APICE-OCT: EES, ZES Yield Low Rates of Uncovered Struts in ACS

SAN FRANCISCO, CALIF.—A small study suggested that the new generation of DES has a very low incidence of uncovered or malapposed struts in patients with ACS. The study found no difference between zotarolimus-eluting and everolimus-eluting stents.

“It has been reported that uncovered stent struts were more frequent with first-generation DES and in the clinical setting of ACS,” said Alaide Chieffo, MD, of the San Raffaele Scientific Institute in Milan. She added that this was the first study comparing stent strut coverage rates in ACS patients treated with second-generation EES (Promus Element, Boston Scientific) or ZES (Endeavor Resolute, Medtronic).

The APICE-OCT study randomized 60 ACS patients at four centers in Italy to either of the two devices. Optical coherence tomography showed that 6.5% of stent struts in EES-treated  and 6.8% of stent struts in ZES-treated lesions were uncovered at 6 months. There were also low rates of malapposed struts both with and without neointimal coverage, in both stent groups (see Table).

There were no differences between the two groups with regard to baseline characteristics including age, rates of diabetes and hypertension, and left ventricular ejection fraction. Both groups had an average number of lesions treated of 1.2; the average stent length was 29.7 mm in the EES group and 32.2 mm in the ZES group. After 30 days of clinical follow-up there was one sudden cardiac death, which occurred 8 days after the initial procedure; there were no other MACE at 30 days. Twenty-four EES lesions and 25 ZES lesions were available for 6-month follow-up; at that point, there were four MACE reported in the EES group and one in the ZES group (P=.139). Volumetric analyses performed with OCT showed no differences between the stents in neointima volume or other measures.

“Both EES and ZES are associated with a very low rate of uncovered and/or malapposed struts, even in this particular setting of ACS,” Chieffo said.