Pericardial Diseases Flashcards
What are the two parts of the pericardium?
- Parietal pericardium
- Visceral pericardium
What is the true pericardium?
- Parietal pericardium
What must occur for cardiac tamponade to occur?
- Pressure from pericardium is normally 0
- When pericardial pressure exceeds the pressure of the right atrium, tamponade can occur
- Pericardial pressure must exceed 5
When do you start to get clinical signs with pericardial effusion?
- When you have cardiac tamponade
What would clinical signs be with pericardial effusion?
- Heart sounds muffled, but lung sounds are fine
- Precordium can be absent or shifted
What would clinical signs be with cardiac tamponade?
- Collapsed
- Sedated
- Exercise intolerant
- Jugular distension or pulsation and possible ascites
- Often animals are tachycardic because they can’t get enough blood into their heart
- Pulsus paradoxus
Pulsus paradoxus definition
- When the animal inspires, the pulses are weaker; when you expire they are stronger
Pathophysiology of pulsus paradoxus
- In a normal individual, when your chest gets wider, your pleural pressures drop
- Negative pressure pulls your pericardium and right heart wider
- Improved right ventricular filling and decreased left heart filling because the interventricular septum is shared
Historical findings of animals with pericardial effusion?
- Collapse/syncope
- Weakness/depression/exercise intolerance
- Tachypnea
- Right sided abdominal enlargement
Radiographic findings of pericardial effusion
- Enlargement of the cardiac silhouette (+/- globoid)
- Sharp, well demarcated edges of the heart
- Distension of the caudal vena cava (as right atrium is getting squashed)
- Small pulmonary vessels** (lungs are not receiving as much blood)
- Mass effects (mediastinal deviation of the trachea)
- Abdominal effusion
Three radiographic hallmarks of pericardial effusion**
- Enlarged cardiac silhouette (globoid or subtle)
- Small pulmonary vasculature
- Distension of the caudal vena cava
ECG findings for pericardial effusion
- Decreased QRS amplitude (often <1 mV)
- Electrical alternans (short and tall Q wave)
- Other - VPCs, supraventricular tachycardia due to irritation of the myocardium
Echocardiogram findings of pericardial effusion
- Ultrasound shows a distinction between cardiac enlargement and pericardial effusion
- Right atrium may be compressed if you have cardiac tamponade
Emergency treatment for pericardial effusion short term goal
- Increase preload to force blood into the heart
What is the emergency short term treatment for pericardial effusion?
- IV catheter - rapid IV fluid administration
- Crystalloids
- Start with a quarter shock bolus while you prepare to tap (90 mL/kg * 4 = 20mL/kg IV bolus OR trick is to take weight in lbs and add a zero)
- E.g. give a 60 lb dog 600 mLs
- NO DIURETICS!!!
Long term goal of pericardial effusion therapy
- Relieve tamponade and determine etiology
What are the two purposes of pericardiocentesis?
- Diagnostic and therapeutic
What samples do you collect for pericardiocentesis?
- Cytology and culture
- Purple and red top
What are the three primary types of fluid you could get back from a cytology?
- Exudates
- Transudates
- Hemorrhage
What are some dfdx for transudates?
- Hernias
- Cysts
- CHF
- Hypoproteinemia
- Heart basedmass (chemodectoma)
DfDx for exudates?
- Foreign body (e.g. grass awn, quills)
- Nocardia
- Fungal
- FIP in cats
- Idiopathic inflammation
Dfdx for hemorrhagic effusion?
- Neoplasia (#1 hemangiosarcoma, #2 chemodectoma, #3 way down ectopic thyroid carcinoma, lymphosarcoma)
- Coagulopathy (retroperitoneal bleeding, peritoneal bleeding)
- Idiopathic (Golden Retrievers might be more predisposed)
Cytology for pericardial fluid analysis - are many of them diagnostic?
- No, less than 8% of cytologies were diagnostic
- Only really send it off if you think it will be exudative or if it looks strange
What is the #1 differential for a case of hemorrhagic pericardial effusion?
- Hemangiosarcoma
Where is the most common location for a hemangiosarcoma in the heart?
Right auricular tip
Where do chemodectomas tend to hang out in the heart?
- Base of the heart at the aortic base
What are the major risks of pericardiocentesis?
- VPCs
- Location of the coronary artery (these are on the left side)
- Lung laceration and resultant pneumothorax, hemorrhage
- Dissemination of infection/neoplastic cells to the pleural space
- Chance of bleeding out post-centesis
- Bottom line: TAMPONADE WILL KILL THEM FIRST!
Pericardiocentesis supplies essentials
- Large gauge catheter
- Extension set
- 3 way stop cock
- Syringe
- Shave and do a sterile prep
Other supplies
- Clippers
- Sterile scrub
- Sterile gloves
- Tapping kit: Scalpel blade, 14 or 16 gauge needle (consider long large gauge peripheral catheter for smaller patients), two red top tubes, 1 purple top tube, 60 mL syringe, 3 way stop cock, 2 IV extension sets
- 2 mg/kg dose of lidocaine
- ECG machine
- Extra hands: holder, tapper, aspirator
- +/- ultrasound
- +/- sedation (2 mg/kg Butorphanol IV)
- /- local block
What tubes do you need for a pericardiocentesis?
- 1 lavender top tube
- 2 red top tubes
How do you position a patient for pericardiocentesis?
- If you have an echo table, put in right lateral recumbency to be able to access the patient’s ride side
- Sternal recumbency too
- Want the right sided cranioventral thorax to be accessible
Where do you clip for a pericardiocentesis?
- Clip right ventral thorax at the intercostal space 3 to 6 (where elbow touches the chest)
How to prep the area for pericardiocentesis?
- Surgical scrub of the shaved area
What should you be monitoring during the pericardiocentesis?
- ECG leads!
- Monitor for VPCs throughout procedure
What is your mnemonic for where to tap?
- “Go right ahead and tap”
- On the right and ahead of the rib
Where do you insert the catheter relative to the rib?
- Insert catheter cranial to the rib to avoid the intercostal arteries that are caudal to the rib
Method for the actual tapping
- Go cranial to the rib
- Go perpendicular to the body wall
- Slowly advance the catheter until you are able to aspirate fluid
- If you go too far and see VPCs, then back the catheter out
What should you be doing with the two red top tubes and one lavender top tube?
- Monitor one red top tube for clotting
- Monitor red top and purple top for cytology and culture
What does it mean if your red top tube clots?
- That you are in the heart
- Hemorrhagic effusion does not clot
What should effusion PCV be compared to peripheral PCV?
- Should be lower than peripheral PCV
What should you see happen to the heart rate as pericardial effusion resolves?
- Improved heart rate as cardiac filling and output resolves
- QRS should get taller (better contraction) and tachycardia should resolve
What should you monitor post-pericardiocentesis?
- Heart rate, blood pressure, respiratory rate, PCV/TS
- Tamponade and hemorrhage
- Want to make sure they don’t re-effuse quickly
- Ensure free access to water
With a coagulopathy and hemorrhagic effusion, should you remove the blood?
- Ideally want to try and manage with IVF
- If they are in tamponade, you need to remove the fluid
Treatment and prognosis for HSA
- +/- chemotherapy
- 6-12 weeks
Treatment and prognosis for chemodectoma
- Ectomy or window
- 1-3 years
Treatment and prognosis for mesothelioma
- Pericardectomy
- 12-20 weeks
Treatment and prognosis for CHF
- Tx underlying
- depends
Treatment and prognosis for hypoalbuminemia
- Tx underlying and depends
Treatment and prognosis for vasculopathy
- Tx underlying and depends
Treatment and prognosis for infectious disease (bacterial, fungal, FIP)
- Drain/flush
- +/- pericardectomy
- Fair to poor prognosis
Treatment and prognosis for idiopathic (due to viral or immune mediated)
- Centesis, steroids
- Window
- Good prognosis
What is it called when there is retention of abdominal contents in the pericardium?
- Peritoneal-pericardial diaphragmatic hernia
What causes a peritoneal-pericardial diaphragmatic hernia?
- Failure of embryologic separation
Signalment of PPDH
- Usually young
- No trauma history
- Most common in cats
- I guess Weimeraners are predisposed too
Clinical signs of PPDH
- Variable; respiratory or GI
Physical exam findings of PPDH
- Muffled heart sounds
- No ascites, etc.
Diagnosis of PPDH
- Radiographs, ultrasound
Treatment for PPDH
- If asymptomatic, leave them alone
What is the most common organ that goes into the pericardium?
- Omentum!
Which is more common in cats: PPDH or pericardial effusion?
- PPDH
What do radiographs look like with PPDH in ca at?
- Diaphragm and heart base will be touching (not common in cats)
- May see intestines or gas within the heart
- Very wide base enlargement
- Pericardial silhouette will be less crisp
Prognosis for PPDH if no clinical signs and treatment
- No surgery
- Typically good prognosis if no clinical signs
PPDH prognosis if clinical signs are present
- Variable
- May need surgery
