Incidence and predictors of late recurrence after β-radiation therapy with a 188Re-MAG3–filled balloon for diffuse in-stent restenosis
Received 28 May 2004; accepted 14 February 2005.
Background
The long-term fate of patent irradiated segments at 6 months after β-radiation therapy has not been sufficiently evaluated.
Methods
Two-year follow-up angiography was performed in 52 patients with patent irradiated segments at 6 months after β-radiation with a rhenium 188–mercaptoacetyltriglycine–filled balloon for diffuse in-stent restenosis. We evaluated late recurrence (LR) and its predictors after β-radiation.
Results
Late recurrence at 2 years after radiation was observed in 10 (19.2%) of 52 patients. The minimal lumen diameter (MLD) progressively decreased, from 2.67 ± 0.44 mm at postprocedure to 2.42 ± 0.53 mm at 6 months to 2.09 ± 0.75 mm at 2 years (P = .001). In the 42 patients without LR, the MLD decreased from postprocedure (2.74 ± 0.43 mm) to 6 months (2.44 ± 0.54 mm; P = .006), but did not change between 6 months and 2 years (2.35 ± 0.49 mm, P = .13). In the LR group, the MLD was unchanged from postprocedure (2.33 ± 0.29 mm) to 6 months (2.30 ± 0.43 mm; P = .81), but decreased significantly between 6 months and 2 years (1.02 ± 0.75 mm, P = .001). Multivariate analysis identified postprocedural MLD as an independent predictor of LR (odds ratio 0.025, 95% CI 0.007-0.94, P = .04). Late target lesion revascularization was performed in 6 patients (11.5%) between 6 months and 2 years after radiation.
Conclusion
Although LR after radiation was observed in some patients, irradiated segments remained stable for up to 2 years in most patients. Smaller postprocedural MLD, followed by delayed late loss between 6 months and 2 years, was associated with LR.
aDepartment of Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, South Korea
bDepartment of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
cDepartment of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
Reprint requests: Seong-Wook Park, MD, PhD, Department of Medicine, University of Ulsan College of Medicine, Asan Medical Center, 388-1 Poongnap-dong, Songpa-gu, Seoul, 138-736, South Korea.
This work was supported by grant no. 1999-2-206-001-3 from the Interdisciplinary Research Program of the KOSEF and the Cardiovascular Research Foundation, Seoul, South Korea.