A Challenging Case of Recurrent Pericarditis
A 45-year-old otherwise healthy male presents to clinic for further management of recurrent pericarditis. Initial episode occurred 3.5 years ago when he presented with vague chest pressure that worsened with deep inspiration and supine positioning. Labs were notable for elevated white blood cell (WBC) 16.6K/mm3 with 81% neutrophils, C-reactive protein (CRP) 11.2 mg/dL (normal <0.9 mg/dL), and erythrocyte sedimentation rate (ESR) 39 mm/hr (normal <15 mm/hr). Troponin I, NT pro-BNP, and electrocardiogram were within normal limits. Computed tomography (CT) angiography of the chest was negative for pulmonary embolism. Transthoracic echocardiogram (TTE) showed normal ejection fraction and trivial pericardial effusion. Treadmill stress testing showed no ischemia. He was discharged on naproxen 500 mg as needed for presumed idiopathic pericarditis.
One month later, he was readmitted for 12 hours of worsening chest pain with dyspnea and found to have large circumferential pericardial effusion without tamponade. Repeat labs showed elevated WBC 13.8K/mm3, CRP 13.3 mg/dL, and ESR 90 mm/hr, with normal troponin I and negative rheumatologic workup, including antinuclear antibody (ANA), rheumatoid factor, anti-CCP, anti-Ro, and anti-La antibodies. Subxiphoid pericardial window was performed by cardiothoracic surgery with 500ml blood-tinged fluid, noting very thickened pericardium with epicardial inflammation. Surgical pathology reported benign fibromuscular and adipose tissue with mild perivascular chronic inflammation. He was started on colchicine 0.6 mg daily and naproxen 500 mg twice a day.
Two weeks post-discharge, during his first visit to pericardial clinic, labs showed persistently elevated ultrasensitive CRP (usCRP) 165.9 mg/L (normal <3.1 mg/L) and ESR 58 mm/hr. TTE (Figure 1) revealed trivial pericardial effusion, septal bounce, minimal respiratory variation of mitral valve inflows but significant variation in tricuspid inflow velocity, and some diastolic reversal seen in hepatic veins and superior vena cava.
Cardiac magnetic resonance imaging (MRI) (Figure 2) noted circumferential pericardial thickening, delayed enhancement, and increased intensity signal on T2 STIR imaging indicating inflammation, without features of constrictive physiology. Based on these findings, he was started on intensive triple therapy of colchicine 0.6 mg BID, ibuprofen 400 mg TID, and prednisone 40 mg daily, with clinical improvement and corresponding downtrend in inflammatory biomarkers (usCRP 1.5 mg/L, ESR 5 mm/hr) at his 4-month follow up. Concurrently, his cardiac MRI at that time also demonstrated substantial improvement in observed inflammation, with subtle diastolic septal bounce, so patient was slowly tapered off steroids, weaned by 5mg every 2 weeks.
One year after his first episode of pericarditis, patient unfortunately had a second flare, corroborated by usCRP 69 mg/L and ESR 30 mm/hr. He was continued on colchicine, but up-titrated from ibuprofen 400mg TID to 800 mg TID and reinitiated on prednisone 10 mg daily. Given recurrent steroid dependence, he was trialed on immunosuppression regimen with azathioprine 150 mg daily and subsequently successfully weaned off after 2 years due to improvement in clinical status and inflammatory biomarkers (usCRP 1.2 mg/L, ESR 2 mm/hr). However, 6 months after being off all meds, he again suffered from recurrence of symptoms, with usCRP 86.2 mg/L, ESR 109 mm/hr, and the following cardiac MRI (Figure 3).
What would be the most appropriate next step in management?