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Biomedical subjects

D B Mark

Publications and source records attributed to D B Mark.

At least 109 records · Page 6Linked to original sources
PubMed1995

Peripheral vascular complications in the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT-I).

OBJECTIVES: In-hospital peripheral vascular complications of balloon angioplasty were compared with those of directional atherectomy in the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT-I) to identify patients at risk and evaluate costs and outcomes. BACKGROUND: The incidence, costs and outcomes of peripheral vascular complications after coronary intervention have not been fully characterized as a function of randomly assigned therapy. METHODS: At 35 sites in the United States and Europe, 1,012 patients were randomized. Peripheral vascular complications were defined as the composite of pulse loss, pseudoaneurysm, hematoma > 4 cm in diameter or groin hemorrhage necessitating blood transfusion. Logistic models were derived to 1) predict these complications from baseline and procedural characteristics, 2) test the relevance of randomization assignment, and 3) assess their impact on hospital costs and long-term outcomes. RESULTS: Sixty-seven patients (6.6%) developed peripheral vascular complications, of whom 15 (22.4%) required a blood transfusion, 14 (20.9%) underwent vascular surgery, and 2 (3.0%) died. Both in-hospital deaths occurred in patients with peripheral vascular complications. There was no difference in composite peripheral vascular complication rates among patients randomized to angioplasty or atherectomy. Greater age, female gender, postprocedural heparin and intraaortic balloon counterpulsation were predictive of increased risk. In a representative 60% subset, mean hospital costs increased from $9,583 in patients without to $18,350 in those with peripheral vascular complications (p = 0.0001). The unadjusted mortality rate at 1 year was 7.5% for patients with peripheral vascular complications compared with 1.1% for all others (p = 0.0001). These complications identified patients at greater risk of death, myocardial infarction or repeat revascularization at 30 days and 1 year. The atherectomy group had a trend toward more frequent deaths and myocardial infarction. CONCLUSIONS: Directional atherectomy and balloon angioplasty had similar in-hospital peripheral vascular complication rates. Female gender, greater age, postprocedural heparin and intraaortic balloon counterpulsation were predictive of higher risk. The twofold increase in cost and sevenfold increase in long-term deaths highlight the need to prevent these periprocedural events and monitor patients closely.

Angioplasty, Balloon, Coronary↗
PubMed1995

Differences in the treatment of myocardial infarction between the United States and Canada. A survey of physicians in the GUSTO trial.

Treatment of acute myocardial infarction differs between the United States and Canada, but the reasons for these practice pattern differences remain elusive. To investigate whether physician beliefs and access to procedures account for these differences in the treatment of acute myocardial infarction, a random sample of physicians involved in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries trial in the United States (n = 332) and Canada (n = 200) was surveyed. We found that American physicians recommend coronary angiography after uncomplicated infarction significantly more (median: 7 versus 3 of 11 possible indications, P = 0.0001). Coronary angiography, angioplasty, and bypass surgery were available in-hospital to more American than Canadian physicians (77% versus 41%), and the reported waiting period for cardiac procedures in a stable patient was longer in Canada (angiography: 28 versus 1.5 days; angioplasty: 30 versus 2 days; bypass surgery: 84 versus 3 days, all P < 0.001). More American than Canadian physicians were cardiologists (88% versus 74%), and more were interventional cardiologists (61% versus 26%). American physicians more highly rated the importance of patient requests, malpractice, and insurance coverage, whereas Canadians more highly rated availability of cardiac procedures as influencing clinical decisions. After statistical adjustment for these factors, however, Americans remained significantly more likely to recommend coronary angiography.

Adult↗
PubMed1994

The relation between the volume of coronary angioplasty procedures at hospitals treating Medicare beneficiaries and short-term mortality.

BACKGROUND: Previous studies have found that hospitals at which more procedures, such as coronary-artery bypass grafting (CABG) and other vascular surgery, are performed have lower rates of mortality related to these procedures than hospitals where fewer such procedures are performed. METHODS: We examined the relation between the number of percutaneous transluminal coronary angioplasty (PTCA) procedures performed at hospitals (volume) and short-term mortality in a population of 217,836 Medicare beneficiaries 65 years of age or older who underwent angioplasty in the United States from 1987 through 1990. RESULTS: The unadjusted in-hospital mortality among patients who underwent PTCA increased from 2.5 percent among the 10 percent of patients treated in hospitals with the highest volume of such procedures to 3.9 percent among the 10 percent of patients treated in hospitals with the lowest volume. The rate of bypass surgery after PTCA also increased, from 2.8 percent among patients in the highest-volume hospitals to 5.3 percent among those in the lowest-volume hospitals. Higher rates of mortality and CABG persisted in all the groups of patients treated in hospitals that performed fewer than 100 angioplasty procedures per year in Medicare beneficiaries; this volume in Medicare beneficiaries can be extrapolated to an overall annual volume of 200 to 400 angioplasty procedures. In a logistic-regression model, the volume of PTCA procedures at a hospital was found to be a highly significant predictor of in-hospital mortality (P < 0.001). These results suggest that if the hospitals with the lowest volume had achieved the experience and technical results of the highest-volume hospitals, 381 fewer patients would have undergone CABG and there would have been 300 fewer in-hospital deaths in the population we studied. CONCLUSIONS: Hospitals that perform more PTCA procedures have lower short-term mortality rates after the procedure. These data provide evidence in support of the regionalization of angioplasty services.

Aged↗
PubMed1994

Changes in mortality after myocardial revascularization in the elderly. The national Medicare experience.

OBJECTIVE: To examine secular changes in the use and outcome of percutaneous transluminal coronary angioplasty and cardiac bypass graft surgery in the elderly. DESIGN: A retrospective cohort study based on a longitudinal database created from the administrative files of Medicare. SETTING: U.S. hospitals that perform myocardial revascularization procedures covered by Medicare. PATIENTS: 225,915 consecutive patients who had angioplasty and 357,885 consecutive patients who had bypass surgery from 1987 to 1990. MEASUREMENTS: The rates of angioplasty and bypass surgery use; unadjusted 30-day and 1-year mortality rates after revascularization; and adjusted odds ratios for mortality by year of procedure for 1987 to 1990. RESULTS: From 1987 to 1990, the rates of angioplasty and bypass surgery done in the elderly increased by 55% and 18%, respectively. During this period, 30-day unadjusted mortality rates after angioplasty and bypass surgery decreased by 25% (95% CI, 22% to 28%) and 12% (CI, 10% to 14%), and 1-year mortality rates decreased by 10% (CI, 8% to 11%) and 8% (CI, 7% to 10%), respectively. After adjustment for changes in patient characteristics, 30-day mortality rates after these procedures decreased by 37% (CI, 32% to 41%) and 18% (CI, 14% to 21%), and 1-year mortality rates decreased by 22% (CI, 18% to 25%) and 19% (CI, 16% to 21%), respectively. CONCLUSIONS: The use of cardiac revascularization procedures in the elderly has steadily increased. Patients who had revascularization are progressively older, have more coded comorbid conditions, and present with more acute diseases. Although elderly patients have apparently higher risk profiles, mortality rates after angioplasty and bypass surgery in the elderly have decreased, suggesting a national improvement in the outcomes of these interventions. Health policy decisions concerning revascularization procedures in the elderly must consider these trends in improved outcome.

Age Factors↗
PubMed1994

Use of medical resources and quality of life after acute myocardial infarction in Canada and the United States.

BACKGROUND: Much attention has been directed to the use of medical resources and to patients' outcomes in Canada as compared with the United States. We compared U.S. and Canadian patients with respect to their use of medical resources and their quality of life during the year after acute myocardial infarction. METHODS: A total of 2600 U.S. and 400 Canadian patients were randomly selected from the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) trial. Base-line data from their initial hospitalizations were analyzed, and the patients were then interviewed by telephone 30 days, 6 months, and 1 year after myocardial infarction to determine their use of medical care and quality of life. RESULTS: The Canadian patients typically stayed in the hospital one day longer (P = 0.009) than the U.S. patients but had a much lower rate of cardiac catheterization (25 percent vs. 72 percent, P < 0.001), coronary angioplasty (11 percent vs. 29 percent, P < 0.001), and coronary bypass surgery (3 percent vs. 14 percent, P < 0.001). At one year 24 percent of the Canadian and 53 percent of the U.S. patients had undergone angioplasty or bypass surgery at least once (P < 0.001). The Canadian had more visits to physicians during the follow-up year (P < 0.001), but fewer visits to specialists (P < 0.001). At 30 days, functional status was equivalent in the patients from the two countries. However, after one year the U.S. patients had substantially more improvement than the Canadian patients (P < 0.001). The prevalence of chest pain and dyspnea at one year was higher among the Canadian patients (34 percent vs. 21 percent and 45 percent vs. 29 percent, respectively; P < 0.001). CONCLUSIONS: The Canadian patients had more cardiac symptoms and worse functional status one year after acute myocardial infarction than the U.S. patients. The Canadian patients also underwent fewer invasive cardiac procedures and had fewer visits to specialist physicians. These results suggest, but do not prove, that the more aggressive pattern of care in the United States may have been responsible for the better quality of life.

Aged↗
PubMed1994

Absence of sex bias in the referral of patients for cardiac catheterization.

BACKGROUND: It has been suggested that women with clinical evidence of coronary artery disease are less often referred for cardiac catheterization than are men. To determine whether there is sex-related bias in referral for cardiac catheterization, we prospectively studied a cohort of 410 symptomatic outpatients (280 men and 130 women) who were being evaluated with exercise testing for possible-coronary artery disease. METHODS: Before the patients underwent exercise testing, 15 cardiologists from an academic medical center were asked to predict the probability that the patients they saw in the cardiology clinic would have angiographic evidence of any obstructive coronary disease (stenosis of 75 percent or more); the probability of severe coronary disease (three-vessel or left main coronary artery disease); the probability of left main coronary artery disease; and the probability of survival one, three, and five years after the evaluation. Similar predictions were generated by previously validated statistical models with use of data collected before exercise testing from the history, physical examination, and 12-lead electrocardiography with the patient at rest. RESULTS: Overall, women were referred for cardiac catheterization significantly less often than men (18 percent vs. 27 percent, P = 0.03). As compared with men, women had a significantly lower pretest probability of coronary disease (as estimated by their physicians) and a lower rate of positive exercise-test results. After accounting for differences in these two factors, sex was not an independent predictor of referral for catheterization. Comparing physicians' estimates of outcome with those generated by the statistical models revealed no evidence that the physicians were underestimating the risk of coronary disease in women. Furthermore, physicians' predictions did not underestimate the probability of any obstructive coronary disease in men and women who subsequently underwent catheterization. CONCLUSIONS: Academic cardiologists made appropriately lower pretest predictions of categories of disease in women with possible coronary artery disease than in men, and these assessments, along with women's lower rate of positive exercise tests, rather than bias based on sex, accounted for the lower rate of catheterization among women.

Aged↗
PubMed1994

An overview of risk assessment in coronary artery disease.

Risk assessment is a central activity in virtually all aspects of the examination and treatment of patients. Methods to standardize this process and improve its accuracy can only improve the quality of medical care. Since health care is undergoing reform in this country, it seems likely that physicians will increasingly need objective justification for their decision making. Risk assessment models offer a potentially useful tool. The Duke Treadmill Score is well-validated and clinically useful for risk assessment in patients with either established or suspected coronary artery disease for whom the desirability of additional invasive testing must be determined. One of the major goals of risk assessment is to identify the low-risk patients for whom no additional testing is required. Whereas multiple valid strategies for accomplishing this exist, there is no consensus on the optimal approach. Cost-containment pressures may indicate the use of exercise testing as the preferred initial strategy in patients who are able to exercise and have an interpretable electrocardiogram. Exercise nuclear testing could thus be reserved for patients in the intermediate-risk group for whom the additional accuracy of these latter tests would provide a more precise risk-stratification estimate. For patients unable to exercise, a pharmacologic stress test (such as echocardiography with dobutamine or an adenosine isonitrile study) would be an acceptable alternative.

Coronary Disease↗
PubMed1994

Intracranial hemorrhage risk and new thrombolytic therapies in acute myocardial infarction.

Thrombolytic therapy for acute myocardial infarction (AMI) has reduced mortality at the expense of additional intracranial hemorrhages. To determine whether this trade-off has been optimized, a decision analysis was performed using pooled data to determine the further reductions in mortality required to justify increased intracranial hemorrhage rates from more potent thrombolytic and adjunctive antithrombotic regimens that intravenous streptokinase. Pooled data from large clinical trials suggest that streptokinase has a 0.07% nonfatal intracranial hemorrhage rate. Approximately 54% of these result in major/moderate disability and 46% in recovery or minor residual. The early mortality rate in all AMI patients treated with thrombolytic therapy is 9.8%; it is 6.8% in patients with inferior wall AMI and 17.9% in elderly patients. If a new thrombolytic regimen provides a 1% absolute reduction in early mortality compared with streptokinase therapy, approximately a > or = 3.2% nonfatal intracranial hemorrhage rate is justified to obtain this survival benefit. For a 10% relative reduction in mortality risk, the maximal acceptable nonfatal intracranial hemorrhage rates are 2.2% for inferior wall AMI, 3.2% for all patients and 5.9% for elderly patients. Whereas intracranial hemorrhage is a catastrophic complication of thrombolytic therapy in the treatment of patients with AMI, thrombolytic regimens that result in significantly higher rates of intracranial hemorrhage than those observed with streptokinase may be preferable at surprisingly smaller additional reductions in mortality. In addition to evaluating new thrombolytic and antithrombotic regimens, this analysis, in conjunction with models that predict patient-specific intracranial hemorrhage risks and mortality benefits from thrombolytic therapy, can provide a framework for matching AMI patients with optimal thrombolytic regimens.

Aged↗
PubMed1994

Effects of coronary angioplasty, coronary bypass surgery, and medical therapy on employment in patients with coronary artery disease. A prospective comparison study.

OBJECTIVE: To compare return-to-work rates after coronary angioplasty, coronary bypass surgery, and medical therapy in patients with coronary disease. DESIGN: Prospective cohort study. SETTING: Tertiary care referral center. PATIENTS: Between March 1986 and June 1990, we enrolled 1252 patients who were younger than 65 years, who had not had previous coronary revascularization, and who were employed. All patients were followed for 1 year. MAIN OUTCOME MEASURE: One-year employment status. RESULTS: After 1 year, 84% of patients who had coronary angioplasty were still working compared with 79% of patients who had bypass surgery and with 76% of patients who received medicine. After adjusting for the more favorable baseline characteristics of patients who had angioplasty (less severe coronary artery disease, better left ventricular function, and less functional impairment), however, no significant differences were noted in 1-year employment rates among the three groups. These adjusted 1-year return-to-work rates were 84% for angioplasty, 80% for surgery, and 79% for medicine (P > 0.05). In a random subset of 72 patients, 23 patients who had angioplasty returned to work after a median of 18 days (mean, 27 days) compared with 54 days (mean, 67 days) for 24 patients having bypass surgery and with 14 days (mean, 45 days) for 25 patients receiving medicine (P = 0.002). CONCLUSIONS: Patients who had coronary angioplasty were able to return to work earlier than those who had bypass surgery, but by 1 year no significant difference was noted in employment rates. Neither revascularization strategy improved employment rates when compared with initial treatment using medical therapy.

Angioplasty, Balloon, Coronary↗
PubMed1994

Continuing evolution of therapy for coronary artery disease. Initial results from the era of coronary angioplasty.

BACKGROUND: Survival after coronary artery bypass graft surgery (CABG) and medical therapy in patients with coronary artery disease (CAD) has been studied in both randomized trials and observational treatment comparisons. Over the past decade, the use of coronary angioplasty (PTCA) has increased dramatically, without guidance from either randomized trials or prospective observational comparisons. The purpose of this study was to describe the survival experience of a large prospective cohort of CAD patients treated with medicine, PTCA, or CABG. METHODS AND RESULTS: The study was designed as a prospective nonrandomized treatment comparison in the setting of an academic medical center (tertiary care). Subjects were 9263 patients with symptomatic CAD referred for cardiac catheterization (1984 through 1990). Patients with prior PTCA or CABG, valvular or congenital disease, nonischemic cardiomyopathy, or significant (> or = 75%) left main disease were excluded. Baseline clinical, laboratory, and catheterization data were collected prospectively in the Duke Cardiovascular Disease Databank. All patients were contacted at 6 months, 1 year, and annually thereafter (follow-up 97% complete). Cardiovascular death was the primary end point. Of this cohort, 2788 patients were treated with PTCA (2626 within 60 days) and 3422 with CABG (3080 within 60 days). Repeat or crossover revascularization procedures were counted as part of the initial treatment strategy. Kaplan-Meier survival curves (both unadjusted and adjusted for all known imbalances in baseline prognostic factors) were used to examine absolute survival differences, and treatment pair hazard ratios from the Cox model were used to summarize average relative survival benefits. For the latter, a 13-level CAD prognostic index was used to examine the relation between survival and revascularization as a function of CAD severity. The effects of revascularization on survival depended on the extent of CAD. For the least severe forms of CAD (ie, one-vessel disease), there were no survival advantages out to 5 years for revascularization over medical therapy. For intermediate levels of CAD (ie, two-vessel disease), revascularization was associated with higher survival rates than medical therapy. For less severe forms of two-vessel disease, PTCA had a small advantage over CABG, whereas for the most severe form of two-vessel disease (with a critical lesion of the proximal left anterior descending artery), CABG was superior. For the most severe forms of CAD (ie, three-vessel disease), CABG provided a consistent survival advantage over medicine. PTCA appeared prognostically equivalent to medicine in these patients, but the number of PTCA patients in this subgroup was low. CONCLUSIONS: In this first large-scale, prospective observational treatment comparison of PTCA, CABG, and medicine, we confirmed the previously reported survival advantages for CABG over medical therapy for three-vessel disease and severe two-vessel disease. For less severe CAD, the primary treatment choices are between medicine and PTCA. In these patients, there is a trend for a relative survival advantage with PTCA, although absolute survival differences were modest. In this setting, treatment decisions should be based not only on survival differences but also on symptom relief, quality of life outcomes, and patient preferences.

Angioplasty, Balloon, Coronary↗
PubMed1994

Diagnosing and managing unstable angina. Agency for Health Care Policy and Research.

This Quick Reference Guide for Clinicians contains recommendations on the care of patients with unstable angina based on a combination of evidence obtained through extensive literature reviews and consensus among members of an expert panel. Principal conclusions include the following. (1) Many patients suspected of having unstable angina can be discharged home after adequate initial evaluation. (2) Further outpatient evaluation may be scheduled for up to 72 hours after initial presentation for patients with clinical symptoms of unstable angina judged at initial evaluation to be at low risk for complications. (3) Patients with acute ischemic heart disease judged to be at intermediate or high risk of complications should be hospitalized for careful monitoring of their clinical course. (4) Intravenous thrombolytic therapy should not be administered to patients without evidence of ST segment elevation and acute myocardial infarction. (5) Assessment of prognosis by noninvasive testing often aids selection of appropriate therapy. (6) Coronary angiography is appropriate for patients judged to be at high risk for cardiac complications or death based on their clinical course or results of noninvasive testing. (7) Coronary artery bypass surgery should be recommended for almost all patients with left main disease and many patients with three-vessel disease, especially those with left ventricular dysfunction. (8) The discharge care plan should include continued monitoring of symptoms; appropriate drug therapy, including aspirin; risk-factor modification; and counseling.

Ambulatory Care↗
PubMed1994

Percutaneous intervention, surgery, and medical therapy: a perspective from the Duke Databank for Cardiovascular Diseases.

Myocardial revascularization improves survival rates and quality of life for patients with symptomatic ischemic heart disease. The less severe the anatomic disease, the smaller the benefit, particularly for survival. Patients with more severe anatomic disease benefit from surgical therapy, in terms of both survival and quality of life. Continuing advances in pharmacological secondary prevention, percutaneous intervention, and surgical treatment mandate continued analysis of contemporary outcomes to provide the best information for rational decision-making.

Angioplasty, Balloon, Coronary↗
PubMed1994

Risk stratification in patients with chest pain.

The evaluation of patients with chest pain and suspected coronary disease remains a challenge for primary care physicians. In this article, three major points are emphasized. First, making full use of the data collected during the initial encounter prior to performance of an exercise test is helpful in formulating assessments of both the likelihood of significant coronary disease and of the short-term risk of a major cardiac event. Second, exercise testing is helpful for intermediate-likelihood patients because positive tests in low-likelihood patients cannot "rule in" disease, and negative tests in high-likelihood patients cannot "rule out" disease. Finally, exercise testing in risk stratification of the patient with suspected coronary artery disease is valuable in identifying low-risk patients in whom further testing, including catheterization, may be safely deferred.

Chest Pain↗
PubMed1993

Discordance of databases designed for claims payment versus clinical information systems. Implications for outcomes research.

OBJECTIVE: To determine the suitability of insurance claims information for use in clinical outcomes research in ischemic heart disease. DESIGN: Concordance study of two databases. SETTING: Tertiary care referral center. PATIENTS: A total of 12,937 consecutive patients hospitalized for cardiac catheterization for suspected ischemic heart disease between July 1985 and May 1990. INTERVENTIONS: Two-by-two tables were used to compute overall and kappa measures of agreement comparing clinical versus claims data for 12 important predictors of prognosis in patients with ischemic heart disease. MEASUREMENTS: Kappa statistics (agreement adjusted for chance agreement) were used to quantify agreement rates. RESULTS: Agreement rates between the clinical and claims databases ranged from 0.83 for the diagnosis of diabetes to 0.09 for the diagnosis of unstable angina (kappa values). Claims data failed to identify more than one half of the patients with prognostically important conditions, including mitral insufficiency, congestive heart failure, peripheral vascular disease, old myocardial infarction, hyperlipidemia, cerebrovascular disease, tobacco use, angina, and unstable angina, when compared with the clinical information system. CONCLUSIONS: Our results suggest that insurance claims data lack important diagnostic and prognostic information when compared with concurrently collected clinical data in the study of ischemic heart disease. Thus, insurance claims data are not as useful as clinical data for identifying clinically relevant patient groups and for adjusting for risk in outcome studies, such as analyses of hospital mortality.

Cardiac Catheterization↗
PubMed1993

Value of the history and physical in identifying patients at increased risk for coronary artery disease.

OBJECTIVE: To determine whether information from the physician's initial evaluation of patients with suspected coronary artery disease predicts coronary anatomy at catheterization and 3-year survival. DESIGN: Prospective validation of regression model estimates in an outpatient cohort. SETTING: University medical center. PATIENTS: A total of 1030 consecutive outpatients referred for noninvasive testing for suspected coronary artery disease; 168 of these patients subsequently underwent catheterization within 90 days. MEASUREMENTS: Information from the initial history, physical examination, electrocardiogram, and chest radiograph was used to predict coronary anatomy (the likelihood of any significant coronary disease, severe disease [left main or three-vessel], and significant left main disease) among 168 catheterized patients and to estimate 3-year survival among all patients. These estimates were compared with those based on treadmill testing. Cardiovascular testing charges were calculated for all patients. RESULTS: Predicted coronary anatomy and survival closely corresponded to actual findings. Compared with the treadmill exercise test, initial evaluation was slightly better able to distinguish patients with or without any coronary disease and was similar in the ability to identify patients at increased risk for dying or with anatomically severe disease. Based on arbitrary definitions, 37% to 66% of patients were at low risk and responsible for 31% to 56% of the charges for cardiovascular testing. CONCLUSIONS: The physician's initial evaluation, despite the subjective nature of much of the information gathered, can be used to identify patients likely to benefit from further testing. The development of strategies for cost-conscious quality care must begin with the history, physical examination, and simple laboratory testing.

Aged↗
PubMed1993

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.

Aged↗
PubMed1992

Referral patterns for coronary artery disease treatment: gender bias or good clinical judgment?

OBJECTIVE: To determine whether a gender bias exists in referral for coronary bypass graft surgery among patients with catheterization-documented coronary artery disease. DESIGN: Historical cohort study (1969 to 1984). SETTING: A referral medical center. PATIENTS: A total of 5795 patients with catheterization-documented coronary artery disease. MEASUREMENTS: Surgical referral patterns of men and women grouped by risk for cardiac death and by treatment effectiveness. Time trends were evaluated for three periods: 1969 to 1974, 1975 to 1979, and 1980 to 1984. RESULTS: Overall, when no adjustment was made for baseline risk for cardiac death, no statistical difference was found between men and women regarding referral for surgery (46% compared with 44%, respectively). When an adjustment was made for such risk, the male-to-female odds ratio for surgical referral was 1.28 (95% Cl, 1.05 to 1.58) among patients with a low risk for cardiac death. This effect was most evident in the 1980 to 1984 period (odds ratio, 1.73; Cl, 1.29 to 2.31). In the high-risk group, the odds ratio was 0.84 (Cl, 0.68 to 1.04), with little change occurring during the study. Men were more likely to be referred for surgery when surgery offered the least survival benefit relative to medical therapy (odds ratio, 1.29; Cl, 1.08 to 1.54). This effect was most pronounced in the 1980 to 1984 period (odds ratio, 1.63; Cl, 1.27 to 2.10). CONCLUSIONS: Women are less likely than men to be referred for coronary bypass graft surgery among patients with a low risk for cardiac death, in whom surgery offers little or no survival benefit over medical treatment. Women are at least as likely as men to be referred for bypass surgery among more symptomatic and more severely diseased patients, in whom surgery offers the greatest survival benefits. These trends were most prominent in the recent years of the study. Based on surgical survival benefits, these referral patterns may represent more appropriate treatment referral for women than men.

Coronary Artery Bypass↗