Objectives: We studied the efficacy of intracoronary brachytherapy (ICB) after successful coronary stenting in diabetic patients with de novo lesions.
Background: Intracoronary brachytherapy has proven effective in preventing recurrences in patients with in-stent restenosis. However, the role of ICB for the treatment of de novo coronary stenoses remains controversial.
Methods: Ninety-two patients were randomized to either ICB or no radiation after stenting. Primary end points were in-stent mean neointimal area (primary end point of efficacy) and minimal luminal area of the entire vessel segment (primary end point of effectiveness), as assessed by intravascular ultrasound at six-month follow-up. Quantitative coronary angiography analysis was performed at the target, injured, irradiated, and entire vessel segments.
Results: At follow-up, the in-stent mean neointimal area was 52% smaller in the ICB group (p < 0.0001). However, there was no difference in the minimal luminal area of the vessel segment (4.5 +/- 2.4 mm2 vs. 4.4 +/- 2.1 mm2). Restenosis rates increased progressively by the analyzed segment in the ICB group: target (7.1% vs. 20.9%, p = 0.07), injured (9.5% vs. 20.9%, p = NS), irradiated (14.3% vs. 20.9%, p = NS), and vessel segment (23.8% vs. 25.6%, p = NS). At one year, 1 cardiac death, 6 myocardial infarctions (MIs) (3 due to late stent thrombosis), and 10 target vessel revascularizations (TVRs) (6 due to the edge effect) occurred in the ICB group, whereas in the nonradiation group, there were 11 TVRs and no deaths or MIs.
Conclusions: Intracoronary brachytherapy significantly inhibited in-stent neointimal hyperplasia after stenting in diabetic patients. However, clinically this was counteracted by the occurrence of the edge effect and late stent thrombosis.