转录因子E2F与血管再狭窄的研究进展

E2F是调控细胞周期进程一个关键的转录因子,而且在血管再狭窄的病理过程中也起着非常重要的作用.对上述问题的了解,将有助于血管再狭窄防治的研究.     

Real-world clinical practice of intracoronary radiation therapy as compared to investigational trials.

Intracoronary radiation therapy (IRT) is well established in clinical practice as an effective treatment for in-stent restenosis. We aimed to determine if the 6-month clinical outcome of patients treated postapproval for marketing [commercial radiation (CR)] is equivalent to those patients enrolled in the Washington Radiation for In-Stent Restenosis Trials [Gamma WRIST and Beta WRIST; investigational radiation (IR)]. The 6-month clinical outcome of 110 consecutive patients with 125 lesions who received IRT (gamma, (192)Ir, 15-18 Gy, n = 6; or beta, (32)P, 20 Gy, n = 20; or (90)Sr/Y, 18.4-23.0 Gy, n = 99) in CR was compared with the 6-month clinical outcome of 117 patients with 117 lesions who received IRT ((192)Ir, 15 Gy, n = 65, in Gamma WRIST; and (90)Y, 20.6 Gy, n = 52, in Beta WRIST) in IR. Patients in CR were treated with wider radiation margins. The CR received antiplatelet therapy for at least 6 months and the IR for 1 month. The baseline characteristics of both groups were similar. Use of atheroablation devices was less in CR than IR (15.2% vs. 32.8%, respectively; P = 0.001). The overall major adverse cardiac events (death, Q-wave myocardial infarction, and target vessel revascularization; 18.2% vs. 29.1% in IR; P = 0.05) were significantly lower in the CR when compared with patients in the IR. The real-world clinical practice of IRT demonstrates lower events and better clinical outcomes. This is most likely a result of implementation of the lessons learned from the clinical trials such as optimizing the dosimetry by using a higher dose, treating wider margins to minimize edge effect, and administering prolonged antiplatelet therapy to abolish late thrombosis.     

不同形状血管中医用支架扩张力学行为的研究进展

血管支架介入术由于其微创性和高效性已经成为目前治疗由血管狭窄所引发的冠心病的主要治疗手段,但支架内再狭窄却是影响支架远期效果的最大障碍,严重制约了其实际疗效。首先从支架内再狭窄的形成机制出发,从固体力学角度回顾力学环境对再狭窄的影响,并主要阐述近年来支架在圆直、锥形、分叉、弯曲4种不同形状血管内扩张的研究进展,特别是从支架扩张对血管应力及血管形状的改变与再狭窄的相关关系方面进行综述。最后,针对不同血管形状对支架扩张的影响,提出一个旨在提高支架扩张性能及减少支架内再狭窄的血管支架多目标优化设计方法。     

Use of the porous balloon in porcine coronary arteries: rationale for low pressure and volume delivery

Using agents administered systemically, attempts to control the restenotic myoproliferative response associated with angioplasty have been unsuccessful. The porous balloon has the advantage of achieving high local concentrations by directly infusing agents into the arterial wall. The purpose of this study is to identify any acute and chronic morphological changes in swine coronary arteries infused with normal saline through the porous balloon at different driving pressures. In order to establish the safety of local arterial wall infusion through the porous balloon, swine underwent porous balloon infusion of 3,6, or 10 ml of saline at 5 atmospheres, or infusion of 3 ml of normal saline delivered at either 2, 5, or 10 atmospheres of pressure into the normal left anterior descending and left circumflex arteries. To assess the histopathologic alterations induced by the porous balloon, sized 1.1 to 1 with respect to the artery, animals were sacrificed either immediately after porous balloon infusion or 14 days later. Acute vessels were evaluated for the presence of medial injury, disruption and/or dissection, whereas chronic vessels underwent morphometric analysis measuring the residual luminal area (Lumen area/Intimal area + Lumen area) and the maximal intimal thickness. Adequate adventitial penetration was confirmed by infusing as little as 2–3 ml of methylene blue at 2 atmospheres of pressure. Infusion of 3 ml of normal saline at 2 atmospheres resulted in minor focal medial edema and disorganization, detected both acutely and 14 days after porous balloon infusion. At delivery pressures of 5 or 10 atmospheres, proportionally more acute injury was noted and measurable neointimal lesions were observed 2 weeks after infusion. These data indicate that porous balloon infusion of 3 ml of normal saline at 2 atmospheres was safe and resulted in only minimal medial edema of normal swine coronary arteries. Higher pressure or volume delivery proportionally increased the degree of injury and contributed to the development of neointima.© 1993 Wlley-Liss, Inc     

Accumulation of macrophages in the arterial vessel wall following experimental balloon angioplasty

Smooth muscle cell (SMC) proliferation is a key event in thedevelopment of restenosis after balloon angioplasty, and itis thought that macrophages play an important role in the complexprocess of activation ofSMCs after vascular injury induced byballoon angioplasty. The study was designed to determine the time course of the accumulationof macrophages in the intimal layer following experimental balloonangioplasty. To determine the extent and time course of the accumulationof macrophages after experimental balloon angioplasty, an intimalatheroma was produced by repeated weak electrical stimulationof the right carotid artery of 45 male New Zealand White rabbits.Additionally, the animals received an 0.5% cholesterol dietduring the 28 days of plaque development. Transluminal balloonangioplasty was subsequently performed. At 3, 7, 14, 21, 28and 42 days after balloon treatment the vessels from at leastfive animals from each group were excised and analysed for thepresence of macrophages using immunocytochemical techniques.In one group of five animals plaque development occurred withoutsubsequent balloon angioplasty; the animals were killed after21 days (sham group). SMCs were identified by immunohistologicalstaining of -actin. Intimal thickening increased after dilatation from 137 ±62µm (control group without balloon treatment) to 244 ±47 µm in the 42 days after angioplasty (P<0.05). Thepercentage of macrophages in the intimal layer displayed a significantincrease (P<0.01) at 14 days after angioplasty (9.1 ±4.3% vs 2.0 ±1.7% in the control group). This increasepersisted up to 21 days after intervention (8.0 ± 3.3%)and was significantly increased in comparison to the sham groupwith 3.1 ± 0.8% (P<0.05). Twenty-eight days afterballoon dilatation the amount of macrophages in the intima haddecreased (1.6 ± 1.6%), and was comparable to the pre-interventionalcontrol group. These results demonstrate that the occurrence of macrophageswithin the area of tissue injury is a delayed phenomenon andcontributes to the vascular response to injury.     

Intracoronary brachytherapy, a promising treatment option for diabetic patients: Results from a European multicenter registry (RENO).

Despite advances in the interventional treatment of coronary disease, diabetics still have double the case fatality rate as nondiabetics. The purpose of this analysis from the Radiation in Europe With Novoste (RENO) registry was to assess the clinical and angiographic 6-month outcome of diabetic patients in comparison to nondiabetic patients after localized beta-radiation. A total of 1,098 patients (83.8% with in-stent restenosis) treated with the Novoste Beta-Cath system in Europe were enrolled in the RENO registry. Diabetes was, irrespective of the type of lesion treated, no significant risk factor for major adverse cardiac events or target vessel revascularization. Individuals with diabetes (n = 256) and without diabetes (n = 833) displayed no significant differences concerning clinical or angiographic endpoints. Vascular brachytherapy appears to be the first technique to even out the increased risk of diabetic patients undergoing percutaneous coronary interventions in the routine clinical setting. Thus, intracoronary brachytherapy represents a promising treatment option for diabetic patients.     

Safety and efficacy of drug‐eluting balloons in percutaneous treatment of bifurcation lesions the DEBIUT (drug‐eluting balloon in bifurcaton utrecht) registry

Aims: The transradial (TR) approach has potentially lower complication rates than transfemoral (TF) approach coronary angiography. However, it may be technically more challenging, especially in elderly patients with alterations in vascular anatomy. We thus determined success rates, procedural data, and complication rates of TR angiography in comparison to the TF approach in elderly patients in a randomized, prospective trial. Methods and results: Four hundred consecutive patients ≥75 years with known or suspected coronary artery disease were included in the study. After exclusion of 93 patients with contraindications to the radial approach, 152 patients were randomized to the TR and 155 to TF coronary angiography and intervention. In 13 patients randomized to TR, cross‐over to TF was necessary (9%). Total examination time was significantly longer for the TR approach (18.1 vs. 15.0 min, P = 0.009), but no difference was found for fluoroscopy time, number of catheters used, or amount of contrast agent. The rate of major complications (bleeding requiring surgery or transfusion, stroke) was 0% for TR and 3.2% for TF approach (P < 0.001). Minor complications occurred in 1.3% versus 5.8% of patients (P < 0.001). Conclusion: In elderly patients, TR coronary angiography and intervention has a high technical success rate and lower complication rates than the TF approach. © 2008 Wiley‐Liss, Inc.