CASE PRESENTATION
This is a case of a 66-year-old
man with a previous history of hypertension, diabetes, chronic kidney
disease, and psoriasis. He presented to the communicable disease center
(CDC) with a three-day history of fever, cough, and shortness of breath.
On admission, his vital signs were as follows: blood
pressure:115/52mmHg, heart rate: 75 b/min, respiratory rate: 20 b/min,
and oxygen saturation (O2sat): 93% on room air. His
body mass index (BMI) was 29 kg/m2. Physical
examination was remarkable for bilateral chest crackles with normal
cardiovascular examination.
His electrocardiogram (ECG) revealed a sinus rhythm with right bundle
branch block (RBBB) and left axis deviation. Chest x-ray showed patchy
peripheral ground-glass opacities in both lungs and soft consolidations
in the right middle lobe. Polymerase chain reaction (PCR) was performed
on a nasopharyngeal swab and returned positive for SARS-CoV‑2. In
addition, blood tests showed WBC of 5.9 x10^3/uL, hemoglobin of 10
gm/dL(N{13-17 gm/dL}), C‑reactive protein (CRP) of 146 mg/L [N
< 6 mg/L]), ferritin of 2619 ug/L [N < 553
ug/L]), creatinine of 190 umol/L (N{62-106 umol/L), and D Dimer of
2.3 mg/L FEU [N < 0.5 mg/L FEU]).
He was started on oxygen therapy at 2 liters per minute via nasal
cannula, but shortly after admission, he became severely hypoxic, and
then, he was transferred to the medical intensive care unit (MICU) and
kept on continuous positive airway pressure (CPAP) to maintain oxygen
saturation of 95%.
Transthoracic echocardiography (TTE) was performed, which revealed
normal biventricular size and function with no significant valvular
disease. Mild pulmonary hypertension with an estimated systolic
pulmonary artery pressure of 48mmHg was noted. The study showed echo
dense mass located on the right atrial (RA) roof, best seen in
four-chamber view. There was another echo-lucent mass in the RA and
protruding into the tricuspid valve annulus, best seen in the RV inflow
view, as shown in (Figure 1). A prior TTE report that had been performed
in another center one month ago revealed no interatrial mass.
Because of acute COVID-19 pneumonia and elevated D-dimer, the RA mass
was considered and treated as a thrombus. He was started on a
therapeutic dose of intravenous heparin and warfarin; thus, the INR was
maintained in the therapeutic range between 2 to 3. Repeated echo did
not show any significant differences. For a better assessment of the RA
mass, Transesophageal echocardiography (TEE) was planned, but was not
performed due to acute respiratory distress with low oxygen saturation.
Instead, 12 days later, upon clinical recovery a cardiac magnetic
resonance imaging (CMR) was performed.
The images were obtained on a 1.5 Tesla scanner (Philips Ingenia), and
findings from the multiple stacks of cine four-chamber views confirmed
the presence of a structure on the posterior wall of the RA that extends
onto the thickened interatrial septum (Figure 2). This smooth structure
moved during systole and diastole and was identified as crista
terminalis, which was rather prominent. T1 and T2 weighted images on the
axial plane of this structure had a similar signal intensity to the
subcutaneous fat revealing it as predominantly fatty deposition. T1
weighted images with fat saturation sequences (Figure 3) demonstrated
the suppression of fatty signals consistent with LHIAS of the thickened
interatrial septum associated with fatty deposition in the crista
terminalis. On post gadolinium, early and late acquisition, there were
no uptake or features to suggest the presence of thrombus or any other
cardiac tumors (Figure 4).
CMR concluded that the prominent RA mass was lipomatosis hypertrophy of
the interatrial septum, which extends to the crista terminalis with no
evidence of any thrombus. Hence the anticoagulation was discontinued,
and patient was discharged home in very good condition.