BASKET-SMALL 2 Angiographic Substudy Supports Safety of DCBs in Small Coronary Vessels

PARIS, France—In patients with small-vessel coronary artery disease, using a drug-coated balloon (DCB) appears safe and comparable to DES implantation, with favorable angiographic outcomes out to 1 year, according to new data from the BASKET-SMALL 2 trial.

“We did an all-comer clinical trial with event-driven angiographies, so the angiographies did not influence event rates as they [have] in other trials,” Raban Jeger, MD (University Hospital Basel, Switzerland), reported here at EuroPCR 2019.

The main BASKET-SMALL 2 trial was conducted at 14 centers in Germany, Switzerland, and Austria. The open-label, noninferiority trial included 758 patients with small de novo coronary lesions that were at least 2 mm but < 3 mm in diameter. All lesions were predilated and a successful result, characterized as absence of flow-limiting dissections and residual stenosis < 30%, was a requirement for randomization.

Patients were randomized to undergo PCI with the SeQuent Please paclitaxel-coated balloon (B. Braun Melsungen) or one of two second-generation DES. The comparator was the paclitaxel-eluting Taxus Element (Boston Scientific) initially and then later the everolimus-eluting Xience stent (Abbott). Patients in the DCB group received dual antiplatelet therapy (DAPT) for 4 weeks, whereas those in the DES group received DAPT for 6 weeks if they did not have ACS or 1 year if they did have ACS. At 1 year, the rate of MACE was 7.33% in the DCB group and 7.45% in the DES group, a difference that met criteria for noninferiority (P = 0.0152)

The new prespecified analysis, presented here in a late-breaking clinical trial session, looked at clinically indicated angiography, which was performed in 64 patients in the DES group and 47 patients in the DCB group. At a mean follow up of 6 months, minimal lumen diameter in-stent and in-balloon was better with DES compared with DCB (1.76 vs 1.35 mm) and diameter stenosis remained larger in the DCB group (34.5% vs 18.8%; P < 0.001 for both). Late lumen loss, however, was similar in both groups.

"One of the striking findings here is that there were eight complete thrombotic vessel occlusions in the DES patients and none in the drug-coated balloon patients,” Jeger noted during a press conference after his presentation. "In our opinion, this corroborates the safety of the DCB-only strategy in small coronary artery disease and adds to ongoing discussion about the safety of this technique.” However, Jeger acknowledged that the strategy is not for all small lesions, noting, "I'm still a user of stents."

Unanswered Questions

Trying to understand why the eight stent thromboses occurred, panelist Hany Eteiba, MD (Royal College of Physicians and Surgeons of Glasgow, Scotland), questioned whether the sizing of the vessels was accurate. Possibly, he hypothesized, the investigators "might be undersizing the stent for the vessel and therefore your stent thrombosis [rates] might be higher than expected."

Jeger said his group has had multiple discussions about what constitutes a "small vessel" and admitted that without IVUS it is difficult to know what differences, if any, may have been present in those vessels that occluded.

To TCTMD, Jeger said there is a learning curve for using DCBs in small vessels. “The trial was done in centers with operators who were knowledgeable about the technique,” he said. “I think the results here represent the results of experienced interventional cardiologists. We had good stent implanters.”

As for whether the study is practice-changing, Jeger said that in his center "all the DES believers slowly switched to the other side. The results are good and we [think] that this could add to current techniques.”

But Panelist Petr Kala, MD, PhD (University Hospital Brno, Czech Republic), seemed less impressed, noting that in his opinion the lesion types were "simple." Jeger countered, however, that a significant portion of patients in both groups were high risk, with many having diabetes and ACS. Panelists also asked about the 125 patients from the main trial who had an unsuccessful predilatation and were not randomized. Data from those registry patients will be presented at a later date, Jeger said.