Expansion Capacity of Drug-Eluting Stents in Patients with Left Main Coronary Artery Disease: An Intravascular Ultrasound Guided Study

Abstract

Aims: The aim of this study was to assess the expansion capacity ofcurrent commercially available Drug Eluting Stents (DES) with nominaldiameters of 3.5-4.0mm in patients with Left Main disease.Materials and Methods: This study was conducted on 50Patients who underwent percutaneous coronary intervention(PCI)for Left Main disease at Benha university hospitals and NationalHeart Institute. PCI was done with Drug Eluting Stents(DES) with large diameters of 3.5-4mm and post dilatation wasdone with non-compliant (NC) balloons with diameters of 4.5-5mm. Intravascular ultrasound (IVUS) was used to measuremaximal stent diameter and area.Results: Three commercially available DESs were used in ourstudy; XIENCE Xpeditionᵀᴹ, Ultimasterᵀᴹ and Onyxᵀᴹ. Maximal stentdiameter was 4.5±0.3mm and diameter expansion index was0.96±0.05. Maximal stent area was 14.67±2.06mm² and area expansionindex was 0.86±0.07mm². On IVUS images, significantlymore calcification< 90 ̊ was detected in the group with expansionindex ˂ 0.85 (68.4 percent versus 25.8%, P=0.003) comparedto the group with expansion index >0.85. We found that DESswith diameters of 3.5-4.0mm can be expanded up to diameter of5.3mm after post-dilation. No complications were reported in thestudied patients, including perforation or stent fracture.Conclusion: Current DESs with nominal diameters of 3.5-4.0mmcan be safely and effectively over-expanded to reach the predicteddiameters in the left main, but the presence of calcification>90 may affect the achievement of the predicted area.