Correspondence
Brachytherapy and Saphenous-Vein Grafts
N Engl J Med 2002; 347:692-693August 29, 2002
- Article
To the Editor:
Radiation treatment undoubtedly reduces the risk of recurrence of in-stent restenosis. However, the findings of Waksman et al. (April 18 issue)1 should be taken in the context of two facts. First, although the greatest need for target-lesion revascularization (that is, restenosis) occurs within the first 8 months after the procedure, the risk of restenosis after vein-graft intervention continues to rise until 18 to 24 months after the procedure, suggesting a phenomenon of late restenosis that is unique to vein-graft intervention.2,3 Therefore, longer follow-up (perhaps with follow-up angiography at 24 months) would be helpful in judging the magnitude of the beneficial effect of radiation. Second, clinical recognition of restenosis after vein-graft intervention is often difficult because of coexisting multivessel disease and the presence of collaterals, which limit the interpretation of myocardial-perfusion studies and symptoms.4 Although this effect was equal in the two groups (since the study was randomized and blinded), it would be helpful to know whether target-lesion revascularization was driven by ischemia or by symptoms.
4 ReferencesSanjiv Sharma, M.D.
William Nyitray, M.D.
Brijesh Bhambi, M.D.
Bakersfield Heart Hospital, Bakersfield, CA 93301
sanjiv1122@yahoo.com 1
Waksman R ,Ajani AE ,White RL , et al. Intravascular gamma radiation for in-stent restenosis in saphenous-vein bypass grafts. N Engl J Med 2002;346:1194-1199
Full Text | Web of Science | Medline2
Hong MK ,Mehran R ,Dangas G , et al. Comparison of time course of target lesion revascularization following successful saphenous vein graft angioplasty versus successful native coronary angioplasty. Am J Cardiol 2000;85:256-258
CrossRef | Web of Science | Medline3
Le May MR ,Labinaz M ,Marquis J , et al. Predictors of long-term outcome after stent implantation in a saphenous vein graft. Am J Cardiol 1999;83:681-686
CrossRef | Web of Science | Medline4
Safian RD, Freed MS, eds. The manual of interventional cardiology. 3rd ed. Royal Oak, Mich.: Physicians Press, 2001:324.
Author/Editor Response
The authors reply:
To the Editor: In published trials of intracoronary radiation therapy for in-stent restenosis, the majority of target-lesion revascularizations were performed within the first six to nine months after the initial procedure. Angiographic analysis at this time allows assessment of the efficacy of treatment, in addition to that provided by clinical follow-up.1-3 Although late restenosis in patients who receive radiation can occur after this period, judicious clinical follow-up will identify the majority of patients with restenosis who require repeated intervention. Assessment of vein-graft failure is challenging because many of these grafts have diffuse disease and because totally occluded grafts do not necessarily represent the status of the target lesion, since other blockages could have contributed to the occlusion. Therefore, it is encouraging that the data in our article continue to hold for target-vessel revascularization.
In all the cases in our series, the decision to perform target-lesion revascularization was driven either by symptoms refractory to medical therapy or by evidence of ischemia on functional testing (exercise testing or myocardial-perfusion studies). We agree that clinical recognition of restenosis after vein-graft intervention may be challenging because of the presence of multivessel disease and collaterals; however, these confounders should have occurred equally in the two treatment groups, since the study was randomized and blinded. Revascularization was performed only when angiographic restenosis correlated with the clinical assessment — an approach that we believe reflects “real-world” clinical management.
3 ReferencesRon Waksman, M.D.
Andrew E. Ajani, M.D.
Washington Hospital Center, Washington, DC 20010
ron.waksman@medstar. net 1
Waksman R ,White RL ,Chan RC , et al. Intracoronary gamma-radiation therapy after angioplasty inhibits recurrence in patients with in-stent restenosis. Circulation 2000;101:2165-2171
Web of Science | Medline2
Teirstein PS ,Massullo V ,Jani S , et al. Catheter-based radiotherapy to inhibit restenosis after coronary stenting. N Engl J Med 1997;336:1697-1703
Full Text | Web of Science | Medline3
Leon MB ,Teirstein PS ,Moses JW , et al. Localized intracoronary gamma-radiation therapy to inhibit the recurrence of restenosis after stenting. N Engl J Med 2001;344:250-256
Full Text | Web of Science | Medline
