The intracoronary stent implantation is regarded as an effective treatment modality to reduce restenosis. However, subacute stent thrombosis and subsequent anticoagulation therapy have been major problems after stenting. The high-pressure inflation stenting reduced the incidence of stent thrombosis and resulted in less need of anticoagulation therapy. We intended to analyze the high-pressure inflation stenting with intravascular ultrasound(IVUS) and to evaluate different IVUS criteria of optimal stenting.

One hundred and forty eight patients with 160 lesions were treated with 175 stents of various types. IVUS images were obtained after angiographic optimization (<10% of residual stenosis) with high-pressure inflation stenting. The quantitative and qualitative off-line measurements of IVUS parameters were performed.

More high-pressure or larger-sized balloon inflation was needed in 32 lesions (20%) after IVUS. The incomplete stent apposition was observed in 5 lesions (3%). The edge dissection occurred distally or proximally to stented site in 19 lesions (12%). The plaque prolapse was observed within the stent in 24 lesions (15%). In single stent implantation for discrete lesions, optimal stent expansion defined by IVUS was achieved in 69% with minimal stent lumen area of 90% of distal reference lumen area and in 75% with minimal stent lumen area of 80% of average reference lumen area. The IVUS criteria of minimal stent lumen area 9mm² and 7-9mm² was met in 29% and 29%, respectively. In stents implantation for diffuse lesions including long stent,multiple overlapping stents and hybrid stents implantation, optimal stent expansion defined by IVUS was achieved in 69% with minimal stent lumen area of 90% of distal reference lumen area and in 67% with minimal stent lumen area of 80% of average reference lumen area. The IVUS criteria of minimal stent lumen area 9mm² and 7-9mm² was met in 17% and 23%, respectively.

IVUS provided a valuable informations leading to additional intervention in 20% of the lesions after angiographic optimization with high-pressure balloon inflation. Even though additional interventions were performed with IVUS-guidance, the optimal stent expansion by IVUS criteria was achieved in about 70%. Therefore, we suggest that IVUS might be used more generally to improve the acute results after coronary stenting.