B P5 C35 Approach to the Patient with Chest Pain Flashcards
Only ___________ of patients with acute chest pain actually have ACS
10% to 15%
The most common serious cause of acute chest discomfort is ______________
Myocardial ischemia or infarction
The classic manifestation of ischemia is ___________
Angina
described as a heavy chest pressure or squeezing, a burning feeling, or difficulty breathing. The discomfort often radiates to the left shoulder, neck, or arm. It typically builds in intensity over a period of a few minutes. The pain may begin with exercise or psychological stress, but ACS most commonly occurs without obvious precipitating factors.
The following pain descriptions uncharacteristic of myocardial ischemia:
Pleuritic pain (i.e., sharp or knifelike pain brought on by r tory movements or coughing)
Primary or sole location of the discomfort in the middle or lower abdominal region
Pain that may be localized by the tip of one finger, particularly over the left ventricular apex
Pain reproduced with movement or palpation of the chest wall or arms
Constant pain that persists for many hours
Very brief episodes of pain that last a few seconds or less
Pain that radiates into the lower extremities
Clinicians should be mindful of “angina equivalents” such as
Jaw or shoulder pain in the absence of chest pain or dyspnea, nausea or vomiting, and diaphoresis
Women, older persons, and individuals with d betes may experience atypical symptoms of myocardial ischemia or infarction
The visceral surface of the pericardium is insensitive to pain, as is most of the parietal surface. Therefore, _____ causes of pericarditis usually cause little or no pain
Noninfectious
In contrast, infectious pericarditis almost always involves the surrounding pleura, so patients typically experience pleuritic pain with breathing, coughing, and changes in position. _____ may induce the pain because of the proximity of the esophagus to the posterior portion of the heart.
Swallowing
Because the central diaphragm receives its sensory supply from the _____, which in turn arises from the _____ cervical segments of the spinal cord, pain from infectious pericarditis is frequently felt in the shoulders and neck. Involvement of the diaphragm more laterally can lead to symptoms in the upper part of the abdomen and back, and thus create confusion with pancreatitis or cholecystitis.
Phrenic nerve
3rd - 5th cervical segments
_________________ causes a sudden onset of excruciating ripping pain, the location of which reflects the site and progression.
Acute aortic dissection
_____ aortic dissection manifests as pain in the midline of the anterior aspect of the chest, and posterior descending aortic dissection causes pain in the back of the chest.
Ascending
Aortic dissections are rare, with an estimated annual incidence of 3 per 100,000, and usually occur in the presence of risk factors, including _____ (for proximal dissections), and _____ (for distal dissections)
Proximal:
Marfan and Ehlers-Danlos syndromes
BAV
Pregnancy
Distal:
Hypertension
Emboli that lead to _____ can cause lateral pleuritic chest pain.
Pulmonary infarction
_____ tends to be associated with a burning midline pain, whereas _____ can cause pain over the involved lung
Tracheobronchitis
Pneumonia
The pain in pneumothorax begins suddenly and is usually associated with dyspnea. ______ pneumothorax typically occurs in tall, thin young men; _____ pneumothorax occurs in the setting of pulmonary disease such as chronic obstructive pulmonary disease, asthma, or cystic fibrosis.
Primary
Secondary
Irritation of the esophagus by _____ can produce a burning dis- comfort that may be exacerbated by intake of alcohol, aspirin, and some foods. Symptoms are often worsened by a recumbent position and are relieved by sitting upright and with acid-reducing therapies.
Acid reflux
_____ of the esophagus can occur in patients who have had prolonged vomiting episodes. Severe vomiting can also result in _____with mediastinitis.
Mallory-Weiss tears
Esophageal rupture (Boerhaave syndrome)
Chest pain caused by _____ usually occurs 60 to 90 minutes after meals and typically responds rapidly to acid- reducing therapies.This pain is generally epigastric in location but can radiate to the chest and shoulders
Peptic ulcer disease
_____ causes a wide range of pain syndromes and generally causes right upper quadrant abdominal pain, but chest and back pain is not unusual. The pain is frequently described as aching or colicky.
Cholecystitis
_____ typically causes an intense, aching epigastric pain that may radiate to the back, with limited relief through acid-reducing therapies
Pancreatitis
Chest pain secondary to _____ is often elicited by direct pressure over the affected area or by movement of the patient’s neck.2The pain itself can be fleeting, or it can be a dull ache that lasts for hours
Musculoskeletal causes
_____ is a major cause of chest discomfort in ED patients. The symptoms typically include chest tightness, often accompanied by shortness of breath and a sense of anxiety, and generally last 30 minutes or longer.
Panic syndrome
When evaluating patients with acute chest pain, clinicians must address a series of issues related to prognosis and immediate management. Even before arriving at a definite diagnosis, high-priority questions include the following:
Clinical stability: Does the patient need immediate treatment for actual or impending circulatory collapse or respiratory insufficiency?
Immediate prognosis: If the patient is currently clinically stable, what is the risk that a life-threatening condition such as ACS, PE, or aortic dissection exists?
Safety of triage options: If the risk for a life-threatening condition is low, is it safe to discharge the patient for outpatient management, or should further testing or observation to guide management be undertaken?
Guide- lines from the ACC/AHA and European Society of Cardiology (ESC)2,24 emphasize that patients with symptoms consistent with ACS should not be evaluated solely on the phone but should be referred to facilities to be evaluated by a physician and undergo a _____.
12-lead electrocardiogram (ECG)
These guidelines also recommend strong consideration of immediate referral to an ED or a specialized chest pain unit for patients with suspected ACS who experience _____.
Transport as a passenger in a private vehicle is considered an acceptable alternative to an emergency vehicle only if the wait would lead to a delay longer than _____ minutes.
Chest discomfort at rest for longer than 20 minutes
Hemodynamic instability
Recent syncope or near-syncope
20-30 mins
Patients with the following chief complaints should undergo immediate assessment by triage nurses and be referred for further evaluation:
Chest pain, pressure, tightness, or heaviness; pain that radiates to the neck, jaw, shoulders, back, or one or both arms
Indigestion or heartburn; nausea and/or vomiting associated
with chest discomfort
Persistent shortness of breath
Weakness, dizziness, lightheadedness, or loss of consciousness
In one analysis with over 54,000 patients, after adjusting for baseline differences, women were ___% less likely to be reviewed within 10 minutes and ___% less likely to be evaluated within an hour presentation. Such observations underscore the need for more systematic and unbiased approaches to initially evaluate chest pain.
18% - less likely to be reviewed within 10 mins
16% - less likely to be evaluated within 1 hr
Chest pain descriptor with the highest positive likelihood ratio for MI
Radiation to the right arm or shoulder (4.7)
ECG finding with the highest likelihood for MI
Any ST-segment elevation
For patients with ongoing chest discomfort, an ECG, which is a source of decisive data, should be obtained within _____ minutes after arrival, and as rapidly as possible for patients who have a history of chest discomfort consistent with ACS but whose discomfort has resolved by the time of evaluation so that patients who might benefit from immediate reperfusion therapy (mechanical or pharmacologic) can be identified
10 mins
The ECG aids in both diagnosis and prognosis. ST segment elevation at least ____ mm in at least2 contiguous leads is required for the diagnosis of STEMI.
ST segment depression as little as _____ mm is suggestive of ischemia.
T wave inversions of at least ____mm can also indicate ischemia but are less specific.
ST elevation: 1 mm
ST depression: 0.5 mm
T wave inversion: 2 mm
Completely normal findings on an ECG do not exclude the possibility of ACS; the risk for acute MI is approximately _____% in patients with a history of CAD and _____% in those with no such history.
4% - with history of CAD
2% - no history of CAD
Patients with normal or nearly normal findings on an ECG, however, have a better prognosis than do those with clearly abnormal ECGs at initial evaluation
Moreover, a normal ECG has a negative predictive value of _____%,regardless of whether the patient was experiencing chest pain at the time that the ECG was obtained
80% to 90% NPV
Diffuse ST-segment elevation and PR-segment depression suggest _____.
Pericarditis
_____ suggest PE (ECG)
Right-axis deviation
Right bundle branch block
T wave inversions in leads V1 to V4
S wave in lead I and Q wave and T wave inversions in lead III
The _____ specificity of cardiac troponins for myocardium rarely gives false-positive increases (i.e.,increase in the absence of myocardial injury).
Rather, elevations in the absence of other clinical data consistent with ACS usually represent true myocardial dam- age from causes other than atherosclerotic plaque rupture
High specificity
_____ MI occurs when there is clinical evidence of myocardial ischemia and an elevated biomarker of necrosis, but in the setting of stable coronary disease with either reduced myocardial oxygen supply (e.g., hypotension, vasospasm, severe anemia) or increased myocardial oxygen demand (e.g., hypertensive crisis, tachycardia, critical aortic stenosis, severe hypertrophic cardiomyopathy, extreme exercise)
Type 2
Sex may have a modest effect on hs-cTn concentrations (approximately ___%) although other factors such as age and renal dysfunction likely have greater impact (approximately ____% in healthy individuals). Sex-specific cutpoints have been examined for troponin assays. Studies evaluating sex-specific cutpoints including lower concentrations for women have found that such an approach may double the diagnosis of MI in women; however, the impact on outcomes of this approach is unclear.
40%
300%
Importantly, routine application of biomarkers to both men and women presenting with chest pain is also critical, with one study showing that women presenting with acute chest pain were ___% less likely than men to have a troponin test performed and were also less likely to be admitted to a specialized care unit and more likely to die
20%
Preferred diagnostic biomarker for AMI
Cardiac troponin
The high specificity of cardiac troponins for m dium rarely gives false-positive increases (i.e., increase in the absence of myocardial injury). Rather, elevations in the absence of other clinical data consistent with ACS usually represent true myocardial damage from causes other than atherosclerotic plaque rupture.
Type 2 MI occurs when there is clinical evidence of myocardial ischemia and an elevated biomarker of necrosis, but in the setting of stable coronary disease with either reduced myocardial oxygen supply (e.g., hypotension, vasospasm, severe anemia) or increased myocardial oxygen demand (e.g., hypertensive crisis, tachycardia, critical aortic stenosis, severe hypertrophic cardiomyopathy, extreme exercise).
_______________relative lack of specificity because it can be found in the skeletal muscle, tongue, diaphragm, small intestine, uterus, and prostate
CK MB
Patients with a ____________________ of ACS should not undergo biomarker measurements because false-positive results could lead to unnecessary hospitalizations, tests, procedures, and complications
Very low probability
European and U.S. guidelines are integrating the advantages of hs-cTn assays, with testing regimens that include measurements at presentation and _____ hours later, and examining both the absolute levels and change over time
1-2 hrs
In some algorithms, a patient with a very low concentration (generally below the limit of detection) can be ruled out with a single hs-cTn measurement at least _____ hours after the onset of chest pain, whereas patients with a low concentration (assay-dependent but generally at or below the 99th percentile upper-reference limit) at baseline require a second sample but can be ruled out in the absence of changes meeting criteria for dynamic injury _____ hours later.
3 hours
1-2 hours
In centers where high-sensitivity assays are not available, serial testing at presentation, and ____________ hours remains the standard of care.
3 - 6 hours
In some algorithms, a patient with a very low concentration (generally below the limit of detection) can be ruled out with a single hs-cTn measurement at least 3 hours after the onset of chest pain, whereas patients with a low concentration (assay-dependent but generally at or below the 99th percentile upper-reference limit) at baseline require a second sample but can be ruled out in the absence of changes meeting criteria for dynamic injury 1 or 2 hours later.
Components of TIMI risk score for Unstable Angina/NSTEMI
ABCDE
Age >/= 65 years
Aspirin use in the last 7 days
Angina, severe (>/= 2 episodes in 24 hours)
Biomarker - positive cardiac marker
Coronary risk factors >/= 3
CAD - stenosis >/= 50%
Deviation - ECG ST deviation >/= 0.5
Components of HEART score
History
ECG
Age
Risk factors
Troponin
A subsequent evaluation of the HEART score and serial high-sensitivity troponin measurements at 0 and 3 hours in patients presenting with suspected ACS (HEART pathway) decreased testing at 30 days by ____%, decreased length of stay by ___ hours, and increased early discharges by ___%
12.1%: Decrease in testing
12 hours: Decrease in length of stay
21%: Increase in early discharge
Patients with _____are at extremely low risk of adverse cardiovascular events and can be discharged
Normal troponin levels
No ECG abnormalities concerning for ischemia
TIMI Risk Score of 0
HEART score of 3 or below
Noninvasive testing is reasonable in patients without biochemical or ECG evidence of ischemia but who are not at very low risk.Outpatient stress testing is a reasonable option if the patient is at low risk for ACS and if the testing can be accomplished within ___ hours; such a strategy has been shown to be safe.
72 hours
True or False
Patients with normal troponin levels, no ECG abnormalities concerning for ischemia and a TIMI Risk Score of 0, or a History, Electrocardiogram, Age, Risk factors, and initial Troponin (HEART) score of ≤3 are at extremely low risk of adverse cardiovascular events and can be discharged.
True
Outpatient stress testing is a reasonable option if the patient is at low risk for ACS and if the testing can be accomplished within _________
72 hours
Noninvasive testing is reasonable in patients without biochemical or ECG evidence of ischemia but who are not at very low risk.
Give the Indications for Exercise Electrocardiographic Testing in the Emergency Department (ED):
No evidence of myocardial injury by serial troponin (see section on biomarkers)
ECG at the time of arrival and preexercise 12-lead ECG show no significant abnormality
Absence of rest electrocardiographic abnormalities that would preclude accurate assessment of the exercise ECG
From admission to the time that results are available from the second set of cardiac enzymes: patient asymptomatic, lessening chest pain symptoms, or persistent atypical symptoms
Absence of ischemic chest pain at the time of exercise testing
Give the contraindications to exercise testing in the ED
New or evolving electrocardiographic abnormalities on the rest tracing
Abnormal cardiac enzyme levels
Inability to perform exercise
Worsening or persistent ischemic chest pain symptoms from admission to the time of exercise testing
Clinical risk profiling indicating that imminent coronary angiography is likely
Multiple studies have demonstrated that in low-risk patients, exercise testing is safe and has a negative predictive value of typically greater than ___%, although the positive predictive value is frequently less than ___% (depending on the prevalence of ACS in the tested population)
99%
50%
For low-risk patients with no evidence of myocardial ischemia after serial ECGs and biomarkers, outpatient stress testing ideally within ____ hours, and no later than 72 hours, is safe.
24 hours
72 hours
High-risk rest perfusion scans are associated with an increased risk for major cardiac complications, whereas patients with low-risk scans have low 30-day cardiac event rates (<____%)
<2%
The sensitivity of stress echocardiography appears to be comparable to that of myocardial perfusion imaging (_____%), and its specificity is somewhat better (_____% versus 75% to 90%).
MPI:
Sensitivity: 85-90%
Specificity: 90-95%
Myocardial contrast- enhanced echocardiography using microbubble imaging agents offers reasonable (77%) concordance with radionuclide scanning, and the combination of regional wall motion abnormalities and reduced myocardial perfusion has a sensitivity of _____% and a specificity of ____% for ACS
Sensitivity: 80-90%
Specificity: 60-90%
In a study that used cardiac MRI to quantify myocardial perfusion, ventricular function, and hyperenhancement in patients with chest pain, the sensitivity for ACS was ___% and the specificity was ___%.
The addition of T2-weighted imaging, which can detect myocardial edema and thus help differentiate acute from chronic per- fusion defects, improves the specificity to 96% without sacrificing sensitivity.
MRI:
Sensitivity: 84%
Specificity: 85%
Addition of T2WI
Specificity: 96%
Using multidetector computed tomography, coronary CTA has a sensitivity of greater than __% and a specificity of___% for coronary stenosis greater than 50%
Sensitivity: >90%
Specificity: 65-90%
An observational cohort study evaluated the combination of _____ relative to conventional troponin and CCTA looking at traditional features of CAD (no CAD, nonobstructive CAD, 50% stenosis) and found greater diagnostic accuracy for ACS using high-sensitivity troponin and advanced CTA assessment.
hs-cTn at presentation
and
CCTA looking at advanced features of CAD (50% stenosis, high-risk plaque features: positive remodeling, low <30-Hounsfield units plaque, napkin- ring sign, spotty calcium)
Another advantage of CTA is that it is often the test of choice for PE and for aortic dissection, and thus so-called _____ CTA can be performed to evaluate coronary disease, PE, and aortic dissection
Triple-rule-out
