Drug-Eluting Resorbable Scaffold versus Angioplasty for Infrapopliteal Artery Disease.

BACKGROUND: Among patients with chronic limb-threatening ischemia (CLTI) and infrapopliteal artery disease, angioplasty has been associated with frequent reintervention and adverse limb outcomes from restenosis. The effect of the use of drug-eluting resorbable scaffolds on these outcomes remains unknown. METHODS: In this multicenter, randomized, controlled trial, 261 patients with CLTI and infrapopliteal artery disease were randomly assigned in a 2:1 ratio to receive treatment with an everolimus-eluting resorbable scaffold or angioplasty. The primary efficacy end point was freedom from the following events at 1 year: amputation above the ankle of the target limb, occlusion of the target vessel, clinically driven revascularization of the target lesion, and binary restenosis of the target lesion. The primary safety end point was freedom from major adverse limb events at 6 months and from perioperative death. RESULTS: The primary efficacy end point was observed (i.e., no events occurred) in 135 of 173 patients in the scaffold group and 48 of 88 patients in the angioplasty group (Kaplan-Meier estimate, 74% vs. 44%; absolute difference, 30 percentage points; 95% confidence interval [CI], 15 to 46; one-sided P<0.001 for superiority). The primary safety end point was observed in 165 of 170 patients in the scaffold group and 90 of 90 patients in the angioplasty group (absolute difference, -3 percentage points; 95% CI, -6 to 0; one-sided P<0.001 for noninferiority). Serious adverse events related to the index procedure occurred in 2% of the patients in the scaffold group and 3% of those in the angioplasty group. CONCLUSIONS: Among patients with CLTI due to infrapopliteal artery disease, the use of an everolimus-eluting resorbable scaffold was superior to angioplasty with respect to the primary efficacy end point. (Funded by Abbott; LIFE-BTK ClinicalTrials.gov number, NCT04227899.).

Comparison of Angiographic and Intravascular Ultrasound Vessel Measurements in Infra-Popliteal Endovascular Interventions: The Below-the-Knee Calibration Study.

BACKGROUND: Endovascular revascularization (ER) via percutaneous transluminal angioplasty (PTA) and stenting are viable options for revascularization in below-the-knee (BTK) peripheral arterial disease. Two-dimensional angiography has been the standard of practice for estimating vessel size and selecting treatment devices during ER. However, in other vascular territories, intravascular ultrasound (IVUS) offers better visualization of the lumen dimensions. PURPOSE: To compare angiographic and intravascular ultrasound reference vessel (lumen) measurements in below-the-knee peripheral artery interventions. METHODS: Twenty consecutive patients were enrolled in the BTK Calibration study from 2 sites in the United States and Australia. Patients with at least one diseased segment in a native infra-popliteal artery (below-the-knee) and a clinical indication for endovascular therapy (EVT) were included with no limitations with regard to vessel diameter or lesion length. Digital subtraction angiography and IVUS imaging were collected pre- and post-PTA and images were sent to an independent core lab for standardized quantitative analysis of the normal-looking reference vessel dimensions when available. The results were presented as least square means with 95% confidence intervals and a p-value of <0.05 was considered significant. RESULTS: The overall (N = 19) mean reference vessel diameter for QVA was 2.98 ± 1.24 mm vs. 3.47 ± 0.72 mm for IVUS (mean difference was -0.50 mm, (95% CI: -0.80, -0.20; p = 0.14). As expected, in the proximal segments (N = 12), the mean reference vessel diameters were larger: for QVA, it was 3.17 ± 1.34 mm vs. 3.55 ± 0.76 mm in IVUS, (mean difference was -0.38 mm, (95% CI: -0.79, 0.03; p = 0.40); while in the distal segments (N = 7), mean reference vessel diameters were smaller: for QVA, it was 2.64 ± 1.06 mm vs. 3.33 ± 0.67 mm in IVUS, (mean difference was -0.69 mm, (95% CI: -1.04, 0.34; p = 0.17). We observed a greater degree of acute gain in cases where the treatment balloon size correlated with the IVUS measured reference size. CONCLUSION: Angiography underestimates infrapopliteal reference vessel lumen size even when quantitatively assessed. Adjunctive IVUS imaging use in guiding BTK procedures could help ensure adequate sizing and possibly impact immediate post-procedure indices.

1-year outcomes with the Absorb bioresorbable scaffold in patients with coronary artery disease: a patient-level, pooled meta-analysis.

BACKGROUND: Compared with metallic drug-eluting stents, bioresorbable vascular scaffolds (BVS) offer the potential to improve long-term outcomes of percutaneous coronary intervention. Whether or not these devices are as safe and effective as drug-eluting stents within the first year after implantation is unknown. METHODS: We did a patient-level, pooled meta-analysis of four randomised trials in which 3389 patients with stable coronary artery disease or a stabilised acute coronary syndrome were enrolled at 301 academic and medical centres in North America, Europe, and the Asia-Pacific region. These patients were randomly assigned to the everolimus-eluting Absorb BVS (n=2164) or the Xience cobalt-chromium everolimus-eluting stent (CoCr-EES; n=1225). The primary endpoints were the 1-year relative rates of the patient-oriented composite endpoint (all-cause mortality, all myocardial infarction, or all revascularisation) and the device-oriented composite endpoint of target lesion failure (cardiac mortality, target vessel-related myocardial infarction, or ischaemia-driven target lesion revascularisation). All analyses were by intention to treat. The four randomised trials included in our meta-analysis are all registered with ClinicalTrials.gov, numbers NCT01751906, NCT01844284, NCT01923740, and NCT01425281. FINDINGS: The summary treatment effect for the 1-year relative rates of the patient-oriented composite endpoint did not differ significantly different between BVS and CoCr-EES (relative risk [RR] 1·09 [0·89-1·34], p=0·38). Similarly, the 1-year relative rates of the device-oriented composite endpoint did not differ between the groups (RR 1·22 [95% CI 0·91-1·64], p=0·17). Target vessel-related myocardial infarction was increased with BVS compared with CoCr-EES (RR 1·45 [95% CI 1·02-2·07], p=0·04), due in part to non-significant increases in peri-procedural myocardial infarction and device thrombosis with BVS (RR 2·09 [0·92-4·75], p=0·08). The relative rates of all-cause and cardiac mortality, all myocardial infarction, ischaemia-driven target lesion revascularisation, and all revascularisation did not differ between BVS and CoCr-EES. Results were similar after multivariable adjustment for baseline imbalances, and were consistent across most subgroups and in sensitivity analysis when two additional randomised trials with less than 1 year of follow-up were included. INTERPRETATION: In this meta-analysis, BVS did not lead to different rates of composite patient-oriented and device-oriented adverse events at 1-year follow-up compared with CoCr-EES. FUNDING: Abbott Vascular.

Evaluation of a fully bioresorbable vascular scaffold in patients with coronary artery disease: design of and rationale for the ABSORB III randomized trial.

BACKGROUND: Randomized trials have demonstrated progressive improvements in clinical and angiographic measures of restenosis with technologic iterations from balloon angioplasty to bare-metal stents and subsequently to drug-eluting stents (DES). However, the permanent presence of a metal stent prevents coronary vasomotion, autoregulation, and adaptive coronary remodeling. The limitations imposed by a permanent metal implant may be overcome with a bioresorbable scaffold. ABSORB III is a large-scale, multicenter, randomized trial designed to support US premarket approval of the ABSORB BVS platform and is the first study with sufficient size to allow valid examination of the relative clinical outcomes between metallic DES and bioresorbable scaffold. DESIGN: ABSORB III (ClincalTrials.gov NCT01751906) will register approximately 2,262 patients and includes a lead-in phase (n = 50), the primary randomized analysis group (n = 2,000), an imaging cohort (n = 200), and a pharmacokinetic substudy (n = 12). In the primary analysis group, approximately 2,000 patients with up to 2 de novo native coronary artery lesions in separate epicardial vessels will be prospectively assigned in a 2:1 ratio to ABSORB BVS versus XIENCE everolimus-eluting stents (EES). The primary end point is target lesion failure (the composite of cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization) at 1 year, powered for noninferiority of ABSORB BVS compared to XIENCE EES. Clinical follow-up will continue for 5 years. Enrollment has been completed, and the principal results will be available in the fall of 2015. CONCLUSIONS: The large-scale ABSORB III randomized trial will evaluate the safety and effectiveness of ABSORB BVS compared to XIENCE EES in the treatment of patients with coronary artery disease.

Stent Thrombosis and Dual Antiplatelet Therapy Interruption With Everolimus-Eluting Stents: Insights From the Xience V Coronary Stent System Trials.

BACKGROUND: Whether premature dual antiplatelet therapy (DAPT) interruption is safe in patients receiving cobalt chromium everolimus-eluting stents remains controversial. We sought to examine the relationship between DAPT discontinuation and stent thrombosis (ST) after cobalt chromium everolimus-eluting stents. METHODS AND RESULTS: Outcomes from 11,219 patients were pooled from 3 randomized trials and 4 registries with 2-year follow-up period after cobalt chromium everolimus-eluting stent implantation. Rates of definite/probable ST were analyzed according to DAPT discontinuation in the following time intervals: 0 to 30, 30 to 90, 90 to 180, 180 to 365, and 365 to 730 days. Eighty-five cases of ST (0.75%) occurred in 83 patients during 2 years, with 41 (48.2%) events occurring within 30 days. The 2-year ST rate in patients interrupting DAPT at any time was similar to that in patients never interrupting DAPT through 2 years (25/4067 [0.63%] versus 58/7152 [0.83%] respectively; P=0.27]. By propensity and DAPT usage-adjusted multivariable analysis, permanent DAPT discontinuation before 30 days was independently associated with the occurrence of ST (hazard ratio [95% confidence interval], 26.8 [8.4-85.4]; P<0.0001), whereas permanent DAPT discontinuation in any interval after 90 days was not associated with ST. Only 2 ST events occurred after DAPT discontinuation between 30 and 90 days (both between 30 and 60 days), and the association between permanent DAPT discontinuation and ST during this period is unclear (hazard ratio [95% confidence interval], 8.7 [2.0-37.3]; P=0.004 for adjusted analysis and 3.4 [0.8-13.8]; P=0.07 for the unadjusted analysis). CONCLUSIONS: In this large pooled experience, permanent DAPT discontinuation before 30 days after cobalt chromium everolimus-eluting stent implantation was strongly associated with ST, whereas DAPT discontinuation beyond 90 days appeared safe. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180310, NCT00180479, NCT00307047, NCT00402272, NCT00496938, NCT00676520, and NCT00631228.