Abstract 3437: Intravascular Ultrasound Assessment of the Incidence and Predictors of Edge Dissections and Intramural Hematomas After Drug-Eluting Stent Implantation
Drug-eluting stent (DES) implantation strategies differ compared to conventional bare-metal stenting. However, coronary dissections after DES implantation have not been well studied.
Methods and Results: We used intravascular ultrasound (IVUS) to assess the incidence and predictors of edge dissections in 887 pts with 977 native coronary artery, non-in-stent restenosis lesions undergoing DES implantation. 82 dissections were detected (9.4% per pt and 8.4% per lesion); 51.2% (42/82) involved the proximal and 48.8% (40/82) the distal stent edge. Intramural hematomas occurred in 34.1% (28/82) of the dissections. Residual edge plaque area (8.0±4.3 vs 5.2±4.3mm2, p<0.0001), plaque burden (PB) (52±12 vs 36±15%, p<0.0001), plaque eccentricity (8.4±5.5 vs 3.9±3.3, p<0.0001), and calcific deposits (52.5 vs 35.6%, p=0.029) and stent edge symmetry (1.17±0.11 vs 1.14±0.08, p=0.019) were larger in dissections than non-dissections. The independent predictors of stent dissection were residual plaque eccentricity (OR=1.3, p<0.0001) and significant residual PB ≥50% (OR=6.1, p=0.0002). When reference edge segments with an intramural hematoma were compared to undamaged reference segments, residual plaque area, residual PB, and stent edge symmetry were similar; only residual plaque eccentricity was larger (8.4±5.6 vs 3.5±3.2, p=0.002) and calcific deposits more common (31.8% vs 27.3%, p=0.032) than at the non-hematoma site. When edge dissections with an intramural hematoma were compared to edge dissections without a hematoma, there were no significant differences except that residual plaque area in the hematoma group was smaller (6.4±2.5mm2 vs 8.9±4.6mm2, p=0.044) and stent edges less asymmetric (1.13±0.05 vs 1.20±0.12, p=0.009).
Conclusions: IVUS identified edge dissections after 9.4% of DES implantations. Residual plaque eccentricity and significant PB predicted coronary stent edge dissections supporting the approach to end the stent in the least diseased reference segment. However, technique is also important to avoid undue trauma to the vessel wall and hematoma formation because dissections in less diseased reference segments with an arc of normal vessel wall (greater plaque eccentricity) may evolve into an intramural hematoma.