Table 1. Randomized trials and registries evaluating the role of OCT guidance during BRS implantation.
| Study | Year | Total patients | Total OCT | Timing of follow-up | Device | Struts thickness (µm) | Study results |
|---|---|---|---|---|---|---|---|
| ABSORB-cohort B | 2011 | 101 | 101 (51 at baseline) | 6 and 24 months OR 12 and 36 months | ABSORB everolimus-eluting scaffold (Abbott Vascular, Santa Clara, California, USA) | 156 | No scaffold area reduction, well controlled inhibition of neointima, and almost complete coverage of the struts (97% at 1 year) |
| ABSORB Japan | 2014 | 400 | 125 | 24 months | ABSORB everolimus-eluting scaffold (Abbott Vascular, Santa Clara, California, USA) | 156 | Vessel healing by two-year OCT was nearly complete in both BVS and CoCr-EES arms with almost fully covered struts, and minimal malapposition. The flow area by two-year OCT was smaller in the BVS arm than in the CoCr-EES arm, mainly due to tissue growth inside the device (BVS: –1.49±1.13 mm2 vs. CoCr-EES: –0.80±0.74 mm2, P=0.001) |
| Mattesini et al. | 2014 | 73 | 35 patients with ABSORB BVS (50 lesions) matched with 38 patients with 2nd generation DES (50 lesions) | Post-implantation | ABSORB everolimus-eluting scaffold (Abbott Vascular, Santa Clara, California, USA) | 156 | Incidence of RAS>20% was not statistically significant different in the BVS and DES (P=0.85) and there was no difference in the mean RAS (P=0.32). There was a higher incidence of ISA at the proximal edge in the BVS group (P=0.05) but no difference in the overall percentage of ISA (P=0.62); The mean and minimum eccentricity index and the symmetry index were similar in the two groups; In the BVS group, there was a trend toward a higher prolapse area (P=0.08) but this did not significantly impact on the final lumen area, which was similar in both groups |
| Caiazzo et al. | 2016 | 101 | 65 patients (147 OCT-pullbacks) | Pre and post implantation | ABSORB everolimus-eluting scaffold (Abbott Vascular, Santa Clara, California, USA) | 156 | 49.0% of OCT pullbacks caused a change in strategy during the BVS implantation procedure; OCT-pullbacks pre BVS insertion suggested: need for further pre-dilatation (10.2%); selection of a different scaffold diameter (4.8%); different scaffold length (11.6%); OCT-pullbacks after BVS insertion suggested: the need for a second post-dilatation for scaffold apposition/expansion optimization (18.4%); need for further BVS/stent implantation for incomplete lesion coverage and/or edge dissection (4.1%) |
| Mattesini et al. | 2016 | 72 | 35 patients with ABSORB BVS and 37 matched patients with DESOLVE-150 |
Post-implantation | ABSORB everolimus-eluting scaffold (Abbott Vascular, Santa Clara, California, USA) vs. DESOLVE novolimus-eluting BRS (Elixir Medical Corporation, Sunnyvale, California, USA) | 156 vs. 150 | OCT analysis showed similar MLA (Absorb vs. DESolve: 5.8±1.9 vs. 6.1±2.6 mm2, P=0.43) and mean luminal area (Absorb vs. DESolve: 7.1±2.2 vs. 7.2±1.9 mm2, P=0.77). The mean eccentricity index was 0.85±0.05 with Absorb and 0.80±0.05 with DESolve, P<0.01. There was no difference in the incidence of overall ISA. A smaller prolapse area was found with Absorb (Absorb vs. DESolve 1.0±1.1 vs. 3.6±6.2 mm2, P<0.01) |
| Boeder et al. | 2017 | 60 | 45 patients with DESOLVE-150 and 15 patients with DESOLVE-100 | Post-implantation | DESOLVE novolimus-eluting BRS (Elixir Medical Corporation, Sunnyvale, California, USA) | 100 vs. 150 | OCT showed similar post-procedural scaffold geometry and outcome indicating that both BRS may be implanted with good acute performance. However, the data suggest a decreased radial strength for the 100 μm BRS (minimal lumen area of 6.1±1.9 vs. 5.2±1.6 mm2, P=0.06; mean residual area stenosis was 15.3% vs. 21.3, P=0.22; mean eccentricity index did not differ significantly (0.8±0.1 vs. 0.6±0.1, P=0.61). Prolapse area was 4.5±8.8 vs. 5.6±9.8 mm2) |
| FORTITUDE | 2016 | 62 | 60 | 9 months | FORTITUDE sirolimus-eluting scaffold (Amaranth, Mountain View, CA, USA) | 150 | High levels of strut coverage (96%) and scaffold stability (1.7% late discontinuities) |
| RENASCENT II | 2017 | 60 | 59 | 9 months | APTITUDE sirolimus-eluting scaffold (Amaranth, Mountain View, CA, USA) | 115 | High level of strut coverage (97.0%) and low rate of malapposition (0.037%, all covered) |
| MERES-1 | 2017 | 108 | 108 | 6 months | MeRes 100 BRS (Meril Life Sciences Pvt. Ltd., Vapi, India) sirolimus-eluting BRS | 100 | Minimum scaffold area (6.86±1.73 mm2) and percentage neointimal strut coverage (99.30%) |
| BIOSOLVE-II and -III | 2017 | BIOSOLVE-II, N=123; BIOSOLVE-III, N=61 | 11 | 12 months | DREAMS 2G scaffold (Magmaris; Biotronik, Bülach, Switzerland) sirolimus-eluting scaffold with magnesium alloy | 150 | No intraluminal mass was detected by optical coherence tomography in BIOSOLVE-II at 6 and 12 months and no malapposed struts were detected at six months, when scaffold struts were already well embedded into the vessel wall . With its 95% absorption at 12 months, a late acquired malapposition was unlikely |
OCT, optical coherence tomography; BRS, Bioresorbable vascular scaffold; ISA, impaired scaffold apposition.