Nine-month results of the REFORM study: A prospective, single-arm, multicenter clinical study of the safety and effectiveness of the formula™ balloon-expandable stent for treatment of renal

Safety and Efficacy of Renal Denervation in Patients Taking Antihypertensive Medications

BACKGROUND

Renal denervation (RDN) reduces blood pressure (BP) in patients with uncontrolled hypertension in the absence of antihypertensive medications.

OBJECTIVES

This trial assessed the safety and efficacy of RDN in the presence of antihypertensive medications.

METHODS

SPYRAL HTN-ON MED is a prospective, randomized, sham-controlled, patient- and assessor-blinded trial enrolling patients from 56 clinical centers worldwide. Patients were prescribed 1 to 3 antihypertensive medications. Patients were randomized to radiofrequency RDN or sham control procedure. The primary efficacy endpoint was the baseline-adjusted change in mean 24-hour ambulatory systolic BP at 6 months between groups using a Bayesian trial design and analysis.

RESULTS

The treatment difference in the mean 24-hour ambulatory systolic BP from baseline to 6 months between the RDN group (n = 206; -6.5 ± 10.7 mm Hg) and sham control group (n = 131; -4.5 ± 10.3 mm Hg) was -1.9 mm Hg (95% CI: -4.4 to 0.5 mm Hg; P = 0.12). There was no significant difference between groups in the primary efficacy analysis with a posterior probability of superiority of 0.51 (Bayesian treatment difference: -0.03 mm Hg [95% CI: -2.82 to 2.77 mm Hg]). However, there were changes and increases in medication intensity among sham control patients. RDN was associated with a reduction in office systolic BP compared with sham control at 6 months (adjusted treatment difference: -4.9 mm Hg; P = 0.0015). Night-time BP reductions and win ratio analysis also favored RDN. There was 1 adverse safety event among 253 assessed patients.

CONCLUSIONS

There was no significant difference between groups in the primary analysis. However, multiple secondary endpoint analyses favored RDN over sham control. (SPYRAL HTN-ON MED Study [Global Clinical Study of Renal Denervation With the Symplicity Spyral Multi-electrode Renal Denervation System in Patients With Uncontrolled Hypertension in the Absence of Antihypertensive Medications]; NCT02439775).

Benefits of short-term or prolonged as compared to standard 1 year DAPT in patients with acute coronary syndrome treated with drug-eluting stents: a meta-analysis of 9 randomized trials

Optimal timepoint for the discontinuation of dual antiplatelet therapy (DAPT) after an acute coronary syndrome is still debated. In fact, despite a shortening of DAPT duration should be advocated, based on the negligible risk of thrombotic complications observed with newer generations of drug-eluting stents (DES), in order to reduce the hemorrhagic risk, a more prolonged anti-ischemic protection would be suitable for certain higher-risk patients, rendering the traditional 12 months strategy outdated. We performed an updated meta-analysis and indirect comparison of randomized trials comparing shorter vs extended DAPT duration in ACS patients undergoing percutaneous coronary interventions with DES. Literature and main scientific session abstracts were searched for studies comparing 3-6 (short-term) or prolonged (> 12 months) DAPT vs traditional 12 months in ACS patients treated with DES. The primary efficacy endpoint was mortality, primary safety endpoint was the occurrence of major bleedings. Secondary endpoints were myocardial infarction and stent thrombosis. We included three randomized clinical trials and six study sub-analysis comparing alternative (short-term or prolonged) DAPT vs 12 months in post-ACS, with a total of 15,738 patients. Mortality occurred in 1.8% of patients, with no difference according to DAPT duration (short-term vs standard DAPT: OR [95% CI] 1.00 [0.72-1.39], p = 0.99; > 12 vs 12 months: OR [95% CI] 0.87 [0.61-1.22], p = 0.41). No difference in the risk of recurrent myocardial infarction and stent thrombosis was observed between short-term and standard DAPT, while a significant reduction was achieved only when extending the duration beyond 12 months (MI: OR [95% CI] 0.49 [0.36-0.67], p < 0.00001; ST: OR [95% CI] 0.40 [0.23-0.70], p = 0.001). However, prolonged DAPT was associated with a significant increase in major bleedings (OR [95% CI] 1.69 [1.17-2.45], p = 0.006). In fact, indirect comparison confirmed a significant interaction between short-term vs prolonged DAPT and the risk of myocardial infarction (p < 0.001), stent thrombosis (p = 0.0006) and major bleeding complications (p = 0.02). Based on the current meta-analysis, among ACS patients treated with percutaneous coronary interventions with DES, a shorter-term (3 or 6 months) DAPT can be safely considered, offering a non-inferior protection from major cardiovascular ischemic events as compared to the standard 12 months strategy. Extending DAPT therapy beyond 12 months enhances the antithrombotic protection, although paying the fee of increasing major bleeding complications, therefore resulting in a null effect on mortality.

Validation of the diagnostic performance of 'HeartMedi V.1.0', a novel CT-derived fractional flow reserve measurement, for patients with coronary artery disease: a study protocol

INTRODUCTION

Coronary CT angiography (CCTA) is widely used for non-invasive coronary artery evaluation, but it is limited in identifying the nature of functional characteristics that cause ischaemia. Recent computational fluid dynamic (CFD) techniques applied to CCTA images permit non-invasive computation of fractional flow reserve (FFR), a measure of lesion-specific ischaemia. However, this technology has limitations, such as long computational time and the need for expensive equipment, which hinder widespread use.

METHODS AND ANALYSIS

This study is a prospective, multicentre, comparative and confirmatory trial designed to evaluate the diagnostic performance of HeartMedi V.1.0, a novel CT-derived FFR measurement for the detection of haemodynamically significant coronary artery stenoses identified by CCTA, based on invasive FFR as a reference standard. The invasive FFR values ≤0.80 will be considered haemodynamically significant. The study will enrol 184 patients who underwent CCTA, invasive coronary angiography and invasive FFR. Computational FFR (c-FFR) will be analysed by CFD techniques using a lumped parameter model based on vessel length method. Blinded core laboratory interpretation will be performed for CCTA, invasive coronary angiography, invasive FFR and c-FFR. The primary objective of the study is to compare the area under the receiver-operator characteristic curve between c-FFR and CCTA to non-invasively detect the presence of haemodynamically significant coronary stenosis. The secondary endpoints include diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value and correlation of c-FFR with invasive FFR.

ETHICS AND DISSEMINATION

The study has ethic approval from the ethics committee of Seoul National University Bundang Hospital (E-1709/420-001) and informed consent will be obtained for all enrolled patients. The result will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

KCT0002725; Pre-results.

Rationale and design of two randomized sham-controlled trials of catheter-based renal denervation in subjects with uncontrolled hypertension in the absence (SPYRAL HTN-OFF MED Pivotal) and presence (SPYRAL HTN-ON MED Expansion) of antihypertensive medications: a novel approach using Bayesian design

BACKGROUND

The SPYRAL HTN clinical trial program was initiated with two 80-patient pilot studies, SPYRAL HTN-OFF MED and SPYRAL HTN-ON MED, which provided biological proof of principle that renal denervation has a blood pressure-lowering effect versus sham controls for subjects with uncontrolled hypertension in the absence or presence of antihypertensive medications, respectively.

TRIAL DESIGN

Two multicenter, prospective, randomized, sham-controlled trials have been designed to evaluate the safety and efficacy of catheter-based renal denervation for the reduction of blood pressure in subjects with hypertension in the absence (SPYRAL HTN-OFF MED Pivotal) or presence (SPYRAL HTN-ON MED Expansion) of antihypertensive medications. The primary efficacy endpoint is baseline-adjusted change from baseline in 24-h ambulatory systolic blood pressure. The primary safety endpoint is incidence of major adverse events at 1 month after randomization (or 6 months in cases of new renal artery stenosis). Both trials utilize a Bayesian design to allow for prespecified interim analyses to take place, and thus, the final sample sizes are dependent on whether enrollment is stopped at the first or second interim analysis. SPYRAL HTN-OFF MED Pivotal will enroll up to 300 subjects and SPYRAL HTN-ON MED Expansion will enroll up to 221 subjects. A novel Bayesian power prior approach will leverage historical information from the pilot studies, with a degree of discounting determined by the level of agreement with data from the prospectively powered studies.

CONCLUSIONS

The Bayesian paradigm represents a novel and promising approach in device-based hypertension trials.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02439749 (SPYRAL HTN-OFF MED Pivotal) and NCT02439775 (SPYRAL HTN-ON MED Expansion).

First in man study of a new semi-open cell design Zephyr cobalt-chromium stent in large vessels and conduits

OBJECTIVES

We present a first-in-man clinical use of a new hybrid design stent in stenosed large vessels. Its unique C and S polylinks prevent foreshortening without compromising its strength. Its thin profile permits use of smaller introducer sheaths.

BACKGROUND

Stent angioplasty is widely employed in large vessel and conduit stenosis. These procedures are associated with difficulties due to large stent profiles, stent fractures, foreshortening and recoil. Cobalt chromium stents have high tensile strengths compared to stainless steel stents.

METHODS

A retrospective analysis of feasibility and safety of a new Cobalt chromium stent in large vessels namely aorta, pulmonary arteries and outflow conduits was done from two institutions. Demographic patient details, procedural results, complications and medium term follow-up were analyzed. Stent recoil, foreshortening, fractures were assessed.

RESULTS

Twenty patients including three with aortic coarctations, seven with stenosed conduits and 10 with pulmonary artery stenosis underwent stent angioplasty using 23 stents. Three stents were deployed to expand further a previously implanted stent. Procedure was successful in all patients, lumen increased by 150-300%, gradients reduced in all patients. There was no stent recoil, foreshortening or fractures. There were no complications. At a follow up of 3-27 months, there were no stent related complications and the gradients remained stable.

CONCLUSIONS

The new Zephyr stent was useful in a wide variety of stenotic lesions involving large vessels including those that were previously stented. Lack of stent recoil and foreshortening seems to be an advantage for this new stent that needs validation in larger multicenter studies.

Analysis of the risk factors for contrast-induced nephropathy in over-aged patients receiving coronary intervention

Contrast-induced nephropathy has been the common cause of hospital-acquired acute kidney injury in the elderly patients. This study aimed to analyze the risk factors for contrast-induced nephropathy in over-aged patients undergoing coronary angiography or percutaneous coronary intervention. A total of 470 over-aged patients (≥80 years old) were judged as the contrast-induced nephropathy group ( n = 46) and non-contrast-induced nephropathy group ( n = 424) according to the postoperative 48-h serum creatinine levels. The patients' clinical information such as hypertension grade, number and degree of coronary artery stenosis, and death rate was compared. The risk factors for contrast-induced nephropathy were also analyzed. The hypertension grade in the contrast-induced nephropathy group was significantly higher than that in the non-contrast-induced nephropathy group ( P = 0.004). The degree of coronary artery stenosis was significantly more in the contrast-induced nephropathy group compared with the non-contrast-induced nephropathy group ( P = 0.003). The death rate of the contrast-induced nephropathy group (15.8%) was significantly higher than that of the non-contrast-induced nephropathy group (0.6%; P = 0.000). The percentage of patients with abnormal urine microalbumin was significantly bigger in the contrast-induced nephropathy group (62.5%) when comparing to the non-contrast-induced nephropathy group (23.6%; P = 0.00). Besides, there was also significant difference in the emergency/selective operation between the contrast-induced nephropathy group and non-contrast-induced nephropathy group ( P = 0.001). Further, hypertension grade ( P = 0.019), emergency/selective operation ( P = 0.025), degree of coronary artery stenosis ( P = 0.038), eGFR ( P = 0.034), and urine microalbumin ( P = 0.005) were the risk factors for contrast-induced nephropathy. Hypertension grade, emergency/selective operation, degree of coronary artery stenosis, eGFR, and urine microalbumin were the risk factors for contrast-induced nephropathy in over-aged patients receiving coronary angiography and percutaneous coronary intervention, providing guidance for the clinical prevention of contrast-induced nephropathy. Impact statement In this work, we evaluated the risk factors for contrast-induced nephropathy (CIN) in over-aged patients receiving coronary angiography (CAG) and percutaneous coronary intervention (PCI). We found that hypertension grade, emergency/selective operation, degree of coronary artery stenosis, eGFR, and urine microalbumin were the risk factors for CIN in over-aged patients receiving CAG and PCI. This study provides guidance for the clinical prevention of CIN in over-aged patients undergoing coronary intervention, highlighting that a perioperative comprehensive management strategy is needed to improve the prognosis.

A novel &ldquo;nano-crush&rdquo; technique for the management of coronary bifurcation lesions: in vitro bench test analysis and preliminary report on real-world clinical evaluation in patients with one-year angiographic follow-up

AIMS

Although provisional stenting with a single drug-eluting stent has proven clinical efficacy in the treatment of bifurcation stenosis, some patients may require two stents. We propose a novel technique, called "nano-crush", which is easy to perform and can be used in all bifurcation angles.

METHODS AND RESULTS

The feasibility of the nano-crush technique was confirmed in an in vitro bench test and intravascular ultrasound (IVUS) study. Subsequently, 42 patients with de novo coronary bifurcation stenosis were treated by this novel procedure using drug-eluting stents at our centre between January 2008 and December 2015. We experienced procedural success in all (100%) patients without any complications. The primary efficacy endpoint of the one-year incidence of major adverse cardiac events (MACE) was noted in three (7.14%) patients, comprising one case of cardiac death at nine months post procedure and two cases of repeat revascularisation due to in-stent restenosis. There were no cases of periprocedural myocardial infarction or stent thrombosis. Angiographic follow-up at one year indicated intact stent patency in the remaining patients.

CONCLUSIONS

Initial experience with the nano-crush technique demonstrates that it can be performed easily without any procedural complications. Further, the angiographic and clinical follow-up indicates that the nano-crush technique is associated with acceptable clinical outcomes in a real-world scenario.

Duration of dual antiplatelet therapy and outcome in patients with acute coronary syndrome undergoing percutaneous revascularization: A meta-analysis of 11 randomized trials

BACKGROUND

Acute coronary syndromes (ACS) represent a context of higher thrombotic risk, where larger advantages have been achieved by the administration of dual antiplatelet therapy (DAPT). However, the indication of 1 year DAPT after coronary angioplasty for ACS has been supported by an outdated randomized trial (PCI-CURE). In addition, the initial fear of late thrombotic events emerged with first generation drug-eluting stents (DES), that suggested the need of a prolonged DAPT prescription, has been completely overcome by the recent technological evolution of DES, that have shown faster re-endothelization and lower rates of late thrombotic complications. By keeping in mind the balance between thrombotic and bleeding complications, and due to the paucity of dedicated randomized trials, the identification of the optimal duration of DAPT after ACS is still matter of debate, and is therefore the aim of the present meta-analysis.

METHODS

Literature and main scientific session abstracts were searched. The primary efficacy endpoint was mortality, primary safety endpoint was the occurrence of major bleedings. A pre-specified analysis was conducted according to the DAPT strategy allocation (<12 vs standard 12 months duration and 6-12 months vs extended DAPT).

RESULTS

We included 3 RCTs and subanalyses from 8 RCTs, with a total of 17,941 patients. No difference in mortality was observed between shorter vs longer DAPT (OR[95%CI] = 1.11[0.90,1.36], p = 0.33; phet = 0.76). A shorter DAPT duration significantly reduced the rate of major bleeding events (1.5%, vs 1.9%, OR [95%CI] = 0.75 [0.60, 0.94], p = 0.01; phet = 0.43). The reduction in bleeding events was more significant in trials evaluating extended DAPT duration (OR[95%CI] = 0.62[0.45, 0.85], p = 0.003; phet = 0.49). No difference in cardiovascular mortality, myocardial infarction and stent thrombosis was observed with shorter vs standard 12-moth DAPT, whereas a more extended treatment (beyond 1 year), was associated with a significant reduction in recurrent ischemic events. Similar results were observed at a sensitivity analysis conducted according to the type of stent, time to randomization or DAPT duration.

CONCLUSIONS

Based on the current meta-analysis including 17,941 ACS patients undergoing PCI, a short duration of DAPT may be safely considered, with similar rates of recurrent thrombotic complications as compared to the standard 12 months, and similar mortality. A more extended DAPT administration (beyond 1 year) provides benefits in ischemic events, but with an excess in haemorragic complications, with overall neutral effects on mortality.

A Review of Antiplatelet Activity of Traditional Medicinal Herbs on Integrative Medicine Studies

Thrombotic events mainly occurred by platelet activation and aggregation. The vascular occlusion causes serious disease states such as unstable angina, ischemic stroke, and heart attack. Due to the pervading of thrombotic diseases, new antiplatelet drugs are necessary for preventing and treating arterial thrombosis without adverse side effects. Traditional medicinal herbs have been used for the treatment of human ailments for a long time. The clinically useful and safe products from traditional medicinal herbs were identified and developed in numerous pharmacological approaches. A complementary system of traditional medicinal herbs is a good candidate for pharmacotherapy. However, it still has a limitation in its function and efficacy. Thus, it is necessary to study the mode of action of traditional medicinal herbs as alternative therapeutic agents. In this review, we focused on our current understanding of the regulatory mechanisms of traditional medicinal herbs in antiplatelet activity and antithrombotic effect of traditional medicinal herbs on platelet function.

Cerium dioxide-doped carboxyl fullerene as novel nanoprobe and catalyst in electrochemical biosensor for amperometric detection of the CYP2C19*2 allele in human serum

The disposition dose of clopidogrel is different in CYP2C19*2 gene carriers and non-carriers. High-dose clopidogrel has been recommended to overcome a low-responsiveness to clopidogrel in patients with the CYP2C19*2 gene. To guide the choice of clopidogrel dosage and catalyse a development in the field of personalized therapy, we developed an ultrasensitive electrochemical biosensor to detect CYP2C19*2 gene. We constructed a novel assay based on cerium dioxide (CeO₂)-functionalized carboxyl fullerene (c-C₆₀) supported by Pt nanoparticles (c-C₆₀/CeO₂/PtNPs) for signal amplification. Au nanoparticles @ Fe-MIL-88NH₂ (AuNPs@Fe-MOFs) were synthesized by one-step method as the support platform to enhance the conductivity and immobilize more biotin-modified capture probe (bio-CP) through the superior affinity and specificity between streptavidin and biotin. c-C₆₀/CeO₂/PtNPs were labeled with signal probe to form the signal label. After the sandwich reaction of CYP2C19*2 gene between capture probe and the signal label, a distinguishing electrochemical signal from the catalysis of H₂O₂ by signal label would be observed. Amperometry was applied to record electrochemical signals. Under optimized conditions, the approach showed a good linear dependence between current and the logarithm of CYP2C19*2 gene concentrations in the range of 1 fM to 50nM with a low detection limit of 0.33fM (S/N = 3). The proposed method showed good specificity to target DNA compared with possible interfering substances. More importantly, the fabricated biosensor achieved accurate quantitative detection of CYP2C19*2 gene in human serum samples demonstrated by excellent correlations with standard DNA sequencing and provided a promising strategy for electrochemical biosensor detection of other gene mutations.

Issues related to renal artery angioplasty and stenting

Renal artery stenosis may play a significant role in the pathogenesis of secondary hypertension, renal dysfunction, and flash pulmonary edema. Currently correction of renal arterial inflow stenosis is reserved for resistant hypertension patients who have failed maximal medical therapy, have worsening renal function and/or unexplained proximal congestive failure. With the recent advances in minimally invasive percutaneous stent placement techniques, open surgical revascularization has been largely replaced by renal artery stenting. The potential benefit of revascularization seemed intuitive; however, the initial enthusiasm and rise in the number of percutaneous interventions have been tempered by many subsequent negative randomized clinical trials that failed to prove the proposed benefits of the percutaneous intervention. The negative randomized trial results have fallen under scrutiny due to trial design concerns and inconsistent outcomes of these studies compared to pivotal trials undertaken under US Food and Drug Administration scrutiny. Treatment of atherosclerotic renal artery occlusive disease has become one of the most debatable topics in the field of vascular disease. The results from recent randomized clinical trials of renal artery stenting have basically limited the utilization of the procedure in many centers, but not every clinical scenario was covered in those trials. There are potential areas for improvement focusing mainly on procedural details and patient selection with respect to catheter based treatment of atherosclerotic renal artery stenosis. We believe, limiting patient selection, enrollment criteria and outcomes measured functioned to reduce the benefit of renal artery stenosis stenting by not enrolling patients likely to benefit. Future studies incorporating potential procedural improvements and that include patients more likely to benefit from renal stenting than were included in ASTRAL and CORAL are needed to more carefully examine specific patient subgroups so that “the baby is not thrown out with the bath water.” We also discuss several other concerns related to renal artery stenting which include diagnostic, procedure, indication, and reimbursement issues.

Issues related to renal artery angioplasty and stenting

Renal artery stenosis may play a significant role in the pathogenesis of secondary hypertension, renal dysfunction, and flash pulmonary edema. Currently correction of renal arterial inflow stenosis is reserved for resistant hypertension patients who have failed maximal medical therapy, have worsening renal function and/or unexplained proximal congestive failure. With the recent advances in minimally invasive percutaneous stent placement techniques, open surgical revascularization has been largely replaced by renal artery stenting. The potential benefit of revascularization seemed intuitive; however, the initial enthusiasm and rise in the number of percutaneous interventions have been tempered by many subsequent negative randomized clinical trials that failed to prove the proposed benefits of the percutaneous intervention. The negative randomized trial results have fallen under scrutiny due to trial design concerns and inconsistent outcomes of these studies compared to pivotal trials undertaken under US Food and Drug Administration scrutiny. Treatment of atherosclerotic renal artery occlusive disease has become one of the most debatable topics in the field of vascular disease. The results from recent randomized clinical trials of renal artery stenting have basically limited the utilization of the procedure in many centers, but not every clinical scenario was covered in those trials. There are potential areas for improvement focusing mainly on procedural details and patient selection with respect to catheter based treatment of atherosclerotic renal artery stenosis. We believe, limiting patient selection, enrollment criteria and outcomes measured functioned to reduce the benefit of renal artery stenosis stenting by not enrolling patients likely to benefit. Future studies incorporating potential procedural improvements and that include patients more likely to benefit from renal stenting than were included in ASTRAL and CORAL are needed to more carefully examine specific patient subgroups so that "the baby is not thrown out with the bath water." We also discuss several other concerns related to renal artery stenting which include diagnostic, procedure, indication, and reimbursement issues.

Management of anticoagulant and antiplatelet therapy in patients undergoing interventional pulmonary procedures

There has been great progress in antithrombotic therapy over the past several years. Its use has increased with the advent of novel anticoagulants, as these medications do not require frequent blood tests for monitoring. Antithrombotic therapy is aimed at reducing the risk of thromboembolic events in patients with atrial fibrillation, coronary artery disease, deep vein thrombosis, valvular heart disease and pulmonary embolism. These patients are often critically ill and frequently undergo urgent interventions requiring discontinuation of anticoagulant or antiplatelet therapy which can increase the risk of thrombosis; however, continuing these agents can lead to increased risk of haemorrhage.

The purpose of this article is to summarise the literature surrounding the safety of using antiplatelet and anticoagulant therapies in patients undergoing interventional pulmonary procedures.

Available studies suggest some antithrombotic agents may be used in interventional pulmonary procedureshttp://ow.ly/vSF030bRqjt

Cardiac Evaluation and Monitoring of Patients Undergoing Noncardiac Surgery

Surgical management of disease has a tremendous impact on our health system. Millions of people worldwide undergo surgeries every year. Cardiovascular complications in the perioperative period are one of the most common events leading to increased morbidity and mortality. Although such events are very small in number, they are associated with a high mortality rate making it essential for physicians to understand the importance of perioperative cardiovascular risk assessment and evaluation. Its involves a detailed process of history taking, patient's medical profile, medications being used, functional status of the patient, and knowledge about the surgical procedure and its inherent risks. Different risk assessment tools and calculators have also been developed to aid in this process, each with their own advantages and limitations. After such a comprehensive evaluation, a physician will be able to provide a risk assessment or it may all lead to further testing if it is believed that a change in management after such testing will help to reduce perioperative morbidity and mortality. There is extensive literature on the significance of multiple perioperative testing modalities and how they can change management. The purpose of our review is to provide a concise but comprehensive analysis on all such aspects of perioperative cardiovascular risk assessment for noncardiac surgeries and provide a basic methodology toward such assessment and decision making.

Functional Nanoarchitectures For Enhanced Drug Eluting Stents

Different strategies have been investigated to allow for optimum duration and conditions for endothelium healing through the enhancement of coronary stents. In this study, a nanoarchitectured system is proposed as a surface modification for drug eluting stents. Highly oriented nanotubes were vertically grown on the surface of a new Ni-free biocompatible Ti-based alloy, as a potential material for self-expandable stents. The fabricated nanotubes were self-grown from the potential stent substrate, which are also proposed to enhance endothelial proliferation while acting as drug reservoir to hinder Vascular Smooth Muscle Cells (VSMC) proliferation. Two morphologies were synthesized to investigate the effect of structure homogeneity on the intended application. The material was characterized by field-emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). Nanoindentation technique was used to study the mechanical properties of the fabricated material. Cytotoxicity and proliferation studies were performed and compared for the two fabricated nanoarchitectures, versus smooth untextured samples, using in-vitro cultured endothelial cells. Finally, the drug loading capacity was experimentally studied and further supported by computational modeling of the release profile.

Renovascular heart failure: heart failure in patients with atherosclerotic renal artery disease

Atherosclerotic renal artery disease presents with a broad spectrum of clinical features, including heart failure as well as hypertension, and renal failure. Although recent randomized controlled trials failed to demonstrate renal artery stenting can reduce blood pressure or the number of cardiovascular or renal events more so than medical therapy, increasing attention has been paid to flash pulmonary edema and congestive heart failure associated with atherosclerotic renal artery disease. This clinical entity "renovascular heart failure" is diagnosed retrospectively. Given the increasing global burden of heart failure, this review highlights the background and catheter-based therapeutic aspects for renovascular heart failure.

Reduction in incomplete stent apposition area caused by jailed struts after single stenting at left main bifurcation lesions: micro-CT analysis using a three-dimensional elastic bifurcated coronary artery model

Stent struts protruding into ostial side branch called “jailed strut” at bifurcation lesions is a likely cause of thrombus formation. We aimed to investigate the influences of multiple kissing balloon inflation (KBI) for stent expansion, and stent platform design, respectively, on the reduction of incomplete stent apposition area (ISA area) caused by jailed struts at a side-branch ostium, using a three-dimensional elastic left main (LM) bifurcated coronary artery model. The referenced LM bifurcation angle data of 209 patients were stratified by tertiles focusing on the angle between the LM trunk (LMT) and left anterior descending artery (LAD). A bifurcation model was fabricated with angles of 129°, 122.2°, and 76.4° for LMT–LAD, LMT–left circumflex (LCx), and LAD–LCx, respectively, and with diameters of 5, 3.75, and 3.5 mm for LMT, LAD, and LCx, respectively; these diameters fulfill Murray’s law. A 75 % stenosis was included along the LMT. One-time and three-time KBIs were conducted using two-link Nobori and three-link Xience Xpedition (n = 6 each). The ISA area was quantified using micro-CT. Three-time KBI was effective in reducing the ISA area compared with one-time KBI for both the Nobori (p = 0.05) and Xience Xpedition (p = 0.07). The ISA area was smaller in the Nobori than in the Xience Xpedition, both in one-time and three-time KBI (one-time KBI: p = 0.003; three-time KBI: p = 0.001). Our findings of this study on reducing the ISA area by focusing on an interventional technique and stent design may help to improve coronary bifurcation intervention for a possibly better long-term clinical outcome.

Cytochrome P450-derived epoxyeicosatrienoic acids and coronary artery disease in humans: a targeted metabolomics study

Cytochrome P450 (CYP)-derived epoxyeicosatrienoic acids (EETs) exhibit potent cardiovascular protective effects in preclinical models, and promoting the effects of EETs has emerged as a potential therapeutic strategy for coronary artery disease (CAD). The relationship between circulating EET levels and CAD extent in humans, however, remains unknown. A panel of free (unesterified) plasma eicosanoid metabolites was quantified in 162 patients referred for coronary angiography, and associations with extent of CAD [no apparent CAD (N = 39), nonobstructive CAD (N = 51), and obstructive CAD (N = 72)] were evaluated. A significant relationship between free EET levels and CAD extent was observed (P = 0.003) such that the presence of obstructive CAD was associated with lower circulating EET levels. This relationship was confirmed in multiple regression analysis where CAD extent was inversely and significantly associated with EET levels (P = 0.013), and with a biomarker of EET biosynthesis (P < 0.001), independent of clinical and demographic factors. Furthermore, quantitative enrichment analysis revealed that these associations were the most pronounced compared with other eicosanoid metabolism pathways. Collectively, these findings suggest that the presence of obstructive CAD is associated with lower EET metabolite levels secondary to suppressed EET biosynthesis. Novel strategies that promote the effects of EETs may have therapeutic promise for patients with obstructive CAD.

Update on intervention versus medical therapy for atherosclerotic renal artery stenosis

Atherosclerotic renal artery stenosis is known to be one of the most common causes of secondary hypertension, and early nonrandomized studies suggested that renal artery stenting (RASt) improved outcomes. The vascular community embraced this less invasive treatment alternative to surgery, and RASt increased in popularity during the late 1990s. However, recent randomized studies have failed to show a benefit regarding blood pressure or renal function when RASt was compared with best medical therapy, creating significant concerns about procedural efficacy. In the wake of these randomized trial results, hypertension and renal disease experts along with vascular interventional specialists now struggle with how to best manage atherosclerotic renal artery stenosis. This review objectively analyzes the current literature and highlights each trial's design weaknesses and strengths. We have provided our recommendations for contemporary treatment guidelines based on our interpretation of the available empirical data.

Monitoring aspirin therapy in children after interventional cardiac catheterization: laboratory measures, dose response, and clinical outcomes

Very few studies have investigated dose response of aspirin and agreement of different platelet function assays in children. One hundred five children were studied at baseline and after interventional cardiac catheterization during aspirin treatment and, in cases of aspirin resistance (AR), after dose increase. Results from arachidonate-induced aggregation (AA) were compared with aggregation induced by ADP, PFA-100 closure times (CTs), urinary 11-dehydro-thromboxane B2 (urinary 11-dhTxB2) levels, and Impact-R % surface coverage. Aspirin at 2-5 mg/kg/day inhibited platelet function in a large majority. While 19 % showed bruising and mild epistaxis, no thrombotic complications were recorded. AR was detected by AA in seven children (6.7 %). After dose increase, the majority showed inhibition by aspirin. Infants had higher urinary 11-dhTxB2 baseline levels; this assay showed some correlation with AA. Both assays manifested high sensitivity and specificity for aspirin while inferior results were found for the other assays. With the PFA-100, 15.2 % of patients were found to have AR, but this corresponded to AR by AA in only one of seven children.

CONCLUSION

While there was poor agreement among assays, AA and urinary 11-dhTxB2 show good specificity for the monitoring of aspirin therapy in children. Aspirin at 2-5 mg/kg inhibits platelet function; AR in children is rare and can be overcome by dose increase.

Optimal Duration of Dual Antiplatelet Therapy After DES Implantation: A Meta-Analysis of 11 Randomized Trials

Despite new-generations of drug-eluting stents (DESs), the optimal duration of dual antiplatelet therapy (DAPT) remains controversial. We performed a meta-analysis of randomized trials (RTs) evaluating the effectiveness and safety of shorter versus longer DAPT duration strategies in patients undergoing percutaneous coronary interventions with DES. Literature and main scientific session abstracts were searched. The primary end point was mortality. Secondary end points were (1) cardiovascular mortality, (2) nonfatal myocardial infarction, (3) definite/probable stent thrombosis (ST), and (4) major bleedings. We included 11 RTs (n = 32 372 patients). Shorter DAPT duration reduced mortality (odds ratio, OR [95% confidence interval, CI] = 0.85 [0.71-1], P = .05; p heterogeneity = 0.91). Similar results were observed when comparing 3 to 6 versus 12 months DAPT, while a significant increase in recurrent ischemic events was found for 6 to 12 months DAPT versus extended treatment (myocardial infarction: OR [95%CI] = 1.66 [1.37-2], P < .00001; phet = 0.13 and ST: OR [95%CI] = 2.47 [1.72-3.45], P < .00001; phet = 0.12), however, counterbalanced by a significant reduction in major bleeding (OR [95%CI] = 0.60 [0.47-0.76], P < .0001; phet = 0.38) and a trend in lower mortality. Thus, among selected patients undergoing DES implantation, a shorter DAPT strategy is associated with reduction in mortality and major bleeding but a higher risk of myocardial infarction and ST. A short duration (3-6 months) of DAPT appears as the safest strategy, while a prolonged duration (24-36 months) reduces thrombotic complications but with an excess in major bleeding complications.

Novel oral P2Y12 inhibitor prasugrel vs. clopidogrel in patients with acute coronary syndrome: evidence based on 6 studies

BACKGROUND

Whether prasugrel can take the place of clopidogrel for patients with acute coronary syndrome (ACS) is not clear. The aim of this study was to perform a meta-analysis for systematically reviewing the evidence on prasugrel in comparison to clopidogrel in patients with ACS.

MATERIAL/METHODS

Relevant prospective and retrospective studies were searched in databases. Six studies were finally included. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated to assess all causes of death, myocardial infarction (MI), stroke, major bleeding, major/minor bleeding, and stent thrombosis (for PCI performed).

RESULTS

Compared with clopidogrel, prasugrel had similar risks of all cause of death (Pooled RR: 0.83; 95% CI: 0.64-1.06, p=0.14, I2=55%), MI (Pooled RR: 0.86; 95% CI: 0.71-1.04, p=0.12) and stroke (pooled RR: 0.88; 95% CI: 0.70-1.10, p=0.25). However, prasugrel was associated with significantly higher risk of both major bleeding (Pooled RR: 1.19; 95% CI: 0.99-1.44, p=0.06, I2=0%) and the risk of total major and minor bleeding (Pooled RR: 1.30; 95% CI: 1.15-1.48, p<0.0001, I2=0%). For the patients who underwent percutaneous coronary intervention (PCI), prasugrel was associated with significantly lower risk of stent thrombosis (Pooled RR: 0.47; 95% CI: 0.34-0.61, p<0.00001, I2=0%).

CONCLUSIONS

Prasugrel has similar effects as clopidogrel in terms of all causes of death, MI, and stroke in ACS patients. For the patients who underwent PCI, prasugrel contributes to lower risk of stent thrombosis. However, prasugrel is associated with significantly higher risk of bleeding. For the patients with active pathological bleeding or a history of stroke and/or TIA, prasugrel should not be recommended.

Technical discussion of diagnostic angiography and intervention of atherosclerotic renal artery stenosis

Renal artery stenting remains an important adjuvant treatment for true-resistant hypertension, although recent disappointing randomized trials highlight the importance of careful patient selection. Safe and successful renal interventions begin with critical core knowledge regarding renal artery anatomy and understanding the often hostile nature of the parent vessel (pararenal aorta). Armed with fundamental knowledge about anatomy and renal ostial disease pathology, it becomes easier to understand the advantages of less traumatic access techniques and how low-profile contemporary flexible stents have enhanced outcomes. In addition to suggested techniques based on detailed understanding of the vessel architecture and pathology, we will review the current available US Food and Drug Administration-approved balloon-expandable on-label renal stents and discuss the role of intravascular ultrasound for definition of lesion severity, stent sizing, and stent apposition. The durability of renal stenting will also be discussed, as will the velocity criteria for duplex surveillance. Lastly, the current empirical data related to renal embolic protection is provided, along with insight into technical issues in this domain.

StentBoost Visualization for the Evaluation of Coronary Stent Expansion During Percutaneous Coronary Interventions

Introduction

Inadequate stent implantation is associated with stent thrombosis and restenosis. StentBoost can enhance stent visualization and evaluate stent expansion. Currently, there are limited comparison studies between StentBoost and intravascular ultrasound (IVUS). We aimed to test the correlation and agreement between IVUS and StentBoost measurements.

Methods

From December 2010 to December 2011, 38 patients (54 stents) were analyzed using IVUS and StentBoost. Minimal stent diameter and proximal and distal edge stent diameter were compared between imaging techniques using Pearson correlation and Bland–Altman scatter plot.

Results

There was good correlation between StentBoost and IVUS measurements regarding minimal stent diameter (p < 0.001 in all stent portions) and an optimal agreement between IVUS and StentBoost, while lesser agreement was found between IVUS and quantitative coronary angiography.

Conclusion

The assessment of stent implantation using StentBoost showed an adequate correlation and agreement with IVUS. This easily applicable angiographic technique can be used to guide stent implantation.

Electronic supplementary material

The online version of this article (doi:10.1007/s40119-013-0023-2) contains supplementary material, which is available to authorized users.

Blood pressure response to renal artery stenting in 901 patients from five prospective multicenter FDA-approved trials

BACKGROUND

Renal artery stent revascularization is commonly used for renovascular hypertension. Clinical predictors associated with blood pressure (BP) improvement after renal artery stent revascularization are not well understood.

METHODS

Patient-level data from 901 patients in five prospective multicenter Food and Drug Administration-approved investigational device exemption studies of renal artery stent revascularization was pooled. BP response was defined as reduction of systolic BP (SBP) by >10 mm Hg. Stent patency was defined within each study. Associations of BP reduction were determined by logistic regression.

RESULTS

Of 901 patients, complete outcome information was available in 527. Of these, 212/527 (40%) were male, mean age was 63 ± 13 years, 196/544 (36%) were diabetic and 504/527 (96%) had a SBP ≥ 140 mm Hg or DBP ≥ 90 mm Hg at baseline. Compared to baseline, 9-month systolic (164 ± 21 mm Hg vs. 146 ± 22 mm Hg, P < 0.0001) and diastolic (79 ± 13 mm Hg vs. 76 ± 12 mm Hg, P < 0.0001) BP declined significantly. Nine-month stent patency was 90% (305/339). In a univariate analysis, baseline SBP >150 mm Hg (OR = 4.09, CI = 2.74-6.12, P < 0.0001) was positively associated with BP response following renal artery stent revascularization. In a multivariable analysis, baseline SBP remained associated with a positive BP response (OR = 1.76, CI = 1.53-2.03, P < 0.0001).

CONCLUSIONS

In the largest pooled dataset of patients treated with renal artery stent revascularization, SBP and DBP were significantly lower at 9-months. Elevated baseline SBP (>150 mm Hg) was strongly associated with BP reduction after the procedure.