What are some congenital pericardial diseases?
Absence of pericardium, PPDH
What are some acquired pericardial diseases?
Pericardial eff and cardiac tamponade, constrictive pericarditis
What are the 2 layers of the pericardium?
Fibrous and serous (parietal and visceral)
What are the 3 types of effusions and which is most common?
Hemorrhagic (most common), transudate, exudate
What are some DDx for hemorrhagic pericardial eff?
Neoplasia (HSA, chemodectoma, mesothelioma, ectopic thyroid CA, LSA), idiopathic
What are some DDx for transudate pericardial eff?
R-CHF, hypoAlb, chemodectoma, infections/toxemia, pericardial cysts, PPDH
What are some DDx for exudative pericardial eff?
Infectious (FB/hardware diz in cattle, fungal, bacterial, viral), sterile
What are the most common spp to have pericardial effusion?
Dogs and cattle
Pericardial effusion is a _____ dysfunction disease.
What is cardiac tamponade?
Clinical syndrome that occurs when increased intrapericardial pressure interferes with normal cardiac filling
What is the pathophysiology of cardiac tamponade?
- Underlying disease causes pericardial effusion
- Increased pressure in pericardial space compresses the heart chambers (R > L)
- Reduced cardiac filling --> low CO and low BP
- Compensation over time --> sudden death
OR just #3 --> sudden death
When does sudden death due to cardiac tamponade occur?
If the CO is severely and/or acutely compromised
How does compensation work in cardiac tamponade?
Over time activation of RAAS results in fluid retention and vasoconstriction, stabilizing the BP
What is the appearance of the heart on rads when there is pericadial effusion?
Cardiac tamponade can occur with low volume effusions if they occur _____.
Why does slowly developing pericardial effusion have less consequences over time?
The pericardium has time to stretch and the heart can compensate
What are some CS of cardiac tamponade?
Collapse, weakness, decreased appetite, vomiting, lethargy, decreased milk production (cattle), polyurea, polydypsia
PE findings in cardiac tamponade are directly linked to the _____.
What are PE findings with cardiac tamponade?
Muffled heart sounds, weak pulses (pulsus paradoxus), jugular distention, signs of R-HF
What is pulsus paradoxus?
Pericardial effusion --> RV free wall can't stretch --> IVS must stretch further --> decreased LV size --> less LV filling during inspiration --> less blood pumped out to body --> weak femoral pulses during inspiration
What are the 3 hallmark findings of pericardial effusion on rads?
- Enlarged, rounded cardiac silhouette
- Dilated CdVC
- Small pulmonary arteries and veins
What are "other" findings that can show with pericardial effusion?
Sharp, well-demarcated edges of cardiac silhouette (less motion artifact), no distinct chamber enlargement, mass effect or lung metastasis, pleural effusion (R-HF), metallic FB (cattle)
What ECG abnormalities may be observed in pericardial effusion?
Decreased QRS amplitude (< 1 mV), electrical alternans (heart "swings" in the fluid)
What is electrical alternans?
ECG finding where the R waves are of variable heights due to large effusions where the heart "swings" in the fluid
What does pericardial effusion look like on echo?
Anechoic (black) fluid between pericardium and heart (mixed echogenicity if exufate or new blood)
What finding can cardiac tamponade cause on echo?
Compression/collapse of RA +/- RV
What is the treatment for pericardial effusion if the patient is unstable / low BP?
IVF while preparing for a pericardiocentesis (shock bolus of crystalloids), reassess BP, repeat until ready
What are potential complications of a pericardiocentesis?
Infection, arrhythmias, hemorrhage, pneumothorax, cardiocentesis
How can infection be avoided in a pericardiocentesis?
How can arrhythmias be noted during a pericardiocentesis?