Acute Chest Pain Syndromes Research Articles

Influence of Implementation of a Chest Pain Unit on Acute Coronary Syndrome Outcomes

Different strategies have been described to increase promptness and efficiency in the assessment and management of patients with acute chest pain and acute coronary syndrome (ACS) in the emergency department (ED). The objective of this study is to evaluate the results of implementing a Chest Pain Unit (CPU) to assist patients with ACS, and to determine its impact on quality of health care indexes and clinical outcomes. A study was conducted with a prospective cohort of patients admitted to the ED with a chief complaint of acute chest pain or suspected ACS at two different time periods: before (n = 663) and after (n = 450) introducing a CPU as part of the ED. Quality-of-care indexes analyzed in this study were adherence to a critical pathway, length of hospital stay, and hospital mortality. There was increased adherence to a critical pathway during the CPU period compared to the period with no designated CPU area, including compliance with prescribing aspirin, beta-blockers, and angiotensin-converting enzyme inhibitor, and performing coronary angiography in high-risk patients. After adjustment to baseline characteristics, admissions to a CPU resulted in a 65% reduction in mortality (odds ratio 0.35; 95% confidence interval 0.14-0.88; p = 0.03). There was no difference in median length of hospital stay, 7 days (interquartile range [IQR] 4-12) before CPU and 6 days (IQR 4-11) after introducing the CPU (p = 0.10). In the scenario of a crowded ED, implementation of a CPU was associated with greater adherence to a critical pathway for patients with ACS, with a concomitant reduction in mortality rates.

Triple-Rule-Out CT Angiography for Evaluation of Acute Chest Pain and Possible Acute Coronary Syndrome

Triple-rule-out (TRO) computed tomographic (CT) angiography can provide a cost-effective evaluation of the coronary arteries, aorta, pulmonary arteries, and adjacent intrathoracic structures for the patient with acute chest pain. TRO CT is most appropriate for the patient who is judged to be at low to intermediate risk for acute coronary syndrome (ACS) and whose symptoms may also be attributed to acute pathologic conditions of the aorta or pulmonary arteries. Although a regular cardiac rhythm remains an important factor in coronary CT image quality, newer CT scanners with 64 or more detector rows afford rapid electrocardiographically (ECG) gated imaging to provide high-quality TRO CT studies in patients with a heart rate of up to 80 beats per minute. Injection of iodinated contrast material (< or = 100 mL) is tailored to provide simultaneous high levels of arterial enhancement in the coronary arteries and aorta (> 300 HU) and in the pulmonary arteries (> 200 HU). To limit radiation exposure, the TRO CT examination does not include the entire chest but is constrained to incorporate the aortic arch down through the heart. Scanning parameters, including prospective ECG tube current modulation and prospective ECG gating with the "step-and-shoot" technique, are tailored to reduce radiation exposure (optimally, 5-9 mSv). When performed with appropriate attention to timing and technique, TRO CT provides coronary image quality equal to that of dedicated coronary CT angiography and pulmonary arterial images that are free of motion artifact related to cardiac pulsation. In an appropriately selected emergency department patient population, TRO CT can safely eliminate the need for further diagnostic testing in over 75% of patients.

Evaluation of Acute Coronary Syndromes by Cardiac Magnetic Resonance Imaging

The use of cardiovascular magnetic resonance (CMR) imaging for the evaluation of patients with acute chest pain and acute coronary syndromes has great potential. The strength of CMR relies on its ability to provide information on anatomy, physiology, and function in a single scanning session in a noninvasive manner without the need for iodinated contrast, radiation, or the need to undergo invasive procedures. Specifically, with regard to imaging patients with acute chest pain and/or myocardial infarction (MI), CMR has the ability to qualitatively and quantitatively evaluate global and regional right and left ventricular systolic functions, myocardial edema, myocardial perfusion, and myocardial infarct size and transmurality/viability. This review will focus on CMR imaging for the following applications: (1) imaging for the evaluation of ventricular function and infarct size in patients with acute chest pain and/or acute MI, (2) for triage and prognosis of patients presenting to the emergency department with acute chest pain, (3) for evaluating patients after sustaining an acute MI, and (4) for stem cell research.

Response to Letter Regarding Article, “Usefulness of 64-Slice Cardiac Computed Tomographic Angiography for Diagnosing Acute Coronary Syndromes and Predicting Clinical Outcome in Emergency Department Patients With Chest Pain of Uncertain Origin”

We thank Dr Gaibazzi for his interest in our article describing the potential benefits of cardiac multidetector computed tomography (MDCT) in patients referred to the emergency department (ED) for assessment of an acute chest pain syndrome.1 We agree that other modalities may have negative predictive value similar to MDCT, and indeed, comparative studies may be in order. Unfortunately, at the present time, it remains the case that a high proportion of patients with …

Diagnostic Accuracy of Myocardial Hypoenhancement on Multidetector Computed Tomography in Identifying Myocardial Infarction in Patients Admitted With Acute Chest Pain Syndrome

To evaluate prevalence and diagnostic accuracy of myocardial hypoenhancement (MH) using multidetector computed tomography (MDCT) in patients admitted for acute chest pain syndromes. Sixty-nine patients underwent first-pass MDCT, coronary angiography, and echocardiography. Using a standardized analysis protocol, left ventricular short-axis reformations were evaluated for presence, size, and density of MH in 16 myocardial segments. These were correlated with the presence and location of myocardial infarction (MI), regional myocardial dysfunction, and coronary artery disease. Myocardial hypoenhancement was found in acute MI (27/35), healed MI (6/14), unstable angina (3/9), and atypical chest pain (0/11). Sensitivity, specificity, and positive and negative predictive values of MH for diagnosing any MI were 67%, 85%, 92% and 52%, respectively. The presence of MH on MDCT in acute chest pain patients has high positive predictive value and specificity but only moderate sensitivity for presence of acute or healed MI using the strict criteria proposed in this study.

Acute chest pain syndrome: will MRI shake up cardiovascular care in the emergency room?

‘From a research tool used by mainly radiologists as little as 10 years ago, increased involvement of cardiologists into CMR research, the advent of improved hardware and development of highly sophisticated imaging sequences have turned CMR into what can be regarded today as the single most comprehensive imaging method in clinical cardiology.’

Prevalence and Extent of Obstructive Coronary Artery Disease in Patients With Zero or Low Calcium Score Undergoing 64-Slice Cardiac Multidetector Computed Tomography for Evaluation of a Chest Pain Syndrome

We examined the extent of coronary artery disease (CAD) on 64-slice contrast-enhanced multidetector computed tomography in patients who underwent investigation of a chest pain syndrome who had a zero or low coronary calcium score (CS). In 668 consecutive patients with chest pain syndromes (39% with acute presentation, 61% with long-term presentation) who underwent cardiac multidetector computed tomography, we assessed prevalence and severity of coronary stenoses (>or=1 coronary artery stenosis with >or=50% luminal narrowing) in 231 patients (54 +/- 12 years of age, 45% women) with a 0 (n = 125) or low (n = 106) coronary CS. Obstructive (>or=50% lesion) CAD was present in 27 of 231 patients, in 9 of 125 patients (7%) with a 0 CS, in 18 of 106 (17%) with a low CS (1 to 100), and in 14 of 90 patients (16%) with an acute presentation and 13 of 141 patients (9%) with a long-term presentation (p = NS). All patients in the 0 CS group had single-vessel disease, and 9 (50%) with low CS had multivessel disease, with left main involvement in 1. Of the 27 patients with obstructive CAD on multidetector computed tomography, invasive coronary angiography confirmed these findings in 21 of 23 patients (positive predictive value 91%), and 16 (76%) of them (6.9% of the 0 CS and low CS groups) underwent a myocardial revascularization procedure after invasive coronary angiographic concordance. In conclusion, despite the high known negative predictive value of CS for coronary events, a low and even 0 CS does not exclude clinically important obstructive CAD in patients undergoing investigation of an acute or long-term chest pain syndrome. Contrast-enhanced multidetector computed tomography should be the noninvasive computed tomographic test of choice when possible in these patients.

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16-MDCT Coronary Angiography Versus Invasive Coronary Angiography in Acute Chest Pain Syndrome: A Blinded Prospective Study

The purpose of our study was to prospectively evaluate the usefulness of CT coronary angiography versus invasive coronary angiography for the detection of clinically significant coronary artery disease in patients hospitalized for acute chest pain syndrome. Sixty-six consecutive patients (52 men and 14 women; average age, 57 +/- 11 [SD] years) who were hospitalized for acute chest pain syndrome underwent CT coronary angiography and invasive coronary angiography within an average time interval of 4 days. ECG-gated CT coronary angiography was performed with a 16-MDCT scanner (0.42-sec rotation time, 16 x 0.75 mm detector collimation). Beta-blockers were not administered routinely, and thus the average heart rate was 71 +/- 11 beats per minute. CT coronary angiographic images were evaluated concurrently by two radiologists, who were blinded to invasive coronary angiography results, for stenoses having a diameter of 50% or more, using a 15-segment classification, including all segments 2 mm or more in diameter. The consensus interpretation was compared with results of invasive coronary angiography. CT coronary angiography was technically successful in 59 patients (89%). After exclusion of 20 (3.1%) of 649 coronary segments, which were classified as nonevaluable by CT coronary angiography, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CT coronary angiography for identifying significant coronary artery disease in the remaining 629 coronary segments were 80% (68/85), 89% (482/544), 52% (68/130), 97% (482/499), and 87% (550/629), respectively. The overall accuracy for the main vessels (left main, left anterior descending, left circumflex, and right coronary arteries) was 93%, 88%, 86%, and 86%, respectively. CT coronary angiography using a 16-MDCT scanner enables accurate noninvasive detection of significant coronary artery disease in patients hospitalized for acute chest pain syndrome. Furthermore, relative high sensitivity and specificity of CT coronary angiography can be achieved without pharmacologic manipulation of patient heart rates.

Der extrakardiale Thoraxschmerz

In patients with an acute chest pain syndrome the primary requirement is to diagnose or exclude acute myocardial ischemia or myocardial infarction. However, only 30% of patients admitted and evaluated for chest pain ultimately reveal the diagnosis of acute coronary syndrome. Traditionally,the initial evaluation of patients presenting with chest discomfort or pain to an emergency department or any general practice involves the triad of history, physical examination, and ECG and chest film evaluation.With the diagnostic routine of bedside enzymatic tests for cardiac biomarkers, it has become easier to identify acute coronary syndromes, but at the same time more compelling to pinpoint other differential diagnoses, once coronary syndromes are excluded. When a cardiac origin of any nonsuggestive chest pain syndrome has been excluded, a broad spectrum of other causes for noncardiac chest pain needs to be evaluated. Potential underlying disorders are listed in this overview and grouped according to pathoanatomic origin into aortic, respiratory, and gastroesophageal disorders, musculoskeletal pathology, and somatization disorders. This article reviews both symptoms and diagnostic pathways in patients with noncardiacchest pain,and eventuallyoffersa rational strategy for an efficacious workup of a wide spectrum of important differential diagnoses.

Correlation between coronary angiographic anatomy and troponin I levels in patients with acute chest pain syndrome

Correlation between coronary angiographic anatomy and troponin I levels in patients with acute chest pain syndrome

Is Telemetry Monitoring Necessary in Low-Risk Suspected Acute Chest Pain Syndromes?

Is Telemetry Monitoring Necessary in Low-Risk Suspected Acute Chest Pain Syndromes?

Is Telemetry Monitoring Necessary in Low-Risk Suspected Acute Chest Pain Syndromes?

Non-ICU telemetry monitoring has proven to be a valuable resource for patients suspected of having an acute myocardial infarction. While a significant number of patients are admitted to these units, the actual incidence of events or interventions is low. To identify a subset of patients in whom telemetry monitoring does not alter management. Prospective observational study. Large tertiary care facility. A total of 414 patients consecutively admitted from the emergency department for suspected acute coronary syndromes were studied. Patients were excluded if they presented with ST-segment elevations, were revascularized on hospital admission, were admitted to a surgical service, were transferred from another floor or unit, or remained in the emergency department for the course of the stay. Events were defined as development of myocardial infarction, episodes of chest pain, new or rapid atrial arrhythmias, ventricular arrhythmias, any form of AV nodal block, and asystole. Intervention or change in management was any increase, decrease, or change in medication, cardioversion, electrophysiology study, or transfer to the ICU. Patients who had atypical chest pain and normal ECG findings were significantly less likely to have both intervention and events (4 interventions vs 23 interventions [p < 0.0001], 12 events vs 45 events [p < 0.0001]), compared to those with typical chest pain and abnormal ECG findings. When normal laboratory values were added, only four telemetry events were observed. Patients with atypical chest pain and normal ECG findings represent a subset of patients with low risk for life-threatening arrhythmia. Use of telemetry monitoring in this subset of patients should be reevaluated.

Cardiovascular News

Cardiovascular News

Screening patients with chest pain in the emergency department using electron beam tomography: a follow-up study

OBJECTIVESThe high sensitivity of electron beam tomography (EBT) in the detection of coronary artery calcium (CAC) and obstructive coronary artery disease prompted us to investigate the association between CAC detection and future cardiac events in patients with acute chest pain syndromes requiring hospitalization.BACKGROUNDThree studies have documented that EBT is a rapid and efficient screening tool for patients admitted to the emergency department (ED) with chest pain, but there is a paucity of long-term follow-up data on these chest pain patients.METHODSWe conducted a prospective observational study of 192 patients admitted to the ED of a large tertiary care hospital for chest pain syndromes. Upon admission, patients underwent EBT scanning in addition to the usual care for chest pain syndromes. During the 17-month enrollment period, 221 patients were scanned (54% men with a mean age of 53 ± 9 years). Average follow-up was 50 ± 10 months using chart review.RESULTSFifty-eight patients had coronary events confirmed by a blinded medical record review. The presence of CAC (a total calcium score >0) and increasing score quartiles were strongly related to the occurrence of hard cardiac events including myocardial infarction and death (p < 0.001) and all cardiovascular events (p < 0.001). Stratification by age- and gender-matching further increased the prognostic ability of EBT (for scores above vs. below the age- and gender-matched CAC scores; odds ratio: 13.1, 95% confidence intervals: 5.62, 35.9).CONCLUSIONSThese data support previous reports demonstrating that the presence of CAC in a symptomatic cohort is a strong predictor of future cardiac events. This study supports the use of EBT in a symptomatic cohort with prompt discharge of those patients with negative scans. Furthermore, the absence of CAC is associated with a very low risk of future cardiac risk events in this population over the subsequent seven years (annual event rate <1%).

Role of echocardiography in acute chest pain syndrome

Fewer than one third of patients presenting to the emergency department with complaints of chest pain have an acute coronary syndrome. The electrocardiogram provides a specific diagnosis only in 40% of patients with acute myocardial infarction. The presence of regional wall-motion abnormalities at echocardiography in patients without known coronary artery disease is a moderate indicator of an increased likelihood of acute myocardial ischemia or myocardial infarction with a positive predictive accuracy of about 50%. More important, the absence of regional wall-motion abnormalities identifies a subset of patients unlikely to have a myocardial infarction with a negative predictive accuracy of about 95%. Echocardiography can provide incremental prognostic information to identify patients at risk of early or late cardiac events, even after consideration of clinical, historical, and electrocardiographic variables. The application of new contrast agents to echocardiography will probably allow an early and more accurate evaluation of patients with chest pain of uncertain significance.

Atypical presentation of dissection of the ascending aorta in young men with cystic medial necrosis: Mr findings

Dissection of the ascending aorta is usually associated with severe chest and/or back pain. We describe three young men, with pathologically proven cystic medial necrosis, who presented with atypical clinical symptoms and ascending aortic dissection diagnosed by MR imaging and surgery. Patients with cystic medial necrosis and aortic dissection may not present with a classic acute chest pain syndrome.

Serum Myoglobin as a Biochemical Marker to Rule Out Acute Myocardial Infarction

Background:Diagnosis of AMI in the patients presenting with chest pain of an atypical nature or with a nondiagnostic ECG requires the evaluation of certain biochemical markers. Biochemical markers most often used for the early detection of myocardial damage are CK-MBact, troponin, and myoglobin. The clinical value of measuring serum myoglobin was compared to that of troponin and CK-MBact in the patient with acute chest pain syndrome. Method:We studied timed, sequential measurements of serum myoglobin, CK-MB act and troponin-T obtained from 72 patients who were admitted for the evaluation of suspected AMI within 12 hours after the chest pain onset. Patients with a history of recent trauma, cardiogenic shock, renal failure, or who had received recent cardiopulmonary resuscitation were excluded. We calculated the sensitivity, specificity, negative predictive value, and positive predictive value. Data were analyzed with the Chi-square test for differences in proportion. A value of p<0.05 was considered statistically significant. Result:1) The mean time from symptom onset to arrival at the emergency department was 3.5±0.6 hours. 2) There were no statistical differences in age, sex and risk factors between AMI, angina pectoris and atypical chest pain group. 3) The negative predictive value of myoglobin was significantly higher than those of CK-MB act and troponin-T from 3 to 6 hours after the onset of chest pain. 4) The time to peak of myoglobin level was shorter than those of CK-MBact and troponin-T in AMI patients. Conclusion:Within 3 to 6 hours after the onset of symptoms, myoglobin is a better marker than CKMBact or troponin-T in ruling out AMI for the patient with acute chest pain syndrome. (Korean Circulation J 1998;28(6):915-922)

The role of cardiac troponin T and other new biochemical markers in evaluation and risk stratification of patients with acute chest pain syndromes.

Increased serum creatinine kinase (CK) and CK-MB enzyme levels have been used for years to detect myocardial infarction (MI). However, serum myoglobin and CK-MB mass or protein levels may indicate MI earlier; cardiac troponin T is the most specific marker of myocardial injury and it can detect even minor myocardial necrosis. The diagnostic and prognostic utility of the traditional and new markers of cardiac injury in the emergency evaluation of patients with acute chest pain syndromes were therefore compared. One hundred and fifteen consecutive patients with an acute coronary syndrome, and 64 controls recruited during the same period, were examined. The time elapsed from onset of symptoms to blood collection was recorded. Cardiac markers were measured in specimens collected upon arrival (0 h), and 2 and 5-9 h, and later in cases of longer observation. The major cardiac events occurring up to 40 months after the index examination were recorded. cTnT levels provided unique information: they were the most specific indicators of myocardial damage and identified unstable angina patients at high risk of future major events. Up to 6 h after the onset of chest pain, the new markers were elevated more frequently than the traditional ones and permitted earlier MI recognition. The worst prognosis (nonfatal myocardial infarction or death) was noted in subjects with chest pain at rest within 48 h before the index examination and elevated cTnT levels. The new markers, particularly cardiac troponin T, offer considerable advantages and they should be more widely used in the diagnosis and risk stratification of acute coronary syndromes.

Echocardiographic Prediction of Complications in Patients With Chest Pain

The optimal role of Doppler echocardiography in the evaluation of patients with acute chest pain syndromes is unclear. We prospectively studied a cohort of 466 patients admitted with acute chest pain syndromes to clarify the relation between echocardiographic data and the risk of serious predischarge complications, and to determine if echocardiographic data can provide incremental prognostic information beyond clinical and electrocardiographic variables. Doppler echocardiograms, performed an average of 21 hours after presentation, were independently analyzed by 2 echocardiographers for information on global left and right ventricular function and valvular disease. Regional function was assessed by a wall motion index (WMI). A composite complications end point was positive if significant recurrent myocardial ischemia, heart failure, or arrhythmia developed after the echocardiogram. In univariate analysis, left (odds ratio [OR] 2.9, 95% confidence interval [CI] 1.6, 5.1) and right (OR 2.7, 95% CI 1.2, 6.2) ventricular function, left ventricular end-diastolic (OR 1.6/cm, 95% CI 1.1, 2.3) and end-systolic (OR 1.4/cm, 95% CI 1.1, 1.9) dimensions, and WMI (OR 3.0, 95% CI 1.8, 4.8) predicted complications that developed after the echocardiogram. In multivariate analysis, WMI remained an incremental predictor of risk with an OR of 2.2/unit (95% CI 1.2, 3.9) scaled from 1 to 4. Even in the subset of 403 patients without acute myocardial infarction, WMI was associated with an OR of 1.9 (95% CI 1.0, 3.7). We conclude that early echocardiography provides incremental prognostic information concerning risk of subsequent complications in patients hospitalized with chest pain.In a prospective cohort of 466 patients admitted from the emergency department for chest pain, regional dysfunction by echo was an independent predictor of the risk of in-hospital complications (odds ratio 2.2/unit, 95% confidence interval 1.2, 3.9), even in patients without documented infarction (odds ratio 1.9/unit, 95% CI 1.0, 3.7). Thus, early echocardiography provides incremental prognostic information on risk of subsequent in-hospital complications; further study of its effect on patient care and the cost-effectiveness of testing is needed.