Use of Medical Resources and Quality of Life after Acute Myocardial Infarction in Canada and the United States
Daniel B. Mark, C. David Naylor, Mark A. Hlatky, Robert M. Califf, Eric J. Topol, Christopher B. Granger, J. David Knight, Charlotte L. Nelson, Kerry L. Lee, Nancy E. Clapp-Channing, Wanda Sutherland, Louise Pilote, and Paul W. Armstrong
Background Much attention has been directed to the use of medicalresources and to patients' outcomes in Canada as compared withthe United States. We compared U.S. and Canadian patients withrespect to their use of medical resources and their qualityof life during the year after acute myocardial infarction.
Methods A total of 2600 U.S. and 400 Canadian patients wererandomly selected from the Global Utilization of Streptokinaseand t-PA for Occluded Coronary Arteries (GUSTO) trial. Base-linedata from their initial hospitalizations were analyzed, andthe patients were then interviewed by telephone 30 days, 6 months,and 1 year after myocardial infarction to determine their useof medical care and quality of life.
Results The Canadian patients typically stayed in the hospitalone day longer (P = 0.009) than the U.S. patients but had amuch lower rate of cardiac catheterization (25 percent vs. 72percent, P<0.001), coronary angioplasty (11 percent vs. 29percent, P<0.001), and coronary bypass surgery (3 percentvs. 14 percent, P<0.001). At one year 24 percent of the Canadianand 53 percent of the U.S. patients had undergone angioplastyor bypass surgery at least once (P<0.001). The Canadianshad more visits to physicians during the follow-up year (P<0.001),but fewer visits to specialists (P<0.001). At 30 days, functionalstatus was equivalent in the patients from the two countries.However, after one year the U.S. patients had substantiallymore improvement than the Canadian patients (P<0.001). Theprevalence of chest pain and dyspnea at one year was higheramong the Canadian patients (34 percent vs. 21 percent and 45percent vs. 29 percent, respectively; P<0.001).
Conclusions The Canadian patients had more cardiac symptomsand worse functional status one year after acute myocardialinfarction than the U.S. patients. The Canadian patients alsounderwent fewer invasive cardiac procedures and had fewer visitsto specialist physicians. These results suggest, but do notprove, that the more aggressive pattern of care in the UnitedStates may have been responsible for the better quality of life.
Many studies have compared the structure and process of healthcare in the United States with those in Canada, but few haveexamined medical outcomes and almost none have compared qualityof life1. Recently, Rouleau and colleagues compared U.S. andCanadian patients after acute myocardial infarction2. They foundsignificantly more use of coronary angiography and coronary-revascularizationprocedures in the United States but equivalent mortality andrates of reinfarction. Although quality of life was not assessed,these investigators did find a significantly higher incidenceof activity-limiting angina at one year in Canada.
From 1990 to 1993, the Global Utilization of Streptokinase andt-PA for Occluded Coronary Arteries (GUSTO) trial enrolled 41,021patients with acute myocardial infarction in 15 countries ina randomized comparison of four strategies of thrombolytic treatment3.In the present study, a substudy of GUSTO, we examined patternsof medical practice and quality-of-life outcomes in a randomlyselected subgroup of patients from Canada and the United Statesduring the year after myocardial infarction.
Methods
Patients
The eligibility criteria for the GUSTO trial have been describedpreviously3. Briefly, patients presenting to a participatinghospital within six hours of the onset of symptoms consistentwith a diagnosis of acute myocardial infarction and with electrocardiographicST-segment elevation were eligible for enrollment unless theyhad had a previous stroke, were actively bleeding, or met otherstandard exclusion criteria for thrombolysis.
Overview of the Substudy
Patients from North America who were enrolled in the trial wererandomly selected for additional participation in a substudyon economics and quality of life in GUSTO. The sampling fractionwas approximately 1 in 8, yielding an enrollment in the substudyof 2600 U.S. patients (out of 23,105) and 400 Canadian patients(out of 2898). The substudy patients were contacted by telephone30 days, 6 months, and 1 year after myocardial infarction. At30 days and 1 year, they were asked to participate in a detailed20- to 30-minute structured interview covering their medicalcare during the interval and their current health-related qualityof life. At six months, they had a 10-minute structured interviewcovering medical care during the interval and selected quality-of-lifemeasures. In the case of patients who died or were unable tobe interviewed, a proxy interview concentrating on medical careduring the interval was conducted with a member of the householdor the nearest relative. No subjective assessments of qualityof life were made on the basis of the proxy interviews. Interviewsin the United States were conducted by the computer-assistedtelephone interview unit of the Research Triangle Institute,whereas those in Canada were carried out by members of the DukeCoordinating Center staff and by a nurse in Quebec in the caseof French-speaking participants. All the interviewers were trainedat the beginning of the study by the senior coordinator of thesubstudy.
Data on Consumption of Medical Resources
Data on the consumption of medical resources from the time ofthe base-line hospitalization were collected on the case-reportform3. In each follow-up interview, patients were asked aboutmedical care during the interval, including rehospitalization,cardiac catheterization, coronary angioplasty, coronary bypasssurgery, myocardial infarction, nursing home placement, andoutpatient visits to 11 different types of practitioners orcare facilities. All cardiac procedures reported by the patientswere documented from the source by checking both the occurrenceand the date or dates of the procedure with the relevant facilityproviding medical care.
Quality-of-Life Assessment
We measured quality of life in five major domains with a batteryof instruments4. Functional status was assessed with the DukeActivity Status Index,5 the Katz Activities of Daily LivingScale6 (at one year only), a single four-level question aboutthe effects of the patient's health on overall functioning,and questions about bed days and reduced-activity days takenfrom the National Health Interview Survey7. Angina and dyspneawere assessed with the Rose questionnaires8. Perceptions ofgeneral health were assessed on a scale ranging from excellentto poor that was taken from the National Health Interview Survey7.Employment status was evaluated with a detailed set of questionsadapted from the Bypass Angioplasty Revascularization Investigation9.General psychological well-being was evaluated with a 10-itemscale created for this study from published instruments (availableon request from Dr. Mark). In addition, the brief Carroll DepressionScale was used to assess depression10. In conjunction with thesehealth-related quality-of-life assessments, we measured patients'preferences for their own states of health relative to excellenthealth at 30 days and 1 year11,12. At the one-year follow-uppoint, patients were also asked to rate their overall healthon a scale ranging from 0 to 100, on which 100 represented excellenthealth.
Statistical Analysis
For the present study, all four thrombolytic treatment groupswere combined and the U.S. and Canadian patients were compared.The descriptive statistics for this study are presented as mediansand interquartile ranges (25th and 75th percentiles) in thecase of continuous variables and as percentages in the caseof discrete variables. Univariate testing was performed withstandard contingency-table chi-square tests or Fisher's exacttest for categorical variables and the Wilcoxon rank-sum testfor continuous variables. Kaplan-Meier survival estimates (unadjusted)and the Cox proportional-hazards regression model (adjusted)were used to compare the complete U.S. and Canadian GUSTO cohortswith respect to survival to one year13,14. One-year mortalitydata for the entire North American cohort are 99 percent complete.For this substudy, interviews with patients (including proxies)were conducted with 96 percent of the scheduled follow-up contactsin both countries (there was a 1.6 percent refusal rate anda 2.1 percent loss to follow-up at one year). Multivariablelinear-regression analysis was used to examine the relationof different degrees of revascularization during the first 30days of the study to subsequent changes in functional status,as reflected in the Duke Activity Status Index. All reportedP values are two-tailed.
Results
Base-Line Characteristics and Medical Treatment
The clinical characteristics of the patients with acute myocardialinfarction in Canada and the United States were generally similarat entry (Table 1). More Canadians had a history of angina (P= 0.02), whereas more U.S. patients had a previous coronaryangioplasty (P<0.001). Fewer Canadians had a history of hypertension,but the distribution of blood pressures at admission was significantlyhigher in Canada than in the United States. In-hospital useof intravenous nitroglycerin, intravenous beta-blockers, andlidocaine was more common in the United States (all P<0.001).At discharge, however, significantly more Canadian patientswere sent home taking beta-blockers (P = 0.001) and angiotensin-converting-enzymeinhibitors (P = 0.02), whereas significantly more U.S. patientswent home taking nitrates (P = 0.001), calcium blockers (P<0.001),or digitalis (P<0.001).
Table 1. Characteristics of the Study Patients at Presentation.
Consumption of Medical Resources
Base-Line Hospitalization
The initial hospitalization lasted one day longer in Canadathan in the United States (P = 0.009), whereas the length ofstay in the intensive care unit was identical in the two countries(P = 0.81). More U.S. patients were hospitalized initially ata facility with the capability of performing cardiac catheterization(80 percent vs. 38 percent, P<0.001), angioplasty (56 percentvs. 34 percent, P<0.001), and bypass surgery (55 percentvs. 30 percent, P<0.001). Cardiac procedures were performedduring the hospitalization for acute myocardial infarction significantlymore often in U.S. patients: angiography in 72 percent, as comparedwith 25 percent of the Canadian patients (P<0.001); coronaryangioplasty in 29 percent, as compared with 11 percent (P<0.001);and coronary bypass surgery in 14 percent, as compared with3 percent (P<0.001). Similar trends were seen in the useof invasive procedures in the intensive care unit: among patientswho did not undergo bypass surgery, U.S. patients received morepulmonary-artery catheters (11 percent vs. 3 percent, P<0.001),temporary transvenous pacemakers (7 percent vs. 4 percent, P= 0.03), intraaortic balloon pumps (4 percent vs. <1 percent,P<0.001), and mechanical ventilators (6 percent vs. 3 percent,P = 0.008).
Follow-up
The higher use of cardiac catheterization and revascularizationin the United States persisted throughout the one-year follow-up.By the end of one year, 24 percent of the Canadian patientsand 53 percent of the U.S. patients had undergone coronary angioplastyor bypass surgery at least once (P<0.001). Cardiac procedureswere also performed sooner after infarction in the United States:for angiography, a median of 4 vs. 11 days (P<0.001), andfor revascularization, 5 vs. 16 days (P<0.001).
Canadian patients were significantly more likely to visit aphysician during the year after their myocardial infarctionbut were significantly less likely to visit a specialist (Figure 1).Participation in cardiac-rehabilitation programs was significantlymore common in the United States (38 percent, vs. 32 percentin Canada; P = 0.02).
Figure 1. Outpatient Visits to Physicians during the Postinfarction Year, According to Country, along with Visits to Cardiologists, Internists, and Family or General Practitioners.
The Canadian patients had significantly more visits to physicians, as well as more visits to family or general practitioners, whereas U.S. patients had significantly more visits to cardiologists and internists.
Medical and Quality-of-Life Outcomes
Survival, Reinfarction, and Stroke
The unadjusted survival rates for the entire U.S. cohort of23,105 patients at 24 hours, 30 days, and 1 year were 97.3,93.2, and 90.7 percent, respectively. The corresponding figuresfor the entire Canadian cohort of 2898 patients were 96.8, 92.4,and 90.3 percent, respectively (P = 0.33 for unadjusted comparisons).After adjustment for all available base-line prognostic factorswith the Cox regression model, the U.S. cohort had a significantlyhigher survival than the Canadian cohort (P = 0.02). In-hospitalreinfarction occurred in 3.7 percent of the U.S. and 4.5 percentof the Canadian patients in GUSTO (P = 0.06), whereas recurrentmyocardial ischemia occurred in the hospital in 22 percent and24 percent, respectively (P = 0.30). Rates of reinfarction afterdischarge were not assessed in this study. In-hospital strokeoccurred in 1.6 percent of the U.S. and 1.5 percent of the Canadianpatients (P = 0.69).
Quality of Life
One month after myocardial infarction, the Canadian and theU.S. participants reported generally comparable functional statusas assessed by the Duke Activity Status Index, but by the endof one year of follow-up, the Canadian participants reportedgenerally lower physical and emotional status (Table 2). Thechange in scores for individual patients from 30 days to 1 year,as well as the patients' own assessments of changes at 1 yearrelative to their status before myocardial infarction (Table 3)confirmed that significantly more Canadian than U.S. patientsregarded their status as having worsened at 1 year. These resultsparalleled the findings with respect to symptoms, in which significantlymore Canadians reported chest pain (34 percent vs. 21 percent)and dyspnea (45 percent vs. 29 percent) at one year (Figure 2).
Symptoms were assessed with the Rose angina and dyspnea questionnaires8. The Canadian patients reported significantly more chest pain, angina, and dyspnea than the U.S. patients when symptoms with all degrees of severity were considered.
General perceptions of health (rated from excellent to poor)were equivalent at both 30 days and 1 year, but general healthat 1 year, rated on a scale from 0 to 100, was better in theU.S. cohort (Table 2). Employment status and number of hoursworked per week were equivalent before myocardial infarctionand at 1 year in the two groups (Table 2), but the time beforea return to work after myocardial infarction was shorter inthe United States: median, 58 days (25th to 75th percentile,30 to 100 days), as compared with 81 days in Canada (25th to75th percentile, 45 to 162 days; P<0.001). Among patientswho were working at one year (either for pay or in the home),the amount and quality of work as compared with those beforethe myocardial infarction were considered the same in the twocohorts, but Canadians adjusted their work activities more oftenbecause of their health (Table 3).
Coronary Revascularization and Quality-of-Life Outcomes at One Year
For patients who did not have coronary angioplasty or bypasssurgery within the first 30 days after enroll ment, the distributionof Duke Activity Status Index scores at 30 days was very similarin the two countries (Figure 3). By one year, however, althoughboth cohorts improved significantly, the scores for the U.S.cohort had shifted up in relation to those of the Canadian cohort(P<0.001). Patients from the two countries who underwentrevascularization in the first 30 days had equivalent Duke ActivityStatus Index scores at 30 days (P = 0.47) and higher scoresin the United States at 1 year (P = 0.03).
Figure 3. Comparison of 30-Day and 1-Year Values on the Duke Activity Status Index, According to Revascularization Status at 30 Days.
Both revascularization subgroups had similar values at 30 days. At one year, both subgroups had improved significantly, but the U.S. patients improved more than the Canadians. Also, the median and mean values on the Duke Activity Status Index for patients who underwent revascularization were higher at one year in both countries than the values for patients who did not undergo revascularization. Only patients for whom data from the Duke Activity Status Index were complete at both 30 days and 1 year are included.
In a multiple linear-regression model with the change in DukeActivity Status Index between 30 days and 1 year used as thedependent variable and with adjustment for the 30-day scoreand other predictors of change in this measure (including sex,education, prior myocardial infarction, and prior angina), undergoingrevascularization in the first 30 days predicted a 2.3-pointincrease in the Duke Activity Status Index (P<0.001), whereasbeing a U.S. rather than a Canadian patient independently predicteda 3.6-point increment at 1 year (P<0.001).
Discussion
In this prospective comparison of 2600 U.S. and 400 Canadianpatients, the U.S. participants had a substantially better qualityof life one year after acute myocardial infarction. Previousstudies have reported more activity-limiting angina2 and lowerscores on the Duke Activity Status Index15 after myocardialinfarction in Canadian than in U.S. patients. The present studyextends these observations with a broader quality-of-life assessment.Our results challenge the contention that the greater use ofcardiac procedures in the United States as compared with Canada2,15,16has no effect on health outcomes.
One possible explanation for our findings is that the U.S. andCanadian subjects had important sociocultural differences intheir perceptions of quality of life. Another is that the interviewswere conducted differently. The similarity in the responsesof the U.S. and Canadian patients at 30 days with regard togeneral health, functional status, and psychological status,with the subsequent emergence of increasing differences overthe ensuing 11 months, argues against such explanations.
Another possible explanation for our findings is that the Canadianswere more impaired than their U.S. counterparts at the timeof enrollment in the study or had more severe myocardial infarctions.The absolute difference in rates of angina at entry (6 percent)seems unlikely to explain the observed differences in functionalstatus at one year. Adjustment for levels of education and income,both of which were lower among the Canadian patients, did notaffect the differences in one-year functional status. Furthermore,the severity of myocardial infarction was not greater in Canada,as evidenced by an equivalent prevalence of previous myocardialinfarction and similar distributions of Killip class, infarctlocation, and initial heart rate.
The third possible explanation for our findings is that thedifferences in quality of life observed at follow-up were dueto the different patterns of medical care in Canada and theUnited States. However, establishing a direct causal link betweenthe different levels of use of invasive cardiac procedures orother aspects of care and subsequent quality-of-life outcomesis quite difficult. Revascularization procedures do affect healthdirectly, but this effect is complex and is determined to animportant degree by the level of impairment present before treatment.For example, if revascularization was applied in Canada primarilyto patients with severe coronary disease who were too sick torecover completely, whereas in the United States a more aggressiveapproach was taken, with most of the moderately and severelyimpaired patients undergoing revascularization, such differencesin the pattern of care could affect both the average differencebetween countries in one-year functional status and the functionalstatus of subgroups defined by the presence or absence of arevascularization procedure during the preceding year. The difficultyof assigning a causal relation to these observations stems inpart from our inability to obtain a true base-line assessmentof quality of life. Such assessments were not feasible in thepresent study.
It is likely that other aspects of care besides revascularizationaccount for some of the differences we observed in quality oflife. A comparison of medication use shows a higher rate ofearly use of intravenous beta-blockers and nitrates in the UnitedStates. However, the in-hospital use of prophylactic lidocaineand calcium blockers (lower in Canada for both) and the useof beta-blockers and angiotensin-converting-enzyme inhibitorsafter discharge (both higher in Canada) conformed to a patternof care in Canada more consistent with the results of recentrandomized trials and meta-analyses. The greater use of specialtycare in the United States during follow-up, including both morevisits to specialist physicians and more use of cardiac-rehabilitationservices, is another potential explanation for the observeddifferences. Furthermore, our regression analysis of changesin functional-status scores indicates a significant residualcountry-related effect that may well represent unmeasured differencesin the process of care or in sociocultural factors.
There are several important limitations to our study. First,the participants at both the provider and the patient levelwere volunteers. The rates of invasive cardiac procedures forCanada in this study were substantially higher than is typicalof the country overall. Physicians participating in the trialin these countries were probably more aggressive and perhapsmore technologically oriented than the overall population ofphysicians caring for patients with acute myocardial infarction.On balance, it seems likely that the use of volunteer sitesand patients would act to reduce variation and increase similaritybetween countries.
Second, since quality of life is a subjective phenomenon, proofthat the assessment instruments used in a particular study measuredwhat they were intended to measure (and nothing else) is alwaysindirect and incomplete4. To minimize this problem, we useda battery of standard instruments instead of relying on a singleinstrument; the consistency of our results with multiple typesof measures argues against problems of validity involving anyparticular scale.
Although most measures of quality of life in this study showedconsistently more favorable outcomes for U.S. patients, twoimportant measures did not. The patients' perceptions of generalhealth, rated from excellent to poor on an ordinal scale, weresimilar at both 30 days and 1 year. In contrast were the patients'ratings of their current health (at one year) on a scale from0 to 100 and their own comparisons with their status beforemyocardial infarction, both of which indicated more favorableoutcomes in the U.S. patients. Employment rates were also similarin the two cohorts, both before myocardial infarction and atone year.
In conclusion, our results suggest that U.S. patients with acutemyocardial infarction are likely to have better functional statusand fewer cardiac symptoms during the first year after myocardialinfarction than Canadian patients. The evidence from this studysupports, but cannot definitively prove, the hypothesis thatthese superior outcomes are due to differences in the processof care -- specifically, the greater use of revascularizationprocedures and specialist services in the United States. Althoughthese findings cannot be generalized to support arguments aboutthe overall performance of one system as compared with the other,they should stimulate more careful and detailed assessment ofthe relation between structural aspects of different healthcare systems and associated health outcomes.
Supported in part by research grants (HS-05635 and HS-06503)from the Agency for Health Care Policy and Research; by a grantfrom Genentech, South San Francisco, Calif.; by research grants(HL-36587 and HL-17670) from the National Heart, Lung, and BloodInstitute; and by a grant from the Robert Wood Johnson Foundation.
We are indebted to the North American GUSTO clinicians and studycoordinators for their contributions to this project; to theGUSTO Steering Committee for reviewing the manuscript and substantiallyimproving it with their suggestions; to Celia Hybels, M.S.P.H.,Julia Burchett, M.A., and Marie-Claude Caron, R.N., for theirextensive data-collection activities; and to Lori Baysden, SerenaSmith, and Maria Lee for their assistance in the preparationof the manuscript.
Source Information
From the Economic and Quality of Life Research Group (D.B.M., J.D.K., C.L.N., N.E.C.-C.) and the Clinical Trials Coordinating Center (R.M.C., C.B.G., K.L.L.), the Division of Cardiology (D.B.M., R.M.C., C.B.G.), the Department of Medicine and the Division of Biometry, Department of Community and Family Medicine (K.L.L.), Duke University Medical Center, Durham, N.C.; the Department of Medicine, University of Toronto (C.D.N., W.S.), and the Institute for Clinical Evaluative Sciences (C.D.N.), Toronto; the Department of Medicine, University of Alberta, Edmonton (P.W.A.); the Division of Health Services Research, Department of Health Research and Policy, Stanford University Medical Center, Stanford, Calif. (M.A.H.); and the Department of Cardiology, Cleveland Clinic, Cleveland (E.J.T., L.P.).
Address reprint requests to Dr. Mark at P.O. Box 3485, Duke University Medical Center, Durham, NC 27708-3485.
References
Roos LL, Fisher ES, Sharp SM, Newhouse JP, Anderson G, Bubolz TA. Postsurgical mortality in Manitoba and New England. JAMA 1990;263:2453-2458. [Free Full Text]
Rouleau JL, Moye LA, Pfeffer MA, et al. A comparison of management patterns after acute myocardial infarction in Canada and the United States. N Engl J Med 1993;328:779-784. [Free Full Text]
The GUSTO Investigators. An international randomized trial comparing four thrombolytic strategies for acute myocardial infarction. N Engl J Med 1993;329:673-682. [Free Full Text]
Mark DB. Quality of life assessment. In: Califf RM, Mark DB, Wagner GS, eds. Acute coronary care in the thrombolytic era. 2nd ed. Chicago: Year Book Medical (in press).
Hlatky MA, Boineau RE, Higginbotham MB, et al. A brief self-administered questionnaire to determine functional capacity (the Duke Activity Status Index). Am J Cardiol 1989;64:651-654. [CrossRef][Medline]
Katz S, Downs TD, Cash HR, Grotz RC. Progress in development of the index of ADL. Gerontologist 1970;10:20-30. [Medline]
National Center for Health Statistics. Health, United States, 1991. Hyattsville, Md.: Public Health Service, 1992. (DHHS publication no. (PHS) 92-1232.)
Rose GA. Cardiovascular survey methods. 2nd ed. World Health Organization monograph series no. 56. Geneva: World Health Organization, 1982.
The BARI Investigators. Protocol for the Bypass Angioplasty Revascularization Investigation. Circulation 1991;84:Suppl V:V-1.
Koenig HG, Cohen HJ, Blazer DG, Meador KG, Westlund R. A brief depression scale for use in the medically ill. Int J Psychiatry Med 1992;22:183-195. [Medline]
Torrance GW. Utility approach to measuring health-related quality of life. J Chronic Dis 1987;40:593-600. [CrossRef][Medline]
Tsevat J, Dawson NV, Matchar DB. Assessing quality of life and preferences in the seriously ill using utility theory. J Clin Epidemiol 1990;43:Suppl:73S-77S.
Kaplan EL, Meier P. Nonparametric estimation from incomplete observations. J Am Stat Assoc 1958;53:457-81.
Cox DR. Regression models and life-tables. J R Stat Soc [B] 1972;34:187-220.
Pilote L, Racine N, Hlatky MA. Differences in the treatment of myocardial infarction in the United States and Canada: a comparison of two university hospitals. Arch Intern Med 1994;154:1090-1096. [Free Full Text]
Anderson GM, Grumbach K, Luft HS, Roos LL, Mustard C, Brook R. Use of coronary artery bypass surgery in the United States and Canada: influence of age and income. JAMA 1993;269:1661-1666. [Free Full Text]
Califf, R. M.
(2009). Rational use of medications: If Canada can't do it .... CMAJ
181: 15-16
[Full Text]
Tu, J. V., Ko, D. T.
(2008). Ecological Studies and Cardiovascular Outcomes Research. Circulation
118: 2588-2593
[Full Text]
Lee, D. S., Tu, J. V., Chong, A., Alter, D. A.
(2008). Patient Satisfaction and Its Relationship With Quality and Outcomes of Care After Acute Myocardial Infarction. Circulation
118: 1938-1945
[Abstract][Full Text]
Krumholz, H. M.
(2008). Outcomes Research: Generating Evidence for Best Practice and Policies. Circulation
118: 309-318
[Full Text]
Gershlick, A H, de Belder, M, Chambers, J, Hackett, D, Keal, R, Kelion, A, Neubauer, S, Pennell, D J, Rothman, M, Signy, M, Wilde, P
(2007). Role of non-invasive imaging in the management of coronary artery disease: an assessment of likely change over the next 10 years. A report from the British Cardiovascular Society Working Group. Heart
93: 423-431
[Abstract][Full Text]
Kaul, P., Peterson, E.D.
(2007). The Cardiovascular World Is Definitely Not Flat. Circulation
115: 158-160
[Full Text]
Ko, D. T., Krumholz, H. M., Wang, Y., Foody, J. M., Masoudi, F. A., Havranek, E. P., You, J. J., Alter, D. A., Stukel, T. A., Newman, A. M., Tu, J. V.
(2007). Regional Differences in Process of Care and Outcomes for Older Acute Myocardial Infarction Patients in the United States and Ontario, Canada. Circulation
115: 196-203
[Abstract][Full Text]
Eisenberg, M. J.
(2006). The Perspective of a Canadian Practitioner in America--Reply. Arch Intern Med
166: 1421-1422
[Full Text]
Alexander, K. P., Newby, L. K., Bhapkar, M. V., White, H. D., Hochman, J. S., Pfisterer, M. E., Moliterno, D. J., Peterson, E. D., Van de Werf, F., Armstrong, P. W., Califf, R. M., for the SYMPHONY and 2nd SYMPHONY Investigators,
(2006). International variation in invasive care of the elderly with acute coronary syndromes. Eur Heart J
27: 1558-1564
[Abstract][Full Text]
Kaul, P., Chang, W.-C., Lincoff, A. M., Aylward, P., Betriu, A., Bode, C., Califf, R. M., Ohman, E. M., Guetta, V., Steg, P. G., Van de Werf, F., Armstrong, P. W.
(2006). Optimizing use of revascularization and clinical outcomes in ST-elevation myocardial infarction: insights from the GUSTO-V trial. Eur Heart J
27: 1198-1206
[Abstract][Full Text]
Ayanian, J. Z.
(2006). Rising Rates of Cardiac Procedures in the United States and Canada: Too Much of a Good Thing?. Circulation
113: 333-335
[Full Text]
Singh, M., Williams, B. A., Gersh, B. J., McClelland, R. L., Ho, K. K.L., Willerson, J. T., Penny, W. F., Cutlip, D. E., Holmes, D. R. Jr
(2006). Geographical Differences in the Rates of Angiographic Restenosis and Ischemia-Driven Target Vessel Revascularization After Percutaneous Coronary Interventions: Results From the Prevention of Restenosis With Tranilast and its Outcomes (PRESTO) Trial. J Am Coll Cardiol
47: 34-39
[Abstract][Full Text]
Ohman, E. M., Chang, P. P.
(2005). Improving Quality of Life After Cardiogenic Shock: Do More Revascularization!. J Am Coll Cardiol
46: 274-276
[Full Text]
Chang, W.-C., Midodzi, W. K, Westerhout, C. M, Boersma, E., Cooper, J., Barnathan, E. S, Simoons, M. L, Wallentin, L., Ohman, E M., Armstrong, P. W, for the GUSTO-IV ACS Investigators,
(2005). Are international differences in the outcomes of acute coronary syndromes apparent or real? A multilevel analysis. J. Epidemiol. Community Health
59: 427-433
[Abstract][Full Text]
Stukel, T. A., Lucas, F. L., Wennberg, D. E.
(2005). Long-term Outcomes of Regional Variations in Intensity of Invasive vs Medical Management of Medicare Patients With Acute Myocardial Infarction. JAMA
293: 1329-1337
[Abstract][Full Text]
Ritchie, J. L., Wolk, M. J., Hirshfeld, J. W. Jr, Messer, J. V., Peterson, E. D., Prystowsky, E. N., Gardner, T. J., Kimball, H. R., Popp, R. L., Smaha, L., Smith, S. C. Jr, Wann, L. S.
(2004). Task force 4: Appropriate clinical care and issues of "self-referral". J Am Coll Cardiol
44: 1740-1746
[Full Text]
Ritchie, J. L., Wolk, M. J., Hirshfeld, J. W. Jr, Messer, J. V., Peterson, E. D., Prystowsky, E. N., Gardner, T. J., Kimball, H. R., Popp, R. L., Smaha, L., Smith, S. C. Jr, Wann, L. S.
(2004). Task Force 4: Appropriate Clinical Care and Issues of "Self-Referral". Circulation
110: 2528-2534
[Full Text]
Kaul, P., Armstrong, P. W., Chang, W.-C., Naylor, C. D., Granger, C. B., Lee, K. L., Peterson, E. D., Califf, R. M., Topol, E. J., Mark, D. B.
(2004). Long-Term Mortality of Patients With Acute Myocardial Infarction in the United States and Canada: Comparison of Patients Enrolled in Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO)-I. Circulation
110: 1754-1760
[Abstract][Full Text]
Clarke, A. E., Petri, M., Manzi, S., Isenberg, D. A., Gordon, C., Senecal, J.-L., Penrod, J., Joseph, L., St Pierre, Y., Fortin, P. R., Sutcliffe, N., Richard Goulet, J., Choquette, D., Grodzicky, T., Esdaile, J. M.
(2004). The systemic lupus erythematosus Tri-nation Study: absence of a link between health resource use and health outcome. Rheumatology (Oxford)
43: 1016-1024
[Abstract][Full Text]
Gupta, M., Chang, W.-C., Van de Werf, F., Granger, C. B., Midodzi, W., Barbash, G., Pehrson, K., Oto, A., Toutouzas, P., Jansky, P., Armstrong, P. W., for the ASSENT II Investigators,
(2003). International differences in in-hospital revascularization and outcomes following acute myocardial infarction: A multilevel analysis of patients in ASSENT-2. Eur Heart J
24: 1640-1650
[Abstract][Full Text]
Alter, D. A., Tu, J. V., Austin, P. C., Naylor, C. D.
(2003). Waiting times, revascularization modality, and outcomes after acute myocardial infarction at hospitals with and without on-site revascularization facilities in Canada. J Am Coll Cardiol
42: 410-419
[Abstract][Full Text]
Rumsfeld, J. S., Magid, D. J., Plomondon, M. E., Sacks, J., Henderson, W., Hlatky, M., Sethi, G., Morrison, D. A., Veterans Affairs Angina With Extremely Serious Ope,
(2003). Health-related quality of life after percutaneous coronary intervention versus coronary bypass surgery in high-risk patients with medically refractory ischemia. J Am Coll Cardiol
41: 1732-1738
[Abstract][Full Text]
Klarenbach, S. W., Jacobs, P.
(2003). International Comparison of Health Resource Utilization in Subjects With Diabetes: An analysis of Canadian and American national health surveys. Diabetes Care
26: 1116-1122
[Abstract][Full Text]
Phelps, C. E.
(2003). What's Enough, What's Too Much?. ANN INTERN MED
138: 348-349
[Full Text]
Ferraris, V. A., Ferraris, S. P.
(2003). Risk Stratification and Comorbidity. Card Surg Adult
2: 187-224
[Full Text]
Khaykin, Y, Austin, P C, Tu, J V, Alter, D A
(2002). Utilisation of coronary angiography after acute myocardial infarction in Ontario over time: have referral patterns changed?. Heart
88: 460-466
[Abstract][Full Text]
Mehta, R. H., Criger, D. A., Granger, C. B., Pieper, K. K., Califf, R. M., Topol, E. J., Bates, E. R.
(2002). Patient outcomes after fibrinolytic therapy for acute myocardial infarction at hospitals with and without coronary revascularization capability. J Am Coll Cardiol
40: 1034-1040
[Abstract][Full Text]
Dzavik, V., Rouleau, J.-L. u.
(2002). Should all patients with an acute myocardial infarction present to a hospital with revascularization capabilities?: The evidence is mounting that they need not. J Am Coll Cardiol
40: 1041-1043
[Full Text]
Booth, G. L., Zinman, B., Redelmeier, D. A.
(2002). Diabetes Care in the U.S. and Canada. Diabetes Care
25: 1149-1153
[Abstract][Full Text]
Alter, D. A., Naylor, C. D., Austin, P. C., Tu, J. V.
(2002). Biology or bias: practice patterns and long-term outcomes for men and women with acute myocardial infarction. J Am Coll Cardiol
39: 1909-1916
[Abstract][Full Text]
Stewart, S., Demers, C., Murdoch, D.R., McIntyre, K., MacLeod, M.E., Kendrick, S., Capewell, S., McMurray, J.J.V.
(2002). Substantial between-hospital variation in outcome following first emergency admission for heart failure. Eur Heart J
23: 650-657
[Abstract][Full Text]
Pilote, L., Lauzon, C., Huynh, T., Dion, D., Roux, R., Racine, N., Carignan, S., Diodati, J. G., Levesque, C., Charbonneau, F., Pouliot, J., Joseph, L., Eisenberg, M. J.
(2002). Quality of Life After Acute Myocardial Infarction Among Patients Treated at Sites With and Without On-site Availability of Angiography. Arch Intern Med
162: 553-559
[Abstract][Full Text]
Cannon, C. P., Battler, A., Brindis, R. G., Cox, J. L., Ellis, S. G., Every, N. R., Flaherty, J. T., Harrington, R. A., Krumholz, H. M., Simoons, M. L., Van De Werf, F. J. J., Weintraub, W. S., Mitchell, K. R., Morrisson, S. L., Brindis, R. G., Anderson, H. V., Cannom, D. S., Chitwood, W. R. Jr, Cigarroa, J. E., Collins-Nakai, R. L., Ellis, S. G., Gibbons, R. J., Grover, F. L., Heidenreich, P. A., Khandheria, B. K., Knoebel, S. B., Krumholz, H. L., Malenka, D. J., Mark, D. B., Mckay, C. R., Passamani, E. R., Radford, M. J., Riner, R. N., Schwartz, J. B., Shaw, R. E., Shemin, R. J., Van Fossen, D. B., Verrier, E. D., Watkins, M. W., Phoubandith, D. R., Furnelli, T.
(2001). American College of Cardiology key data elements and definitions for measuring the clinical management and outcomes of patients with acute coronary syndromes: A report of the American College of Cardiology Task Force on Clinical Data Standards (Acute Coronary Syndromes Writing Committee) Endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation, American College of Emergency Physicians, American Heart Association, Cardiac Society of Australia & New Zealand, National Heart Foundation of Australia, Society for Cardiac Angiography and Interventions, and the Taiwan Society of Cardiology. J Am Coll Cardiol
38: 2114-2130
[Full Text]
Llevadot, J, Giugliano, R.P, Antman, E.M, Wilcox, R.G, Gurfinkel, E.P, Henry, T, McCabe, C.H, Charlesworth, A, Thompson, S, Nicolau, J.C, Tebbe, U, Sadowski, Z, Braunwald, E, for the InTIME II Invatigators,
(2001). Availability of on-site catheterization and clinical outcomes in patients receiving fibrinolysis for ST-elevation myocardial infarction. Eur Heart J
22: 2104-2115
[Abstract]
Giugliano, R.P, Llevadot, J, Wilcox, R.G, Gurfinkel, E.P, McCabe, C.H, Charlesworth, A, Thompson, S.L, Antman, E.M, Braunwald, E, for the In TIME II Investigators,
(2001). Geographic variation in patient and hospital characteristics, management, and clinical outcomes in ST-elevation myocardial infarction treated with fibrinolysis. Results from InTIME-II. Eur Heart J
22: 1702-1715
[Abstract]
Kokoska, E. R., Minkes, R. K., Silen, M. L., Langer, J. C., Tracy Jr, T. F., Snyder, C. L., Dillon, P. A., Weber, T. R.
(2001). Effect of Pediatric Surgical Practice on the Treatment of Children With Appendicitis. Pediatrics
107: 1298-1301
[Abstract][Full Text]
El-Kebbi, I. M., Ziemer, D. C., Cook, C. B., Miller, C. D., Gallina, D. L., Phillips, L. S.
(2001). Comorbidity and Glycemic Control in Patients With Type 2 Diabetes. Arch Intern Med
161: 1295-1300
[Abstract][Full Text]
Alter, D. A., Naylor, C. D., Austin, P. C., Tu, J. V.
(2001). Long-term MI Outcomes at Hospitals With or Without On-site Revascularization. JAMA
285: 2101-2108
[Abstract][Full Text]
Dorian, P., Jung, W., Newman, D., Paquette, M., Wood, K., Ayers, G. M., Camm, J., Akhtar, M., Luderitz, B.
(2000). The impairment of health-related quality of life in patients with intermittent atrial fibrillation: implications for the assessment of investigational therapy. J Am Coll Cardiol
36: 1303-1309
[Abstract][Full Text]
Fu, Y., Chang, W.-C., Mark, D., Califf, R. M., Mackenzie, B., Granger, C. B., Topol, E. J., Hlatky, M., Armstrong, P. W.
(2000). Canadian-American Differences in the Management of Acute Coronary Syndromes in the GUSTO IIb Trial : One-Year Follow-Up of Patients Without ST-Segment Elevation. Circulation
102: 1375-1381
[Abstract][Full Text]
Bucher, H. C, Hengstler, P., Schindler, C., Guyatt, G. H
(2000). Percutaneous transluminal coronary angioplasty versus medical treatment for non-acute coronary heart disease: meta-analysis of randomised controlled trials. BMJ
321: 73-77
[Abstract][Full Text]
Pilote, L., Lavoie, F., Ho, V., Eisenberg, M. J.
(2000). Changes in the treatment and outcomes of acute myocardial infarction in Quebec, 1988-1995. CMAJ
163: 31-36
[Abstract][Full Text]
Dodek, A.
(2000). Acute myocardial infarction in Canada: improvement with time. CMAJ
163: 41-42
[Full Text]
Higano, S.T., Gersh, B.J.
(2000). Coronary angiography and outcome following acute myocardial infarction. Eur Heart J
21: 707-709
Marrugat, J, Ferrieres, J, Masia, R, Ruidavets, J, Sala, J
(2000). Differences in use of coronary angiography and outcome of myocardial infarction in Toulouse (France) and Gerona (Spain). Eur Heart J
21: 740-746
[Abstract]
Lupon, J., Valle, V., Marrugat, J., Elosua, R., Seres, L., Pavesi, M., Freixa, R., Sanz, G., Masia, R., Molina, L., Sala, J., Serra, J., for the R.E.S.C.A.T.E. Investigators,
(1999). Six-month outcome in unstable angina patients without previous myocardial infarction according to the use of tertiary cardiologic resources. J Am Coll Cardiol
34: 1947-1953
[Abstract][Full Text]
Alter, D. A., Naylor, C. D., Austin, P., Tu, J. V.
(1999). Effects of Socioeconomic Status on Access to Invasive Cardiac Procedures and on Mortality after Acute Myocardial Infarction. NEJM
341: 1359-1367
[Abstract][Full Text]
Brophy, J. M., Joseph, L., Theroux, P.
(1999). Medical Decision Making in the Choice of a Thrombolytic Agent for Acute Myocardial Infarction. Med Decis Making
19: 411-418
Melville, M., Brown, N., Gray, D., Young, T., Hampton, J.
(1999). Outcome and use of health services four years after admission for acute myocardial infarction: case record follow up study. BMJ
319: 230-231
[Full Text]
Frances, C. D., Go, A. S., Dauterman, K. W., Deosaransingh, K., Jung, D. L., Gettner, S., Newman, J. M., Massie, B. M., Browner, W. S.
(1999). Outcome Following Acute Myocardial Infarction: Are Differences Among Physician Specialties the Result of Quality of Care or Case Mix?. Arch Intern Med
159: 1429-1436
[Abstract][Full Text]
Batchelor, W. B., Peterson, E. D., Mark, D. B., Knight, J. D., Granger, C. B., Armstrong, P. W., Califf, R. M.
(1999). A comparison of U.S. and Canadian cardiac catheterization practices in detecting severe coronary artery disease after myocardial infarction: efficiency, yield and long-term implications. J Am Coll Cardiol
34: 12-19
[Abstract][Full Text]
Scanlon, P. J., Faxon, D. P., Audet, A.-M., Carabello, B., Dehmer, G. J., Eagle, K. A., Legako, R. D., Leon, D. F., Murray, J. A., Nissen, S. E., Pepine, C. J., Watson, R. M., Ritchie, J. L., Gibbons, R. J., Cheitlin, M. D., Eagle, K. A., Gardner, T. J., Garson, A. Jr, Russell, R. O. Jr, Ryan, T. J., Smith, S. C. Jr
(1999). ACC/AHA guidelines for coronary angiography: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Coronary Angiography) developed in collaboration with the Society for Cardiac Angiography and Interventions. J Am Coll Cardiol
33: 1756-1824
[Full Text]
Mahon, N G, O'Rorke, C, Codd, M B, McCann, H A, McGarry, K, Sugrue, D D
(1999). Hospital mortality of acute myocardial infarction in the thrombolytic era. Heart
81: 478-482
[Abstract][Full Text]
Brown, N, Melville, M, Gray, D, Young, T, Munro, J, Skene, A M, Hampton, J R
(1999). Quality of life four years after acute myocardial infarction: short form 36 scores compared with a normal population. Heart
81: 352-358
[Abstract][Full Text]
Grover, S. A., Coupal, L., Paquet, S., Zowall, H.
(1999). Cost-effectiveness of 3-Hydroxy-3-Methylglutaryl-Coenzyme A Reductase Inhibitors in the Secondary Prevention of Cardiovascular Disease: Forecasting the Incremental Benefits of Preventing Coronary and Cerebrovascular Events. Arch Intern Med
159: 593-600
[Abstract][Full Text]
Tung, C. Y., Granger, C. B., Sloan, M. A., Topol, E. J., Knight, J. D., Weaver, W. D., Mahaffey, K. W., White, H., Clapp-Channing, N., Simoons, M. L., Gore, J. M., Califf, R. M., Mark, D. B.
(1999). Effects of Stroke on Medical Resource Use and Costs in Acute Myocardial Infarction. Circulation
99: 370-376
[Abstract][Full Text]
Krumholz, H. M., Chen, J., Murillo, J. E., Cohen, D. J., Radford, M. J.
(1998). Admission to Hospitals With On-Site Cardiac Catheterization Facilities : Impact on Long-Term Costs and Outcomes. Circulation
98: 2010-2016
[Abstract][Full Text]
Dakik, H. A., Kleiman, N. S., Farmer, J. A., He, Z.-X., Wendt, J. A., Pratt, C. M., Verani, M. S., Mahmarian, J. J.
(1998). Intensive Medical Therapy Versus Coronary Angioplasty for Suppression of Myocardial Ischemia in Survivors of Acute Myocardial Infarction : A Prospective, Randomized Pilot Study. Circulation
98: 2017-2023
[Abstract][Full Text]
Giugliano, R. P., Camargo, C. A. Jr, Lloyd-Jones, D. M., Zagrodsky, J. D., Alexis, J. D., Eagle, K. A., Fuster, V., O'Donnell, C. J.
(1998). Elderly Patients Receive Less Aggressive Medical and Invasive Management of Unstable Angina: Potential Impact of Practice Guidelines. Arch Intern Med
158: 1113-1120
[Abstract][Full Text]
White, H. D., Van de Werf, F. J. J.
(1998). Thrombolysis for Acute Myocardial Infarction. Circulation
97: 1632-1646
[Abstract][Full Text]
Bell, C. M., Crystal, M., Detsky, A. S., Redelmeier, D. A.
(1998). Shopping Around for Hospital Services: A Comparison of the United States and Canada. JAMA
279: 1015-1017
[Abstract][Full Text]
Glick, H. A., Polsky, D., Willke, R. J., Alves, W. M., Kassell, N., Schulman, K.
(1998). Comparison of the Use of Medical Resources and Outcomes in the Treatment of Aneurysmal Subarachnoid Hemorrhage Between Canada and the United States. Stroke
29: 351-358
[Abstract][Full Text]
BROPHY, J M, SLEIGHT, P
(1998). Enthusiasm, reality, and cost-effectiveness analysis. Heart
79: 9-10
[Full Text]
Every, N. R., Parsons, L. S., Fihn, S. D., Larson, E. B., Maynard, C., Hallstrom, A. P., Martin, J. S., Weaver, W. D., Investigators, f. t. M.
(1997). Long-term Outcome in Acute Myocardial Infarction Patients Admitted to Hospitals With and Without On-site Cardiac Catheterization Facilities. Circulation
96: 1770-1775
[Abstract][Full Text]
Tu, J. V., Pashos, C. L., Naylor, C. D., Chen, E., Normand, S.-L., Newhouse, J. P., McNeil, B. J.
(1997). Use of Cardiac Procedures and Outcomes in Elderly Patients with Myocardial Infarction in the United States and Canada. NEJM
336: 1500-1505
[Abstract][Full Text]
Selby, J. V., Fireman, B. H., Lundstrom, R. J., Swain, B. E., Truman, A. F., Wong, C. C., Froelicher, E. S., Barron, H. V., Hlatky, M. A.
(1996). Variation among Hospitals in Coronary-Angiography Practices and Outcomes after Myocardial Infarction in a Large Health Maintenance Organization. NEJM
335: 1888-1896
[Abstract][Full Text]
Dakik, H. A., Mahmarian, J. J., Kimball, K. T., Koutelou, M. G., Medrano, R., Verani, M. S.
(1996). Prognostic Value of Exercise 201Tl Tomography in Patients Treated With Thrombolytic Therapy During Acute Myocardial Infarction. Circulation
94: 2735-2742
[Abstract][Full Text]
Naylor, C. D., Jollis, J. G., Califf, R. M.
(1996). Left Main Stenosis. Ann. Thorac. Surg.
62: 1239-1241
[Full Text]
Eisenstein, E. L., Mark, D. B., Califf, R. M.
(1996). Importance of Cost and Quality of Life in Decisions About Routine Angiography After Acute Myocardial Infarction: The Role of Cost-effectiveness Models. Circulation
94: 869-871
[Full Text]
Wachter, R. M., Goldman, L.
(1996). The Emerging Role of "Hospitalists" in the American Health Care System. NEJM
335: 514-517
[Full Text]
Welch, W. P., Verrilli, D., Katz, S. J., Latimer, E.
(1996). A Detailed Comparison of Physician Services for the Elderly in the United States and Canada. JAMA
275: 1410-1416
[Abstract]
Evans, J. G.
(1996). Health Care for Older People: A Look Across a Frontier. JAMA
275: 1449-1450
[Abstract]
Naylor, C. D., Guyatt, G. H., Evidence-Based Medicine Working Group, , Bass, E., Gerstein, H., Heyland, D., Holbrook, A., Moyer, V., Newman, T., Oxman, A., Richardson, W. S., Tugwell, P., Williams, J. Jr
(1996). Users' Guides to the Medical Literature: X. How to Use an Article Reporting Variations in the Outcomes of Health Services. JAMA
275: 554-558
[Abstract]
Grover, F. L.
(1996). The Bright Future of Cardiothoracic Surgery in the Era of Changing Healthcare Delivery. Ann. Thorac. Surg.
61: 499-510
[Abstract][Full Text]
Paone, G., Higgins, R. S.D., Spencer, T., Silverman, N. A.
(1995). Enrollment in the Health Alliance Plan HMO Is Not an Independent Risk Factor for Coronary Artery Bypass Graft Surgery. Circulation
92: 69-72
[Abstract][Full Text]
Topol, E. J., Nissen, S. E.
(1995). Our Preoccupation With Coronary Luminology : The Dissociation Between Clinical and Angiographic Findings in Ischemic Heart Disease. Circulation
92: 2333-2342
[Abstract][Full Text]
Pilote, L., Califf, R. M., Sapp, S., Miller, D. P., Mark, D. B., Weaver, W. D., Gore, J. M., Armstrong, P. W., Ohman, E. M., Topol, E. J., The GUSTO-1 Investigators,
(1995). Regional Variation across the United States in the Management of Acute Myocardial Infarction. NEJM
333: 565-572
[Abstract][Full Text]
Guadagnoli, E., Hauptman, P. J., Ayanian, J. Z., Pashos, C. L., McNeil, B. J., Cleary, P. D.
(1995). Variation in the Use of Cardiac Procedures after Acute Myocardial Infarction. NEJM
333: 573-578
[Abstract][Full Text]
Gore, J. M., Dalen, J. E.
(1995). Cardiovascular Disease. JAMA
273: 1662-1664
[Abstract]
Mark, D. B., Hlatky, M. A., Califf, R. M., Naylor, C. D., Lee, K. L., Armstrong, P. W., Barbash, G., White, H., Simoons, M. L., Nelson, C. L., Clapp-Channing, N., Knight, J. D., Harrell, F. E., Simes, J., Topol, E. J.
(1995). Cost Effectiveness of Thrombolytic Therapy with Tissue Plasminogen Activator as Compared with Streptokinase for Acute Myocardial Infarction. NEJM
332: 1418-1424
[Abstract][Full Text]
Bassan, M., Doherty, N., Brophy, J.M., Joseph, L., Vajo, Z., Margoshes, B., Deckelbaum, L. I., Greenfield, S., Kaplan, S., Mark, D. B., Naylor, C. D., Armstrong, P. W.
(1995). Quality of Life after Myocardial Infarction: Canada versus the United States. NEJM
332: 469-472
[Full Text]
(1995). MI Care in the U.S. and Canada: Outcomes at One Year. Journal Watch Cardiology
1995: 3-3
[Full Text]
Kassirer, J. P.
(1994). Access to Specialty Care. NEJM
331: 1151-1153
[Full Text]
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