Frequency and Severity of Plaque Prolapse Within Cypher and Taxus Stents as Determined by Sequential Intravascular Ultrasound Analysis

We used intravascular ultrasound to evaluate the incidence, characteristics, and clinical sequel of plaque prolapse within drug-eluting stents. The influence of stent design on plaque prolapse has not been studied. Drug-eluting stents were serially expanded, first at 14 atm and then at 20 atm, with intravascular ultrasound imaging after each inflation. The stent, lumen, and maximum plaque prolapse areas were measured. The residual lumen area and percentage of plaque prolapse burden (maximum plaque prolapse area/stent area) were calculated. Plaque prolapse was divided into grades 1 ( 20% of the stent area. The frequency and amount of plaque prolapse neither increased nor decreased at higher (20 atm) inflation pressures. Lesions with prolapse were longer (p = 0.004), with a larger external elastic membrane area and greater plaque burden (each p