Distal Anchoring Technique: Yet Another Weapon for Successful Intervention

The evolution of percutaneous coronary and peripheral interventions in terms of device profile, deliverability, and flexibility, and their proven long-term safety and benefit have extended their reach to more and more complex coronary and peripheral lesions including calcified and tortuous vessels, chronic total occlusions, and bifurcation lesions. In addition, there is growing interest in percutaneous intervention of chronic total occlusions in patients with continued ischemia despite maximal medical therapy, especially post CABG with a patent left internal mammary artery graft.^1,2 These lesions present several challenges limiting procedural success rates. A key factor for procedural failure remains the inability to deliver balloons and stents to the target lesion.³ Obviously, the choice of an appropriate guiding catheter with adequate support, appropriate guide wires, balloons, and stents are instrumental to ensuring success in such cases. Larger diameter guiding catheters properly shaped to provide adequate support using aortic wall as back-up, newer generation wires with hydrophilic coating and stiff shafts, buddy wire techniques, wiggle wires (Abbott Vascular, Santa Clara, California), rotational atherectomy (Boston Scientific Corp., Natick, Massachusetts), along with small profile balloons and stents have dramatically improved the success of even the most complex of procedures. Yet, we still encounter cases where all these measures may not be enough or appropriate. This is where more innovative techniques come into play. These include the use of a Guide Liner catheter (Vascular Solutions, Minneapolis, Minnesota), double coaxial guiding catheter (Mother-Child) technique and balloon anchoring technique.⁴ These techniques are useful in appropriate situations but also have potential associated complications. Careful selection and implementation of these advanced techniques are thus instrumental not only to improve procedural success but also to prevent complications.

The balloon anchoring technique, initially described by Fujita,⁵ has gained interest since and several case reports of its successful use in complex CTO cases have been published. It was initially described as a side branch anchor technique, i.e., inflation of balloon in a proximal side branch to improve guide support. Since then, two variations have been successfully used: the proximal coaxial balloon anchor to improve support for guidewire passage through the occlusion and the distal balloon anchor with balloon inflation at or distal to the lesion to improve support for deliverability of balloon and stents after the guidewire has already crossed the lesion.^{6, 7}

In this issue of the Journal, Mahmood et al⁸ have presented several examples of successful application of distal balloon anchor technique in complex coronary interventions and an example of successful delivery of a guiding sheath across a difficult aortic bifurcation. The use of the distal anchoring technique enabled them to complete these 5 difficult cases successfully; however, this should remain the option of last resort. A more aggressive guide could have been used in case 1, a 5 Fr sheath with hydrophilic coating or an antegrade or brachial artery stick could have been used in case 5. Nonetheless, the described cases help present different scenarios where this technique may be useful.

With more complex, tortuous, calcified, chronically occluded target vessels, it does seem that we need all available modalities to achieve a successful outcome in every intervention. Complex interventions are making us experts in fluid dynamics, motion physics, friction, and vectors and correct understanding of these parameters will enable the interventionalist to choose the appropriate equipment to use to maximize chances of success and use these advanced techniques if all else fails. However, all these techniques will likely result in damage to the vessel wall whether at site of inflation of distal anchoring balloon or side of deep seating of guiding catheter. These traumatic injuries will potentially cause endothelial denudation, intimal tears, and may result in atherosclerosis, neointimal proliferation, dissection, and plaque rupture. Therefore, for distal balloon anchoring, we do recommend using the shortest balloon available (6 mm) inflated at distal portion of the target lesion enabling delivery of the stent as close as possible to its intended location. In addition, all other techniques should be used before resorting to these techniques. Even if they increase the acute procedural success, larger series and studies with adequate long-term clinical and possibly angiographic follow-up are essential to establish the safety of these techniques.

Furthermore, it is important to emphasize that medical therapy remains the cornerstone of coronary artery disease and peripheral arterial disease treatment with interventions reserved for angina and claudication refractory to maximal medical therapy and for acute coronary syndromes and critical limb ischemia. “An quia potest non dicit ut: Just because we can does not mean that we should.”

References

1. Stone GW, Kandzari DE, Mehran R, Colombo A, Schwartz RS, Bailey S, et al. Percutaneous recanalization of chronically occluded coronary arteries: A consensus document: Part i. Circulation 2005;112:2364–2372.
2. Di Mario C, Werner GS, Sianos G, Galassi AR, Buttner J, Dudek D, et al. European perspective in the recanalisation of chronic total occlusions (CTO): Consensus document from the Euro CTO Club. EuroIntervention 2007;3:30–43.
3. Stone GW, Rutherford BD, McConahay DR, Johnson WL Jr, Giorgi LV, Ligon RW, Hartzler GO. Procedural outcome of angioplasty for total coronary artery occlusion: An analysis of 971 lesions in 905 patients. J Am Coll Cardiol 1990;15:849–856.
4. Di Mario C, Ramasami N. Techniques to enhance guide catheter support. Catheter Cardiovasc Interv 2008;72:505–512.
5. Fujita S, Tamai H, Kyo E, Kosuga K, Hata T, Okada M, et al. New technique for superior guiding catheter support during advancement of a balloon in coronary angioplasty: The anchor technique. Catheter Cardiovasc Interv 2003;59:482–488.
6. Hirokami M, Saito S, Muto H. Anchoring technique to improve guiding catheter support in coronary angioplasty of chronic total occlusions. Catheter Cardiovasc Interv 2006;67:366–371.
7. Hamood H, Makhoul N, Grenadir E, Kusniec F, Rosenschein U. Anchor wire technique improves device deliverability during PCI of CTOs and other complex subsets. Acute Card Care 2006;8:139–142.
8. Mahmood A, Banerjee S, Brilakis ES, et al. Applications of the distal anchoring technique in coronary and peripheral interventions. J Invasive Cardiol 2011;23:289–292.

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From the Division of Cardiology, Interventional Cardiology Section, BIDMC/Harvard Medical School, Boston, Massachusetts.
The authors report no conflicts of interest regarding the content herein.
Address for correspondence: Roger J. Laham, MD, BIDMC/Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215. Email: rlaham@bidmc.harvard.edu