Clinical Outcomes Before and After Complete Everolimus-Eluting Bioresorbable Scaffold Resorption: Five-Year Follow-Up From the ABSORB III Trial.

BACKGROUND: The Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support similar to those of metallic drug-eluting stents, followed by complete resorption in ≈3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization) at 1 year with BVS compared with cobalt chromium everolimus-eluting stents. Between 1 and 3 years and cumulative to 3 years, adverse event rates (particularly target vessel myocardial infarction and scaffold thrombosis) were increased after BVS. We sought to assess clinical outcomes after BVS through 5 years, including beyond the 3-year time point of complete scaffold resorption. METHODS: Clinical outcomes from ABSORB III were analyzed by randomized device (intention to treat) cumulative to 5 years and between 3 and 5 years. RESULTS: Rates of target lesion failure, target vessel myocardial infarction, and scaffold thrombosis were increased through the 5-year follow-up with BVS compared with everolimus-eluting stents. However, between 3 and 5 years, reductions in the relative hazards of the BVS compared with everolimus-eluting stents were observed, particularly for target lesion failure (hazard ratio, 0.83 [95% CI, 0.55-1.24] versus 1.35 [95% CI, 1.02-1.78]; Pint=0.052) and scaffold thrombosis (hazard ratio, 0.26 [95% CI, 0.02-2.87] versus 3.23 [95% CI, 1.25-8.30]; Pint=0.056) compared with the 0- to 3-year time period. CONCLUSIONS: In the ABSORB III trial, cumulative 5-year adverse event rates were increased after BVS compared with everolimus-eluting stents. However, the period of excess risk for BVS ended at 3 years, coincident with complete scaffold resorption. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT01751906.

IN.PACT SFA Clinical Study Using the IN.PACT Admiral Drug-Coated Balloon in a Chinese Patient Population.

Purpose: To confirm the safety and effectiveness of the IN.PACT Admiral drug-coated balloon (DCB) as a treatment for de novo and native artery restenotic lesions in the superficial femoral artery (SFA) and/or proximal popliteal artery in Chinese subjects. Materials and Methods: IN.PACT SFA China (ClinicalTrials.gov identifier NCT02118532) was a single-arm, independently adjudicated, prospective, premarket study that enrolled 143 subjects (mean age 66.8±7.7 years; 107 men) at 15 centers. The predominant risk factors were hypertension (104, 72.7%) and diabetes mellitus (66, 46.2%). The majority of subjects were classified as Rutherford category 2 or 3 [69 (48.3%) and 55 (38.5%), respectively]; 19 (13.3%) subjects had critical limb ischemia (Rutherford category 4). The mean lesion length was 10.4±6.51 cm; more than half of the lesions (75, 52.4%) were chronic total occlusions. Calcification was found in 66 (46.2%) lesions. Outcomes at 12 months were compared with DCB safety and effectiveness performance goals derived from the literature. The 30-day primary safety outcome was a composite of freedom from device- and procedure-related mortality, major target limb amputation, and clinically-driven target lesion revascularization (CD-TLR). Results: The primary safety outcome was 99.3% at 30 days. Follow-up compliance at 12 months was 92.6%. Estimated 1-year primary patency using Kaplan-Meier analysis was 90.9% and freedom from CD-TLR was 97.1%. The rate of CD-TLR at 12 months was 2.9%. The Rutherford category status improved significantly (p<0.001) between baseline and 12 months. Conclusion: Results from IN.PACT SFA China demonstrated high rates of patency and low rates of CD-TLR in Chinese subjects through 12 months despite patient and lesion complexity. These data are consistent with the results of other IN.PACT DCB trials.

SUPERB final 3-year outcomes using interwoven nitinol biomimetic supera stent.

IMPORTANCE: Long-term outcomes of an interwoven nitinol stent design represent the best in class for treatment of lower limb arterial obstructive disease METHODS: The subjects were enrolled in an open single arm study comparing the outcomes to an FDA mandated objective performance goal (OPG). RESULTS: About 325 patients (264 intention-to-treat and 64 roll-in subjects) were enrolled. Mean follow-up period was 887+/- 352 days. Treated lesion lengths were 7.8 cm ± 4.3 cm in the trial with chronic total occlusions comprising 24.6% (65/264) of subjects. Freedom from clinically driven target lesion revascularization (CD-TLR) at 12 months was 89%, at 24 and 36 months it was 84% and 82% respectively. The difference in the 12 month CD-TLR was 7% at 36 months. The difference of clinically driven-TLR at 36 months in those subjects who received their stents deployed nominally in length, compressed or elongated (between -10% and +10% nominal length) had an impact on the CD-TLR. At 2 and 3 years, freedom from CD-TLR in minimal compression was 86.7%, and was 90.0% for moderate compression. In those stents deployed with minimal, moderate, or severe elongation (10-20%, 20-40%, or >40%, respectively) freedom from CD-TLR of 84.1%, 87.4%, and 77.0% respectively at 12 months. At 2 and 3 years, freedom from CD-TLR for moderate elongation was 81.8% and 78.2%, and for severe elongation was 63.4% and 42.3%, respectively. Fractures were distinctly uncommon with this stent with a single facture event in the 36 month follow-up period. DISCUSSION: The interwoven nitinol design stent is a stent that achieves an excellent primary patency but further maintains the durability of the stent through 36 months. Optimal stent deployment remains critical to the performance of this stent device and requires optimal vessel preparation. © 2017 Wiley Periodicals, Inc.

Impact of Implantation Technique and Plaque Morphology on Strut Embedment and Scaffold Expansion of Polylactide Bioresorbable Scaffold　- Insights From ABSORB Japan Trial.

BACKGROUND: The optimal implantation technique for the bioresorbable scaffold (Absorb, Abbott Vascular) is still a matter of debate. The purpose of the present study was to evaluate the effect of implantation technique on strut embedment and scaffold expansion.Methods and Results:Strut embedment depth and scaffold expansion index assessed by optical coherence tomography (OCT) (minimum scaffold area/reference vessel area) were evaluated in the ABSORB Japan trial (OCT subgroup: 87 lesions) with respect to implantation technique using either quantitative coronary angiography (QCA) or OCT. Strut embedment was assessed at the strut level (n=667), while scaffold expansion was assessed at the lesion level (n=81). The mean embedment depth was 63±59 µm. Balloon sizing and inflation pressure had no direct effect on strut embedment. Plaque morphology affected strut embedment [nonatherosclerotic (58.9±54.3 µm), fibroatheroma (73.3±59.6 µm), fibrous plaque (59.7±51.1 µm), and fibrocalcific plaque (-3.1±61.6 µm, negative value means malapposition), P <0.001]. The balloon-artery ratio positively correlated with the expansion index. This relationship was stronger when the OCT-derived reference vessel diameter (RVD) was used as a reference for balloon selection rather than the QCA-derived one [predilatation (Pearson correlation r: QCA: 0.167 vs. OCT: 0.552), postdilatation (QCA: 0.316 vs. OCT: 0.717)]. CONCLUSIONS: Underlying plaque morphology influenced strut embedment, whereas implantation technique had no direct effect on it. Optimal balloon sizing based on OCT-derived RVD might be recommended. However, the safety of such a strategy should be investigated in a prospective trial. (Circ J 2016; 80: 2317-2326).

Nitinol stent implantation in the superficial femoral artery and proximal popliteal artery: twelve-month results from the complete SE multicenter trial.

PURPOSE: To determine the safety and efficacy of a new-generation nitinol stent with enhanced flexibility in arterial lesions in the superficial femoral artery (SFA) and proximal popliteal artery (PPA). METHODS: The Complete Self-Expanding (SE) Multicenter Trial (ClinicalTrials.gov identifier NCT00814970) enrolled 196 patients (124 men; mean age 68.7±10.5 years) from 28 centers in the United States and Europe. The patients presented with intermittent claudication (193/196) or ischemic rest pain (3/196) and were treated with nitinol stents for obstructive lesions of the SFA or PPA. Over a quarter of lesions (29.9%) were chronic total occlusions. The mean lesion length was 60.7 mm. Moderate to severe calcification was present in 91.0% of lesions. RESULTS: A total of 225 stents were successfully implanted in 213 (99.5%) of 214 lesions. Acute lesion success (<30% residual stenosis) was achieved in 90.0%. There were no in-hospital major adverse events. Primary patency (defined as a peak systolic velocity ratio <2.0) at 12 months was 72.6%. Clinically-driven target lesion revascularization (TLR) was required in 8.4% of patients at 12 months. The mean ankle-brachial index increased from 0.7 at baseline to 0.9, and there was sustained improvement in the Rutherford category, with 83% of patients classified as Rutherford category 0 or 1 at 12-month follow-up. No stent fractures were detected through 12 months. CONCLUSION: In this multicenter trial, primary implantation of a new-generation self-expanding nitinol stent in the SFA and PPA was associated with a low rate of TLR and sustained clinical benefit at 12 months without stent fracture.

Randomized Comparison Between Everolimus-Eluting Bioresorbable Scaffold and Metallic Stent: Multimodality Imaging Through 3 Years.

OBJECTIVES: The aim of this study was to investigate the vascular responses and fates of the scaffold after bioresorbable vascular scaffold (BVS) implantation using multimodality imaging. BACKGROUND: Serial comprehensive image assessments after BVS implantation in the context of a randomized trial have not yet been reported. METHODS: In the ABSORB Japan trial, 400 patients were randomized to a BVS (n = 266) or a cobalt-chromium everolimus-eluting stent (n = 134). Through 3 years, patients underwent serial angiography and intravascular ultrasound or optical coherence tomography (OCT). RESULTS: Luminal dimension at 3 years was consistently smaller with the BVS than with the cobalt-chromium everolimus-eluting stent (mean angiographic minimal luminal diameter 2.04 ± 0.63 mm vs. 2.40 ± 0.56 mm, mean difference -0.37 mm [95% confidence interval: -0.50 to -0.24 mm]; p < 0.001), mainly because of smaller device area (6.13 ± 2.03 mm2 vs. 7.15 ± 2.16 mm2, mean difference -1.04 mm2 [95% confidence interval: -1.66 to -0.42 mm2]; p < 0.001), and larger neointimal area (2.10 ± 0.61 mm2 vs. 1.86 ± 0.64 mm2, mean difference 0.24 mm2 [95% confidence interval: 0.06 to 0.43 mm2]; p = 0.01) by OCT. BVS-treated vessels did not show previously reported favorable vessel responses, such as positive vessel remodeling, late luminal enlargement, and restoration of vasomotion, although the OCT-based healing score was on average zero (interquartile range: 0.00 to 0.00). At 3 years, intraluminal scaffold dismantling (ISD) was observed in 14% of BVS. On serial OCT, ISD was observed in 6 lesions at 2 years, where the struts had been fully apposed at post-procedure, while ISD was observed in 12 lesions at 3 years, where 8 lesions were free from ISD on 2-year OCT. In 5 cases of very late scaffold thrombosis, strut discontinuities were detected in all 4 cases with available OCT immediately before reintervention. CONCLUSIONS: In this multimodality serial imaging study, luminal dimension at 3 years was smaller with the BVS than with the cobalt-chromium everolimus-eluting stent. ISD, suspected to be one of the mechanisms of very late BVS thrombosis, was observed in a substantial proportion of cases at 3 years, which developed between post-procedure and 2 years and even beyond 2 years. (AVJ-301 Clinical Trial: A Clinical Evaluation of AVJ-301 [Absorb™ BVS] in Japanese Population [ABSORB JAPAN]; NCT01844284).

A polymer-based, paclitaxel-eluting stent in patients with coronary artery disease.

BACKGROUND: Restenosis after coronary stenting necessitates repeated percutaneous or surgical revascularization procedures. The delivery of paclitaxel to the site of vascular injury may reduce the incidence of neointimal hyperplasia and restenosis. METHODS: At 73 U.S. centers, we enrolled 1314 patients who were receiving a stent in a single, previously untreated coronary-artery stenosis (vessel diameter, 2.5 to 3.75 mm; lesion length, 10 to 28 mm) in a prospective, randomized, double-blind study. A total of 652 patients were randomly assigned to receive a bare-metal stent, and 662 to receive an identical-appearing, slow-release, polymer-based, paclitaxel-eluting stent. Angiographic follow-up was prespecified at nine months in 732 patients. RESULTS: In terms of base-line characteristics, the two groups were well matched. Diabetes mellitus was present in 24.2 percent of patients; the mean reference-vessel diameter was 2.75 mm, and the mean lesion length was 13.4 mm. A mean of 1.08 stents (length, 21.8 mm) were implanted per patient. The rate of ischemia-driven target-vessel revascularization at nine months was reduced from 12.0 percent with the implantation of a bare-metal stent to 4.7 percent with the implantation of a paclitaxel-eluting stent (relative risk, 0.39; 95 percent confidence interval, 0.26 to 0.59; P<0.001). Target-lesion revascularization was required in 3.0 percent of the group that received a paclitaxel-eluting stent, as compared with 11.3 percent of the group that received a bare-metal stent (relative risk, 0.27; 95 percent confidence interval, 0.16 to 0.43; P<0.001). The rate of angiographic restenosis was reduced from 26.6 percent to 7.9 percent with the paclitaxel-eluting stent (relative risk, 0.30; 95 percent confidence interval, 0.19 to 0.46; P<0.001). The nine-month composite rates of death from cardiac causes or myocardial infarction (4.7 percent and 4.3 percent, respectively) and stent thrombosis (0.6 percent and 0.8 percent, respectively) were similar in the group that received a paclitaxel-eluting stent and the group that received a bare-metal stent. CONCLUSIONS: As compared with bare-metal stents, the slow-release, polymer-based, paclitaxel-eluting stent is safe and markedly reduces the rates of clinical and angiographic restenosis at nine months.

Detailed intravascular ultrasound analysis of Zotarolimus-eluting phosphorylcholine-coated cobalt-chromium alloy stent in de novo coronary lesions (results from the ENDEAVOR II trial).

Zotarolimus-eluting phosphorylcholine-coated cobalt-chromium alloy Driver stents (ZES) demonstrated significant reductions in target lesion revascularization rate with few apparent adverse events compared with bare metal stents (BMS; uncoated Driver stents) in a prospective, multicenter, double-blind, randomized controlled trial in de novo coronary lesions. The aim of this study was to examine detailed vascular responses to ZES compared with BMS using serial intravascular ultrasound analysis. A total of 343 patients (ZES n = 178, BMS n = 165) were enrolled in this formal, prespecified intravascular ultrasound substudy of the Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE Zotarolimus-Eluting Driver Coronary Stent in de Novo Native Coronary Artery Lesions (ENDEAVOR II), a prospective, multicenter, double-blind, randomized controlled trial to compare ZES and BMS in de novo native coronary artery lesions. Quantitative and qualitative intravascular ultrasound analyses were performed postprocedurally and at 8-month follow-up in stented and reference segments. ZES showed significantly less neointima, with a larger lumen than BMS at 8 months (percentage neointimal volume 17.6 +/- 10.1% vs 29.4 +/- 17.2%, p <0.0001; maximum percentage neointimal area 32.9 +/- 13.0% vs 47.6 +/- 18.6%, p <0.0001; minimum luminal area 4.9 +/- 1.6 vs 4.0 +/- 1.7 mm(2), p <0.0001) and no unfavorable edge effect. In the 18-mm single stents, ZES showed evenly inhibited neointima compared with BMS. Neither persistent stent-edge dissection nor late-acquired incomplete stent apposition was observed in either group. In conclusion, ZES showed evenly inhibited neointima with no apparent adverse vascular response in stented and reference segments at 8 months compared with BMS.

9-Month Clinical and Angiographic Outcomes of the COBRA Polyzene-F NanoCoated Coronary Stent System.

OBJECTIVES: The aim of this study was to assess the safety and effectiveness of the COBRA Polyzene-F NanoCoated Coronary Stent System (CeloNova Biosciences, San Antonio, Texas) for the treatment of de novo coronary artery lesions. BACKGROUND: Polyzene-F-coated coronary stents have shown reduced thrombogenicity and inflammation in preclinical studies. METHODS: Patients with de novo coronary artery lesions meeting eligibility criteria were enrolled in a nonrandomized, prospective clinical trial. The primary endpoint was target vessel failure (TVF) (defined as a composite of cardiac death, myocardial infarction, or clinically driven target vessel revascularization) at 9 months. A pre-specified subset was planned for routine repeat angiographic follow-up at 9 months. The powered secondary endpoint was mean late lumen loss (LL). The comparator was a performance goal derived from meta-analysis of historical bare-metal stent trials of 19.62% for TVF and 1.1 mm for LL. Other secondary endpoints were clinically driven target lesion revascularization and definite or probable stent thrombosis. RESULTS: Of 296 enrolled patients, 287 (97%) completed primary endpoint analysis; 130 were planned for angiographic follow-up and 115 (88%) completed. At 9 months, TVF had occurred in 33 patients (11.5%; upper 95% confidence boundary: 15.07%), including 1 (0.3%) cardiac death, 20 (7.0%) myocardial infarctions (17 periprocedural), and 17 (5.9%) target vessel revascularizations. LL was 0.84 ± 0.48 mm (upper 95% confidence boundary: 0.92). Target lesion revascularization occurred in 13 patients (4.6%). There were no stent thrombosis events. CONCLUSIONS: The COBRA Polyzene-F stent met performance goals for TVF and LL at 9 months. There was an excellent safety profile, with infrequent late myocardial infarction and no stent thrombosis.

3-Year Clinical Outcomes With Everolimus-Eluting Bioresorbable Coronary Scaffolds: The ABSORB III Trial.

BACKGROUND: The Absorb everolimus-eluting poly-L-lactic acid-based bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete bioresorption in approximately 3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction [TVMI], or ischemia-driven target lesion revascularization) at 1 year in 2,008 patients with coronary artery disease randomized to BVS versus cobalt-chromium everolimus-eluting stents (EES). OBJECTIVES: This study sought to assess clinical outcomes through 3 years following BVS implantation. METHODS: Clinical outcomes from the ABSORB III trial were analyzed by randomized treatment assignment cumulative through 3 years, and between 1 and 3 years. RESULTS: The primary composite endpoint of target lesion failure through 3 years occurred in 13.4% of BVS patients and 10.4% of EES patients (p = 0.06), and between 1 and 3 years in 7.0% versus 6.0% of patients, respectively (p = 0.39). TVMI through 3 years was increased with BVS (8.6% vs. 5.9%; p = 0.03), as was device thrombosis (2.3% vs. 0.7%; p = 0.01). In BVS-assigned patients, treatment of very small vessels (those with quantitatively determined reference vessel diameter <2.25 mm) was an independent predictor of 3-year TLF and scaffold thrombosis. CONCLUSIONS: In the ABSORB III trial, 3-year adverse event rates were higher with BVS than EES, particularly TVMI and device thrombosis. Longer-term clinical follow-up is required to determine whether bioresorption of the polymeric scaffold will influence patient prognosis. (ABSORB III Randomized Controlled Trial [RCT] [ABSORB-III]; NCT01751906).

Clinical efficacy of polymer-based paclitaxel-eluting stents in the treatment of complex, long coronary artery lesions from a multicenter, randomized trial: support for the use of drug-eluting stents in contemporary clinical practice.

BACKGROUND: Intracoronary polymer-based stent delivery of paclitaxel has been shown to be effective in reducing restenosis in simple coronary lesions, but the evidence base for contemporary use in longer, more complex coronary stenoses is lacking. METHODS AND RESULTS: TAXUS VI is a prospective, multicenter, double-blind, randomized trial assessing clinical and angiographic outcomes of the TAXUS Moderate Release paclitaxel-eluting stent in the treatment of long, complex coronary artery lesions. Four hundred forty-eight patients at 44 sites were randomized (1:1) between a drug-eluting TAXUS Express2 and an uncoated Express2 control stent. Per protocol, the 9-month follow-up included an angiographic reevaluation in all patients. The primary end point was the rate of target-vessel revascularization 9 months after the study procedure; secondary end points included the rate of target-lesion revascularization and binary restenosis at follow-up. Mean lesion length in the study was 20.6 mm, with a mean stent-covered length of 33.4 mm. Of all lesions, 55.6% were classified as complex lesions (type C of the AHA/ACC classification). At 9 months, target-vessel revascularization was 9.1% in the TAXUS group and 19.4% in the control group (P=0.0027; relative reduction, 53%). Target-lesion revascularization was reduced from 18.9% to 6.8%, respectively (P=0.0001). The incidence of major adverse cardiac events was similar in the 2 groups, 16.4% and 22.5% in TAXUS and control, respectively (P=0.12), including comparable rates for acute myocardial infarction. Binary restenosis in the stented area was reduced from 32.9% in the control group to 9.1% in the TAXUS patients (P<0.0001). CONCLUSIONS: The finding that the TAXUS Moderate Release stent system is safe and effective in the treatment of long, complex coronary artery lesions provides the evidence base for the more widespread use of drug-eluting stents in contemporary clinical practice.

The fate of patients with clinical recurrence after sirolimus-eluting stent implantation (a two-year follow-up analysis from the SIRIUS trial).

Although clinical outcomes after sirolimus-eluting stents (SESs) have been previously described ("primary" success rates), the fate of patients whose SES implantation fail and who require ischemia-driven target lesion revascularization is poorly understood. The SIRIUS trial is a prospective, randomized, clinical trial that includes 533 evaluable patients with SESs. Twenty-two of these patients had adjudicated ischemia-driven target lesion revascularization (4.1%) within the first year of follow-up and comprised the study population of this analysis. Of these patients, 11 (50%) had diabetes, and restenotic lesions were focal and located at the proximal stent edge in 91% and 73% of patients, respectively. Restenosis was treated with bare metal stent implantation, balloon dilatation, or intravascular brachytherapy in 82%, 13.5%, and 4.5% of patients, respectively. At 1-year follow-up after the first recurrence (2-year follow-up after the index procedure), only 5 of these patients (23%) required a second repeat revascularization procedure. Risk factors for a second recurrence after treatment of SES restenosis were female gender, long lesions that required long stents at the index procedure, and an early first recurrence. In conclusion, SES failure treated with traditional percutaneous coronary intervention yielded good outcome at 1-year follow-up (secondary failure rate only 23%), perhaps due to the focal nature of the SES restenotic lesion. Future studies should evaluate other methods, including drug-eluting stents, to further optimize the outcome of treatment of SES failures.

Bioresorbable Everolimus-Eluting Vascular Scaffold for Patients With Peripheral Artery Disease (ESPRIT I): 2-Year Clinical and Imaging Results.

OBJECTIVES: This is the first-in-human study of a drug-eluting bioresorbable vascular scaffold (BVS) for treatment of peripheral artery disease (PAD) involving the external iliac artery (EIA) and superficial femoral artery (SFA). BACKGROUND: Drug-eluting BVS has shown promise in coronary arteries. METHODS: The ESPRIT BVS system is a device-drug combination consisting of an everolimus-eluting poly-l-lactide scaffold. Safety and performance were evaluated in 35 subjects with symptomatic claudication. RESULTS: Lesions were located in the SFA (88.6%) and EIA (11.4%). Mean lesion length was 35.7 ± 16.0 mm. The study device was successfully deployed in 100% of cases, without recoil. Procedure-related minor complications were observed in 3 patients (groin hematoma, dissection). Within 2 years there was 1 unrelated death, but no patients in this cohort had an amputation. At 1 and 2 years, the binary restenosis rates were 12.1% and 16.1%, respectively, and target lesion revascularization was performed in 3 of 34 patients (8.8%) and 4 of 32 patients (11.8%), respectively. The ankle brachial index 0.75 ± 0.14 improved from pre-procedure to 0.96 ± 0.16 at 2 years' follow-up. At 2 years, 71.0% of the patients were Rutherford-Becker 0, and 93.5% achieved a maximum walking distance of 1,500 feet. CONCLUSIONS: The safety of the ESPRIT BVS was demonstrated with no procedure or device-related deaths or amputations within 2 years. The low occurrence of revascularizations was consistent with duplex-ultrasonography showing sustained patency at 2-years. (A Clinical Evaluation of the Abbott Vascular ESPRIT BVS [Bioresorbable Vascular Scaffold] System [ESPRIT I]; NCT01468974).

Is quantitative coronary angiography reliable in assessing the lumen gain after treatment with the everolimus-eluting bioresorbable polylactide scaffold?

AIMS: The current study aimed to assess the difference in lumen dimension measurements between optical coherence tomography (OCT) and quantitative coronary angiography (QCA) in the polymeric bioresorbable scaffold and metallic stent. METHODS AND RESULTS: In the randomised ABSORB Japan trial, 87 lesions in the Absorb arm and 44 lesions in the XIENCE arm were analysed. Post-procedural OCT-QCA lumen dimensions were assessed in matched proximal/distal non-stented/non-scaffolded reference (n=199), scaffolded (n=145) and stented (n=75) cross-sections at the two device edges using the Bland-Altman method. In the non-stented/non-scaffolded reference segments, QCA systematically underestimated lumen diameter (LD) compared with OCT (accuracy, -0.26 mm; precision, 0.47 mm; 95% limits of agreement as a mean bias±1.96 standard deviation, -1.18-0.66 mm). When compared to OCT, QCA of the Absorb led to a more severe underestimation of the LD (-0.30 mm; 0.39 mm; -1.06-0.46 mm) than with the XIENCE (-0.14 mm; 0.31 mm; -0.75-0.46 mm). QCA underestimated LD by 9.1%, 4.9%, and 9.8% in the reference, stented, and scaffolded segments, respectively. The protrusion distance of struts was larger in the Absorb arm than in the XIENCE arm (135±27 µm vs. 18±26 µm, p<0.001), and may have contributed to the observed differences. CONCLUSIONS: In-device QCA measurement was differently affected by the presence of a metallic or polymeric scaffold, a fact that had a significant impact on the QCA assessment of acute gain and post-procedural minimum LD.

One-year clinical results with the slow-release, polymer-based, paclitaxel-eluting TAXUS stent: the TAXUS-IV trial.

BACKGROUND: The safety and efficacy of the slow-release, polymer-based, paclitaxel-eluting stent after implantation in a broad cross section of de novo coronary lesions at 1 year are unknown. METHODS AND RESULTS: In the TAXUS-IV trial, 1314 patients with single de novo coronary lesions 10 to 28 mm in length, with reference-vessel diameter 2.5 to 3.75 mm, coverable by a single study stent, were prospectively randomized to the slow-release, polymer-based, paclitaxel-eluting TAXUS stent or an identical-appearing bare-metal EXPRESS stent. By actuarial analysis, the TAXUS stent compared with the bare-metal stent reduced the 12-month rates of target-lesion revascularization by 73% (4.4% versus 15.1%, P<0.0001), target-vessel revascularization by 62% (7.1% versus 17.1%, P<0.0001), target-vessel failure by 52% (10.0% versus 19.4%, P<0.0001), and composite major adverse cardiac events by 49% (10.8% versus 20.0%, P<0.0001). The 1-year rates of cardiac death (1.4% versus 1.3%), myocardial infarction (3.5% versus 4.7%), and subacute thrombosis (0.6% versus 0.8%) were similar between the paclitaxel-eluting and control stents, respectively. Between 9 and 12 months, there were significantly fewer myocardial infarctions (0% versus 1.1%, P=0.007), target-vessel revascularizations (2.4% versus 5.8%, P=0.002), and major adverse cardiac events (2.4% versus 6.3%, P=0.0009) in the paclitaxel-eluting stent than in the control stent group, respectively. CONCLUSIONS: The relative efficacy reported at 9 months for the polymer-based, paclitaxel-eluting TAXUS stent compared with the EXPRESS stent is preserved and continues to increase at 1 year, with no safety concerns apparent.

Evaluation of the Medtronic (Driver) cobalt-chromium alloy coronary stent system.

The Driver Registry was a prospective, multicenter, nonrandomized study to evaluate the clinical safety and efficacy of the Driver cobalt-chromium alloy stent. Use of the cobalt-chromium alloy in place of stainless steel offers enhanced visibility and radial strength with thinner structural elements. The registry enrolled 298 patients with symptomatic ischemic heart disease attributable to de novo or restenotic nonstented native lesions of a single vessel amenable to percutaneous stenting. The primary composite end point was the incidence of major adverse cardiac events (death, myocardial infarction, emergency bypass surgery, or target lesion revascularization) 180 days after enrollment. Quantitative coronary angiography was performed before and after the index stent deployment and repeated at 6 months in 83 patients. Mean patient age was 62.6 years, mean reference vessel diameter was 3.07 mm before the procedure, and mean lesion length was 11.04 mm. Fifty-one patients received multiple stents. Angiographic success rate was 100% and procedural success rate was 98.3%. Cumulative incidence of major adverse cardiac events was 5.7% and target lesion revascularization was 3.4% at 180 days. In-stent late loss was 0.94 mm at 180 days, and no subacute stent thromboses were observed. This registry demonstrated the safety and efficacy of this novel coronary stent platform.

Impact of asymmetric stent expansion on neointimal hyperplasia following sirolimus-eluting stent implantation.

To assess whether asymmetric stent expansion affects suppression of neointimal hyperplasia after sirolimus-eluting stent implantation, 64 patients in the SIRolImUS-coated Bx Velocity stent trial who underwent single 18-mm stent implantation and 3-dimensional intravascular ultrasonography at 8-month follow-up were enrolled. To assess the longitudinal stent asymmetric expansion, 2 cross sections with a maximal/minimal stent area were chosen in each patient. To assess for tomographic stent asymmetric expansion, stent eccentricity was determined by dividing the minimum stent diameter by the maximum stent diameter. At the 2 cross sections with a maximal/minimal stent area, a sirolimus-eluting stent reduced neointimal hyperplasia significantly with no interaction between the treatment and stent areas. A sirolimus-eluting stent also significantly reduced neointimal hyperplasia in the concentric and eccentric stent groups.

Impact of coronary culprit lesion calcium in patients undergoing paclitaxel-eluting stent implantation (a TAXUS-IV sub study).

Randomized clinical trials have shown that paclitaxel-eluting stents significantly reduce restenosis after percutaneous coronary intervention. The impact of lesion calcification on the efficacy of paclitaxel-eluting stents is unknown. In the TAXUS-IV trial, 1,314 patients who underwent percutaneous coronary intervention were randomly assigned to a bare-metal or paclitaxel-eluting stent. By core laboratory analysis, 247 lesions (19%) were moderately or severely calcified. At the 9-month angiographic follow-up examination, the paclitaxel-eluting stent had significantly reduced the amount of late loss compared with the control stent (0.26 +/- 0.56 vs 0.51 +/- 0.48 mm, p = 0.015) within the analysis segment in the calcific lesions. The analysis segment restenosis rate was similar in patients with calcified and noncalcified lesions after paclitaxel-eluting stent implantation (7.5% vs 8.0%, respectively; p = 1.0). The rate of ischemia-driven target lesion revascularization (TLR) at 1 year was reduced by 56% in patients with calcified lesions (11.9% vs 5.1%, p = 0.09) and by 75% in noncalcified lesions (15.7% vs 4.3%, p <0.0001). By interaction testing, the efficacy of the paclitaxel-eluting stent in reducing TLR at 1 year was similar in the calcified and noncalcified lesions (p = 0.30). Moreover, by multivariate analysis, implantation of the paclitaxel-eluting stent was a powerful independent predictor of freedom from TLR, with similar hazard ratios for efficacy in calcified and noncalcified lesions (0.30 and 0.26, respectively). In conclusion, implantation of paclitaxel-eluting stents in patients with de novo coronary lesions significantly reduced restenosis in patients with and without calcified lesions.

Predictors of edge stenosis following sirolimus-eluting stent deployment (a quantitative intravascular ultrasound analysis from the SIRIUS trial).

To study the interaction of the sirolimus-eluting stent and vessel margins, we analyzed the intravascular ultrasound parameters in 317 edges of 167 stents having 18 edge stenoses at 8 months of follow-up from the SIRIUS trial. Of the baseline parameters, a larger reference percentage of plaque area and a larger edge stent area/reference minimum lumen area were associated with edge stenosis in the sirolimus-eluting stent cohort compared with the incidence of edge stenosis in the bare metal stent cohort. Thus, full lesion coverage and matching the stented segment properly to the adjacent segment using intravascular ultrasound guidance may improve sirolimus-eluting stent implantation efficacy further.

Comparison of a polymer-based paclitaxel-eluting stent with a bare metal stent in patients with complex coronary artery disease: a randomized controlled trial.

CONTEXT: Compared with bare metal stents, drug-eluting stents reduce restenosis in noncomplex lesions. The utility of drug-eluting stents has not been evaluated in more difficult stenoses. OBJECTIVE: To investigate the safety and efficacy of the polymer-based, slow-release paclitaxel-eluting stent in a patient population with more complex lesions than previously studied. DESIGN, SETTING, AND PATIENTS: Prospective, placebo-controlled, double-blind, multicenter randomized trial conducted from February 2003 to March 2004 at 66 academic and community-based institutions with 1156 patients who underwent stent implantation in a single coronary artery stenosis (vessel diameter, 2.25-4.0 mm; lesion length, 10-46 mm), including 664 patients (57.4%) with complex or previously unstudied lesions (requiring 2.25-mm, 4.0-mm, and/or multiple stents) and 9-month clinical and angiographic follow-up. INTERVENTIONS: Patients were randomly assigned to receive 1 or more bare metal stents (n = 579) or identical-appearing paclitaxel-eluting stents (n = 577). MAIN OUTCOME MEASURE: Ischemia-driven target vessel revascularization at 9 months. RESULTS: Baseline characteristics were well matched. Diabetes was present in 31% of patients. The mean (SD) reference vessel diameter was 2.69 (0.57) mm, the reference lesion length was 17.2 (9.2) mm, and 78% of lesions were type B2/C. A mean (SD) of 1.38 (0.58) stents (total mean [SD] length, 28.4 [13.1] mm) were implanted per lesion; 33% of lesions required multiple stents. Stents that were 2.25 mm and 4.0 mm in diameter were used in 18% and 17% of lesions, respectively. Compared with bare metal stents, paclitaxel-eluting stents reduced the 9-month rate of target lesion revascularization from 15.7% to 8.6% (P<.001) and target vessel revascularization from 17.3% to 12.1% (P = .02). Similar rates were observed for cardiac death or myocardial infarction (5.5% for bare metal stent group vs 5.7% for paclitaxel-eluting stent group) and stent thrombosis (0.7% in both groups). Angiographic restenosis was reduced from 33.9% to 18.9% in the entire study cohort (P<.001), including among patients receiving 2.25-mm stents (49.4% vs 31.2%; P = .01), 4.0-mm stents (14.4% vs 3.5%; P = .02), and multiple stents (57.8% vs 27.2%; P<.001). CONCLUSION: Compared with a bare metal stent, implantation of the paclitaxel-eluting stent in a patient population with complex lesions effectively reduces clinical and angiographic restenosis.