Guide catheters

The Concentric Retriever (Concentric Medical Inc., Mountain View, CA), a flexible, nitinol wire with helical tapering coil loops (X5 and X6) that is used in conjunction with a balloon guide catheter (8 or 9 French) and a microcatheter, is the only device currently approved by the FDA for the endovascular treatment of stroke patients (Fig. 4.3). The second-generation devices (L5 and L6) differ from the X devices by the inclusion of a system of arcading filaments attached to a nontapering... 

Suction thrombectomy or thromboaspiration through either a microcatheter or a guiding catheter may be an option for fresh nonadhesive clot. As discussed above, aspiration devices have the advantage of causing less embolic events and vasospasm however, the more complex design of these devices makes them more difficult to navigate into the intracranial circulation. 

The Penumbra stroke system (Penumbra Inc., San Leandro, CA) includes two different revascularization options (1) thrombus debulking and aspiration may be achieved by a reperfusion catheter that aspirates the clot while a separator device fragments it, and (2) direct thrombus extraction may be performed by a ring retriever while a balloon guide catheter is used to temporarily arrest flow. This system has been tested in a pilot trial in Europe. Twenty patients (mean NIHSS 21) with a total of 21 vessel occlusions (7 ICA, 5 MCA, and 9 Basilar) were treated up to 8 hours after symptom onset. Recanalization prior to lA lysis was achieved in all cases (48% TIMI 2 52% TIMI 3). Seven patients were also treated with lA UK or rt-PA. Good outcome at 30 days (defined as mRS < 2 or NIHSS 4-point improvement) was demonstrated in 42%. The mortality rate was 45%, but there were no device-related deaths. There was one asymptomatic SAH and three symptomatic ICHs. A prospective, single-arm, multicenter trial is being conducted in the United States and Europe currently. 

Approach used for subselective infusion prior to attempted PCI of a RCA. Left) The RCA has been intubated with a guiding catheter, and a small infusion catheter advanced to the beginning of the occlusion. (Right) Both guide catheter and infusion catheter are used to deliver material. Both must be secured to avoid displacement. Ostial occlusion lesions are not suitable for this approach. 

Solitaire device black arrow, distal markers white arrow, balloon guide catheter), (e) Photograph of the Solitaire device black arrow) and the retrieved thrombi, (f) Posttreatment angiogram demonstrates near complete reperfusion (TICl 2b) of the right ICA territory after treatment with the Solitaire device and adjunctive intra-arterial rt-PA infusion. Courtesy of Dr. Vitor M. Pereira, Geneva University Hospital, Switzerland... 

The ReviveFlow system (ReviveFlow, Inc., Quincy, MA) is a novel method of cerebral flow reversal in which a balloon guide catheter is placed in the cervical internal carotid arteries and jugular veins on one or both sides of the neck. The balloons are subsequently inflated and blood is aspirated via an external pump system from the proximal 1C A and infused in the distal internal jugular vein. The end result is total reversal of the cerebral circulation and perfusion of the venous system with arterial blood into the capillary bed, which is now physiologically proximal to the occluded artery. This device is currently undergoing precliifical smdies. 

Intracardiac echocardiography is emerging as an ideal real-time modality to guide intracardiac interventional procedures. ICE allows accurate appreciation of cardiac anatomy and detailed visualization of specific anatomic structures, the most important factors in planning and guiding catheter-based interventional techniques [15-17]. In our daily practice, ICE is performed using a commercially available 9-F/9 MHz ultra-ICE catheter-based ultrasound transducer (EP Technologies, Boston Scientific, San Jose, CA, USA). The Ultra ICE catheter is introduced percutaneously into the... 

Cross sectional occlusion of the artery/vein is easily produced when coaxial catheters were used. The elongation of pushable fibered coils is avoided by advancing the coil through the inner 4- or 5-F catheter while holding the outer guide catheter stable in the artery or vein (Fig. 3.3). In this way the soft... 

Fig.3.5. The anchor technique. This technique is very valuable for providing safe and distal occlusion when there is a question about instability of pushable fibered coils. Diagrammatically, the guide catheter is placed in the artery to be occluded and a 5-F inner catheter or microcatheter is advanced into a side branch next to the site requiring occlusion. At least 2 cm of a 14-cm standard Nester or Micronester are advanced into the side branch which is normally sacrificed. The rest of the coil is then deployed just proximal to that side branch and additional coils are packed so that cross-sectional occlusion is obtained...

Integral to using pushable fibered coils to produce cross sectional occlusion is the use of coaxial or tri-axial guide catheter systems. For venous occlusions (varicocele and/or pelvic congestion) or occlusions of PAVMs, we use standard 7/5 combinations (Pulmonary, Cook) or gonadal (Cordis Inc., Miami FL) with inner 5-F endhole catheters (Fig. 3.9). 

Fig. 3.9a-d. A standard 7-F gonadal guide catheter for occlusion of the left spermatic or ovarian vein (Cordis Inc., Miami, FL) is demonstrated in (a) and in (b) the 7/5 pulmonary guiding catheter and inner catheter for occlusion of pulmonary arteriovenous malformations is shown. Once the ovarian or internal spermatic vein are catheterized, any standard 100-cm 5-F endhole multipurpose catheter is advanced over a Bentson wire deep into the spermatic or ovarian vein where sclerosants and coils are usually placed. A standard 6-F RDC (Cordis Inc., Miami, FL) guide catheter for visceral embolization is demonstrated with a coaxial 4-F catheter in (c) and in (d), a triaxial system is demonstrated with an inner 0.021 lumen microcatheter... 

For a transbrachial approach, also consider a vertebral or headhunter catheter we rarely use guiding catheters. For transbrachial approach. 

The most common cause for spasm is related to the catheterization. Careful catheterization is essential, although spasm can occur even in experienced hands. Use of a smaller catheter size (4 F) with hydrophilic coating and smaller hydrophilic guidewires (0.021 instead of0.035 ) may reduce the occurrence of spasm. Systematic usage of the microcatheter is now recommended. The guiding catheter is placed at the origin of the uterine artery or even in the internal iliac artery. However, even with the systematic use of a microcatheter, spasm was present in 31% of cases in a recent study by Spies et al [Ij. 

In our experience, use of vasodilators in the presence of spasm was not very helpful. When spasm occurs, the guiding catheter needs to be pulled out of uterine artery until the spasm is resolved. Sometimes the microcatheter should be pulled out of uterine artery as well. In cases of persistent spasm of the left uterine artery, one can remove the catheter and proceed to the embolization of the right uterine artery before re-catheterization of the left side. If a flow-limiting spasm persists, the use of smaller sized... 

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