Piece them together - Corner Case -1​ : April 2021

Contributed by
Dr Megha Sheth
Consultant Radiologist
U N Mehta institute of cardiology and research centre, Ahmedabad, Gujarat

Dr Yashpal Rana
Consultant Radiologist
U N Mehta institute of cardiology and research centre, Ahmedabad, Gujarat

A 5 month old boy presented with poor weight gain and recurrent lower respiratory tract infections since birth. 2D-echocardiography suggested Hemitruncus Arteriosus where right pulmonary artery (RPA) was arising from ascending aorta and main pulmonary artery (MPA) was continuing as left pulmonary artery (LPA). He was referred to radiology department at U. N. Mehta institute of cardiology and research centre, Ahmedabad, Gujarat for MSCT angiography study to confirm the
diagnosis, define arch anatomy and to look for coronary anomalies.

See the images below.

Findings:   CT confirmed the diagnosis of Hemitruncus Arteriosus (HA) where RPA was arising from ascending aorta and also revealed ALCAPA –Anomalous origin of left coronary artery from right pulmonary artery.
Figure 1: MSCT axial oblique images showing RPA arising from ascending aorta (HA) and MPA continues as LPA.
Figure 2 A and 2 B: Axial oblique MIP and volume rendered images confirming anomalous origin of left coronary artery from RPA (ALCAPA).
Figure 3: Volume rendered image showing RPA arising from ascending aorta (HA) and anomalous origin of left coronary artery from RPA (ALCAPA)

Teaching Points

Hemitruncus Arteriosus is a rare congenital anomaly in which one of the branch pulmonary artery arises from ascending aorta and the other is continuation of MPA.

Combination of HA with ALCAPA from RPA is extremely rare. The usual clinical presentation of ALCAPA is myocardial ischemia and severe left ventricular dysfunction due to coronary steal. But in this case as the anomalous left coronary artery received blood at aortic pressure from RPA which was arising from ascending aorta, there were no signs of LV dysfunction. Hence it is a physiologically correct ALCAPA.

Anomalous coronary artery origin should always be defined by CT or MR imaging in case of HA, as such complex scenario changes surgical approach and surgical outcome.

References

  1. Kutsche LM and Van mierop LH. Anomalous origin of pulmonary artery from ascending aorta: associated anomalies and pathogenesis. Am J Cardiol 1988; 61:850-856.
  2. Sachin Talwar, Palleti Rajashekar et al. Hemitruncus, septal defect and anomalous coronary artery from pulmonary artery – Asian cardiovascular & thoracic Annals – 2012; 21(3):338-341.