Cardiac Tamponade Flashcards
What is cardiac tamponade?
- Accumulation of pericardial fluid, blood, pus or air within pericardial space
- Creates intra-pericardial pressure
- Restricts cardaic filling + reduces cardiac output
- A cardiac emergency + fatal if not quickly diagnosed/treated
- Diagnosis based upon clinical suspicion and supported by evidence of haemodynamic compromise on echo
DDx → constrictive pericarditis / restrictive cardiomyopathy / cardiogenic shock
What are the risk factors for cardiac tamponade?
- Malignancy → lung + breast
- Aortic dissection → Type A
- Purulent pericarditis → rare
- Large idiopathic pericardial effusion
- Iatrogenic related haemorrhage
- TB
Tamponade occurs at any age but most common in middle-aged + older people. In people from endemic regions, TB pericarditis remains prominent cause of effusion and tamponade.
In symptomatic patients, what are the most common causes of tamponade?
- Iatrogenic (post-cardiac surgery/intervention)
- Trauma
- Malignancy
- Idiopathic effusion
Others → viral infection, radiation-induced pericarditis, collagen vascular disease, myxoedema, TB
What are the clinical features of tamponade?
- Beck’s triad → hypotension / raised JVP* / muffled heart sounds
- Dyspnoea
- Chest pain (atypical, non-exertional)
- Abdo pain (2o hepatic congestion)
Other signs → tachycardia, pulsus paradoxus, electrical alternans (ECG)
*absent Y descent on JVP due to limited RV filling
What are the key differences between constrictive pericarditis and cardiac tamponade?
A pericardial effusion that raises intrapericardial pressure, reducing ventricular filling and thus dropping cardiac output can lead rapidly to cardiac arrest.
What is pulsus paradoxus and why does it occur?
Which investigations can be done for cardiac tamponade?
- ECG → electrical alternas
- FBC → inflammatory pericarditis / anaemia in CKD
- ESR → inflammatory marker
- Cardiac enzymes → cardiac trauma / MI
- CXR → ?enlarged cardiac silhouette
- Transthoracic Echo (best) → invesrsion of the free wall of right atrium for over 1/3rd of systole
With tamponade, there is a continuum of symptoms and haemodynamic effects. Pericardial effusions may resolve spontaneously or after treatment w/ NSAIDs or colchicine.
What is the management of a patient w/ haemodynamic instability?
Urgent pericardiocentesis