Acknowledgments:
The study was supported by National Key R&D Program of China
(2018YFC0114602,2018YFC0114600) and the National Natural Science
Foundation of China (81000615).
Disclosure: None.
【Abstract】
We report a rare case of right ventricular angioleiomyoma in a 35-years
old man diagnosed by multimodality imaging, including echocardiography,
cardiac magnetic resonance imaging (CMR), Positron emissions tomography
(PET) and Computer tomography angiography (CTA). The imaging results
were finally confirmed by surgery. We present the clinical value of
multimodality imaging in diagnosing cardiac angioleiomyoma.
【Introduction】
Angioleiomyoma is a benign tumor with clear perimeter, composed of
bundles of mature smooth muscle and thick-walled blood
vessels1, described mainly occurs in the subcutaneous
or deep dermis,rarely happens in the heart. Although very rare, it can
cause serious consequences, even the most benign and smallest tumors can
lead to significant morbidity and mortality2.
Therefore, early diagnosis and treatment is very important.
Multimodality imaging, including cardiac magnetic resonance imaging
(CMR), Positron emissions tomography (PET) and Computer tomography
angiography (CTA) can make the diagnosis more accurate. We report a rare
case of right ventricular angioleiomyoma, presenting the significant
role of multimodality imaging in diagnosing.
【Case Presentation】
A 35-year-old male suffered from emaciation with no obvious cause for
more than five months. An unexpected right ventricle (RV) mass was
revealed by transthoracic echocardiography (TEE) in a physical check-up
of the local hospital, so he came to our hospital for the further
treatment. His vital signs and physical examination showed no special.
Our TTE showed an oval medium-high echo RV mass, measured 1.4 cm*1.1 cm,
with a rough surface at the basal level of the
interventricular septum (IVS), which swinged slightly and seemed to be
connected to the IVS by a pedicle about 0.3 cm wide, and the attachment
point was about 1.6 cm from the tricuspid annulus (Fig 1A).
Two-dimensional and three-dimensional transesophageal echocardiography
(TEE) indicated that the attachment of the RV mass seemed to be closely
connected with the tricuspid tendinous cord and adjacent to the aortic
root (Fig1B~D). Cardiac magnetic resonance imaging (CMR)
showed the soft tissue signal nodule presenting slightly T1
hypo-intensity and slightly T2 hyper-intensity which suggested high
possibility of benign neoplasm, but the attachment point was unclear
(Fig 1E). Positron emissions tomography (PET) showed that there was no
obvious abnormal increase of metabolism in the RV (Fig 1F). Computer
tomography angiography (CTA) also showed a filling defect measured about
1.0 cm in the RV (Fig 1G). The patient then underwent video-assisted
thoracoscopic cardiac mass resection and tricuspid valvuloplasty.
Thoracoscopy revealed the attachment of RV mass was approximately 1.5 cm
from the anterior-septal junction of tricuspid valve and adhered to
tendinous cord of tricuspid septal valve (Fig 1H). The resected tumor
was a slightly hard spherical mass with a capsule and had a gray-white
and red surface, measuring 1.2 cm*1.3 cm*1.2
cm (Fig 2A). Further
histopathological examination confirmed a right ventricular
angioleiomyoma with stromal mucinous change, the immunohistochemical
stain showed h-caldesmon and smooth muscle actin positive (Fig 2
B~F).
【Discussion】
Angioleiomyoma is a benign tumor with clear perimeter, composed of
mature smooth muscle cells with a prominent vascular
component3. The tumor tends to occur most commonly
within the 30–50 years age range and is approximately twice as
prevalent in women than in men4. It appears most
frequently on the extremities, especially the leg. Other localizations
such as uterus, ear, lip, nose, neck, and larynx have been also
reported. Heart localization is extremely rare. In fact, we found only
one previous report of cardiac
angioleiomyoma5.
Histogenesis of cardiac angioleiomyoma remains unclear, it is reported
that subendocardial multipotential mesenchymal cells, persistent tissue
of the endocardial cushion, or valvular interstitial cells may be the
origin6. Histologically
angioleiomyomas were classified as
solid, venous, and cavernous, of which the solid type being most
frequently observed. Myxoid or hyaline change may occur due to flow
disturbances within the tumor5. Although primary
ventricular angioleiomyomas are exceedingly rare in human, but not
uncommon in cattle. A study of cardiac angioleiomyoma in 44 cattle
suggested that angioleiomyomas are usually in subendocardial tissue and
swing slightly with the cardiac cycle but not within the
myocardium6. Also, the position of the tumors is
highly characteristic: all involved the valve complex (valves, chordae
tendineae, or papillary muscles). The overlying endocardium of the tumor
is smooth, without thrombosis and the cut surface of tumors is white or
red, or both. These findings are almost consistent with those of this
case and another patient reported in the literature5.
In addition to the high specificity of tumor location, angioleiomyoma
also has its imaging characteristics, and the advent of multimodality
imaging has made the diagnosis more accurate. Angioleiomyoma is usually
a well-circumscribed oval mass with a homogeneous echo texture on
US7. In this study, cardiac angioleiomyoma can swing
slightly with the cardiac cycle in TTE or TEE. Computer
Tomography(CT)or contrast-enhanced CT often show a soft density
tissue8. The tumor presents as a filling defect in
CTA. In MRI, it has been described in previous studies as a
well-circumscribed mass with an isointense or slightly hyperintense
signal relative to the muscle on T1-weighted images and a heterogeneous
and hyperintense signal on T2-weighted and STIR
images7. In addition, as a benign tumor,
angioleiomyoma usually do not cause increased metabolism in PET. The
imaging techniques described above can provide anatomical and
hemodynamic information of angioleiomyoma,which is conducive to
surgical planning.
In conclusion, we have reported a right ventricular angioleiomyoma, a
rare type of heart tumor. It should be considered in the differential
diagnosis of ventricular tumors.