From the Department of Medicine, Division of Cardiology, Cardiac Cath Lab and *Vascular Medicine and Intervention, Massachusetts General Hospital, Boston, Massachusetts. The authors report no conflicts of interest regarding the content herein. Manuscript submitted March 17, 2009, and accepted April 7, 2009. Address for correspondence: Creighton W. Don, MD, PhD, Massachusetts General Hospital, 55 Fruit St. GB800, Boston, MA 02114. E-mail: firstname.lastname@example.org
_______________________________________________ ABSTRACT: The use of the Rotablator rotational atherectomy device in the body of saphenous vein coronary grafts is currently contraindicated by the manufacturer (Boston Scientific Corp., Natick, Massachusetts). While rotational atherectomy in soft lesions in friable vein grafts would likely lead to complications, for severely calcified lesions that are non-dilatable, rotational atherectomy can arguably be performed safely. We present a case in which a non-dilatable, calcified saphenous vein coronary graft is successfully treated with rotational atherectomy.
J INVASIVE CARDIOL 2009;21:E168–E170 With the decline in the availability and use of directional coronary atherectomy and excimer laser devices, rotational atherectomy has become the primary interventional method used for plaque modification to facilitate the delivery of coronary stents in situations when balloon angioplasty is inadequate. The use of rotational atherectomy is currently contraindicated in saphenous vein grafts (SVGs) because atherosclerotic plaques in grafts tend to be soft and friable with associated thrombus formation.1,2 Additionally, older vein grafts may have an elevated risk for perforation. All clinical trials of rotational atherectomy evaluated its use in native coronaries.3 Previous reports of using rotational atherectomy in vein grafts describe cases of in-stent restenosis, anastamotic lesions or the native vessel disease treated via the graft.4–9 There has only been one prior report of using rotational atherectomy in a de novo stenosis in the body of a vein graft.6 We report a case in which rotational atherectomy was used successfully in the body of an old, calcified vein graft, with excellent procedural and clinical results. Case Report. A 73-year old male with a history of non-insulin-dependent diabetes, hypertension, peripheral vascular disease and a coronary artery bypass graft procedure presented with a non-ST-segment elevation myocardial infarction. He had few cardiac symptoms following his bypass surgery in 1987, in which he received a SVG to his left anterior descending artery (LAD) with a sequential graft to his first diagonal (D1), a vein graft to his first obtuse marginal, and a vein graft to his right posterior descending artery (PDA). He had claudication symptoms that improved after angioplasty of his right superficial femoral artery, and had been able to walk several miles, 4 times a week. He began experiencing moderate resting and exertional angina in the 2 months before presenting to the hospital with severe crushing substernal chest pain. His cardiac biomarkers were positive for myocardial injury and on electrocardiography (ECG), he had dynamic 2–3 mm ST depressions in leads V4–V6, I and aVL. He was started on eptifibatide and taken to the catheterization laboratory due to substantial ongoing chest pressure despite medical therapy. His left main and right coronary arteries were proximally occluded. The graft to the PDA was occluded, the graft to the circumflex was patent and the graft to the LAD-D1 had two 90% stenoses in the body of the graft, with the native LAD giving collateral vessels to the distal right coronary artery (Figure 1). An intra-aortic balloon pump was placed, but the patient continued to experience significant chest pressure and ST depressions. The case was urgently discussed with the cardiothoracic surgeons who felt that in light of the patient’s ongoing symptoms, unstable clinical presentation and bleeding risk from eptifibatide, the risk of reoperation was very high and they felt that an attempt at percutaneous intervention was warranted. Given that the ostial occlusions of the native vessels were old and long, a decision was made to open the culprit lesion in the vein graft to the LAD-D1, as this vessel supplied the anterior wall as well as the inferior wall via collaterals to the right coronary artery (RCA). Procedure. A 7 Fr sheath was placed in the right femoral artery using a modified Seldinger technique, through which a 7 Fr hockey-stick guiding catheter was introduced. A FilterWire (Boston Scientific Corp., Natick, Massachusetts) would not pass the proximal lesion, so a Floppy II coronary wire (Guidant Corp. Indianapolis, Indiana) was manipulated into the distal part of the distal LAD. Given the angulation, non-compliance and severe stenosis of the proximal lesion, no angioplasty balloons could be advanced. An Asahi Prowater coronary wire (Abbott Laboratories, Abbott Park, Illinois) was manipulated into the distal LAD as a “buddy wire”. A 2.0 x 15 mm compliant balloon was dilated to 12 atm and finally to 20 atm in the proximal and distal lesions, with significant “dog-boning” of the lesions and minimal improvement in angiographic appearance (Figure 2). A non-compliant 2.5 x 20 mm balloon was advanced with great difficulty and inflated to 20 atm in both lesions, again without yielding of the lesion. Attempts to advance a 3.0 x 15 mm Vision stent (Guidant Corp. Indianapolis, Indiana) were unsuccessful, again due to the anatomic features of the lesion. Several coronary guides were used (LBC, AL 2 and AL 3) to provide better backup support, but the stent could not be advanced into the proximal lesion. A Wiggle Wire (Abbott Laboratories) and a Cordis Stabilizer wire (Cordis Corp., Miami Lakes, Florida) were used, but the stent could not be advanced into the sharp proximal bend of the vein graft where the first calcified lesion was located. The patient was continuing to have chest pain and ECG changes with an intra-aortic balloon pump in place, so the decision was made to continue with the procedure. There was no angiographic appearance of thrombus or dissection. A 0.009 RotaWire (Boston Scientific) was advanced into the vein graft and the other wires removed. In order to reduce the angulation of the segment that the Rotablator burr would pass, the graft was deeply intubated with an AL3 guiding catheter so that its tip was at the origin of the proximal lesion (Figure 3). An intracoronary infusion of verapamil-nitroglycerin mixture through the RotaLink (Boston Scientific) central lumen was instituted. Two passes with a 1.5 mm burr were performed in the two lesions of the SVG at rotational speeds up to 170,000 rpm, without significant decelerations. The burr was removed from the vessel and a bolus of intracoronary nitroglycerin was administered. The angiographic appearance of the lesions showed reduced stenoses and stents were easily advanced into the vessel. A 3.5 x 18 Vision stent (Guidant Corp., Indianapolis, Indiana) was placed in the distal graft lesion and two 3.5 x 12 mm Vision stents were placed in the proximal stenosis, and both lesions were postdilated with a 3.5 x 18 non-compliant balloon to 14 atm. Thrombolysis in myocardial infarction (TIMI)-3 flow was maintained throughout the procedure and the final angiographic result was achieved with only a mild 10% residual defect in the proximal lesion (Figure 3). The patient was chest pain-free following the procedure and was discharged home without incident. At follow up he reported no anginal symptoms and a return to his baseline exercise capacity. He will be reassessed in 6–12 months. Discussion. Severely calcified and stenotic lesions can be highly resistant to balloon angioplasty, even when non-compliant balloons are deployed at high pressure. Lesion morphology of this type makes stent insertion difficult. Plaque modification and debulking techniques are effective in changing the size and compliance of the calcified lesions to improve deliverability of stents and balloons.10 These strategies are not frequently used in vein grafts since stenoses in the body of vein grafts are typically composed of soft atherosclerotic or thrombotic material that is friable and compliant.2 More often than not, embolization of this soft material is the primary complication of vein graft interventions. In the unusual circumstance that there is a non-dilatable, calcified lesion in the body of older grafts, cutting balloons, atherectomy catheters and laser ablation may be helpful in improving lesion compliance to facilitate stent delivery. Since balloon angioplasty has worse outcomes than angioplasty combined with stenting in coronary vein grafts, a debulking strategy that would allow for stent placement is preferable if angioplasty alone is insufficient to allow for stent delivery.11,12 The multicenter randomized trial of angioplasty versus directional coronary atherectomy (CAVEAT II) showed that directional coronary atherectomy achieved better immediate angiographic success in vein grafts with similar outcomes at 6 months, although with more intraprocedural complications.13 The excimer laser can also be employed effectively in vein grafts. The Percutaneous Excimer Laser Coronary Angioplasty Registry reported a 92% procedural success in treating vein graft lesions, particularly ostial lesions.14 There were, however, 48 patients who had dissections, 7 with minor perforations, but no major perforations. Other extraction or atherectomy devices have been associated with high rates of embolization and other complications.15,16 With these less-than-favorable studies, debulking devices are rarely used in SVGs in the coronary stent era. This case illustrates that there is still a role for debulking devices in highly calcified, non-dilatable lesions on vein grafts. Directional coronary atherectomy catheters or excimer lasers could not be used for the present patient since the stenosis, tortuosity and angulation of the proximal graft lesion would not have allowed passage of these bulky devices. Rotational atherectomy was performed safely without complications. Thomas et al reported the safe and effective use of rotational atherectomy to facilitate angioplasty in 14 patients with vein graft stenoses. These were primarily lesions at anastomotic sites. The authors used the atherectomy device in 1 case of in-stent restenosis within the body of a graft.4,5 The manufacturer currently states that the use of the Rotablator is contraindicated in vein grafts based on the concern for embolization of soft atherosclerotic tissue and perforation of friable vein grafts.1 While we share these concerns and do not recommend its use in routine vein graft cases, we feel that rotational atherectomy is a feasible option for non-dilatable, calcified lesions in mature grafts as long as there is no evidence of thrombus or vessel dissection.
2. Neitzel GF, Barboriak JJ, Pintar K, Qureshi I. Atherosclerosis in aortocoronary bypass grafts. Morphologic study and risk factor analysis 6 to 12 years after surgery. Arteriosclerosis 1986;6:594‚Äì600.
3. Silber S, Albertsson P, Aviles FF, et al. Guidelines for percutaneous coronary interventions. The Task Force for Percutaneous Coronary Interventions of the European Society of Cardiology. Eur Heart J 2005;26:804‚Äì847.
4. Thomas WJ, Cowley MJ, Vetrovec GW, et al. Effectiveness of rotational atherectomy in narrowed left internal mammary artery grafts to the left anterior descending coronary artery. Am J Cardiol 2000;86:86‚Äì88.
5. Thomas WJ, Cowley MJ, Vetrovec GW, et al. Effectiveness of rotational atherectomy in aortocoronary saphenous vein grafts. Am J Cardiol 2000;86:88‚Äì91.
6. Coto H. Intravascular ultrasound-guided rotational atherectomy and stent implant in a previously undilatable saphenous vein graft lesion. J Invasive Cardiol 1998;10:451‚Äì453.
7. Baron SB, Arthur A. Rotational atherectomy for resistant anastomotic saphenous vein bypass graft stenosis. J Invasive Cardiol 1996;8:120‚Äì122.
8. Cardenas JR, Strumpf RK, Heuser RR. Rotational atherectomy in restenotic lesions at the distal saphenous vein graft anastomosis. Cathet Cardiovasc Diagn 1995;36:53‚Äì57; discussion 58.
9. Abhyankar AD, Vaidya KA, Bernstein L. Rotational atherectomy of calcified ostial saphenous vein graft lesion with long term follow-up: A case report. Int J Cardiol 1995;52:11‚Äì12.
10. Bittl JA. Role of adjunct devices: Cutting balloon, thrombectomy, laser, ultrasound, and atherectomy. In: Topol EJ (ed.). Textbook of Interventional Cardiology. Philadelphia: Saunders, Elsevier. 2008, p. 635.
11. Keeley EC, Velez CA, O‚ÄôNeill WW, Safian RD. Long-term clinical outcome and predictors of major adverse cardiac events after percutaneous interventions on saphenous vein grafts. J Am Coll Cardiol 2001;38:659‚Äì665.
12. Savage MP, Douglas JS Jr, Fischman DL, et al. Stent placement compared with balloon angioplasty for obstructed coronary bypass grafts. Saphenous Vein De Novo Trial Investigators. N Engl J Med 1997;337:740‚Äì747.
13. Holmes DR Jr, Topol EJ, Califf RM, et al. A multicenter, randomized trial of coronary angioplasty versus directional atherectomy for patients with saphenous vein bypass graft lesions. CAVEAT-II Investigators. Circulation 1995;91:1966‚Äì1974.
14. Bittl JA, Sanborn TA, Yardley DE, et al. Predictors of outcome of percutaneous excimer laser coronary angioplasty of saphenous vein bypass graft lesions. The Percutaneous Excimer Laser Coronary Angioplasty Registry. Am J Cardiol 1994;74:144‚Äì148.
15. Moses JW, Moussa I, Popma JJ, et al. Risk of distal embolization and infarction with transluminal extraction atherectomy in saphenous vein grafts and native coronary arteries. NACI Investigators. New approaches to coronary interventions. Catheter Cardiovasc Interv 1999;47:149‚Äì154.
16. Dooris M, Hoffmann M, Glazier S, et al. Comparative results of transluminal extraction coronary atherectomy in saphenous vein graft lesions with and without thrombus. J Am Coll Cardiol 1995;25:1700‚Äì1705.