Design and testing of a high-flow autoperfusion catheter: an experimental study.

An autoperfusion catheter is similar to an angioplasty balloon catheter with side holes in the guide-wire lumen proximal to the balloon. When the balloon of the autoperfusion catheter is deployed and inflated in an artery, the guide wire is removed, and the hub of the guide-wire lumen is capped. The catheter then allows passive distal perfusion by using ambient pressure to drive blood into the guide-wire lumen, through the balloon, and out the end hole. This article discusses the requirements and constraints of a high-flow autoperfusion catheter, summarizes attempts to modify standard angioplasty catheters for use as an autoperfusion catheter, and describes the design and testing of a custom autoperfusion catheter capable of delivering approximately 3 mL/sec at physiologic pressures. In a model of canine acute renal artery occlusion lasting 90 minutes, the custom autoperfusion catheter provided marked protection from acute tubular necrosis compared with conventional percutaneous transluminal angioplasty catheters. The authors conclude that the high-flow autoperfusion catheter may be useful as a temporary stent in cases of rupture, dissection, or penetrating wounds involving large arteries.     

Autoperfused balloon catheter for intravascular MR imaging

An intravascular magnetic resonance (MR) imaging catheter for high-resolution imaging of vessel walls was developed. The catheter design is based on an autoperfusion balloon catheter that allows passive perfusion of blood during balloon inflation. The blood enters a central lumen through multiple sideholes of the catheter shaft proximal to the balloon. A remotely tuned, matched, and actively decoupled, expandable single-loop radiofrequency coil was mounted onto the balloon to receive intravascular MR signals. The autoperfusion rate through the catheter was determined experimentally relative to perfusion pressure. The catheter concept was evaluated in vitro on human femoral artery specimens and in vivo in the internal carotid artery of two pigs. The proposed catheter design allowed for maintained blood perfusion during the acquisition of high-resolution intravascular images. During perfusion, image quality remained unaffected by flow, motion, and pulsatility artifacts. The availability of an autoperfused intravascular catheter design can be considered an important step toward high-resolution atherosclerotic plaque imaging in critical vessels such as the carotid and coronary arteries.     

Residual stenosis after conventional balloon angioplasty for hemodialysis shunt failure: treatment with metallic stent placement and post-balloon dilatation

PURPOSE: The usefulness of metallic stent placement and post-balloon dilatation was investigated for patients with residual stenosis after conventional percutaneous transluminal balloon angioplasty (balloon PTA) of dialysis shunt vessels. MATERIALS AND METHODS: Among 92 patients who had received balloon PTA for dialysis shunt vessels, seven patients who showed a residual waist on the balloon even under maximum inflation were enrolled in this study. In these patients with residual stenosis after balloon PTA, we inserted a stent in the residual stenosis, and post-balloon dilatation was immediately applied using the same balloon catheter. RESULTS: After balloon PTA, the average percent diameter stenosis declined to 45.5 +/- 7.30%, and the stenosis was further improved to an average of 19.3 +/- 7.09% after the placement of a stent and the additional balloon PTA. The average percent diameter dilatation of the balloon before the placement of a stent was 65.8 +/- 12.7%, while the average dilatation increased to 84.1 +/- 8.96% after the placement of a stent. Dialysis became possible immediately after the procedure in all cases. CONCLUSION: Metallic stent placement and post-balloon dilatation was effective for patients with residual stenosis after conventional balloon PTA of dialysis shunt vessels.     

Percutaneous transluminal angioplasty: general principles

The introduction and availability of balloon catheters has been responsible for the recent popularity of percutaneous transluminal angioplasty (PTA) in the United States. Available balloon catheters are either double-lumen or coaxial systems. Most balloons are made of polyvinyl but one manufacturer has produced an angioplasty catheter made of specially treated polyethylene, which exhibits higher tensile and yield strength in comparison to polyvinyl. Automatic pressure injectors are necessary for the coaxial balloon system. They are not used with single catheters and larger balloons. Devices monitoring balloon inflation pressures are now available and they should be used. There is no consensus on the use of anticoagulant therapy in conjunction with PTA. Complications of PTA are few and easy to manage. Noninvasive hemodynamic studies (Doppler and pulse volume recordings) are necessary during PTA and for evaluation of long-term patency. PTA should be performed by experienced angiographers in hospitals with adequate angiographic and vascular surgical facilities. Decisions about PTA and subsequent patient management are best made in consultation with the patient's primary physician, a vascular radiologist, and a vascular surgeon.     

膝下动脉球囊成形术及溶栓介入治疗糖尿病足的价值(附19例分析)

目的:探讨膝下动脉球囊成形术及保留导管溶栓术在介入治疗糖尿病足的临床价值。方法:对19例糖尿病足患者介入术前行CTA检查,对31个下肢用Seldinger技术,经股动脉顺行穿刺插管,分别对膝下动脉病变采用经血管腔内球囊成形术、保留导管溶栓术等多种介入治疗方法。结果:介入治疗后患肢血流改善明显,狭窄性病变开通率明显大于闭塞性病变。皮温明显升高,行走距离显著增加,溃疡愈合加快。结论:膝下动脉球囊成形术及保留导管溶栓治疗微创、安全、有效,可以改善糖尿病足下肢动脉血供,近期疗效令人满意。     

彩色多普勒超声引导下经皮气囊导管成形术治疗Budd-Chiari综合征

目的探讨彩色多普勒超声（ＣＤＵ）引导经皮气囊导管成形术（ＰＴＡ）治疗ＢｕｄｄＣｈｉａｒｉ综合征（ＢＣＳ）的可行性及临床实用价值。方法ＢＣＳ患者９例。其中下腔静脉膜型闭塞５例，节段型闭塞２例和狭窄１例；右肝静脉闭塞１例。在ＣＤＵ的引导和监视下，经右股静脉分别对上述患者静脉狭窄或闭塞段进行穿刺和气囊扩张，并根据静脉内径、血流方向及频谱形态决定扩张程度。结果ＣＤＵ可清晰显示导管、导丝、穿刺针及气囊导管在血管中的位置，正确引导术者进行ＰＴＡ治疗，技术成功率１００％；血管形态和血流动力学是判断ＰＴＡ治疗效果的可靠指标。结论ＣＤＵ是一种引导ＰＴＡ治疗ＢＣＳ的安全、可靠方法     

Carotid endarterectomy and simultaneous percutaneous transluminal angioplasty for tandem internal carotid stenoses

We treated three patients with tandem internal carotid stenoses in single procedures including carotid endarterectomy (CEA) for the proximal stenosis and percutaneous transluminal angioplasty (PTA) for the distal stenosis. We devised a Y-shaped shunt tube for the CEA, through which a balloon catheter was introduced to perform PTA guided by mobile digital subtraction angiography. No cerebrovascular events occurred during follow-up. Our approach avoids the risk of a second procedure while effectively treating tandem stenoses. Received: 20 August 1997 Accepted: 5 November 1997     

A comparison study of self-expandable stents vs balloon angioplasty alone in femoropopliteal artery occlusions

In a group of 26 patients percutaneous transluminal (balloon) angioplasty (PTA) and stents (Wallstents) were applied and in another 26 matched patients PTA alone was used as primary treatment for femoropopliteal occlusions of 3 cm or longer. Five patients with stents showed early thrombosis necessitating catheter thrombolysis and/or thrombus aspiration. Ten patients had recurrent stenoses within 12 months, mostly due to neointimal hyperplasia. Following three late catheter reinterventions, a cumulative secondary patency rate of 69% was achieved after 12 months. The group of patients treated by PTA alone showed a 12 months patency rate of 65% without reinterventions. In 8 other patients, stents were inserted for recurrent obstructive or PTA-resistant lesions, and similar results as with the stents above were obtained. Thus, these stents do not improve primary results of PTA in femoropopliteal occlusions but may be useful secondarily after unsuccessful PTA.     

Vascular rupture complicating transluminal angioplasty applied on a failed dialysis vascular access in a patient under chronic steroid therapy

We report a case of venous rupture complicating percutaneous transluminal angioplasty (PTA) applied on a failed dialysis vascular access (VA) in a patient on chronic steroid therapy. This complication resulted in a rapidly growing hematoma which was successfully controlled by a prolonged reinflation of the balloon catheter at the angioplasty site. The absence of oversizing of the balloon catheter and the low inflation pressure at which the perforation occurred suggest a vessel fragility which was probably induced by a long-standing steroid therapy. In dialysis patients in whom steroid therapy does not represent an infrequent therapeutic modality, this potential risk of vascular rupture should be carefully weighted while treating VA stenoses with the use of PTA. Received 10 January 1996; Revision received 18 March 1996; Accepted 23 July 1996     

Percutaneous transluminal angioplasty: development, technique, and application

Percutaneous transluminal angioplasty (PTA) is one of the most exciting developments in the field of interventional radiology. In this procedure an angiographic catheter with an inflatable balloon is used to reopen the lumen of an artery that was previously obstructed due to plaque formation. This article describes the historical development of PTA, the technique involved in catheter angioplasty, and its application in certain disease states.     

Renal angioplasty: Experiences with 94 patients

Percutaneous transluminal angioplasty (PTA) was performed on 94 patients with hypertension due to renovascular stenosis. In 76 cases PTA was successful. Even in the presence of severe arteriosclerosis the balloon catheter technique was successful and resulted in few complications. Recording intraluminal blood pressure is the best parameter to predict a successful outcome. Nuclear studies are helpful in the follow-up of patients. The principal aim of PTA is to lower the blood pressure and to salvage the diseased kidney.     

Direct percutaneous transluminal angioplasty for acute middle cerebral artery occlusion.

PURPOSEWe review our initial experience with direct percutaneous transluminal angioplasty (PTA) as a reperfusion treatment for acute occlusion of the middle cerebral artery.METHODSTen patients in whom successful thrombolysis might not be expected because of the risk of hemorrhagic complications or reocclusion were treated with direct PTA. When early ischemic findings were present on the initial CT scans and/or when lenticulostriate arteries were involved, we performed direct PTA rather than thrombolytic therapy. Direct PTA was also performed when superselective local angiography via a Tracker catheter advanced just distal to the occlusion site showed the presence of a large embolus or high-grade stenosis suggestive of thrombosis. Angioplasty was performed with a Stealth balloon catheter with a maximum diameter of 2.0 to 2.5 mm. The balloon catheter was advanced into the site of occlusion and inflated to 2 atm initially, and subsequently up to 3 atm. Two to six inflations, each of 30 seconds'' duration, were performed.RESULTSAlthough the rate of initial recanalization was 100% (10 of 10), reocclusion occurred in two patients with atherothrombotic M2 occlusion. The final angiographic success rate of direct PTA was 80% (8 of 10). There were no hemorrhagic or technical complications, and five of 10 patients showed marked clinical improvement. In two of seven patients with cardioembolic M1 trunk occlusion, crushed fragments of the embolus obstructed M2 portions after direct PTA, necessitating local thrombolysis.CONCLUSIONDirect PTA may be performed safely as an alternative to thrombolytic therapy in patients with acute occlusion of the middle cerebral artery when early CT findings and/or lenticulostriate artery involvement are present or when superselective local angiography shows the presence of a large embolus or high-grade stenosis.     

大动脉炎颈动脉狭窄球囊扩张和内支架的治疗

目的：探讨应用球囊扩张和血管内支架治疗大支脉炎、颈动脉狭窄、材料和方法：３例大动脉炎性颈动脉狭窄的患者，狭窄段均超过８ｃｍ，１例单纯球囊扩张；２例球囊扩张后植入Ｗａｌｌｓｔｅｎｔ支架。结果：术后狭窄率均为０，达到了良好的治疗效果，单纯球囊扩张的动脉一年后动脉完全闭塞、西入血管内支架的２例，分别是在４．５个月和４个月检查，一例血管内支架的近端出现了再狭窄，另一例未出现再狭窄。结论：对于大动脉炎性长段     

MR-guided percutaneous angioplasty: Assessment of tracking safety, catheter handling and functionality

Purpose: Magnetic resonance (MR)-guided percutaneous vascular interventions have evolved to a practical possibility with the advent of open-configuration MR systems and real-time tracking techniques. The purpose of this study was to assess an MR-tracking percutaneous transluminal angioplasty (PTA) catheter with regard to its safety profile and functionality. Methods: Real-time, biplanar tracking of the PTA catheter was made possible by incorporating a small radiofrequency (RF) coil in the catheter tip and connecting it to a coaxial cable embedded in the catheter wall. To evaluate potentially hazardous thermal effects due to the incorporation of the coil, temperature measurements were performed within and around the coil under various scanning and tracking conditions at 1.5 Tesla (T). Catheter force transmission and balloon-burst pressure of the MR-tracking PTA catheter were compared with those of a standard PTA catheter. The dilatative capability of the angioplasty balloon was assessed in vitro as well as in vivo, in an isolated femoral artery segment in a swine. Results: The degree of heating at the RF coil was directly proportional to the power of the RF pulses. Heating was negligible with MR tracking, conventional spin-echo and low-flip gradient-echo sequences. Sequences with higher duty cycles, such as fast spin echo, produced harmful heating effects. Force transmission of the MR-tracking PTA catheter was slightly inferior to that of the standard PTA catheter, while balloon-burst pressures were similar to those of conventional catheters. The MR-tracking PTA catheter functioned well both in vitro and in vivo. Conclusion: The in vivo use of an MR-tracking PTA catheter is safe under most scanning conditions.     

腔静脉异常引流（附二例报告）

报告二例下腔静脉闭塞伴有侧支循环血管引渡以下腔静脉血液进入左心房。临床表现为口唇紫绀、杵状指和门脉和下腔静脉高压的症状和体征。采用经皮穿刺下腔静脉球囊扩张术使下腔静脉再通后，血氧饱和度和血氧分压升高至正常，门脉和下腔静脉高压的症状和体征消失，术后多普勒超声于引流血管内无血流频谱发现。     

Arterial occlusive disease below the knee: treatment with percutaneous transluminal angioplasty performed with low-profile catheters and steerable guide wires

In 98 patients with arterial occlusive disease below the knee who were candidates for limb salvage surgery, percutaneous transluminal angioplasty (PTA) was performed with a low-profile balloon catheter and steerable guide wire system. Sixteen patients had bilateral disease; thus, there were 114 endangered limbs and 145 diseased vessels, including 19 with a single stenosis, 94 with multiple stenoses, and 32 with total occlusions. Primary anatomic success was achieved in all stenosed vessels and in 28 occluded vessels. Initial limb healing without amputation was achieved in 88% of limbs. In four patients occluded vessels could not be recanalized; thus, the four affected limbs were amputated. Two years after PTA, 32 of 37 patients available for follow-up had viable pain-free extremities. Cumulative limb salvage rate at 2 years was 86%. At this time, below-the-knee PTA is still recommended only for limb salvage candidates. However, with this new catheter and guide wire system, success rates have been increased and complication rates decreased. PTA may be useful in selected patients with severe claudication.     

Percutaneous transluminal angioplasty (PTA) with the Grüntzig balloon catheter: Technical problems encountered in the first forty patients

Forty patients have undergone percutaneous transluminal angioplasty (PTA) of the iliac or femoral-popliteal system with the Grüntzig balloon catheter. Technical problems have included experience with difficult antegrade puncture, production of intimal flaps, and loss of collateral vessels, as well as the need to develop an approach for recanalization of obstructions and for use of the balloon. Since problems in these areas may jeopardize the success of the procedure, they have been elucidated with some discussion of prevention. Preliminary results on the success of the procedure are included.     

Failure of prolonged dilation to improve long-term patency of femoropopliteal artery angioplasty: results of a prospective trial

PURPOSE: To determine long-term patency of femoropopliteal artery percutaneous transluminal angioplasty (PTA) in a prospective trial during which prolonged balloon inflation was used for optimization of initial results. MATERIALS AND METHODS: Femoropopliteal PTA was performed in 112 limbs of 97 patients. The mean total length of the treated segments was 7.2 cm (95% CI: 5.99-8.46; median: 5.5 cm). In cases of unsatisfactory primary results after standard dilation for 1-3 minutes, the procedure was continued with prolonged dilation (93 limbs; mean balloon inflation time: 31 min; 95% CI: 24.2-37.7; median: 15 min) with use of the same balloon catheter (77 limbs) or a perfusion balloon catheter (35 limbs). Thirty-four proximal infrapopliteal artery stenoses were treated to improve peripheral runoff and 12 short stents were placed because of flow-limiting dissections. RESULTS: Primary hemodynamic success established by Doppler ultrasound (US) criteria was achieved in 92.9% (104 of 112) of the limbs. Three major complications were encountered; none were related to prolonged balloon inflation. The primary patency rate according to Kaplan-Meier analysis was 42% (+/-5% SE) at 1 year and 39% (+/-5%) at 2 and 3 years. The corresponding secondary patency rates were 51% (+/-5%) and 47% (+/-5%). Large numbers of diseased vessels in the treated limb (four to 10 instead of one to three), eccentric lesions (as opposed to concentric morphology), and additional treated segments (instead of only femoropopliteal lesions) were associated with poorer long-term patency. The duration of balloon dilation was not a determinant of long-term patency. CONCLUSION: Although prolonged dilation is safe and feasible in femoropopliteal artery PTA, its routine use is not warranted because it does not result in superior long-term patency rates.     

Dilatation of the supra-aortic arteries--a catheter with blockade and rinsing potential

Percutaneous transluminal angioplasty (PTA) of supra-aortic arteries is not generally accepted, mainly because of the fear of brain embolism. The design of a new catheter offers four conduits and permits (1) guidewire conduct, (2) tip occlusion; (3) PTA; and (4) rinsing between occluded tip and dilational balloon. Thus, any particles that might otherwise cause brain embolism could be washed out after PTA and before opening of the tip occlusion. The prototype has already been manufactured. The catheter is easy to handle.     

血管内介入治疗在膝下动脉闭塞性病变中的临床应用

目的:评价膝下动脉闭塞性病变血管内介入治疗的临床效果和必要性。方法:回顾性分析2005年4月～2007年12月间收治的42例(47条肢体)采用球囊血管成形术治疗的以膝下动脉病变为主的动脉硬化闭塞症患者的临床资料。结果:42例患者的43条肢体闭塞病变治疗获得成功,成功率为91.5%(43/47),术后平均随访5月(1～10月),临床症状明显改善;1例介入治疗后1月行膝下截肢术,截肢率为2.1%。结论:球囊血管成形术治疗下肢动脉硬化闭塞性疾病的膝下动脉病变可行性强、疗效显著、安全性良好,近期疗效确切,长期疗效还需进一步随访研究。