Sa Medicine Ii -- Pericardial Disease

Front 1

What is the anatomy of the pericardium?

Back 1

Parietal pericardium

--fibrous, acellular

--composed of collagen fibers

--ligamentous attachments anchor the heart

Visceral pericardium

--serous pericardium

--adhered to surface of heart

Front 2

Pericardial fluid composition?

Back 2

--phospholipid-rich

--lubricates pericardial sac

--low protein, few cells

Front 3

Function of pericardium?

Back 3

--lubrication

--barrier to infection

--maintains position of the heart

--innervated with mechanoreceptors, chemoreceptors, afferent input, etc.

--restrainig effect on cardiac volume

--contributes to diastolic interaction

Front 4

How does the pericardium have a restraining effect on cardiac volume?

Back 4

--elastic at low stress

--tissue becomes stiff at high stretch

Front 5

What is the most common congenital disorder of the pericardium? Due to?

Back 5

--peritoneopericardial diaphragmatic hernia (PPDH)

--due to abnormal development of the diaphragm

Front 6

When is PPDH repair indicated?

Back 6

--clinical signs

--GI obstruction

--impaired hepatic/splenic blood supply

Front 7

Diagnosis of PPDH?

Back 7

--radiographic contrast study

Front 8

Less common congenital disorders?

Back 8

--absence of the pericardium (usually incidental)

>> herniation may occur with partial defect

--intrapericardial cysts

>> commonly present with cardiac tamponade

Front 9

What is constrictive pericarditis? Results in?

Back 9

--acquired dz where pericardium becomes stiff and fibrotic

>> restricted filling

>> signs of right-sided CHF

Front 10

Constrictive pericarditis may occur secondary to?

Back 10

-- may occur secondary to any cause of chronic pericarditis

>> Coccidioides immitis

>> neoplasia

>> FB

>> recurrent idiopathic PE

>> septic peritonitis

Front 11

Diagnosis of constrictive pericarditis?

Back 11

--cardiac catheterization

>> measure cardiac pressures

--echocardiography

>> look for myocardial disease, effusion

>> may suggest pericardial constriction

Front 12

Treatment of constrictive pericarditis?

Back 12

--surgical pericardiectomy

>> removal of parietal pericardium

+/- epicardial stripping

--treatment of underlying disease

Front 13

What is the most common cause of pericardial disease?

Back 13

--pericardial effusion

Front 14

Causes of pericardial effusion in dogs?

Back 14

--neoplasia

>> hemangiosarcoma (GSD, goldens, lg. breeds)

>> heart base tumors (brachycephalics)

>> mesothelioma

>> lymphoma

--idiopathic

Front 15

Two types of heart base tumors in dogs?

Back 15

--chemodectoma

--ectopic thyroid tumor

Front 16

Less common causes of pericardial effusion in dogs?

Back 16

--LA tear (often fatal)

--coagulopathy

--FB

--CHF

--infection

Front 17

Causes of pericardial effusion in cats?

Back 17

--congestive heart failure (L or R)

--neoplasia (lymphoma)

--feline infectious peritonitis

Front 18

What is the relationship between pericardial effusion volume and intrapericardial pressure?

Back 18

--inc. intrapericardial pressure w/ inc. volume

--inc. ventricular diastolic pressure

--impaired filling

--dec. CO due to low stroke volume

--fall in blood pressure

>> rapidly approach cardiac tamponade

Front 19

Compensation for pericardial effusion?

Back 19

--expansion of pericardial sac (chronic)

--activation of RAAS

>> fluid retention

>> inc. HR

--absence of ANP secretion

>> not promoting natriuresis

Front 20

Clinical signs of pericardial effusion on physical exam?

Back 20

--muffled heart sounds

--jugular venous distension

--weak femoral pulses

--RHF with chronic effusions

+/- pulsus paradoxus

+/- ascites

+/- pleural effusion

Front 21

What is pulses paradoxus? Cause?

Back 21

-- beats can be ausculted but are not felt on femoral a.

--inc. venous return to right heart on inspiration >> interventricular septum is displaced toward LV due to high intrapericardial pressure >> dec. LV SV >> drop in BP

Front 22

Diagnosis of pericardial effusion on ECG?

Back 22

--low amplitude QRS

-- +/- electrical alternans

-- sinus tachycardia

-- other arrhythmias (VPCs, etc)

Front 23

Diagnosis of pericardial effusion on rads?

Back 23

--globoid cardiac silhouette (lg. vol fluid)

--enlarged vena cava

-- +/- mass effect, pulmonary metastasis

Front 24

Diagnosis of pericardial effusion on ultrasound?

Important to look for?

Back 24

--detection of intrapericardial fluid

--evaluate for underlying heart disease

-- ID tumor, if present

>> more sensitive in the presence of effusion

Front 25

Where does hemangiosarcoma hang out?

Back 25

--right auricle or right atrium

Front 26

What causes cardiac tamponade? Emergency treatment, even prior to pericardiocentesis?

Back 26

-- intrapericardial pressure > intracardiac pressure

>> heart can no longer fill

>> limit of pericardial stretch exceeded

-- fluid bolus to inc. filling pressure

Front 27

Pericardiocentesis preparation?

Back 27

-- start fluid bolus >> inc. intravascular vol.

-- clip and prep right side of thorax

-- attach ECG leads

-- make a lidocaine bleb

-- nick skin over bleb

-- prepare over-the needle catheter (14 -16 ga)

>> fenestrate to prevent occlusion

Front 28

Pericardiocentesis procedure?

Back 28

--advance catheter and stylet into pericardial space using sterile technique

--remove stylet, attach catheter to extension line/syringe

--draw off fluid (usually hemorrhagic)

--monitor ECG for arrhythmias

Front 29

What should you do once you have drawn off some pericardial fluid?

Back 29

--put in red top tube, monitor for clotting

Front 30

If you have successfully performed pericardiocentesis, what should happen?

Back 30

-- HR should slow

--no clots should form in red top tube

--pulse quality should improve

Front 31

Pericardial fluid analysis?

Back 31

-- overall diagnostic yield low (7.7%)

-- high diagnostic yield if HCT < 10% (20.3%)

-- often diagnostic in cases of inf. or lymphoma

Front 32

If there are no signs of neoplasia on pericardial fluid analysis?

Back 32

--does not rule out neoplasia

Front 33

Additional diagnostic tests for pericardial effusion?

Back 33

--abdominal ultrasound

--advanced imaging of thorax/abdomen

--thoracotomy/thoracoscopy sx

>> thorax explore and pericardiectomy

>> histopath for pericardium/mass

--bloodwork

Front 34

Bloodwork for pericardial effusion?

Back 34

--CBC, chemistry, UA

--T4 (suspect ectopic thyroid tumor)

--elevated cTnl may suggest hemangiosarcoma

>> cardiac troponin

Front 35

Long term treatment?

Back 35

--repeat pericardiocentesis

>> prevent tamonade

--pericardiectomy (idiopathic)

>> esp. with recurrent PE with heart base mass

--treatment for neoplasia

Front 36

Treatment for neoplasia causing pericardial effusion?

Back 36

--pericardiectomy

--radiation therapy (heart base tumors)

--radioactive iodine (ectopic thyroid tumors)

--chemotherapy (hemangiosarcoma)

>> +/- auriculectomy
>> +/- radiation

Front 37

Prognosis of pericardial effusion?

Back 37

--idiopathic: long term survival (up to 3 y) reported

>> most require repeat pericardiocentesis or pericardectomy

--LA tear: usually fatal the first time it happens

>> predisposed to reoccur if they survive first time

Front 38

Dogs with idiopathic pericardial effusion may actually have?

Back 38

--mesothelioma

Front 39

Prognosis of pericardial effusion due to neoplasia?

Back 39

--heart base mass: fair prognosis w/o surgery, good prognosis with pericardiectomy (~2y MST)

--hemangiosarcoma: grave prognosis, 164 MST with surgery and chemo

--mesothelioma: unknown

Front 40

Common neoplasms that cause pericardial effusion in cats?

Back 40

-- lymphoma