In ALCAPA, the systemic arterial pressure (SAP) and PAP as well as the oxygen saturation (OS) levels are equal during the fetal period.[2] The pulmonary pressure falls and the ductus arteriosus closes in the neonatal period. The flow of the LCA reverses, and the perfusion pressure of this artery falls after closure of the ductus.[3] The major factor for determining the symptoms in patients with this condition during this period is the development of collaterals, and myocardial ischemia, and the degree of symptoms due to ischemia depends on the development of collaterals between the RCA and LCA.[3] Patients with well developed collaterals are defined as having adult-type ALCAPA while those without collaterals have the infantile-type of this syndrome.[3] Unless the latter type is diagnosed and treated, 90% of children die in their first year of life because of mitral regurgitation due to widespread myocardial ischemia and heart failure.[1,4]
Adult patients can be completely asymptomatic or present with angina, dyspnea, syncope, myocardial infarction (MI), arrhythmias, or sudden cardiac death,[5] with sudden cardiac death secondary to malignant ventricular arrhythmias being the most common presentation.[5] Today, an increase in the number of diagnostic procedures helps us to detect ALCAPA in older patients; however, well developed collaterals, symptoms, and life-threatening arrhythmias occur less frequently in older patients.[5] Tian et al.,[2] conducted a study that focused on the short-term follow-up of asymptomatic patients who refused surgical therapy and found that all were asymptomatic.
Echocardiography can show the abnormal origin of the LCA from the pulmonary artery, the left coronary artery flow via Doppler imaging, the dilated RCA, severe left ventricular dysfunction, and mitral regurgitation.[1,5] Since our patient had poor echogenicity, only an indefinite turbulent flow in the pulmonary artery could be detected by color and continuous wave Doppler.
Coronary angiography usually aids in the diagnosis by showing a dilated and tortuous RCA with collaterals to the LCA system along with variable degrees of shunting to the pulmonary artery.[6] In our case, the coronary angiography revealed that the LCA arose from the pulmonary artery, and aortography detected that that artery had collaterals arising directly from the aorta.
Coronary CT angiography is an important, noninvasive diagnostic tool used to delineate the abnormal origin, projection, and collaterals of coronary arteries.[2] In our case, we performed coronary CT in which we detected the abnormal origin of the LCA from the pulmonary artery and visualized the course of the LCA with its collaterals arising directly from the aorta.
The most important reason for symptoms associated with ALCAPA is deficient perfusion in the LCA region. The better the collaterals are, the better the myocardium perfuses. In our patient, the collaterals arose directly from the aorta and the ones from the RCA provided better perfusion in the LCA region, which contributed to the patient remaining asymptomatic.
Surgical correction is recommended in adult patients, especially those with symptoms and large left-to-right shunts; however, many authors have reported that surgery should also be performed on asymptomatic individuals in order to prevent ventricular arrhythmias, myocardial ischemia, and sudden death.[3] We recommended surgical correction to our patient, but he refused this option. He has been coming for regular controls since he was diagnosed in 2005 and has been taking part in sports activities with lower intensity without experiencing any symptoms.
Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital anomaly and in patients with this condition direct branches from aorta to LCA which provides good coronary perfusion should taken into consideration and aorta should be evaluated thoroughly.
Declaration of conflicting interests
The authors declared no conflicts of interest with
respect to the authorship and/or publication of this
article.
Funding
The authors received no financial support for the
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1) Ceylan Ö, Örün UA, Koç M, Özgür S, Doğan V, Karademir
S, et al. Anomalous coronary artery originating from the
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Dama 2013;21:122-6.
2) Tian Z, Fang LG, Liu YT, Zhang SY. Anomalous origin of
the left coronary artery from the pulmonary artery detected
by echocardiography in an asymptomatic adult. Intern Med
2013;52:233-6.
3) Ozer N, Deniz A, Doğan R. Left anterior descending
coronary artery originating from the pulmonary artery: a
rarity suspected during echocardiography. Turk Kardiyol
Dern Ars 2008;36:181-3.
4) Esmaeilzadeh M, Hadizadeh N, Noohi F. Anomalous Origin
of the Left Coronary Artery from the Pulmonary Artery
(ALCAPA) in an Old Adult. J Tehran Heart Cent 2011;6:148-51.