Percutaneous left atrial appendage occlusion aims to reduce the risk of stroke in patients with AF, particularly those who are not good candidates for systemic anticoagulation. The procedure has been ...studied in large international randomised trials and registries and was approved by the National Institute for Health and Care Excellence in 2014 and by NHS England in 2018. This position statement summarises the evidence for left atrial appendage occlusion and presents the current indications. The options and consensus on best practice for pre-procedure planning, undertaking a safe and effective implant and appropriate post-procedure management and follow-up are described. Standards regarding procedure volume for implant centres and physicians, the role of multidisciplinary teams and audits are highlighted.
The association of frailty with coronary plaque phenotype among older patients with non-ST-elevation acute coronary syndrome (NSTEACS) is not known. The aim of this study was to evaluate the ...association of frailty with coronary plaque phenotype among older patients with NSTEACS.
Older patients with NSTEACS who underwent invasive angiography were recruited. Frailty was measured using the Fried frailty score. Following angiography, patients underwent greyscale and virtual histology intravascular ultrasound (VH-IVUS) imaging. Of the 90 patients, 26 (28.9%) were robust, 49 (54.4%) patients were pre-frail, and 15 (16.7%) were frail. Mean age was 80.9±3.8 years; 59 (65.6%) were male. Compared to robust patients, the pre-frail group had a significantly greater presence of high-risk lesions including VH thin-cap fibroatheroma (TCFA, p=0.011), minimum lumen area (MLA) ≤4 mm2 (p=0.016), TCFA+MLA ≤4 mm2 (p=0.005), TCFA+plaque burden (PB) ≥70% (p=0.005) and TCFA+PB ≥70%+MLA ≤4 mm2 (p=0.003). By age- and sex-adjusted logistic regression analysis, frailty was found to be strongly and independently associated with the presence of TCFA (odds ratio OR 2.81, 95% confidence interval CI:1.06-7.48, p=0.039).
This is the first study to report the relationship between frailty phenotype and coronary plaque morphology among frail older NSTEACS patients. ClinicalTrials.gov Identifier: NCT01933581.
Although plaque rupture is responsible for most myocardial infarctions, few high-risk plaques identified by intracoronary imaging actually result in future major adverse cardiovascular events (MACE). ...Nonimaging markers of individual plaque behavior are therefore required. Rupture occurs when plaque structural stress (PSS) exceeds material strength. We therefore assessed whether PSS could predict future MACE in high-risk nonculprit lesions identified on virtual-histology intravascular ultrasound.
Baseline nonculprit lesion features associated with MACE during long-term follow-up (median: 1115 days) were determined in 170 patients undergoing 3-vessel virtual-histology intravascular ultrasound. MACE was associated with plaque burden ≥70% (hazard ratio: 8.6; 95% confidence interval, 2.5-30.6; P<0.001) and minimal luminal area ≤4 mm(2) (hazard ratio: 6.6; 95% confidence interval, 2.1-20.1; P=0.036), although absolute event rates for high-risk lesions remained <10%. PSS derived from virtual-histology intravascular ultrasound was subsequently estimated in nonculprit lesions responsible for MACE (n=22) versus matched control lesions (n=22). PSS showed marked heterogeneity across and between similar lesions but was significantly increased in MACE lesions at high-risk regions, including plaque burden ≥70% (13.9±11.5 versus 10.2±4.7; P<0.001) and thin-cap fibroatheroma (14.0±8.9 versus 11.6±4.5; P=0.02). Furthermore, PSS improved the ability of virtual-histology intravascular ultrasound to predict MACE in plaques with plaque burden ≥70% (adjusted log-rank, P=0.003) and minimal luminal area ≤4 mm(2) (P=0.002). Plaques responsible for MACE had larger superficial calcium inclusions, which acted to increase PSS (P<0.05).
Baseline PSS is increased in plaques responsible for MACE and improves the ability of intracoronary imaging to predict events. Biomechanical modeling may complement plaque imaging for risk stratification of coronary nonculprit lesions.
ABSTRACT
A 74-year-old man with no co-morbidities presented to hospital with a 3-day history of diarrhoea and vomiting. He met the modified Duke’s criteria for definite infective endocarditis and was ...immediately started on an intravenous antibiotic. Over Days 1–9, he developed renal failure. On Day 10, he was transferred to a tertiary hospital for mitral valve replacement. However, he tested positive for SARS-CoV-2 on arrival at the tertiary hospital, which delayed his surgery. He underwent bi-weekly nasopharyngeal swabs for SARS-CoV-2 with a plan to operate as soon as he tested negative, or as soon as his incubation period for COVID-19 pneumonia had elapsed. Unfortunately, he died on Day 31 from acute respiratory distress syndrome secondary to COVID-19 pneumonia. We describe the challenges in deciding on the optimal timing for valve replacement. We conclude by suggesting that earlier valve replacement may result in better outcomes.
Computed tomography (CT) is used routinely for coronary angiography, and higher-risk features of plaques can also be identified. However, the ability of CT to discriminate individual plaque ...components and classify plaques according to accepted histological definitions is unknown.
We first determined CT attenuation ranges for individual plaque components using combined in vivo CT coregistered with virtual histology intravascular ultrasound (VH-IVUS) in 108 plaques from 57 patients. Comparison with contrast attenuation created plaque/contrast attenuation ratios that were significantly different for each component. In a separate validation cohort of 47 patients, these Plaque Maps correlated significantly with VH-IVUS-determined plaque component volumes (necrotic core: r=0.41, P=0.002; fibrous plaque: r=0.54, P<0.001; calcified plaque: r=0.59, P<0.001; total plaque: r=0.62, P<0.001). We also assessed VH-IVUS and CT Plaque Maps against coregistered histology in 72 (VH-IVUS) and 87 (CT) segments from 8 postmortem coronary arteries. The diagnostic accuracy of CT to detect calcified plaque (83% versus 92%), necrotic core (80% versus 65%), and fibroatheroma (80% versus 79%) was comparable with VH-IVUS. However, although VH-IVUS could identify thin-cap fibroatheromas (TCFA) with a diagnostic accuracy of between 74% and 82% (depending on the TCFA definition used), the spatial resolution of CT prevented direct identification of TCFA.
CT-derived Plaque Maps based on contrast-adjusted attenuation ranges can define individual plaque components with a similar accuracy to VH-IVUS ex vivo. However, coronary CT Plaque Maps could not reliably classify plaques and identify TCFA, such that high-risk plaques may be misclassified or overlooked.
The role of glycoprotein IIb/IIIa inhibitors (GPI) in primary percutaneous coronary intervention (PPCI) remains uncertain. Previous analyses compare PPCI outcomes with clopidogrel plus GPI, versus ...without GPI. This does not reflect modern contemporary PPCI practice with ticagrelor or prasugrel. Nor does it answer the important question faced daily by PPCI operators: should GPI be used routinely or selectively? We aim to determine whether a strategy of routine use of GPI in contemporary PPCI practice is superior to selective GPI use. A total of 110,327 consecutive PPCIs performed in England were prospectively recorded in the British Cardiovascular Intervention Society Database (2009 to 2015). The cohort was divided into routine and selective GPI usage groups based on the PPCI operator's strategy, defined as GPI used in >75% and <25% PPCIs, respectively. Overall, GPI use declined from 73.1% to 43.3% of PPCIs. Routine compared with selective GPI usage was associated with lower all-cause 1-year mortality: 9.7% versus 11.0%, p < 0.001. There was a consistent survival benefit for routine GPI usage as compared with selective GPI usage: univariable analysis (hazard ratio = 0.88 95% confidence interval 0.83 to 0.93, p < 0.001), multivariable analysis (hazard ratio = 0.82 0.77 to 0.88, p < 0.001). For survival, there was no interaction between GPI usage and the type of P2Y12-inhibitor used. In conclusion, a strategy of routine GPI usage in patients who underwent PPCI was associated with lower all-cause mortality as compared with selective GPI usage. This benefit was maintained despite 44.3% of patients receiving prasugrel or ticagrelor.
Atherosclerotic plaques underlying most myocardial infarctions have thin fibrous caps and large necrotic cores; however, these features alone do not reliably identify plaques that rupture. Rupture ...occurs when plaque structural stress (PSS) exceeds mechanical strength. We examined whether PSS could be calculated in vivo based on virtual histology (VH) intravascular ultrasound and whether PSS varied according to plaque composition, subtype, or clinical presentation.
A total of 4429 VH intravascular ultrasound frames from 53 patients were analyzed, identifying 99 584 individual plaque components. PSS was calculated by finite element analysis in whole vessels, in individual plaques, and in higher-risk regions (plaque burden ≥70%, mean luminal area ≤4 mm(2), noncalcified VH-defined thin-cap fibroatheroma). Plaque components including total area/arc of calcification (R(2)=0.33; P<0.001 and R(2)=0.28; P<0.001) and necrotic core (R(2)=0.18; P<0.001 and R(2)=0.15; P<0.001) showed complex, nonlinear relationships with PSS. PSS was higher in noncalcified VH-defined thin-cap fibroatheroma compared with thick-cap fibroatheromas (median Q1-Q3, 8.44 6.97-10.64 versus 7.63 6.37-9.68; P=0.002). PSS was also higher in patients with an acute coronary syndrome, where mean luminal area ≤4 mm(2) (8.24 7.06-9.93 versus 7.72 6.33-9.34; P=0.03), plaque burden ≥70% (9.18 7.44-10.88 versus 7.93 6.16-9.46; P=0.02), and in noncalcified VH-defined thin-cap fibroatheroma (9.23 7.33-11.44 versus 7.65 6.45-8.62; P=0.02). Finally, PSS increased the positive predictive value for VH intravascular ultrasound to identify clinical presentation.
Finite element analysis modeling demonstrates that structural stress is highly variable within plaques, with increased PSS associated with plaque composition, subtype, and higher-risk regions in patients with acute coronary syndrome. PSS may represent a novel tool to analyze the dynamic behavior of coronary plaques with the potential to improve prediction of plaque rupture.
Features of ruptured and high-risk plaque have been described on coronary computed tomography angiography (coronary CTA), but not systematically assessed against intravascular ultrasound (IVUS). We ...examined the ability of coronary CTA to identify IVUS defined ruptured plaque and Virtual Histology Intravascular Ultrasound (VH-IVUS) defined thin-cap fibroatheroma (TCFA).
Sixty-three patients (32 with acute coronary syndrome and 31 with stable angina) underwent coronary CTA, IVUS and VH-IVUS. Plaque rupture on CTA was defined as intra-plaque contrast and its frequency compared with IVUS-defined plaque rupture. We then examined the relationship of conventional coronary CTA high-risk features (low attenuation plaque, positive remodeling, spotty calcification and the Napkin-Ring sign) in VH-IVUS-defined TCFA. We compared these with a novel index based on quantifying the ratio of necrotic core to fibrous plaque using x-ray attenuation cut-offs derived from the relationship of plaque to luminal contrast attenuation.
Of the 71 plaques interrogated with IVUS, 39 were ruptured. Coronary CTA correctly detected 13-ruptured plaques with 3 false positives giving high specificity (91%) but low sensitivity (33%). None of the conventional coronary CTA high-risk features were significantly more frequent in the higher-risk (VH-IVUS defined thin-cap) compared with thick-cap fibroatheroma. However, the new index (necrotic core/fibrous plaque ratio) was higher in thin-cap (mean 0.90) vs. thick-cap fibroatheroma (mean 0.59), p < 0.05.
Compared with intravascular ultrasound, coronary CTA identifies ruptured plaque with good specificity but poor sensitivity. We have identified a novel high-risk feature on coronary CTA (necrotic core/fibrous plaque ratio that is associated with VH-IVUS defined-TCFA.
Abstract Background Identifying vulnerable coronary plaque with coronary CT angiography is limited by overlap between attenuation of necrotic core and fibrous plaque. Using x-rays with differing ...energies alters attenuation values of these components, depending on their material composition. Objectives We sought to determine whether dual-energy CT (DECT) improves plaque component discrimination compared with single-energy CT (SECT). Methods Twenty patients underwent DECT and virtual histology intravascular ultrasound (VH-IVUS). Attenuation changes at 100 and 140 kV for each plaque component were defined, using 1088 plaque areas co-registered with VH-IVUS. Hounsfield unit thresholds that best detected necrotic core were derived for SECT (conventional attenuation values) and for DECT (using dual-energy indices, defined as difference in Hounsfield unit values at the 2 voltages/their sum). Sensitivity of SECT and DECT to detect plaque components was determined in 77 segments from 7 postmortem coronary arteries. Finally, we examined 60 plaques in vivo to determine feasibility and sensitivity of clinical DECT to detect VH-IVUS–defined necrotic core. Results In contrast to conventional SECT, mean dual-energy indices of necrotic core and fibrous tissue were significantly different with minimal overlap of ranges (necrotic core, 0.007 95% CI, –0.001 to 0.016; fibrous tissue, 0.028 95% CI, 0.016–0.050; P < .0001). DECT increased diagnostic accuracy to detect necrotic core in postmortem arteries (sensitivity, 64%; specificity, 98%) compared with SECT (sensitivity, 50%; specificity, 94%). DECT sensitivity to detect necrotic core was lower when analyzed in vivo, although still better than SECT (45% vs 39%). Conclusions DECT improves the differentiation of necrotic core and fibrous plaque in ex vivo postmortem arteries. However, much of this improvement is lost when translated to in vivo imaging because of a reduction in image quality.
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