Real-world clinical practice of intracoronary radiation therapy as compared to investigational trials

• Published in: Catheterization and cardiovascular interventions 2005-01, Vol.64 (1), p.61-66
• Main Authors: Rha, Seung-Woon, Kuchulakanti, Pramod K., Pakala, Rajbabu, Pichard, Augusto D., Satler, Lowell F., Kent, Kenneth M., Suddath, William O., Pinnow, Ellen, Torguson, Rebecca, Chan, Rosanna C., Deible, Regina, Lindsay, Joseph, Waksman, Ron
• Format: Article
• Language: English
• Subjects: Aged; Beta Particles - therapeutic use; brachytherapy; Brachytherapy - methods; Clinical Trials as Topic; Coronary Angiography; Coronary Restenosis - radiotherapy; Coronary Thrombosis; Coronary Vessels - radiation effects; Female; Gamma Rays - therapeutic use; Humans; Logistic Models; Male; Middle Aged; Platelet Aggregation Inhibitors - therapeutic use; Radiotherapy Dosage; restenosis; revascularization; Treatment Outcome
• ISSN: 1522-1946; 1522-726X
• DOI: 10.1002/ccd.20234

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, 192Ir, 15–18 Gy, n = 6; or beta, 32P, 20 Gy, n = 20; or 90Sr/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 (192Ir, 15 Gy, n = 65, in Gamma WRIST; and 90Y, 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. Catheter Cardiovasc Interv 2005;64:61–66. © 2004 Wiley‐Liss, Inc.