Drug-Coated Balloons: Hope or Hot Air: Update on the Role of Coronary DCB.

PURPOSE OF REVIEW: The present manuscript reviews the mechanism of action of drug-coated balloons (DCBs), offering a brief summary of the main clinical evidence on these devices. RECENT FINDINGS: DCBs are regular semi-compliant balloons coated with antiproliferative agents that are rapidly released on contact with the vessel intima, exerting an anti-restenotic effect. This technology may offer some benefits of drug-eluting stents, in particular for the treatment of restenotic lesions, small vessels, and in patients at high-bleeding risk, when the prolonged dual antiplatelet regimen should be avoided. Most recent data have pointed to a possible benefit of these devices in treating bare metal stents (BMS) or drug-eluting stents in-stent restenosis (DES ISR), effectively reducing the recurrence of restenosis and avoiding additional layers of metal in the same coronary segment. In other clinical scenarios such as bifurcations, small vessels, and de novo lesions, data is more scarce and the benefits are still unclear. There are potential benefits related to the use of DCB in selected populations. However, larger clinical trials with longer follow-up are still needed to confirm the enthusiastic initial results.

Bioresorbable Scaffolds for Coronary Stenosis: When and How Based Upon Current Studies.

PURPOSE OF REVIEW: First-generation bioresorbable scaffolds (BRS), largely represented by the poly-l-lactic acid (PLLA) ABSORB (Abbott Vascular, Temecula, Illinois, US), have demonstrated, in low to moderate lesion complexity, similar efficacy to current generation metallic drug-eluting stents. However, a trend toward more device thrombosis has been observed, especially when the scaffolds are used in off-label situations. In this review, we address the most relevant drawbacks of these devices and, based on the available scientific data, we visit the scenarios where there is more uncertainty about their indication, trying to identify the lesions/patients to whom this technology should be voided at its current stage of development. RECENT FINDINGS: Based on available data from randomized trials and observational real world registries, the use of first generation BRS has been associated with a trend to higher acute/subacute thrombosis rate, which might be partially explained by the peculiarities related to their deployment technique, such as the need for precise vessel sizing and caution on post-dilation. Special attention should be paid when using these devices to treat small coronary arteries (<2.5 mm), long lesions requiring overlapping, and patients with acute coronary syndrome, in particular those with ST-segment elevation myocardial infarction (STEMI). Finally, the role of these devices is still uncertain in more complex lesion anatomies such as bifurcations, ostial lesions, etc. Although based on attractive clinical premises, the current indications of BRS are still limited by significant drawbacks observed in the first generation of these devices. Of note, new generation scaffolds are currently in preclinical and clinical evaluation and present features that might surpass most of these limitations.

The unmet needs: How future technologies will address current limitations of bioresorbable scaffold technology.

First-generation bioresorbable scaffolds (BRS), represented by the three marked-approved devices (Absorb BVS 1.1, DESolve NX, and DREAMS) have demonstrated, in low to moderate angiographic scenarios, similar efficacy to current generation metallic drug-eluting stents. However, a trend toward more device thrombosis have been observed, especially when the scaffolds are used in off-label situations. Among the main shortcomings of this novel technology, we highlight: (1) Increased strut thickness (≥150 µm) and crossing profile; (2) low resistance to overexpansion; (3) lack of radiopacity, and; (4) special storage requirements. In order to overcome these limitations and improve their acute performance and midterm safety, a dozen of novel BRS are currently under research, in different stages of development. In the present review, we address three of these new technologies, pointing out their innovative features and initial clinical results. © 2016 Wiley Periodicals, Inc.

Thrombus aspiration in ST-segment elevation myocardial infarction.

Primary percutaneous coronary intervention (PCI) has become the treatment of choice in patients with ST-segment elevation myocardial infarction (STEMI) throughout the last years. A significant number of studies have demonstrated a morbidity and mortality benefit over thrombolysis, which has been attributed to better coronary perfusion in patients undergoing primary PCI. Even though it usually achieves normal flow in the affected epicardial vessel, myocardial reperfusion is not fully restored in a significant percentage of patients. This is commonly the result of distal thrombus embolization with subsequent impairment of myocardial microcirculation. Recognition of this has led to the development of a number of devices with different mechanisms, including thrombus aspiration catheters, in order to reduce distal embolization and therefore improve myocardial perfusion. Recent studies indeed demonstrate that the use of such devices offer additional clinical advantage in patients undergoing primary PCI in comparison to the standard PCI, whether in other trials it could not be proved. This paper focuses on general mechanisms of thrombus formation and discusses favorable and unfavorable studies towards thrombus aspiration in STEMI and its main aspects and it comes up with specific subjects that could benefit or not from the procedure of thrombus aspiration.

The ABSORB EXTEND study: preliminary report of the twelve-month clinical outcomes in the first 512 patients enrolled.

AIMS: The safety and performance of the Absorb Bioresorbable Vascular Scaffold (Absorb BVS) system (Abbott Vascular, Santa Clara, CA, USA) has been previously established in 131 patients from cohort A and cohort B of the first-in-man ABSORB trial. Following this trial, ABSORB EXTEND was initiated as a global continued access study (outside of the USA) to expand experience with the Absorb BVS system to different geographies with broader inclusion criteria to include the treatment of longer lesions and multiple vessels. We report in this manuscript the twelve-month clinical outcomes of the first 512 patients in this population. METHODS AND RESULTS: ABSORB EXTEND is a prospective, single-arm, open-label clinical study which will enrol up to 800 patients at up to 100 sites. Included are patients with lesions ≤28 mm in length and reference vessel diameter of 2.0-3.8 mm (as assessed by on-line QCA or IVUS). Treatment of a maximum of two de novo native coronary artery lesions is permitted when each lesion is located in a different epicardial vessel. An independent clinical events committee adjudicates all endpoint-related events. At one year, for the first 512 patients enrolled in the study, the composite endpoints of ischaemia-driven MACE and ischaemia-driven target vessel failure were 4.3% and 4.9%, respectively. The cumulative rate of ARC defined definite and probable scaffold thrombosis for this population was 0.8% at one year. CONCLUSIONS: This interim analysis of the ABSORB EXTEND study shows low rates of MACE and scaffold thrombosis. The study is registered on clinicaltrials.gov (unique identifier NCT01023789).

First-in-man assessment of the InSeal VCD, a novel closure device for large puncture accesses.

AIMS: To demonstrate the feasibility and efficacy of the novel InSeal VCD for the closure of large puncture holes following percutaneous structural interventions. METHODS AND RESULTS: Prospective, non-randomised, single-arm, single-centre study with a series of patients submitted to endovascular treatment of abdominal and thoracic aortic aneurysm as well as transcatheter aortic valve implantation in whom the InSeal VCD was used to close the access site. These patients were followed up for one year with clinical examination, ankle-brachial index and Doppler ultrasound. The primary endpoint was the occurrence of major vascular complications at the puncture site. From a total of nine patients screened, seven were selected to receive the InSeal VCD. Technical and therapeutic successes were achieved in all cases. The sheath profiles used in these procedures ranged from 18 Fr to 25 Fr. No major vascular complications were observed during the follow-up period. Average ankle-brachial index pre-intervention and at one-month follow-up were 0.85 and 0.82, respectively. CONCLUSIONS: The InSeal VCD was shown to be effective in achieving acute and chronic haemostasis after usage of higher profile endovascular devices in this study. These results translated into no clinical complications up to one-year clinical follow-up.

Relação Balão/Artéria e Volume de Obstrução Neontimal Após Implante de Stent Eluidor de Zotarolimus / Balloon/Artery Ratio and Neointimal Hyperplasia Volume Obstruction After Zotarolimus-Eluting Stent Implantation

Introdução: O volume de hiperplasia intimal correlaciona-se com a injúria arterial após implante de stents não farmacológicos. No entanto, pouco se sabe a respeito do impacto da injúria arterial na resposta inflamatória/proliferativa com os stents farmacológicos. Investigamos o impacto da injúria arterial, avaliada pela relação balão/artéria, no volume de obstrução neontimal, avaliado pelo ultrassom intracoronário 12 meses após o implante de stents farmacológicos com eluição de zotarolimus. Métodos: A relação balão/artéria foi definida como a razão do diâmetro máximo do balão, obtido no implante ou na pós-dilatação, e o diâmetro de referência do vaso pré-procedimento. Os pacientes foram categorizados em dois grupos: relação balão/artéria alta (≥ 1,15) e relação balão/artéria baixa (< 1,15). Resultados: Foram incluídos 86 pacientes, nos grupos relação balão/artéria baixa (n = 47/48 lesões) ou relação balão/artéria alta (n = 39/48 lesões). As características clínicas, angiográficas e do procedimento não diferiram entre os grupos, à exceção do diâmetro de referência dos vasos (2,73 ± 0,45 mm vs. 2,97 ± 0,40 mm; p = 0,01). Aos 12 meses, observou-se semelhante perda tardia intra-stent (0,59 ± 0,32 mm vs. 0,62 ± ...

Background: Intimal hyperplasia volume is correlated to arterial injury after bare-metal stenting. However, little is known about the impact of arterial injury on the inflammatory/ proliferative response with drug-eluting stents. We investigated the impact of arterial injury, evaluated by the balloon/artery ratio, on neointimal hyperplasia volume obstruction, evaluated by intravascular ultrasound, 12 months after zotarolimus-eluting stent implantation. Methods: Balloon/ artery ratio was defined as the ratio of the maximum balloon diameter, using the maximal implantation or post-dilatation pressure, and the reference diameter of the vessel obtained before the procedure. Patients were divided into two groups: high balloon/artery ratio (≥ 1.15) and low balloon/artery ratio (< 1.15). Results: A total of 86 patients were included in the low balloon/artery ratio group (n = 47/48 lesions) or high balloon/artery ratio (n = 39/48 lesions). The clinical, angiographic and procedurerelated characteristics were not different between groups, except for the vessel reference diameter (2.73 ± 0.45 mm vs. 2.97 ± 0.40 mm; p = 0.01). At 12 months, similar in-stent late loss was observed (0.59 ± 0.32 mm vs. 0.62 ± 0.42 mm; p = 0.92), as well as binary restenosis (4.2% in both cohorts; p > 0.99). Instent neointimal hyperplasia volume obstruction (15.2 ± 14.3% vs. 12.5 ± 10.1%; p = 0.62) showed no difference between groups. No correlation was observed between balloon/artery ratio ...

Serial greyscale and radiofrequency intravascular ultrasound assessment of plaque modification and vessel geometry at proximal and distal edges of bare metal and first-generation drug-eluting stents.

BACKGROUND: Little is known about the correlation between modifications in plaque composition at stent edges and the changes in vessel geometry. This study sought to evaluate, by serial greyscale intravascular ultrasound (IVUS) and Virtual Histology intravascular ultrasound (VH-IVUS), the modifications in plaque composition at the edges of drug-eluting and bare metal stents and the correlation of these findings with changes in the measurements of vessel, lumen and plaque area at those segments. METHODS AND RESULTS: Single-centre, prospective and randomised (1:1) evaluation of 40 patients with acute coronary syndrome treated with bare metal (Driver; Medtronic, Santa Clara, CA, USA; n=20 patients) or drug-eluting stents (Cypher; Cordis, Miami Lakes, FL, USA; n=20 patients). IVUS and VH-IVUS assessments were done post-procedure and at nine months. Primary endpoint included the modification in vessel, lumen and plaque area and in the composition of the plaque in the mean time between the baseline and follow-up procedure. At the proximal edge of the vessel treated with the Cypher stent, a trend toward positive vessel remodelling (D=+0.6 mm², p=0.06) was observed while at the distal edge, less plaque growth (D=+0.2 mm² vs. D=+1.1 mm², p<0.001), resulted in a larger lumen area at follow-up. By VH, there was a marked reduction in the percentage of fibrotic tissue and necrotic core at the edges of both stents and a positive correlation was seen between increase in percentage of fibro-fatty component and increase in plaque area (r=0.78, p=0.01). CONCLUSION: Patients treated with drug-eluting stents (DES) experienced less plaque growth, especially at the distal edge of the stents. Modifications in plaque composition, with increase in fibrofatty tissue component, may partially explain these findings.

Angiographic and intravascular ultrasound findings following implantation of the Endeavor zotarolimus-eluting stents in patients from the real-world clinical practice.

AIMS: The aim of this study was to investigate the angiographic and intravascular ultrasound (IVUS) findings of the Endeavor zotarolimus-eluting stent (ZES) in patients from a "real-world" clinical practice. METHODS AND RESULTS: From January to March 2006, 100 patients undergoing routine or emergency percutaneous intervention were prospectively enrolled at one institution. Overall, 39% of the patients were diabetics and 80.8% of lesions were type B2/C. A total of 140 lesions were successfully treated with 174 ZES, and procedural success was 98%. Mean vessel diameter was 2.69 mm and mean lesion length was 16.0 mm; at 6-month angiographic follow-up (completed in 96%), in-stent late lumen loss was 0.66 mm, and in-segment restenosis was 8.2%. Angiographic restenosis was increased among diabetics (15.5 vs. 2.6%, p=0.009), and diabetes was the only significant predictor of angiographic restenosis (OR=15.27 [95%CI 2.45-95.04], p=0.003). By IVUS (performed in 88% at 6-month), % volume obstruction was 14.4+/-13.4%, and there was no late acquired incomplete stent apposition (ISA). At 1-year, overall MACE rate was 6%, including 5 TLRs (4% of patients), with no occurrence of stent thrombosis. CONCLUSIONS: In this prospective "real-world" experience, the ZES demonstrated favourable angiographic and IVUS results in complex patients, with overall in-stent late lumen loss of 0.66 mm, and absence of late acquired ISA. At 1-year, there were no safety concerns including absence of death and stent thrombosis.