Cardiovascular Journal of Africa: Vol 32 No 4 (JULY/AUGUST 2021)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 32, No 4, July/August 2021 224 AFRICA
Case Reports
Caseous calcification of the mitral annulus mimicking
benign cardiac tumour of the mitral valve
Huanhuan Gao, Lei Yao, Yan Cheng, Chao Wu, Xiaoli Mei, Yun Mou, Lijun Jiang, Zhelan Zheng
Abstract
Caseous calcification of the mitral annulus (CCMA) is a rare
subtype of mitral annular calcification. It usually appears as
a large, round, mass-like calcification with an echolucent core,
which may be misdiagnosed as an intracardiac mass, cyst,
thrombus or abscess of the mitral valve.
We present a case report of CCMA that was misdiagnosed
by echocardiography as a benign tumour due to its atypical
imaging. The mitral valve mass was resected and it was patho-
logically confirmed to be a myxoid change with calcification.
Echocardiography is the preferred initial diagnostic tool.
Myocardial contrast echocardiography (MCE) is used to
evaluate the vascularity of intracardiac masses or mass-like
lesions, but neither echocardiography nor MCE is reliable for
identifying atypical lesions. Cardiac computed tomography
is helpful in establishing a diagnosis by showing dense calci-
fications, while cardiac magnetic resonance imaging is used
primarily as a credible tool. We therefore recommend that a
diagnosis should be made based on various imaging modali-
ties, if necessary, and operators should be skilled to avoid
misdiagnosis.
Keywords: caseous calcification, mitral annulus, masses, case
report
Submitted 14/1/21, accepted 27/2/21
Published online 7/5/21
Cardiovasc J Afr 2021; 32: 224–227
DOI: 10.5830/CVJA-2021-007
Mitral annular calcification is a common echocardiographic
finding in our daily work, and is considered chronic degeneration
of the mitral valve fibrous ring, involving mainly the posterior
leaflet of the annulus. Caseous calcification of the mitral
annulus (CCMA) is a rare variant of mitral annular calcification,
which tends to occur in the elderly, with female, hypertensive
individuals and patients with chronic renal failure or calcium
metabolism abnormalities being the most vulnerable.1
This disorder usually appears as a large, round, mass-like
hyperechoic lesion that may cause diagnostic mistakes. We present
a case of CCMA that was misdiagnosed by echocardiography as
a benign tumour located in the base of the posterior leaflet of the
mitral valve, accompanied by secondary mitral stenosis.
The study was approved by the Institutional Review Board
at the First Affiliated Hospital, College of Medicine, Zhejiang
University. The procedures were conducted according to the
principles of the Helsinki Declaration. Written informed consent
was obtained from the patient for publication of this case report
and the accompanying images.
Case report
A 64-year-old Chinese female with a suspicious-looking tumour
at the posterior leaflet of the mitral valve was referred to
our hospital for further diagnosis. She had no chest pain or
dyspnoea. The physical examination, electrocardiogram and
chest X-ray were unremarkable. Her vital signs were normal with
a heart rate of 94 beats/minute, a respiratory rate of 20 breaths/
minute, a body temperature of 37°C and a blood pressure of
134/80 mmHg. No cardiac murmur or thrill was present. Initial
laboratory tests, including serum creatinine (51 μmol/l), sodium
(136 mmol/l), chlorinum (97 mmol/l), potassium (4.89 mmol/l),
calcium (2.04 mmol/l) and magnesium (0.98 mmol/l) were all in
the normal range.
Four years earlier, the patient underwent a routine
echocardiography examination and a hyperechoic lesion in the
posterior leaflet of the mitral valve was discovered (Fig. 1A). It
was 15 × 9 × 8 mm with no significant mitral regurgitation or
stenosis. On presentation, echocardiography revealed that the
hyperechoic lesion had increased to 22 × 20 × 16 mm and was
attached to the posterior leaflet of the mitral valve (Fig. 1B). It
caused moderate mitral stenosis.
Myocardial contrast echocardiography (MCE) was further
performed to evaluate the vascularity of the mass and it was
found that it was a ring-enhancement mass with distinct borders
(Fig. 2A). Quantitative analysis revealed that when compared
to ventricle myocardium, the intensity of the mass was higher,
Echocardiography and Vascular Ultrasound Center, the
First Affiliated Hospital, College of Medicine, Zhejiang
University, Hangzhou, China
Huanhuan Gao, MD
Lei Yao, MD
Yan Cheng, MD
Chao Wu, MD
Yun Mou, MD
Zhelan Zheng, MD,
Department of Ultrasound, the People’s Hospital of Deqing
County, Zhejiang, China
Xiaoli Mei, MD
Department of Thoracic and Cardiovascular Surgery, the
First Affiliated Hospital, College of Medicine, Zhejiang
University, Hangzhou, China
Lijun Jiang, MD