Highlights
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The development of many chronic total obstruction (CTO) techniques together with the hardware advancements have led to the improvement of the success rate of CTO percutaneous coronary interventions (PCI). The key point for a successful PCI regarding a CTO is the crossing of the wire through the occlusion, and this can be achieved by antegrade or retrograde techniques.
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However in some cases and after the crossing of the guidewire, specific difficulties may appear, requiring changes of the initial plan.
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We describe for the first time the “Proximal anchoring distal trapping” technique. We used this technique in a case of CTO PCI of the right coronary artery (RCA) that after antegrade advancement of the guidewire, the lesion was unable to cross.
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This technique is a combined technique, easy to use as it requires 6 Fr catheters and it can be the last resource before switching to the retrograde approach
The development of many chronic total obstruction (CTO) techniques together with the hardware advancements have led to the improvement of the success rate of CTO percutaneous coronary interventions (PCI) [ , ]. The key point for a successful PCI regarding a CTO is the crossing of the wire through the occlusion, and this can be achieved by antegrade or retrograde techniques. However in some cases even after the crossing of the guidewire, specific difficulties may appear, requiring changes of the initial plan. Balloon uncrossable CTOs are defined as lesions that cannot be crossed with a balloon after successful guidewire crossing. They are the second most common reported reason for CTO PCI failure, encountered in 5–10% of cases, they are associated with high rates of technical failure and they require specialized techniques for successful treatment [ , ].
Although several techniques can be used to help to cross such lesions, the majority of them require 7 or 8 Fr guiding catheters and many materials or devices that they should be available at the time of the intervention. Such techniques include balloon-assisted microdissection (also called grenadoplasty) [ ], anchoring techniques [ ], guide catheter extensions [ ], the Threader catheter (combined balloon/microcatheter, Boston Scientific, Natick, Massachusetts) [ ], the Tornus catheter (Asahi Intecc, Nagoya, Japan) [ ], rotational atherectomy [ ] and some other more rarely used techniques [ ]. Moreover subintimal techniques that include subintimal space plaque modification, or subintimal distal anchoring technique can be used in these difficult to cross lesions [ ] ( Table 1 ).
| Technique | Short description | Ref |
|---|---|---|
| Balloon-assisted micro dissection | Advancement of a balloon as far as possible into the proximal cap and inflated until it ruptures, causing microdissections around and into the cap | [ ] |
| Extension catheters | Creates a smooth pathway for balloon and/or stent delivery by providing greater flexibility and a smooth surface | [ ] |
| Ping pong technique | Use of two guiding catheters into the same coronary artery | [ ] |
| Anchoring techniques | Inflation of a balloon in the side branch of a target coronary vessel to facilitate equipment delivery to a target lesion. (coaxial and distal anchoring) | [ ] |
| Laser | Application of laser in the coronary wall that causes photomechanical and photochemical interactions resulting in the debulking of the coronary plaque | [ , ] |
| Tornus | Enlarges the channel of the blood vessel, enabling easy access of other PCI devices, making treatment of tight lesions possible. | [ ] |
| Rotational atherectomy | Debulking of calcified coronary plaques | [ ] |
| Threader | Microdilatation catheter | [ ] |
| Subintimal techniques | Subintimal space plaque modification, or subintimal distal anchoring | [ ] |
We describe a case of CTO PCI of the right coronary artery (RCA) that after antegrade advancement of the guidewire, the lesion was unable to cross. We describe for the first time the “proximal anchoring distal trapping technique” that was used for the crossing of this lesion.
A 65 yrs. male with a history of PCI in the RCA ten years ago, was admitted to our hospital due to angina pectoris (Canadian Cardiovascular Society grading II) that was exacerbated during the last 6 months. He was also suffering from diabetes mellitus under metformin treatment and hypertension. The patient had a diagnostic coronary catheterization three years earlier that showed that proximal occlusion of the RCA with no other significant stenoses. During the current admission the electrocardiogram was normal and the cardiac ultrasound showed hypokinesia of the inferior-posterior wall with LVEF of 55%. Biochemical profile and the troponin levels were normal. The coronary angiography showed left main (LM), left anterior descending coronary artery (LAD) and left circumflex artery (LCX) with no significant stenosis while the RCA was occluded at the proximal part with a J CTO Score of 3. Retrograde filling of the distal RCA via collaterals from the LAD was observed with a Rentrop classification of 2 and an estimated Werner classification of the collaterals of CC2 ( Fig. 1 A ).
