Cardiac Computed Tomography Angiography Follow-Up of Resorbable Magnesium Scaffolds

Introduction: An ancillary advantage of bioresorbable scaffolds is the possibility of non-invasive imaging assessment of the treated coronary segment. Cardiac computed tomography angiography (CCTA) studies of resorbable magnesium scaffolds (RMS) are scarce.

Methods: In this collaborative, international study, nine patients who had an RMS implanted underwent CCTA as part of follow-up assessment. Core-lab blinded quantitative and qualitative assessment was performed by an independent CCTA investigator.

Results: Eight studies were amenable for quantitative analysis, and the blinded CT investigator successfully located and evaluated patency of RMS in all cases. The CCTA follow-up in-scaffold percentage diameter stenosis and area stenosis was 22.2% (12.4-30) and 39.1% (0.23-0.50), in keeping with mild in-scaffold late loss and underlying plaque growth. Moreover, a detailed coronary plaque characterization at treated segments was feasible (fibrous plaque in 69.9%, fibrofatty in 17.13%, necrotic in 4.78% and calcium in 5.72%). As in 6 out of 8 cases, the presentation was an acute coronary syndrome, these preliminary results could suggest plaque stabilization and a good coronary vessel healing with RMS.

Conclusion: Non-invasive, follow-up assessment of RMS with CCTA is feasible. Further CCTA studies for either clinical or research purposes with the present and upcoming generation of resorbable magnesium scaffolds are warranted.