Acute Pericarditis

Question 1

What is acute pericarditis? When is the term myopericarditis, or perimyocarditis used?

Answer 1

Acute pericarditis refers to inflammation of the pericardial sac.
The term myopericarditis, or perimyocarditis, is used for cases of acute pericarditis that also demonstrate features consistent with myocardial inflammation.

Question 2

Describe the anatomy of the peridcardium?

Answer 2

The pericardium is a fibroelastic sac made up of visceral and parietal layers separated by a (potential) space, the pericardial cavity.
In healthy individuals, the pericardial cavity contains 30 to 50 mL of an ultrafiltrate of plasma.

Question 2

Epidemiology of acute pericarditis

Answer 2

Acute pericarditis is the most common disorder involving the pericardium.
Epidemiologic studies are largely lacking, and the exact incidence and prevalence of acute pericarditis are unknown.
However, It is recorded in approximately 0.1 to 0.2 percent of hospitalized patients and 5 percent of patients admitted to the emergency department for non-ischemic chest pain.

Question 2

What is the aetiology of acute pericarditis?

Answer 2

In developed countries, most cases of acute pericarditis are considered of possible or confirmed viral origin

It may be either the first manifestation of an underlying systemic disease or represent an isolated process

The aetiology of most cases remains undetermined following a traditional diagnostic approach

Patients with HIV infection treated with antiretroviral therapy who develop acute pericarditis have an etiologic spectrum very similar to non-HIV-infected patients.

However, HIV infection itself, along with tuberculosis, persist as major causes of acute pericarditis in developing countries or in patients without access to antiretroviral therapy.

Question 3

causes of acute pericarditis

Answer 3

Idiopathic causes
Infectious conditions - viral, bacterial, and tuberculous infections
Inflammatory disorders - RA, SLE, scleroderma, and rheumatic fever
Metabolic disorders - Renal failure and hypothyroidism
Cardiovascular disorders - Acute MI, Dressler syndrome, and aortic dissection
Miscellaneous causes - iatrogenic, neoplasms, drugs, irradiation, sarcoidosis, cardiovascular procedures, and trauma

Question 4

Clinical features of acute pericarditis

Answer 4

Can be nonspecific.
Depends on the underlying aetiology.

Common clinical manifestations include:
* chest pain (typically pleuritic)
* pericardial friction rub (an abnormal heart sound heard when the pericardium becomes inflamed. It occurs as the inflamed layers of the pericardium rub against each other during the heart’s beating cycle (sounds like a scratchy, grating, or squeak))
* characteristic ECG changes (diffuse ST elevation and PR depression) and
* pericardial effusion.

Pericarditis should also be suspected in a patient with:
* persistent fever and pericardial effusion or
* new unexplained cardiomegaly.
* Chest pain
* Pericardial friction rub

Question 4

Describe the chest pain seen in acute pericarditis (SOCRATES)

Answer 4

• S: Typically fairly sudden in onset
• O: occurs over the anterior chest
• C: most often sharp and pleuritic ( sharp, stabbing pain in the chest) in nature
• R: Radiation of chest pain to the trapezius ridge has also been considered to be fairly specific for pericarditis
• A: decreases in intensity when the patient sits up and leans forward.
• E: exacerbated by inspiration or coughing

Question 5

Discuss Pericardial friction rub
seen in acute pericarditis

what does it sound like? what it the character or the sound? how can it be heard? what are the 3 phases it is heard it? where is it loudest?

Answer 5

• Highly specific for acute pericarditis.
• Classically, pericardial friction rubs are triphasic, with a superficial scratchy or squeaking quality.
• Pericardial friction rubs are often intermittent, with an intensity that tends to wax and wane, and are best heard using the diaphragm of the stethoscope.
• The classic pericardial friction rub consists of three phases, corresponding to movement of the heart during atrial systole, ventricular systole, and the rapid filling phase of early ventricular diastole.
• Pericardial rubs may be localized or widespread, but are usually loudest over the left sternal border.

Question 6

What is the DIAGNOSTIC EVALUATION of AP?

Answer 6

History and physical examination
Initial testing in all suspected cases:

Question 7

Discuss History and physical examination

Answer 7

This evaluation should consider disorders that are known to involve the pericardium.
The examination should pay particular attention to auscultation for a pericardial friction rub and the signs associated with cardiac tamponade.

Question 8

Discuss Initial testing in all suspected cases

Answer 8

An ECG
Chest radiography
Complete blood count, troponin level, erythrocyte sedimentation rate, and serum C-reactive protein level.
Echocardiography, with urgent echocardiography if cardiac tamponade is suspected. Even a small effusion can be helpful in confirming the diagnosis of pericarditis, although the absence of an effusion does not exclude the diagnosis

Question 9

What will an ECG show in Stage 1?

Answer 9

Stage 1 - seen in the first hours to days
characterized by widespread ST elevation (typically concave up) with reciprocal ST depression in leads aVR and V1.
There is also frequently an atrial current of injury, reflected by elevation of the PR segment in lead aVR and depression of the PR segment in other limb leads and in the left chest leads, primarily V5 and V6.
The TP segment is recommended as the baseline for comparison when measuring both PR and ST segment changes in acute pericarditis.

Question 9

What will an ECG show in Stage 2?

Answer 9

Stage 2 - typically seen in the first week, is characterized by normalization of the ST and PR segments.

Question 9

What will an ECG show in Stage 3?

Answer 9

Stage 3 - characterized by the development of diffuse T-wave inversions, generallyafterthe ST segments have become isoelectric. It is typically seen in the subacute phase, and its duration is not well documented and likely highly variable.

Question 10

What will an ECG show in Stage 4?

Answer 10

Stage 4 - is represented by normalization of the ECG. It can occur directly from stage 1 in self-limited cases or with prompt response to medical therapy.

Question 11

What will an ECHO show?

Answer 11

It is often normal in patients with the clinical syndrome of acute pericarditis unless there is an associated pericardial effusion.
The finding of a pericardial effusion in a patient with known or suspected pericarditis supports the diagnosis.
The absence of a pericardial effusion or other echocardiographic abnormalities does not exclude it.

Question 12

What are some selected additional tests?

Answer 12

Chest radiograph—Typically normal in patients with acute pericarditis. Although patients with a substantial pericardial effusion may exhibit an enlarged cardiac silhouette with clear lung fields.

Cardiac biomarkers—Acute pericarditis may be associated with increases in serum biomarkers of myocardial injury such as cardiac troponin I or T.

Signs of inflammation—These include elevations in the white blood cell count, erythrocyte sedimentation rate, and serum C-reactive protein concentration. While elevation in these markers supports the diagnosis, they are neither sensitive nor specific for acute pericarditis.

Question 13

Follow-up testing should be performed on a case-by-case basis and may include

Answer 13

Blood cultures if fever higher than 38°C (100.4°F), signs of sepsis, or a documented, concomitant bacterial infection (eg, pneumonia).

Viral studies (e.g, culture, polymerase chain reaction, viral serology, etc)are notroutinely obtained, since the yield is low and management is not altered for the vast majority of patients .

Antinuclear antibody (ANA) titer in selected cases (eg, young women, especially those in whom the history suggests a rheumatologic disorder). Rarely, acute pericarditis is the initial presentation of systemic lupus erythematosus (SLE).

Tuberculin skin testingor an interferon-gamma release assay if not recently performed. The interferon-gamma release assay is most helpful in immunocompromised or HIV-positive patients and in regions where tuberculosis is endemic.

Question 14

PERICARDIOCENTESIS AND PERICARDIAL BIOPSY

Answer 14

Studies in patients with acute pericarditis have reported a low yield for diagnostic pericardiocentesis and pericardial biopsy.

However, some authors have advocated for a more extensive use of these techniques for diagnostic purposes.

The majority of patients with uncomplicated acute pericarditis do not require invasive pericardial procedures.

Question 15

Acute pericarditis is usaually an outpatient condition, but what are HIGH RISK FEATURES?

Answer 15

• Fever (>38°C [100.4°F]).
• Subacute course over days to weeks (without acute onset of chest pain).
• Evidence suggesting cardiac tamponade (eg, hemodynamic compromise).
• A moderate to large pericardial effusion (ie, an end-diastolic echo-free space of more than 20 mm).
• Immunosuppressed patients.
• Therapy withwarfarin or non-vitamin K oral anticoagulants.
• Acute trauma.
• Failure to show clinical improvement following seven days of appropriately dosed nonsteroidal anti-inflammatory drug and colchicinetherapy.
• Elevated cardiac troponin, which suggests myopericarditis/perimyocarditis.

Question 16

Treatment?

Answer 16

• Treatment for specific causes of pericarditis is directed according to the underlying cause
• Admit patients with high-risk features
• Strict bed rest
• NSAIDs
• Colchicine -first-line therapy as an adjunct for patients with acute pericarditis, particularly to prevent recurrences.
• Steroids - should not be used for initial treatment of pericarditis unless it is indicated for the underlying disease, the patient’s condition has no response to NSAIDs or colchicine, or both agents are contraindicated

Question 17

Surgical treatment

Answer 17

Surgical procedures for pericarditis include pericardiectomy, pericardiocentesis, pericardial window placement, and pericardiotomy.

Question 18

Differential diagnosis

Answer 18

Myocardial ischemia
Pulmonary embolism: most common finding is sinus tachycardia
Aortic dissection: it can present as a central chest pain that radiates to the back but it will have a different ECG
Gastroesophageal reflux disease
Musculoskeletal pain: on palpation msk- related condition would cause pain whereas AP wouldn’t

Question 19

Risk factors for P.E

Question 20

Cardiovascular risk factors

Answer 20

Non-modifiable
* Family History
* Age
* Ethnicity
* Gender

Modifiable
* Hypertension
* Diabetes
* Stress
* Smoking and alcohol
* Obesity

Question 21

What is the most common cause of pericarditis?

Answer 21

Viral infections (particularly of the upper respiratory tract) which is why a patient can present with a cough and flu

Question 22

A child with no history of cardiovascular risk factors and a recent fever is presented to the clinic with symptoms of MI & AP (e.g. chest pain), how can we differentiate them?

Answer 22

1. It’s a child and MI is more common in adults over 40 yrs
2. No cardiovasular risk factors
3. CRK and Troponin are greatly elevated in MI and typically not elevated in AP

ECG IS USUALLY SIMILAR AND CANNOT FORM THE BASIS OF DIAGNOSIS FOR EITHER

Question 23

What is the meaning of the 4 heart sounds?

Answer 23

S1: Closure of AV valves (mitral/tricuspid), start of systole.
S2: Closure of semilunar valves (aortic/pulmonic), start of diastole.
S3: Rapid ventricular filling (in early diastole).
S4: Atrial contraction against a stiff ventricle (can indicate hypertension or LV hypertrophy)