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Figure 3 Nonoverlapping and Overlapping Sections in SES, SES+ED, BMS, and CDES

(A1 to D1) Representative low-power photomicrographs of all 4 stent groups—SES, SES+ED, BMS, and CDES—within the nonoverlapping stent segment. (A2 to D2) The neointima of overlapping SES, SES+ED, and BMS consists of an organized layer of smooth muscle cells in a proteoglycan-rich matrix. In contrast, CDES implanted arteries demonstrate impaired vascular healing with little neointimal growth at the overlap site (note that the struts of the innermost stent are mostly uncovered). (A3 to D3) High-power views from boxed areas in A2 to D2 of overlapping stent strut sections (Movat Pentachrome stain). Occasional giant cells populate the immediate vicinity of overlapping stent struts in all groups. (A4 to D4) Fibrin-rich areas were common in the area neighboring overlapping CDES struts, particularly those uncovered by an appreciable neointima (hematoxylin and eosin stain). Note the remnants of the polymer in the area once occupied by CDES struts (arrows), which are absent from SES, SES+ED, and BMS. Abbreviations as in Figure 1.