Chapter 107 Pericardial Surgery Flashcards
What are the two layers of the pericardium called?
Outer fibrous, inner serous (serous layer forms parietal and visceral layer (visceral layer = epicardium)
What is the name of the ventral attachment of the pericardium to the muscular insertion of the diaphragm?
Sternopericardiac ligament
What is normal intrapericardial pressure?
Zero (or negative)
What is normal pericardial volume?
1 - 15ml
Briefly outline the pathophysiology in increased central venous and portal pressure in cases of tamponade
- Tamponade –> reduced cardiac output and increased systemic venous pressure.
- RAAS activated –> Sodium and water retention
- Sympathetic stimulation –> positive inotropic and chonotropic effects + vasoconstriction.
- Right atrium not stretched therefore no ANP to counteract
Increased systemic venous and portal pressures.
Explain the pathophysiology behind pulsus paradoxus
How great is variation typically?
- Increased venous return to R side during inspiration (pericardial and RV pressures decrease) –> pulmonary blood flow.
- However total heart volume limited by pericardial effusion so as Rv fills, septum shifts to left –> reduced L end-diastolic volume and output i.e. decreased arterial pressure.
>10mmHg variation typically.
What is the usual histological diagnosis for pericardial cysts?
cystic haematoma
?assoc with PPDH
What is the usual clinical presentation of pericardial rupture?
Asymptomatic initially but may stricture –> vanae cavae compression
What radiographic findings may be associated with strictured pericardial rupture
Caudal vena cava may appear kinked cranial to diaphragm
Angiogram of a dog with pericardial rupture. The caudal vena cava is kinked (white arrow) between the diaphragm and the right atrium. The pericardium is compressing the caudal vena cava (black arrow).
How is strictured pricardium following rupture best diagnosed?
How is it treated?
Caval angiography
R 5th or 6th ICT + cut fibrous band (+- patch angioplasty of cava if cava wall is strictured).
List 4 broad differentials for transudative pericardial effusion
- CHF
- PPDH
- Hypoalbuminaemia
- Increased vascular permeability
How are exudative pericardial effusions classified?
Infectious vs non-infectious pericarditis
e.g.
Infectious
- FIP
- Fungal/viral
Non-infectious
- Feline cardiomyopathy
List 5 differentials for haemorrhagic pericardial effusion
- Idiopathic
- Neoplasia
- L atrial rupture (secondary to MMVD - suspect if pericardial effusion and left apical systolic murmur))
- Coagulation abnormalities
- Trauma
What is the most common cause of haemorrhagic pericardial effusion?
Idiopathic
What is the most and second most common tumour causing haemorrhagic pericardial effusion?
- Haemangiosarcoma
- Chemodectoma
What is this ECG trace example of?
Electrical alternans
Due to swinging of beatin gheart within pericardial sac.
What is the sens/spec of echo for detection of cardiac masses in dogs with pericardial effusion?
82% sensitivity, 100% specificity
Aside from echo, what other test was 100% specific (and 82% sensitive) for detection of cardiac haemagiosarcomas?
[cardiac troponin 1] > 0.25 ng/ml
What is the difference between total and subtotal pericardiectomy?
Total = whole pericardium (phrenic nerves peeled off).
Sub-total = ventral to phrenic nerves.
List 3 approaches for subtotal pericardiectomy
- MS
- R ICT
- transabdominal, transdiaphragmatic
- (thoracoscopic –> pericardial window)
What is the rough size recommendation for pericardial window in large dog (to prevent herniation)
3x3cm
What was the MST of dogs with aortic body tumours (?with pericardial effusion) without vs with pericardiectomy?
42d vs 730d
List a ‘non-surgical’ technique for creating pericardial window
Percutaneous balloon pericardiotomy
What is the MST from onset of pericardial effusion in dogs with mesothelioma?
1 year
