波动性高血压与中膜板层变化的动物实验

目的　为了验证和完善关于波动性血压可引起主动脉中膜板层分离 ,从而导致Stan fordB型夹层动脉瘤的假说。方法　通过犬的动物模型设计 ,同时加大血压的波动性和应用悬吊法来加大应力对主动脉弓与主动脉降段交界处的作用。结果　在施加血流动力学应力作用影响后 ,主动脉弓与主动脉降段交界处中膜可较明显地形成 3个板层区。结论　用本实验方法 ,验证了波动性高血压可以造成主动脉弓与主动脉降段交界处中膜板层的分离破坏。在一定角度上解释了StanfordB型胸主动脉夹层动脉瘤形成和发展趋势。     

主动脉脱套与TEVAR术中支架源性主动脉脱套

急性主动脉夹层发生时内膜撕裂,如果撕裂形态呈现为周径上的环形破口,破口远端的内膜会脱离主动脉管壁并形成独立的内膜管腔,这个管腔顺着血流方向塌陷之后就会形成顺行脱套病变,即主动脉脱套。主动脉脱套发病率低,其总数的90%发生在主动脉夹层自然病程中,也可以是胸主动脉腔内修复术（TEVAR）的并发症。随着近年TEVAR技术的普及和手术数量的增加,手术相关并发症的数量也逐渐增加,但是TEVAR术中支架源性主动脉脱套（ISAII）的报道极为有限。该病作为一种罕见的夹层或并发症,并不被大多数医生所熟知,因此本文旨在介绍主动脉脱套和ISAII的概念、特点、诊断、分型以及处理原则与方法、注意事项,为临床工作提供理论支持,让更多患者受益。出现在自然病程中的主动脉脱套,有时需要心电门控计算机体层成像血管造影或心脏超声结合使用才能明确诊断,这种病变大部分情况下可以在开放手术中直视下修补;但是在TEVAR手术中,脱套病变往往只能通过数字减影血管造影发现,而且大部分情况下优先推荐血管腔内技术修复。如果没有及时发现脱套病变,将会出现灾难性后果。在TEVAR术中,如果在常规造影后发现ISAII,首先需要保留手术器械和通路。其次需要造影明确脱套分型,根据不同的分型,分清主动脉结构的改变,选择不同的处理方案。ISAII分三型,Ⅰ型ISAII病变局限于胸主动脉支架覆盖部位,无需额外支架植入;Ⅱ型ISAII病变位于支架覆盖远端,但局限于胸主动脉段,治疗上需要在胸主动脉段植入覆膜支架,固定内膜团块,开通真腔;Ⅲ型ISAII病变位于腹主动脉段,最危险,对术者的手术决策和技术要求也最高。除了胸主动脉覆膜支架植入,还需要在腹主动脉段使用裸支架固定内膜团块,开通真腔血供。     

胸主动脉夹层动脉瘤与高血压的关系及处理

高血压一直被认为是胸主动脉夹层动脉瘤（thoracicaorticdissection，TAD）的重要病因。TAD病人中75％合并高血压[1]。我院自1998年开始进行了TAD的微创腔内隔绝术治疗，现将TAD合并高血压的治疗经验报告如下。材料与方法1.一般资料1998年9月至2001年12月我院共对116例StanfordB型TAD病人施行了腔内隔绝术。男96例，女20例；平均（54.9±13.6）岁（26～84岁）；其中合并高血压82例（既往已经诊断为原发性高血压者68例），其余合并症包括心功能不全46例（陈旧性心肌梗死4例，有经皮经腔冠状动脉成形术史2例），呼吸功能不全15例，陈旧…     

Stanford B型主动脉夹层术中主动脉内膜脱套的腔内处理策略

术中主动脉内膜脱套（AII）是胸主动脉腔内修复术（TEVAR）术中一种罕见但致命的并发症，补救处理难度大且易漏诊、误诊、误判，正确识别术中AII并快速有效地给予治疗是一大挑战。术中AII属于继发性AII，具体病因仍不明确，可能与手术操作原因和潜在的主动脉病变等原因相关。本文结合相关文献及临床诊疗经验，对主动脉夹层患者TEVAR术中AII的发生原因、分型、诊断评估要点及紧急腔内处置方法等进行介绍和探讨。首先，笔者提出基于脏器血流灌注的细化分型方案：即在原分型的基础上增加脏器分支缺血严重程度的评价，依据术中数字减影血管造影显示的脏器分支灌注情况细分为a、b两个亚型。新分型法的优势在于除了可以区分脏器缺血严重程度，还可用于指导腔内紧急处置策略。第二，对于疑诊术中AII的患者，需要进行术中详细造影确定分型。笔者建议分三步完成主动脉支架近端、支架远端造影及腹主动脉真腔内造影，这有助于明确近端锚定区的稳定性以及术中AII类型，确定灌注不良的脏器分支、严重程度及缺血阻塞类型，对下一步采取的补救措施至关重要。最后，腔内补救支架治疗效果良好且具备创伤小、术后恢复快等优势，已成为术中AII治疗的首选；腔内补救支架治疗应按照先近端再远端、先主干再分支的顺序进行。针对重建支架远端胸腹主动脉真腔血供，现有主流方案存在一定局限性，笔者推荐采用“两步法”方案重建主动脉真腔血供，该方案可以避免脱套内膜进一步向远端撕脱。     

胸主动脉夹层合并腹主动脉夹层动脉瘤的介入治疗

主动脉夹层（Aortic dissection,AD）是指主动脉壁的中层弹力纤维与平滑肌变性,在血流动力学变化影响下出现裂缝,强大的血液冲击局部撕裂的内膜而进入主动脉中膜,使中膜沿主动脉长轴方向分离并扩展,形成主动脉壁二层分离状态,是一种不常见但具有潜在灾难性的疾病。     

覆膜支架主动脉腔内修复治疗主动脉夹层78例

目的探讨主动脉夹层腔内修复术的疗效。方法2001年6月至2005年5月,行覆膜支架腔内修复治疗主动脉夹层78例。男71例,女7例;年龄31～80岁,平均(52.7±12.3)岁。StanfordB型76例,StanfordA型2例。术后随访1～47个月,平均(13.0±10.1)个月。建立数据库,分析其临床特点及疗效。结果近端内漏5例;升主动脉夹层5例,其中1例术中发生,4例分别在术后1、7d、5、13个月发生。术后30d内死亡4例(5.1%),2例死于升主动脉夹层破裂,1例死于急性肾功能衰竭,1例死于脑出血。术中脑梗塞1例。5例病人因覆膜支架远端再发现破口,行二次腔内修复术。1例因内漏行二次腔内修复术。随访期死亡3例(3.8%),分别死于消化道出血、升主动脉夹层破裂和死因不明。结论覆膜支架腔内修复术是治疗主动脉夹层的有效方法,但远期效果还有待进一步观察。     

胃癌合并胸主动脉夹层动脉瘤治疗成功1例

患者　男 ,63岁。因发作性胸背部疼痛 10年 ,加重 3h入院。即往有高血压病史 10年 ,服用降压药 ,血压控制在 15 0 /90mmHg左右。十二指肠球部溃疡病史 30年 ,未正规治疗。体查 :急性痛苦病容 ,血压 15 0 /10 0mmHg ,双肺呼吸音清晰 ,未闻及罗音。心率 64次 /min ,胸骨右缘第二肋间闻及舒张期杂音。腹平软 ,无压痛及反跳痛 ,未扪及包块。双侧足背动脉搏动正常。化验检查 :ALT 10 .7U /L ,SAT 2 4.3U /L ,LDH 163U /L ,CK 69U /L ,CK -MB8.0U /L ,Cr85 .8μmol/L ,肌钙蛋白 0 .0 5 μg/L。辅助检查 :胸片示心肺未见异常。心电图 :…     

带膜支架治疗Stanford B型胸主动脉夹层动脉瘤

近年来血管腔内支架隔绝术治疗胸主动脉夹层（TAD）取得了较好的效果。2002年8月到2005年9月，我们共收治Stanford B型胸主动脉夹层动脉瘤32例，均行支架治疗并取得满意效果，现总结报道如下。     

主动脉夹层动脉瘤的急救护理

主动脉夹层动脉瘤是指主动脉腔内的血液通过内膜的破口进入主动脉壁中层而形成的血肿.其基本病变为主动脉中层囊性坏死,病理变化为内膜撕裂、管壁剥离及血肿在壁层中蔓延,并将中层撕开,向内外及两侧膨出而形成局灶性夹层血肿,因此又称主动脉夹层血肿或主动脉夹层分离.     

胸主动脉B型夹层腔内修复术后逆向撕裂的外科治疗

目的 回顾分析11例胸主动脉Stanford B型夹层分离行腔内修复术后逆向撕裂为StanfordA型夹层病例,总结其特点及外科治疗经验.方法 2005年4月至2008年3月,手术治疗11例腔内修复术后逆向夹层病人.7例发生于支架术3个月内,夹层破口均位于支架附着处,人工血管远端均与支架吻合;4例发生于支架术3个月后,夹层破口与支架距离较远,人工血管远端吻合口与支架无关.结果 所有病人均康复出院,随访7～40个月,均生存,无严重并发症.结论 发生于腔内修复术后近期(＜3个月)的A型夹层可能与腔内修复术有关,术中人工血管可与支架直接吻合.发生于术后较长时间的A型夹层是否与腔内修复术有关尚需探讨.外科手术治疗可获良好疗效,术中良好的脑保护与远端吻合口处理是手术成功的关键.     

尿白蛋白排出率与 高血压肥胖之间关系的探讨

测定了７８７例糖耐量的正常者尿白蛋白排出率。结果显示ＵＡＥ中位数为５．２０μｇ／ｍｉｎ（１．１３－８７．１μｇ），伴高血压得ＵＡＥ明显高于正常血压者。在不同血压组中肥胖者的ＵＡＥ和服糖后２小时血糖高于非肥胖者。     

扩张程度和皮肤血运关系的实验研究

目的研究扩张皮肤血运和扩张程度的关系。方法以扩张容量和扩张皮肤面积作为扩张程度的指标，观察猪皮肤在不同程度超量扩张下的皮肤激光多普勒血流值（LDF）和血管造影。结果超量扩张下LDF呈下降的趋势，而血管密度却是增加的，主要以小静脉和微小静脉的增生扩张为主。结论超量扩张下虽然皮肤血管密度增加，但皮肤血运却逐渐下降。本文浅略解释了这一特殊现象的机制。     

Experimental study of the relationship between alterations in tissue perfusion and anastomotic patency

It is generally believed that alterations in perfusion which endanger a free flap or replant are directly related to thrombus formation and obstruction of blood flow at the anastomotic site. Recent experimental work in our laboratory suggests that the presence of platelet emboli downstream in the microcirculation might be responsible at least in part for postoperative perturbations in perfusion. To determine whether changes in tissue perfusion can occur in the absence of corresponding changes in anastomotic patency we studied microvascular blood flow in the exposed rat cremaster flap model. We made continuous measurements of both anastomotic patency and downstream microcirculatory perfusion following small vessel repair. Using this approach we found that during one hour after clamp release and reperfusion in the 10 animals studied, pedicle artery blood pressure, which indicates pedicle patency in this model, was functionally normal 97% ± 2 of the time while blood flow in the downstream tissue (cremaster) remained normal an average of only 65% ± 7 of the time. In most cases these flow alterations were associated with the presence of visible platelet emboli in the microcirculation. From these studies we conclude that when flap perfusion failure temporarily occurs, a microsurgeon must consider not only the anastomosis but also the downstream microcirculation when searching for a possible cause. © 1993 Wiley-Liss Inc.     

Preliminary study on relationship between vertebral fracture and aortic calcification in postmenopausal women

The prevalence of aortic calcification and osteoporosis increases with age. Several studies have postulated a direct relationship between the two disorders, suggesting that aortic calcification results from a redistribution of skeletal calcium in osteoporosis. We have undertaken a case-controlled study to reevaluate the possible relationship between the two age-related processes. Lateral spine radiographs of 122 postmenopausal Turkish women were analyzed to determine the presence or absence of vertebral fracture (n ₁=44 andn ₂=78, respectively). Abdominal aortic calcification was quantified in both groups using a subjective grading system (from no calcification to dense calcification adjacent to three vertebrae) and a semiquantitative method. Using the subjective method, the prevalence of aortic calcification increased from 41% in subjects aged 50–65 years to 78% in those over 75 years of age (И²=10.8;P<.005). The prevalence of aortic calcification was similar in women with and without vertebral fracture (60.0%vs 57.7%;P=.63). Using the semiquantitative method, there was no significant difference in the severity of abdominal aortic calcification between subjects with and without vertebral fractures (P=.74). Using logistic regression, the direction of the odds ratio suggested a greater risk of vertebral fracture in the presence of moderate or severe aortic calcification (1.3; 95% CI 0.5–3.9) and multiple loss of intervertebral disk spaces (2.0; 95% CI 0.6–7.4), but the number of subjects was small and the confidence intervals wide. These results do not support the hypothesis of a direct relationship between calcification and vertebral osteoporosis as a result of calcium redistribution in postmenopausal women. It is likely that factors other than vertebral deformity are of importance in the development of aortic calcification in the elderly.     

In-vitro study on the relationship between progressive sinotubular junction dilatation and aortic regurgitation for several stentless aortic valve substitutes.

OBJECTIVE: Stentless aortic valves are widely used due to their excellent hemodynamic properties. However, if the subcoronary implantation technique is used later dilatation of the sinotubular junction (STJ) can cause regurgitation. The aim of the study was to determine the dilatation tolerance of two commercially available stentless xenografts and fresh aortic and pulmonary roots against such dilatation. METHODS: Four groups each comprising five specimens of fresh porcine aortic roots, pulmonary roots, Medtronic freestyle or Toronto SPV Xenografts were tested in a mock circulation using a special device for gradually increasing the diameter of the sinotubular junction. The smallest diameter D(r) where regurgitation occurs was measured and correlated with the starting diameter D(a) and expressed as per cent values. Opening and closing patterns were obtained by a high speed camera and flow characteristics were determined. RESULTS: The highest dilatation tolerance of STJ was found in the fresh porcine aortic roots (165%+/-10) followed by fresh pulmonary roots (146%+/-12), the Freestyle (143%+/-4) and the SPV (132%+/-5) bioprostheses. All differences were significant with P< or =0.05 except that between the fresh pulmonary roots and the two commercial available bioprostheses. CONCLUSIONS: Our results indicate that aortic homografts provide higher resistance against regurgitation induced by dilatation of the STJ than an autograft or the stentless xenografts, Freestyle xenograft followed by the Toronto SPV. The use of the full-root technique should be considered if aortic dilatation seems to be likely.     

腹主动脉瘤与CD40的关系

目的 探讨腹主动脉瘤(AAA)发病与患者血清CD40及其配体(CD40L)浓度的相关性.方法 对30例诊断明确的腹主动脉瘤患者(病例组)与26例健康人群(正常组)进行对照研究,酶联免疫吸附试验(ELISA)双抗体夹心法测定标本中CD40和CD40L水平,应用统计学独立样本t检验分析CD40/CD40L与腹主动脉瘤的关系.结果 病例组血清CD40浓度为(96.20±26.26) ng/L,高于正常组的(76.22±6.39) ng/L,两者差异有统计学意义(P＜0.05).病例组血清CD40L浓度为(746.20±215.46) ng/L,明显高于正常组的(503.07±75.32) ng/L,两者差异有统计学意义(P＜0.05).结论 AAA患者血清CD40和CD40L浓度明显高于健康人群,提示CD40/CD40L可能参与了AAA的发病.     

The relationship between the severity of erectile dysfunction and aortic stiffness

Aortic stiffness increases in patients with erectile dysfunction (ED) but it is not known whether aortic stiffness affects the degree of ED. In the present study, we aimed to determine whether there is any relationship between aortic stiffness and the severity of ED. Patients with ED were divided into 3 groups according to the International Index of Erectile Function (IIEF) scores. Mild ED was named as group 1, moderate ED as group 2 and severe ED as group 3. The values of fasting blood glucose (FBG), serum lipid values, total testosterone (T. tes), and free testosterone (F tes) were recorded. Aortic stiffness was determined by pulse wave velocity (PWV) and augmentation index (AIX) measurements. The mean or median values of the laboratory parameters among the groups were similar (p > .05). No statistical difference was found between the groups in terms of AIX value (p = .386). Mean PWV values were calculated as 7.26, 8.30 and 8.78 in group 1, group 2 and group 3 respectively. PWV values were significantly different between groups (p < .0001). PWV values were found to be increased with increasing severity of erectile dysfunction.     

The relationship between aortic wall distensibility and rupture of infrarenal abdominal aortic aneurysm

OBJECTIVE: A more accurate means of prediction of abdominal aortic aneurysm (AAA) rupture would improve the clinical and cost effectiveness of prophylactic repair. The purpose of this study was to determine whether AAA wall distensibility can be used to predict time to rupture independently of other recognized risk factors. METHODS: A prospective, six-center study of 210 patients with AAA in whom blood pressure (BP), maximum AAA diameter (Dmax), and AAA distensibility (pressure strain elastic modulus [Ep] and stiffness [beta]) were measured at 6 months with an ultrasound scan-based echo-tracking technique. A stepwise, time-dependent, Cox proportional hazards model was used to determine the effect on time to rupture of age, gender, BP, Dmax, BP, Ep, beta, and change in Dmax, Ep, and beta adjusted for time between follow-up visits. RESULTS: Median (interquartile range) AAA diameter was 48 mm (41 to 54 mm), median age was 72 years (68 to 77 years), and median follow-up period was 19 months (9 to 30 months). In the Cox model, female gender (hazards ratio [HR], 2.78; 95% CI, 1.23 to 6.28; P =.014), larger Dmax (HR, 1.36 for 10% increase in Dmax; 95% CI, 1.12 to 1.66; P =.002), higher diastolic BP (HR, 1.13 for 10% increase in BP; 95% CI, 1.13 to 1.92; P =.004), and a decrease in Ep (increase in distensibility) over time (HR, 1.38 for 10% decrease in Ep over 6 months; 95% CI, 1.08 to 1.78; P =.010) significantly reduced the time to rupture (had a shorter time to rupture). CONCLUSION: Women have a shorter time to AAA rupture. The measurement of AAA distensibility, diastolic BP, and diameter may provide a more accurate assessment of rupture risk than diameter alone.     

同种瓣移植后钙含量与免疫排斥反应的关系

目的 探讨同种异体带瓣大血管移植后钙含量与免疫排斥反应的关系。方法同种异体带瓣主动脉腹主动脉异位移植大鼠，随机分为异基因组（SD大鼠为供体，Wistar大鼠为受体）和同基因组（受体供体为同一种系的近交系大鼠）。各组随机分为5个小组，每组8只，分别于术后2,4,8,12、16周使用流式细胞仪测定大鼠CD25、CD71的表达，并且取出移植物，原子火焰吸收法测定钙含量，并对移植物进行光镜和电镜观察，同时免疫组化测定CD40L的表达。结果（1）异基因组移植后各个时间段的CD40L、CD25和CD71的表达均较同基因组高（P〈0．01），异基因组CD23、CD71和CD40L表达的高峰时间段主要在移植后早期（2-4周），此后的表达水平逐渐回落，12周后维持在低水平。（2）异基因组的钙含量从4周开始升高，随着时间的推移，逐渐升高，在12周达到高峰。同基因组各个时间段的钙含量无差别（P〉0．05）。（3）移植后异基因组出现内皮细胞脱落和平滑肌细胞坏死。结论同种瓣移植后的钙含量与免疫关系密切；移植后4周才开始钙化，随着时间的推移，钙含量逐渐升高，在12周达到高峰；移植后不同的时间钙含量并不与当时的免疫排斥水平正相关，但二者互相影响。