Korean J Med.  2003 May;64(5):523-534.

A novel method of brachytherapy using local delivery of 99mTc-HMPAO for coronary stent restenosis

• Kim W
• Jeong MH
• Kim SH
• Park US
• Park OY
• Kim JH
• Bom HS
• Jeong HJ
• Ahn YK
• Cho JG
• Park JC
• Kang JC

Abstract

BACKGROUND: Restenosis after percutaneous coronary intervention (PCI) still remains a matter to be solved. We examined the inhibitory effects of local delivery of 99mTc-HMPAO (hexamethylprophylene amine oxime), a radioisotope, on neointimal hyperplasia after coronary stenting through an animal experiment, and observed its safety and efficacy for the patients with coronary stent restenosis.
METHODS
Stent overdilation injuries were performed in coronary arteries of 10 pigs. After stent overdilation injury, local radioisotope delivery using a 99mTc-HMPAO were performed in one coronary artery (Group I) and control therapy in another coronary artery in each pig (Group II). Follow-up coronary angiogram (CAG) and histopathologic assessment were performed at 4 weeks after stenting. Eleven patients (10 males, 62.4+/-5.7 years of age) underwent local administration of 30 mCi/ 2 mL of 99mTc-HMPAO shortly after PCI via Dispatch CatheterTM, and whole body bone scan and thallium-SPECT afterwards. Major adverse cardiac events (MACE) were assessed during one-year clinical follow-up.
RESULTS
On histopathologic analysis, neointimal area was 1.2+/-0.6 mm2 in Group I and 2.7+/-0.4 mm2 in Group II (p=0.002), and histopathologic area stenosis was 27.1+/-6.3% in Group I, 53.4+/-5.2% in Group II (p=0.001). In clinical study, eleven patients with coronary in-stent restenosis were enrolled. There was no in-hospital MACE. On quantitative coronary angiographic analysis minimal luminal diameter and diameter stenosis increased from 0.4+/-0.3 mm and 84.2+/-9.5% to 2.9+/-0.2 mm and 16.3+/-11.0% after PCI, respectively. Follow-up CAG was performed in 9 cases (81.8%) and restenosis occurred in 2 cases (22.2%). On follow-up CAG minimal luminal diameter was 2.0+/-0.8 mm, diameter stenosis rate 27.7+/-2.9 %, lumen loss 0.7+/-0.7 mm and loss index 0.2+/-0.3. During one-year clinical follow-up there were no cases of death and acute MI, but two cases of target vessel revascularization (18.2%).
CONCLUSION
Local delivery of 99mTc-HMPAO, one of the novel radiotherapies, can be used safely and effectively for coronary stent restenosis.

Keyword

Coronary artery diseases; Restenosis; Stents; Radioisotopes

MeSH Terms

Animal Experimentation
Brachytherapy*
Constriction, Pathologic
Coronary Artery Disease
Coronary Vessels
Follow-Up Studies
Humans
Hyperplasia
Male
Percutaneous Coronary Intervention
Phenobarbital
Radioisotopes
Radiotherapy
Stents*
Swine
Technetium Tc 99m Exametazime*
Phenobarbital
Radioisotopes
Technetium Tc 99m Exametazime