bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resting abnormalities encountered in stress echocardiography predict long-term outcomes among patients admitted for chest pain
Authors: Shekhar A , Chaudhry F , Narula J , Argulian E 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Patients hospitalized with chest pain frequently undergo stress echocardiography for detecting inducible ischemia, but other cardiac pathology is often noted on rest imaging. The long term significance of these findings is not well studied. We hypothesized that such findings indicative of cardiovascular pathology on the resting portion of a stress echocardiogram have prognostic significance for patients admitted with chest pain.

Methods
We examined patients admitted with chest pain at an academic tertiary care medical center over a 2-year period who had stress echocardiography as the primary diagnostic test. Patients admitted with heart failure symptoms or syncope or patients referred for presurgical/prerehabilitation clearance were excluded. Resting and stress echocardiograms were evaluated by cardiologists with board-certification in echocardiography, and resting abnormalities were analyzed for any effect on cardiovascular outcomes, assessed over 3 years of follow up. Survival of patients with echocardiographic abnormalities on the resting study (resting wall motion abnormalities) was compared with an age- and sex-matched cohort of admitted chest pain patients without resting abnormalities.

Results
A total of 587 patients met inclusion criteria, and 198 (34%) had resting echocardiographic abnormalities. The most common abnormality involved the left ventricle. Left ventricular hypertrophy (LVH) was seen in 16% (96), and resting wall abnormalities were seen in 15% (90); among the 90 patients with resting wall motion abnormalities, segmental wall motion abnormality was seen in 57 (9.7% of total sample), and global LV dysfunction was seen in 33 (5.6% of total sample). LVH in the absence of hypertension was found in 5% (28), raising the diagnostic possibility of hypertrophic cardiomyopathy. Moderate or greater left heart valvular abnormalities were found in 3% (18). Abnormal pericardial effusions greater than mild (excluding trivial effusion) were found in 3 patients (0.5%), and pulmonary hypertension was detected in 13 patients (2%). At 3-year follow-up, patients with resting wall motion abnormalities were found to have a higher mortality than an age and sex-matched cohort of chest pain patients without these abnormalities at rest; 85% vs. 97%, p&lt;0.015.

Conclusions
In patients hospitalized for chest pain, cardiac diagnoses with prognostic significance are often detected on the resting echocardiographic examination. These abnormalities offer insight into outcomes, given their propensity to determine mortality three years post admission, and an opportunity to institute adequate therapy that alters adverse outcomes.
Assessment of primary mitral regurgitation and lung water content using 15O-water positron emission tomography
Authors: Sigfridsson J , Harms H J , Lubberink M , Kero T , Baron T , Flachskampf F , Sorensen J 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Swedish Heart-Lung Foundation, Stockholm, Sweden.

Introduction
Severe primary mitral valve regurgitation (MR) is associated with significant hemodynamic changes in the cardio-pulmonary system, eventually resulting in lung congestion. The gold standard for assessing the regurgitation volume and fraction (RegVol; RegFraction), and severity of MR is cardiac magnetic resonance (CMR). The PET-tracer 15O-water is considered the gold standard for non-invasive quantitation of myocardial blood flow, but techniques for performing other functional assessments are evolving: using first-pass imaging total LV stroke volume (SV) can be measured with ECG-gating, and cardiac output (CO), forward SV (FSV) and pulmonary transit time (PTT) can be measured with indicator dilution techniques.

Purpose
The purpose of this study was to evaluate the method for calculating RegVol and RegFraction with 15O-water PET compared to CMR, and to assess the correlation to PWV.

Methods
N=19 patients with asymptomatic or mildly symptomatic severe MR were imaged on the same day with CMR and 15O-water PET. The PET-examinations were conducted on a digital PET/CT scanner (Discovery MI, GE Healthcare). The scans were performed in resting state and a 4-lead ECG was connected during the procedure. 400 MBq 15O-water was injected as an automated intravenous bolus simultaneous to starting a 4 min PET-emission in list mode. The list mode data was reconstructed into a 4 min dynamic series, and 16 ECG-gated images using the first 50 s of the scan only. The reconstructions were analysed using a semi-automatic software developed in-house. We calculated RegVol=total SV- FSV, RegFraction=RegVol/total SV *100 and PWV=CO*PTT. PWV was indexed against body surface area. Bland-Altman and linear regression analyses were performed and P &lt; 0.05 was considered statistically significant.

Results
PET-based RegVol and RegFraction correlated significantly with CMR (r=0.94 and 0.89, both p&lt;0.001). Bland-Altman plots showed a systematic underestimation for RegVol and RegFraction calculated by PET compared to CMR, but no proportional bias was present. PET and CMR- based RegFraction correlated significantly with PWV (r=0.70 and 0.78, both p&lt;0.001).

Conclusions
15O-water PET can be used to measure the severity of primary mitral regurgitation and the backward impact of regurgitation on lung water accumulation.
A deep learning approach for accurate and robust T1 estimation from cardiac magnetic resonance MOLLI sequences
Authors: Altur Pastor P , Ortiz-Perez J T , Doltra A , Prat S , Perea R J , Domenech B , Pujol P , Sotes S , Sitges M , Camara O , Delso G 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
T1 parametric maps of the myocardium are a recent development in cardiac Magnetic Resonance Imaging (MRI). They can be used to characterize the composition of the heart and identify alterations that can be indicative of a pathology. A common method of T1 estimation involves pixel-wise non-linear curve fitting from Modified Look-Locker Inversion Recovery (MOLLI) series [1]. Whilst relatively accurate, this method presents several drawbacks. Firstly, it assumes magnetization recovery to be a purely exponential process dependent on T1, thus neglecting other parameters such as T2 and B1 that can interfere in the process. Secondly, it does not consider that each acquisition during an inversion recovery experiment inverts the magnetization vector by a given angle and thus interferes with the recovery leading to the measurement of a shorter T1* rather than the actual T1 [2]. Additionally, since it considers each pixel individually, neglecting spatial information, it is sensitive to image quality [3]. Finally, since non-linear curve fitting is an iterative algorithm, it is computationally expensive and time-consuming.

Methods
To address these issues a convolutional neural network, DeepBLESS [4], and two spatially aware variants of it, were trained to predict T1, T2, and B1 with a dataset of MOLLI series simulated from experimental data. The simulation was performed using Bloch simulations and parameters extracted from a dataset composed of 27 single-slice MOLLI series acquired with the 5(3s)3 protocol using a b-SSFP readout at a main magnetic field strength of 3 Tesla. Thus, a dataset could be generated without relying on exponential fitting for ground truth generation.

Results
The exponential fitting of T1 was shown to consistently underestimate true T1 values by 138 +- 90 ms. In comparison, the spatially naïve DeepBLESS approach showed a mean absolute error of 14 +- 9 ms and the spatially aware DeepBLESS approach (Median-DeepBLESS) showed a mean absolute error of 13 +- 9 ms. As can be seen in Figure 1, Median-DeepBLESS also showed considerably more resilience to noise than exponential fitting and the spatially naïve version of DeepBLESS. Additionally, the deep learning approaches showcased promising results with regards to the estimation of T2 and B1 from MOLLI sequences (See Figure 2).

Conclusions
It was shown that the Deep Learning approaches eliminated the underestimation bias of exponential fitting with the spatially aware network Median-DeepBLESS being more robust to noise than both exponential fitting and the standard DeepBLESS network for myocardial T1 estimation. Relatively accurate estimation of T2 and B1 from MOLLI sequences was also accomplished through the Deep Learning approach, which may lead to simultaneous T1, T2, and B1 estimation in common clinical practice in the future.
Assessment of the left ventricular longitudinal deformation failed to detect early changes after the second-stage percutaneous coronary intervention in patients with the acute coronary syndrome
Authors: Dankowski R , Leszniewski M , Lesiak M , Sacharczuk W , Kalmucki P , Ozegowski S , Szyszka A 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Primary intervention in acute coronary syndrome (ACS) is often followed by the second-stage procedure when other atherosclerotic lesions are present. However, there is no data regarding the early effects of such a strategy on left ventricular function. Speckle-tracking echocardiography has been proven a sensitive method in assessing myocardial function.

Purpose
The study aimed to assess the early results of the second stage of percutaneous coronary intervention (PCI) in patients with ACS.

Methods
The study group consisted of 61 patients aged from 47 to 92 (mean age 66,3± 9,8) years, 21 women (34,4%) and 40 men (65,6%) who had ACS. Primary treatment involved culprit-lesion only. All pts were optimally treated regarding ischemic heart disease. The second-stage PCI was performed up to four months after ACS. Patients underwent transthoracic echocardiography 48 hours before and after the second-stage PCI. Using automated functional imaging (AFI), we analyzed the global longitudinal strain (GLS) of the left ventricle, GLS in the four-chamber view (GLS-4CH), the two-chamber view (GLS-2CH), and the three-chamber view (GLS-3CH). We also assessed the mean of the peak longitudinal strain of the myocardial segments according to the standard assignment to coronary artery territories, i.e. left anterior descending (LAD), right coronary artery (RCA) and circumflex coronary artery (LCX).

Results
The following second-stage PCI were performed in the study group: 33 procedures regarding the left anterior descending artery, 15 procedures regarding the left circumflex artery and 13 procedures regarding the right coronary artery. The mean value of the GLS of the left ventricle before the second-stage PCI was slightly reduced compared to the currently established norm (GLS= −16.7%). The second-stage PCI did not result in early changes in the GLS. We also did not observe any significant changes in the mean peak longitudinal strain according to the coronary artery territories (Table 1).

Conclusions
Despite the proven sensitivity of the deformation imaging technique in assessing left ventricular function, the present work does not show an early effect of the percutaneous coronary intervention on either the global longitudinal strain of the left ventricle or the longitudinal strain of the segments allocated to each coronary arterial territory.
Long postcovid injury on left ventricle function
Authors: Tselov N , Hristova K , Marinov R , Zlatancheva G , Velikov T 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.
Post COVID19 condition occurs in individuals with a history of probable or confirmed SARS Cov2 infection, usually 3 months from the onset of COVID19 with symptoms that last for up to at least 2 months and cannot be explained by an alternative diagnosis.
Common symptoms include fatigue, shortness of breath, cognitive dysfunction, but also arterial hypertension and generally have an impact on everyday function. Symptoms may be new onset following initial recovery from an acute COVID 19 episode or persist from the initial illness.

Aim
COVID 19 pneumonia initiates new onset arterial hypertension (AH) and aggravates the structural and functional myocardium remodeling in the long term after hospitalization.

Methods
The study population /initially questioned 1500 patients for symptoms after acute COVID 19 pneumonia / included 220 patients without history of any disease, mean age of 45±12 years, male 145 (43±10 years) female 75 ( 52± 14 years).We used Speckle tracking echocardiography to analyze the global longitudinal strain (GLS).
GLS was extracted by 3, 4 and 2 chamber apical view images on 70 fr/s for left ventricle ( LV ) and right ventricle( RV ).CMR with LGE was performed at 3rd (3mFU) and 12th months (12mFU) also to confirm our resulst.
AMBP analysis, MAP and HR were performed at baseline /30–40 days after acute infection/ 3rd and 12th months follow up.

Results
From initial population /1500 pts/ self-reported symptoms at 12mFU are 1265 ( 84.6 % ) and 235 (15.4 % ) are symptom free at 12mFU. AH presence at 3mFU in 143( 65% of patients )up to 161 patients (73% at 12mFU).
Symptoms of heart failure with preserved EF were found at 3mFU in 91 pts (41%) and in 99 pts (45%) at 12mFU
Despite normal EF, GLS / minus 18.5 %, p&lt;0.01) and segmental LS in all apical and mid anteroseptal, inferoseptal and basal anteroseptal and inferoseptal levels ( minus 16% to minus 18%, p &lt;0.01) and RV ( 22.3% to 24%) at 12mFU shown diminished and still preserved values, even in 3 level layers. Performed CMR confirmed injured segments.

Conlusions
New onset AH is one of major symptoms after COVID 19 and remains at 12mFU. Despite of satisfactory improvement of conventional parameters for LV and RV function, GLS indicate worsening of the LV systolic function. In pts with COVID-19 pneumonia echocardiography showed predominantly decrease of the load on the right heart at 3mFU. LV function showed slightly improvement at 12mFU.
Impact of left coronary artery bifurcation angle on computed tomography derived fractional flow reserve in normal coronary artery disease
Authors: Tsugu T , Tanaka K , Nagatomo Y , Belsack D , Devos H , Buls N , Cosyns B , Argacha J F , De Maeseneer M , De Mey J 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Computed-tomography (CT) derived fractional-flow-reserve (FFRCT) decreases from the proximal to the distal part of vessel due to the influence of various factors. The energy loss due to the bifurcation angle may potentially contribute to a progressive FFRCT decline. However, the association of the bifurcation angle with FFRCT is still not entirely understood.

Purpose
This study aimed to investigate the impact of various bifurcation angles on FFRCT decline below the clinically crucial pathological value of 0.80 in normal coronary arteries.

Methods
A total of 83 consecutive patients who underwent both CT angiography including FFRCT and invasive coronary angiography, resulting in normal coronary arteries were evaluated. ΔFFRCT was defined as the magnitude of the change in FFRCT from the proximal to the distal vessel in the left anterior descending (LAD) and left circumflex (LCX). Both LAD angle and LCX bifurcation angle were measured as the crossing angle between the centrelines of the left main trunk and each coronary artery (LAD or LCX) on the 3-dimensional volume rendered image of the coronary artery tree (Figure 1). Vessel length, lumen volume, non-calcified plaque volume, and calcified plaque volume were assessed.

Results
Bifurcation angle was significantly lower in LAD angle (LAD angle, 31.1 ± 6.6°; LCX angle, 42.8 ± 14.9°, p &lt; 0.0001). FFRCT showed a continuous gradual decline from the proximal to the distal in both LAD (from 0.95 ± 0.03 to 0.81 ± 0.06) and LCX (from 0.96 ± 0.03 to 0.88 ± 0.06). ΔFFRCT was significantly greater in LAD angle (LAD angle, 0.13 ± 0.06; LCX angle, 0.08 ± 0.05, p &lt; 0.0001) ΔFFRCT was significantly correlated with each bifurcation angle (LAD angle, r = 0.35, p = 0.001; LCX angle, r = 0.26, p = 0.02) and vessel length (LAD angle, r = 0.30, p = 0.005; LCX angle, r = 0.49, p &lt; 0.0001) (Figure 2A). In LAD, vessel length was the strongest predictor for distal FFRCT of ≤ 0.80 (β-coefficient = 0.56, p = 0.0002), immediately followed by the bifurcation angle (β-coefficient = 0.24, p = 0.02). The bifurcation angle was a good predictor for a distal FFRCT ≤ 0.80 (LAD angle, cut-off 31.0°, AUC 0.70, 95% CI 0.58–0.83, sensitivity 74%, specificity 68%; LCX angle, cut-off 52.6°, AUC 0.86, 95% CI 0.76–0.96, sensitivity 88%, specificity 85%) (Figure 2B).

Conclusions
The change in FFRCT depended on the bifurcation angle. In normal coronary arteries, vessel length was the most influential factor on FFRCT, immediately followed by the bifurcation angle.
The role transmural strain gradient in assessment of functionally single ventricle contractility
Authors: Kowalczyk M , Kordybach-Prokopiuk M , Kowalski M , Hoffman P 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The funds of the Ministry of Education and Science.

Background
Cardiac imaging in patients with FSV (functionally single ventricle) underwent the Fontan procedure is a challenge. One of the most difficult issue to be resolved in FSV patients is myocardial contractility. Thus, we sought for deformation parameters analysis by STE (Speckle Tracing Echocardiography), for haemodynamic and structural reason. We incorporated a novel STE (Speckle Tracing Echocardiography) parameter– TG (transmural strain gradient) representing the difference in strain between subendocardial and subepicardial layer to assess FSV contractile reserve. The role of TG in assessment of FSV after Fontan palliation has not been evaluated yet.

Purpose
The study aimed to introduce/evaluate transmural longitudinal strain gradient (TG) at rest and during exercise as marker of FSV contractility and exercise performace.

Methods
The group of 37 patients with FSV after Fontan palliation were enrolled in our study at least 12 months after Fontan operation and in sinus rhythm on ECG. We performed an transthoracic echocardiography at rest and during exercise on a semi-supine cycle ergometer. The apical-chamber views were registered for subsequent post-processing analysis. Due to heterogeneous FSV morphology and primary defects as well as accompanying intraventricular septum segments malformation in majority of cases, we decided to measure and analyse FSV free wall longitudinal strain only. The values of layer-specific: subendocardial and subepicardial longitudinal free wall systolic strain were assessed and the gradient between them was calculated. The TG at rest and during exercise were compared with the cardiopulmonary exercise test results, NYHA class, FSV systolic function studied by CMR (Cardiac Magnetic Resonance) and NT-proBNP concentration.

Results
The values of TG at rest and during exercise correlated with peak oxygen uptake during the cardio-pulmonary exercise test (p = ,012 for TG at rest, p = ,031). TG during exercise was negatively correlated with CMR-derived ejection fraction (p = ,031) . There was no relationship between TG and NYHA-class and NT-proBNP.

Conclusion(s)
TG is a promising parameter for FSV contractility assessment. Our preliminary study suggests that it can complete traditional imaging technics and derived parameters. TG is highly associated to exercise capacity. However, utility of TG requires further investigation.
(p)ppGpp and moonlighting RNases influence the first step of lipopolysaccharide biosynthesis in Escherichia coli
Authors: Brückner Simon , Müller Fabian , Schadowski Laura , Kalle Tyll , Weber Sophia , Marino Emily C , Kutscher Blanka , Möller Anna-Maria , Adler Sabine , Begerow Dominik , Steinchen Wieland , Bange Gert , Narberhaus Franz 
Published: June 2023

Abstract
The outer membrane (OM) protects Gram-negative bacteria from harsh environmental conditions and provides intrinsic resistance to many antimicrobial compounds. The asymmetric OM is characterized by phospholipids in the inner leaflet and lipopolysaccharides (LPS) in the outer leaflet. Previous reports suggested an involvement of the signaling nucleotide ppGpp in cell envelope homeostasis in Escherichia coli. Here, we investigated the effect of ppGpp on OM biosynthesis. We found that ppGpp inhibits the activity of LpxA, the first enzyme of LPS biosynthesis, in a fluorometric in vitro assay. Moreover, overproduction of LpxA resulted in elongated cells and shedding of outer membrane vesicles (OMVs) with altered LPS content. These effects were markedly stronger in a ppGpp-deficient background. We further show that RnhB, an RNase H isoenzyme, binds ppGpp, interacts with LpxA, and modulates its activity. Overall, our study uncovered new regulatory players in the early steps of LPS biosynthesis, an essential process with many implications in the physiology and susceptibility to antibiotics of Gram-negative commensals and pathogens.
Hot Instantaneous Temperature and Affect: Meaningful Activities as a Buffer for Older Adults With Low Socioeconomic Status
Authors: Lin Zhixuan , Chin David C W , Fung Helene H , Lay Jennifer C , Tse Dwight C K 
Published: June 2023

Abstract

Background and Objectives
Extremely hot temperature affects psychological well-being negatively, especially for older adults with lower socioeconomic status (SES). The objectives of this study are to examine: (a) the impact of hot instantaneous temperature on older adults’ emotional well-being and (b) whether meaningful engagement could reduce the above impact, particularly for those of lower SES.

Research Design and Methods
We conducted a quantitative time-sampling study during hot-weather months (May–September) in 2021 and 2022. The sample comprises 344 participants aged 60 years or older (Mage = 67.15, SDage = 5.26) living in urban areas of Hong Kong, where hot days (daily maximum temperature ≥33°C) accounted for 23% of the study days. Participants reported positive and negative affect, and engagement in meaningful activities, three times a day over a 10-day period, and wore sensors that tracked the instantaneous temperature of their immediate environment. Multilevel modeling was employed to examine the impacts on affect from temperature, SES, and meaningful activity engagement.

Results
Hotter instantaneous temperature predicted greater momentary negative affect and less positive affect immediately afterwards. Meaningful engagement significantly buffered against the affective impacts of hotter temperature, and this buffering effect was more salient among older adults of lower SES.

Discussion and implications
This study highlights the role of meaningful engagement in reducing the impact of hotter instantaneous temperature on older adults’ emotional well-being, particularly for those of lower SES. Meaningful activity engagement may be capitalized on, as a strategy, to reduce climate-related social inequality.