Published DEB-AMI Data Do Not Meet Primary Endpoint

April 11, 2012—Initial results of the DEB-AMI (Drug-Eluting Balloon in Acute Myocardial Infarction) trial were published by Anouar Belkacemi, MD, et al online ahead of print in the Journal of the American College of Cardiology.

The results were first presented in November 2011 at the Cardiovascular Research Foundation's annual Transcatheter Cardiovascular Therapeutics scientific symposium in San Francisco. The presentation was summarized at that time in Cardiac Interventions Today.

According to the DEB-AMI investigators, the goal of this study was to compare angiographic imaging, intravascular imaging, and functional parameters, as well as the clinical outcomes of patients treated with drug-eluting balloons (DEB) plus bare-metal stents (BMS) versus BMS alone versus drug-eluting stents (DES) for ST-segment elevated acute myocardial infarction (STEMI).

The investigators noted that concerns remain regarding the long-term safety of DES in the treatment of STEMI and that DEB could provide an attractive alternative with potentially similar effectiveness but limiting the long-term hazards related to late-acquired stent malapposition and thus stent thrombosis.

As detailed in the Journal of the American College of Cardiology, DEB-AMI was a randomized, international, two-center, single-blinded, thee-arm study. STEMI patients were randomly assigned to group A (BMS), group B (DEB plus BMS), or group C (DES) after successful thrombus aspiration. The primary endpoint was 6-month angiographic in-stent late-luminal loss. Secondary endpoints were in-stent binary restenosis and major adverse cardiac events (cardiac death, myocardial infarction, and target vessel revascularization). In a subgroup of patients, stent apposition (by optical coherence tomography) and endothelial function (by acetylcholine infusion) was assessed.

The investigators found that in the 150 patients who were randomized in the study, procedural success was achieved in 96.7%. In groups A, B, and C, respectively, late-luminal loss was 0.74 ± 0.57 mm, 0.64 ± 0.56 mm, and 0.21 ± 0.32 mm (P < .01); binary restenosis was 26.2%, 28.6%, and 4.7% (P = .01); and major adverse cardiac event rates were 23.5%, 20%, and 4.1% (P = .02), respectively. The median percentage of uncovered and malapposed stent struts per lesion was 0 (0–0.35), 2.84 (0–6.63), and 5.21 (3.25–14.5) (P < .01). Significant paradoxical vasoconstriction was seen in groups B and C.

These findings demonstrated that in STEMI patients, DEB followed by BMS implantation failed to show angiographic superiority to BMS alone. Angiographic results of DES were superior to both BMS and DEB. Moreover, DEB before implantation induced more uncovered and malapposed stent struts than BMS, but less than after DES, concluded the investigators.

According to the Cardiovascular Research Foundation, although the DEB group did not meet the primary endpoint of reduced late lumen loss, the study investigators noted that the experience of the operators and discrepancies between the two trial sites may have affected the findings.