Five-year clinical and angiographic follow-up after intracoronary iridium-192 radiation therapy.
BACKGROUND
Ionizing gamma radiation has been shown to reduce neointimal formation and the incidence of restenosis after balloon angioplasty and stenting in clinical trials. However, the long-term effects of this therapy are unknown. The first cohort of patients to receive intracoronary gamma radiation after balloon angioplasty for the prevention of restenosis have completed a 5-year angiographic and clinical follow-up. The outcome of these patients is presented and discussed.


METHODS
Twenty-one patients with unstable angina (22 arteries) underwent standard balloon angioplasty. Intracoronary radiation therapy was performed immediately after the intervention using an Iridium-192 source wire hand-delivered to the angioplasty site. All patients were followed clinically and Quantitative Coronary Analysis (QCA) was performed at 6, 24, 36 and 60 months.


RESULTS
Target lesion revascularization occurred in six lesions, three of which were total occlusions (two early within 30 days and one occurred at 2 years), and one patient had a myocardial infarction attributable to a nontarget vessel. Serial QCA detected a binary restenosis rate of 28.6% (n=6) at 6 months. The late loss (0.29 mm) and loss index (0.25) remained low at 2, 3 and 5 years. Angiographic complications included four aneurysms (two procedure related and two occurring within 3 months). At 2 years, only one aneurysm increased in size (46 vs. 27 mm(2)); and at 3 and 5 years, all aneurysms remained unchanged. No other angiographic complications were observed.


CONCLUSIONS
The early clinical and angiographic effects of intracoronary gamma radiation were maintained at 5 years without further increase in the aneurysm formation or apparent new adverse effects related to the radiation therapy between 2 and 5 years.
Condado
Jose A
JA
Department of Cardiology Hospital Miguel Perez-Carreno, Centro Medico, Caracas, Venezuela.
Waksman
Ron
R
Saucedo
Jorge F
JF
Bhargava
Balram
B
Lansky
Alexandra J
AJ
Calderas
Carlos
C
Gurdiel
Orlando
O
Gonzalez
Juan
J
Fadoul
Merche
M
Parra
Bogart
B
Iturria
Isabel
I
Amezaga
Bingen
B
D000328:Adult; D000368:Aged; D000789:Angina, Unstable / Q000000981:diagnostic imaging* / Q000401:mortality / Q000628:therapy*; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects*; D015331:Cohort Studies; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007322:Instillation, Drug; D007496:Iridium Radioisotopes / Q000008:administration & dosage* / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications; D015996:Survival Rate; D013997:Time Factors
D007496:Iridium Radioisotopes