(A) Jacky Optitorque catheter (Terumo Interventional Systems) and (B) the Sarah radial Optitorque catheter (Terumo Interventional Systems). (Color version of fi gure is available online.) 

Context in source publication

Context 1

... nearing dialysis who may depend on the radial artery for access. Another minor drawback related to TRA is that intra- procedural cone beam computerized tomography (CT) may be technically more challenging to obtain as compared with TFA. However, cone beam CT acquisition during TRA is possible (Fig. 2), and new imaging protocols are in development to facilitate this technique. For interventional procedures below the diaphragm, such as hepatic embolization, left radial artery access is preferred over right-sided access for several reasons. There is a slightly shorter distance to the target vessel from the left wrist, which can be crucial given the current limitations of catheter lengths (discussed subsequently in detail). In addition, the guiding catheter or sheath is not positioned across the great vessels during the procedure, theoretically limiting the risk of cerebral emboli or thrombus formation. The patient ' s arm can be positioned in several ways. One option is to position the arm at 75o-90o, almost perpen- dicular to the table (Fig. 3). This allows for easier access to the vessel but makes catheter exchanges somewhat awk- ward and cumbersome. We prefer to position the arm at the patient ' s side in a similar position to that of the patient ' s groin. This allows for catheters or wires to be positioned over the patient ' s draped body similar to TFA (Figs. 4A and B). Arm positioning boards can also be used, and there are several such options available in the market today. The wrist should be slightly hyperextended, and a towel roll is used to support the wrist (Fig. 3). Prone positioning has also been described, allowing the left radial artery to be accessed and positioned in a similar fashion to those of the right common femoral artery. 14 This technique can be used in patients with chronic back pain who are unable to lie supine. The pulse oximeter is always placed on the thumb or fore fi nger of the wrist being accessed. The PRE-DILATE protocol, which entails topical application of 30 mg of nitroglycerin ointment and 40 mg of lidocaine cream to the radial artery access site 30 minutes before catheterization, signi fi cantly increases radial artery cross-sectional area, with the lidocaine also serving as a local anesthetic. 15 Our laboratory uses EMLA cream (lidocaine 2.5% and prilocaine 2.5%) in place of pure lidocaine cream. In our laboratory, radial artery access is obtained using ultrasound guidance and the Seldinger technique with a 21-gauge echogenic-tip needle (Fig. 4C). Other laborato- ries use the “ angiocath technique. ” A small intra venous catheter is advanced through both walls of the radial artery under direct palpation and slowly pulled back until blood fl ow is seen. A 0.018-in wire is advanced into the radial artery (Fig. 4D). If there is any resistance, the wire is pulled back and readjusted. If the wire cannot be advanced, fl uoroscopy and direct visualization with contrast is performed. A specialized radial access sheath with a hydrophilic coating is then used. The dilators on these sheaths are tapered to 0.018 in to allow for immediate sheath placement without an incision or wire exchange. The most common hydrophilic sheath used in our laboratory is the 10-cm length Glidesheath (Terumo Interventional Systems, Somerset, NJ) (Fig. 5A). Other commonly used hydrophilic radial sheaths include PreludeEASE (Merit Medical Systems, Inc, South Jordan, UT) and Flexor Radial Introducer (Cook Medical, Inc, Bloomington, IN). Rathore et al 16 showed that the use of hydrophilic sheaths decreases the incidence of radial artery spasm and pain during TRA. Most of the diagnostic and interventional procedures can be performed with 5- to 6-F sheaths; however, safe radial access can be performed with sheaths ranging in size from 4-7 F. The Glidesheath Slender (Terumo Interventional Systems) is a radial sheath with a very thin wall, providing a 6-F lumen while maintaining an outer diameter matching that of a 5-F sheath (Fig. 5B). In a prospective feasibility study enrolling 114 patients, Aminian et al 17 demonstrated greater than 99% technical success using the Glidesheath Slender with no major sheath kinking and a radial artery occlusion rate less than 1% at 30-day follow-up. Table 1 lists several radial artery access sheaths presently in the market. After sheath placement, a medication “ cocktail ” is administered intra-arterially directly though the access sheath. Nitrates, calcium channel blockers, and heparin are typically used to prevent arterial spasm and reduce vascular tone. Although there are numerous recommen- dations, there is no consensus on the ideal mixture. Our laboratory uses 3000 IU of heparin, 200 m g of nitroglycerin, and 2.5 mg of verapamil. It is important to note that verapamil causes a signi fi cant burning sensation upon injection, so continual hemodilution and slow injection is recommended (Fig. 6). In most cases, a 110-cm Jacky Radial or Sarah Radial Optitorque catheter (Fig. 7) (Terumo) and a standard 0.035-in access wire are used to navigate the subclavian region and engage the descending aorta. The catheter is then “ hubbed ” in the sheath, and small aliquots of contrast are used as the catheter is pulled back to engage the superior mesenteric artery and celiac artery. Other catheters that may be used for subdiaphragmatic intervention include the Merit Ultimate catheters (Merit Medical Systems, Inc, South Jordan, UT). In addition to the unique shape of these catheters, the 110-cm length makes them very useful in taller patients where 100 cm is not adequate. One of the major limitations of TRA for hepatic embolization is the limited availability of unique shapes and lengths for engaging the mesenteric vessels. Efforts are currently underway to design new catheters for this purpose. For hepatic embolization procedures, standard- length microcatheters (130 and 150 cm) are then used to select the appropriate hepatic artery for treatment purposes. In general, 150-cm length microcatheters are recommended when using diagnostic catheters that are longer than 100 cm, particularly if Tuohy-Borst adapters are being used. In our practice, TRA is most commonly used in transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) in both the macroaggregated albumin mapping procedures and delivery of yttrium-90. In 2003, TACE using TRA was fi rst described in Japan. 18 Shiozawa et al retrospectively compared 150 TACE patients who underwent TFA and 177 patients who underwent TRA. Of the 70 patients who received both approaches, 92.9% preferred TRA. Although unpublished, our data using the TRA approach currently suggest the same trend. Uterine fi broid embolization may also be safely performed using TRA. In a retrospective study examining transradial uterine fi broid embolization in 29 patients, 100% technical success was achieved using a 4-F 120-cm Glidecath (Terumo), with additional use of a microcatheter required in 12 cases for cannulation of the horizontal segment of the uterine arteries. No major or minor complications were experienced, and there were no cases of radial artery occlusion at 1-month follow-up. 19 Imaging evaluation and intervention planning now include a complete vascular evaluation with CT angiography or magnetic resonance angiography of the hepatic vasculature. The angle of the access artery (celiac or superior mesenteric) to the aorta as well as the vascular tortuosity (iliac or aortic arch) is taken into account when planning TRA or TFA. Dif fi cult access cases can be triaged to a single technique based on the perceived dif fi culty of vascular access. For complex mesenteric, renal, and iliac interventions, 5- and 6-F guide catheters are used for balloon angioplasty, intravascular ultrasound, and stent placement. The Launcher coronary guide catheter (Med- tronic, Inc, Minneapolis, MN) and the Runway guiding catheter (Boston Scienti fi c Corporation, Natick, MA) are most commonly used. These are available in different catheter tip shapes and multiple lengths, including 100, 110, 118, and 125 cm. Nonocclusive “ patent ” hemostasis is a key technique in minimizing risk of postprocedural radial artery thrombosis. The prevention of radial artery occlusion- patent hemostasis evaluation trial (PROPHET) study in 2008 demonstrated that this technique is superior to occlusive pressure in maintaining radial artery patency. 20 Nonocclusive hemostasis is typically performed using a wrist band device. There are several such devices in the market today, which are listed in Table 2. The most common device used in our laboratory is the TR Band (Terumo Interventional Systems) (Fig. 8). A distal radial artery pulse should be palpable during the hemostasis period, which ranges from 30-120 minutes, depending on the complexity of the procedure performed. After a typical TACE or TARE procedure using a 5-F access sheath, the band is slowly de fl ated in 15 minutes after 75-90 minutes of patent hemostasis. If bleeding or “ oozing ” is seen from the puncture site during the removal process, the band is rein fl ated for 20 minutes, and the process is repeated. Once the band is successfully removed, the patient is observed for 30 minutes before discharge. The most common, albeit rare, complication seen in our practice is a localized minor hematoma (grade 1) with mild pain at the access site. This is often self-limited and can be treated with nonsteroidal anti-in fl ammatory drugs if nec- essary. Despite proper patent hemostasis technique, radial artery thrombosis will occur in a minority of cases, which are almost always asymptomatic. 21 Factors associated with a decreased rate of radial artery occlusion include increased heparin dose, smaller sheath size, and use of a hydrophilic sheath. 20 Other rare complications include radial artery pseudoaneurysm, perforation, radial arteritis, severe spasm, and dissection. Digital ischemia is exceedingly rare and has been ...