Case Report

A single coronary artery with left circumflex artery crossing right ventricular outflow tract in tetralogy of Fallot with absent left pulmonary artery

Introduction

The incidence of anomalous coronary artery (ACA) in TOF is 2–9%. ¹ A singlecoronary artery arising from either the right or left coronary sinus is seen in 1.8-4.2% of these patients. ¹ About 2-10% of patients with TOF have an anomalous coronary artery crossing the RVOT thereby challenging the surgical skills of surgeon during RVOT reconstruction. ^1,2 TOF with unilateral absence of pulmonary artery is a rare variant with incidence of 0.95- 3.23%. ³ No association with single coronary artery and left circumflex artery crossing the RVOT has been described in these patients.

Case Presentation

A 11-year-old girl, weighing 21 kg presented with the complaints of dyspnea and cyanosis while playing with room air oxygen saturation of 75-85%. The diagnosis of TOF was confirmed by transesophageal echocardiography and cardiac catheterization study. The cardiac catheterization study showed single coronary artery arising from right aortic sinus with anomalous course of left circumflex artery crossing the RVOT (/Supplementary Video S1). There was absence of the intrapericardial and hilar segments of left pulmonary artery (). Multiple small aortopulmonary collaterals were seen separately supplying the left lung without reformation of the hilar branch pulmonary artery. The right pulmonary artery (Nakata Index Z score +2) and left ventricle (left ventricular end diastolic volume index > 30 ml/m²) were normal sized (). Patient was planned for primary single lung intracardiac repair. Intraoperatively, a single coronary artery was arising from right aortic sinus which was immediately dividing into right coronary artery, left anterior descending artery and left circumflex artery (). The right coronary artery had normal course. The left anterior descending artery was crossing RVOT far off from the pulmonary annulus. The left circumflex artery was crossing RVOT, very close to the pulmonary annulus (). Pulmonary annulus was hypoplastic with poststenotic dilatation of main pulmonary artery. The main pulmonary artery was continuing as right pulmonary artery with completely absent left pulmonary artery. The left lung was small and fibrotic with multiple small collaterals seen around the hilum without hilar reformation of the branch pulmonary artery. The handmade valved pericardial autologous conduit (12 mm diameter) with bicuspid pulmonary valve reconstruction using polytetrafluoroethylene membrane was prepared by the technique described by Schlichter et al. ⁴ The ventricular septal defect was closed using autologous glutaraldehyde treated pericardium. The hypertrophied infundibular muscle was excised. The native pulmonary valve was unicuspid and hypoplastic. Leaflet tethering was released. Hegar’s dilator of 7 mm size was negotiated through the hypoplastic pulmonary annulus. The valved pericardial autologus conduit was then anastomosed, first at the pulmonary end followed by the ventriculotomy end (). The post-operative right ventricular systolic pressure was 50% of systemic systolic pressure. The transesophageal echocardiography showed gradient of 8 mm Hg across the valved conduit and mild neopulmonary valve regurgitation (). The patient recovered uneventfully. The patient was discharged on 11^th post-operative day and is doing well in the follow-up period.

Close

Figure 1. (A) Left ventricle angiogram showing a single coronary artery arising from right aortic sinus with anomalous left circumflex artery crossing right ventricular outflow tract (B) Right ventricle angiogram showing main pulmonary artery continuing as right pulmonary artery with absent left pulmonary artery. MPA - main pulmonary artery, RPA - right pulmonary artery

Close

Figure 2. (A) Intraoperative view showing a single coronary artery arising from right aortic sinus dividing immediately into right coronary artery, left anterior descending artery and left circumflex artery. Left circumflex artery was seen crossing right ventricular outflow tract close to the pulmonary annulus (B) Intraoperative view showing pericardial autologus conduit with reconstructed bicuspid pulmonary valve using polytetrafluoroethylene membrane

Close

Figure 3. (A) Postoperative transesophageal echocardiography showing native unicuspid pulmonary valve and valved conduit. LV - left ventricle, PV - native unicuspid pulmonary valve, RVOT - right ventricular outflow tract (B) Postoperative transesophageal echocardiography with pulse wave doppler across the valved pericardial autologous conduit showing minimal gradient of 8 mm Hg

Discussion

Single origin coronary artery with ACA crossing the RVOT in TOF has been described in few studies. ^5,6,7,8 The branches of single coronary artery arising from either the facing or non-facing sinus can take various courses after take-off. ^5,6,7,8 The prepulmonic course of left circumflex artery crossing RVOT in TOF with absent left pulmonary artery has not been reported in the literature.

A major coronary branch crossing the RVOT poses a great surgical challenge to the surgeon leading to change the standard way of TOF repair. Injury to this coronary branch can lead to fatal life threatening complications. ¹ Various techniques of RVOT reconstruction in this group of patients include oblique ventriculotomy parallel to the course of ACA, tailored ventriculotomy, two patch repair, transatrial approach, double barrel repair and extracardiac right ventricle-to-pulmonary artery conduit. ^7,9 Despite of proper preparation, damage can still occur to the major anomalous coronary branch crossing RVOT and in that case emergency bypass grafting to the distal end of the severed artery has to be done to restore the blood circulation. ¹⁰

Conclusion

In conclusion, coronary anatomy should be clearly defined before surgery in patients with anomalous coronary artery crossing the right ventricular outflow tract in tetralogy of Fallot otherwise as it may test the surgeon’s skill and may also need simultaneous use of multiple tools from the surgeon’s armamentarium for successful surgical outcome in these patients.

Competing interest

None declared.

Ethical approval

Written informed consent was obtained from the patient for the publication of this case report.

Funding

No funds were received for this work.

Supplementary materials

Supplementary file 1 contains Video S1.

References

1. Humes RA, Driscoll DJ, Danielson GK, Puga FJ. Tetralogy of Fallot with anomalous origin of left anterior descending coronary artery Surgical options. J Thorac Cardiovasc Surg 1987; 94(5):784-787.
2. Tchervenkov CI, Pelletier MP, Shum-Tim D, Béland MJ, Rohlicek C. Primary repair minimizing the use of conduits in neonates and infants with tetralogy or double-outlet right ventricle and anomalous coronary arteries. J Thorac Cardiovasc Surg 2000; 119(2):314-323. doi: 10.1016/s0022-5223(00)70187-5 [Crossref]
3. Zhang GC, Wang ZW, Zhang RF, Zhu HY, Yi DH. Surgical repair of patients with tetralogy of Fallot and unilateral absence of pulmonary artery. Ann Thorac Surg 1997; 64(4):1150-1153. doi: 10.1016/s0003-4975(97)00822-9 [Crossref]
4. Schlichter AJ, Kreutzer C, Mayorquim RC, Simon JL, Román MI, Vazquez H. Five- to fifteen-year follow-up of fresh autologous pericardial valved conduits. J Thorac Cardiovasc Surg 2000; 119(5):869-879. doi: 10.1016/s0022-5223(00)70081-x [Crossref]
5. Kervancioglu M, Tokel K, Varan B, Yildirim SV. Frequency, origins and courses of anomalous coronary arteries in 607 Turkish children with tetralogy of Fallot. Cardiol J 2011; 18(5):546-551. doi: 10.5603/cj.2011.0011 [Crossref]
6. Gupta D, Saxena A, Kothari SS, Juneja R, Rajani M, Sharma S. Detection of coronary artery anomalies in tetralogy of Fallot using a specific angiographic protocol. Am J Cardiol 2001; 87(2):241-244, a9. doi: 10.1016/s0002-9149(00)01330-8 [Crossref]
7. Vastel-Amzallag C, Le Bret E, Paul JF, Lambert V, Rohnean A, El Fassy E. Diagnostic accuracy of dual-source multislice computed tomographic analysis for the preoperative detection of coronary artery anomalies in 100 patients with tetralogy of Fallot. J Thorac Cardiovasc Surg 2011; 142(1):120-126. doi: 10.1016/j.jtcvs.2010.11.016 [Crossref]
8. Ozkara A, Mert M, Cetin G, Saltik L, Sarioglu T. Right ventricular outflow tract reconstruction for tetralogy of fallot with abnormal coronary artery: experience with 35 patients. J Card Surg 2006; 21(2):131-136. doi: 10.1111/j.1540-8191.2006.00192.x [Crossref]
9. Saritas B, Ozker E, Vuran E, Yoruker U, Ayabakan C, Turkoz R. Total correction in tetralogy of Fallot with anomalous major coronary artery: an alternative method to conduit use. Cardiovasc J Afr 2012; 23(2):e8-10. doi: 10.5830/cvja-2011-004 [Crossref]
10. Kitamura S. Pediatric coronary artery bypass surgery for congenital heart disease. Ann Thorac Surg 2018; 106(5):1570-1577. doi: 10.1016/j.athoracsur.2018.04.085 [Crossref]