Keywords
left ventricular fibroelastoma recurrence - left ventricular cardiac tumor - transesophageal
echocardiography
Cardiac papillary fibroelastoma is a primary cardiac neoplasm with an unknown prevalence
but is increasingly detected by echocardiography.
A 70-year-old asymptomatic man (98 kg; 178 cm) was referred in 2014 to our hospital
for evaluation of two suspected cardiac tumors in the left ventricle after his first
open heart surgery for fibroelastoma via conservative sternotomy in year 2005. The
patient presented to our hospital with no neurologic, cardiac, or other signs or symptoms
of general discomfort before he was scheduled for surgery.
In 2005, after a singular transient ischemic event, a cardiac tumor was confirmed
by transesophageal echocardiography in the left ventricle intertwined in the papillary
muscle belly close to the mitral valve cusp. The tumor was surgically resected through
a median sternotomy with the mitral valve preserved. At that time, no visible residues
of the fibroelastoma had been left macroscopically, and no clinical complications
in the surgical and postoperative course were then observed. During the surgery in
2005, the tumor was found on the A1 segment of the anterior leaflet and on the posterior
chordae in two parts. The tumor was resected with visual confirmation. The histologic
evaluation indicated a primary cardiac papillary growth with a pale basophilic myxoid
stroma, with nuclear matrix eosinophilic without neoplasm potency ([Fig. 1A]). Annual echocardiography and regular blood tests showed no fibroelastoma present
or mitral valve dysfunction.
Fig. 1 Histologic results of fibroelastoma in left ventricular papillary muscle. (A) First
tumor (2005). (B) New fibroelastoma (2014).
Three years following removal of the fibroelastoma, a small formation of the tumor
was detected by echocardiography. The clinical course was uneventful; therefore, no
special treatment was indicated at that time. From 2013 to 2014, the tumor rapidly
grew, and the patient developed benign prostate hyperplasia, which was treated with
Doudart 0.4 mg (dutasteride + tamsulosin; GlaxoSmithKline, London, United Kingdom).
In 2014, the fibroelastoma recurred as detected by transesophageal echocardiography.
The function of the mitral valve was normal, but the tumor tissue was detected between
the papillary muscle and the chordae tendineae. Magnetic resonance imaging revealed
two separate mobile and noncalcified spherical structures (1 × 0.8 cm), attached to
the ventricular surface of the posterior leaflet of the mitral valve with intermediate
signal intensity on a steady-state free precession sequence and high signal on T2-weighted
sequences. Clinically, the patient presented with New York Heart Association class ≤ II
without any cardiac or neurologic symptoms at the time.
Operative Setting
The operation was performed through a median redo sternotomy with mild hypothermia
and cardiopulmonary bypass with anterograde cold crystalloid cardioplegia provided
by 1,500 mL of Custodiol (histidine-tryptophan-ketoglutarate; Koehler Chemie, Bensheim,
Germany). The inspection of the mitral valve through left transatrial aperture showed
formation of two solid tumors interwoven tightly in the papillary muscle bellies and
chordae ([Fig. 2]).
Fig. 2 Fibroelastoma recurrence on the mitral valve in vitro (year 2014).
A mitral valve reconstruction attempt was avoided due to the unsuccessful initial
surgical elimination of tumor, which led to the recurrence of the fibroelastoma. The
repeated histologic evaluation confirmed the imaging diagnosis hypothesis of the fibroelastoma
recurrence (6.5 × 3.5 × 0.7 cm and 1.5 × 1.2 × 0.7 cm; [Fig. 1B]).
The mitral annulus morphology allowed for implantation of a 33-mm Hancock II (Medtronic,
Inc., Dublin, Ireland) biological prosthesis for advanced age (>70 years) at the request
of the patient. The prosthesis was implanted in a typical manner using pledged 2–0
Ethibond sutures (Ethicon, Inc., Somerville, New Jersey, United States). Once the
sutures were knotted, it was important to verify proper placement of the biological
valve, to avoid paravalvular leaks. The left atrium was closed in the usual manner,
double-layered with 4–0 polypropylene monofilament. Anticoagulation therapy (vitamin
K antagonist) was required for 3 months after the mitral valve replacement.
The cross-clamping time was 55 minutes; the total cardiopulmonary bypass time was
75 minutes. The patient was transferred to the intensive care unit and was extubated
after 3.7 hours; time in the intensive care unit was <24 hours. Postoperatively, the
patient was discharged after 9 days in excellent physical and mental health. The postoperative
transesophageal echocardiography showed the correct position and proper function of
the prosthesis without any unusual technical or morphological errors. Postoperatively,
this patient showed no episodes of arrhythmia or neurologic adverse effects.
Discussion
The incidence of primary cardiac tumors is very rare (0.0017 to 0.33%) at autopsy
and forensic pathology studies.[1]
[2]
[3] The fibroelastoma consisted of a small papillary, pedunculated, and avascular tumor,
covered by a single layer of endothelium containing variable amounts of elastic fibrils
in the form of composed collagenous connective tissue in hyaline stroma.[4] The fibroelastoma tumors are typically located in more than 95% of cases in the
left ventricle. In 45% of these cases, the tumor is positioned on the aortic valve,
followed by mitral (36.4%) and pulmonary valve (8%).[1]
The hypothetical reasons for tumor development include the hemodynamic stress of blood
flow along the endocardium following endothelial damage and a possible disposal of
fibrin fibers that are used to form organized thrombus. Patients with fibroelastomas
who undergo surgical treatment tend to have large tumors with no infiltration of the
surrounding tissue.
Usually the fibroelastoma tumors that are resected in patients who have undergone
surgical treatment do not infiltrate the surrounding cardiac tissue. The relapse of
fibroelastoma was never described because it is a benign neoplasm with no propensity
to recur. The tumor in our case would not have been found without critical evaluation
of our patient's clinical case history when changing drug and surgical treatment for
another disease.
Surgical treatment is indicated in cases of neurologic manifestations and in hospitalized
patients suffering from syncope, transient ischemic event, or atrial fibrillation
following diagnostic imaging.[4]
[5] Surgery is also indicated after percutaneous persistent foramen oval closure,[6] or chest pain with ST-segment elevation as myocardial infarction concerning the
location of the fibroelastoma on the right or left coronary cusp. But long-term follow-up
studies using echocardiography for imaging have not been done yet, and therefore the
natural history or clinical manifestation of these tumors has not been presented except
in one non-Hodgkin disease case (of 23 patients) within 15 years follow-up.[7]
The surgical resection of fibroelastoma has a success rate of 83% with the valves
being preserved and is classified as a curative, safe, and well-tolerated procedure.[8]
[9]
[10]
[11] The matrix consists of elastic fibers, proteoglycans, and spindle cells that resemble
smooth muscle cells or fibroblasts. The tumor connective tissue contains longitudinally
oriented collagen with irregular elastic fibers.[12]
In our case, the mitral valve was replaced to prevent recurrence of the fibroelastoma
and a third operation on this patient. The mitral valve apparatus was excised and
replaced with a biological prosthesis. Three criteria in the decision-making process
to perform mitral valve replacement instead of tumor resection alone were crucial.
-
Because the fibroelastomas were adherent to almost all chordae and to the papillary
muscles, the removal of the tumors required the resection of too much material of
the subvalvular mitral valve apparatus including many chordae ([Fig. 2]). Furthermore, the chordae were very thin, which would complicate a proper surgical
resection by using many neochordae. The preservation of the mitral valve apparatus
seemed unreasonable, and successful reconstruction of the mitral valve would be unlikely
and unreliable.
-
During the first surgery for the removal of the fibroelastoma from the chordate macroscopically,
no remnants were seen. It was unlikely that all microscopic particles were removed
(especially those growing on the chordae) of the fibroelastoma. Our study showed a
recurrence of the fibroelastoma years later.
-
Considering the age of the patient, the probability of the mitral valve reconstruction
being complicated and unsuccessful, and the risk of recurrence of the tumor making
surgery again necessary, the clinical safety and efficacy for the patient was paramount.
Conclusion
Cardiac fibroelastomas are very rare, and their presence is often found in patients
with echocardiography by chance or after a neurologic event. In our case, routine
follow-up detected the recurrence of the tumor without any serious incident. To our
knowledge, there has been no published report on fibroelastoma recurrence in a cardiac
cohort. The surgical treatment with a biological mitral valve replacement was indicated
as a safe alternative to mitral valve repair to avoid oral anticoagulation therapy
in an elderly patient.
