Pericardial dz + Cardiac Trauma - STOELTING CH 11 Flashcards
The pericardium is a _ sac covering the heart and a portion of the great vessels
fibroserous
2 layers of pericardium:
serosa (inner)
fibrosa (outer)
Serosa layer of pericardium contains 2 layers: a _ layer of epicardium and a _ layer.
visceral layer of epicardium and a parietal layer
-between these = pericardial cavity
Space between the visceral and parietal layer of the pericardium is called the _ _ and normally contains _ - _ mL of pericardial fluid (plasma ultrafiltrate)
pericardial cavity
10-50mL
Normal thickness of a pericardium is _ - _ mm
0.8-1.0mm
Pericardial reflections around the great vessels create sinuses. Where are they located?
-U-shaped oblique sinus
-transverse sinus
U shaped/oblique = behind LA, IVC, and pulm veins
Transverse = between aorta and PA, and the “dome” of LA and SVC
Lymph drainage of pericardial fluid occurs via: (4 lymph node sites)
-tracheal
-bronchial
-anterior mediastinal
-posterior mediastinal
What is the source of the viscoelastic mechanical properties of the pericardium?
dense parallel arrays of collagen layers with short elastin fibers between them
T/F Stiffness of pericardium is greater than that of the cardiac muscle
true
-allows equalization of ventricular compliances to maximize diastolic interaction
2 different resistances to mechanical stress found in pericardium, which types of stress affect which layers/fibers
-small effusions
-large effusions
small = impact only elastin fibers
large = opposed by the resistance of rigid collagen fibers
The pressure-volume curve of a pericardial effusion is _ -shaped
J
-either increases slowly/rapidly over time
-quick effusions reach limit of pericardial stretch despite less volume because less time to allow stretch to allow more volume
-slower effusions reach limit after more volume and time because compensatory mechanisms have more time to allow stretch
Describe the concept of ventricular interdependence.
Negative intrathoracic pressure during inspiration INCREASES RV filling. The interventricular septum accommodates this extra filling and SHIFTS LEFT, impairing LV filling. This causes a transient DECREASE in CO and systemic BP.
-this is exaggerated when intrapericardial pressures are elevated and cause pulsus paradoxus-seen in tamponade
Congenital partial pericardium absence is usually _ sided
left
Most common congenital pericardial disorder is _ _
pericardial cysts
Congenital pericardial cyst preferred treatment:
surgical excision via VATS
-high incidence of recurrence with only percutaneous drainage so surgical is best
Congenital pericardial cyst
-s/s
asymptomatic or respiratory dyspnea, arrhythmias, infection, compression of surrounding structures