成人の冠状動脈瘻診断に対する心エコー図の果たす役割

伊賀幹二、泉知里、＊高橋秀一、小西孝

Summary

We retrospectively analyzed 7 cases of angiographically proved coronary artery fistula regarding the usefulness and limitation of transthoracic and transesophageal echocardiography. Three cases were coronary to right ventricular fistula, one coronary to left ventricle and pulmonary artery each and 2 cases of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). Proximal coronary arteries were normal in size in one case of pulmonary fistula although an aneurysm of the coronary artery and an anomalous vessel were present. Initial transthoracic echocardiography made a diagnosis in only 3 cases. After minute examinations, an abnormal channel was identified adjacent to the Valsalva sinus in 5 cases and it was proved to be a dilated coronary artery in 4 cases. A color flow signal was seen in the septal branch of the left anterior descending artery in a case of ALCAPA. Transesophageal echocardiography showed dilatation of a proximal coronary artery connecting to an enlarged vessel located in the atrio-ventricular groove. The maximal velocity across the orifice was measured in 3 cases. ALCAPA was diagnosed by transesophageal echocardiography because the enlarged left coronary artery disconnected to the left coronary cusp although the enlarged right coronary artery originated from the right coronary cusp. In two cases, many collateral vessels disturbed to discern the coronary oriface in the angiography, however, transesophageal echocardiography showed a more detail anatomy regarding orifice morphology.

Screening for coronary artery fistula is difficult by transthoracic echocardiography, however, transesophageal echocardiography in conjunction with transthoracic echocardiography provides synergistic information after the diagnosis made by angiography.