Long-Term Results of Bioresorbable Vascular Scaffolds in Patients With In-Stent Restenosis: The RIBS VI Study.

BACKGROUND: In patients with in-stent restenosis (ISR) bioresorbable vascular scaffolds (BVS) provide similar results to drug-coated balloons (DCBs) but are inferior to drug-eluting stents (DES) at 1 year. However, the long-term efficacy of BVS in these patients remains unknown. OBJECTIVES: This study sought to assess the long-term safety and efficacy of BVS in patients with ISR. METHODS: RIBS VI (Restenosis Intrastent: Bioresorbable Vascular Scaffolds Treatment; NCT02672878) and RIBS VI Scoring (Restenosis Intrastent: Bioresorbable Vascular Scaffolds Treatment With Scoring Balloon; NTC03069066) are prospective multicenter studies designed to evaluate the results of BVS in patients with ISR (N = 220). The inclusion and exclusion criteria were identical to those used in the RIBS IV (ISR of DES) (Restenosis Intra-stent of Drug-eluting Stents: Drug-eluting Balloon vs Everolimus-eluting Stent; NCT01239940) and RIBS V (ISR of bare-metal stents) (Restenosis Intra-stent of Bare Metal Stents: Paclitaxel-eluting Balloon vs Everolimus-eluting Stent; NCT01239953) randomized trials (including 249 ISR patients treated with DCBs and 249 ISR patients treated with DES). A prespecified comparison of the long-term results obtained with these treatment modalities (ie, DES, DCBs, and BVS) was performed. RESULTS: Clinical follow-up at 3 years was obtained in all (100%) 718 patients. The 3-year target lesion revascularization rate after BVS was 14.1% (vs 12.9% after DCBs [not significant], and 5.2% after DES [HR: 2.80; 95% CI: 1.47-5.36; P = 0.001]). In a landmark analysis (>1 year), the target lesion revascularization rate after BVS was higher than after DES (adjusted HR: 3.41; 95% CI: 1.15-10.08) and DCBs (adjusted HR: 3.33; 95% CI: 1.14-9.70). Very late vessel thrombosis was also more frequent with BVS (BVS: 1.8%, DCBs: 0.4%, DES: 0%; P = 0.03). CONCLUSIONS: In patients with ISR, late clinical results of DES are superior to those obtained with DCBs and BVS. Beyond the first year, DCBs are safer and more effective than BVS.

Compromiso de vasos secundarios durante la implantación directa de stent coronario: Incidencia y factores relacionados / Side branch occlusion during direct stent implantation: Incidence and related factors

Objetivo: El objetivo fue evaluar el grado de compromiso de las ramas que son enjauladas durante la implantación directa de stent. Pacientes y métodos: Se estudiaron 56 pacientes en los que se implantó al menos un stent coronario (58 stents) sin dilatación previa con balón y en los que se enjauló alguna rama secundaria. Se evaluó la tasa de pérdida de la rama, el efecto de la implantación del stent sobre el flujo de esta rama y los factores relacionados con estos hechos. Resultados: El vaso principal fue la descendente anterior en el 63%, la circunfleja en el 21%, la coronaria derecha en el 14% y el tronco principal de la coronaria izquierda en un caso. Se obtuvo éxito angiográfico sobre el vaso principal en todos los casos. Antes del procedimiento, el flujo a nivel de la rama secundaria era TIMI grado 3, 2 y 0 en 55 (95%), 2 (3%) y un caso (2%), respectivamente. Tras la implantación del stent, el flujo era TIMI grado 3, 2, 1 y 0 en 50 (86%), 1 (2%), 2 (3%) y 5 (9%) casos, respectivamente (p = 0.204). La incidencia de pérdida de la rama fue 12% (7/58); en un caso, se intentó con éxito recanalizar y dilatar ésta a través de los struts del stent, por lo que la tasa de pérdida de rama final fue 10% (6/ 58). Las ramas que se ocluyeron tenían un mayor grado de estenosis en el origen antes de la implantación del stent (30.2 ± 31.3% vs 16.8 ± 11.1%, p = 0.028). En los pacientes que se reevaluaron angiográficamente, a los 6.2 ±1.9 meses, el 50% de las ramas que se habían ocluido se encontraban permeables, y el 88% de las que no se comprometieron seguían permeables. Conclusiones: La tasa de oclusión de las ramas con la implantación directa de stent fue 12% en nuestra serie, cifra similar a la que ocurre con la implantación de stent tras dilatación con balón. Por tanto, la existencia de ramas localizadas en el segmento en el que va a implantarse el stent no tiene por qué condicionar la decisión o no de realizar una dilatación previa con balón.

Aim: The aim of the study was to evaluate the compromise of side branches when jailed by a coronary stent implanted without balloon predilation. Patients and methods: 56 patients in which at least a coronary stent was implanted without balloon predilation and covering a side brach (58 stents, 1.04 ± 0.19 per patient) were studied. The effect of direct coronary stent implantation over side branch flow, as well as the characteristics associated were studied. Results: The main vessel was left anterior descending in 63%, left circumflex in 21%, right coronary in 14%, and left main in one case. An angiographic successful result in the main vessel was obtained in all cases. Coronary flow was TIMI 3, 2, 1, and 0 in 95%, 3%, 0%, and 2% before the procedure, in comparison with 86%, 2%, 3%, and 9% after stent implantation (p = 0.204). The incidence of side branch occlusion was 12% (7/58). In one case, the side branch was dilated across the stent struts, and thus the rate of side branch loss at the end of the procedure was 10% (6/58). In cases of side branch occlusion, there was a more severe stenosis at its origin before stent implantation (30.2 ± 31.3% vs 16.8± 11.1%, p = 0.028). Fifty percent of side branches occluded after direct coronary stent implantation and angiographically reevaluated at follow-up became patent, and 88% of side branches not affected after stent implantation remained patent at 6.2 ± 1.9 months. Conclusion: The rate of side branch occlusion after direct stent implantation in our series was 12%, that is not different from that reported for conventional stent implantation. Thus, the decision of using direct or conventional coronary stenting should not be conditioned by the presence of side branches arising from the target lesion.