Adam J. Brown

Percutaneous Coronary Intervention Using Drug-Eluting Stents Versus Coronary Artery Bypass Grafting for Unprotected Left Main Coronary Artery Stenosis: A Meta-Analysis of Randomized Trials

Background—Current guidelines suggest that coronary artery bypass grafting (CABG) should be the preferred revascularization method for unprotected left main coronary artery stenosis. In light of evidence from recent randomized trials, we assessed whether percutaneous coronary intervention (PCI) using drug-eluting stents is as safe and effective as CABG for the treatment of unprotected left main coronary artery disease. Methods and Results—Digital databases and manual searches were performed for randomized trials comparing PCI and CABG for unprotected left main coronary artery stenosis. Among 3887 potentially relevant studies, 5 met inclusion criteria. The primary safety end point was defined as the composite of all-cause death, myocardial infarction, or stroke. Secondary end points included a clinical effectiveness composite, which was defined as all-cause death, myocardial infarction, stroke, or repeat revascularization. Summary estimates were obtained using random-effects modeling. In total, 4594 patients were included in the analysis. There was no significant difference in the primary safety end point between the revascularization strategies (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.79–1.17; P=0.73). However, when compared with CABG, PCI was less effective (OR, 1.36; 95% CI, 1.18–1.58; P<0.001) because of significantly higher rates of repeat revascularization (OR, 1.85; 95% CI, 1.53–2.23; P<0.001). The incidence of all-cause death (OR, 1.03; 95% CI, 0.78–1.35; P=0.61), myocardial infarction (OR, 1.46; 95% CI, 0.88–2.45; P=0.08), and stroke (OR, 0.88; 95% CI, 0.39–1.97; P=0.53) did not differ between PCI and CABG. Conclusions—PCI using drug-eluting stents and CABG are equally safe methods of revascularization for patients at low surgical risk with significant unprotected left main coronary artery stenosis. However, CABG is associated with significantly lower rates of repeat revascularization.

Association of epicardial adipose tissue and high-risk plaque characteristics: A systematic review and meta-analysis

Background Epicardial adipose tissue (EAT) is hypothesized to alter atherosclerotic plaque composition, with potential development of high‐risk plaque (HRP). EAT can be measured by volumetric assessment (EAT‐v) or linear thickness (EAT‐t). We performed a systematic review and random‐effects meta‐analysis to assess the association of EAT with HRP and whether this association is dependent on the measurement method used. Methods and Results Electronic databases were systematically searched up to October 2016. Studies reporting HRP by computed tomography or intracoronary imaging and studies measuring EAT‐v or EAT‐t were included. Odds ratios were extracted from multivariable models reporting the association of EAT with HRP and described as pooled estimates with 95% confidence intervals (CIs). Analysis was stratified by EAT measurement method. Nine studies (n=3772 patients) were included with 7 measuring EAT‐v and 2 measuring EAT‐t. Increasing EAT was significantly associated with the presence of HRP (odds ratio: 1.26 [95% CI, 1.11–1.43]; P<0.001). Patients with HRP had higher EAT‐v than those without (weighted mean difference: 28.3 mL [95% CI, 18.8–37.8 mL]; P<0.001). EAT‐v was associated with HRP (odds ratio: 1.19 [95% CI, 1.06–1.33]; P<0.001); however, EAT‐t was not (odds ratio: 3.09 [95% CI, 0.56–17]; P=0.2). Estimates remained significant when adjusted for small‐study effect bias (odds ratio: 1.13 [95% CI, 1.03–1.28]; P=0.04). Conclusions Increasing EAT is associated with the presence of HRP, and patients with HRP have higher quantified EAT‐v. The association of EAT‐v with HRP is significant compared with EAT‐t; however, a larger scale study is still required, and further evaluation is needed to assess whether EAT may be a potential therapeutic target for novel pharmaceutical agents. Clinical Trial Registration URL: https://www.crd.york.ac.uk/. Unique identifier: CRD42017055473.

Midterm Safety and Efficacy of ABSORB Bioresorbable Vascular Scaffold Versus Everolimus-Eluting Metallic Stent: An Updated Meta-Analysis

One of the principal aims in developing bioresorbable vascular scaffolds (BVS) was reduction in the long-term risk of stent-related complications, including very late (>1 year) stent thrombosis (ST). However, recent data suggest that the risk of very late ST may persist, or even be increased, in BVS

Implantation of bioresorbable vascular scaffolds following acute coronary syndrome is associated with reduced early neointimal growth and strut coverage.

AIMSnRegistry data have suggested higher than anticipated rates of scaffold thrombosis following bioresorbable vascular scaffold (BVS) implantation. We examined early neointimal growth and strut coverage in BVS to ascertain whether this was affected by clinical presentation.nnnMETHODS AND RESULTSnPatients undergoing optical coherence tomography (OCT)-guided BVS implantation, either for stable angina (SA) or acute coronary syndrome (ACS), were recruited to this observational study. Repeat OCT was performed at follow-up (median 74 days), and scaffolds analysed at 1 mm longitudinal intervals for scaffold/flow area, scaffold apposition, neointimal growth and strut coverage. Twenty-nine BVS were included in the analysis (62% implanted following ACS). There were no differences in baseline patient/lesion characteristics. All BVS achieved >90% predicted scaffold area with only 1.64% of struts classified as incompletely apposed, compared with 0.47% at follow-up (p=0.006). Reductions in mean scaffold (-4.0%, p=0.01) and flow (-8.4%, p<0.001) areas were observed at follow-up, with larger reductions in mean flow area in stable patients (-14.5±14.2 vs. -4.9±7.9%, p=0.03). ACS patients had reduced neointimal growth (0.51±0.18 vs. 0.87±0.37 mm2, p=0.002), and increased percentage of uncovered struts (2.68±1.67 vs. 1.43±0.87%, p=0.015).nnnCONCLUSIONSnEarly neointimal growth and strut coverage are reduced following ACS in patients receiving BVS. These results may, in part, explain the high rates of ST in registry data.

Subclinical Leaflet Thrombosis in Transcatheter Aortic Valve Replacement Detected by Multidetector Computed Tomography ― A Review of Current Evidence ―

Subclinical leaflet thrombosis (SLT) following transcatheter aortic valve replacement (TAVR) has been increasingly recognized. SLT has the hallmark features of hypo-attenuated leaflet thickening (HALT) on multidetector computed tomography (MDCT), which may result in hypoattenuation affecting motion (HAM). The actual prevalence of this condition is uncertain, with limited observational registries. SLT has caught the attention of the cardiovascular community because of concerns regarding its clinical sequelae, specifically the potential increased incidence of cerebrovascular events. There are available, albeit sparse, data to suggest that when left untreated, SLT may lead to valve deterioration with potential hemodynamic compromise and potentially clinically overt prostheses thrombosis. Some clinicians have opted to treat patients with SLT with anticoagulation. Although anticoagulation may be a rational treatment option, little data exist on the safety and efficacy of this treatment. This is particularly important considering TAVR patients also have higher bleeding risk than the standard population. In this review, we aim to summarize the current evidence on SLT, explore its pathophysiological mechanism, discuss the current treatment options and future trials that may clarify the optimal antithrombotic strategies of SLT.

High-Sensitivity Troponin I is Associated With High-Risk Plaque and MACE in Stable Coronary Artery Disease

Cardiac troponin I (cTnI) is a marker of myocardial injury, and improvements to assay sensitivity allow for precise quantification at extremely low concentrations. In stable coronary artery disease (CAD), high-sensitivity (hs)-cTnI concentrations are independently associated with subsequent cardiac

Novel bioabsorbable polymer and polymer-free metallic drug-eluting stents.

The introduction of drug-eluting stents (DES) significantly reduced angiographic restenosis and the clinical need for revascularization following percutaneous coronary intervention. However, concerns remain regarding the long-term safety and efficacy of DES. The use of durable polymers for drug elution that have limited biocompatibility is thought to contribute toward DES failure, by promoting an adverse local inflammatory response and vascular toxicity. Biodegradable polymer and polymer-free metallic stents represent two novel technological solutions to this challenging clinical problem. This review summarizes the available clinical evidence supporting the use of either biodegradable polymer or polymer-free DES platforms.

Continuous and minimally-interrupted direct oral anticoagulant are both safe compared with vitamin K antagonist for atrial fibrillation ablation: An updated meta-analysis

BACKGROUNDnThe appropriate and safe peri-procedural anticoagulation schedule for patients on a direct oral anticoagulant (DOAC) undergoing AF ablation is not known. We aimed to evaluate the safety and efficacy of both continuous and minimally-interrupted novel oral anticoagulant (DOAC) strategies compared with uninterrupted vitamin K antagonist (VKA) for atrial fibrillation (AF) ablation.nnnMETHODSnWe searched electronic databases for randomized or prospective controlled observational studies comparing DOAC (continuous or interrupted) versus uninterrupted VKA. The primary endpoint was major bleeding. Secondary endpoints were total bleeding (composite of major and minor bleeding) and symptomatic thromboembolism. Data were analyzed by random-effects modeling and sensitivity analyses performed according to study design and peri-procedural DOAC schedule.nnnRESULTSnThirteen studies (4 randomized, 9 observational) with 5463 patients were included in final analysis (45% on DOAC). DOAC was associated with less major bleeding compared with VKA in pooled randomized studies (odds ratio [OR] 0.27, 95% confidence interval [CI] 0.09-0.80, pu202f=u202f0.03, I2u202f=u202f0%), however there was no difference on overall analyses (OR 0.70, 95% CI 0.39-1.24, pu202f=u202f0.22, I2u202f=u202f27%). When stratified by DOAC dose schedule, there was no difference in major bleeding for continuous DOAC (OR 0.48, 95% CI 0.21-1.11, pu202f=u202f0.09, I2u202f=u202f6%) or minimally-interrupted DOAC (OR 0.81, 95% CI 0.37-1.76, pu202f=u202f0.60, I2u202f=u202f43%) compared with VKA. There was no difference between DOAC and VKA for risk of total bleeding (pu202f=u202f0.20) or symptomatic thromboembolism (pu202f=u202f0.78).nnnCONCLUSIONnContinuous and minimally-interrupted DOAC are both safe and non-inferior peri-procedural anticoagulation strategies compared with uninterrupted VKA for AF ablation. DOAC in general is associated with reduced major bleeding as demonstrated in pooled randomized studies.

A Practical Guide for Fractional Flow Reserve Guided Revascularisation

The presence and extent of myocardial ischaemia is a major determinant of prognosis and benefit from revascularisation in patients with stable coronary artery disease. Fractional Flow Reserve (FFR) is accepted as the reference standard for invasive assessment of ischaemia. Its ability to detect lesion specific ischaemia makes it a useful test in a wide range of patient and lesion subsets, with FFR guided intervention improving clinical outcomes and reducing health care costs compared to assessment with coronary angiography alone. This article will review the basic principles in FFR, practical tips in FFR guided revascularisation and the role of emerging non-hyperaemic indices of ischaemia.

Optical coherence tomography imaging of coronary atherosclerosis is affected by intraobserver and interobserver variability

Aims Optical coherence tomography (OCT) has emerged as a novel imaging modality that allows plaque classification through identification of features including lipid, calcification and fibrous cap. However, subtle changes in light attenuation as the optical beam traverses the plaque in vivo are challenging to interpret and data on strength of observer agreement are minimal. Thus, we sought to assess both the intra and interobserver variability for plaque composition/classification using OCT. Methods OCT imaging was performed in 50 patients prior to percutaneous coronary intervention. Analysis was performed offline by two independent, experienced OCT operators. Target lesion luminal dimensions and plaque composition were assessed at minimal luminal area (MLA) and at five 1-mm longitudinal intervals proximal and distal to the MLA. An OCT thin-capped fibroatheroma (OCT-TCFA) was defined as greater than 90 degree lipid arc with minimal fibrous cap thickness less than 0.85u200a&mgr;m. Results Overall, 540 frames of OCT were included and exceptional consistency was seen for all measures of luminal geometry [all intraclass correlation coefficients (ICC) >0.97, Pu200a<u200a0.001]. Intraobserver agreements for calcification and lipid arc were strong (both ICC >0.84, Pu200a<u200a0.001), whereas interobserver agreement was higher for calcium (ICC 0.76) than lipid (ICC 0.69). Interobserver agreement of minimal fibrous cap thickness was moderate (ICC 0.52, 95% confidence interval 0.45–0.58, Pu200a<u200a0.001], but improved as cap thickness decreased. Overall, intra and interobserver agreements for OCT-defined plaque classification were strong (Ku200a=u200a0.86 and 0.71, respectively). Conclusion Luminal dimensions and plaque compositional features identified by OCT are minimally affected by observer variability, permitting dependable plaque classification.