Читать книгу Interventional Cardiology - Группа авторов - Страница 221

During coronary angiography it is common to encounter unusual appearing lesions that elude accurate characterization despite thorough examination using multiple radiographic projections. The use of IVUS allows accurate characterization of unusual morphology: filling defects, aneurysms, and spontaneous dissections. While most filling defects are true thrombi, a small percentage are highly calcified plaque (Figures 8.8 and 8.9) or even calcified nodules, an unusual form of vulnerable plaque.

Figure 8.9 This patient underwent a previous PCI with DES implantation of a lesion, in the diagonal artery, during which the artery was dissected. Follow‐up catheterization showed both restenosis and a large aneurysm on angiography. The IVUS shows from proximal to distal (a to h) the body of the aneurism (asterix in the longitudinal view and c to h) and the eccentric proximal restenotic lesion (b). Notice that the adventitia stops at the point of transition from the vessel to the aneurysm (c and d), indicating loss of vessel wall integrity and making this, in fact, a pseudoaneurysm. Notice the double lumen from e to g; and normal vessel with three‐layer aspect in h.

In an IVUS analysis of 77 angiographically diagnosed aneurysms, 27% were true aneurysms (Figure 8.10), 4% were pseudoaneurysms (Figure 8.10), 16% were complex plaques, and 53% were normal arterial segments adjacent to stenoses [6]. In‐stent neoatherosclerosis has been recently described as an important mechanism of late stent failure (i.e. restenosis and stent thrombosis).

Figure 8.10 This young, female patient presented with STEMI and type 4 SCAD by angiography in the mLAD. IVUS showed a normal three‐layer aspect to the proximal vessel (a and magnified image in b). Notice the crescent aspect of the hyperechoic hematoma comprising the true lumen from c to h (arrows in e). FL indicates false lumen and TL true lumen; note a septal branch within the FL in panel F.

Courtesy of Dr. José Mariani Jr.