Anomalous origin of coronary artery originating from the pulmonary artery in conjunction with the aorticopulmonary window (APW) is known a rare but a significant anomaly. The occurrence of APW estimated in congenital heart patients is 0.15 and 52% of these patients have concomitant cardiac anomalies. The most common anomalies detected are aortic coarctation or interrupted aortic arch, Fallot tetralogy, and anomalous right pulmonary artery originating from the aorta. The presence of anomalous origin of the right coronary artery (RCA) from the pulmonary artery (ARCAPA) among the associated anomalies is less than 5%. Reference Izumoto, Ishihara, Fujii, Oyama and Kawazoe1,Reference Kutcche and Van Meirop2
Unlike truncus arteriosus, interrupted aortic arch, and transposition of great arteries, APW does not fall within “conotruncal” cardiac anomalies. It is not a cardiac anomaly caused by the delay in the migration of neural crest cells during the process of embryological development. Thus, co-occurrence with Di-George syndrome is not seen.
Aorticopulmonary septation is developed by matching conotruncal fusion during the embryological period. Truncus arteriosus divides off to form the aorta and pulmonary artery. In foetal life, pulmonary artery branches are formed with the healthy development of six pairs of aortic arcs in the right and left. If the development of the conotruncal margins is insufficient, a defect occurs in the aorticopulmonary septum. Therefore, it can be visualised in a broad spectrum from a defect right above semilunar valves to the interrupted aorta and from the detachment of the right pulmonary artery from the aorta. Reference Kirklin, Barratt-Boyes, Kirklin and Barratt-Boyes3
Determining the clinical condition of these patients is left–right shunt and increased pulmonary blood flow due to APW. Myocardial ischemia may not be noticeable due to left–right shunt at APW level and increased pulmonary artery pressure, and the presence of ARCAPA may be missed at diagnosis. Besides as a result of ARCAPA exposed high perfusion pressure due to APW and well-oxygenated blood, myocardial ischemia findings may not be seen. Isolated repair of APW in the presence of satisfying collateral circulation might cause myocardial ischemia because of the coronary circulatory steal phenomenon. Moreover, in the case of poor inter-coronary collateral circulation, isolated repair of APW may result in acute ischemia in the RCA blood supply region. Reference Bockeria, Berishvili and Krupianko4 It is challenging to diagnose coronary anomalies on transthoracic echocardiography (ECHO) because both large arteries are filled together. In most suspected cases, the diagnosis is made angiographically or intra-operatively during the surgical repair of the aortopulmonary window. Reference Morell, Feccia, Cullen and Elliott5
Case presentation
This report is based on a case of a 45-day-old male infant with APW and ventricular septal defect (VSD) and ARCAPA. A one-stage surgical correction was successfully performed to the patient.
A 45-day-old male infant weighing 3400 g was referred to our centre with a history of congestive cardiac failure, murmur, and tachycardia. The patient was tachypneic with marked inter-costal retractions. His pulse rate was 180 beats/minute. There was a systolic thrill at the left sternal edge in the third inter-costal space and a grade 4/6 ejection systolic murmur at the upper left sternal border. The liver was enlarged. The electrocardiogram showed sinus tachycardia and biventricular hypertrophy. Chest radiography showed a dilated main pulmonary artery, a prominent left ventricle, and plethoric lung fields. The cardiothoracic ratio was greater than 75%.
The echocardiographic evaluation showed dilatation of the left heart chambers. The left ventricular end-diastolic diameter was 24 mm. Left ventricular ejection fraction (LVEF) was 81%; there was no valve regurgitation. There was an atrial septal defect (ASD) with a diameter of 4.2 mm and a peri-membranous outlet VSD with a diameter of 4 mm. The gradient between the two ventricles was 35 mmHg. A large (approximately 6 mm) aortopulmonary defect could be seen in an anterosuperior location. The distance of APW to the pulmonary valve was 6.8 mm. The flow was laminar. Systolic pulmonary arterial pressure was 70 mmHg. The left main coronary artery was arising from the right sinus of Valsalva, but RCA was not identified. According to the ECHO, ARCAPA was suspected.
Computerised tomography (CT) done at the different centre was reported as APW based on vascular malformation of 6 mm in diameter and 10 mm in length, with long contrast material passage between the posteromedial wall and the medial wall of the pulmonary truncus. There was no finding of ARCAPA in CT (Fig 1).
Figure 1. Dotted line indicates pre-operative ECHO image of APW.
The patient was taken into operation with these findings. The operation was performed through a median sternotomy, with cardiopulmonary bypass, moderate hypothermia, and del Nido blood cardioplegia. After median sternotomy, the RCA originated from the pulmonary trunk could be evaluated clearly in the examination. The patient has also had an ARCAPA abnormality (Fig 2).
Figure 2. Anomalous origin of right coronary artery originating from the pulmonary trunk (ARCAPA) and the course of the aorticopulmonary window (APW) is shown by arrows, respectively.
The aorta was cannulated distally, well beyond the level of the APW. Bi-caval venous drainage was established. After initiating cardiopulmonary bypass, patent ductus arteriosus (PDA) was ligated, and tourniquets were placed and snugged around the right and left branch pulmonary arteries to ensure adequate systemic perfusion and delivery of cardioplegia solution to both coronary arteries. Following the cardioplegic arrest, the right atriotomy was made, and a venting catheter was inserted into the left atrium via ASD; an oblique incision was made in the aorta and main pulmonary artery. An APW was found posteromedial border of the aorta. After aortotomy, it was also observed that RCA originated from the pulmonary artery. There was the anomalous origin of the RCA from the right anterior aspect of the main pulmonary trunk with the ostium situated 0.7 cm inferior to the lower margin of the window (Fig 3).
Figure 3. Image showing anomalous origination of RCA from the pulmonary artery (from the right anterior aspect of the main pulmonary trunk) with the ostium situated inferior to the lower margin of the aorticopulmonary window. a = RCA (right coronary artery); b = APW (aorticopulmonary window).
Both coronary arteries were standard size. First off, VSD was closed with a patch through the right atriotomy. The position of the RCA ostium was unfavourable for direct transfer to the aorta. APW was closed with Takeuchi type repair with a baffle made from the bovine pericardium to take blood to the RCA from the aorta. The ASD was sutured through the right atrium. Aortic cross-clamp time was 55 minutes, and total cardiopulmonary bypass time was 89 minutes with a minimal temperature of 32oC. After correction, the left ventricular pressure was systolic max 82 mmHg and the right ventricular pressure was systolic max 50 mmHg. The post-operative course was uneventful. In the post-operative ECHO, there was no residual transition in ASD and VSD. LVEF was 70%, and no leak was observed through baffle reconstructed during repair of the APW. Right ventricle systolic pressure (RVSP) was calculated as 40 mmHg accompanying 1o.Tricuspid regurgitation. The patient was extubated post-operatively 6th day and discharged 15 days later after extubation.
Discussion
ARCAPA and APW are rarely seen together. Similar cases described in the literature are limited. In this case, ARCAPA was protruding from the left sinus of the pulmonary artery root to the posterior, and it rotated and extending from the pulmonary artery and anterior surface of the ascending aorta to the right atrioventricular groove. It was not suitable for transferring directly to the aorta. Both coronary arteries were in regular calibration, and there were no signs of collateral circulation. RCA was supplied by oxygenated blood due to the presence of wide APW, and contrary to isolated ARCAPA no myocardial ischemia was present. The patient had congestive heart failure, and pulmonary overflow findings correlated with the right to left shunt as a result of wide APW. At this stage, early diagnosis and surgery are vital in preventing congestive heart failure and pulmonary vascular disease.
Surgical methods performed in isolated ARCAPA or ALCAPA are direct implantation of the abnormal coronary artery to the aorta, implantation of the coronary artery to the aorta with a tube graft and Takeuchi type correction. Direct implantation and Takeuchi type correction are the two methods that have been used in our clinic so far in the correction of these extremely rare pathologies. Until now, implantation via tube graft has not been performed in our clinic.
Findings and clinic of those patients severely differ from isolated ARCAPA. In isolated ARCAPA patients, the left coronary artery is dilated and tortoise. In most cases, it gives large collateral branches to the RCA system. The presence of a left–right shunt in the low-resistance coronary artery system leads to stealing from the myocardium to the pulmonary system. This entity does not occur in the presence of ARCAPA along with APW, as ARCAPA is fed with high oxygen content blood flow connected to the left–right shunt.
It is challenging to recognise APW coexistence with ARCAPA and or ALCAPA echocardiographically as large arteries fill at the same time. Reference Jiten, Manpal, Alok, Manoranjan and Tek S6 Therefore, surgeons should start the operation as prepared for coronary artery anomaly. Sometimes, although rare, coronary artery anomaly and APW are seen together. To skip a possible diagnosis of coronary anomaly can lead to irreversible consequences.
The current surgical outcome of the patients with aortopulmonary window is excellent, even when surgery is performed at the age of more than 3 months. Reference Kumar, Singh, Thingnam, Mishra and Jaswal7 In a case described by Alakhfash et al, a newborn born at the 27th gestational week with 1000 g of APW and ARCAPA, was operated on after weighted 3000 g and 4 months old then had been discharged. Reference Alakhfash, Tagelden, Almesned and Alqwaiee8
Different techniques have been defined in the repair of APW with ARCAPA.
These are including of the direct transfer of coronary ostium to the aorta, plasty and rotation with pulmonary patch tissue, the formation of tunnel construction, and intra-pulmonary baffle. The last technique was described by Hamilton and Takeuchi in 1979 and was applied for the first time by Casillas in 1986. Reference Gabbieri, Guadalupi and Stefanelli9 We applied the Takeuchi procedure in our case and used the bovine pericardial patch for baffles, also closed the aorta and pulmonary arteriotomy with a patch made from the bovine pericardium to prevent the development of pulmonary stenosis.
Intra-operative management of the APW association with ARCAPA requires considerable attention. With the introduction of cardiopulmonary bypass, with the ligation of PDA, the pulmonary overflow is reduced. The flow restriction of the right and left pulmonary artery through tourniquet application during cardioplegia administration, and the effective cardioplegia administration to the coronary circulation, ensuring abnormal coronary artery taking blood from the aorta with the appropriate surgical technique and repairing the arteriotomies with a pericardial patch to prevent residual stenosis are critical steps in operation.
The complications encountered during the long-term follow-up of this procedure are tunnel obstruction, baffle leakage that causes coronary–pulmonary fistula, supravalvular pulmonary stenosis. Reference Dodge-Khatami, Mavroudis and Backer10 The diagnosis of these complications can be made by non-invasive methods such as transthoracic ECHO. In suspicious cases, invasive techniques such as catheter angiography and coronary angiography can also be used.
As seen in this case, it is crucial to expect all kinds of co-abnormalities in complex cardiac surgeries. One should keep in mind, the co-occurrence of ARCAPA with APW even though, this modality is seen rare. Utmost care should be taken during aortotomy as the coronary artery injury should be avoided.
In summary, we treated a patient with ARCAPA along with APW and VSD by successful one-step surgery. The patient was discharged without any problem by the successful management of the ARCAPA anomaly, which was detected intra-operatively by careful inspection after the suspicion in ECHO.
Acknowledgements
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Financial support
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest
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Ethical standards
The authors assert that all procedures contributing to this work comply with the ethical standards of the relevant national guidelines on human experimentation and with the Helsinki Declaration of 1975, as revised in 2008, and has been approved by our hospital’s ethics committees.
