Chest Pain Following Aortic Valve Replacement
A 69-year-old female presents with low grade fever and chest pain that worsens with inspiration and lying on her left side. One month prior, she had undergone aortic valve replacement (AVR) and aortic root enlargement with autologous pericardium via a mini-thoracotomy. At her initial presentation in the emergency department, a 12-lead ECG was obtained showing mild ST elevation more prominent in the lateral pre-cordial leads and diffuse PR depression (Figure 1). Her chest x-ray showed trace right sided pleural effusion and a chest computed tomography to rule out pulmonary embolus (PE) showed no evidence of PE but revealed a small anterior pericardial effusion (Figure 2). Laboratory evaluation was significant for mild elevation in her C-reactive protein (CRP = 19.1mg/dL) and erythrocyte sedimentation rate (ESR = 67mm/hr). A high-sensitivity troponin was negative. A presumptive diagnosis of acute pericarditis was made and the patient was discharged home on colchicine 0.6mg PO BID, ibuprofen 600mg PO TID and omeprazole.
Two months later she presented with ongoing shortness of breath and chest pain as well as new onset pedal edema. She was still taking colchicine and ibuprofen as prescribed. Her inflammatory markers at this time remained mildly elevated, with a CRP = 7.2mg/dL and ESR = 47mm/hr. An echocardiogram was performed which demonstrated significant flow variation of 67% across the tricuspid valve (Figure 3a), an increase in diastolic flow reversal in the hepatic vein during expiration (Figure 3c) and an abnormal septal bounce (Video 1, Figure 3d). Cardiac magnetic resonance imaging (MRI) was performed which demonstrated mild pericardial thickening, small anterior pericardial effusion, increased signal intensity of T2 short tau inversion recovery (T2-STIR) imaging and severe circumferential pericardial delayed enhancement on fat-saturated delayed enhancement imaging (Figure 4a-d). There was also evidence of flattening of the interventricular septum with inspiration (Video 2).
Which of the following is the next best step in management?