Download Acute Pericarditis

HISTORY
38-year-old man.
CHIEF COMPLAINT: Severe chest pain of several hours duration.
PRESENT ILLNESS: The patient was awakened from sleep by substernal
chest pain. The pain is “sharp,” is enhanced by breathing and improved by
sitting up. He recently recovered from an upper respiratory infection. There is
no history of trauma, chest surgery, tuberculosis, drug abuse or blood
transfusions. He has a history of hypertension treated with a beta-adrenergic
blocking drug. There are no other risk factors for coronary disease.
Question:
What diagnostic possibilities are suggested by this history?
30-1
Answer:
The most likely diagnoses include pericarditis, pneumonia and
pulmonary embolism. Acute myocardial infarction and aortic dissection
are other possibilities.
Additional causes of acute chest pain
include musculoskeletal disorders, spontaneous pneumothorax and
gastrointestinal disorders.
Acute pericarditis is the most likely cardiac diagnosis because of the “pleuritic”
and positional characteristics of the chest pain in a patient with a recent viral
upper respiratory infection. Acute myocardial infarction remains a diagnostic
consideration, especially since infarction can be complicated by pericarditis. In
any patient with chest pain and a history of hypertension, aortic dissection
should be considered.
Proceed
30-2
PHYSICAL SIGNS
a. GENERAL APPEARANCE - Diaphoretic, anxious man leaning forward
(temperature = 100.4º).
b. VENOUS PULSE - The CVP is estimated to be 5 cm of H2O.
URSE
PHONO
S2
S1
S2
S1
a
h
c
JVP
x
Question:
S2
S1
a
v
y
What is your interpretation of the venous pulse?
30-3
Answer:
The venous pulse is normal in mean pressure and wave form.
Although this wave form is different from that seen in some normal patients, it is
commonly seen, especially in young healthy individuals with slow heart rates.
A small “a” wave due to right atrial contraction precedes a prominent systolic “x”
descent due to atrial relaxation that is interrupted by the “c” wave transmitted
from the carotid. Next, the small “v” wave reflects passive filling of the right
atrium, and the “y” descent reflects emptying of the right atrium after the
tricuspid valve opens. The “h” wave follows, due to continued gradual filling of
the right heart in mid to late diastole. The “h” and “a” waves are subtle, and the
following “x” descent stands out as the dominant event in this variant
of
normal.
Proceed
30-4
c. ARTERIAL PULSE - (BP = 130/85 mm Hg)
UPPER RIGHT
STERNAL
EDGE
S1
S2
CAROTID
ECG
Question:
How do you interpret the blood pressure and arterial pulse?
30-5
Answer:
The blood pressure and arterial pulse contour are normal.
d. PRECORDIAL MOVEMENT
PHONO
UPPER RIGHT
PHONO
STERNAL
UPPER RIGHT
EDGE
STERNAL
EDGE
S1
S2
APEXCARDIOGRAM
Question:
How do you interpret the apical impulse?
30-6
Answer:
The apical impulse is normal.
e. CARDIAC AUSCULTATION
ECG
0.4 sec
ULSE
S1
S2
S1
A2
P2
LLSE
S1
APEX
S1
S2
S2
EXPIRATION
Question:
S1
S1
S2
S2
INSPIRATION
How do you interpret these acoustic events?
30-7
Answer:
The first and second heart sounds are normal with physiologic
splitting of S2. There are high frequency, scratchy, “to and fro,” systolic and
diastolic rubs along the left sternal border. Only the systolic component is
heard at the apex. The rubs are louder with expiration.
The typical triphasic pericardial friction rub has three components that
correspond to 1) atrial contraction, 2) ventricular contraction and 3) ventricular
relaxation.
Pericardial rubs may be subtle, evanescent and vary with time and respiration.
The rub may only have one or two components. If heard only in systole, it may
simulate a murmur. Repeated careful auscultation with the patient in different
positions and with exaggerated respiration may be required to detect a soft rub.
They may increase, decrease or remain unchanged with breathing.
f.
PULMONARY AUSCULTATION
Question:
How do you interpret the acoustic events in the pulmonary lung
fields?
Proceed
30-8
Answer:
In the left lower lung fields, there is a pleural rub (timed with
inspiration), reflecting pleural involvement in the pericardial inflammatory
process. In all other lung fields, there are normal vesicular breath sounds.
ELECTROCARDIOGRAM
I
II
III
aVR
aVL
aVF
V1
V2
V3
V4
V5
V6
Question:
How do you interpret this electrocardiogram?
30-9
Answer:
The ECG shows diffuse ST elevation with upward concavity, ST
depression in aVR, and PR depression (I, II) without pathologic Q waves of
infarction. These are typical findings of acute pericarditis.
CHEST X RAYS
PA
LATERAL
Questions:
1. How do you interpret the chest X rays?
2. Based on the history, physical examination, ECG and chest X rays, what is
your diagnostic impression?
30-10
Answers:
1. The chest X rays show a mildly enlarged cardiac silhouette with clear
lung fields.
2. The history, physical examination, ECG and chest X rays are consistent
with acute pericarditis.
When acute pericarditis appears in an otherwise healthy individual,
especially with a respiratory or gastrointestinal illness within the preceding
weeks, a viral (Coxsackie A or B, influenza A or echovirus) etiology is most
likely. Other etiologies were ruled out by appropriate laboratory studies
(e.g., AIDS, tuberculosis, uremia, etc.).
Question:
Would an echocardiogram be helpful?
30-11
LABORATORY (continued)
Answer:
Yes.
Echocardiography will identify the presence and
hemodynamic significance of pericardial fluid and determine ventricular
function. The patient’s study is shown below.
TWO DIMENSIONAL ECHOCARDIOGRAM
RV = Right Ventricle
LV = Left Ventricle
Ao = Aorta
LA = Left Atrium
PARASTERNAL LONG AXIS
Question:
How would you interpret this echocardiogram?
30-12
Answer:
This still frame illustrates the posterior echo free space of a
pericardial effusion (PE). The real time study also revealed normal cardiac size
and function.
Question:
Should pericardiocentesis be performed?
30-13
Answer:
Pericardiocentesis is not indicated in this case. In selected
patients, pericardiocentesis will clarify the diagnosis and is indicated to relieve
cardiac tamponade.
Echocardiography will determine the location and amount of fluid, as well as its
hemodynamic significance, i.e., if cardiac tamponade is present. It may also be
used as an accurate guide for pericardiocentesis, a dramatically effective
treatment.
This patient was treated with a non-steroidal anti-inflammatory drug (NSAID),
but his pain increased significantly over the next 48 hours.
Question:
What therapy would you now consider?
30-14
Answer:
Although an NSAID is usually the drug of choice, in more
refractory cases, corticosteroids may be dramatically effective. Occasionally,
prolonged and/or recurrent drug treatment may be indicated.
This patient responded to an NSAID with increasing dosage, and after 24 hours
his chest pain improved.
Question:
Besides recurrence, what are the major complications
of pericarditis?
30-15
Answer:
Two major complications of pericarditis are cardiac tamponade
and constrictive pericarditis.
Tamponade results from the rapid accumulation of pericardial fluid causing
compression of the heart and limitation of ventricular filling. The clinical
presentation may be dramatic. The classical history is that of progressive
shortness of breath. Hallmarks on physical exam include sinus tachycardia,
elevated central venous pressure, and a paradoxical arterial pulse.
Question:
What is a paradoxical arterial pulse?
30-16
Answer:
Systolic blood pressure falls during inspiration due to a drop in
intrathoracic pressure, pooling of blood in the pulmonary vessels and a
decrease in left ventricular filling. Normally, the magnitude of this change is
less than 10 mm Hg, while in tamponade the drop is greater. This is called a
paradoxical pulse, a misnomer since it is an exaggeration of the normal
inspiratory drop in systolic blood pressure.
In tamponade there is a high intrapericardial pressure limiting total cardiac
filling. Since inspiration increases right heart filling, the result is an obligatory
greater than normal inspiratory decrease in left heart filling, stroke volume and
systolic blood pressure.
A paradoxical pulse is not pathognomonic of tamponade; e.g., it may be seen
in obstructive pulmonary disease, constrictive pericarditis, restrictive
cardiomyopathy and hypovolemic shock.
Proceed
30-17
The other major complication of pericardial disease is constrictive pericarditis.
In constrictive pericarditis, a fibrotic, thickened and adherent pericardium
prevents diastolic filling of both ventricles. It is usually a late complication of
pericarditis. Gradually progressive dyspnea, peripheral edema and ascites are
common. Additional findings may include atrial fibrillation, a narrow pulse
pressure, an elevated central venous pressure with rapid and deep “x” and “y”
descents, the absence of precordial impulses and a pericardial “knock”
on auscultation.
Proceed
30-18
SUMMARY
The pericardium consists of an outer (parietal) layer and an inner (visceral)
layer. There is normally less than 50 ml of fluid in the pericardial space.
Pericardial disease may present as an inflammatory lesion (acute or subacute),
pericardial effusion (with or without cardiac tamponade) or chronic
pericardial constriction.
Acute viral pericarditis is an inflammatory disease that is usually benign and
responds well to anti-inflammatory agents. The majority of cases are
idiopathic, although a viral etiology is also suspected in these patients.
Other infectious agents may also cause pericarditis, as may immune disorders,
drugs, or metabolic diseases of contiguous structures.
An example of the gross pathology follows.
30-19
PATHOLOGY
This is a specimen showing a hemorrhagic pericardial effusion (solid arrow) in
a case where there is also left ventricular hypertrophy (dotted arrow).
Proceed for Case Review
30-20
To Review This Case of
Acute Pericarditis:
The HISTORY is typical for the pain of pericarditis, with a preceding viral
upper respiratory infection.
PHYSICAL SIGNS
a. The GENERAL APPEARANCE reveals an acutely ill man, leaning
forward to relieve his chest pain.
b. The JUGULAR VENOUS PULSE
wave form.
is normal in mean pressure and
c. The BLOOD PRESSURE and CAROTID ARTERIAL PULSE
are normal.
d. PRECORDIAL movement is normal.
Proceed
30-21
e. CARDIAC AUSCULTATION reveals a triphasic pericardial friction
rub that is maximum at the lower left sternal edge and varies with
respiration. At the apex, only the systolic component is heard.
f. PULMONARY AUSCULTATION reveals a pleural rub in the left lower
lung fields, reflecting pleural involvement in the pericardial inflammatory
process. In all other lung fields, there are normal vesicular breath sounds.
The ELECTROCARDIOGRAM
elevation consistent with pericarditis.
The CHEST
clear lung fields.
X RAYS
shows
diffuse
ST
segment
show a mildly enlarged cardiac silhouette with
LABORATORY STUDIES include the echocardiogram that shows
a small pericardial effusion.
TREATMENT consists of anti-inflammatory agents.
30-22