902-4 Intravascular Ultrasound Analysis of Routine High Pressure Balloon Post-Dilatation After Palmaz-Schatz Stent Deployment

Abstract

To examine the effect of routine high pressure post-dilation (HPD) following Palmaz-Schatz stent deployment, intravascular ultrasound (IVUS) was used to measure stent expansion and luminal cross sectional area (LCSA) in 25 lesions (7 native vessels and 18 saphenous vein grafts). Following deployment, each stent was dilated to 14 atm with a non-compliant balloon regardless of angiographic appearance. QCA revealed a mean balloon size of 3.56 ± 0.52 mm, a balloon to artery ratio of 1.2, and a residual angiographic stenosis of -12.4%. IVUS was then performed within, as well as 5 mm proximal and distal to the stent. In a subset of 8 stents (32%), IVUS was also periormed before HPD. Measurements within the stent were compared to reference vessels 5 mm proximal and distal to the stent margins. HPD increased stent MLD from 2.9 to 3.5 mm (p = 0.03), and LCSA from 8.9 to 11.6 mm2(p = 0.01). LCSA was ≥ distal reference LCSA in 68%, ≥ proximal reference LCSA in 57%, and ≥ 60% of the average of proximal and distal reference vessel external elastic lamina areas (ECSA) in 96% of stents respectively. Minimum lumen diameter (MLD) was ≥ distal reference MLD and ≥ proximal reference MLD following HPD in 60% and 43% of stents respectively. By IVUS, struts appeared fully apposed to the arterial wall in 72% of stents, and the incidence of intraluminal dissection was only 2.4% following HPD.Download : Download high-res image (69KB)Download : Download full-size image 1) HPD can be safely performed following stent placement and significantly increases LCSA and MLD. 2) It depends on which specific angiographic or IVUS criteria are used to define “optimal stenting”, whether routine post dilatation of Palmaz-Schatz stents with a non-compliant balloon to 14 atm is or is not effective in achieving these goals.