The diagnoses of patients admitted with acute chest pain but without myocardial infarction

OBJECTIVE: The purpose of this study was to describe the frequencies ofvarious diagnoses in patients admitted with acute chest pain,but without acute myocardial infarction, and to evaluate a non-invasivescreening programme for these patients. PATIENTS: A total of 204 consecutive non-acute myocardial infarction patientswere included. Fifty-six had a definite diagnosis within 48h, whereas 148 patients underwent an examination programme includingpulmonary scintigraphy, echocardiography, exercise electrocardiography,myocardial scintigraphy, Holter monitoring, hyperventilationtest, oesophago-gastro-duodenoscopy, 3 h monitoring of oesophagealpH, oesophageal manometry, Bernstein test, physical examinationof the chest wall and thoracic spine, bronchial histamine provocationtest and ultrasonic examination of the abdomen. RESULTS: According to predefined criteria, 186 patients (91%) had atleast one diagnosis, 144 had one, whereas 39 had two, and threepatients had three diagnoses. In 18 patients no diagnosis wasobtained. The diagnoses belonged mainly to three groups: (1)ischaemic heart disease (n=64); (2) gastro-oesophageal diseases(n=85); (3) chest-wall syndromes (n=58). Less frequent diagnosesincluded pulmonary embolism, pleuritis/pneumonia, lung cancer.aortic stenosis, aortic aneurysm and herpes zoster. CONCLUSIONS: The high risk subset of a non-acute myocardial infarction populationcan be identified by means of a clinical evaluation and non-invasivecardiac examinations. Among the remainder, pulmonary embolism,gastro-oesophageal diseases and chest-wall syndromes shouldbe paid special attention. A careful physical examination ofthe chest wall and an upper endoscopy seems to be the most cost-beneficialexamination to employ in this subset.     

Effect of intravenous metoprolol before hospital admission on chest pain in suspected acute myocardial infarction

BACKGROUND: The aim of this study was to describe the effect of intravenous metoprolol on the intensity of chest pain before hospital admission in patients with suspected acute myocardial infarction AMI). METHODS AND RESULTS: Two hundred sixty-two patients with acute chest pain and suspected AMI were randomly assigned before hospital admission to either 5 mg morphine plus metoprolol 5 mg x 3 intravenously or 5 mg morphine plus intravenous placebo. Chest pain was evaluated on a 10-grade scale before and for 60 minutes after intravenous injection. One hundred thirty-four patients were randomly assigned to metoprolol and 128 to placebo. Among all patients randomized to metoprolol, the mean chest pain score was reduced by 3.0 +/- 1.9 arbitrary units AU) from before to after intravenous injection compared with 2.6 +/- 2.1 AU for placebo not significant). Among patients with an initially confirmed or strong suspicion of AMI, the corresponding figures were 3.1 +/- 1.8 AU for metoprolol and 2.2 +/- 1.6 AU for placebo P =.02). Among patients with only a vague or moderate suspicion of AMI, there was no difference. The treatment was well tolerated. CONCLUSIONS: When all patients were included in the analyses, there was no significant difference with regard to reduction of chest pain in the patients randomly assigned to metoprolol compared with placebo. A retrospective subgroup analysis indicated a beneficial effect of metoprolol among patients with an initially strong suspicion of or confirmed AMI. Further investigations are warranted to confirm this finding.     

Prognosis for patients with initially suspected acute myocardial infarction in relation to presence of chest pain.

In all 4,232 patients admitted to a single hospital during a 21-month period due to initially suspected acute myocardial infarction (AMI), the prognosis and risk factor pattern were related to whether patients had chest pain or not. Symptoms other than chest pain that raised a suspicion of AMI were mainly acute heart failure, arrhythmia, and loss of consciousness. In 377 patients (9%) symptoms other than chest pain raised an initial suspicion of AMI. These patients developed a confirmed infarction during the first three days in hospital with a similar frequency (22%) as compared with patients having chest pain (22%). However, patients with "other symptoms" had a one-year mortality of 28% versus 15% for chest pain patients (p less than 0.001). Patients with "other symptoms" more often died in association with ventricular fibrillation and less often in association with cardiogenic shock as compared with chest pain patients. Among the 921 patients who developed early AMI, 64 (7%) had symptoms other than chest pain. They had a one-year mortality of 48% versus 27% for chest pain patients (p less than 0.001). We conclude that in a nonselected group of patients hospitalized due to suspected AMI, those with symptoms other than chest pain have a one-year mortality, which is nearly twice that of patients with chest pain.     

Prognosis and thallium-201 scintigraphy in patients admitted with chest pain without confirmed acute myocardial infarction

Exercise and rest thallium scintigraphy and exercise electrocardiography were performed after discharge in 158 patients aged less than 76 years admitted with chest pain in whom a suspected diagnosis of acute myocardial infarction had not been confirmed. During a follow up of 12-24 months (median 14 months) there were 10 cardiac events--that is, non-fatal acute myocardial infarction or cardiac deaths. Transient thallium defects and abnormal ST response (that is ST segment deviation or uninterpretable ST segment) during exercise were correlated significantly with an unfavourable prognosis. One hundred and four patients with neither of these characteristics were at lower risk of a cardiac event than the 19 patients with both of these characteristics. The percentages of patients in these two groups without a cardiac event after one year were 98.1 and 78.8 respectively. Thallium scintigraphy, alone or in combination with exercise electrocardiography, can be used to identify groups at high and low risk of future cardiac events, in patients with chest pain in whom acute myocardial infarction is suspected but not found.     

Prognosis and thallium-201 scintigraphy in patients admitted with chest pain without confirmed acute myocardial infarction.

Exercise and rest thallium scintigraphy and exercise electrocardiography were performed after discharge in 158 patients aged less than 76 years admitted with chest pain in whom a suspected diagnosis of acute myocardial infarction had not been confirmed. During a follow up of 12-24 months (median 14 months) there were 10 cardiac events--that is, non-fatal acute myocardial infarction or cardiac deaths. Transient thallium defects and abnormal ST response (that is ST segment deviation or uninterpretable ST segment) during exercise were correlated significantly with an unfavourable prognosis. One hundred and four patients with neither of these characteristics were at lower risk of a cardiac event than the 19 patients with both of these characteristics. The percentages of patients in these two groups without a cardiac event after one year were 98.1 and 78.8 respectively. Thallium scintigraphy, alone or in combination with exercise electrocardiography, can be used to identify groups at high and low risk of future cardiac events, in patients with chest pain in whom acute myocardial infarction is suspected but not found.     

Prognostic value of fibrinogen in patients admitted with suspected unstable angina and non-q-wave myocardial infarction

INTRODUCTION AND OBJECTIVE: In recent years, the relation between biological markers of inflammation and prognosis in patients suffering from acute coronary syndromes has been investigated. The aim of this study was to evaluate the association between baseline fibrinogen concentrations and the development of clinical events in patients admitted with suspicion of unstable angina and non-Q-wave myocardial infarction. MATERIAL AND METHOD: Levels of fibrinogen at enrollment were analyzed in 325 consecutive patients with acute coronary syndromes. Fibrinogen values were divided into tertiles and the incidence of clinical events was evaluated at each level. The combination of death and/or myocardial infarction was the main endpoint. RESULTS: Fibrinogen levels were significantly higher in patients who subsequently had myocardial infarction, cardiac death, or both during follow up. The probabilities of death and/or myocardial infarction were 6%, 13%, and 29% (p < 0.0001), respectively, in patients grouped by fibrinogen tertiles (304, 305-374 and 375 mg/dl). Multivariate predictors of combined events were age, previous angina, ST-segment depression in the admission ECG, and fibrinogen into tertiles. The adjusted hazard ratio (95% CI) for patients in the upper tertile was 4.8 (1.6-14; p = 0.004). CONCLUSIONS: High fibrinogen levels were related to a less favorable long-term or short-term outcome in patients admitted for suspicion of unstable angina and non-Q-wave myocardial infarction. This association persists after adjustment for other classical risk factors such as age, prior angina, and ST-segment depression in the ECG.     

Diagnostic value of MPO plasma levels in patients admitted for suspected myocardial infarction

Background

Besides its well-established role in atherosclerosis, myeloperoxidase (MPO) has gained attention as a prognostic indicator in cardiovascular disease. Previous studies assessed MPO retrospectively and at a single time point. The current study aimed to evaluate the prognostic information of MPO prospectively and in consecutive measurements in patients presenting with chest pain.

Methods

MPO plasma levels were determined in 274 consecutive chest pain patients admitted to the emergency room.

Results

A total of 100 patients (36.5%) were finally diagnosed for acute myocardial infarction (AMI). Patients with AMI had significantly higher MPO levels than patients without AMI. Importantly, MPO levels were elevated in patients finally diagnosed for AMI even when troponin I (TNI) was negative (cutoff: 0.032 ng/ml). Overall, MPO yielded a negative predictive value (NPV) of 85.5% (95% confidence interval (CI): 82.6-88.4) and a sensitivity for diagnosing AMI of 80.0% (95% CI: 75.8-84.2) compared to a NPV of 91.7% (95% CI: 89.5-94.0) and a sensitivity of 85.9% (95% CI: 82.3-89.5) for TNI. For patients with a symptom onset of ≤ 2 h the sensitivity of MPO increased to 95.8% (95% CI: 93.7-97.9) whereas the sensitivity of TNI dropped to 50.0% (95% CI: 44.8-55.2). The negative predictive value of MPO for this group of patients was 95.6% (95% CI: 94.0-97.3) compared to 73.3% (95% CI: 69.8-76.9) for TNI.

Discussion

The current data underscore the role of MPO as diagnostic marker in acute coronary disease; however the additive information derived from MPO is restricted to patients presenting in the early phase of symptom onset.     

Japanese patients with acute myocardial infarction who present without chest pain

Previous studies have suggested that patients with acute myocardial infarction (AMI) who presented without chest pain had an unfavorable prognosis due to undertreatment. Despite this, few studies have been conducted on the topic, particularly in Japan. The present analysis aimed at determining whether Japanese AMI patients without chest pain are undertreated and experience higher mortality during hospitalization. Data from the Tokai Acute Myocardial Infarction Study II sample were used, which is a prospective study of all consecutive patients admitted to the 15 acute care hospitals in the Tokai region with the diagnosis of AMI from 2001 to 2003. Data on baseline and procedural characteristics and hospital outcome were collected. Differences in the baseline and procedural characteristics and clinical outcomes between patients presenting with and without chest pain were assessed. We evaluated a total of 1,769 patients who presented with chest pain and 452 who did not. The patients with AMI in the absence of chest pain were older and were more likely to have worse clinical conditions than those with chest pain. They were more likely to be undertreated, although the probability of vasopressor use was higher. The patients without chest pain had a significantly higher in-hospital mortality rate than those with chest pain. According to multivariate analysis, however, chest pain was not identified as an independent predictor of in-hospital death. The results suggest that the higher in-hospital mortality rate among Japanese AMI patients without chest pain could be accounted for by differences in clinical conditions.     

Differentiating ST-elevation myocardial infarction from nonischemic ST-elevation in patients with chest pain

Current guidelines state that patients with compatible symptoms and ST-segment elevation (STE) in ≥2 contiguous electrocardiographic leads should undergo immediate reperfusion therapy. Aggressive attempts at decreasing door-to-balloon times have led to more frequent activation of primary percutaneous coronary intervention (pPCI) protocols. However, it remains crucial to correctly differentiate STE myocardial infarction (STEMI) from nonischemic STE (NISTE). We assessed the ability of experienced interventional cardiologists in determining whether STE represents acute STEMI or NISTE. Seven readers studied electrocardiograms of consecutive patients showing STE. Patients with left bundle branch block or ventricular rhythms were excluded. Readers decided if, based on electrocardiographic results, they would have activated the pPCI protocol. If NISTE was chosen, readers selected from 12 possible explanations as to why STE was present. Of 84 patients, 40 (48%) had adjudicated STEMI. The percentage for which readers recommended pPCI varied (33% to 75%). Readers' sensitivity and specificity ranged from 55% to 83% (average 71%) and 32% to 86% (average 63%), respectively. Positive and negative predictive values ranged from 52% to 79% (average 66%) and 67% to 79% (average 71%), respectively. Broad inconsistencies existed among readers as to the chosen reasons for NISTE classification. In conclusion, we found wide variations in experienced interventional cardiologists in differentiating STEMI with a need for pPCI from NISTE.     

Prospective evaluation of an EDB-based diagnostic program to be used in patients admitted to hospital with acute chest pain

A recently designed computer based decision support system (DSP),almost exclusively based on case history data, was developedto facilitate immediate differentiation between patients withand without urgent need for coronary care unit (CCU) transferralfrom the emergency room, and additionally to distinguish betweenpatients with and without acute myocardial infarction (MI). One-year's prospective testing in a consecutive series of 1252patients with acute chest pain revealed that the DSP, used inaddition to ECG and clinical examination, demonstrated a sensitivityof 96% in the detection of patients in need of CCU observation(MI-sensitivity of 98%), and a specificity of 56% in excludingpatients who were not in need of CCU observation. The proportionof referrals to the CCU judged to be unnecessary was only 17%of the total number of patients seen in the emergency room.     

Management of patients with prolonged ischemic chest pain without acute myocardial infarction

Consecutive patients admitted to a Coronary Care Unit during 1981-1982 were studied. One hundred twenty-eight patients had prolonged ischemic chest pain without developing myocardial infarction. Follow-up information was available in 121 at an average period of 38 months. Thirty-eight patients (32.8%) sustained significant cardiovascular events, including 14 cardiac deaths. Only 15 patients were symptom-free off treatment. Prognosis was best determined from the resting ECG. Transient ST-T wave shifts predicted patients at high risk of further cardiovascular events and allowed selection of a group meriting more intensive treatment.     

Variability of chest pain in suspected acute myocardial infarction according to subjective assessment and requirement of narcotic analgesics

In 653 patients with suspected acute myocardial infarction the course of pain according to subjective assessment and morphine requirement is described. Patients were asked to score pain from 0-10 until a pain-free interval of 12 hours appeared. Different categories of patients constructed from clinical aspects were compared. Although the variability between groups was fairly small, subgroups were found in which the initial intensity of pain was more marked and the duration of pain was longer. Thus patients with larger infarcts according to maximum serum enzyme activity and patients with Q-wave infarction had more severe pain initially and also a longer duration and a higher morphine requirement compared with patients with a lower serum enzyme activity or a non-Q-wave infarction. Other groups with a more severe course of chest pain were those with more intensive pain at home, electrocardiographic signs of acute myocardial infarction on admission to hospital, and finally those with a high systolic blood pressure or a high rate-pressure product on admission to the Coronary Care Unit. We thus conclude that there is a variability of chest pain in suspected acute myocardial infarction and that there are defined groups of patients in which a more severe course of chest pain could be expected.     

Utility and safety of immediate exercise testing of low-risk patients admitted to the hospital with acute chest pain

It is common practice to hospitalize patients with chest pain for a period of observation and to perform further diagnostic evaluation such as exercise treadmill testing (ETT) once acute myocardial infarction (AMI) has been excluded. This study evaluates the safety and efficacy of immediate ETT for patients admitted to the hospital with acute chest pain. One hundred and ninety non-consecutive low-risk patients admitted to the hospital from emergency department with acute chest pain underwent ETT using Bruce protocol immediately on admission to the hospital (median time 165+30 min). Fifty-seven (30%) patients had positive exercise electrocardiograms, 44 (77.2%) of whom had significant coronary narrowing by angiography. An uncomplicated anterior non-Q-wave AMI was diagnosed in one patient. One hundred and eleven (58.4%) patients had negative and 22 (11.6%) patients had non-diagnostic exercise electrocardiograms. Of these 133 patients, 86 (64.7%) were discharged immediately after ETT, 19 (14.3%) were discharged within 24 h, and 28 (21%) were discharged after 24 h of observation. There were no complications from ETT. During the 17+/-6 months follow-up no patients died, and only eight (7.2%) patients with negative ETT experienced a major cardiac event (one AMI and seven angina). In conclusion, our results suggest that immediate ETT of low-risk patients with chest pain who are at sufficient risk to be designated for hospital admission, is effective in further stratifying this group into those who can be safety discharged immediately and those who require hospitalization.     

Late direct angioplasty in patients with myocardial infarction and fluctuating chest pain.

Myocardial infarctions may be associated with reduced but persistent blood flow to the infarct zone. We developed clinical criteria to select patients likely to have persistent perfusion to the infarct zone in the setting of acute myocardial infarction. Twenty-four consecutive patients with fluctuating pain and/or ST segment elevation who presented within 24 hours of the onset of infarction were studied with coronary angiography followed by direct percutaneous transluminal coronary angioplasty. Sixty-seven percent of patients had residual flow to the infarct territory. Eighteen patients had repeat angiography on day 9.4 +/- 4.1, and all arteries were patent (21% +/- 12% stenosis). Ejection fraction had risen from 50.0% +/- 15% to 54.0% +/- 14% (p less than 0.05). At follow-up (9.1 +/- 4.6 months), one patient died of noncardiac causes, and five redeveloped angina and underwent repeat procedures. Patients with fluctuating symptoms and/or ST segments are likely to have residual flow to the infarct zone, and late angioplasty may improve ventricular function in this group.     

HEART风险评分在非心肌梗死性胸痛人群的研究

目的:研究HEART风险评分在非急性心肌梗死性胸痛人群的应用价值。方法:这是一个源于前瞻性获得的数据库的回顾性研究。连续入选2014年9月至2015年2月,在北京安贞医院急诊胸痛中心就诊的胸痛患者。计算HEART评分。研究终点为3个月时主要不良心脏事件。结果:研究总计入选1041名胸痛患者。其中,332名患者发生了主要不良心脏事件。HEART评分的受试者操作特征曲线下面积为0.77(95%CI:0.74~0.80)。随评分增加,主要不良心脏事件显著增加(P0.001)。入选的所有患者分成三组:低危组(评分0~2分),中危组(评分3~4分)和高危组(评分5~8分),主要不良心脏事件发生率分别为1.7%,17.1%和54.6%,各组间差异有统计学意义(P0.001)。不同的组别,给予不同的分诊方案。结论:HEART风险评分可以用于急诊科非急性心肌梗死性胸痛患者的分诊和预后评估。