Late vascular response to repeat stenting for in-stent restenosis with and without radiation: an intravascular ultrasound volumetric analysis.
BACKGROUND
Re-stenting of in-stent restenosis (ISR) improves acute angiographic results. Methods and Results- Volumetric intravascular ultrasound analysis was performed in 70 ISR lesions that received either placebo (n=36) or (192)Ir radiation (n=34). ISR lesions treated by re-stenting were divided into 3 groups: old stent not re-stented (A), old/new stent overlap (B), and new stent only (C). ISR lesions treated without re-stenting were categorized as D. In placebo patients, postintervention lumen volume index (LVI) was significantly greater in re-stented segments B and C than in non-re-stented segment A (P<0.05).At follow-up, however, LVI was similar in all 4 segments secondary to the increased intimal hyperplasia (IH) reaccumulation within the re-stented segments. In patients treated with (192)Ir radiation, LVI was maintained from baseline to follow-up only in non-re-stented segments A and D. Conversely, there was a significant decrease in LVI in re-stented segments B and C (P<0.05). Qualitatively, 79% of patients in the irradiated group had stent struts with undetectable neointimal versus only 27% in the placebo group (P<0.001). Coefficient of variation of IH reaccumulation was greater in re-stented segments of (192)Ir patients (B=57.3% and C=58.9%) than in re-stented segments in placebo patients (B=27.3% and C 26.8%) and non-re-stented segments in irradiated patients.


CONCLUSIONS
Additional lumen gain from re-stenting ISR lesions is counteracted by exaggerated neointimal proliferation in placebo patients. Maximum effectiveness and safety of radiation can be achieved for ISR lesions when treated without re-stenting. Thus, regardless of supplementary intravascular brachytherapy, repeat stenting strategies provided little long-term advantage.
Morino
Yoshihiro
Y
Center for Research in Cardiovascular Interventions, Stanford University Medical Center, Stanford, CA, USA.
Limpijankit
Thosaphol
T
Honda
Yasuhiro
Y
Lansky
Alexandra J
AJ
Waksman
Ron
R
Bonneau
Heidi N
HN
Yock
Paul G
PG
Mintz
Gary S
GS
Fitzgerald
Peter J
PJ
D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects; D001918:Brachytherapy; D015331:Cohort Studies; D023903:Coronary Restenosis / Q000000981:diagnostic imaging* / Q000517:prevention & control / Q000601:surgery*; D018450:Disease Progression; D004311:Double-Blind Method; D005500:Follow-Up Studies; D005720:Gamma Rays / Q000627:therapeutic use; D006801:Humans; D007496:Iridium Radioisotopes / Q000627:therapeutic use; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012008:Recurrence; D012086:Reoperation; D015607:Stents / Q000009:adverse effects*; D013988:Ticlopidine / Q000627:therapeutic use; D013995:Time; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional; D014654:Vascular Patency / Q000528:radiation effects
D007496:Iridium Radioisotopes; D010975:Platelet Aggregation Inhibitors; D013988:Ticlopidine