Paclitaxcel-coated balloon plus bare metal stent vs. sirolimus-eluting stent in de novo lesions: an IVUS study

Restenosis after PCI and/or stent implantation is still one of the challenging problems in the field of interventional cardiology. Different approaches to prevent and to treat restenosis include the use of drug-eluting stents, which have shown to reduce restenosis. Another approach is the treatment with drug-coated balloons. This approach has been proven for different indications, e.g., in-stent restenosis and treatment of peripheral artery disease.

Patients from the PEPCAD III multicentre randomised trial in two study centres (Homburg and Hannover, Germany) were asked to participate in this intravascular ultrasound (IVUS) study at nine-month follow-up. At baseline (nine months before), patients were randomly assigned to receive either a paclitaxel-coated balloon (drug-coated balloon [DCB]) plus a premounted bare metal stent (DCB/BMS) or a sirolimus-eluting stent (drug-eluting stent [DES]) to treat de novo lesions. IVUS at follow-up was performed in order to analyse the restenosis for potential understanding of the mechanism leading to restenosis. IVUS data is available for 55 patients; 26 patients were treated with Cypher(®) DES (Cordis, Miami Lakes, FL, USA) and 29 patients with DCB/BMS. A focal malapposition of the stent was seen in six patients; four after DES and two after DCB/BMS. Stent expansion, calculated as symmetric expansion index, was equal for both groups (0.89 and 0.90). Mean stent area was also equal for both groups (6.25 ± 1.7 vs. 5.65 ± 1.5 mm(2), p=n.s.). The neointimal hyperplasia (calculated as stent area minus lumen area) was significantly different between both groups (0.69 ± 0.49 [DES] vs. 1.08 ± 0.53 mm(2) [DCB/BMS], p<0.01). This resulted in a significantly higher in-stent restenosis in the DCB/BMS group (19.7 vs. 11 %, p<0.01). There is no evidence of geographical mismatch.

First IVUS insights for the DCB/BMS showed a comparable, low incidence of malapposition for the combination of drug-coated balloon and premounted bare metal stent compared to the DES, and stent expansion was good and comparable to DES. However, at nine-month follow-up, the combination of drug-coated balloon and premounted bare metal stent showed higher in-stent restenosis compared to sirolimus DES. Geographical mismatch can be excluded as a reason for this result.