Do patients in whom myocardial infarction has been ruled out have a better prognosis after hospitalization than those surviving infarction?

Sudden Death Caused by Gastroesophageal Varices Rupture: Insights From an Autopsy-Based Case Series Unraveling the Pathological Events

Sudden death is characterized by natural yet unexpected death, typically occurring within 24 hours from the onset of the patient's symptoms. While the majority of sudden deaths stem from cardiac issues/causes, there are instances where non-cardiac factors are at play. One such scenario involves hemorrhage from ruptured esophageal varices, a complication that stems from portal hypertension. Portal hypertension can manifest due to a range of pre-hepatic, hepatic, and post-hepatic conditions, with liver cirrhosis being the primary culprit. Although sudden death cases linked to the gastrointestinal system are relatively rare, the rupture of gastroesophageal varices, precipitating severe morbidity and a high mortality rate, represents a life-threatening condition. In this context, we present a case series encompassing five instances of sudden natural deaths arising from the rupture of gastroesophageal varices.

The significance of ST and T changes for the development of coronary events in patients with acute coronary chest pain, treated in a coronary care unit without verified acute myocardial infarction

The one-year prognosis for patients with a confirmed diagnosis of acute myocardial infarction (AMI) was compared with that of non-AMI patients treated in the coronary care unit (CCU). The one-year incidence of coronary events (CE) after discharge from CCU was 37% in the 51 AMI patients and 20% in the 81 non-AMI patients. The one-year mortality rates were 27 and 4%, respectively. Among the non-AMI patients, well known risk factors such as hypertension, previous AMI, congestive heart failure, smoking, diabetes and hyperlipaemia were not more common in those who developed a CE. ST segment depression and T wave inversion, each of at least 0.1 mV, in three or more ECG leads were selective criteria for a high-risk group with respect to CE. Preventive measures should be considered in this group of patients without verified AMI.

Myoglobin and creatine kinase release in coronary care patients without acute myocardial infarction

Fifty-nine consecutive coronary care patients, clinically evaluated as not having acute myocardial infarction (AMI) and with a duration of symptoms of less than 6 hours on admission, were studied. Serum myoglobin (MG) and creatine kinase (CK) were determined sequentially during the first 25 hours. Two groups are identified, one with a pattern of a serum MG peak followed by a CK peak and one without. Twenty-four patients had a serum MG peak of 137 plus or minus 33 micrograms x 1(-1) followed by a CK peak of 1.6 plus or minus 0.9 microkat x 1(-1). Values above th reference limits were found in 19 patients for MG and in 5 for CK. After the onset of symptoms, the peaks were observed at 5.3 plus or minus 2.8 (MG) and 12.7 plus or minus 5.3 (CK) hours. Compared to the group without MG and CK peaks, ECG alterations were more frequent in the group with peaks, 20/24 (84%) versus 15/35 (43%). The entire patient group had the same 2-year incidence of major coronary events as patients with AMI, but it tended to be higher in patients with MG/CK release.

The prognosis for patients referred with suspected acute myocardial infarction

A follow-up investigation of the prognosis of 381 patients admitted with suspected acute myocardial infarction (AMI) has been carried out in respect of later AMI or death. During hospitalization the patients were divided into groups with particular attention to patients with no demonstrable myocardial infarction but with ischaemic heart disease (non-AMI) and patients with confirmed AMI. All patients were subjected to follow-up for 43 months (range 37-54). The mortality from cardiovascular causes after four years was 26.2% of 130 non-AMI patients and 25.8% of AMI patients. The majority of new infarctions were found in the AMI patients, but with even increase in both groups, 50% occurring within the first 12 months. The groups were studied with regard to earlier manifestations of ischaemic heart disease and heart failure during hospitalization, without any difference being observed. Due to the poor prognosis the question is raised whether non-AMI patients as a group should be offered prophylactic therapy.

The prognosis for patients admitted to a coronary care unit due to suspected acute myocardial infarction with and without confirmed diagnosis

In a retrospective study the incidence of AMI and death after discharge from CCU have been recorded in 67 patients with and 93 without a diagnosis of AMI confirmed in the CCU. No statistically significant differences were found between the two groups in mortality rate during the first 3 years, 18.3% (non-AMI) and 22.4% (AMI), or in cardiac events, sudden death and AMI, 19.3% (non-AMI) and 24.9% (AMI), during the first 2 years after discharge. Non-AMI patients with either previous AMI, angina pectoris or ST-T abnormalities in the ECG accounted for the major part of cardiac events in this group. The mortality rates in the two groups, compared to a normal population matched for sex and age, were in the AMI group in the 1st year 13.4 and 2.6% (p less than 0.01), in the 2nd year 3.4 and 2.8% (p greater than 0.05), in the 3rd year 7.1 and 2.9% (p greater than 0.05) and in the non-AMI group in the 1st year 11.8 and 1.8% (p less than 0.01), in the 2nd year 3.7 and 2.0% (p greater than 0.05), in the 3rd year 3.8 and 2.1% (p greater than 0.05). It is concluded that the prognosis after discharge from the CCU is as unfavourable for patients without as for patients with AMI. The mortality is highest during the first 6-12 months after discharge.

Serum cardiac markers in patients with acute myocardial infarction: oxidative stress, C-reactive protein and N-terminal probrain natriuretic Peptide

The aim of this study was to investigate the predictive value of an oxidative stress, C-reactive protein (CRP) and N-terminal probrain natriuretic peptide (NT-proBNP) biomarkers in acute myocardial infarction (AMI). The study population contained 100 patients with AMI and 40 healthy subjects. Malondialdehyde (MDA) was measured as thiobarbituric acid reactive substances. Total antioxidant status (TAC) was assayed with colorimetric method. CRP and NT-proBNP was quantitated by immunoassay. MDA, CRP and NT-proBNP levels were found significantly high in patients with AMI as compared to healthy controls (p<0.01). Patients were divided into six groups based on the presence of disease history before AMI. In patients with non-disease before AMI. MDA, CRP and NT-proBNP levels were lowest among the patient groups. MDA levels in patients with hyperlipidemia/ diabetes/renal disease were higher than the other groups. TAC levels in patients with hypertension were lower than as compared to healthy controls (p<0.05). CRP levels in hypertension + hyperlipidemia patients and NT-proBNP levels in cardiovascular + hypertension patients were found high as compared to other patient groups. It is concluded that serum levels of MDA, CRP and NT-proBNP were significantly increased in patients with AMI and these markers were strongly predictive in AMI.

The exciting story of cardiac biomarkers: from retrospective detection to gold diagnostic standard for acute myocardial infarction and more

This paper reviews the history of the contribution of the laboratory medicine to clinical cardiology and discusses the most important steps in this field. Until 20 years ago, the clinical laboratory only placed at the cardiologist's disposal a few assays for the retrospective detection of cardiac tissue necrosis, such as enzymatic methods for creatine kinase and lactate dehydrogenase activities. However, in the latter part of the 20th century, highly sensitive and specific assays, such as cardiac troponins, as well as assays for markers of myocardial function, such as cardiac natriuretic peptides, rapidly changed the scenario of clinical management of patients with cardiac diseases, assigning to the laboratory a pivotal role in the overall diagnostic flow. This is witnessed by the recent incorporation of these markers into international guidelines and in the redefinition of myocardial infarction. For the foreseeable future, new serum markers of myocardial ischemic, i.e. reversible, injury or related to coronary plaque instability and disruption are expected.

Exercise testing in chest pain units: rationale, implementation, and results

Chest pain units are now established centers for assessment of low-risk patients presenting to the emergency department with symptoms suggestive of acute coronary syndrome. Accelerated diagnostic protocols, of which treadmill testing is a key component, have been developed within these units for efficient evaluation of these patients. Studies of the last decade have established the utility of early exercise testing,which has been safe, accurate, and cost-effective in this setting. Specific diagnostic protocols vary, but most require 6 to 12 hours of observation by serial electrocardiography and cardiac injury markers to exclude infarction and high-risk unstable angina before proceeding to exercise testing. However, in the chest pain unit at UC Davis Medical Center,the approach includes "immediate" treadmill testing without a traditional process to rule out myocardial infarction. Extensive experience has validated this approach in a large, heterogeneous population. The optimal strategy for evaluating low-risk patients presenting to the emergency department with chest pain will continue to evolve based on current research and the development of new methods.

Cardiac Biomarkers for Detection of Myocardial Infarction: Perspectives from Past to Present

Editor’s Note: With great pleasure and anticipation in recognition of Clinical Chemistry’s 50th anniversary, I have been able to arm-twist four talented scientists to document their impressive marks on the science of diagnostics in the field of cardiac biomarkers and detection of myocardial infarction. Their exciting discoveries and applications have dramatically influenced the fields of laboratory medicine and cardiology and have greatly influenced the care and management of thousands of patients suffering from coronary artery disease leading to acute myocardial infarction. As a matter of historical record, I owe a great deal of thanks to each one of the coauthors of this special report because each one has personally influenced my scientific career. I met Dr. Rosalki, during my postdoctoral training, at a national AACC meeting, where he kindly answered my numerous queries regarding creatine kinase enzymology and muscle physiology. Dr. Roberts, while serving as Director of the Coronary Care Unit at Washington University in St. Louis, generously allowed this fledgling fellow into his laboratory and shared many of his clinical and experimental findings with me. Dr. Katus, whom I first met at a scientific meeting sponsored by Boehringer Mannheim in 1986 in Bavaria, where I first became fascinated with cardiac troponin T, has remained a friend and colleague. Lastly, Dr. Ladenson, who as mentor, scientific colleague, and close friend remains ultimately responsible for both my professional growth as a clinical chemist (he was my postdoctoral fellowship advisor) and for stimulating and encouraging my goals and aspirations in the field of cardiac biomarkers. With the descriptions of the ground-breaking science described below, I am extremely excited and optimistic that the future of cardiac biomarkers is secure and open to new discoveries by the Rosalkis, Robertses, Katuses, and Ladensons of the future.

—Fred Apple

Anginal symptoms consistently predict total mortality among outpatients with coronary artery disease

BACKGROUND

Age, race, education, and diabetes have been associated with differences in anginal symptoms, treatments, and outcomes among outpatients with coronary artery disease (CAD), but there is little data on whether such characteristics affect relationships between anginal symptoms and mortality.

METHODS

Using a prospective cohort design, we examined associations of anginal symptoms, as assessed by the Seattle Angina Questionnaire, with total mortality among 8908 outpatients with CAD to investigate whether this relationship is influenced by patient demographic or clinical characteristics. Potential effect modification was primarily assessed for age, race, education, and diabetes, and secondarily assessed for smoking, prevalent congestive heart failure (CHF), myocardial infarction, and coronary revascularization.

RESULTS

Over 2 years mean follow-up, there were 896 deaths. After adjustment for potential confounders, persons reporting greater physical limitation due to angina had higher mortality: 27% higher with mild limitation (hazard ratio [HR] 1.27, 95% CI 0.98-1.64), 61% higher with moderate limitation (HR 1.61, 95% CI 1.27-2.05), and 2.5-fold higher with the greatest limitation (HR 2.55, 95% CI 1.97-3.30), compared with little or no limitation (P for trend <.001). Anginal instability was also independently predictive of mortality. There was little evidence that these relationships varied by age, race, education, diabetes, smoking, or presence of CHF, prior myocardial infarction, or prior coronary revascularization (P for each interaction >.28). Anginal symptoms predicted higher mortality risk comparable to a decade of age difference, presence of diabetes, or presence of CHF.

CONCLUSIONS

Among outpatients with CAD, self-reported anginal symptoms consistently predict mortality irrespective of differences in age, race, education, or clinical comorbidities.

Ten-year mortality for patients discharged after hospitalization for chest pain or other symptoms raising suspicion of acute myocardial infarction in relation to hospital discharge diagnosis

AIM

To describe the 10-year prognosis for patients discharged after hospitalization for chest pain or other symptoms giving an initial suspicion of acute myocardial infarction (AMI) in relation to the final hospital diagnosis and furthermore to compare the outcome amongst these patients with the outcome amongst a sex-, age- and community-matched control population.

METHODS

All patients who were hospitalized because of chest pain or other symptoms raising a suspicion of AMI and who were discharged alive from hospital. Patients were divided into three groups according to the final diagnosis: (1) confirmed or possible AMI, (2) confirmed or possible myocardial ischaemia and (3) other aetiology. Information on 10-year mortality was available in 3103 patients. A sex-, age- and community-matched control population (n=3221) was compared with the study population in terms of 10-year mortality. TIME OF SURVEY: 15 February 1986 to 9 November 1987.

SETTING

Sahlgrenska University Hospital.

RESULTS

Patients with confirmed or possible AMI (n=849) had a significantly higher mortality (59.4%) than patients with confirmed or possible myocardial ischaemia (n=1191) who had a mortality of 49.5% (P < 0.0001). The latter group had a higher mortality than patients with 'other aetiology' (n=1063) of whom 40.6% died (P < 0.0001). When comparing the prognosis for patients with AMI and myocardial ischaemia, there was a significant interaction with sex, with a more marked difference in women than in men. Amongst all patients, the 10-year mortality was 49.1 vs. 37.3% in the control group (P < 0.0001).

CONCLUSION

The very long term prognosis was strongly associated with diagnosis amongst patients hospitalized and discharged alive because of chest pain or other symptoms raising suspicion of AMI. The absolute mortality difference between patients who were discharged from hospital with confirmed diagnosis of AMI and those whose symptoms were considered to have other aetiology than AMI or ischaemia was nearly 20%. However, the absolute mortality difference between the patients included in the survey and a control population was only 12%.

Acute ischemic syndromes. Chest pain center concept

CPCs have been developed to meet the clinical challenge posed by the diverse group of patients presenting to the ED with findings suggestive of a coronary event. Using a protocol-driven approach, high- and low-risk patients can be identified on presentation, facilitating urgent therapy in the former and triage of the latter to more deliberate management. Most CPCs focus on low-risk patients who are being increasingly managed by accelerated diagnostic protocols. These methods comprise systematic strategies that include innovative diagnostic approaches during a 6 to 12 hour period of observation with serial ECGs, continuous monitoring and cardiac biomarker measurements. A negative evaluation is usually followed by predischarge stress testing, and positive findings mandate admission. An essential aspect of the CPC strategy is continuity of care for patients with negative cardiac evaluations. Current data indicate that management of low-risk patients with chest pain in a CPC is safe accurate, and appears to be cost-effective.

Comparison of troponin T versus creatine kinase-MB in suspected acute coronary syndromes

Limitations of creatine kinase-MB (CK-MB) have led to alternative biochemical markers, including troponin T (TnT), to detect myocardial necrosis. Limited data are available regarding the predictive value of this new marker in patients with chest pain of uncertain etiology. Therefore, we prospectively compared CK-MB and TnT in a broad population with suspected acute coronary syndromes, including those admitted to a short-stay chest pain unit. CK-MB, quantitative TnT levels, and a rapid bedside assay were performed at 0, 4, 8, and 16 hours. Adverse events, including infarction, recurrent ischemia, coronary surgery, need for catheterization and/or intervention, stroke, congestive heart failure, or death, were identified by chart review and by follow-up phone call at 6 months. Of 707 patients, 104 were excluded for creatinine >2 mg/dl or incomplete data, leaving a total cohort of 603 patients. Coronary Care Unit admissions were 18%, intermediate care admissions were 14%, telemetry admissions is 21%, and admissions to 24-hour short-stay area were 47%. TnT (at 0.1 ng/ml) and CK-MB were positive in a similar proportion of patients (20.4% and 19.7%, respectively); however, the patients identified by TnT and CK-MB were not identical. In-hospital adverse events occurred in 37.1% with no differences in positive predictive value for the markers (p = NS). If CK-MB and TnT were negative, the early adverse event rate was 27%. No cardiac marker was positive by 16 hours in 54.9% of patients with an adverse event. Six-month follow-up was obtained in 576 of the 603 patients (95.5%). One hundred fifty-five late adverse events occurred in 134 patients (23.3%) at an average of 3.3+/-2.5 months after discharge. If both markers were negative, the late event rate was 20.2% and did not increase in patients with positive CK-MB or TnT >0.2 ng/ml. However, the late event rate was substantially higher (52.9%) in those with intermediate TnT levels of 0.1 to 0.2 ng/ml (p = 0.002). Thus, TnT is a suitable alternative to CK-MB in patients with suspected acute coronary syndromes. The rapid bedside assay is comparable to quantitative TnT and may enable early diagnosis and triage. A negative cardiac marker value (TnT or CK-MB) does not necessarily confer a low risk of complication in patients presenting with acute chest pain to an emergency department.

Predictors of death during 5 years after hospital discharge among patients with a suspected acute coronary syndrome with particular emphasis on whether an infarction was developed

AIM

To describe predictors of death after hospital discharge during 5 years of follow-up in a consecutive series of patients surviving hospitalization for symptoms and signs of a confirmed or suspected acute coronary syndrome.

PATIENTS AND METHODS

All patients who between February 15, 1986 and November 9, 1987, were hospitalized at Sahlgrenska University Hospital in Göteborg, Sweden, and fulfilled the above given criteria.

RESULTS

In all, 1948 patients were included of whom 731 (38%) had a confirmed acute myocardial infarction (AMI). Independent risk indicators for death were: age (P=0.0001); male sex (P=0.005); a history of previous AMI (P=0.0001), diabetes mellitus (P=0.003) and smoking (P=0.0001); development of AMI during first 3 days in hospital (P=0.0001); in-hospital signs of congestive heart failure (P=0.0001); prescription of digitalis (P=0.001) and diuretics (P=0.02) at hospital discharge. A history of smoking interacted significantly (P=0.02) with the relationship between development of AMI and prognosis. Thus, the difference between patients who did and who did not develop an AMI was more pronounced among non-smokers than smokers. Other factors which interacted significantly with this relationship were a history of angina pectoris, and development of ventricular fibrillation and hypotension while in hospital.

CONCLUSION

Among hospital survivors of a confirmed or suspected acute coronary syndrome predictors of death during 5 years were: age, male sex, history of AMI, diabetes mellitus and smoking, development of AMI and congestive heart failure while in hospital and prescription of digitalis and diuretics at hospital discharge. A history of smoking and angina pectoris as well as development of hypotension and ventricular fibrillation while in hospital interacted significantly with the relationship between development of AMI and prognosis.

Evaluation and risk stratification of patients with chest pain in the emergency department. Predictors of life-threatening events

While assessing chest pain in the emergency department, physicians must first estimate the probability of acute ischemic states in the patient. This first estimate is based on the patient's history, physical examination, and electrocardiogram. Patients who meet the threshold for acute cardiac ischemia are further evaluated to confirm or exclude this diagnosis, while other life-threatening factors are excluded.

Evaluation of chest pain in the emergency department

The evaluation of chest pain in the emergency setting should be systematic, risk based, and goal driven. An effective program must be able to evaluate all patients with equal thoroughness under the assumption that any patient with chest pain could potentially be having an MI. The initial evaluation is based on the history, a focused physical examination, and the ECG. This information is sufficient to categorize patients into groups at high, moderate, and low risk. Table 14 is a template for a comprehensive chest-pain evaluation program. Patients at high risk need rapid initiation of appropriate therapy: thrombolytics or primary angioplasty for the patients with MIs or aspirin/heparin for the patients with unstable angina. Patients at moderate risk need to have an acute coronary syndrome ruled in or out expediently and additional comorbidities addressed before discharge. Patients at low risk also need to be evaluated, and once the likelihood of an unstable acute coronary syndrome is eliminated, they can be discharged with further evaluation performed as outpatients. Subsequent evaluation should attempt to assign a definitive diagnosis while also addressing issues specific to risk reduction, such as cholesterol lowering and smoking cessation. It is well documented that 4% to 5% of patients with MIs are inadvertently missed during the initial evaluation. This number is surprisingly consistent among many studies using various protocols and suggests that an initial evaluation limited to the history, physical examination, and ECG will fail to identify the small number of these patients who otherwise appear at low risk. The solution is to improve the sensitivity of the evaluation process to identify these patients. It appears that more than simple observation is required, and at the present time, no simple laboratory test can meet this need. However, success has been reported with a number of strategies including emergency imaging with either radionuclides such as sestamibi or echocardiography. Early provocative testing, either stress or pharmaceutic, may also be effective. The added value of these tests is only in their use as part of a systematic protocol for the evaluation of all patients with acute chest pain. The initial evaluation of the patient with chest pain should always consider cardiac ischemia as the cause, even in those with more atypical symptoms in whom a cardiac origin is considered less likely. The explicit goals for the evaluation of acute chest pain should be to reduce the time to treat MIs and to reduce the inadvertent discharge of patients with occult acute coronary syndromes. All physicians should become familiar with appropriate risk stratification of patients with acute chest pain. Systematic strategies must be in place to assure rapid and consistent identification of all patients and the expedient initiation of treatment for those patients with acute coronary syndromes. These strategies should include additional methods of identifying acute coronary syndromes in patients initially appearing as at moderate or low risk to assure that no unstable patients are discharged. All patients should be followed up closely until the cardiovascular evaluation is completed and, when possible, a definitive diagnosis is determined. Finally, this must be done efficiently, cost-effectively, and in a manner that will result in an overall improvement in patient care.

Improved troponin T ELISA specific for cardiac troponin T isoform: assay development and analytical and clinical validation

The first generation of troponin T ELISA (TnT 1) can yield false-positive results in patients with severe skeletal muscle injury. Therefore, a cardiac-specific second-generation troponin T ELISA (TnT 2) was developed, in which the cross-reactive antibody 1B10 has been replaced by a high-affinity cardiac-specific antibody M11.7. No cross-reactivity of TnT 2 was observed with purified skeletal muscle troponin T (1000 μg/L) or in test samples from 43 marathon runners and 24 patients with rhabdomyolysis and highly increased creatine kinase. TnT 2 was increased &gt;0.2 μg/L in 5 of 40 patients with renal failure and in 4 of 20 muscular dystrophy patients. The detection limit is 0.012 μg/L. Day-to-day imprecision (CV) within the range 0.19–14.89 μg/L was &lt;5.8%. In 4955 patients without myocardial damage, 99.6% had TnT &lt;0.10 μg/L. Assay comparison (TnT 1 vs TnT 2) over the whole concentration range (i.e., in 323 samples from AMI-suspected patients) showed a slope, intercept, and standard error of estimate (Sey) of 1.18, 0.01 μg/L, and 0.81 μg/L, respectively.

Improvement of ED prediction of cardiac mortality among patients with symptoms suggestive of acute myocardial infarction

A study was undertaken to evaluate the 1-year risk of cardiac death for patients with chest pain/suspected acute myocardial infarction in the emergency department (ED) and express the prognosis in a statistical model. Clinical variables and electrocardiogram were correlated to cardiac death during 1 year. Cox regression model was used to estimate the risk of death as a continuous function of a risk score and the time interval. From these, the prognosis for each patient can be calculated. There were 6,794 visits by 5,303 patients followed for 1 year, during which 604 patients died. The absolute risk of cardiac death can be calculated from the independent predictors for cardiac death: age; sex; histories of diabetes mellitus, hypertension, and congestive heart failure; and symptoms, electrocardiographic pattern, and degree of suspicion of acute myocardial infarction on admission. This model allows estimation of the prognosis for every patient with chest pain/suspected acute myocardial infarction from data easily available in the ED.

Comprehensive strategy for the evaluation and triage of the chest pain patient

STUDY OBJECTIVE

To evaluate the safety and efficacy of a systematic evaluation and triage strategy including immediate resting myocardial perfusion imaging in patients presenting to the emergency department with chest pain of possible ischemic origin.

METHODS

We conducted an observational study of 1,187 consecutive patients seen in the ED of an urban tertiary care hospital with the chief complaint of chest pain. Within 60 minutes of presentation, each patient was assigned to one of five levels on the basis of his or her risk of myocardial infarction (MI) or unstable angina (UA): level 1, MI; level 2, MI/UA; level 3, probable UA; level 4, possible UA; and level 5, noncardiac chest pain. In the lower risk levels (3 and 4), immediate resting myocardial perfusion imaging was used as a risk-stratification tool alone (level 4) or in combination with serial markers (level 3).

RESULTS

Acute MI, early revascularization indicative of acute coronary syndrome, or both were consistent with risk designations: level 1: 96% MI, 56% revascularization; level 2: 13% MI, 29% revascularization; level 3: 3% MI, 17% revascularization; level 4: .7% MI; 2.5% revascularization. Sensitivity of immediate resting myocardial perfusion imaging for MI was 100% (95% confidence interval [CI], 64% to 100%) and specificity 78% (74% to 82%). In patients with abnormal imaging findings, risk for MI (7% versus 0%, P < .001; relative risk [RR], 50; 95% CI, 2.8 to 889) and for MI or revascularization (32% vs 2%, P < .001; RR, 15.5; 95% CI, 6.4 to 36) were significantly higher than in patients with normal imaging findings. During 1-year follow-up, patients with normal imaging findings (n = 338) had an event rate of 3% (revascularization) with no MI or death (combined events: negative predictive value, 97%; 95% CI, 95% to 98%). Patients with abnormal imaging findings (n = 100) had a 42% event rate (combined events: RR, 14.2; 95% CI, 6.5 to 30; P < .001), with 11% experiencing MI and 8% cardiac death.

CONCLUSION

This strategy is a safe, effective method for rapid triage of chest pain patients. Rapid perfusion imaging plays a key role in the risk stratification of low-risk patients, allowing discrimination of unsuspected high risk patients who require prompt admission and possible intervention from those who are truly at low risk.

The prognostic impact of prior low grade histology in patients with anaplastic gliomas: a case-control study

At the time of recurrence, the majority of low-grade cerebral gliomas transform to a higher grade of histologic malignancy. The purpose of this study was to determine the survival outcome for patients whose anaplastic gliomas began as low-grade tumors compared with patients with de novo high-grade gliomas. Seventy-seven (11.5%) of 667 patients with anaplastic gliomas consecutively treated at the University of Alabama at Birmingham had histologically proven prior low-grade tumors. As a group, the patients with prior low-grade tumors would be expected to have a relatively favorable outcome, as they were younger and had a lower proportion of glioblastoma multiforme than the patients with de novo anaplastic gliomas. The provide a valid comparison, we performed a matched case-control study. We matched 68 patients from the prior low-grade group one-to-one with patients from de novo group for tumor histology, age, Karnofsky performance scores, and type of surgery, without knowledge of outcome. The two groups received comparable radiotherapy and chemotherapy. For the 68 patients with prior low-grade tumor, median actuarial survival from the time of diagnosis of malignant degeneration was 19.7 months and the 5-year survival rate was 22%, compared with 22.0 months and 28% for the 68 matched de novo patients. Kaplan-Meier survival curves for the two group did not significantly differ (p = 0.24 by logrank test). There were no significant survival differences between the patient subsets of prior low-grade versus de novo with glioblastoma, anaplastic astrocytoma, or anaplastic oligodendroglioma/mixed anaplastic glioma. The data indicate that the currently available treatment options, the survival outlook for patients with anaplastic gliomas, whose tumors arose from transformation of low-grade gliomas, is equivalent to the prognosis for patients with de novo anaplastic gliomas.

Patterns of practice in emergency department management of chest pain of suspected cardiac origin: clinical utility of single stat creatine kinase (CK)

The patterns of practice and the clinical utility of a single stat creatine kinase (CK) level in the emergency department management of chest pain of suspected cardiac origin were examined by a prospective observational study using a two-part questionnaire, completed by physicians before and after availability of CK results. The results showed that of the 776 patients in the study, 135 were admitted to hospital with acute myocardial infarction (AMI), 285 were admitted for reasons other than AMI, 343 were discharged, and 13 died or were transferred to another hospital. Although initial and final diagnoses in the emergency department did not differ in 597 patients (77%), initial decisions to admit or discharge were made in only 244 (31%) patients without waiting for CK results, and in 401 (52%) cases, decisions on patient disposition were deferred. Of 218 patients who had elevated CK levels, 193 (89%) were admitted, 121 for AMI. Only five (< 1%) patients who would otherwise have been discharged were admitted because of elevated CK levels. Of the 343 discharges, 245 (71%) occurred after the physicians knew the CK results. It is concluded that emergency department physicians routinely make changes in their diagnostic and management decisions based on current information and as it becomes updated. This study also suggests that there appears to be a heavy reliance on a single CK assay, although the relative importance of this diagnostic test compared to other factors is not known. Further studies are necessary.

Risk indicators for death and prognosis among patients in whom acute myocardial infarction was not confirmed in relation to prescription of beta blockers at discharge

A large number of studies have shown the prognosis after acute myocardial infarction (AMI) to be favorably affected by treatment with beta blockers. Whether such treatment also will have a favorable effect on the prognosis in patients in whom AMI was not confirmed has not been shown. A study was undertaken at Sahlgren's Hospital, Göteborg, to determine risk indicators for death and prognosis among 1,443 patients in whom AMI was not confirmed and who survived hospitalization in relation to whether or not beta blockers were prescribed at discharge. One-year mortality was determined and p values were corrected for differences at baseline. Of the 1,443 patients who participated in the analyses, 44% were prescribed beta blockers. They differed from the remaining patients by younger age, predominance of men, a more frequent history of AMI, angina pectoris, and hypertension, and a less frequent history of congestive heart failure. Patients in whom beta blockers were prescribed had a 1-year mortality of 6% compared with 16% in those not on beta blockers (p < 0.001). The difference was similar in various subgroups according to clinical history.

Prognosis, severity of symptoms, and aspects of well-being among patients in whom myocardial infarction was ruled out

In a high proportion of patients hospitalized due to suspected acute myocardial infarction (AMI) the diagnosis cannot be confirmed. The majority of these patients have ischemic heart disease and are at risk for subsequent cardiac events. The aim of this study was to describe the severity of symptoms and various aspects of well-being 1 year after hospitalization due to suspected AMI in surviving patients in whom the diagnosis was not confirmed, and to relate the observations to those found among survivors of a confirmed AMI. All patients admitted to Sahlgrenska Hospital, Göteborg, due to suspected AMI and who were alive after 1 year were asked to answer a questionnaire including questions regarding cardiovascular, psychiatric, and psychological symptoms. Patients in whom AMI was not confirmed reported more cardiovascular symptoms, for example, chest pain (p < 0.001), dyspnea (p < 0.01), palpitations (p < 0.001), and fatigue (p < 0.01) when compared with patients who suffered confirmed AMI. The majority of psychosomatic and psychological parameters evaluated were also more frequently reported by these patients and their quality of life seems to be worse compared with survivors of AMI.

Ten-year mortality rate among patients in whom acute myocardial infarction was not confirmed in relation to clinical history and observations during hospital stay: experiences from the Göteborg Metoprolol Trial

BACKGROUND

The majority of patients hospitalized due to suspected acute myocardial infarction (AMI) will eventually not develop infarction. Information about the long-term prognosis in this patient population is limited.

AIM

To describe the mortality during 10 years of follow-up in patients hospitalized due to an initially strong suspicion of AMI, but in whom the diagnosis of AMI could not be confirmed.

PATIENTS

All patients participating in an early intervention trial with metoprolol in suspected AMI, but in whom the diagnosis was not confirmed. Patients were included during 1976-1981.

RESULTS

In all 1395 patients were included in the study, of whom 586 did not fulfil the criteria for confirmed AMI. The overall mortality during 10 years of follow-up in this population was 26%. In a multivariate analysis considering age, sex, history of cardiovascular diseases, initial heart rate and various complications during the hospital stay, including congestive heart failure, severe ventricular arrhythmias, tachycardia, hypotension, high degree AV-block and severe chest pain, the following appeared as independent predictors of death: previous infarction (P < 0.001), age (P < 0.001), history of diabetes mellitus (P < 0.001) history of smoking (P < 0.05), history of hypertension (P < 0.05), male sex (P < 0.05), and the initial heart rate (P < 0.05).

CONCLUSION

Among patients in whom AMI was not confirmed the major risk indicators for death during 10 years of follow-up were: a history of cardiovascular diseases and smoking, age, male sex and high heart rate on admission to hospital.

Unstable angina: prognosis, noninvasive risk assessment, and strategies for management

Risk stratification in patients with unstable angina is a major clinical problem with important therapeutic implications. Antiplatelet therapy is clearly effective in reducing the occurrence of myocardial infarction and death in this syndrome. Interventions including coronary bypass surgery and coronary angioplasty are frequently recommended for these patients, but the most appropriate application of these techniques needs to be further defined. After a brief discussion of the value of medical and interventional therapies, this review focuses on the clinical and noninvasive predictors of adverse events in unstable angina. An overall management strategy for these patients, based on current information, will be proposed.

Prognosis in diabetics in whom the initial suspicion of acute myocardial infarction was not confirmed

For 2,058 consecutive patients hospitalized for suspected acute myocardial infarction (AMI) but in whom AMI was later ruled out, we describe the prognosis with particular emphasis on diabetics. In all, a previous history of diabetes mellitus occurred in 290 (14%) of the patients. Compared with nondiabetics, they had a longer delay time between onset of symptoms and arrival in hospital. During 1 year of follow-up, their mortality rate was 28% compared with 14% for nondiabetics (p < 0.001), and their reinfarction rate was 20% compared with 10% for nondiabetics. More diabetics died in association with a fatal myocardial infarction and more frequently had ventricular fibrillation preceding death. With the exception of reinfarction, no clear difference in terms of morbidity was observed between the two groups. We conclude that the prognosis in diabetics in whom AMI is ruled out is poor, with between one-quarter and one-third not surviving 1 year.

The diagnosis of acute myocardial infarction in the emergency department; Part 2

At present, routine use of cardiac enzymes in the emergency department (ED) cannot be justified, except possibly as a final screen prior to discharge. Computer-derived predictive instruments do not surpass the physician's diagnostic sensitivity for acute myocardial infarction (AMI), but do demonstrate significantly higher specificity. Limited data exist on the utility of echocardiography and thallium scanning in the ED. Methods of triaging patients on the basis of prognosis are well supported in the literature. The physician's high diagnostic sensitivity is maintained at the cost of significant numbers of admissions who subsequently rule out for AMI. No single clinical variable or combination of clinical variables can reliably confirm or exclude AMI in the ED. Ultimately, the physician's clinical assessment must remain the final determinant of the necessity for admission. However, judicious use of prediction rules and prognostic indicators should improve resource utilization.

Long-term survival of emergency department patients with acute chest pain

To evaluate the long-term prognosis of patients with acute chest pain, prospective clinical data and long-term follow-up data (mean 30.1 +/- 9.4 months) were collected for 1,956 patients who presented to the emergency department of an urban teaching hospital with this chief complaint. During follow-up of the 1,915 patients who were discharged alive from the emergency department or hospital, there were 113 (6%) cardiovascular deaths. No differences were detected in the post-discharge cardiovascular survival rates after 3 years of experience with patients who were discharged from the emergency department with a known prior diagnosis of angina or myocardial infarction (89%) and patients who had been admitted and found to have acute myocardial infarction (85%), angina (87%), or other cardiovascular diagnoses (87%). Patients who were discharged from either the hospital or the emergency department without cardiovascular diagnoses had an excellent prognosis. Multivariate Cox regression analysis identified 5 independent correlates of cardiovascular mortality after discharge: age, prior history of coronary disease, ischemic changes on the emergency department electrocardiogram, congestive heart failure and cardiogenic shock. These findings indicate that the postdischarge cardiovascular mortality of patients with chest pain who are discharged from the emergency department with a known history of coronary disease is similar to that of admitted patients with angina or myocardial infarction. These data suggest that the same types of prognostic evaluation strategies that have been developed for admitted patients with ischemic heart disease should also be considered when such patients present to the emergency department but are not admitted.

Three-year mortality in patients suspected of acute myocardial infarction with and without confirmed diagnosis. The Danish Study Group on Verapamil in Myocardial Infarction

The 3-year mortality from day 15 after admission was evaluated prospectively in 11,345 consecutive patients with chest pain suspected of myocardial infarction--4,265 patients with confirmed diagnosis (AMI) and 7,080 patients without confirmed diagnosis (non-AMI), respectively. The mortality rates per year in the first 3 years in the patients with AMI were 14.2%, 6.9%, and 7.6%, and in the non-AMI patients were 8.8%, 5.8%, and 5.5%. The standardized mortality ratio (SMR) correcting for age and sex differences was calculated. SMR is the ratio between the observed mortality in the study population and the expected mortality in an age- and sex-matched subgroup of the general background population. SMR in the first year was 6.7 (95% confidence limits: 6.2 to 7.2) in AMI and 4.7 (4.4 to 5.1) in non-AMI patients. In the second and third years of follow-up, SMR was 3.0 (2.6 to 3.4) and 2.9 (2.5 to 3.4) in AMI and 2.8 (2.5 to 3.1) and 2.4 (2.1 to 2.8) in the non-AMI patients. It is concluded that in the first 3 years the mortality of non-AMI patients is approximately three times higher than in the general population and very close to the late mortality of AMI patients, suggesting that the majority of non-AMI patients are suffering from ischemic heart disease also. Non-AMI patients should consequently be evaluated carefully prior to discharge.

One-year mortality rate after discharge from hospital in relation to whether or not a confirmed myocardial infarction was developed

Consecutive patients admitted to our hospital with suspected acute myocardial infarction during 21 months were prospectively evaluated. One-year mortality after discharge from hospital was related to whether or not an infarction developed (infarct versus non-infarct patients). Of patients discharged alive after developing an infarct, there was a mortality of 17% (n = 777) versus 12% (n = 1830) (P less than 0.001) for all patients not developing infarction. In a high risk group (any of the following: age greater than or equal to 75 years, previous history of myocardial infarction, diabetes mellitus or congestive heart failure) patients developing infarction had a mortality of 24% (n = 457) versus 17% (n = 1221) for those who did not (P less than 0.001). In a low risk group (none of the high risk criteria), the corresponding mortality was 8% (n = 316) for patients suffering infarction and 3% (n = 603) for those not having infarction (P less than 0.001). The difference in mortality between patients with and without infarction was most marked in women (21% vs 11%; P less than 0.01) and in hypertensives (25% vs 12%; P less than 0.001), but less marked in men (16% vs 13%; NS) and in patients without hypertension (13% vs 12%; NS). Among patients not suffering infarction, mortality was particularly high in those with previous congestive heart failure (23%) and diabetes mellitus (21%).

Did prognosis after acute myocardial infarction change during the past 30 years? A meta-analysis

Much effort has been spent to improve survival after acute myocardial infarction. To investigate how effective this effort has been, a meta-analysis was performed of studies published between 1960 and 1987 concerning mortality after acute myocardial infarction. Thirty-six studies were analyzed. They were classified with respect to deaths in the hospital and at 1 month and the 5-year mortality rate starting at hospital discharge. Mortality was assessed from all studies by comparing studies from different institutions with use of identical inclusion criteria (externally controlled studies) and by analyzing studies reporting on changes in mortality in two or more comparable patient cohorts admitted to the same institution at different time periods (internally controlled studies). Reports on clinical trials (for example, thrombolytic therapy, beta-adrenergic blockade) in acute myocardial infarction were excluded. Average overall in-hospital mortality decreased from 29% during the 1960s to 21% during the 1970s and to 16% during the 1980s. The externally controlled studies also showed a declining trend: from 1960 to 1969, 32%, from 1970 to 1979, 19% and from 1980 to 1987, 15%. The 1-month overall mortality rate decreased from 31% during the 1960s to 25% during the 1970s and 18% during the 1980s externally controlled studies. Most internally controlled studies also showed significant improvement in in-hospital and 1-month survival. In contrast, 5-year mortality after hospital discharge did not significantly decrease (33% from 1960 to 1969 and 33% from 1970 to 1979). It is concluded that in the prethrombolytic era, short-term prognosis after acute myocardial infarction has improved since 1960.(ABSTRACT TRUNCATED AT 250 WORDS)

Outcome of patients who were admitted to a new short-stay unit to "rule-out" myocardial infarction

For emergency room patients with a low probability of acute myocardial infarction, we established a new short-stay coronary observation unit, a 2-bed nonintensive care unit with telemetry monitoring adjacent to the emergency room. Of 512 consecutive admissions to the coronary observation unit, 425 (83%) were discharged home without evidence of acute myocardial infarction or serious complications (mean length of stay, 1.2 days; median length of stay, 1 day); 87 (17%) were transferred to other hospital beds. The rate of acute myocardial infarction was 3%. No deaths and only 1 serious complication occurred in the coronary observation unit. At 6 month follow-up, the cardiac survival rate was 99% for patients sent home directly from this unit. It is concluded that the coronary observation unit is safe and adequate for ruling out acute myocardial infarction in a defined subset of patients. Short-stay units, however, encourage early discharges which, when premature, may miss patients who are at risk of having complications shortly thereafter. Strategies such as mandatory but expeditious predischarge stress testing to encourage early but not premature discharge may augment the efficiency of coronary observation units.

Ruling out acute myocardial infarction. A prospective multicenter validation of a 12-hour strategy for patients at low risk

BACKGROUND

Although previous investigations have suggested that 24 hours is required to exclude acute myocardial infarction in patients who are admitted to a coronary care unit for the evaluation of acute chest pain, we hypothesized that a 12-hour period might be adequate for patients with a low probability of infarction at the time of admission.

METHODS

Using a Bayesian model, we developed a strategy to identify candidates for a shorter period of observation from an analysis of a derivation set of 976 patients with acute chest pain who were admitted to three teaching and four community hospitals. In the derivation set, patients whose clinical characteristics in the emergency room predicted a low (less than or equal to 7 percent) probability of myocardial infarction had only a 0.4 percent risk of infarction if they had neither abnormal levels of cardiac enzymes nor recurrent ischemic pain during the first 12 hours of hospitalization. In an independent testing set of 2684 patients from the seven hospitals, 957 admitted patients (36 percent) were classified as candidates for this 12-hour period of observation according to a previously published multivariate algorithm. Few of these patients were actually transferred from a monitored setting at 12 hours.

RESULTS

Of the 771 candidates for a 12-hour period of observation who did not have enzyme abnormalities or recurrent pain during the first 12 hours, 4 (0.5 percent) were subsequently found to have acute myocardial infarction, and only 3 (0.4 percent) died after primary cardiac arrests, all of which occurred three to five days after admission. Rates of other major cardiovascular complications were low in the patients who might have been transferred from the coronary care unit after 12 hours with this strategy. In patients with a higher initial risk of infarction, the standard strategy of 24-hour observation identified all but 11 of 739 acute myocardial infarctions (1 percent).

CONCLUSIONS

Emergency room clinical data can be used to identify a large subgroup of patients for whom a 12-hour period of observation is normally sufficient to exclude acute myocardial infarction. Patient-specific evaluation and treatment can then proceed without the restrictions imposed by "rule-out" protocols for myocardial infarction.

Mortality and morbidity during one year of follow-up in suspected acute myocardial infarction in relation to early diagnosis: experiences from the MIAMI trial

From a large randomized multicentre trial of metoprolol in suspected acute myocardial infarction (n = 5778) we report on the outcome during 1 year of follow-up, in relation to early diagnosis. Patients who developed a confirmed infarction had a 1-year mortality rate of 12.8%. This was significantly higher than the mortality rate of 6.3% (P less than 0.001) in patients with possible infarction and it was also higher than that in patients with no infarction, which was 5.0% (P less than 0.001). A multivariate analysis showed that independent risk predictors in the clinical history of patients without confirmed infarction were a history of angina pectoris, chronic use of digitalis and advanced age. After 1 year, angina pectoris was most common in patients with an initial possible infarction. These patients were also in most urgent need of bypass surgery. We thus conclude that the mortality during 1 year of follow-up among patients with an initially strongly suspected acute myocardial infarction was clearly related to whether or not the patient developed a myocardial infarction.

Does the emergency room electrocardiogram identify patients with suspected myocardial infarction who are at low risk of acute complications?

To determine the early morbidity of patients admitted to the coronary care unit (CCU) with inconclusive evidence of acute myocardial infarction, the prognostic value of the emergency room electrocardiogram (ECG) was examined prospectively in a blinded fashion in 410 patients presenting with acute chest pain. One hundred and forty one patients (34.4%) had an ECG that was normal, showed ST segment changes less than 1 mm, or was unchanged from a previous recording (group 1). The remaining patients (65.6%, group 2) had ECGs considered abnormal. Thirty-nine patients in group 1 and 226 in group 2 had confirmed infarction. There was one CCU death in group 1 (0.7%) versus 27 (10.0%) in group 2 (p less than 0.001) and the overall hospital mortality for group 1 was 2.1% versus 13.0% in group 2 (p less than 0.001). Twenty-eight patients (19.9%) from group 1 suffered complications in the CCU versus 155 (57.6%) from group 2 (p less than 0.001). No life-threatening arrhythmias occurred in group 1 versus occurrence in 47 patients (17.5%) in group 2 (p less than 0.001). The need for acute intervention was also less for group 1 versus group 2 patients, 14 (9.9%) and 85 (31.6%) respectively (p less than 0.001) with no patient requiring electrical cardioversion in group 1. It is concluded that the emergency room ECG can reliably identify a group of low risk patients presenting with suspected myocardial infarction and so help in establishing priority for admission to the CCU. Furthermore, the risk-benefit of thrombolytic therapy in these low risk patients appears unacceptable.

The prognosis of patients suspected of having acute myocardial infarction subsequent to its exclusion as the diagnosis

This review of the literature concerns the prognosis of patients suspected of having myocardial infarction subsequent to its exclusion as the diagnosis. Several investigations show a surprisingly bad prognosis for patients in this category, almost comparable to that of patients with a confirmed infarction. When the results of the different studies are pooled, however, there is a significant difference between those patients with true infarction, and those in whom infarction was excluded, in terms of overall mortality (12% and 7%; P less than 0.0001) and the development of subsequent non-fatal infarction (11% and 6%; P less than 0.05) when the results are analysed for a period of follow-up of one year. The difference was significant even when both fatal and non-fatal infarctions were taken into account over the one-year period of follow-up (13% and 8%; P less than 0.0001). The analysis shows that electrocardiographic ST-T changes are a risk factor for coronary events, but the results are conflicting for other possible risk factors. The selection of patients varies between the different studies, which probably contributes to the different results reported. Prospective studies with well defined groups of patients large enough to permit analysis of subgroupings will be needed to resolve the outstanding questions.