Part 1
Cardiovascular
1
Chapter
1 Chest Pain
In diagnosing the patient with chest pain, it often CHD, even if the story is atypical. CHD is uncommon
helps to categorize the pain by its pathophysiology. (but not unheard of) before 40 years of age, and men
Inflammation of serous surfaces leads to pleuritic are at greater risk than women until approximately 65
pain, characterized by increased pain with inspiration years of age. Cocaine abuse is an important considera-
or cough. This pain may also be aggravated by move- tion, especially in patients with no other cardiac risk
ment or position. Pleuritic pain can be seen in pul- factors.
monary etiologies, pericarditis, and musculoskeletal
disorders. Visceral pain, such as in myocardial is-
chemia and esophageal disease, often produces dull,
CLINICAL MANIFESTATIONS
aching, tight, or sometimes burning pain that is
poorly localized. HISTORY
The most important decision for the physician
is to distinguish life-threatening causes, such as The following diseases often present with the sharp
myocardial ischemia, pulmonary embolus, and aortic pleuritic type of pain. Pneumothorax has an acute
dissection, from non–life-threatening causes. The key onset and is pleuritic and associated with dyspnea.
to identifying the etiology of the pain often lies in the This occurs mostly in young patients (spontaneous)
patient’s history. or those with underlying lung disease (secondary to
blebs). Pulmonary embolism has symptoms similar
to pneumothorax with pleurisy and dyspnea. Risk
factors should be taken into account (see Chapter
RISK FACTORS
16). The pain in pericarditis is pleuritic and posi-
tional, typically relieved by sitting forward.
In evaluating patients with chest pain, certain risk
Substernal pain in pericarditis may radiate to the
factors may increase the suspicion for coronary heart
shoulder/trapezius because of diaphragmatic/phrenic
disease (CHD) and include the following:
nerve irritation.
• Diabetes mellitus In contrast, other diseases may produce a more
• Smoking visceral type of pain, aching, and poorly localized.
• Hypertension Patients with myocardial ischemia often present
• Dyslipidemia with a sensation of squeezing or pressure and possi-
• Family history of CHD bly with a burning sensation. Classic myocardial
ischemic discomfort is located substernally and radi-
Abdominal (central) obesity is associated with in- ates to the ulnar aspect of the left arm, but it may
creased CHD risk and contributes to multiple other also be felt in the jaw, shoulders, epigastrium, or
CHD risk factors. Patients with chest pain and many back. Brought on by exertion or emotional stress,
cardiovascular risk factors require further workup for stable angina usually lasts only minutes. Worrisome
2
Chapter 1 / Chest Pain • 3
features include prolonged pain (more than 20 min- DIAGNOSTIC EVALUATION
utes) with myocardial infarction and rest pain with
unstable angina. Aortic dissection presents with The initial history and physical examination should
abrupt pain that is most intense at onset, which guide the diagnostic workup. If the chest pain ap-
distinguishes this “must-not-miss” diagnosis. Pain is pears cardiac in nature, an electrocardiogram should
often tearing and radiates to the back. In gastroin- be obtained. Furthermore, in those patients with a
testinal disease (such as reflux and esophageal high probability of underlying CHD (patients over
spasm), symptoms may be relieved with antacids, 50 years old, smokers, etc.), an electrocardiogram
are related to food intake, and are worsened in the (ECG) should be checked even if the story is atypi-
supine position. Esophageal spasm may be difficult cal. Table 1-1 lists some helpful findings. The exer-
to differentiate from angina. cise stress test may be the appropriate next step in
Finally, other conditions may have a component of patients with a chronic stable pattern of pain when
both types of pain. In musculoskeletal disorders, pain angina is suspected (see Chapter 3).
is more easily localized and worsens with movement In patients with pleuritic pain and dyspnea as pre-
or palpation. Pain ranges from darting, lasting sec- dominant symptoms, a chest radiograph should be
onds, to a prolonged dull ache that lasts for days. In the initial step to rule out pneumothorax, pulmonary
the neuropathic pain of herpes zoster, because pain infiltrates, and rib fractures. A widened mediastinum
may precede rash by several days, a burning sensation on chest radiograph may be seen with aortic dissec-
in a dermatomal distribution is a key feature. With tion. Chest radiograph findings seen in pulmonary
anxiety, pain is often atypical and prolonged, and embolism can be found in Chapter 16.
workup reveals no other cause. Other important diagnostic tests include the chest
computed tomography (CT), by which patients with
PHYSICAL EXAMINATION worrisome histories for aortic dissection should be
further evaluated regardless of chest radiograph or
Remember that a patient with ischemic heart disease ECG results. Magnetic resonance imaging (MRI) is a
may present (and often does) with a completely normal noninvasive diagnostic option for patients stable
physical examination. However, some physical find- enough to be sent into the scanner. Transesophageal
ings may lead to the correct diagnosis.
• Unequal blood pressure between arms is an im-
portant feature for aortic dissection. Tachypnea is TABLE 1-1 Electrocardiogram
seen in pulmonary cases such as pneumothorax or
• Q waves in two or more leads: previous myocar-
pulmonary embolism. dial infarction
• Reproduction of the chest pain by palpation is a
key feature of musculoskeletal causes. This is not • ST depression 1 mm: ischemia
the case in angina, pulmonary embolus, aortic dis- • ST elevation: acute myocardial infarction or
section, or true pleuritic disease. pericarditis (the latter often has involvement of
• Cardiac findings to look for include a fourth heart all leads and associated PR depression)
sound (ischemia), an apical holosystolic murmur • Left bundle branch block: suggests underlying
(ischemic mitral regurgitation), a blowing diastolic heart disease (ischemic, hypertensive)
murmur (aortic regurgitation as a result of aortic • Right bundle branch block: may be indicative of
dissection involving the valve root), and a pericar- right heart strain (as in pulmonary embolus)
dial rub (pericarditis). • T-wave inversions and nonspecific ST changes:
• Pulmonary findings of a pneumothorax include seen in both healthy individuals and in many
hyperresonance to percussion, decreased fremitus, diseases (therefore, not useful)
and tracheal deviation to the opposite side. A
Note: A normal ECG does not rule out ischemia or serious disease,
pleural rub may indicate pulmonary infarction or especially when recorded in the absence of pain. Right bundle branch
pneumonia. Rales and basilar dullness indicate block and early repolarization may be seen in young, healthy, normal
individuals. Occlusion of the right coronary artery by an aortic dissection
congestive heart failure, which may reflect active may present with inferior ST elevation. This is a vital distinction to make.
cardiac ischemia.
4 • Blueprints Medicine
echocardiogram is a minimally invasive and rapid
method of detecting aortic dissection at the bedside.
KEY POINTS
Either helical chest CT or a ventilation-perfusion • Patients with histories suggestive of serious causes
(V/Q) scan is used in patients with pleuritic pain and of chest pain (e.g., ischemia, dissection, embolus)
normal chest radiograph in whom pulmonary embo- deserve further evaluation even if physical examina-
lus is suspected. A helical chest CT is sensitive for tion, chest radiograph, and ECG results are normal.
small pulmonary emboli and may detect other chest • Certain chest pain syndromes have very typical pat-
abnormalities leading to chest pain. A normal V/Q terns, such as the acute tearing pain of aortic dis-
scan rules out the diagnosis of pulmonary embolus, section, the dermatomal distribution of herpes
whereas a high-probability scan confirms the diagno- zoster, or the positional pleuritic pain of pericarditis
sis when accompanied by a high clinical suspicion. (relieved when the patient sits forward).
This is further detailed in Chapter 16. • Risk factors are important to determine the proba-
In chest pain of esophageal origin, pain induced bility of CHD in a patient with chest pain. These
by esophageal reflux may be confirmed by 24-hour include older age, male sex, diabetes mellitus, hy-
esophageal pH monitoring or by an empirical trial pertension, dyslipidemia, smoking, obesity, and
of antacids. The Bernstein test (acid instillation into family history.
the esophagus, reproducing pain) is not commonly
• The ECG is a key test in patients with a suspected
used today. cardiac origin of chest pain. The findings of Q
In the case of suspected musculoskeletal pain in waves, ST elevation, or ST depression all signify car-
the low-risk patient, a trial of nonsteroidal anti- diac ischemia. A notable exception is pericarditis,
inflammatory drugs is appropriate both diagnostically which has diffuse ST elevation, often with associ-
and therapeutically. Pericarditis also responds to this ated PR depression.
treatment.