Intravascular Ultrasound Assessment of Drug-Eluting Stent Coverage of the Coronary Ostium and Effect on Outcomes

When stenting an ostial or proximal coronary lesion, 1 fundamental decision is whether to extend the proximal end of the stent into the aorta (in the case of the left main [LM] or right coronary ostium) or into the polygon of confluence of the LM (in the case of the left anterior descending [LAD] ostium). Complete angiographic and intravascular ultrasound data and 9-month follow-up angiographic and clinical data were available from 459 patients with 138 ostial lesions (angiographic diameter stenosis within the ostium of ≥50%) or 321 nonostial lesions in which the proximal end of the stent ended at or near the coronary ostium. Strut protrusion was more frequent in the LM than in the right or LAD ostium (68% vs 59% vs 53%, p = 0.010). The length of strut protrusion was 3.4 ± 1.7 mm in the LM ostium, 1.7 ± 1.0 mm in the LAD ostium, and 2.4 ± 1.4 mm in the right ostium (p = 0.001). In contrast, incomplete stent coverage of the ostium was similar among the LM, LAD, and right coronary artery (23% vs 33% vs 28%, p = 0.084) with a residual uncovered segment plaque burden of 42 ± 11%. Ostial restenosis was similar between the lesions with versus without strut protrusion (3.2% vs 2.3%, p = 0.775) and between the lesions with incomplete versus complete stent coverage of the ostium (2.4% vs 3.0%, p = 0.100). Ostial restenosis was seen in only 2 of 61 lesions (3.3%) with acute malapposition. In conclusion, when treating an ostial or proximal coronary artery lesion with a drug-eluting stent, the decision of whether to protrude the proximal end of the stent or leave the ostium uncovered does not appear to be critical.