SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: The international journal of cardiovascular imaging

28

Asymmetric septal hypertrophic cardiomyopathy (ASH) is the common phenotype of hypertrophic cardiomyopathy (HCM). We sought to classify ASH using magnetic resonance imaging (MRI) and to determine whether the MRI classification of ASH is related to the presence of risk factors for HCM. Ninety-three patients with ASH underwent cine and delayed-enhancement MRI. The ASH was classified morphologically using cine MRI at end-diastole. We evaluated the association between the MRI findings and the presence of risk factors in the ASH. The ASH was classified into three subtypes by MRI: contiguous subtype showing various clinical and MRI features (57%), sigmoid subtype (29%) with fewer risk factors, and reverse-curve subtype (14%) in younger patients with the larger myocardial mass and delayed-enhancement, which were significantly related to the risk factors. MRI was used to classify ASH into three subtypes, which might be related to the presence of risk factors.

Concepts: Nuclear magnetic resonance, Magnetic resonance imaging, Hypertrophic cardiomyopathy

28

The anatomical and functional characteristics of the left atrial appendage (LAA) and its relationships with anatomical remodeling and ischemic stroke in patients with atrial fibrillation (AF) have not been clearly established. The purpose of this study was to determine whether functional and morphological features of the LAA independently predict clinical outcome and stroke in patients with AF who underwent catheter ablation (CA). Two hundred sixty-four patients with AF, including 176 with paroxysmal AF (PAF, 54.0 ± 11.4 years old, M:F = 138:38) and 88 with persistent AF (PeAF, 56.4 ± 9.6 years old, M:F = 74:14) were studied. Of these patients, 31 (11.7 %) had a history of stroke/TIA (transient ischemic attack). The LA and LAA volumes were 124.0 ± 42.4 and 24.9 ± 4.3 ml in PeAF, these values were greater than those in PAF (81.2 ± 24.8 ml and 21.2 ± 5.1 ml, P < 0.001). The AF type (P = 0.016) and AF duration (P = 0.005), and anti-arrhythmic drugs use (P < 0.001) were significant predictors of AF recurrence after CA in all patients. Compared with patients without history of stroke, stroke patients had larger LA volume (106.9 ± 23.0 vs. 94.0 ± 38.9 ml, P = 0.004) and had lower LAA EF (50.0 ± 11.0 vs. 65.7 ± 13.4 %, P < 0.001). The independent predictors of stroke were age (P = 0.002) and LAA EF (P < 0.001) in PAF patients and that was only age (P = 0.001) in PeAF patients. In anatomical and morphological parameters of the LA and LAA, only depressed systolic function of the LAA was significantly related to stroke/TIA and recurrence of AF after CA in paroxysmal AF patients. Further large scaled prospective study is required for validation.

Concepts: Stroke, Atrial fibrillation, Transient ischemic attack, Blood pressure, Atrial flutter, Cultural studies, Left atrial appendage occlusion, Left atrial appendage

24

The American Society of Echocardiography and European Association of Echocardiography (ASE/EAE) have published an algorithm for the grading of diastolic function. However, the ability to use this algorithm effectively in daily clinical practice has not been investigated. We hypothesized that in some patients it may be difficult to grade diastolic dysfunction with this scheme, since there may be discrepancies in the assessed parameters. The aim of the current study was to test the feasibility of the ASE/EAE algorithm and to compare this with a new Thoraxcenter (TXC) algorithm. The ASE/EAE and TXC algorithms were applied to 200 patients. The ASE/EAE algorithm starts with assessment of diastolic myocardial wall velocities and left atrial (LA) volumes with subsequent assessment of E/A ratio, E-wave deceleration time and pulmonary venous flow. The TXC algorithm reverses these steps, uses LA dimension instead of volume and does not include a Valsalva manoeuvre and pulmonary venous flow. Due to inconsistencies between diastolic myocardial wall velocities and LA volumes and a not covered E/A ratio in the range of 1.5-2 it was not possible to classify 48 % of patients with the ASE/EAE algorithm, as opposed to only 10 % by the TXC algorithm. LA volume was always needed in the ASE/EAE algorithm. In only 64 % of patients LA size was necessary by the TXC algorithm. When LA volume would have been used instead of LA dimension, grading of LV diastolic function would have been different in only 2 % of patients without apparent improvement. Assessment of LA dimension was considerably faster than LA volume. The TXC algorithm to grade LV diastolic dysfunction was compared to the ASE/EAE algorithm simpler, faster, better reproducible and yields a higher diagnostic outcome.

Concepts: Cardiology, Heart, Vein, Ventricle, Acceleration, Sphere, Diastolic dysfunction, E/A ratio

23

Although more patients with congenital heart disease (CHD) are now living longer due to better surgical interventions, they require regular imaging to monitor cardiac performance. There is a need for robust clinical tools which can accurately assess cardiac function of both the left and right ventricles in these patients. We have developed methods to rapidly quantify 4D (3D + time) biventricular function from standard cardiac MRI examinations. A finite element model was interactively customized to patient images using guide-point modelling. Computational efficiency and ability to model large deformations was improved by predicting cardiac motion for the left ventricle and epicardium with a polar model. In addition, large deformations through the cycle were more accurately modeled using a Cartesian deformation penalty term. The model was fitted to user-defined guide points and image feature tracking displacements throughout the cardiac cycle. We tested the methods in 60 cases comprising a variety of congenital heart diseases and showed good correlation with the gold standard manual analysis, with acceptable inter-observer error. The algorithm was considerably faster than standard analysis and shows promise as a clinical tool for patients with CHD.

Concepts: Genetic disorder, Blood, Heart, Heart disease, Right ventricle, Ventricle, Left ventricle, Congenital heart disease

23

To investigate the clinical utility of culprit plaque characteristics and inflammatory markers for the prediction of future cardiovascular events in patients with ST-segment elevation myocardial infarction (STEMI) with successful drug-eluting stent (DES) implantation. We evaluated 172 STEMI patients with successful primary percutaneous coronary intervention (PCI) with DES using pre-PCI high-sensitivity C-reactive protein (hs-CRP), neutrophil-to-lymphocyte ratio (NLR) and pre-PCI intravascular ultrasound virtual histology (IVUS-VH) of culprit lesions. The incidence of major adverse cardiovascular events (MACE) including all-cause mortality, non-fatal MI, stroke and late revascularization were recorded during hospitalization and follow-up. During follow-up (median 41 months), the incidence of MACE did not significantly differ among patients with or without all 3 high-risk plaque features on IVUS-VH (15.1 vs. 16.2%; p = 0.39). In contrast, patients with elevated hs-CRP and NLR levels were at significant risk for MACE [32.7 vs. 5.8%; hazard ratio (HR) 7.85; p < 0.001 and 43.9 vs. 6.9%; HR 8.44; p < 0.001, respectively]. High-risk plaque features had no incremental usefulness to predict future MACE. However, the incorporation of hs-CRP and NLR into a model with conventional clinical and procedural risk factors significantly improved the C-statistic for the prediction of MACE (0.76-0.89; p = 0.04). High-risk plaque features identified by IVUS-VH in culprit lesions were not associated with future MACE in patients with STEMI receiving DES. However, elevated hs-CRP and NLR levels were significantly associated with poorer outcomes and had incremental predictive values over conventional risk factors.

Concepts: Inflammation, Myocardial infarction, Atherosclerosis, Cardiology, Percutaneous coronary intervention, Cardiovascular disease, Prediction, C-reactive protein

23

In recent years, there has been a significant effort to identify high-risk plaques in vivo prior to acute events. While number of imaging modalities have been developed to identify morphologic characteristics of high-risk plaques, prospective natural-history observational studies suggest that vulnerability is not solely dependent on plaque morphology and likely involves additional contributing mechanisms. High wall shear stress (WSS) has recently been proposed as one possible causative factor, promoting the development of high-risk plaques. High WSS has been shown to induce specific changes in endothelial cell behavior, exacerbating inflammation and stimulating progression of the atherosclerotic lipid core. In line with experimental and autopsy studies, several human studies have shown associations between high WSS and known morphological features of high-risk plaques. However, despite increasing evidence, there is still no longitudinal data linking high WSS to clinical events. As the interplay between atherosclerotic plaque, artery, and WSS is highly dynamic, large natural history studies of atherosclerosis that include WSS measurements are now warranted. This review will summarize the available clinical evidence on high WSS as a possible etiological mechanism underlying high-risk plaque development.

Concepts: Inflammation, Myocardial infarction, Atherosclerosis, Blood vessel, Atheroma, Artery, Endothelium, Force

3

Current guidelines for measuring cardiac function by tissue Doppler recommend using multiple beats, but this has a time cost for human operators. We present an open-source, vendor-independent, drag-and-drop software capable of automating the measurement process. A database of ~8000 tissue Doppler beats (48 patients) from the septal and lateral annuli were analyzed by three expert echocardiographers. We developed an intensity- and gradient-based automated algorithm to measure tissue Doppler velocities. We tested its performance against manual measurements from the expert human operators. Our algorithm showed strong agreement with expert human operators. Performance was indistinguishable from a human operator: for algorithm, mean difference and SDD from the mean of human operators' estimates 0.48 ± 1.12 cm/s (R(2) = 0.82); for the humans individually this was 0.43 ± 1.11 cm/s (R(2) = 0.84), -0.88 ± 1.12 cm/s (R(2) = 0.84) and 0.41 ± 1.30 cm/s (R(2) = 0.78). Agreement between operators and the automated algorithm was preserved when measuring at either the edge or middle of the trace. The algorithm was 10-fold quicker than manual measurements (p < 0.001). This open-source, vendor-independent, drag-and-drop software can make peak velocity measurements from pulsed wave tissue Doppler traces as accurately as human experts. This automation permits rapid, bias-resistant multi-beat analysis from spectral tissue Doppler images.

Concepts: Doppler echocardiography, Echocardiography, Measurement, Medical ultrasound, Test method, Derivative, Automation, Systems of measurement

3

In the setting of acute ST-elevation myocardial infarction (STEMI), it remains unclear which strain parameter most strongly correlates with microvascular obstruction (MVO) or intramyocardial haemorrhage (IMH). We aimed to investigate the association of MVO, IMH and convalescent left ventricular (LV) remodelling with strain parameters measured with cardiovascular magnetic resonance (CMR). Forty-three patients with reperfused STEMI and 10 age and gender matched healthy controls underwent CMR within 3-days and at 3-months following reperfused STEMI. Cine, T2-weighted, T2*-imaging and late gadolinium enhancement (LGE) imaging were performed. Infarct size, MVO and IMH were quantified. Peak global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS) and their strain rates were derived by feature tracking analysis of LV short-axis, 4-chamber and 2-chamber cines. All 43 patients and ten controls completed the baseline scan and 34 patients completed 3-month scans. In multivariate regression, GLS demonstrated the strongest association with MVO or IMH (beta = 0.53, p < 0.001). The optimal cut-off value for GLS was -13.7% for the detection of MVO or IMH (sensitivity 76% and specificity 77.8%). At follow up, 17% (n = 6) of patients had adverse LV remodeling (defined as an absolute increase of LV end-diastolic/end-systolic volumes >20%). Baseline GLS also demonstrated the strongest diagnostic performance in predicting adverse LV remodelling (AUC = 0.79; 95% CI 0.60-0.98; p = 0.03). Post-reperfused STEMI, baseline GLS was most closely associated with the presence of MVO or IMH. Baseline GLS was more strongly associated with adverse LV remodelling than other CMR parameters.

Concepts: Blood, Myocardial infarction, Atherosclerosis, Heart, Infarction, Necrosis, Ventricular fibrillation, The Strongest

2

The aim of this exploratory study was to define the Athletes Heart (AH) phenotype in Native Hawaiian & Pacific Islander (NH&PI) Rugby Football League (RFL) athletes. Specifically, (1) to describe conventional echocardiographic indices of left ventricle (LV) and right ventricle (RV) structure and function in NH&PI RFL players and matched RFL Caucasian controls (CC) and (2) to demonstrate LV and RV mechanics in these populations. Ethnicity is a contributory factor to the phenotypical expression of the AH. There are no data describing the cardiac phenotype in NH&PI athletes. Twenty-one male elite NH&PI RFL athletes were evaluated using conventional echocardiography and myocardial speckle tracking, allowing the assessment of global longitudinal strain (ε) and strain rate (SR); and basal, mid and global radial and circumferential ε and SR. Basal and apical rotation and twist were also assessed. Results were compared with age-matched Caucasian counterparts (CC; n = 21). LV mass [42 ± 9 versus 37 ± 4 g/(m2.7)], mean LV wall thickness (MWT: 9.5 ± 0.7 and 8.7 ± 0.4 mm), relative wall thickness (RWT: 0.35 ± 0.04 and 0.31 ± 0.03) and RV wall thickness (5 ± 1 and 4 ± 1 mm, all p < 0.05) were greater in NH&PI compared with CC. LV and RV cavity dimensions and standard indices of LV and RV systolic and diastolic function were similar between groups. NH&PI demonstrated reduced peak LV mid circumferential ε and early diastolic SR, as well as reduced global radial ε. There was reduced basal rotation at 25-35% systole, reduced apical rotation at 25-40% and 60-100% systole and reduced twist at 85-95% systole in NH&PI athletes. There were no differences between the two groups in RV wall mechanics. When compared to Caucasian controls, NH&PI rugby players have a greater LV mass, MWT and RWT with concomitant reductions in circumferential and twist mechanics. This data acts to prompt further research in NH&PI athletes.

Concepts: Cardiology, Heart, Blood pressure, Ventricle, Rugby league

1

Acute decompensated heart failure (ADHF) is a common reason for admission to the hospital, and readmission is frequent. Multiple factors contribute to rehospitalizations, but inadequate assessment of volume status leading to persistent congestion is an important factor. We sought to determine if focused cardiac ultrasound (FCU) of the inferior vena cava (IVC), as a surrogate of volume status, would predict readmission of ADHF patients after index hospitalization. Patients admitted with a primary diagnosis of ADHF were prospectively enrolled. All patients underwent FCU of the IVC on admission and then daily. 82 patients were enrolled. Patients demonstrated improvement in heart failure physical examination findings and symptoms during the hospitalization. There was a reduction in the size of the IVC and a significant increase in patients with small collapsible vena cava. Logistic regression analysis of physical examination, patient symptoms, and IVC parameters at discharge demonstrated IVC collapsibility and patient reported dyspnea improvement as the only significant variables to predict readmission or emergency department visit. FCU assessment of IVC size and collapsibility may be useful in patients with ADHF to predict risk of being readmitted within 30 days of hospital discharge.

Concepts: Regression analysis, Logistic regression, Patient, Hospital, Cardiology, Heart failure, Inferior vena cava, Acute decompensated heart failure