Real-world clinical practice of intracoronary radiation therapy as compared to investigational trials.
Intracoronary radiation therapy (IRT) is well established in clinical practice as an effective treatment for in-stent restenosis. We aimed to determine if the 6-month clinical outcome of patients treated postapproval for marketing [commercial radiation (CR)] is equivalent to those patients enrolled in the Washington Radiation for In-Stent Restenosis Trials [Gamma WRIST and Beta WRIST; investigational radiation (IR)]. The 6-month clinical outcome of 110 consecutive patients with 125 lesions who received IRT (gamma, (192)Ir, 15-18 Gy, n = 6; or beta, (32)P, 20 Gy, n = 20; or (90)Sr/Y, 18.4-23.0 Gy, n = 99) in CR was compared with the 6-month clinical outcome of 117 patients with 117 lesions who received IRT ((192)Ir, 15 Gy, n = 65, in Gamma WRIST; and (90)Y, 20.6 Gy, n = 52, in Beta WRIST) in IR. Patients in CR were treated with wider radiation margins. The CR received antiplatelet therapy for at least 6 months and the IR for 1 month. The baseline characteristics of both groups were similar. Use of atheroablation devices was less in CR than IR (15.2% vs. 32.8%, respectively; P = 0.001). The overall major adverse cardiac events (death, Q-wave myocardial infarction, and target vessel revascularization; 18.2% vs. 29.1% in IR; P = 0.05) were significantly lower in the CR when compared with patients in the IR. The real-world clinical practice of IRT demonstrates lower events and better clinical outcomes. This is most likely a result of implementation of the lessons learned from the clinical trials such as optimizing the dosimetry by using a higher dose, treating wider margins to minimize edge effect, and administering prolonged antiplatelet therapy to abolish late thrombosis.
Rha
Seung-Woon
SW
Department of Internal Medicine, Washington Hospital Center, Washington, DC 20010, USA.
Kuchulakanti
Pramod K
PK
Pakala
Rajbabu
R
Pichard
Augusto D
AD
Satler
Lowell F
LF
Kent
Kenneth M
KM
Suddath
William O
WO
Pinnow
Ellen
E
Torguson
Rebecca
R
Chan
Rosanna C
RC
Deible
Regina
R
Lindsay
Joseph
J
Waksman
Ron
R
D000368:Aged; D001610:Beta Particles / Q000627:therapeutic use; D001918:Brachytherapy / Q000379:methods*; D002986:Clinical Trials as Topic; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000532:radiotherapy*; D003328:Coronary Thrombosis; D003331:Coronary Vessels / Q000528:radiation effects; D005260:Female; D005720:Gamma Rays / Q000627:therapeutic use; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D016896:Treatment Outcome
D010975:Platelet Aggregation Inhibitors