Optical Coherence Tomography- Versus Angiography-Guided Magnesium Bioresorbable Scaffold Implantation in NSTEMI Patients

The purpose of a bioresorbable scaffold (BRS) is to provide radial support during coronary healing. In this study, coronary artery healing after optical coherence tomography (OCT)- versus angiography-guided magnesium BRS (MBRS) implantation in patients with non-ST-segment-elevation myocardial infarction (NSTEMI) is compared. 75 patients were randomized 1:1 to OCT- or angiography-guided implantation of a MBRS with protocolled pre- and post-dilation. In the OCT-guided group, prespecified criteria indicating additional intervention were (1) scaffold under-expansion, (2) strut malapposition, (3) edge dissection, and (4) residual stenosis at distal or proximal reference segments. The primary endpoint was OCT-derived healing stage at 6 months. At 6 months, there was no difference in average healing stage between OCT- and angiography-guided intervention (4.6 [interquartile range (IQR): 4.5–4.7] versus 4.5 [IQR: 4.3–4.7]; p = 0.54). The MBRSs were completely resolved in 77.0% [IQR: 68.5–85.5] versus 76.5% [IQR: 67.9–85.5]; (p = 0.97). Minimal lumen area (MLA) was reduced at 6 months in both the OCT- (32.3%; p < 0.01) and the angiography-guided group (21.3%; p < 0.01), however OCT-guided implantation was associated with a greater reduction of total lumen volume (−27.1 ± 32.5 mm3 versus −5.0 ± 32.9 mm3; p < 0.01) and MLA (−2.3 ± 1.6 mm2 vs. −1.4 ± 1.4 mm2; p = 0.02). In NSTEMI patients, OCT-guidance with protocolled pre- and post-dilation of MBRS implantation showed similar healing pattern at 6 months compared to angiography-guidance alone. The Coronary Artery Healing Process after Optical Coherence Tomography Guided Percutaneous Coronary Intervention with Magmaris Bioresorbable Scaffold in Patients with Non-ST-Segment-Elevation Myocardial Infarction: (HONEST) trial is registered with ClinicalTrials.gov, NCT03016624.