Paris, France - In what smacks of a one-step-forward, two-steps-back strategy in the battle against restenosis, a group of German researchers has taken the unusual approach of dispensing with stents altogether for the treatment of in-stent restenosis (ISR) and returning to plain old balloon angioplasty, with a twist. Presenting the first-in-man (FIM) results from the PACCOCATH ISR I study here at the EuroPCR 2005 meeting, Dr Bruno Scheller (Universitätsklinikum des Saarlandes, Homburg/Saar, Germany) explained that the method he and his coinvestigators are evaluating involves the use of a paclitaxel-coated angioplasty balloon.

Drug-eluting stents have proven themselves effective in de novo restenosis, but the use of a "stent-in-stent approach" for cases of ISR is "less desirable," Scheller explained. Animal studies have suggested that the benefit of paclitaxel can still be exploited without the need for a second stent.

In PACCOCATH ISR I, Scheller and colleagues evaluated the safety and efficacy of a paclitaxel-coated PTCA catheter (3 µg paclitaxel/mm^² balloon surface) in comparison with a conventional PTCA catheter in patients undergoing repeat PTCA for coronary ISR. As Scheller told his EuroPCR audience, this FIM study enrolled 52 patients who were then followed for six months.

At follow-up, late lumen loss in segment was significantly lower in the paclitaxel-coated balloon group, as was binary restenosis. While there were no deaths in either group, the target lesion revascularization (TLR) rate was 0 in the paclitaxel group, compared with 24% in the uncoated-balloon group.

PACCOCATH ISR I: Main results

End point	Paclitaxel-coated balloon	Plain balloon	p
Late lumen loss (mm)*	0.13	0.82	0.002
Binary restenosis (%)	8.7	40.9	0.017
TLR (%)	0	24	0.009

Clearly, said Scheller, the PACCOCATH approach will also need to be tested against drug-eluting stents for ISR. Of note, however, in ISAR DESIRE, which examined drug-eluting stents for ISR, in-segment late loss following implantation of the Taxus stent was 0.55 mm and 0.32 mm for the Cypher, both higher than the 0.13 mm seen in the PACCOCATH ISR I study. Should further evaluation of the approach provide consistently favorable results, the drug-coated balloon could also be valuable in other settings in which metal stents are undesirable, including small vessels and bifurcations, Scheller said.

Commenting on the study for heartwire, Dr Alec Vahanian (Bichat Hospital, Paris, France) called the results "surprising" and "provocative," although very preliminary.

"It's a new concept, and the results are impressive, but this is only a first-in-man study, so it is difficult to make a statement on the results."