CASE REPORT
A 60-year-old male with background of atrial fibrillation, hypertension
and chronic obstructive pulmonary disease was admitted to his local
hospital with acutely worsening shortness of breath. Patient consent was
obtained for this report. Ethical approval was waived. Data sharing is
not applicable to this article as no new data were created or analyzed
in this study. Computed tomography (CT) chest showed a mass in the right
side of the pericardium. (Figure 1) The patient was discussed by both
cardiology and respiratory multidisciplinary teams (MDT); it was decided
to urgently transfer to a tertiary cardiac centre for further assessment
including positron emission tomography (PET) scan to exclude metastasis
from suspected pericardial tumour and consideration of surgery.
Following transfer, the patient experienced significantly worsening
shortness of breath and was also unable to undergo PET scan due to
significant symptoms of SVC obstruction and tamponade. Therefore,
decision was made to proceed to emergency surgery. Under general
anaesthetic, via median sternotomy the pericardium was opened. A mass
was found in right atrial wall invading intra-atrial groove and
extending over SVC. Following institution of cardiopulmonary bypass the
tumour was removed en bloc with the right atrial free wall and dissected
from the interatrial septum. The atrium was reconstructed with bovine
pericardial patch. The patient was weaned easily from bypass and closed
in the usual fashion.
Histology showed a fatty tumour weighing 120g, extensive replacement of
myocardium with a vascularised lipomatous tumour composed of lobules and
less well defined files of mature adipocytes admixed with variable
proportions of multivacuolated brown fat cells and areas of bland
spindle cells. The conclusion is that the tumour was a hibernoma with no
evidence of malignancy.
Post-operatively, the patient was transferred to intensive therapy unit
(ITU) and initially made a good recovery. On the fourth post-operative
day, he developed type 1 respiratory failure requiring nasal high flow
oxygen therapy. Despite four anti-arrhythmic agents, the patient
continued to experience intermittent atrial fibrillation with fast heart
rate and therefore underwent direct current cardioversion (DCCV), which
was successful. He was subsequently stepped down to the ward and
discharged home. At four months follow up, the patient was doing well.
Repeat echocardiogram and CT showed dilated right atrium, but no
occupying mass. LV ejection fraction was 55-60% and RV function were
normal.