Introduction
- There is a potential space between the myocardium and the pericardium (the pericardial sac).
- This may become distended with fluid.
- Pressure within the pericardial sac compromizes cardiac function ( cardiac tamponade - particularly by causing collapse of the thinner-walled right ventricle).
- Cardiac tamponade → acute congestive heart failure
.
Uses
- Drainage of pericardial fluid:
- Hemorrhage (warfarin).
- FIP .
- Pericardial/heart base tumor → transudation.
- Septic pericarditis.
- Heart disease (valvular malformational and hypertrophic cardiomyopathy - primary or secondary)
Advantages
- Minimally invasive procedure when correctly performed.
- Produces rapid benefit to patient.
Disadvantages
- Risk of lacerating myocardium or coronary arteries.
- May be unable to drain all fluid from pericardial sac.
- Risk of recurrence of fluid accumulation.
Requirements
Materials required
Minimum equipment
- Radiographic facilities.
Ideal equipment
- Ultrasound machine .
Visualization of correct positioning of catheter is very reassuring to inexperienced operator. - ECG machine can be useful for monitoring arrhythmias before and after procedure.
Observation of the ECG trace during catheter placement is often disturbing; even in cases where catheter is correctly positioned.
Minimum consumables
- 3 cm intravenous catheter (20-22 gauge)
- Three way tap.
- Large syringe (12 ml).
Preparation
- Radiography and preferably ultrasonography should be performed to confirm pericardial fluid.
- 10 minutes to sedate animal and prepare site on chest wall.
Sedation needs great care as there is a major risk of collapse.
Sequelae
Complications
- Recurrence of pericardial effusion is common in cases of idiopathic pericardial effusion.
- With each recurrence the pericardial sac becomes more thickened and clinical signs develop with the presence of less pericardial fluid.
- Repeated pericardial drainages become more difficult with time.
Prognosis
- Guarded/poor prognosis for septic pericarditis and neoplasia.
- Poor prognosis for drainage of FIP related effusions.
Reasons for treatment failure
- Inability to drain all effusion.
Sources
Publications
- Rush J E, Keene B W, Fox P R (1990) Pericardial disease in the cat, a retrospective evaluation of 66 cases. JAAHA 26 p39.
