A two-decades (1975 to 1995) long experience in the incidence, in-hospital and long-term case-fatality rates of acute myocardial infarction: a community-wide perspective.

OBJECTIVES: The purpose of the present study is to describe changes over two decades (1975 to 1995) in the incidence, in-hospital and long-term case-fatality rates associated with acute myocardial infarction (AMI) from a multihospital community-wide perspective. BACKGROUND: Despite the magnitude of, and mortality associated with acute myocardial infarction (AMI), relatively limited population-based data are available to describe recent and temporal trends in the attack and case-fatality rates associated with AMI from a representative population-based perspective. METHODS: The community-based study included 5,270 residents of the Worcester, Massachusetts, metropolitan area hospitalized with confirmed initial AMI in all metropolitan Worcester, Massachusetts, hospitals (1990 census population = 437,000) in 10 one-year periods between 1975 and 1995. RESULTS: The age-adjusted incidence rates of initial AMI increased between 1975 (244 per 100,000) and 1981 (272 per 100,000), after which time these rates declined through 1995 (184 per 100,000). The crude and multivariable-adjusted in-hospital case-fatality rates exhibited a consistent decline between 1975/1978 (17.8%), 1986/1988 (17.0%) and 1993/1995 (11.7%). Although there were no statistically significant differences in the unadjusted long-term case-fatality rates of discharged hospital survivors over the periods under study, declines in the multivariable-adjusted risk of dying within the first year after hospital discharge were observed between the earliest and most recently discharged patients with AMI. CONCLUSIONS: The results of this population-based study of patients with validated initial AMI provide encouragement for efforts directed at the primary and secondary prevention of AMI given declining incidence and case-fatality rates.

Seasonal distribution of acute myocardial infarction in the second National Registry of Myocardial Infarction.

OBJECTIVES: This observational study sought to determine whether cases of acute myocardial infarction (AMI) reported to the second National Registry of Myocardial Infarction (NRMI-2) varied by season. BACKGROUND: The existence of circadian variation in the onset of AMI is well established. Examination of this periodicity has led to new insights into pathophysiologic triggers of atherosclerotic plaque rupture. Although a seasonal pattern for mortality from AMI has been previously noted, it remains unclear whether the occurrence of AMI also displays a seasonal rhythmicity. Documentation of such a pattern may foster investigation of new pathophysiologic determinants of plaque rupture and intracoronary thrombosis. METHODS: We analyzed the number of cases of AMI reported to NRMI-2 by season during the period July 1, 1994 to July 31, 1996. Data were normalized so that seasonal occurrence of AMI was reported according to a standard 90-day length. RESULTS: A total of 259,891 cases of AMI were analyzed during the study period. Approximately 53% more cases were reported in winter than during the summer. The same seasonal pattern (decreasing occurrence of reported cases from winter to fall to spring to summer) was seen in men and women, in different age groups and in 9 of 10 geographic areas. In-hospital case fatality rates for AMI also followed a seasonal pattern, with a peak of 9% in winter. CONCLUSION: The present results suggest that there is a seasonal pattern in the occurrence of AMIs reported to NRMI-2 that is characterized by a marked peak of cases in the winter months and a nadir in the summer months. This pattern was seen in all subgroups analyzed as well as in different geographic areas. These findings suggest that the chronobiology of seasonal variation in AMI may be affected by variables independent of climate.

Twenty-two year (1975 to 1997) trends in the incidence, in-hospital and long-term case fatality rates from initial Q-wave and non-Q-wave myocardial infarction: a multi-hospital, community-wide perspective.

OBJECTIVES: The goal of this study was to examine long-term trends in the incidence, in-hospital and long-term mortality patterns in patients with an initial non-Q-wave myocardial infarction (NQWMI) as compared with those with an initial Q-wave myocardial infarction (QWMI). BACKGROUND: Limited data are available describing trends in the incidence and mortality from an initial QWMI and NQWMI from a multi-hospital community-wide perspective. METHODS: Our study was an observational study of 5,832 metropolitan Worcester, Massachusetts residents (1990 census = 437,000) hospitalized with validated initial acute MI in all greater Worcester hospitals during 11 annual periods between 1975 and 1997. RESULTS: The incidence of QWMI progressively decreased between 1975/78 (incidence rate = 171/100,000 population) and 1997 (101/100,000 population). In contrast, the incidence of NQWMI progressively increased between 1975/78 (62/100,000 population) and 1997 (131/100,000 population). Hospital death rates were 19.5% for patients with QWMI and 12.5% for those with NQWMI. After controlling for various covariates, patients with QWMI remained at significantly increased risk for hospital mortality (adjusted odds ratio = 1.63; 95% confidence interval: 1.35, 1.97). While the hospital mortality of QWMI has progressively declined over time (1975/78 = 24%; 1997 = 14%), the in-hospital mortality for NQWMI has remained the same (1975/78 = 12%; 1997 = 12%). These trends remained after adjusting for potentially confounding prognostic factors. The multivariable adjusted two-year mortality after hospital discharge declined over time for patients with QWMI and NQWMI. CONCLUSIONS: Despite impressive declines in the incidence, in-hospital and long-term mortality associated with QWMI, NQWMI is increasing in frequency and has the same in-hospital mortality now as it did 22 years ago.

Clinical experience with primary percutaneous transluminal coronary angioplasty compared with alteplase (recombinant tissue-type plasminogen activator) in patients with acute myocardial infarction: a report from the Second National Registry of Myocardial Infarction (NRMI-2).

OBJECTIVES: We sought to compare outcomes after primary percutaneous transluminal coronary angioplasty (PTCA) or thrombolytic therapy for acute myocardial infarction (MI). BACKGROUND: Primary PTCA and thrombolytic therapy are alternative means of achieving reperfusion in patients with acute MI. The Second National Registry of Myocardial Infarction (NRMI-2) offers an opportunity to study the clinical experience with these modalities in a large patient group. METHODS: Data from NRMI-2 were reviewed. RESULTS: From June 1, 1994 through October 31, 1995, 4,939 nontransfer patients underwent primary PTCA within 12 h of symptom onset, and 24,705 patients received alteplase (recombinant tissue-type plasminogen activator [rt-PA]). When lytic-ineligible patients and patients presenting in cardiogenic shock were excluded, baseline characteristics were similar. The median time from presentation to initiation of rt-PA in the thrombolytic group was 42 min; the median time to first balloon inflation in the primary PTCA group was 111 min (p < 0.0001). In-hospital mortality was higher in patients in shock after rt-PA than after PTCA (52% vs. 32%, p < 0.0001). In-hospital mortality was the same in lytic-eligible patients not in shock: 5.4% after rt-PA and 5.2% after PTCA. The stroke rate was higher after lytic therapy (1.6% vs. 0.7% after PTCA, p < 0.0001), but the combined end point of death and nonfatal stroke was not significantly different between the two groups (6.2% after rt-PA and 5.6% after PTCA). There was no difference in the rate of reinfarction (2.9% after rt-PA and 2.5% after PTCA). CONCLUSIONS: These findings suggest that in lytic-eligible patients not in shock, PTCA and rt-PA are comparable alternative methods of reperfusion when analyzed in terms of in-hospital mortality, mortality plus nonfatal stroke and reinfarction.

Selective versus routine predischarge coronary arteriography after therapy with recombinant tissue-type plasminogen activator, heparin and aspirin for acute myocardial infarction. TIMI II Investigators.

To ascertain whether predischarge arteriography is beneficial in patients with acute myocardial infarction treated with recombinant tissue-type plasminogen activator (rt-PA), heparin and aspirin, the outcome of 197 patients in the Thrombolysis in Myocardial Infarction (TIMI) IIA study assigned to conservative management and routine predischarge coronary arteriography (routine catheterization group) was compared with the outcome of 1,461 patients from the TIMI IIB study assigned to conservative management without routine coronary arteriography unless ischemia recurred spontaneously or on predischarge exercise testing (selective catheterization group). The two groups were similar with regard to important baseline variables. During the initial hospital stay, coronary arteriography was performed in 93.9% of the routine catheterization group and 34.7% of the selective catheterization group (p less than 0.001), but the frequency of coronary revascularization (angioplasty or coronary artery bypass surgery) was similar in the two groups (24.4% versus 20.7%, p = NS). Coronary arteriograms showed a predominance of zero or one vessel disease (stenosis greater than or equal to 60%) in both groups (routine catheterization group 73.1%, selective catheterization group 61.3%). During the 1st year after infarction, rehospitalization for cardiac reasons and the interim performance of coronary arteriography were more common in the selective catheterization group (37.9% versus 27.6%, p = 0.007 and 28.6% versus 11.6%, p less than 0.001, respectively); however, the interim rates of death, nonfatal reinfarction and performance of coronary revascularization procedures were similar. At the end of 1 year, coronary arteriography had been performed one or more times in 98.9% of the routine catheterization group and 59.4% of the selective catheterization group (p less than 0.001), whereas death and nonfatal reinfarction had occurred in 10.2% versus 7.0% (p = 0.10) and 8.6% versus 9.0% (p = 0.87), respectively. Because the selective coronary arteriography policy exposes about 40% fewer patients to the small but finite risks and inconvenience of the procedure without compromising the 1 year survival or reinfarction rates, it seems to be an appropriate management strategy.

A composite view of cardiac rupture in the United States National Registry of Myocardial Infarction.

OBJECTIVES: This study was done to determine the incidence, timing and prevalence as a cause of death from cardiac rupture in patients with acute myocardial infarction. BACKGROUND: Several clinical trials and overview analyses have suggested that the survival benefit conferred by thrombolytic therapy may be offset by a paradoxic increase in early deaths from cardiac rupture. METHODS: Demographic, procedural and outcome data from patients with acute myocardial infarction were collected at 1,073 United States hospitals collaborating in the United States National Registry of Myocardial Infarction. RESULTS: Among the 350,755 patients enrolled, 122,243 received thrombolytic therapy. In-hospital mortality for the overall patient population, those not treated with thrombolytics (n = 228,512) and those given thrombolytics were 10.4%, 12.9% and 5.9%, respectively (p<0.001). Cardiogenic shock was the most common cause of death in each patient group. Although the incidence of cardiac rupture was low (<1.0%), it was responsible for 7.3%, 6.1% and 12.1%, respectively, of in-hospital deaths (p<0.001). Death from rupture occurred earlier in patients given thrombolytic therapy, with a clustering of events within 24 h of drug administration. Despite the early risk, death rates were comparatively low in thrombolytic-treated patients on each of the first 30 days. By multivariable analysis, thrombolytics, prior myocardial infarction, advancing age, female gender and intravenous beta-blocker use were independently associated with cardiac rupture. CONCLUSIONS: This large registry experience, including over 350,000 patients with myocardial infarction, suggests that thrombolytic therapy accelerates cardiac rupture, typically to within 24 to 48 h of treatment. The possibility that rupture represents an early hemorrhagic complication of thrombolytic therapy should be investigated.

Cardiac rupture associated with thrombolytic therapy: impact of time to treatment in the Late Assessment of Thrombolytic Efficacy (LATE) study.

OBJECTIVES: This prospective ancillary study was conducted to determine the association between the time from symptom onset to treatment and cardiac rupture in patients with acute myocardial infarction. BACKGROUND: There is strong evidence that the time window for thrombolytic therapy should be extended to at least 12 h; however, many clinicians are concerned that late treatment may cause an excessive occurrence of death from cardiac rupture. Because up to 30% of patients with acute myocardial infarction arrive in the hospital > 6 h from symptom onset, resolving this issue is of paramount clinical importance. METHODS: A total of 5,711 patients with acute myocardial infarction were randomized to receive intravenous recombinant tissue-type plasminogen activator (rt-PA) (100 mg over 3 h) or matching placebo, within 6 and 24 h from symptom onset. Both groups received immediate oral aspirin, and a majority of patients received intravenous heparin during the initial 48 h. RESULTS: By 35 days, 177 patients had died, with the cause of death specified as cardiac rupture (53 patients), electromechanical dissociation (42 patients) or asystole (82 patients). An additional 370 patients had died of other causes. In patients treated within 12 h, the proportion of rupture deaths in the group given rt-PA was higher than that observed in those who received placebo, but the difference was not statistically significant. In patients treated after 12 h, there was no evidence of an increased incidence of rupture with rt-PA, and the proportion of deaths due to rupture in this group was lower than that in patients given placebo. However, there was evidence of a difference between rt-PA and placebo with respect to the time that rupture became clinically manifest (treatment by time to death interaction, p = 0.03). CONCLUSIONS: This study provides unequivocal evidence that late treatment (6 to 24 h after symptom onset) with rt-PA is not associated with an increased risk of cardiac rupture. However, for reasons that are unclear, coronary thrombolysis appears to accelerate rupture events, typically to within 24 h of treatment.

Twenty year trends (1975-1995) in the incidence, in-hospital and long-term death rates associated with heart failure complicating acute myocardial infarction: a community-wide perspective.

OBJECTIVES: To describe from a population-based perspective, recent and temporal (1975-1995) trends in the incidence, in-hospital and postdischarge case-fatality rates of heart failure (HF) complicating acute myocardial infarction (AMI). BACKGROUND: Extremely limited data are available describing the incidence and case-fatality rates associated with HF complicating AMI from a community-wide perspective. METHODS: The medical records of 6,798 residents of the Worcester, Massachusetts metropolitan area with validated MI and without previous HF hospitalized in 10 annual periods between 1975 and 1995 were reviewed. RESULTS: The proportion of AMI patients developing HF during hospitalization declined between 1975-1978 (38%) and 1993-1995 (33%) (p < 0.001). After controlling for potentially confounding factors, the risk of developing HF declined progressively, albeit modestly, over time. In-hospital case-fatality rates of patients with AMI complicated by HF declined by approximately 46% between 1975-1978 (33%) and 1993-1995 (18%) (p < 0.001). Improving trends in hospital survival were observed after adjusting for potentially confounding prognostic factors. The one-year post-discharge mortality rate for hospital survivors of HF did not change over the 20-year period under study, even after controlling for additional prognostic characteristics. CONCLUSIONS: The results of this community-wide study suggest encouraging declines in the incidence and hospital death rates associated with HF complicating AMI. Continued efforts need to be directed towards the prevention of HF given the magnitude of this clinical syndrome. Efforts of secondary prevention are needed to identify and improve the treatment of patients with symptomatic left ventricular dysfunction following AMI given the lack of improvement in the long-term prognosis of these patients.

Influence of payor on use of invasive cardiac procedures and patient outcome after myocardial infarction in the United States. Participants in the National Registry of Myocardial Infarction.

OBJECTIVES: We sought to determine the influence of payor status on the use and appropriateness of cardiac procedures. BACKGROUND: The use of invasive procedures affects the cost of cardiovascular care and may be influenced by payor status. METHODS: We compared treatment and outcomes of myocardial infarction among four payor groups: fee for service (FFS), health maintenance organization (HMO), Medicaid and uninsured. Multivariate comparison was performed on the use of invasive cardiac procedures, length of hospital stay and in-hospital mortality in 17,600 patients <65 years old enrolled in the National Registry of Myocardial Infarction from June 1994 to October 1995. To determine the appropriateness of coronary angiography, we compared its use in patients at low and high risk for cardiac events. RESULTS: Angiography was performed in 86% of FFS, 80% of HMO, 61% of Medicaid and 75% of uninsured patients. FFS patients were more likely to undergo angiography than HMO (odds ratio [OR] 1.27, 95% confidence interval [CI] 1.13 to 1.42), Medicaid (OR 2.43, 95% CI 2.11 to 2.81) and uninsured patients (OR 1.99, 95% CI 1.76 to 2.25). Similar patterns for the use of coronary revascularization were found. Among those at low risk, FFS patients were as likely to undergo angiography as HMO patients but more likely than Medicaid and uninsured patients. For those at high risk, FFS patients were more likely to undergo angiography than patients in other payor groups. Adjusted mean length of stay (7.3 days) was similar among all payor groups, but adjusted mortality was higher in the Medicaid group (Medicaid vs. FFS: OR 1.55, 95% CI 1.19 to 2.01). CONCLUSIONS: Payor status is associated with the use and appropriateness of invasive cardiac procedures but not length of hospital stay after myocardial infarction. The higher in-hospital mortality in the Medicaid cohort merits further study.

Early discharge in the thrombolytic era: an analysis of criteria for uncomplicated infarction from the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) trial.

OBJECTIVES: This study sought to readdress the definition of uncomplicated myocardial infarction and to apply clinical criteria for early discharge of such patients in the thrombolytic era. BACKGROUND: Previous studies proposed early hospital discharge at day 7 to 10 after acute myocardial infarction. The potential for earlier discharge of patients with uncomplicated infarction after thrombolysis remains undemonstrated. METHODS: We defined "uncomplicated infarction" a priori as the absence of death, reinfarction, ischemia, stroke, shock, heart failure (Killip class > 1), bypass surgery, balloon pumping, emergency catheterization or cardioversion or defibrillation in the first 4 hospital days. We applied this definition to 41,021 patients in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO-I) trial. We examined death at 30 days and 1 year and rates of in-hospital reinfarction, heart failure, recurrent ischemia, shock and stroke in the uncomplicated and complicated groups created by application of our definition. We also assessed lengths of hospital and cardiac care unit stay. RESULTS: Application of our clinical criteria yielded 23,497 (57.3%) patients in the uncomplicated group at day 4 with a very low risk of death and in-hospital complications: 30-day mortality 1%, reinfarction 1.7%, heart failure 2.6%, recurrent ischemia 6.7%, shock 0.4% and stroke 0.2%. One-year mortality was 3.6%. The median hospital stay was 9 days (7, 12 [25th, 75th percentiles, respectively]), and the median cardiac care unit stay 3 days (3, 5). CONCLUSIONS: Simple clinical characteristics can identify a very low risk post-myocardial infarction population by hospital day 4. Use of these criteria for early discharge planning could substantially reduce length of stay for patients with uncomplicated acute myocardial infarction.

Bilateral brachial artery emboli presenting as aortic dissection.

Loss of peripheral pulses in a patient with chest pain suggests the diagnosis of aortic dissection. An 80-year-old woman presented with an episode of chest pain and acute bilateral loss of upper extremity pulses that was initially treated as aortic dissection. Findings of physical examination and echocardiography were consistent with mitral stenosis. Angiography revealed bilateral brachial artery emboli, which were treated by embolectomy. To our knowledge, this case represents the first report of simultaneous brachial artery emboli in association with mitral stenosis.

Severe metabolic and respiratory alkalosis associated with the treatment of congestive heart failure.

A high blood pH level is usually associated with an extremely poor prognosis. We present a case of significantly elevated arterial blood pH (pH, 7.81) that was associated with the aggressive treatment of congestive heart failure. The recognition of this disorder and the institution of appropriate therapy resulted in complete recovery.

Decade-long trends and factors associated with time to hospital presentation in patients with acute myocardial infarction: the Worcester Heart Attack study.

BACKGROUND: Duration of prehospital delay in patients with acute myocardial infarction (AMI) is receiving increasing attention given the time-dependent benefits associated with prompt use of coronary reperfusion strategies. OBJECTIVE: To examine trends (1986-1997) in time to hospital presentation and factors associated with prolonged delay in a community-wide study of patients with AMI. METHODS: Longitudinal study of 3837 residents of the Worcester, Mass, metropolitan area hospitalized with AMI in 7 one-year periods between 1986 and 1997 in whom information about prehospital delay was available. RESULTS: The mean, median, and distribution of delay times exhibited either inconsistent or no changes over time. In 1986, the mean and median prehospital delay times were 4.1 and 2.2 hours, respectively; these times were 4.3 and 2.0 hours, respectively, in patients hospitalized in 1997. Overall, with no significant differences noted over time, approximately 44% of patients with AMI presented to area-wide hospitals in less than 2 hours after the onset of acute coronary symptoms. Increasing age, history of angina or diabetes, onset of symptoms in the afternoon or evening, and hospitalization in the most recent study year (1997) were significantly associated with delays of more than 2 hours in seeking hospital care after controlling for a variety of factors that might affect delay. CONCLUSIONS: The results of this population-based study suggest that a large proportion of patients with AMI continue to exhibit prolonged delay. The characteristics of many of these individuals can be identified in advance for targeted educational efforts. Arch Intern Med. 2000;160:3217-3223.

Duration of, and temporal trends (1994-1997) in, prehospital delay in patients with acute myocardial infarction: the second National Registry of Myocardial Infarction.

BACKGROUND: Extent of delay in seeking medical care in persons with acute myocardial infarction (AMI) is receiving increasing attention, given the time-dependent benefits associated with early administration of coronary reperfusion therapy. OBJECTIVE: To examine recent data, and temporal trends therein, about duration of prehospital delay in a large (N = 364,131) cross-sectional sample of patients included in the second National Registry of Myocardial Infarction. METHODS: The medical records of patients hospitalized with AMI in 1624 US hospitals from June 1, 1994, to October 31, 1997, were reviewed for information about duration of prehospital delay. RESULTS: There was evidence of a slight decline in average delay times in patients hospitalized in 1997 (5.5 hours) compared with those hospitalized in 1994 (5.7 hours). Median delay times (2.1 hours) did not change. Approximately 20% of patients presented to the hospital within 1 hour of acute symptom onset, and slightly more than two thirds presented within 4 hours. Delay times were more prolonged for older patients, women, nonwhite patients, and patients with a history of diabetes or hypertension vs respective comparison groups. Patients in cardiogenic shock exhibited shorter delay times than less severely ill patients. Patients with previous AMI or who had undergone previous coronary angioplasty presented to the hospital with shorter delay times, as did individuals hospitalized in the Mountain and Pacific regions. CONCLUSIONS: These results provide insights into recent delay times and into groups at risk for prolonged delay.

Recent trends in hospital mortality of acute myocardial infarction--the Worcester Heart Attack Study. Have improvements been realized for all age groups?

BACKGROUND: While age-related differences in patterns of care for acute myocardial infarction have been demonstrated, temporal trends in clinical outcome for patients in different age groups have not been carefully examined. METHODS: We analyzed data collected as part of an ongoing communitywide study of 5480 patients hospitalized with validated acute myocardial infarction in Worcester, Mass, during 7 selected years spanning a 15-year period (1975 through 1990). Patients were stratified into three age groups: less than 65 years (n = 2220), 65 through 74 years (n = 1595), and 75 years or older (n = 1665). Within each age group, the odds of in-hospital death were determined by study year, with adjustments for selected demographic, clinical, and hospital characteristics. RESULTS: For patients less than age 65 years, the odds of dying during the acute hospital phase of myocardial infarction were reduced for all study years relative to the reference year (1975), reaching their lowest level in 1990 (adjusted odds ratio [OR], 0.16; 95% confidence interval [CI], 0.06 to 0.48). For patients aged 65 through 74 years, the odds of dying declined among patients hospitalized in 1978 (adjusted OR, 0.71; 95% CI, 0.39 to 1.29) and 1981 (adjusted OR, 0.36; 95% CI, 0.19 to 0.66) but remained essentially unchanged during the subsequent study years through 1990. For patients 75 years of age or older, the odds of dying declined through 1984 (adjusted OR, 0.42; 95% CI, 0.25 to 0.72) but increased over the following study years: 1986, 1988, and 1990. CONCLUSIONS: While the risk of in-hospital death following acute myocardial infarction has recently declined for patients less than 65 years of age, improvements have not been realized for older age groups. Current patterns of management of acute myocardial infarction in older patients require reexamination.

Accurate patient diagnosis of acute porcine valve failure.

Spontaneous porcine bioprosthetic valve failure is usually of gradual onset. We report a case of acute porcine mitral valve rupture resulting in rapid hemodynamic decompensation. The patient perceived the moment of valvular failure as the abrupt onset of a vibrating sensation in his chest. As the number of patients with porcine bioprostheses continues to increase, acute valvular failure may become a more common clinical entity.

A new wrinkle to the earlobe crease.

Several studies had indicated that the earlobe crease may be a marker of coronary artery disease (CAD). This prospective study of 261 consecutive men undergoing coronary arteriography was carried out to evaluate the association of the earlobe crease with the presence and extent of CAD. A positive earlobe crease was detected in 67% of this population. When examining the presence of CAD in men with (n = 175) and without (n = 86) an earlobe crease, 85% of those with and 85% of those without an earlobe crease showed some degree of CAD. Since the prevalence of an earlobe crease increased with advancing age, we examined the age-specific prevalence rates of CAD in men with and without an earlobe crease and found no significant differences in those rates. A similar lack of association between earlobe crease and CAD was seen when we simultaneously controlled for other potentially confounding factors. We conclude that the reported association between earlobe crease and CAD is due to the fact that the prevalence of earlobe crease and CAD each increase with age.

The increased use of diagnostic procedures in patients with acute myocardial infarction. A community-wide perspective.

As part of a community-wide study examining time trends in the incidence and case-fatality rates of 3263 patients hospitalized with validated acute myocardial infarction (MI) during the years 1975, 1978, 1981, and 1984, we examined changes over time in the use of various noninvasive and invasive diagnostic tests during hospitalization for acute MI. In terms of the noninvasive procedures, exercise testing before hospital discharge increased from only 0.1% of patients in 1975 to 40.3% in 1984, while use of echocardiography (2.5%, 1975; 15.3%, 1984), Holter monitoring (1.0%, 1975; 34.0%, 1984), and radionuclide ventriculography (2.6%, 1975; 52.7%, 1984) also increased dramatically. Concerning the invasive procedures, use of coronary arteriography in patients with acute MI increased from 3.1% in 1975 to 9.8% in 1984. A more striking increase was noted in the use of pulmonary artery catheterization (7.2%, 1975; 19.9%, 1984). Examination of patient characteristics associated with the use of these tests demonstrated that the increased use of these diagnostic procedures was not due to changes in the clinical characteristics of patients hospitalized with acute MI; rather, it was the result of changes in physician practice patterns. If the practice patterns seen in this community-based study are similar to those seen throughout the United States, the charges for these diagnostic tests in 1984 are estimated to approach 600 million dollars. Given current interest in cost-containment and evaluation of clinical practices, these results suggest the need for further observational studies and clinical trials to assess the cost-effectiveness of these diagnostic tests. To assess the cost-effectiveness, it will be necessary to determine if the use of these tests improves the short-term or long-term prognosis of patients hospitalized with acute MI.

Temporal trends (1986-1997) in cholesterol level assessment and management practices in patients with acute myocardial infarction: a population-based perspective.

BACKGROUND: Elevated serum cholesterol levels are associated with increased risk for acute myocardial infarction (AMI) and adverse patient outcomes. It is unclear what proportion of patients have their serum cholesterol levels measured during hospitalization for AMI and are given hypolipidemic therapy. OBJECTIVE: To examine decade-long trends in measurement of serum cholesterol levels during hospitalization for AMI and use of hypolipidemic therapy. METHODS: Observational study of 5204 residents of the Worcester, Mass, metropolitan area hospitalized with validated AMI in all greater Worcester hospitals in seven 1-year periods from 1986 through 1997. RESULTS: Increases in the measurement of serum cholesterol levels during hospitalization for AMI were observed between 1986 and 1991, followed by a progressive decrease; only 24% of patients with AMI in 1997 underwent cholesterol level testing. Younger age, male sex, and absence of a history of cardiovascular disease were associated with an increased likelihood measurement of serum cholesterol levels. Although the relative use of hypolipidemic therapy increased significantly over time (0.4% in 1986 vs 10.7% in 1997), the absolute rate of use remained low. In patients with elevated serum cholesterol levels (>/=6.2 mmol/L [>/=240 mg/dL]), 1.9% received hypolipidemic therapy in 1986 and 36.6% in 1997. CONCLUSIONS: These findings suggest recent declines in the assessment of total cholesterol levels in patients hospitalized with AMI. Although the use of hypolipidemic therapy during hospitalization for AMI has increased over time, considerable room for improvement remains.

Does aspirin consumption affect the presentation or severity of acute myocardial infarction?

BACKGROUND: While consumption of aspirin has been shown to decrease the occurrence of nonfatal cardiac events, the majority of studies have not demonstrated any impact of aspirin intake on cardiovascular mortality. The present population-based study explores the possibility that aspirin consumption affects the presentation and severity of acute myocardial infarction (AMI), and hence the likelihood of clinical detection. METHODS: We monitored the use of aspirin before admission for 2114 patients with a validated diagnosis of AMI in 16 hospitals in the Worcester, Mass, metropolitan area during 1986, 1988, and 1990. The AMIs were characterized as Q wave vs non-Q wave and large (peak creatine kinase levels more than five times normal) vs small (peak creatine kinase levels less than two times normal). RESULTS: A total of 332 patients (16%) with validated AMI took aspirin before hospital admission. Nearly 65% of aspirin users had non-Q wave AMIs, compared with 49% of nonaspirin users. Thirty percent of aspirin users sustained small AMIs, compared with 22% of nonaspirin users. These findings persisted after stratifying for previous AMI, history of coronary disease, receipt of thrombolytic therapy, and exclusion of early hospital deaths. Using multivariable regression models to control for age, gender, previous evidence of coronary disease, and use of other medications, prior aspirin consumption remained independently associated with AMI type (non-Q-wave AMI) and smaller infarct size. CONCLUSION: Aspirin consumption appears to modify the presentation of AMI, increasing the likelihood that the infarct will be of the small, non-Q-wave variety.