A Large Pericardial Mass
A 64-year-old gentleman with a 47 pack per year history presents to an outpatient cardiology clinic after a computed tomography (CT) scan of the chest (Figure 1) demonstrates a large mass in the mediastinum. The CT scan was performed by his family medicine physician for lung cancer screening given his age and smoking history. He has not had any symptoms to date. Specifically, he denies any dyspnea, cough, chest discomfort, fevers, weight loss, palpitations, or fatigue. He works full time as a building inspector and has not traveled outside of the country in the past 10 years. There is no history of prior surgeries. An exercise electrocardiography treadmill stress test taken a month prior was negative for ischemia.
Figure 1: Chest CT demonstrating a discrete, low-attenuation mediastinal lesion (white arrowhead) close to the right atrium and right paravertebral region measuring 12.2 x 8.0 cm in the maximum anterior-posterior and transverse dimensions, respectively.
On physical exam, his pulse is 77 beats per minute, blood pressure is 115/75 mmHg, and oxygen saturation is 98% on room air. Lungs are clear to auscultation bilaterally. Heart sounds are regular without any friction rub or murmur. Jugular venous pressure is within normal limits.
His transthoracic echocardiogram (Figure 2) shows an echolucent pericardial structure with normal biventricular size and function. T1- and T2-weighted cardiac magnetic resonance imaging (MRI) (Figure 3) confirms a large 12.1 cm x 8 cm pericardial mass located at the right cardiophrenic angle. There is no mass effect to the adjacent right atrium or inferior vena cava. No pericardial effusion and no evidence of hemodynamic compromise were found.
Figure 2: Transthoracic echocardiogram with echolucent space (white arrow) evident adjacent to the right atrium in the apical four chamber view corresponding to a pericardial mass.
Figure 3: Cardiac MRI with 12.1 x 8 cm, thin-walled, pericardial mass (white arrowhead) of the posterior right pericardium with the medial border abutting the inferior vena cava and right atrium.
Which of the following is the next best step in this patient?