The Parallel Wire Technique to Deal with Wire-Induced Dissection of a Complex Calcified Lesion

Case Report. A 75-year-old male presented to our catheterization laboratory with exertional shortness of breath (Canadian Cardiovascular Society Class 2–3) and a positive dipyridamole nuclear scan with ischemia in the infero-lateral territory which was performed for risk stratification prior to upcoming vascular surgery. His past history was significant for hypertension, hyperlipidemia and smoking. Cardiac catheterization was performed.
The left main artery and the left anterior descending artery had mild disease only. The first obtuse marginal was occluded at its ostium. The right coronary artery (RCA) had a proximal 50% lesion followed by a critical 95% calcified proximal-to-mid segment lesion followed by mild distal disease (Figure 1). This appeared to be the revascularizable culprit lesion.
The right coronary artery (RCA) was therefore engaged with a JR4 Viking^® (Guidant Corp., Indianapolis, Indiana) guiding catheter. Initially, a Pilot 50™ (Guidant) wire and a Whisper MS^® (Guidant ) wire were tried, and both were unable to cross the lesion. We therefore tried a second Pilot 50 wire with a slight secondary bend, which after a prolonged attempt, managed to cross the lesion, however the tip was not free and the progression of the wire was not smooth. At this point, we could not be sure of wire placement since even in orthogonal views the wire appeared to be intraluminal, however it was not progressing forward easily. We therefore chose to withdraw this wire. The next cineangiogram (CINE) demonstrated a complex NHLBI type C dissection with extraluminal contrast staining but preserved flow (Figure 2). At this point, multiple attempts were made with a Pilot 50 wire, a Whisper MS wire and a Wizdom Supersoft™ (Cordis Corp., Miami, Florida) wire to find the true lumen, however all attempts passed the wire into the false lumen each time in spite of multiple interrogations at all angles at the lesion site. At this point, we left a Pilot 50 wire in the false lumen to see if we could “seal” the entry point into the false channel. Next, a Wizdom wire was advanced without much difficulty distally past the previously difficult-to-cross segment (Figure 3). This wire was passed into a side branch (an acute marginal distal to the lesion) on purpose to further prove entry into the true lumen (Figure 3). When this was confirmed with a CINE, we passed this wire into the distal RCA with ease. At this point, the Pilot 50 wire was removed from the false lumen. The flow in the vessel was compromised to TIMI grade 2, likely demonstrating extension of the dissection to a type F dissection at this point. A Mercury^® (Abbott Laboratories, Abbott Park, Illinois) 2.0 x 11 mm balloon was inflated at 8 atm along the length of the lesion and this again restored TIMI 3 flow, but demonstrated a long area of dissection.
Due to the tortuous nature and severe calcification in the vessel, we chose to deliver several short stents to cover the long dissection. Therefore, two 3.0 x 15 mm Lekton Motion™ (Biotronik, Inc., Lake Oswego, Oregon) stents were placed in an overlapping fashion followed by a third 3.0 x 18 mm Lekton Motion stent to completely cover the lesion and the entire dissection. TIMI grade 3 flow with an optimal angiographic result was obtained (Figure 4). There was no rise in troponin or CK-MB postprocedure. The patient was doing well at clinical follow up 1 month later.

Discussion. Intravascular ultrasound and angioscopy studies have reported the incidence of coronary dissections to be as high as 60–80% prior to the availability of stents.^4,5 The National Heart, Lung and Blood Institute (NHLBI) has classified coronary dissections according to severity from A through F. These are defined as: (A) minimal radiolucency, not persistent (luminal haziness); (B) “double lumen”, not persistent (linear dissection); (C) extraluminal cap with persistence of contrast dye after the lumen has cleared (extra-luminal contrast staining); (D) spiral dissection; (E) persistent new filling defect (dissection with reduced flow or may represent thrombus); (F) dissection resulting in impaired flow/total occlusion.³
Predictors of coronary dissection can include a balloon-to-artery ratio >1.1, calcification, presence of other lesions in the target vessel and lesion length.⁶ Generally, type A and B dissections are usually benign and generally have a favorable outcome, with acute closure rates of approximately 3%.7 Complex dissections, on the other hand, have significant morbidity and mortality associated with a five- to ten-fold increase in the rate of death/myocardial infarction or emergent bypass surgery.^7,8 The parallel wire technique has been described before in two settings. First, as a chronic total occlusion crossing technique, and second, to recanalize catheter-induced spiral dissections of the RCA.^1,2
Our use of the parallel wire technique for wire-induced dissections of the coronary artery is on a slightly different basis. Often after a wire dissection, repeated entry into the false lumen is very common since this is often the path of least resistance for the wire once a false channel has been established. With our method, the first wire is engaged into the false channel to hopefully “seal off” the entry point to this false lumen to prevent entry of the second or third wires repeatedly into this channel and to allow for wiring of the true lumen, as was the case with our patient. More than one wire may be required to seal off the entry point to the false lumen. Of note is that our second wire did in fact cross over the first wire and also penetrated the lesion from the outer curvature of the vessel, satisfying two of the criteria of the successful parallel wire technique as described by Ochiai and others (for the chronic total occlusion parallel wire technique).¹
We therefore describe a novel use for the parallel wire technique for wire-induced dissections to recanalize complex wire-induced dissections successfully. Since this is a reasonably challenging and not always successful technique, the option of coronary artery bypass surgery should always be given consideration with extensive coronary dissection. Limitations and issues with this technique can include extension of the dissection plane and perforation with repeated attempts at wiring the true lumen and risk of subsequent infarction and its consequences. Operator experience and patience in careful wiring are essential to the success of this higher-risk technique. Complex coronary dissections carry significant morbidity and mortality risk for patients, and the use of novel techniques may help to alleviate some of this risk.

References

1. Ochiai M, Ashida K, Araki H, et al. The latest wire technique for chronic total occlusion. Ital Heart J 2005;6:489–493.
2. Chai HT, Yang CH, Wu CJ, et al. Utilization of a double wire technique to treat long extended spiral dissection of the right coronary artery: Evaluation of incidence and mechanisms. Int Heart J 2005;46:35–44.
3. Halabi AR, Sketch MH Jr, Tcheng JE, et al. Which is the true channel? J Invasive Cardiol 2004;16:716–718.
4. Kovach JA, Mintz GS, Pichard AD, et al. Sequential intravascular ultrasound characterization of the mechanisms of rotational atherectomy and adjunct balloon angioplasty. J Am Coll Cardiol 1993;22:1024–1032.
5. den Heijer P, Foley DP, Escaned J, et al. Angioscopic versus angiographic detection of intimal dissection and intracoronary thrombus. J Am Coll Cardiol 1994;24:649–654.
6. Sharma SK, Israel DH, Kamean JL, et al. Clinical, angiographic, and procedural determinants of major and minor coronary dissection during angioplasty. Am Heart J 1993;126:39–47.
7. Ferguson JJ, Barasch E, Wilson JM, et al. The relation of clinical outcome to dissection and thrombus formation during coronary angioplasty. Heparin Registry Investigators. J Invasive Cardiol 1995;7:2–10.
8. Huber MS, Mooney JF, Madison J, Mooney MR. Use of a morphologic classification to predict clinical outcome after dissection from coronary angioplasty. Am J Cardiol 1991;68:467–471.