Suitability of Saphenous Vein Graft Lesions for the Use of Distal Embolic Protection Devices

ABSTRACT: The use of distal embolic protection devices (EPD) in saphenous vein graft percutaneous interventions (SVG-PCI) has been associated with a decrease in adverse events. Currently, there are limited data regarding the percentage of SVG lesions that are suitable for EPD deployment. We retrospectively reviewed 131 SVG-PCI procedures occurring over 18 months for suitability for EPD deployment, utilizing previously published suitability criteria. We found that 49% of cases were suitable for EPD use, which is similar to results from other studies. Given the data supporting the use of EPD use in SVG-PCI, we feel that these findings should motivate interventional operators to establish benchmark standards for employing EPDs to improve the care of patients undergoing SVG-PCI. J INVASIVE CARDIOL 2008;20:568–570 The use of distal embolic protection devices (EPDs) has been shown to reduce the incidence of major cardiac events in patients undergoing saphenous vein graft percutaneous intervention (SVG-PCI).1,2 Utilizing a large multicenter cohort of patients, we recently reported that only 22% of patients undergoing SVG-PCI in the American College of Cardiology National Cardiovascular Data Registry were treated with EPDs.3 However, there are limited data regarding the suitability of SVG lesions for EPD deployment. Current knowledge of the percentage of vein graft lesions suitable for EPDs appears to be derived from two retrospective angiographic reviews, which estimate that 43–57% of SVG lesions are technically eligible for this approach.4,5 We therefore evaluated unselected patients undergoing SVG-PCI at our institution for EPD suitability, utilization, and deployment success rates. Methods We performed a descriptive, cross-sectional study by analyzing consecutive patients in a registry at the Mid-America Heart Institute who underwent SVG-PCI between June 2004 and December 2005. Two cardiologists independently reviewed angiographic images to determine lesion suitability for EPD deployment. The suitability criteria for EPD use were derived from prior studies of single-center experiences4,5 and included vessel diameter 3.5–5.5 mm, lesion > 5 mm from the aortic anastomosis, distal landing zone ≥ 25 mm from the native vessel anastomosis (determined visually), and lack of tortuosity in the device landing zone. Grafts with severe degeneration or ectasia that lacked an adequate landing zone were deemed not suitable for EPD deployment, as was the inability to protect a limb of a sequential graft. Differences between the observers were planned for adjudication by an experienced third interventional cardiologist. Baseline characteristics are presented as medians (interquartile ranges) or means ± standard deviations for continuous variables and percentages for categorical variables. Results During the study period, a total of 131 SVG-PCIs were performed on 131 SVG lesions. The baseline characteristics of our patient population are shown in Table 1 and are relatively comparable to the population studied by Mathew et al.4 In both studies, vein graft age was approximately 11–12 years. No lesions in our study required adjudication by the third interventional cardiologist, and 50 of the 131 (38%) underwent placement of an EPD. No device failures occurred in these patients. Of the 131 stenoses evaluated, 64 (49%) were considered suitable for EPD deployment. Comparison of these results against prior studies is shown in Table 2, including mortality among patients with anatomy suitable and unsuitable for EPD utilization. Figures 1–2 demonstrate an example of a significant SVG stenosis, with suitability criteria identified. Discussion In our retrospective analysis, we determined that nearly half of SVG stenoses were suitable for EPD deployment. Findings are similar in two previously published angiographic reviews demonstrating suitability for distal protection between 36% and 57% of consecutive patients undergoing SVG-PCI.4,5 No data are available regarding operator rationale for selecting or not selecting EPDs, but one study involving both drug-eluting and bare-metal stents demonstrated that only 19–20% of patients undergoing SVG-PCI received an EPD6 despite Class I recommendations from national guidelines for utilization of these devices when technically feasible.7 Our registry confirmed these findings in contemporary practice, as 15 of 64 individuals (23%) with suitable anatomy did not undergo deployment of an EPD, which mirrors utilization rates nationally.3 Conclusions Given the high adverse complication rates associated with SVG-PCI and the significant reduction in adverse events seen in randomized studies employing EPDs during these interventions,1,2 we feel that efforts should be made by the interventional cardiology community to increase utilization of these devices for appropriate lesions. We also believe that our current findings, when viewed in aggregate with other reports, should motivate interventional operators to establish benchmark standards for employing EPDs to improve the care of patients undergoing SVG-PCI.

1. Baim DS, Wahr D, George B, et al. Randomized trial of a distal embolic protection device during percutaneous intervention of saphenous vein aorto-coronary bypass grafts. Circulation 2002;105:1285–1290.
2. Stone GW, Rogers C, Hermiller J, et al. Randomized comparison of distal protection with a filter-based catheter and a balloon occlusion and aspiration system during percutaneous intervention of diseased saphenous vein aorto-coronary bypass grafts. Circulation 2003;108:548–553.
3. Mehta SK, Frutkin AD, Milford-Beland S, et al. Utilization of distal embolic protection in saphenous vein graft interventions (an analysis of 19,546 patients in the American College of Cardiology-National Cardiovascular Data Registry). Am J Cardiol 2007;100:1114–1118.
4. Mathew V, Lennon RJ, Rihal CS, et al. Applicability of distal protection for aortocoronary vein graft interventions in clinical practice. Catheter Cardiovasc Interv 2004;63:148–151.
5. Webb LA, Dixon SR, Safian RD, O'Neill WW. Usefulness of embolic protection devices during saphenous vein graft intervention in a nonselected population. J Interv Cardiol 2005;18:73–75.
6. Ge L, Iakovou I, Sangiorgi GM, et al. Treatment of saphenous vein graft lesions with drug-eluting stents: Immediate and midterm outcome. J Am Coll Cardiol 2005;45:989–994.
7. Smith SC Jr, Feldman TE, Hirshfeld JW Jr, et al. ACC/AHA/SCAI 2005 guideline update for percutaneous coronary intervention: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (ACC/AHA/SCAI Writing Committee to Update 2001 Guidelines for Percutaneous Coronary Intervention). Circulation 2006;113:e166–e286.