DISCUSSION
Quadricuspid aortic valve (QAV) is a very rare congenital cardiac
anomaly with an incidence of 0.01–0.04%.3 Aortic
valve anomaly may be anatomically unicuspid, bicuspid or quadricuspid as
in our case. The most common of these variants is the bicuspid valve,
followed by the unicuspid valve.2,4 The mechanisms of
QAV development is not exactly known. Embryological truncus arteriosus
is thought to develop as a result of abnormal decomposition. In general,
after septation of the arterial trunk, three mesenchymal swellings
develop into semilunar leaflets of the aortic and pulmonary trunks.
However, in QAV, the fourth cusp emerges during the early stage of
truncal septation, resulting in either a different number of primordial
aortic leaflets or abnormal cusp proliferation.3
QAV is often in the form of an isolated anomaly. However, anomaly such
as coronary artery anomaly, atrial septal defect, ventricular septal
defect, patent ductus arteriosus, fallot tetralogy, sinus valsalva
fistula, subaortic fibromuscular stenosis, mitral valve regurgitation,
mitral valve prolapse, asymmetric septal hypertrophy, and transposition
of great arteries may be accompanied.1,5,6 In our
case, there was no other cardiac anomaly accompanying QAV, that is, it
was in the form of isolated QAV. In our case, there was no aortic
dilation that could be seen in some patients.
In patients with isolated QAV, clinical signs are generally not seen in
childhood, the symptoms mostly appear after the age of 40. Significant
valvular disorder often occurs after the 5th - 6th decade. Clinical
symptoms of patients with QAV often depend on the functional status of
QAV and associated disorders. There is often regurgitation in the valve,
but rarely may be stenosis. Clinical findings mostly develop as a result
of valve regurgitation. As valve regurgitation increases, there may be
symptoms of heart failure such as palpitations, chest pain, shortness of
breath, fatigue and syncope.7,8
When patients are evaluated quickly or carelessly, the diagnosis of QAV
may be overlooked or the patient may be misdiagnosed. Our case was also
evaluated by a pediatric cardiologist at the outer center, and the
transthoracic echocardiography performed there revealed a 1st degree of
regurgitation in the aortic valve. Meanwhile, although all other
laboratory evaluations were normal and the patient had no history of
ARF, the patient was taken to secondary penicillin prophylaxis,
considering the insidious rheumatic carditis. However, when we carefully
evaluated the patient with transthoracic echocardiography (TTE), we
noticed that the patient’s aortic valve was quadricuspid and 1st degree
valve regurgitation developed as a result of QAV. Therefore, we thought
that aortic regurgitation was not related to rheumatic carditis. After
the diagnosis of QAV, secondary prophylaxis applied to the patient every
21 days for rheumatic carditis was stopped.
With a careful TTE, almost all patients with QAV may be diagnosed. In
cases where valve anomaly is suspected and definitive diagnosis cannot
be made with TTE, Transesophageal echocardiography or Cardiak CT may be
needed for a definitive diagnosis.8,9 Approximately
25-50% of patients with QAV have to need surgical intervention in older
ages. Surgical options for QAV include aortic valve repair and aortic
valve replacement. Tricuspidalization is a preferred technique for QAV
repair.2,10
As a result; QAV is a very rare congenital cardiac anomaly. When
evaluating patients in terms of rheumatic fever, patients should be
evaluated in detail for monocuspid, bicuspid or quadricuspid aortic
valve in case of valve regurgitation, which is thought to develop as a
result of rheumatic carditis, with or without a patient’s history,
active complaint, or supportive laboratory finding. It should not be
forgotten that, as in our patient, if the patient with this valve
anomaly is mistakenly diagnosed with rheumatic carditis, this patient
will unnecessarily have to have an intramuscular depot penicillin every
21 days until at least 40 years of age or for life, which is a very
painful procedure for this patient and carries the risk of anaphylaxis.