Discussion
We report our experience with a postero-inferior epicardial cyst which
was successfully resected with on-pump surgery. In our patient, excision
was complicated because the cyst was located in close proximity to
posterior descending artery. Resection of the cyst followed by
reinforcement of the thinned ventricular wall could not have been
accomplished without cardiopulmonary bypass support and the risk of
ventricular wall injury leading to complicated course couldnot be
completely ruled out. To circumvent such situation, we decided to
operate on CPB. CPB may be required when cysts compress surrounding
structures or erode the ventricular wall, coronaries (2, 3, and 7). We
suggest that surgeon must be aware of possible need for CPB in such
situations.
Preoperative differential diagnosis between a pericardial cyst and
epicardial cyst is challenging because they cannot be differentiated on
CT. (6) Although MRI is useful to differentiate cysts from other
mediastinal lesions, it cannot differentiate between pericardial and
epicardial cyst completely. This should broaden the spectrum of the
potential appearance of differentials like epicardial masses
intraoperatively. Role of cardiac magnetic resonance in tissue
characterization to avoid erroneous preoperative diagnosis can have
diagnostic importance. (9)
Coronary CT or angiography might be considered especially with regard to
the degree of adhesions and location of the coronary vessels. However,
it may not always exclude the possibility of involvement of coronaries
because some literature reported epicardial cysts with involvement of
the coronary vessels and CPB requirement to resect those cysts despite
having negative findings [1, 2].
VATS/thoracotomy might be the first option but when invasion to
important structures, including the left ventricle and coronary artery
is suspected, median sternotomy with CPB should be considered. Off-pump
resection might be indicated for uncomplicated cysts (8).
In our case, we were concerned about adhesions and close proximity of
the cyst to surrounding structures thus the less invasiveness of
thoracotomy was not considered beneficial enough to outweigh the risks
associated with inadmissible complication.
Surgical resection on CPB can be a safe option when cyst lies in close
proximity to important structures/erosion to ventricular wall. Detailed
and meticulous preoperative investigation should be considered in large
cyst in order to avoid any erroneous diagnosis.