CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 8, September 2012
e16
AFRICA
Discussion
The incidence of BWG syndrome is reported as one in 300 000
live births and it accounts for only 0.24 to 0.46% of all congenital
heart anomalies.
2
From the second month of life, as the vascular
resistance drops in the pulmonary vascular bed, pulmonary
pressure starts to decline as well. The ductus arteriosus closes
and flow from the left coronary artery reverses, which reduces
the perfusion pressure of the ectopic left coronary artery.
Insufficient blood supply and disturbed myocardial perfusion
may lead to the development of collateral circulation between
the right and left coronary arteries. If a well-developed collateral
circulation is present in these patients, both the perfusion
pressure and oxygen requirement of the myocardium can be met
to a certain extent. This collateral circulation determines both
the area of myocardial ischaemia and whether symptoms will
develop. If good collateral circulation develops in these patients,
it is termed adult type and if not, it is infantile type.
3
While adult patients can be completely asymptomatic,
they may present with angina, dyspnoea, syncope, myocardial
infarction, arrhythmia or sudden cardiac death. Sudden cardiac
death secondary to malignant ventricular arrhythmias is the most
common clinical presentation in adult patients.
4
Fig. 1. In TTE with colour Doppler, the parasternal
short-axis view shows abnormal blood flow through the
interventricular septum (A); the subcostal view shows
abnormal blood flow patterns through the free wall of the
right ventricle (B); the modified parasternal short-axis
view shows retrograde flow from the LAD into the pulmo-
nary artery and LAD orifice (C). Lv: left ventricle, rv: right
ventricle, la: left atrium, ra: right atrium, ivs: interven-
tricular septum, ias: interatrial septum. pv: pulmonary
valve, pa: pulmonary artery, lad: left anterior descending
artery.
Fig. 2. Selective right coronary angiography showing
the right coronary artery is ectatic and curly and the
LAD is retrogradely filled with collaterals from the RCA.
RCA: right coronary artery, LAD: left anterior descending
artery.
