Pericarditis
Pericarditis is the inflammation of the pericardial layers around the heart.
Most cases of are idiopathic (w/o an underlying cause). Underlying causes of it include:
Infection
Post-MI - Can occur as acute pericarditis or Dressler's syndrome after a myocardial infarction
Acute - 1-3 days after an MI due to the healing necrotic heart tissue interacting with the pericardium
Dressler syndrome - Weeks to months after an MI as an autoimmune response, triggering systemic inflammation (affects other serous membranes like the pleura = pleurisy)
Cancer
Autoimmune e.g. RA, SLE etc.
Drug-induced e.g. Methotrexate, Hydralazine
Uraemia – seen in ESRF (end-stage renal failure
Presentation
It's main presenting symptom is Pleuritic chest pain (>90%), which is:
Retrosternal
Radiates to the ridge of the trapezius
Relieved by sitting forwards
Patients may also present with fever and dyspnoea.
O/E - The signs that may be found include:
Pericardial rub – Due to friction between layers, typically loudest at the left lower sternal border, best heard on leaning forward
Signs of effusion
Beck’s Triad if cardiac tamponade
Investigations
ECG changes - Widespread saddle-shaped ST elevation, PR depression, Small QRS
Over the next 8 weeks, the ST normalises first, followed by the T waves flattening, then inverting, before normalising
Other investigations to do include:
Basic obs – Checking for signs of haemodynamic compromise
Bloods - FBC (WCC, CRP), U&Es, LFTs, Troponin
Echo
Management
Idiopathic and Viral pericarditis:
1st line is Exercise restriction, NSAIDs e.g. Ibuprofen and Colchicine
Aspirin is favoured instead if the patient also needs antiplatelet therapy.
Patient's should be co-prescribed a PPI
Colchicine should be used with caution in those with renal/hepatic impairment
2nd line is with Steroids
N.B. Exercise restriction is recommended due to the risk of progression to myocarditis.
Bacterial pericarditis:
1st line is IV Abx, and pericardiocentesis if purulent exudate is present
Pericardectomy is done if adhesions form or recurrent tamponade occurs
Constrictive Pericarditis
This is where the inflammation causes fibrosis and calcification, with adhesions forming between the pericardial layers. The pericardium can become stiff and inelastic to a point where it hinders diastolic filling (+ CO) = Constrictive Pericarditis. Highest risk of this is with bacterial pericarditis.
The changes that occur here are chronic, therefore the body is able to compensate. Patients may present with symptoms of fluid overload, and poor exercise tolerance/SOBOE. The definitive treatment here is a surgical pericardectomy.