power of viability identified by dobutamine stress echocardiography. At a mean follow-up of 27 months, patients with viable myocardium who underwent revascularization had a significant survival advantage over all other patients (2-year survival 83.5% vs 57.2%, p = 0.0037).

Impact of managed care on the treatment, costs, and outcomes of fee-for-service Medicare patients with acute myocardial infarction

OBJECTIVE

To examine the effects of market-level managed care activity on the treatment, cost, and outcomes of care for Medicare fee-for-service acute myocardial infarction (AMI) patients.

DATA SOURCES/STUDY SETTING

Patients from the Cooperative Cardiovascular Project (CCP), a sample of Medicare beneficiaries discharged from nonfederal acute-care hospitals with a primary discharge diagnosis of AMI from January 1994 to February 1996.

STUDY DESIGN

We estimated models of patient treatment, costs, and outcomes using ordinary least squares and logistic regression. The independent variables of primary interest were market-area managed care penetration and competition. The models included controls for patient, hospital, and other market area characteristics.

DATA COLLECTION/EXTRACTION METHODS

We merged the CCP data with Medicare claims and other data sources. The study sample included CCP patients aged 65 and older who were admitted during 1994 and 1995 with a confirmed AMI to a nonrural hospital.

PRINCIPAL FINDINGS

Rates of revascularization and cardiac catheterization for Medicare fee-for-service patients with AMI are lower in high-HMO penetration markets than in low-penetration ones. Patients admitted in high-HMO-competition markets, in contrast, are more likely to receive cardiac catheterization for treatment of their AMI and had higher treatment costs than those admitted in low-competition markets.

CONCLUSIONS

The level of managed care activity in the health care market affects the process of care for Medicare fee-for-service AMI patients. Spillovers from managed care activity to patients with other types of insurance are more likely when managed care organizations have greater market power.

Prognostic usefulness of left ventricular thrombus by echocardiography in dilated cardiomyopathy in predicting stroke, transient ischemic attack, and death

Echocardiograms of 290 patients with dilated cardiomyopathy (ejection fraction < or =35%) were reviewed for the presence of left ventricular (LV) apical abnormalities; outcomes of stroke and death were then correlated with the presence of LV thrombus. During a follow-up of 31 months, 15 patients had a stroke or transient ischemic attack after the index echocardiogram (5.2%). Patients with LV thrombus on echocardiography had a significantly higher rate of stroke (adjusted odds ratio 3.4, p = 0.027) than those without echocardiographic evidence of thrombi. There was no difference in mortality between patients with and without thrombus (20.9% vs 21.1%, p = 0.726).

The prognostic importance of comorbidity for mortality in patients with stable coronary artery disease

OBJECTIVES

To identify the prevalent and prognostically important coexisting illnesses among single coronary artery disease (CAD) patients.

BACKGROUND

As the population ages, physicians are increasingly required to make decisions concerning patients with multiple co-existing illnesses (comorbidity). Many trials of CAD therapy have excluded patients with significant comorbidity, such that there are limited data to guide the management of those patients.

METHODS

To consider the long-term prognostic importance of comorbid illness, we examined a cohort of 1471 patients with CAD who underwent cardiac catheterization between 1985 and 1989 and were followed up through 2000 in the Duke Databank for Cardiovascular Diseases. Weights were assigned to individual diseases according to their prognostic significance in Cox proportional hazards models, thus creating a new CAD-specific index. The new index was compared with the widely used Charlson index, according to prevalence of conditions, individual and overall associations with survival, and agreement.

RESULTS

The Charlson index and the CAD-specific index were highly associated with long-term survival and almost equivalent to left ventricular ejection fraction. When considering the components of the Charlson index, diabetes, renal insufficiency, chronic obstructive pulmonary disease, and peripheral vascular disease had greater prognostic significance among CAD patients, whereas peptic ulcer disease, connective tissue disease, and lymphoma were less significant. Hemiplegia, leukemia, lymphoma, severe liver disease, and acquired immunodeficiency syndrome were rarely identified among patients undergoing coronary angiography.

CONCLUSIONS

Comorbid disease is strongly associated with long-term survival in patients with CAD. These data suggest co-existing illnesses should be measured and considered in clinical trials, disease registries, quality comparisons, and counseling of individual patients.