COMFORTABLE AMI: Biolimus-Eluting Stent Bests BMS in STEMI

San Francisco, CA—Compared with bare-metal stents (BMS), a bioabsorbable polymer-based biolimus-eluting stent (BES) significantly reduced the incidence of MACE at 2 years in the COMFORTABLE AMI study, according to data presented at TCT 2013.

Lorenz Räber, MD, of Bern University Hospital in Switzerland, and colleagues, looked at efficacy and safety of the Biomatrix stent (Biosensors, Morges, Switzerland) vs. BMS in 103 STEMI patients from five international centers.

Significant reduction in MACE

Overall, the absolute risk reduction in MACE, the primary outcome, was 6.1% with BES compared with BMS, which was “highly significant,” according to Räber (HR 0.48; 95% CI 0.31-0.72; P=.0005). “Looking at the landmark analysis at 1 year, we noted that the benefit of BES over BMS continued to accrue during the second year of follow-up, resulting in similar risk reduction during the second year,” he added.

Secondary endpoints

Results indicated no significant difference between the two stents in terms of cardiac death (HR 0.69; 95% CI 0.37-1.27; P=.23). However, BES yielded reductions in the composite of target-vessel MI (TV-MI) and cardiac death (HR 0.58; 95% CI 0.35-0.97; P=.036) and clinically indicated target lesion revascularization (TLR; HR 0.36; 95% CI 0.21-0.63; P=.0003) along with a 63% decrease in TV-MI (HR 0.37; 95% CI 0.15-0.87; P=.023) compared with BMS.

“The lower TLR rates are explained by less neointimal hyperplasia with the BES,” Räber said.

Aspirin adherence through 2 years was 96.4% in the BES group and 94.4% for BMS. “We also noted a drop in terms of [dual antiplatelet therapy (DAPT)] intake from approximately 90% to approximately 18% at 2 years without any significant differences between groups with respect to the individual drug,” he said.

At 2 years, definite stent thrombosis rates were 1.4% for BES vs. 2.6% for BMS (HR 0.52; 95% CI 0.23-1.26; P=0.15). “When looking at the landmark analysis at 1 year, the time point at which most patients stopped DAPT, there was no difference in terms of very late stent thrombosis,” Räber said.

Thirteen-month OCT and IVUS imaging study results indicated neointimal thickness of 70 µm for BES vs. 270 µm for BMS (P<.001). The ratio of uncovered struts at the same time point was 2.1% for BES and 0.1% for BMS (OR 16.2; 95% CI 4.6-56.8; P<.001).

The proportion of cross-sections with atherothrombotic material was significantly lower with BES compared with BMS (P=.0013).

“There was a low and similar frequency of malapposed struts at 13 months,” Räber said. “Also, we observed no evidence for positive vessel remodeling with BES.”

Disclosures:

Räber reports no relevant conflicts of interest.