Hoffmann R, Mintz G S, Pichard A D, Kent K M, Satler L F, Leon M B
Intravascular Ultrasound Imaging Laboratory, Washington Hospital Center, Washington, DC, USA.
Am J Cardiol. 1998 Nov 15;82(10):1168-72. doi: 10.1016/s0002-9149(98)00603-1.
The purpose of this study was to determine whether the thickness of the intimal hyperplasia (IH) layer that accumulates within Palmaz-Schatz stents is dependent on stent size. Intravascular ultrasound (IVUS) and quantitative angiographic (QCA) studies were performed after stent implantation and at follow-up (5.4 +/- 3.8 months) in 161 patients with 177 lesions treated with 221 Palmaz-Schatz stents. Stent and lumen cross-sectional area (CSA) were measured. IH CSA and thickness at follow-up were calculated and compared with stent CSA and circumference. Maximum IH CSA and thickness were measured at the smallest follow-up lumen CSA; mean IH CSA and thickness was averaged over the length of the stent. Maximum IH CSA measured 4.8 +/- 2.4 mm2, and mean IH CSA measured 2.8 +/- 2.2 mm2. Maximum IH thickness (at the smallest follow-up lumen CSA) measured 0.60 +/- 0.36 mm, and mean IH thickness (over the length of the stent) measured 0.30 +/- 0.19 mm. There was a weak, but significant correlation between mean and maximum IH CSA versus stent CSA (r = 0.215, p <0.0001 and r = 0.355, p <0.0001, respectively). However, there was no correlation between mean or maximum IH thickness versus stent CSA (r = 0.018, p = 0.643 and r = 0.056, p = 0.463, respectively) or stent circumference (r = 0.002, p = 0.956 and r = 0.069, p = 0.361, respectively). IH thickness was found to be independent of the stent size. This explains the known higher frequency of restenosis in smaller stents compared with larger stents.
本研究的目的是确定在帕尔马兹-沙茨支架内积聚的内膜增生（IH）层厚度是否取决于支架尺寸。对161例患者的177处病变植入221枚帕尔马兹-沙茨支架后，在随访期（5.4±3.8个月）进行了血管内超声（IVUS）和定量血管造影（QCA）研究。测量了支架和管腔的横截面积（CSA）。计算随访时的IH CSA和厚度，并与支架CSA和周长进行比较。在最小的随访管腔CSA处测量最大IH CSA和厚度；平均IH CSA和厚度在支架长度范围内进行平均。最大IH CSA为4.8±2.4mm²，平均IH CSA为2.8±2.2mm²。最大IH厚度（在最小的随访管腔CSA处）为0.60±0.36mm，平均IH厚度（在支架长度范围内）为0.30±0.19mm。平均和最大IH CSA与支架CSA之间存在微弱但显著的相关性（r分别为0.215，p<0.0001和r为0.355，p<0.0001）。然而，平均或最大IH厚度与支架CSA（r分别为0.018，p = 0.643和r为0.056，p = 0.463）或支架周长（r分别为0.002，p = 0.956和r为0.069，p = 0.361）之间均无相关性。发现IH厚度与支架尺寸无关。这就解释了与较大支架相比，较小支架中再狭窄发生率较高这一已知现象。
