Extra-stent vascular remodeling in in-stent restenosis after 188Re-MAG3 radiation therapy.
BACKGROUND
The effect of beta-radiation on extra-stent vascular remodeling in patients with in-stent restenosis has not been studied. The correlation between the extent of extra-stent plaque proliferation and that of intimal hyperplasia (IH) in in-stent restenosis in patients who received beta-radiation therapy as well as conventional therapy has also not been studied.


METHODS
We evaluated the extra-stent remodeling in diffuse in-stent restenosis between a beta-radiation therapy patient group (188Re-MAG3, n=50) and a control group (n=9) by applying serial intravascular ultrasound (IVUS) analysis. Matching (post-intervention and follow-up) images were acquired at the follow-up lesion site and were available in 44 of 50 patients who received radiation therapy and in seven of nine control patients.


RESULTS
There was a significant increase of the external elastic membrane (EEM) area in both groups: 16.4 +/- 3.3 mm2 post-intervention to 17.1 +/- 3.3 mm2 at follow-up, P=0.001 in the radiation therapy group, and 16.8 +/- 4.0 mm2 post-intervention to 17.4 +/- 4.1 mm2 at follow-up, P=0.008 in the control group. There were no statistically significant differences of the Delta EEM area between the two groups: 0.7 +/- 0.4 mm2 in the radiation therapy group vs. 0.6 +/- 0.4 mm2 in the control group, P=0.389. The Delta IH area correlated with the Delta EEM area in the control group (r=0.826, P=0.022), but not in the radiation therapy group (r=0.016, P=0.919).


CONCLUSIONS
The findings of this IVUS study were that positive remodeling (increased EEM area) occurred equally in both control and irradiated patients with in-stent restenosis. The extent of remodeling was directly in proportion to IH in the control group, but no such relationship existed in the irradiated patient group.
Hong
Myeong-Ki
MK
Department of Medicine, University of Ulsan College of Medicine, Cardiac Center, Asan Medical Center, 388-1 Poongnap-dong, Songpa-gu, 138-736, Seoul, South Korea
Park
Seong-Wook
SW
Moon
Dae-Hyuk
DH
Oh
Seung-Jun
SJ
Lee
Cheol-Whan
CW
Kim
Young-Hak
YH
Kim
Jun-Hong
JH
Zhang
Yuanchun
Y
Song
Jong-Min
JM
Kang
Duk-Hyun
DH
Song
Jae-Kwan
JK
Kim
Jae-Joong
JJ
Park
Seung-Jung
SJ
D016022:Case-Control Studies; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000532:radiotherapy*; D005500:Follow-Up Studies; D006801:Humans; D006965:Hyperplasia; D009842:Oligopeptides / Q000627:therapeutic use; D009942:Organometallic Compounds / Q000627:therapeutic use; D011868:Radioisotopes / Q000627:therapeutic use*; D019275:Radiopharmaceuticals / Q000627:therapeutic use*; D015203:Reproducibility of Results; D012211:Rhenium / Q000627:therapeutic use*; D015607:Stents; D013997:Time Factors; D017539:Tunica Intima / Q000473:pathology; D018084:Ultrasonography, Interventional
D009842:Oligopeptides; D009942:Organometallic Compounds; D011868:Radioisotopes; D019275:Radiopharmaceuticals; C114893:rhenium-mercaptoacetyltriglycine; D012211:Rhenium