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Totally occluded saphenous vein graft recanalization: A dangerous option

Percutaneous treatment for saphenous vein graft disease continues to be a challenging procedure. High periprocedural morbidity related with distal embolization of atherothrombotic debris [1] and its sequela of myocardial infarction and death, high restenosis rate, even after stent placement [2,3], and high rate of progression of untreated angiographically nonsignificant lesions [4] are the problems to be solved. These difficulties are explained by the pathologic differences with native vessels atherosclerotic disease. Vein graft atherosclerosis tends to be diffuse, soft, and friable with poorly developed or absent fibrous cap. Histologically the vein graft atheroma has more foam and inflammatory cells, necrotic debris, cholesterol crystals and blood elements [5–7]. Thrombus of varying ages is a frequent component of the obstructive material. When graft thrombosis and occlusion occurs the absence of branches favor large and bulky thrombus formation that occupy the entire length of the vein [8,9]. Interventions maneuvers (guiding catheter ostium canalization, coronary wire vein crossing, lesion balloon dilatation, stent implantation, and balloon stent expansion can dislodge friable atherosclerotic and thrombotic material causing distal embolization and slow-flow or no-reflow phenomena. Vasoactive substances can contribute to no-reflow. Creatine kinase-MB (CK-MB) elevation is a frequent consequence after distal embolization [1,10] and it is related with one-year mortality rate despite angiographic results [11]. Selective infusion of urokinase [12], extraction coronary atherectomy [13], directional coronary atherectomy [14], laser angioplasty [15], ultrasound thrombolysis [16], and AngioJet rapid thrombectomy [17] has been used in an effort to reduce distal embolization. These techniques have generally failed in reducing the incidence of complications related with saphenous vein PCI. A novel device under investigation that can be mentioned is the X-sizer, a tromboatherectomy system [18]. Other maneuvers utilized in order to reduce distal embolization are direct stenting and covered stents implantation to isolate the friable atherosclerotic material [19]. The PercuSurge GuardWire system distal protection device combines an elastomeric balloon to occlude distally the conduit with a monorail aspiration catheter to retrieve the debris. The SAFER randomized trial demonstrate a highly significant reduction in major adverse events using this distal protection device compared with stenting over a conventional angioplasty guidewire [20]. Other distal protection devices based on porous filters are under investigation to establish their efficacy in distal embolization prevention [21]. The highest-risk group in the cohort of patients with degenerated saphenous vein graft disease that could be treated by percutaneous intervention are those with occluded vein grafts [22–24]. Large, bulky thrombus that occupies completely the residual vein lumen can be easily dislodged and a large amount of embolic material can be released during the procedure. In these high-risk patients short and longer-term outcome remains poor and the incidence of reocclusion and the need of repeat revascularization is high [23,24]. Potential benefits of totally occluded saphenous vein graft recanalization must be considered on an individual basis and related with the risk of the procedure. It is extremely important to take into account that the attempt can transform a stable condition in a worse situation as a consequence of distal embolization and Q or non-Q wave acute myocardial infarction. In this issue, Rajdeep et al. proposed the association of an occlusive balloon-based distal protection device (PercuSurge GuardWire system, Medtronic AVE, Minneapolis, MN) with a rheolytic thrombectomy device (AngioJet, Possis Medical, Minneapolis, MN) to treat totally occluded saphenous vein grafts. The magnitude of thrombus debris present in totally occluded vein graft made difficult its removal with the monorail aspiration catheter of the PercuSurge GuardWire system. The association of a more efficient system of thrombus retrieval (AngioJet rheolytic thrombectomy system) under the em-