**3.3 Anomalous connection with the appropriate sinus (type III)**

An anomalous orifice of a coronary artery is usually linked with an ectopic ostium. Nevertheless, in rare postmortem observations (Frescura et al., 1998), a valve-like stenosis has been described with a ridge, consequence of an aortic wall fold that is in contact with an ostium in right position. Recently, a LMCA originated from the left sinus in the usual site, but with a slit-like orifice due to a tangential initial course associated with a short intramural segment, has been described (Angelini et al., 2010). An ectopic origin of a coronary artery in the appropriate sinus remains possible, but the limit between a true abnormality and a common variant may be tenuous, such as a connection in the lower half of the sinus, or near the commissural junction between the left and right cusps.

#### **3.4 Anomalous connection with the non-coronary sinus (type IV)**

ANOCOR from the non-coronary sinus proved by surgical or postmortem examination were previously described as exceptional. Nevertheless, a higher frequency of the latter is noticed in recent studies using tomographic imaging.

#### **3.5 Anomalous connection above the sinotubular junction (type V)**

A high take-off from the aorta at least 10 mm above the sinotubular junction is generally considered as an anomalous connection (Hlavacek et al., 2010). However, the height of takeoff judged to represent the abnormality is based on few solid data. Indeed, a level of 4 mm has been reported in a postmortem study (Frescura et al., 1998). Therefore, the criteria to determine an anomalous aortic origin above the sinotubular junction should be redefined with the contribution of non-invasive imaging. Usually, the ectopic vessel continues to arise above the appropriate sinus (figure 5).

Proximal Anomalous Connections of Coronary Arteries in Adults 191

In patients with anomalous connection with the pulmonary artery, the most commonly artery is the LMCA. Usually, the latter is connected with the left posterior pulmonary sinus, facing the left posterior aortic sinus. Numerous epicardial collateral vessels are observed between the anomalous coronary artery that arises from the pulmonary artery and the normal contralateral coronary artery that arises from the aorta (fig 7). An origin of the RCA

Fig. 7. Aortic angiography view showing an anomalous connection of the left main (white star) with the pulmonary trunk (black arrow) with an enlarged right coronary artery (white

Numerous other ANOCOR have been reported in the literature, but with a very low incidence. Beside anomalous connections in the aorta or the pulmonary artery, an ectopic origin from a brachiocephalic artery, bronchial artery or internal mammary artery is possible, but anecdotal. A rotation of the aortic root may modify the position of normal coronary origin regarding the pulmonary trunk or subpulmonary infundibulum. The latter

Data are numerous in literature about the angiographic prevalence of congenital coronary abnormalities. The latter are found in >1% including abnormalities of origin and

arrow) filling by a retrograde flow the left coronary circulation.

is on the border between a true ANOCOR and an acquired anomaly.

**3.8 Other abnormalities (type VIII)** 

**4. Prevalence** 

**3.7 Anomalous connection with the pulmonary artery (type VII)** 

from the pulmonary artery is less frequently than the LCA.

Fig. 5. Angiographic view showing a high aortic take-off (arrow) of the right coronary artery.

#### **3.6 Single coronary artery (type VI)**

The definition of a single coronary artery is often ambiguous in the literature. In our view, a single coronary should be clearly differenced from an ANOCOR with a single ostium, as described on figure 5. In both cases, the solitary vessel supplies the entire coronary circulation. Nevertheless, the flow is always antegrade beyond a single ostium, while a single artery supplies the coronary circulation of a part of the myocardium by a retrograde filling (figure 6). Moreover, with our definition, a single coronary artery is never associated with an abnormal proximal course.

Fig. 6. Volume-rendered computed tomography image showing a single coronary artery with a normal left ostium, and a circumflex coronary artery (arrow) supplying the myocardium usually fed by the right coronary artery (arrow head).

Fig. 5. Angiographic view showing a high aortic take-off (arrow) of the right coronary artery.

The definition of a single coronary artery is often ambiguous in the literature. In our view, a single coronary should be clearly differenced from an ANOCOR with a single ostium, as described on figure 5. In both cases, the solitary vessel supplies the entire coronary circulation. Nevertheless, the flow is always antegrade beyond a single ostium, while a single artery supplies the coronary circulation of a part of the myocardium by a retrograde filling (figure 6). Moreover, with our definition, a single coronary artery is never associated

Fig. 6. Volume-rendered computed tomography image showing a single coronary artery with a normal left ostium, and a circumflex coronary artery (arrow) supplying the

myocardium usually fed by the right coronary artery (arrow head).

**3.6 Single coronary artery (type VI)** 

with an abnormal proximal course.
