Five-year clinical follow-up after intracoronary radiation: results of a randomized clinical trial.
BACKGROUND
Several clinical trials indicate that intracoronary radiation is safe and effective for treatment of restenotic coronary arteries. We previously reported 6-month and 3-year clinical and angiographic follow-up demonstrating significant decreases in target lesion revascularization (TLR) and angiographic restenosis after gamma radiation of restenotic lesions. The objective of this study was to document the clinical outcome 5 years after treatment of restenotic coronary arteries with catheter-based iridium-192 (192Ir).


RESULTS
A double-blind, randomized trail compared 192Ir to placebo sources in patients with restenosis after coronary angioplasty. Over a 9-month period, 55 patients were enrolled; 26 were randomized to 192Ir and 29 to placebo. At 5-year follow-up, TLR was significantly lower in the 192Ir group (23.1% versus 48.3%; P=0.05). There were 2 TLRs between years 3 and 5 in patients in the 192Ir group and none in patients in the placebo group. The 5-year event-free survival rate (freedom from death, myocardial infarction, or TLR) was greater in 192Ir-treated patients (61.5% versus 34.5%; P=0.02).


CONCLUSIONS
Despite apparent mitigation of efficacy over time, there remains a significant reduction in TLR at 5 years and an improvement in event-free survival in patients treated with intracoronary 192Ir. The early clinical benefits after intracoronary gamma radiation with 192Ir seem durable at 5-year clinical follow-up.
Grise
Mark A
MA
Division of Cardiovascular Diseases, Scripps Clinic, La Jolla, Calif 92037, USA.
Massullo
Vincent
V
Jani
Shirish
S
Popma
Jeffrey J
JJ
Russo
Robert J
RJ
Schatz
Richard A
RA
Guarneri
Erminia M
EM
Steuterman
Stephen
S
Cloutier
David A
DA
Leon
Martin B
MB
Tripuraneni
Prabhakar
P
Teirstein
Paul S
PS
D000368:Aged; D001918:Brachytherapy; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D003326:Coronary Circulation; D023903:Coronary Restenosis / Q000097:blood / Q000175:diagnosis / Q000532:radiotherapy*; D018572:Disease-Free Survival; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D005720:Gamma Rays; D006801:Humans; D007496:Iridium Radioisotopes / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D009389:Neovascularization, Pathologic; D015607:Stents / Q000009:adverse effects; D016896:Treatment Outcome
D007496:Iridium Radioisotopes