Bioadaptor implant versus contemporary drug-eluting stent in percutaneous coronary interventions in Sweden (INFINITY-SWEDEHEART): a single-blind, non-inferiority, registry-based, randomised controlled trial.

BACKGROUND

Persistent non-plateauing adverse event rates in patients who underwent percutaneous coronary intervention (PCI) remain a challenge. A bioadaptor is a novel implant that addresses this issue by restoring the haemodynamic modulation of the artery, allowing cyclic pulsatility, vasomotion, and adaptative remodelling, by unlocking and providing dynamic support to the artery. We aimed to assess outcomes with the device versus a contemporary drug-eluting stent (DES) in a representative PCI population.

METHODS

INFINITY-SWEDEHEART is a single-blind, non-inferiority, registry-based, randomised controlled study conducted in 20 hospitals in Sweden. Patients aged 18-85 years, with chronic or acute coronary syndrome ischaemic heart disease, with an indication for PCI, with up to three de novo lesions suitable for implantation with one single device per lesion, and successful pre-dilatation were identified via the Swedish Coronary Angiography and Angioplasty Registry and eligible for enrolment. Participants were randomly assigned (1:1), using block randomisation with random variation in block size and stratified by site, to either the DynamX bioadaptor (Elixir Medical, Milpitas, CA, USA) or a zotarolimus-eluting DES (Resolute Onyx and Onyx Trustar, Medtronic, Minneapolis, MN, USA). The primary endpoint was the device-oriented clinical endpoint of target lesion failure at 12 months (a composite of cardiovascular death, target vessel myocardial infarction, and ischaemia-driven target lesion revascularisation), assessed in the intention-to-treat (ITT) population (ie, all patients randomly assigned to treatment, regardless of treatment received) who had either experienced an event up to 12 months or completed the trial up to 12 months. Non-inferiority was established if the upper limit of the two-sided 95% CI for the absolute risk difference was less than 4·2%. Powered secondary endpoints were landmark analyses from 6 months onwards for target lesion failure, target vessel failure (composite of cardiovascular death, target vessel myocardial infarction, and ischaemia-driven target vessel revascularisation), and target lesion failure for patients with acute coronary syndrome assessed in the ITT population). This study is registered with ClinicalTrials.gov, NCT04562805, and follow-up to 5 years is ongoing.

FINDINGS

Between Sept 30, 2020, and July 11, 2023, 2399 patients were randomly assigned to receive the bioadaptor (n=1201) or DES (n=1198; ITT population). Median age was 69·5 years (IQR 61·2-75·6), 575 (24·0%) of 2399 patients were female, and 1824 (76·0%) were male (data on race and ethnicity were not collected), and 1838 (76·6%) patients presented with acute coronary syndrome. The primary endpoint of 12-month target lesion failure occurred in 28 (2·4%) of 1189 assessable patients in the bioadaptor group versus 33 (2·8%) of 1192 assessable patients in the DES group, with a risk difference of -0·41% (95% CI -1·94 to 1·11; p<0·0001). In the prespecified landmark analysis from 6 months to 12 months, the Kaplan-Meier estimates of target lesion failure were 0·3% (with events in three of 1170 patients) in the bioadaptor group versus 1·7% (with events in 16 of 1176 patients) in the DES group (hazard ratio 0·19 [95% CI 0·06 to 0·65]; p=0·0079), of target vessel failure were 0·8% (events in eight of 1167) versus 2·5% (events in 23 of 1174; 0·35 [0·16 to 0·79]; p=0·011), and of target lesion failure in patients with acute coronary syndrome were 0·3% (events in two of 906) versus 1·8% (events in 12 of 895; 0·17 [0·04 to 0·74]; p=0·018). The rate of definite or probable device thrombosis, which was recorded as a safety outcome, was low and did not differ between groups (eight [0·7%] of 1201 in the bioadaptor group vs six [0·5%] of 1198 in the DES group; difference in event rates of 0·16% [95% CI -0·50 to 0·83]).

INTERPRETATION

Among patients with coronary artery disease, including those with acute coronary syndrome, treatment with the bioadaptor was non-inferior to contemporary DES, showing potential to mitigate non-plateauing device-related events and improving outcomes in patients undergoing PCI. The additional planned follow-up will help to reinforce the clinical significance of the 1-year findings.

FUNDING

Elixir Medical.