Akiyama K, Sawatani O, Imamura E, Endo M, Hashimoto A, Koyanagi H
Department of Cardiovascular Surgery, Heart Institute of Japan, Tokyo Women's Medical College.
Nihon Geka Gakkai Zasshi. 1988 May;89(5):747-51.
Stent creep is often associated with malfunction of bioprosthesis. We measured the inward bending angle of the stent-post showing maximum bending (IBA) on 42 mitral porcine xenografts retrieved 1 to 12 yrs (mean 7.7 yrs) postoperatively at reoperation. Patients were 12 men and 28 women, ranging in age from 26 to 58 yrs. Mean +/- S.D. for IBA was 12.7 +/- 4.2 degrees(ds) in 14 valves being implanted for less than 7 yrs and 16.9 +/- 5.5 ds in 28 valves longer than 8 yrs (p less than 0.05). There was a significant difference in IBA between 36 valves of 25-29 mm size (16.3 +/- 5.1 ds) and 6 valves of 31 mm (10.3 +/- 5.5 ds) (p less than 0.05), but no significant difference between 23 Hancock valves (15.5 +/- 4.4 ds), 10 Angell-Shiley valves (16.2 +/- 8.6 ds) and 9 Carpentier-Edwards valves (14.4 +/- 3.7 ds). IBA showed a tendency to have large valve in the heart with small left ventricular end-systolic volume. The results showed that stent creeping phenomenon was not related to the material or design of stent-post, but tended to increase with passage of time in place. Furthermore, it was suggested that stent creep was induced by the mechanism of compression of the stent by the left ventricular wall.
支架蠕变通常与生物假体功能故障相关。我们测量了42个二尖瓣猪异种移植物上显示最大弯曲的支架柱向内弯曲角度（IBA），这些移植物在再次手术时于术后1至12年（平均7.7年）取出。患者包括12名男性和28名女性，年龄在26至58岁之间。植入时间少于7年的14个瓣膜的IBA平均±标准差为12.7±4.2度（ds），而植入时间超过8年的28个瓣膜的IBA为16.9±5.5 ds（p<0.05）。25 - 29毫米尺寸的36个瓣膜（16.3±5.1 ds）与31毫米的6个瓣膜（10.3±5.5 ds）之间的IBA存在显著差异（p<0.05），但23个Hancock瓣膜（15.5±4.4 ds）、10个Angell - Shiley瓣膜（16.2±8.6 ds）和9个Carpentier - Edwards瓣膜（14.4±3.7 ds）之间无显著差异。IBA显示出在左心室舒张末期容积小的心脏中瓣膜较大的趋势。结果表明，支架蠕变现象与支架柱的材料或设计无关，但倾向于随着在位时间的推移而增加。此外，提示支架蠕变是由左心室壁对支架的压缩机制诱导的。
