A Simple Approach for the Reduction of Knotted Coronary Catheter in the Radial Artery During the Transradial Approach

ABSTRACT: Development of a catheter knot is uncommon but still a matter of concern for a catheterizing cardiologist. There are only a few case reports of percutaneous catheter unknotting in the literature. We describe for the first time a case of catheter unknotting in a radial artery using a simple technique via the transradial approach. We concluded that percutaneous catheter unknotting in a radial artery using basic and simple hardware is a good alternative option to surgical management.

J INVASIVE CARDIOL 2011;23:E126–E127

Key words: catheter knot, complication, transradial approach

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Catheter knotting during coronary angiography is an uncommon but recognized complication.^1–8 It usually occurs through excessive manipulations of a catheter in an attempt to intubate the right coronary artery (RCA).^1,3 Despite being an important complication, there is little reported literature regarding its best management. Percutaneous transfemoral technique for catheter unknotting is already documented.^1–8 However, there is no mention in the literature for percutaneous transradial technique for the same complication. We describe a useful technique of catheter unknotting in the radial artery (RA) via the transradial approach (TRA) using simple hardware.

Case Report. A 75-year-old diabetic male patient with history of chronic stable angina was subjected to coronary angiography via right TRA. The ascending aorta was entered with difficulty because of significant subclavian tortuosity. Left coronary cannulation was done without difficulty using a 5 Fr Tig catheter (Terumo, Japan). However, while cannulating the RCA ostium, we encountered difficulty in catheter-tip movement despite several rotations. Suddenly, we noticed difficulty in contrast injection with simultaneous damping of pressure tracing on the monitor. Fluoroscopic examination along the catheter course revealed a tight knot of the catheter in the radial artery region (Figure 1A). We did several counter-clockwise rotations, but failed to reduce the knot. We tried to push a 0.035˝ standard guidewire through it to enlarge the knot diameter without success. We could not apply force with the guidewire because of the risk of perforating the catheter and RA. We then tried to fix the catheter distal to the knot by applying manual pressure on the brachial artery region in an attempt to reduce the knot by giving counter-clockwise rotation, but could not succeed. Because of significant subcutaneous fat in the cubital fossa, the catheter portion distal to the knot could not be fixed adequately, and while rotating the proximal end, the distal end also rotated counter-clockwise. Lastly, we applied the sphygmomanometer cuff in the brachial region and raised the cuff pressure up to 200 mmHg and successfully fixed the catheter distal to the knot. We could reduce the knot by giving several counter-clockwise rotations to the proximal portion (Figures 1B and 1C). We deflated the pressure cuff and removed the catheter. RA angiogram revealed no injury and normal radial artery (Figure 1D).

Discussion. Knotting of RCA catheter during the transfemoral approach (TFA) is a recognized complication and has been previously reported.¹ It is usually the result of excessive torquing of the RCA catheter, especially in the setting of a tortuous aorto-iliac system.

We offer the first description of a simple technique to unknot a catheter in the radial artery. The knot developed because of excessive clockwise rotations of the catheter in order to intubate the RCA ostium. Significant subclavian tortuosity was possibly instrumental for significant resistance and loss of one-to-one torque, leading to excessive rotations of catheter and development of a tight knot in the RA region. We tried several options of unknotting the catheter. We first tried to advance a 0.035˝ standard guidewire across the knot; however, we did not successfully pass it through and open the knot because the knot was too tight. There is always the risk of perforating a catheter and RA if excessive force is applied. Different techniques of catheter knot reduction have been described. There is one published case report suggesting the use of a longer introducer sheath to facilitate manipulation of a kinked catheter.³ Chinician et al described a technique that involved the introduction of a second catheter through the contralateral femoral artery. The second catheter was passed alongside the knotted catheter and directed through the loop of the knot. The knot was then pulled back to the bifurcation of the aorta and moved gently to and fro, enabling its reduction.⁵ This technique is difficult to apply for reducing the knot in an RA in view of its small caliber and also challenging anatomy while working from the contralateral radial route. Unfortunately, the above-mentioned techniques have their limitations in the form of dependence on significant knot laxity and bigger arterial lumen to work. Hence, there are higher chances of failure in cases of tighter knots and small arterial lumens.

Tanner et al described a knot reduction by fixing the catheter distal to the knot using the W grabber device from the contralateral femoral route.¹ Once the catheter was fixed in the segment distal to the knot, simple counter-clockwise rotation from outside was sufficient to unravel the knot. They reported a series of five cases and showed that fixing a knotted catheter distally obviated the need for passing the guidewire through the knot or passing another catheter through the loop. After unsuccessful initial attempts of counter-clockwise rotations and use of a guidewire to reduce the knot, we tried to fix the catheter distal to the knot by applying manual pressure over the brachial artery in the cubital region and attempted counter-clockwise rotation. We were unsuccessful because of inadequate fixation of the catheter segment distal to the knot due to fat in the cubital region. We then decided to apply the cuff of a sphygmomanometer in the brachial region and raised the cuff pressure up to 200 mmHg, which fixed the catheter segment distal to the knot and we could easily unknot the catheter by applying several counter-clockwise rotations under fluoroscopic guidance. This simple technique is easy to reproduce and also obviates the need for complex instrumentation as well as surgical intervention in the small-caliber RA.

References

1. Tanner MA, Ward D. Percutaneous technique for the reduction of knotted coronary catheters. Heart 2003;89:1132–1133.
2. Thomas HA, Sievers RE. Non-surgical reduction of arterial knots. Am J Roentgenol 1979;132:1018–1019.
3. Patel R, Kumar S, Hameedi S. Nonsurgical removal of a kinked right coronary catheter. Angiology 1984;35:601–603.
4. Bierman HR. On the intravascular knotting of catheters. Vasc Surg 1972;6:155–158.
5. Chinician A, Liebeskind A, Zingesser LH, et al. Knotting of an 8-French “headhunter” catheter and its successful removal. Radiology 1972;109:469–470.
6. Cohen HR, Deutsch AM, Ryvicker MJ, et al. Reduction of catheter knots. Radiology 1980;134:243–245.
7. Cho SR, Tisnado J, Beachley MC, et al. Percutaneous unknotting of intravascular catheters and retrieval of catheter fragments. Am J Roentgenol 1983;141:397–402. 
8. Rahim SA, Franke R, Mathew V. Removal of a knotted Swan-Ganz catheter. J Am Coll Cardiol 2009;53:E91.

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From ¹Total Cardiovascular Solutions Private Limited, Ahmedabad, India, ²the Department of Cardiology, Sheth V.S. General Hospital, Ahmedabad-380 006, India, and ³the Commonwealth Medical College, Scranton, Pennsylvania.
The authors report no conflicts of interest regarding the content herein.
Manuscript submitted September 15, 2010, provisional acceptance given October 12, 2010, final version accepted October 22, 2010.
Address for correspondence: Tejas Patel, MD, FACC, FSCAI, FESC, Professor and Head, Department of Cardiology, NHL Municipal Medical College, Sheth V.S. General Hospital, Ahmedabad-380 006, India. Email: tejaspatel@tcvsgroup.org