Читать книгу Interventional Cardiology - Группа авторов - Страница 108

Views that reliably demonstrate the full length of each coronary segment while minimizing foreshortening and overlap for the RCA are shown in Figure 4.7b. Usually, the only two views required to demonstrate lesions in the proximal, mid, and distal RCA are LAO and RAO, because of the absence of side branches in these segments. Ostial lesions in the RCA are often detected in LAO but can be significantly foreshortened in this view. If stent placement is being considered, finding the least foreshortened segment can facilitate accurate positioning at ostium. The ostial segment and proximal RCA often lay perpendicular to the X‐ray beam in the AP cranial and LAO caudal views, despite variation in the origin of the RCA toward anterior or posterior. The lateral view with cranial angulation can identify occasional highly eccentric ostial lesions not clearly seen in other views. The lateral view can also help to better delineate lesions in the mid RCA or when right ventricular branches overlap the main vessel.

The distal RCA, PDA, and posterior left ventricular (PLV) branches lie posterior to the heart and require cranial angulation (in LAO) or caudal angulation (in RAO or AP) to be visualized without overlap. Many operators routinely include a third view, either AP cranial or LAO cranial, in addition to LAO and RAO as standard during diagnostic imaging.