Feasibility and safety of non-invasive ultrasound therapy (NIUT) on an porcine aortic valve.

Calcific aortic stenosis (CAS) is associated with advanced age and comorbidities, therefore a non-invasive therapy for it would be beneficial. We previously demonstrated that ultrasound therapy improved calcified bioprosthetic valve function in an open chest model. For translational applications, we tested non-invasive ultrasound therapy (NIUT) transthoracically on swine aortic valves and investigated the need for antithrombotic treatment as a follow-up. Primary objective: feasibility and safety of NIUT. Secondary objectives: occurrence, severity and evolution of side effects during therapy and at 1 month follow-up. The device (Valvosoft, Cardiawave) consisted of an electronically steered multi-element transducer and a 2D echocardiographic probe. Three groups of swine received treatment on aortic valves: NIUT (group 1; n = 10); NIUT and 1 month antithrombotic treatment (group 2; n = 5); sham group (group 3; n = 4). Feasibility was successfully reached in all treated swine (n = 15) and no life-threatening arrhythmia were detected. Non-sustained ventricular tachycardia occurred during the procedure in seven swine. Decrease or interruption of NIUT ended arrhythmia. Histopathology revealed no valve or surrounding tissue damage and echocardiography revealed no valvular dysfunction. Only one animal had side effects [right ventricle (RV) dilatation], but the RV normalized after therapy cessation with no sequelae at follow-up. No disturbance in biological markers nor valve thrombosis were observed at follow-up. Antithrombotic treatment did not demonstrate any advantage. Survival at 30 d was 100%. We demonstrated, in vivo, the feasibility and safety of transthoracic NIUT on aortic valves in a swine model without serious adverse events. We expect this first-time transthoracic delivery of NIUT to pave the way towards a new non-invasive approach to valve softening in human CAS to restore valve function.

One-Year Clinical Outcomes of Patients Presenting With ST-Segment Elevation Myocardial Infarction Caused by Bifurcation Culprit Lesions Treated With the Stentys Self-Apposing Coronary Stent: Results From the APPOSITION III Study.

OBJECTIVE: To investigate outcomes in patients with ST-segment elevation myocardial infarction (STEMI) after treatment with the Stentys self-apposing stent (Stentys SAS; Stentys S.A.) for bifurcation culprit lesions. BACKGROUND: The nitinol, self-expanding Stentys was initially developed as a dedicated bifurcation stent. The stent facilitates a provisional strategy by accommodating its diameter to both the proximal and distal reference diameters and offering an opportunity to "disconnect" the interconnectors, opening the stent toward the side branch. METHODS: The APPOSITION (a post-market registry to assess the Stentys self-expanding coronary stent in acute myocardial infarction) III study was a prospective, multicenter, international, observational study including STEMI patients undergoing primary percutaneous coronary intervention (PCI) with the Stentys SAS. Clinical endpoints were evaluated and stratified by bifurcation vs non-bifurcation culprit lesions. RESULTS: From 965 patients included, a total of 123 (13%) were documented as having a bifurcation lesion. Target-vessel revascularization (TVR) rates were higher in the bifurcation subgroup (16.4% vs 10.0%; P=.04). Although not statistically significant, other endpoints were numerically higher in the bifurcation subgroup: major adverse cardiac events (MACE; 12.7% vs 8.8%), myocardial infarction (MI; 3.4% vs 1.8%), and definite/probable stent thrombosis (ST; 5.8% vs 3.1%). However, when postdilation was performed, clinical endpoints were similar between bifurcation and non-bifurcation lesions: MACE (8.7% vs 8.4%), MI (1.2% vs 0.7%), and definite/probable ST (3.7% vs 2.4%). CONCLUSIONS: The use of the Stentys SAS was safe and feasible for the treatment of bifurcation lesions in the setting of primary PCI for STEMI treatment with acceptable 1-year cardiovascular event rates, which improved when postdilation was performed.

Clinical outcomes with the STENTYS self-apposing coronary stent in patients presenting with ST-segment elevation myocardial infarction: two-year insights from the APPOSITION III (A Post-Market registry to assess the STENTYS self-exPanding COronary Stent In AcuTe MyocardIal InfarctiON) registry.

AIMS: The APPOSITION III registry evaluated the feasibility and performance of the STENTYS self-apposing stent in an ST-segment elevation myocardial infarction (STEMI) population. This novel self-apposing stent device lowers stent strut malapposition rates and therefore carries the potential to prevent stent undersizing during primary percutaneous coronary intervention (PCI) in STEMI patients. To date, no long-term data are available using this device in the setting of STEMI. We aimed to evaluate the long-term clinical outcomes of the APPOSITION III registry. METHODS AND RESULTS: This was an international, prospective, multicentre post-marketing registry. The study population consisted of 965 STEMI patients. The primary endpoint, major adverse cardiac events (MACE), was defined as the composite of cardiac death, recurrent target vessel myocardial infarction (TV-MI), and clinically driven target lesion revascularisation (CD-TLR). At two years, MACE occurred in 11.2%, cardiac death occurred in 2.3%, TV-MI occurred in 2.3% and CD-TLR in 9.2% of patients. The two-year definite stent thrombosis (ST) rate was 3.3%. Incremental event rates between one- and two-year follow-up were 1.0% for TV-MI, 1.8% for CD-TLR, and 0.5% for definite ST. Post-dilation resulted in significantly reduced CD-TLR and ST rates at 30-day landmark analyses. Results were equivalent between the BMS and PES STENTYS subgroups. CONCLUSIONS: This registry revealed low rates of adverse events at two-year follow-up, with an incremental ST rate as low as 0.5% in the second year, demonstrating that the self-apposing technique is feasible in STEMI patients on long-term follow-up while using post-dilatation.

STENTYS Self-Apposing sirolimus-eluting stent in ST-segment elevation myocardial infarction: results from the randomised APPOSITION IV trial.

AIMS: We sought to investigate the impact of the self-apposing, sirolimus-eluting STENTYS stent on midterm and long-term stent apposition and strut coverage compared with a zotarolimus-eluting balloon-expandable stent in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI). METHODS AND RESULTS: In the APPOSITION IV trial, 152 STEMI patients were randomised (3:2) to the self-apposing, sirolimus-eluting STENTYS stent or a commercially available zotarolimus-eluting balloon-expandable stent at 12 sites in five countries with angiographic follow-up and optical coherence tomography at four or nine months. At four months, a lower percentage of malapposed stent struts was observed in the STENTYS group (N=21; Nstruts=501) compared with controls (N=26; Nstruts=326; 0.07% vs. 1.16%; p=0.002) with significantly more covered struts, using a 20 µm cut-off (94.32% vs. 89.09%; p=0.003). At nine months, the primary endpoint (percentage malapposed stent struts) was similar in both groups (STENTYS, N=40; Nstruts=566; control, N=21; Nstruts=292), showing complete apposition (p=0.55) and near total (>96%) coverage (p=0.58). CONCLUSIONS: In STEMI patients undergoing PPCI, the self-apposing, sirolimus-eluting STENTYS stent was equivalent to a conventional drug-eluting balloon-expandable stent with respect to late stent strut apposition and coverage at nine months. However, stent strut apposition and coverage at four months were significantly better in the STENTYS group.

First-in-man evaluation of the novel balloon delivery system STENTYS Xposition S for the self-apposing coronary artery stent: impact on longitudinal geographic miss during stenting.

AIMS: A novel balloon delivery system (BDS) for the self-apposing STENTYS sirolimus-eluting stent (SES) has been developed for highly precise longitudinal stent positioning and deployment. The aim of this first-in-man study is to report the quantitative coronary analysis (QCA) angiography and optical coherence tomography (OCT) results as well as the 30-day clinical outcomes of the STENTYS Xposition S SES. METHODS AND RESULTS: We included 25 patients (mean age 66.1±10.7 years) with stable coronary artery disease (24%) or acute coronary syndrome (including STEMI in 40%). The device was successfully placed at the intended site in all cases (100%), without procedural complications. Longitudinal geographic miss (entire lesion length [on QCA] not completely covered by the stent) was not observed. Pre-procedural MLD on QCA was 1.30±0.74 mm and post-procedural MLD was 2.74±0.44 mm, p<0.001 (acute gain 1.44±0.70 mm). OCT analyses showed a low percentage of malapposed stent struts directly post stent placement (2.4%), which further decreased after post-dilatation (0.6%, p=0.013), while mean stent area increased (from 9.7 mm2 to 10.5 mm2, p<0.001). At 30-day clinical follow-up, one (4%) major adverse cardiac event (MACE) was observed. One acute stent thrombosis (ST) occurred immediately post procedure in a STEMI patient which was related to inadequate medication therapy. CONCLUSIONS: This first-in-man study demonstrated that the use of the novel STENTYS Xposition S balloon delivery system is feasible with a high technical success rate without longitudinal geographical miss. Stent strut malapposition rate directly after STENTYS placement was low and improved further after post-dilatation.

Incidence and potential mechanism of resolved, persistent and newly acquired malapposition three days after implantation of self-expanding or balloon-expandable stents in a STEMI population: insights from optical coherence tomography in the APPOSITION II study.

AIMS: The aim of the current study was to investigate the frequency and mechanisms of sequential incomplete stent apposition (ISA) changes such as persistent, resolved or newly acquired ISA during the first three days after primary PCI (pPCI) in a matched segment-level analysis, with the comparison between self-expanding and balloon-expandable stents assessed by optical coherence tomography (OCT). METHODS AND RESULTS: The current analysis is a substudy of the APPOSITION II study that included 69 patients (self-expanding: 35, balloon-expandable: 34) using serial optical coherence tomography (OCT) post procedure and three days after pPCI. In order to evaluate a temporal change in ISA, stented regions were segmented using fiduciary landmarks. In a total of 228 corresponding segments, persistent and newly acquired ISA were less frequently observed in self-expanding stents than in balloon-expandable stents (11.5% vs. 33.9%, p<0.01, 2.7% vs. 14.8%, p<0.01, respectively). New appearances of ISA were caused by tissue resorption, vasorelaxation and "early" recoil in balloon-expandable stents, and only tissue resorption in self-expanding stents. CONCLUSIONS: Three days after pPCI, tissue resorption and vasorelaxation were biological factors associated with new appearance of ISA while "early" recoil of balloon-expandable stents was a mechanical factor. Both persistent ISA and newly acquired ISA occurred less frequently in self-expanding stents, resulting in a low number of ISA segments compared to balloon-expandable stents. Clinical Trials Registration Information: Randomised Comparison Between the STENTYS Self-expanding Coronary Stent and a Balloon-expandable Stent in Acute Myocardial Infarction (APPOSITION II). ClinicalTrials.gov Identifier: NCT01008085

One-year clinical outcomes of the STENTYS Self-Apposing¨ coronary stent in patients presenting with ST-segment elevation myocardial infarction: results from the APPOSITION III registry.

AIMS: The aim of APPOSITION III was to evaluate the feasibility and performance of the STENTYS Self-Apposing¨ stent (STENTYS S.A., Paris, France) in the setting of primary percutaneous coronary intervention (PCI). METHODS AND RESULTS: APPOSITION III was an international, prospective, multicentre registry. The study population consisted of 965 patients. The rate of the primary endpoint major adverse cardiac events (MACE), defined as the composite of cardiac death, recurrent target vessel myocardial infarction (TV-MI), and clinically driven target lesion revascularisation (CD-TLR), at one year was 9.3%. One-year cardiac death rate was 2.0%, TV-MI rate was 1.3%, CD-TLR rate was 7.4% and definite/probable stent thrombosis (ST) rate was 3.5% (definite ST 2.8%). An interim safety analysis of in-hospital outcomes in the first 400 patients showed higher event rates if post-dilation was not performed, and post-dilations became highly recommended in the remaining cohort. Patients undergoing post-dilation eventually showed a numerically lower one-year MACE rate (8.4% vs. 11.3%, p=0.137). One-year TV-MI (0.8% vs. 2.5%, p=0.027) and definite ST (1.9% vs. 5.0%, p=0.010) rates were significantly lower if post-dilation was performed, with the divergence occurring at <30 days. CONCLUSIONS: The use of the STENTYS Self-Apposing¨ stent in the setting of primary PCI was feasible and associated with acceptable cardiovascular event rates which improved when post-dilation was performed.

APPOSITION V: STENTYS coronary stent system clinical trial in subjects with ST-segment elevation myocardial infarction--rationale and design.

BACKGROUND: Primary percutaneous coronary intervention (PCI) has considerably improved clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) when compared with thrombolytic therapy. Prognosis after primary PCI might be further improved by decreasing stent-related complications such as stent thrombosis. The STENTYS self-apposing stent has been shown to be superior compared with balloon-expandable stents with regard to stent apposition. The current prospective randomized trial was designed to evaluate whether the superior stent apposition of the STENTYS stent results in clinical outcomes that are at least noninferior to a conventional balloon-expandable stent. METHODS: The APPOSITION V is a prospective, multicenter, international, single-blinded, randomized controlled trial in STEMI patients. Randomization will be performed in a 2:1 ratio between the self-apposing nitinol bare-metal STENTYS stent and the balloon-expandable bare-metal MULTI-LINK. The primary end point is defined as target vessel failure, which is a composite of cardiac death, target vessel-related recurrent myocardial infarction, or clinically driven target vessel revascularization, at 1-year follow-up. Baseline intravascular ultrasound and optical coherence tomography (OCT) substudies will be performed in 212 and 60 subjects, respectively, and a repeat angiography at 12 to 13 months will be performed in 105 subjects, including intravascular ultrasound and OCT (in the 60 OCT patients). This study is registered on ClinicalTrials.gov with number NCT01732341. CONCLUSION: APPOSITION V will be the first randomized trial powered on clinical end points that directly compares the STENTYS self-apposing stent with a conventional balloon-expandable stent in patients presenting with STEMI undergoing primary PCI.

Self-expanding versus balloon-expandable stents in acute myocardial infarction: results from the APPOSITION II study: self-expanding stents in ST-segment elevation myocardial infarction.

OBJECTIVES: This study sought to investigate whether self-expanding stents are more effective than balloon-expandable stents for reducing stent malapposition at 3 days after implantation in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. BACKGROUND: Acute myocardial infarction is associated with vasoconstriction and large thrombus burden. Resolution of vasoconstriction and thrombus load during the first hours to days after primary percutaneous coronary intervention may lead to stent undersizing and malapposition, which may subsequently lead to stent thrombosis or restenosis. In addition, aggressive stent deployment may cause distal embolization. METHODS: Eighty patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention were randomized to receive a self-expanding stent (STENTYS, STENTYS SA, Paris, France) (n = 43) or a balloon-expandable stent (VISION, Abbott Vascular, Santa Clara, California; or Driver, Medtronic, Minneapolis, Minnesota) (n = 37) at 9 European centers. The primary endpoint was the proportion of stent strut malapposition at 3 days after implantation measured by optical coherence tomography. Secondary endpoints included major adverse cardiac events (cardiac death, recurrent myocardial infarction, emergent bypass surgery, or clinically driven target lesion revascularization). RESULTS: At 3 days after implantation, on a per-strut basis, a lower rate of malapposed stent struts was observed by optical coherence tomography in the self-expanding stent group than in the balloon-expandable group (0.58% vs. 5.46%, p < 0.001). On a per-patient basis, none of the patients in the self-expanding stent group versus 28% in the balloon-expandable group presented ≥5% malapposed struts (p < 0.001). At 6 months, major adverse cardiac events were 2.3% versus 0% in the self-expanding and balloon-expandable groups, respectively (p = NS). CONCLUSIONS: Strut malapposition at 3 days is significantly lower in ST-segment elevation myocardial infarction patients allocated to self-expanding stents when than in those allocated to balloon-expandable stents. The impact of this difference on clinical outcome and the risk of late stent thrombosis need to be evaluated further. (Randomized Comparison Between the STENTYS Self-expanding Coronary Stent and a Balloon-expandable Stent in Acute Myocardial Infarction [APPOSITION II]; NCT01008085).

Six-month clinical and angiographic results of the STENTYS® self-apposing stent in bifurcation lesions.

AIMS: We report the clinical and angiographic results of the OPEN I study, a multicentre prospective single-arm study evaluating both the drug-eluting and bare metal STENTYS® stents in the treatment of coronary bifurcation lesions. METHODS AND RESULTS: The STENTYS® stent is a provisional, self-expanding, nitinol stent with small interconnections that can be disconnected by balloon angioplasty in between the stent struts to provide access to the side branch (SB) and full ostium coverage. In nine European centres, 60 stents (33 BMS, 27 DES) were implanted in 63 patients (procedural success of 95.2%). Angiographic QCA and IVUS were used to measure acute gain and late loss. The Medina classification showed 35 patients (58%) had disease affecting the SB (true bifurcations) and 19 patients (32%) had disease in all three arms. The average bifurcation angulation pre-stenting was 60°±21°. Post-stenting, disconnection was performed on 90% of the stents implanted. In 18 cases, disconnection was followed by SB stenting with all SB stents successfully implanted. Post-stenting, the bifurcation angle was 51°. The primary clinical endpoint, cumulative MACE at six months, was low for DES (3.7%) but higher for BMS (27.3%) with the latter driven exclusively by clinically-driven TLR rates (3.7% vs. 24.2%). No cardiac deaths were recorded at six months and one patient had a non-Q wave infarct. The secondary angiographic endpoint of late luminal loss (LLL) was measured for both DES (paclitaxel) and BMS stents in the proximal main branch (MB), MB, distal MB as well as the SB. The values for DES were 0.39 mm, 0.42 mm, 0.40 mm and 0.16 mm, respectively. The values for BMS were 0.86 mm, 0.87 mm, 0.85 mm and 0.54 mm, respectively. Observed results using matched IVUS analysis at six months revealed an increase in mean stent area (mm²) for DES from 7.52±1.86 at baseline to 12.32±2.90 at six month follow-up (p <0.001); and for BMS from 7.95±1.40 to 11.56±2.22 (p <0.001), with no decrease in minimum lumen area (MLA) for DES (5.10 to 4.91) and a minimal decrease for BMS (5.74 to 5.15). CONCLUSIONS: This first-in-man (FIM) study on the STENTYS® stent showed excellent procedural success and a relatively low MACE with competitively low LLL in both MB and SB at six months for the DES version and LLL comparable to other BMS for the BMS version. The disconnectable struts offered excellent "cross over" to T- stenting when necessary and the increased gains in stent area over time.

Assessment of the safety and performance of the STENTYS self-expanding coronary stent in acute myocardial infarction: results from the APPOSITION I study.

AIMS: In the setting of ST-elevation myocardial infarction (STEMI), epicardial vasoconstriction and thrombus load may lead to stent undersizing and malapposition after primary percutaneous coronary intervention (PPCI), which can both be responsible for stent thrombosis or restenosis. Aggressive stent deployment can, on the other hand, cause distal embolisation and the no-reflow phenomenon. The purpose of our study was to evaluate the safety and feasibility of a novel self-expanding stent by assessing the clinical, angiographic and intravascular outcomes after stent deployment at three days and at six months follow-up. METHODS AND RESULTS: This prospective, multicentre, non-randomised study enrolled 25 STEMI patients undergoing PPCI; a nitinol, self-expanding, coronary stent (STENTYS® stent; STENTYS, Paris, France) was used in all patients. Angiography and intravascular ultrasound (IVUS) or optical coherence tomography (OCT) were performed immediately after stent deployment, after three days and at six months. Primary safety endpoints were mortality, reinfarction, stent thrombosis and stroke at discharge and at six months. The primary feasibility endpoints were technical, device and procedural success, and stent apposition at three days and six months. Secondary endpoints included distal embolisation, binary restenosis, ischaemia-driven target lesion revascularisation (TLR) and late lumen loss (LLL). There were no adverse events at discharge or at six months. Technical, device and procedural success were 100%, 96% and 96%, respectively. IVUS showed a significant vasodilatation distal to the culprit lesion at three-day follow-up (+19%), with a concordant expansion of the implanted stent (+18%), p≤0.001 for both values. One case of distal embolisation was reported. There were no cases of late stent malapposition at six months. In-stent and in-segment LLL were 0.71±0.71 mm and 0.58±0.61 mm. Binary restenosis was 25%, ischaemia-driven TLR was 12%. CONCLUSIONS: This study shows that the use of the STENTYS® self-expanding stent is safe and feasible in STEMI patients. Three days after the procedure, the stent expanded to the same extent as the epicardial vasodilatation and appeared completely apposed to the vessel wall. This could be of benefit in preventing stent thrombosis in the setting of STEMI.