8/21- Pericardial Diseases Flashcards Preview

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Flashcards in 8/21- Pericardial Diseases Deck (32)

What are the layers of the pericardium?

- Fibrous (mostly acellular)

- Serous: parietal layer

- Serous: visceral layer (epicardium)

Pericardial cavity is between the parietal and visceral portions of the serous pericardium; normally ~50cc of fluid 


What are the 4 basic functions of the pericardium?

1. Restraining effect on cardiac volume

2. Maintain optimal P-V relationships in the cardiac chambers

3. Favor ejection of similar stroke volumes for both ventricles

4. Shield heart against infections from contagious structures


What is a pericardial effusion?

The buildup of fluid within the pericardial space


What are some causes of pericardial effusions?

- Idiopathic (most common)

- Infectious; viral, bacterial, mycobacteria, fungal, protozoal

- Immune/inflammatory: CT disease, arteritis, inflammatory bowel disease, early/late post-MI, drug induced

- Neoplastic disease

- Radiation

- Thyroid disease

- ESRD (end stage renal disease)

- Early post cardiac surgery

- Trauma

- Congenital (e.g. born without pericardium)

- Hemopericardium: trauma, post MI free wall rupture, device or procedure related, dissecting aortic aneurysm


What is cardiac tamponade?

What determines the hemodynamic consequences?

- Reduces the volume of the cardiac chambers such that cardiac output begins to decline

- Continuation from an effusion causing minimally detectable effects to full-blown circulatory collapse

Hemodynamic consequences determined by:

- Intrapericardial pressure

- Ability of the heart to compensate for elevated pressure


What is the body's compensatory response to cardiac tampanode/rapidly accumulating pericardial fluid?

- Increased adrenergic stimulation and PS withdrawal (tachycardia and increased contractility); done to maintain CO

- In terminal stages: depressive reflex = paradoxical bradycardia (about to code)


Hemodynamics of cardiac tamponade?

- Abrupt rise of pericardial pressure

- Rise of atrial and ventricular diastolic pressures (intracardiac pressures)

- Equalization of intracardiac pressures (not normal)

- Loss of y-descent

- Pulsus paradoxus


Describe the negative components of the atrial pressure waveform?

What can indicate pathology?

x-descent: seen when atria are actively relaxing; ventricular contraction

y-descent: occurs during ventricular systole

- blunted in cardiac tamponade because of constriction by pericardial fluid 


What is shown here?

Pulsus paradoxus

- "exaggerated inspiratory drop in SBP > 10 mmHg"

- Hallmark of cardiac tamponade!

(Variation in systemic blood pressure and pulse due to constriction by pericardial fluid of the heart)

- Filling of the L and R sides of the heart become dependent on each other (not normal)- "intra-ventricular dependence"

- During inspiration, negative pressure typically helps right side of the heart fill; in tamponade, filling of the R causes septum to bulge into L side of the heart and decreases SV and CO of L side

(IV shift into LV -> reduced LV EDV -> SV decreases (Frank-Starling law) -> SBP decreases)

- See decrease in BP and pulse during inspiration in cardiac tamponade


Symptoms and PE of cardiac tamponade?

- Pericardial chest pain

- Dyspnea/tachypnea**

- Shock

- Non-specific sense of discomfort (generalized malaise)

- Tachycardia

- Pulsus paradoxus

- Beck's triad: hypotension, muffled heart sounds (due to fluid), elevated JVP (normal decrease on inspiration)


Is pulsus paradoxus always present in cardiac tamponade?


- Severe hypotension of hypovolemia prevents the rise in RV filling in inspiration

- Volume replacement often facilitates its detection


What is seen here? 

Typical of cardiac tamponade/pericardial effusion

- "Electrical alternans"

- QRS varying with every other beat of the heart (due to swinging of heart with large pericardial fluid)


What is seen here?

CXR of pericardial effusion

- Very large, globular heart

- Typically, heart borders should be less than half the thoracic cavity distance


What is seen here? 


Pericardial effusion by echo (diagnostic)

- Dark area on left (blood/fluid) is in the pericardial space


What is constrictive pericarditis?

- Impairment of diastolic filling due to chronic thickening and/or calcification of the pericardium

- Typically a chronic process (where cardiac tamponade was more acute)


Etiology of constrictive pericarditis (causes)?

- Idiopathic (most frequent)

- Infectious: bacterial (TB!, staph aureus, pneumococcus...), viral, fungal, lparasitic

- Irradiation (for Hodgkin's disease or other chest malignancies)

- CT disease: RA, SLE

- Post-hemopericardium (post-op, trauma)

- Uremia (ESRD)

- Neoplastic


What is seen here?

CXR and CT of constrictive pericarditis with extensive pericardial calcification

- Will see rim (light segment), which is the pericardium filled with calcium

- "Thick bright rim of calcified pericardium"


What is seen here?

Chest CT form pt with pericardial constriction showing thickened pericardium (arrows) and a left pleural effusion(*)


Pathophysiology of constrictive pericarditis?

- Impaired diastolic filling (due to thickening of pericardium)

- Elevation of LV diastolic pressure

- Elevation of atrial pressure

- Equalization of elevated IC pressure

(These are also characteristics of cardicac tamponade)


What are the PE findings in constrictive pericarditis?

- Present with CHF signs: dependent edema, hepatomegaly, ascites, and JVD

- JVP: elevated with steep y-descent

- Small quiet heart and clear lungs

- Kussmaul sign

- Pericardial knock extra sound


What is Kussmaul sign?

- More prominent neck veins during inspiration

- Distended neck veins that do NOT collapse with inspiration 


What is a pericardial knock?

- Early diastolic extra sound (K)

- Occurs shortly after S2

- Results from abrupt cessation or slowing of ventricular filling as the stiff pericardium limits expansion of the ventricle

- May be confused with an S3 gallop


How is constrictive pericarditis diagnosed?

Right heart catheterization with dip-and-plateau RV pressure


What causes a steep y descent (JVP) and dip-and-plateau (RVP) in constrictive pericarditis?

Why NOT in cardiac tamponade?

In constrictive pericarditis, enhanced early RV filling leads to:

- Rapid RA emptying >> steep Y descent

- Rapid RV filling >> "dip" in RVP

Cardiac tamponade is a pan-diastolic impairment of RV/LV filling; NO enhanced early filling

- NO early diastolic steep descent (in fact, y-descent is blunted)

- NO early diastolic "dip" in RVP


What characteristics are responsible for the dip-and-plateau RVP in constrictive pericarditis?

- Enhanced early RV filling -> "dip"

- Reduced late RV filling -> "plateau"


What is the clincial triad of constrictive pericarditis?

1. Congestive heart failure signs and symptoms

2. Prominent Y descent in the neck veins

3. Small quiet heart


Compare and contrast cardiac tamponade and constrictive pericarditis

- Filling

- Heart sounds

- Observed in JVP/cath


What is the treatment for cardiac tamponade?

Pericardiocentesis- pericardial tap to remove pericardial fluid; may insert drain

- Considered a medical emergency (person about to go into shot)


What is the treatment for constrictive pericarditis?

Pericardiectomy- surgical resection of the thickened pericardium


Key points of pericardial diseases:

- What is the major determinant of cardiac tamponade?

Rate of rise in pericardial pressure (NOT AMOUNT of fluid)

- Determines how much pericardium can accommodate the fluid


Is pulsus paradoxus a hallmark of cardiac tamponade or constrictive pericarditis?

Pericardial tamponade


Is a pericardial knock a hallmark of cardiac tamponade or constrictive pericarditis?

Constrictive pericarditis