The joint contribution of sex, age and type of myocardial infarction on hospital mortality following acute myocardial infarction.

OBJECTIVE: Younger, but not older, women have a higher mortality than men of similar age after a myocardial infarction (MI). We sought to determine whether this relationship is true for both ST elevation MI (STEMI) and non-ST elevation MI (NSTEMI). DESIGN: Retrospective cohort study. SETTING: 1057 USA hospitals participant in the National Registry of Myocardial Infarction between 2000 and 2006. PATIENTS: 126 172 STEMI and 235 257 NSTEMI patients. MAIN OUTCOME MEASURE: Hospital death. RESULTS: For both STEMI and NSTEMI, the younger the patient's age, the greater the excess mortality risk for women compared with men, while older women fared similarly (STEMI) or better (NSTEMI) than men (p<0.0001 for the age-sex interaction). In STEMI, the unadjusted women-to-men RR was 1.68 (95% CI 1.41 to 2.01), 1.78 (1.59 to 1.99), 1.45 (1.34 to 1.57), 1.08 (1.02 to 1.14) and 1.03 (0.98 to 1.07) for age <50 years, age 50-59, age 60-69, age 70-79 and age 80-89, respectively. For NSTEMI, corresponding unadjusted RRs were 1.56 (1.31 to 1.85), 1.42 (1.27 to 1.58), 1.17 (1.09 to 1.25), 0.92 (0.88 to 0.96) and 0.86 (0.83 to 0.89). After adjusting for risk status, the excess risk for younger women compared with men decreased to approximately 15-20%, while a better survival of older NSTEMI women compared with men persisted. CONCLUSIONS: Sex-related differences in short-term mortality are age-dependent in both STEMI and NSTEMI patients.

Ischaemic symptoms, quality of care and mortality during myocardial infarction.

OBJECTIVE: To study in myocardial infarction (MI) whether documentation of ischaemic symptoms is associated with quality of care and outcomes, and to compare patient reports of ischaemic symptoms during interviews with chart documentation. DESIGN: Observational acute MI study from 2003 to 2004 (Prospective Registry Evaluating Myocardial Infarction: Event and Recovery). SETTING: 19 diverse US hospitals. PATIENTS: 2094 consecutive patients with MI (10 911 patients screened; 3953 patients were eligible and enrolled) with both positive cardiac enzymes and other evidence of infarction (eg, symptoms, electrocardiographic changes). Transferred patients and those with confounding non-cardiac comorbidity were not included (n = 1859). MAIN OUTCOME MEASURES: Quality of care indicators and adjusted in-hospital survival. RESULTS: The records of 10% of all patients with MI (217/2094) contained no documented ischaemic symptoms at presentation. Patients without documented symptoms were less likely (p<0.05) to receive aspirin (89% vs 96%) or beta-blockers (77% vs 90%) within 24 hours, reperfusion therapy for ST-elevation MI (7% vs 58%) or to survive their hospitalisation (adjusted odds ratio = 3.2, 95% CI 1.8 to 5.8). Survivors without documented symptoms were also less likely (p<0.05) to be discharged with aspirin (87% vs 93%), beta-blockers (81% vs 91%), ACE/ARB (67% vs 80%), or smoking cessation counselling (46% vs 66%). In the subset of 1356 (65%) interviewed patients, most of those without documented ischaemic symptoms (75%) reported presenting symptoms consistent with ischaemia. CONCLUSIONS: Failure to document patients' presenting MI symptoms is associated with poorer quality of care from admission to discharge, and higher in-hospital mortality. Symptom recognition may represent an important opportunity to improve the quality of MI care.

Hormone therapy and in-hospital survival after myocardial infarction in postmenopausal women.

BACKGROUND: Although postmenopausal hormone therapy (HRT) commonly is used in hope of preventing coronary heart disease, the effect of HRT on case fatality of myocardial infarction has never been studied. We evaluated HRT as a predictor of survival after MI in postmenopausal women. METHODS AND RESULTS: The present study was performed with 114 724 women of age >/=55 years with confirmed myocardial infarction who presented between April 1998 and January 2000 to 1 of 1674 hospitals participating in the National Registry of Myocardial Infarction-3. Presenting characteristics, treatment, and clinical outcome data were obtained by chart review. At time of hospitalization, 7353 (6.4%) women reported current use of HRT, defined as use of estrogen, progestin, or estrogen/progestin for reasons other than contraception. Unadjusted mortality was 7.4% in users of HRT and 16.2% in nonusers (odds ratio 0.41, 95% confidence interval 0.36 to 0.43). After adjustments were made for prior medical history, clinical characteristics, treatments received in-hospital, and likelihood of receiving HRT, HRT remained associated with an improved rate of survival (odds ratio 0.65, 95% confidence interval 0.59 to 0.72). Significant association of HRT with decreased mortality after myocardial infarction was observed in all age strata. CONCLUSIONS: Postmenopausal HRT appears to be associated with reduced mortality after myocardial infarction. This finding could be caused by therapeutic effect of HRT, selection and adherence bias, or some combination of both.

Hormone therapy and the risk of stroke after acute myocardial infarction in postmenopausal women.

OBJECTIVES: We examined the association of hormone therapy (HRT) with hemorrhagic and ischemic stroke among postmenopausal women with acute myocardial infarction (AMI). BACKGROUND: Hemorrhagic and ischemic strokes are common complications of AMI, and women are at increased risk for hemorrhagic stroke after thrombolytic therapy. This risk may be related to female hormones. METHODS: Using data from the National Registry of Myocardial Infarction-3, we studied 114,724 women age 55 years or older admitted to the hospital for AMI, of whom 7,353 reported HRT use on admission. We determined rates of in-hospital hemorrhagic and ischemic stroke stratified by HRT use and estimated the independent association of HRT with each stroke type using multivariable logistic regression. RESULTS: The HRT users were younger than non-users, had fewer risk factors for stroke including diabetes and prior stroke, and received more pharmacologic and invasive therapy including cardiac catheterization. A total of 2,152 (1.9%) in-hospital strokes occurred, with 442 (0.4%) hemorrhagic, 1,017 (0.9%) ischemic and 693 (0.6%) unspecified. Among HRT users and non-users, the rates of hemorrhagic stroke (0.40% vs. 0.42%, p = 1.00) and ischemic stroke (0.80% vs. 0.96%, p = 0.11) were similar. Among 13,328 women who received thrombolytic therapy, the rate of hemorrhagic stroke was not significantly different for users and non-users (1.6% vs. 2.1%, p = 0.22). After adjustment for baseline and treatment differences, HRT was not associated with hemorrhagic (odds ratio [OR], 0.88; 95% confidence intervals [CI], 0.58 to 1.35) or ischemic stroke (OR, 0.89; CI, 0.66 to 1.18). CONCLUSIONS: Acute myocardial infarction is a high-risk setting for stroke among postmenopausal women, but HRT does not appear to modify that risk. Clinicians should not alter their approach to thrombolytic therapy based on HRT use.

Underutilization of reperfusion therapy in eligible African Americans with acute myocardial infarction: Role of presentation and evaluation characteristics.

BACKGROUND: Immediate reperfusion therapy to restore coronary blood flow is recommended for all eligible patients with acute myocardial infarction. However, reperfusion therapy is reportedly underutilized among African Americans, even when they are eligible. Reasons for the lack of use have not been fully explored. METHODS: We examined the demographic, clinical, and treatment data of 10,469 African Americans with acute myocardial infarction who were eligible for reperfusion therapy, enrolled in the National Registry of Myocardial Infarction-2 from June 1994 through March 1998. RESULTS: The mean age was 62.58 (+/-14.4) years, and 44.7% were female. Although eligible, 47% of the African Americans in this study did not receive reperfusion therapy. In a multivariate analysis, the absence of chest pain at presentation (odds ratio [OR] 0.31, 95% CI 0.26-0.37) and initial admission diagnoses other than definite myocardial infarction (OR for receipt of reperfusion <0.12) were the strongest predictors of lack of early reperfusion therapy. Progressive delays in hospital arrival and hospital evaluation predicted a lower likelihood of early reperfusion. Prior stroke (OR 0.63, 95% CI 0.50-0.78), myocardial infarction (OR 0.75, 95% CI 0.65-0.86), and congestive heart failure (OR 0.49, 95% CI 0.40-0.60) were all associated with lack of reperfusion therapy. CONCLUSION: Almost half of eligible African American patients with myocardial infarction did not receive reperfusion therapy. Potential reasons may include atypical presentation, patient and institutional delay, and underappreciation of myocardial infarction by care providers. Strategies to address these factors may improve the rate of use of reperfusion therapy.

Use of reperfusion therapies in elderly patients with acute myocardial infarction.

Almost one-third of patients with acute myocardial infarction (AMI) are aged >75 years, and this proportion is expected to increase as the population ages. Mortality and complication rates are particularly high in the elderly, yet reperfusion therapies, including thrombolysis and primary percutaneous transluminal coronary angioplasty (PTCA), are under-utilised among eligible patients. There is a concern, whether real or perceived, that the risks of such therapies may outweigh the potential benefits. Presently, there are no randomised clinical trials of thrombolytic therapy in the elderly that definitively assess its efficacy in patients aged >75 years. In the meta-analysis of randomised trials by the Fibrinolytic Therapy Trialists, thrombolysis was associated with a mortality reduction among patients aged >75 years, though this reduction did not meet formal statistical significance. Because the point estimates for mortality reduction were in the direction that favoured use of thrombolytic therapy, the American Heart Association/American College of Cardiology AMI guidelines recommend thrombolysis as a Class 2a therapy in this age group. Observational studies using data from the Cooperative Cardiovascular Project database and the National Registry of Myocardial Infarction have recently cast some doubt on the benefit of thrombolysis among the elderly, but definitive answers from a randomised trial are still lacking. Meanwhile, primary PTCA, which has been compared to thrombolysis in both trial and observational settings, appears to offer the mortality benefit of reperfusion with lower stroke rates. Since primary PTCA is not widely available, efforts must be made to maximise available therapies in the elderly. Early diagnosis is essential, as is prompt reperfusion among eligible patients, since delay is so strongly associated with mortality with both thrombolysis and PTCA. Finally, newer, more fibrin-specific thrombolytics may decrease the bleeding risk associated with thrombolytic therapy.

Temporal trends in the treatment of over 1.5 million patients with myocardial infarction in the US from 1990 through 1999: the National Registry of Myocardial Infarction 1, 2 and 3.

OBJECTIVES: We sought to determine trends in the treatment of myocardial infarction from 1990 through 1999 in the U.S. and to relate these trends to current guidelines. BACKGROUND: Limited data are available to show how recent clinical trials and clinical guidelines have impacted treatment of myocardial infarction. METHODS: Temporal trends in myocardial infarction treatment and outcome were assessed by using data from 1,514,292 patients in the National Registry of Myocardial Infarction (NRMI) 1, 2 and 3 from 1990 through 1999. RESULTS: During this interval, the use of intravenous thrombolytic therapy declined from 34.3% to 20.8%, but the use of primary angioplasty increased from 2.4% to 7.3% (both p = 0.0001). The median "door-to-drug" time among thrombolytic therapy recipients fell from 61.8 to 37.8 min (p = 0.0001), primarily owing to shorter "door-to-data" and "data-to-decision" times. The prevalence of non-Q wave infarctions increased from 45% in 1994 to 63% in 1999 (p = 0.0001). From 1994 through 1999, there was increased usage of beta-blockers, aspirin and angiotensin-converting inhibitors, both during the first 24 h after admission and on hospital discharge (all p = 0.0001). Between 1990 and 1999, the median duration of hospital stay fell from 8.3 to 4.3 days, and hospital mortality declined from 11.2% to 9.4% (both p = 0.0001). CONCLUSIONS: The NRMI data from 1990 through 1999 demonstrate that the recommendations of recent clinical trials and published guidelines are being implemented, resulting in more rapid administration of intravenous thrombolytic therapy, increasing use of primary angioplasty and more frequent use of adjunctive therapies known to reduce mortality, and may be contributing to the higher prevalence of non-Q wave infarctions, shorter hospital stays and lower hospital mortality.

Treatment and outcomes of left bundle-branch block patients with myocardial infarction who present without chest pain. National Registry of Myocardial Infarction 2 Investigators.

OBJECTIVES: We sought to determine the importance of chest pain on presentation as a predictor of in-hospital treatment and mortality in myocardial infarction (MI) patients with left bundle-branch block (LBBB). BACKGROUND: Left bundle-branch block patients have a high mortality after MI but are unlikely to receive reperfusion therapy despite evidence from clinical trials demonstrating the efficacy of thrombolytic therapy. Nearly half of MI patients with LBBB present without chest pain. METHODS: We studied the clinical features, treatment and in-hospital survival of 29,585 patients with LBBB enrolled in the National Registry of MI 2 June 1994 through March 1998). Multivariate logistic regression was used to assess the independent effect of chest pain on reperfusion decisions and in-hospital mortality. RESULTS: Left bundle-branch block patients with chest pain were greater than five-fold more likely to receive reperfusion therapy (13.6% vs. 2.6%) than LBBB patients without chest pain; they were also more likely to receive aspirin, beta-adrenergic blocking agents, heparin and nitrates (all p < 0.0001). Unadjusted in-hospital mortality was 18% in patients with chest pain and 27% in patients without chest pain. Adjusting for patient characteristics reduced the odds ratio associated with the absence of chest pain from 1.47 (95% confidence interval: 1.41 to 1.54) to 1.21 (95% confidence interval: 1.12 to 1.30). The remainder of the mortality difference was caused by the undertreatment of patients without chest pain, particularly the low utilization of aspirin and beta-blockers. CONCLUSIONS: Left bundle-branch block patients with MI who present without chest pain are less likely to receive optimal therapy and are at increased risk of death. Prompt recognition and treatment of this high-risk subgroup should improve survival.

Relationship of hospital teaching status with quality of care and mortality for Medicare patients with acute MI.

CONTEXT: Issues of cost and quality are gaining importance in the delivery of medical care, and whether quality of care is better in teaching vs nonteaching hospitals is an essential question in this current national debate. OBJECTIVE: To examine the association of hospital teaching status with quality of care and mortality for fee-for-service Medicare patients with acute myocardial infarction (AMI). DESIGN, SETTING, AND PATIENTS: Analysis of Cooperative Cardiovascular Project data for 114,411 Medicare patients from 4361 hospitals (22,354 patients from 439 major teaching hospitals, 22,493 patients from 455 minor teaching hospitals, and 69,564 patients from 3467 nonteaching hospitals) who had AMI between February 1994 and July 1995. MAIN OUTCOME MEASURES: Administration of reperfusion therapy on admission, aspirin during hospitalization, and beta-blockers and angiotensin-converting enzyme inhibitors at discharge for patients meeting strict inclusion criteria; mortality at 30, 60, and 90 days and 2 years after admission. RESULTS: Among major teaching, minor teaching, and nonteaching hospitals, respectively, administration rates for aspirin were 91.2%, 86.4%, and 81.4% (P<.001); for angiotensin-converting enzyme inhibitors, 63. 7%, 60.0%, and 58.0% (P<.001); for beta-blockers, 48.8%, 40.3%, and 36.4% (P<.001); and for reperfusion therapy, 55.5%, 58.9%, and 55.2% (P =.29). Differences in unadjusted 30-day, 60-day, 90-day, and 2-year mortality among hospitals were significant at P<.001 for all time periods, with a gradient of increasing mortality from major teaching to minor teaching to nonteaching hospitals. Mortality differences were attenuated by adjustment for patient characteristics and were almost eliminated by additional adjustment for receipt of therapy. CONCLUSIONS: In this study of elderly patients with AMI, admission to a teaching hospital was associated with better quality of care based on 3 of 4 quality indicators and lower mortality. JAMA. 2000;284:1256-1262

Prevalence, clinical characteristics, and mortality among patients with myocardial infarction presenting without chest pain.

CONTEXT: Although chest pain is widely considered a key symptom in the diagnosis of myocardial infarction (MI), not all patients with MI present with chest pain. The extent to which this phenomenon occurs is largely unknown. OBJECTIVES: To determine the frequency with which patients with MI present without chest pain and to examine their subsequent management and outcome. DESIGN: Prospective observational study. SETTING AND PATIENTS: A total of 434,877 patients with confirmed MI enrolled June 1994 to March 1998 in the National Registry of Myocardial Infarction 2, which includes 1674 hospitals in the United States. MAIN OUTCOME MEASURES: Prevalence of presentation without chest pain; clinical characteristics, treatment, and mortality among MI patients without chest pain vs those with chest pain. RESULTS: Of all patients diagnosed as having MI, 142,445 (33%) did not have chest pain on presentation to the hospital. This group of MI patients was, on average, 7 years older than those with chest pain (74.2 vs 66.9 years), with a higher proportion of women (49.0% vs 38.0%) and patients with diabetes mellitus (32.6% vs 25. 4%) or prior heart failure (26.4% vs 12.3%). Also, MI patients without chest pain had a longer delay before hospital presentation (mean, 7.9 vs 5.3 hours), were less likely to be diagnosed as having confirmed MI at the time of admission (22.2% vs 50.3%), and were less likely to receive thrombolysis or primary angioplasty (25.3% vs 74.0%), aspirin (60.4% vs 84.5%), beta-blockers (28.0% vs 48.0%), or heparin (53.4% vs 83.2%). Myocardial infarction patients without chest pain had a 23.3% in-hospital mortality rate compared with 9.3% among patients with chest pain (adjusted odds ratio for mortality, 2. 21 [95% confidence interval, 2.17-2.26]). CONCLUSIONS: Our results suggest that patients without chest pain on presentation represent a large segment of the MI population and are at increased risk for delays in seeking medical attention, less aggressive treatments, and in-hospital mortality. JAMA. 2000;283:3223-3229

The volume of primary angioplasty procedures and survival after acute myocardial infarction. National Registry of Myocardial Infarction 2 Investigators.

BACKGROUND: There is an inverse relation between mortality from cardiovascular causes and the number of elective cardiac procedures (coronary angioplasty, stenting, or coronary bypass surgery) performed by individual practitioners or hospitals. However, it is not known whether patients with acute myocardial infarction fare better at centers where more patients undergo primary angioplasty or thrombolytic therapy than at centers with lower volumes. METHODS: We analyzed data from the National Registry of Myocardial Infarction to determine the relation between the number of patients receiving reperfusion therapy (primary angioplasty or thrombolytic therapy) and subsequent in-hospital mortality. A total of 450 hospitals were divided into quartiles according to the volume of primary angioplasty. Multiple logistic-regression models were used to determine whether the volume of primary angioplasty procedures was an independent predictor of in-hospital mortality among patients undergoing this procedure. Similar analyses were performed for patients receiving thrombolytic therapy at 516 hospitals. RESULTS: In-hospital mortality was 28 percent lower among patients who underwent primary angioplasty at hospitals with the highest volume than among those who underwent angioplasty at hospitals with the lowest volume (adjusted relative risk, 0.72; 95 percent confidence interval, 0.60 to 0.87; P<0.001). This lower rate, which represented 2.0 fewer deaths per 100 patients treated, was independent of the total volume of patients with myocardial infarction at each hospital, year of admission, and use or nonuse of adjunctive pharmacologic therapies. There was no significant relation between the volume of thrombolytic interventions and in-hospital mortality among patients who received thrombolytic therapy (7.0 percent for patients in the highest-volume hospitals vs. 6.9 percent for those in the lowest-volume hospitals, P=0.36). CONCLUSIONS: Among hospitals in the United States that have full interventional capabilities, a higher volume of angioplasty procedures is associated with a lower mortality rate among patients undergoing primary angioplasty, but there is no association between volume and mortality for thrombolytic therapy.

Relation of race and sex to the use of reperfusion therapy in Medicare beneficiaries with acute myocardial infarction.

BACKGROUND: There are few reports describing the combined influence of the race and sex of a patient on the use of reperfusion therapy for acute myocardial infarction. METHODS: To determine the relation of race and sex to the receipt of reperfusion therapy for myocardial infarction in the United States, we reviewed the medical records of 234,769 Medicare patients with myocardial infarction. From these records we identified 26,575 white or black patients who met strict eligibility criteria for reperfusion therapy. We then performed bivariate and multivariate analyses of prevalence ratios to determine predictors of the use of reperfusion therapy in four subgroups of patients categorized according to race and sex: white men, white women, black men, and black women. RESULTS: Among eligible patients, white men received reperfusion therapy with the highest frequency (59 percent), followed by white women (56 percent), black men (50 percent), and black women (44 percent). After adjustment for differences in demographic and clinical characteristics, white women were as likely as white men to receive reperfusion therapy (prevalence ratio, 1.00; 95 percent confidence interval, 0.98 to 1.03). Likewise, black women were as likely as black men to receive reperfusion therapy (prevalence ratio, 1.00; 95 percent confidence interval, 0.89 to 1.13). However, black women were significantly less likely to receive reperfusion therapy than white men (prevalence ratio, 0.90; 95 percent confidence interval, 0.82 to 0.98), as were black men (prevalence ratio, 0.85; 95 percent confidence interval, 0.78 to 0.93). CONCLUSIONS: After adjustment for differences in clinical and demographic characteristics and clinical presentation, differences according to sex in the use of reperfusion therapy are minimal. However, blacks, regardless of sex, are significantly less likely than whites to receive this potentially lifesaving therapy.

Payer status and the utilization of hospital resources in acute myocardial infarction: a report from the National Registry of Myocardial Infarction 2.

BACKGROUND: Prior studies have suggested that payer status may be an important determinant of medical resource utilization and outcome in acute myocardial infarction (AMI). METHODS: A national cohort of 332,221 patients with AMI enrolled from June 1994 to July 1996 were compared within 5 payer groups to ascertain the influence of payer status on hospital resource allocation for AMI in the United States. RESULTS: Medicare comprised the largest proportion (56%), followed by commercial insurance (25%), health maintenance organization (HMO) (10%), uninsured (6%), and Medicaid (3%). Compared with commercially insured patients, Medicare and Medicaid patients received fewer reperfusion therapies, underwent fewer invasive cardiac procedures, and had longer hospitalizations. After adjusting for differences in clinical characteristics, Medicare recipients were as likely as commercially insured patients to receive acute reperfusion therapies or any invasive cardiac procedure. Uninsured and HMO patients tended to utilize hospital resources with intermediate frequency. Medicare recipients aged 65 years or older and the HMO group had similar hospital mortality rates compared with the commercial group (odds ratio [OR], 1.07; 95% confidence interval [CI], 0.96-1.20 and OR, 0.93; 95% CI, 0.83-1.04, respectively), but Medicaid and uninsured groups had higher hospital mortality rates compared with the commercial group (OR, 1.30; 95% CI, 1.14-1.48 and OR, 1.29; 95% CI, 1.12-1.48, respectively). CONCLUSION: This report suggests significant variation by payer status in the management of AMI throughout the United States, but no important differences in mortality among the 3 largest payer groups.

Treatment and outcome of myocardial infarction in hospitals with and without invasive capability. Investigators in the National Registry of Myocardial Infarction.

OBJECTIVES: We sought to determine the extent to which the capability of a hospital to perform invasive cardiovascular procedures influences treatment and outcome of patients admitted with acute myocardial infarction (AMI). BACKGROUND: Patients with AMI are usually transported to the closest hospital. However, relatively few hospitals have the capability for immediate coronary arteriography, percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass graft surgery (CABG), should these interventions be needed. METHODS: The 1,506 hospitals participating in the National Registry of Myocardial Infarction 2 were classified according to their highest level of invasive capability: 1) none (noninvasive, 28.1%); 2) coronary arteriography (cath-capable, 25.2%); 3) coronary angioplasty (PTCA-capable, 7.4%); and 4) bypass surgery (CABG-capable, 39.2%). Treatment and in-hospital outcomes were assessed for 305,812 patients admitted from June 1994 through October 1996. Follow-up through 90 days was ascertained in a subset of 30,402 patients enrolled simultaneously in both the National Registry of Myocardial Infarction (NRMI) 2 and the Cooperative Cardiovascular Project (CCP). RESULTS: The proportion of patients receiving initial reperfusion intervention was only slightly higher at the more invasive hospitals (noninvasive 32.5%, cath-capable 31.2%, PTCA-capable 32.9% and CABG-capable 35.9%, p < 0.001 by chi-square statistic). Among thrombolytic recipients, median door-to-drug time interval differed little among hospital types and ranged from 42 to 45 minutes. At cath-capable, PTCA-capable and CABG-capable hospitals, coronary arteriography was performed in 32.9%, 37.4% and 64.9%, respectively, and PTCA in 0.0%, 5.1% and 31.4%, both p < 0.001 by chi-square statistic. The proportion of patients transferred out to other facilities was 51.0%, 42.2%, 39.9% and 4.4% (p < 0.0001) among noninvasive, cath-capable, PTCA-capable and CABG-capable hospitals, respectively. Among patients in the combined NRMI and CCP data set, mortality at 90 days postinfarction was similar among patients initially admitted to each of the four hospital types. CONCLUSIONS: Although patients with AMI admitted to hospitals without invasive cardiac facilities have a high likelihood of subsequent transfer to other facilities, their likelihood of receiving a reperfusion intervention at the first hospital, their door to thrombolytic drug intervals and their 90-day survival rates are similar to those of patients initially admitted to more invasively equipped hospitals. These data suggest that a policy of initial treatment of myocardial infarction at the closest medical facility is appropriate medical practice.

Relation between hospital primary angioplasty volume and mortality for patients with acute MI treated with primary angioplasty vs thrombolytic therapy.

CONTEXT: Institutional experience with primary angioplasty has been suggested as a factor in selecting a reperfusion strategy for patients with acute myocardial infarction (AMI). However, no large studies have directly compared outcomes of primary angioplasty vs thrombolytic therapy as a function of institutional experience. OBJECTIVE: To compare outcomes among patients with AMI who were treated with primary angioplasty vs thrombolytic therapy at hospitals with different volumes of primary angioplasty. DESIGN: Retrospective cohort. SETTING: A total of 446 acute care hospitals with 112 classified as low volume (/=49 procedures) based on their annual primary angioplasty volume. PATIENTS: A total of 62 299 patients with AMI treated with primary angioplasty or thrombolytic therapy from June 1, 1994, through July 31, 1999. MAIN OUTCOME MEASURE: In-hospital mortality. RESULTS: Mortality was lower among patients who received primary angioplasty compared with those who received thrombolysis at hospitals with intermediate volumes (4.5% vs 5.9%; P<.001) and high volumes (3.4% vs 5.4%; P<.001) of primary angioplasty. At low-volume hospitals, there was no significant difference in mortality between patients treated with primary angioplasty vs those treated with thrombolysis (6.2% vs 5.9%; P =.58). Adjusting for differences in demographic, medical history, clinical presentation, treatment, and hospital characteristics did not significantly alter these findings. CONCLUSIONS: In this study, patients with AMI treated at hospitals with high or intermediate volumes of primary angioplasty had lower mortality with primary angioplasty than with thrombolysis, whereas patients with AMI treated at hospitals with low angioplasty volumes had similar mortality outcomes with primary angioplasty or thrombolysis.

Comparison of outcomes research with clinical trials using preexisting data.

Outcomes research using analysis of preexisting data is a relatively new field with the potential to improve the quality and effectiveness of medical care, and may provide a useful complement to randomized studies. Motivated by the growth of this research in the cardiovascular literature, this review offers a framework to identify the core concepts of outcomes research from database analyses by comparing and contrasting it with the randomized clinical trial.

The association between the on-site availability of cardiac procedures and the utilization of those services for acute myocardial infarction by payer group. The National Registry of Myocardial Infarction 2 Investigators.

BACKGROUND: Prior studies have suggested that in-hospital availability may be an important determinant for the use of invasive cardiac services; however, whether this association is influenced by payer status remains unclear. HYPOTHESIS: The interaction of payer status and the on-site availability of coronary arteriography is associated with increased utilization of this procedure. METHODS: In-hospital availability and utilization of coronary arteriography was ascertained in 275,046 patients with acute myocardial infarction (AMI) enrolled in the National Registry of Myocardial Infarction 2 from June 1994 to April 1996. Logistic regression analyses were performed to determine the association between the on-site availability of cardiac catheterization at the initial hospital and subsequent utilization of coronary arteriography. Similar analyses were performed within Medicare, Medicaid, Commercial, Health Maintenance Organization (HMO), and Uninsured payer groups. RESULTS: Patients initially admitted to hospitals having on-site cardiac catheterization facilities were almost twice as likely to receive coronary arteriography as patients admitted to hospitals without such facilities and later transferred out [un-adjusted odds ratio (OR) = 1.69, 95% confidence interval (CI) 1.66-1.73, p < 0.0001; adjusted OR = 2.08, 95% CI 2.01-2.15, p < 0.0001]. Furthermore, this relationship of increased utilization with greater availability was evident within each payer group, but was highest among those with Commercial insurance and lowest among Medicaid recipients: [Commercial insurance (OR = 2.19, 95% CI 2.07-2.31, p < 0.0001); Uninsured (OR = 1.74, 95% CI 1.57-1.92, p < 0.0001); HMO (OR = 1.67, 95% CI 1.54-1.82, p < 0.0001); Medicare 1.60, 95% CI 1.55-1.64, p < 0.0001); Medicaid (1.46, 95% CI 1.29-1.65, p < 0.0001)]. CONCLUSIONS: Our results show a strong association between in-hospital availability and subsequent utilization of invasive cardiac procedures following AMI among all patients, but the strength of these associations varied among payer status.

Presenting characteristics, treatment patterns, and clinical outcomes of non-black minorities in the National Registry of Myocardial Infarction 2.

Data from a national registry (cohort) of myocardial infarction, which has enrolled 275,046 patients from June 1994 to April 1996, were analyzed to compare the baseline demographic and clinical characteristics, treatment patterns, and clinical outcomes among Hispanics, Asian-Pacific islanders, and native Americans with those of white Americans presenting to the hospital with acute myocardial infarction. Non-black minorities were younger, had a higher proportion of men, used the emergency medical services less frequently, and presented later to the hospital after the onset of symptoms (135 vs 122 minutes, p <0.001) than whites. Also, non-black minorities were less likely to receive beta-blocker therapy at discharge (crude odds ratio 0.86, confidence interval 0.82 to 0.90) than whites, but they were generally as likely to receive intravenous thrombolytic therapy (with the exception of Asian-Pacific islanders) and undergo both coronary arteriography and revascularization procedures as their white counterparts. There were no significant differences in hospital mortality for non-black minorities compared with whites.

Management and outcomes for black patients with acute myocardial infarction in the reperfusion era. National Registry of Myocardial Infarction 2 Investigators.

Data from a national registry of myocardial infarction patients from June 1994 to April 1996 were analyzed to compare the presenting characteristics, acute reperfusion strategies, treatment patterns, and clinical outcomes among black and white patients. Blacks presented much later to the hospital after the onset of symptoms (median 145 vs 122 minutes, p <0.001), were more likely to have atypical cardiac symptoms (28% vs 24%, p <0.001), and nondiagnostic electrocardiograms during the initial evaluation period compared with whites (37% vs 31%, p <0.001). Also, blacks were less likely to receive intravenous thrombolytic therapy (adjusted odds ratio [OR] 0.76, 95% confidence intervals [CI] 0.71 to 0.80), coronary arteriography (adjusted OR 0.85, 95% CI 0.77 to 0.95), other elective catheter-based procedures (adjusted OR 0.87, 95% CI 0.78 to 0.96), and coronary artery bypass surgery (adjusted OR 0.66, 95% CI 0.58 to 0.75) than their white counterparts. Despite these differences in treatment, there were no significant differences in hospital mortality between blacks and whites.

Use of reperfusion therapy for acute myocardial infarction in the United States: data from the National Registry of Myocardial Infarction 2.

BACKGROUND: There is clear evidence that reperfusion therapy improves survival in selected patients with an acute myocardial infarction. However, several studies have suggested that many patients with an acute myocardial infarction do not receive this therapy. Whether this underutilization occurs in patients appropriate for such therapy remains unclear. METHODS AND RESULTS: We examined the use of reperfusion therapy in patients with an acute myocardial infarction hospitalized at 1470 hospitals participating in the National Registry of Myocardial Infarction 2. We identified 84 663 patients who were eligible for reperfusion therapy as defined by diagnostic changes on the initial 12-lead ECG, presentation to the hospital within 6 hours from symptom onset, and no contraindications to thrombolytic therapy. Twenty-four percent of these eligible patients did not receive any form of reperfusion therapy (7.5% of all patients). When multivariate analyses were used, left bundle-branch block (odds ratio [OR]=0.22; 95% CI=0.20 to 0.24), lack of chest pain at presentation (OR=0.22; 95% CI=0.21 to 0.24), age >75 years (OR=0.40, 95% CI=0.36 to 0.43), female sex (OR=0.88, 95% CI=0.83 to 0.92), and various preexisting cardiovascular conditions were independent predictors that the patient would not receive reperfusion therapy. CONCLUSIONS: Reperfusion therapy may be underutilized in the United States. Increased use of reperfusion therapy could potentially reduce the unnecessarily high mortality rates observed in women, the elderly, and other patient groups with the highest risk of death from an acute myocardial infarction.