Time-encoded ASL reveals lower cerebral blood flow in the early AD continuum.

INTRODUCTION: Cerebral blood flow (CBF) is reduced in cognitively impaired (CI) Alzheimer's disease (AD) patients. We checked the sensitivity of time-encoded arterial spin labeling (te-ASL) in measuring CBF alterations in individuals with positive AD biomarkers and associations with relevant biomarkers in cognitively unimpaired (CU) individuals. METHODS: We compared te-ASL with single-postlabel delay (PLD) ASL in measuring CBF in 59 adults across the AD continuum, classified as CU amyloid beta (Aß) negative (-), CU Aß positive (+), and CI Aß+. We sought associations of CBF with biomarkers of AD, cerebrovascular disease, synaptic dysfunction, neurodegeneration, and cognition in CU participants. RESULTS: te-ASL was more sensitive at detecting CBF reduction in the CU Aß+ and CI Aß+ groups. In CU participants, lower CBF was associated with altered biomarkers of Aß, tau, synaptic dysfunction, and neurodegeneration. DISCUSSION: CBF reduction occurs early in the AD continuum. te-ASL is more sensitive than single-PLD ASL at detecting CBF changes in AD. HIGHLIGHTS: Lower CBF can be detected in CU subjects in the early AD continuum. te-ASL is more sensitive than single-PLD ASL at detecting CBF alterations in AD. CBF is linked to biomarkers of AD, synaptic dysfunction, and neurodegeneration.

Adolescent Reference Values for MR-Derived Biventricular Strain Obtained Using Feature-Tracking and Myocardial Tagging.

BACKGROUND: Myocardial strain is a promising marker for the detection of early left or right ventricular (LV or RV) dysfunction in pediatric populations. The reference standard for MR strain measurement is myocardial tagging (MT); however, MT has limited clinical utility because the additional acquisitions needed are time-consuming. In contrast, MR-feature tracking (FT) allows strain quantification from routinely acquired cine sequences. Studies providing reference values obtained with both FT and MT for adolescents are lacking. PURPOSE: To use MR-FT and MT to define sex-specific LV and RV strain reference values for adolescents. STUDY TYPE: Cross-sectional, prospective. POPULATION: One hundred twenty-three adolescents aged 15-18 years (52% girls) without known cardiovascular disease. FIELD STRENGTH/SEQUENCE: Balanced steady-state free-precession sequence for FT analysis and a spatial modulation of magnetization hybrid TFE-EPI sequence for MT acquisitions at 3.0-T. ASSESSMENT: Segment Medviso software was used to obtain longitudinal (LS) and circumferential (CS) strain for both ventricles, and radial strain (RS) for LV. STATISTICAL TESTS: The Student t-test was used for between-sex comparisons of continuous variables. Sex-specific percentiles were calculated using the weighted average method. Intraobserver and interobserver agreement was assessed in 30 randomly selected studies using intraclass correlation coefficients (ICC). A P-value <0.05 was considered statistically significant. RESULTS: FT-derived LVLS and LVCS were significantly higher in girls than in boys (-19.8% vs. -17.8% and -22.2% vs. -21.0%, respectively), as they were with MT (LVLS: -18.1% vs. -16.8%; LVCS: -20.8% vs. -19.7%). FT-LVRS was higher in girls than in boys (44.8% vs. 35.1%), while MT-LVRS was the opposite (18.6% vs. 22.7%). FT-RVLS was higher in girls (-23.4% vs. -21.3%), but there were no between-sex differences in MT-derived RVLS or RVCS. ICC values for intraobserver agreement were ≥0.89, whereas for interobserver agreement were <0.80 for MT-LVRS and ≥0.80 for all remaining parameters. DATA CONCLUSION: This study provides sex-specific reference biventricular strain values obtained with MR-MT and MR-FT for adolescents aged 15-18 years. MR-FT may be a valid method for obtaining strain values in pediatric populations. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.

Association between subclinical atherosclerosis burden and unrecognized myocardial infarction detected by cardiac magnetic resonance in middle-aged low-risk adults.

AIMS: Evidence on the association between subclinical atherosclerosis (SA) and cardiovascular (CV) events in low-risk populations is scant. To study the association between SA burden and an ischaemic scar (IS), identified by cardiac magnetic resonance (CMR), as a surrogate of CV endpoint, in a low-risk population. METHODS AND RESULTS: A cohort of 712 asymptomatic middle-aged individuals from the Progression of Early SA (PESA-CNIC-Santander) study (median age 51 years, 84% male, median SCORE2 3.37) were evaluated on enrolment and at 3-year follow-up with 2D/3D vascular ultrasound (VUS) and coronary artery calcification scoring (CACS). A cardiac magnetic study (CMR) was subsequently performed and IS defined as the presence of subendocardial or transmural late gadolinium enhancement (LGE). On CMR, 132 (19.1%) participants had positive LGE, and IS was identified in 20 (2.9%) participants. Individuals with IS had significantly higher SCORE2 at baseline and higher CACS and peripheral SA burden (number of plaques by 2DVUS and plaque volume by 3DVUS) at both SA evaluations. High CACS and peripheral SA (number of plaques) burden were independently associated with the presence of IS, after adjusting for SCORE2 [OR for 3rd tertile, 8.31; 95% confidence interval (CI) 2.85-24.2; P < 0.001; and 2.77; 95% CI, 1.02-7.51; P = 0.045, respectively] and provided significant incremental diagnostic value over SCORE2. CONCLUSION: In a low-risk middle-aged population, SA burden (CAC and peripheral plaques) was independently associated with a higher prevalence of IS identified by CMR. These findings reinforce the value of SA evaluation to early implement preventive measures. CLINICAL TRIAL REGISTRATION: Progression of Early Subclinical Atherosclerosis (PESA) Study Identifier: NCT01410318.

Metabolic changes contribute to maladaptive right ventricular hypertrophy in pulmonary hypertension beyond pressure overload: an integrative imaging and omics investigation.

Right ventricular (RV) failure remains the strongest determinant of survival in pulmonary hypertension (PH). We aimed to identify relevant mechanisms, beyond pressure overload, associated with maladaptive RV hypertrophy in PH. To separate the effect of pressure overload from other potential mechanisms, we developed in pigs two experimental models of PH (M1, by pulmonary vein banding and M2, by aorto-pulmonary shunting) and compared them with a model of pure pressure overload (M3, pulmonary artery banding) and a sham-operated group. Animals were assessed at 1 and 8 months by right heart catheterization, cardiac magnetic resonance and blood sampling, and myocardial tissue was analyzed. Plasma unbiased proteomic and metabolomic data were compared among groups and integrated by an interaction network analysis. A total of 33 pigs completed follow-up (M1, n = 8; M2, n = 6; M3, n = 10; and M0, n = 9). M1 and M2 animals developed PH and reduced RV systolic function, whereas animals in M3 showed increased RV systolic pressure but maintained normal function. Significant plasma arginine and histidine deficiency and complement system activation were observed in both PH models (M1&M2), with additional alterations to taurine and purine pathways in M2. Changes in lipid metabolism were very remarkable, particularly the elevation of free fatty acids in M2. In the integrative analysis, arginine-histidine-purines deficiency, complement activation, and fatty acid accumulation were significantly associated with maladaptive RV hypertrophy. Our study integrating imaging and omics in large-animal experimental models demonstrates that, beyond pressure overload, metabolic alterations play a relevant role in RV dysfunction in PH.

Absence of Myocardial Involvement After SARS-CoV-2 Vaccination in Asymptomatic Adolescents.

This study aimed to evaluate the presence of subclinical myocardial damage in adolescents who were vaccinated against SARS-CoV-2. One hundred twenty asymptomatic adolescents with a mean age of 16.0 ± 0.4 years (51% girls) underwent cardiac magnetic resonance (CMR) imaging. SARS-CoV-2 IgG/IgM antibody testing was performed, and self-reported dates of confirmed SARS-CoV-2 infection and/or vaccination were collected. Participants were classified according to SARS-CoV-2 status as naïve (non-infected and unvaccinated, n = 74), infected (unvaccinated, n = 23), and vaccinated (independently of past infection status, n = 23). Biventricular volumes and ejection fraction and myocardial T2 relaxation time were similar in the three groups. T1 relaxation time was slightly higher in vaccinated adolescents (1249 ± 35 ms) than in naïve and infected participants (1231 ± 30 ms and 1227 ± 29 ms, respectively; p = 0.035), although this difference was considered clinically irrelevant. This observational study found no evidence of relevant subclinical myocardial involvement after SARS-CoV-2 vaccination in asymptomatic adolescents.

Determinants of Progression and Regression of Subclinical Atherosclerosis Over 6 Years.

BACKGROUND: Atherosclerosis is a systemic disease that frequently begins early in life. However, knowledge about the temporal disease dynamics (ie, progression or regression) of human subclinical atherosclerosis and their determinants is scarce. OBJECTIVES: This study sought to investigate early subclinical atherosclerosis disease dynamics within a cohort of middle-aged, asymptomatic individuals by using multiterritorial 3-dimensional vascular ultrasound (3DVUS) imaging. METHODS: A total of 3,471 participants from the PESA (Progression of Early Subclinical Atherosclerosis) cohort study (baseline age 40-55 years; 36% female) underwent 3 serial 3DVUS imaging assessments of peripheral arteries at 3-year intervals. Subclinical atherosclerosis was quantified as global plaque volume (mm3) (bilateral carotid and femoral plaque burden). Multivariable logistic regression models for progression and regression were developed using stepwise forward variable selection. RESULTS: Baseline to 6-year subclinical atherosclerosis progression occurred in 32.7% of the cohort (17.5% presenting with incident disease and 15.2% progressing from prevalent disease at enrollment). Regression was observed in 8.0% of those patients with baseline disease. The effects of higher low-density lipoprotein cholesterol (LDL-C) and elevated systolic blood pressure (SBP) on 6-year subclinical atherosclerosis progression risk were more pronounced among participants in the youngest age stratum (Pinteraction = 0.04 and 0.02, respectively). CONCLUSIONS: Over 6 years, subclinical atherosclerosis progressed in one-third of middle-age asymptomatic subjects. Atherosclerosis regression is possible in early stages of the disease. The impact of LDL-C and SBP on subclinical atherosclerosis progression was more pronounced in younger participants, a finding suggesting that the prevention of atherosclerosis and its progression could be enhanced by tighter risk factor control at younger ages, with a likely long-term impact on reducing the risk of clinical events. (Progression of Early Subclinical Atherosclerosis [PESA; also PESA-CNIC-Santander]; NCT01410318).

Longitudinal interplay between subclinical atherosclerosis, cardiovascular risk factors, and cerebral glucose metabolism in midlife: results from the PESA prospective cohort study.

BACKGROUND: Cardiovascular disease and dementia often coexist at advanced stages. Yet, longitudinal studies examining the interplay between atherosclerosis and its risk factors on brain health in midlife are scarce. We aimed to characterise the longitudinal associations between cerebral glucose metabolism, subclinical atherosclerosis, and cardiovascular risk factors in middle-aged asymptomatic individuals. METHODS: The Progression of Early Subclinical Atherosclerosis (PESA) study is a Spanish longitudinal observational cohort study of 4184 asymptomatic individuals aged 40-54 years (NCT01410318). Participants with subclinical atherosclerosis underwent longitudinal cerebral [18F]fluorodeoxyglucose ([18F]FDG)-PET, and annual percentage change in [18F]FDG uptake was assessed (primary outcome). Cardiovascular risk was quantified with SCORE2 and subclinical atherosclerosis with three-dimensional vascular ultrasound (exposures). Multivariate regression and linear mixed effects models were used to assess associations between outcomes and exposures. Additionally, blood-based biomarkers of neuropathology were quantified and mediation analyses were performed. Secondary analyses were corrected for multiple comparisons using the false discovery rate (FDR) approach. FINDINGS: This longitudinal study included a PESA subcohort of 370 participants (median age at baseline 49·8 years [IQR 46·1-52·2]; 309 [84%] men, 61 [16%] women; median follow-up 4·7 years [IQR 4·2-5·2]). Baseline scans took place between March 6, 2013, and Jan 21, 2015, and follow-up scans between Nov 24, 2017, and Aug 7, 2019. Persistent high risk of cardiovascular disease was associated with an accelerated decline of cortical [18F]FDG uptake compared with low risk (ß=-0·008 [95% CI -0·013 to -0·002]; pFDR=0·040), with plasma neurofilament light chain, a marker of neurodegeneration, mediating this association by 20% (ß=0·198 [0·008 to 0·740]; pFDR=0·050). Moreover, progression of subclinical carotid atherosclerosis was associated with an additional decline in [18F]FDG uptake in Alzheimer's disease brain regions, not explained by cardiovascular risk (ß=-0·269 [95% CI -0·509 to -0·027]; p=0·029). INTERPRETATION: Middle-aged asymptomatic individuals with persistent high risk of cardiovascular disease and subclinical carotid atherosclerosis already present brain metabolic decline, suggesting that maintenance of cardiovascular health during midlife could contribute to reductions in neurodegenerative disease burden later in life. FUNDING: Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III, Santander Bank, Pro-CNIC Foundation, BrightFocus Foundation, BBVA Foundation, "la Caixa" Foundation.

Cardiac Insulin Resistance in Subjects With Metabolic Syndrome Traits and Early Subclinical Atherosclerosis.

OBJECTIVE: Experimental evidence suggests that metabolic syndrome (MetS) is associated with changes in cardiac metabolism. Whether this association occurs in humans is unknown. RESEARCH DESIGN AND METHODS: 821 asymptomatic individuals from the Progression of Early Subclinical Atherosclerosis (PESA) study (50.6 [46.9-53.6] years, 83.7% male) underwent two whole-body 18F-fluorodeoxyglucose positron emission tomography-magnetic resonance (18F-FDG PET-MR) 4.8 ± 0.6 years apart. Presence of myocardial 18F-FDG uptake was evaluated qualitatively and quantitatively. No myocardial uptake was grade 0, while positive uptake was classified in grades 1-3 according to target-to-background ratio tertiles. RESULTS: One hundred fifty-six participants (19.0%) showed no myocardial 18F-FDG uptake, and this was significantly associated with higher prevalence of MetS (29.0% vs. 13.9%, P < 0.001), hypertension (29.0% vs. 18.0%, P = 0.002), and diabetes (11.0% vs. 3.2%, P < 0.001), and with higher insulin resistance index (HOMA-IR, 1.64% vs. 1.23%, P < 0.001). Absence of myocardial uptake was associated with higher prevalence of early atherosclerosis (i.e., arterial 18F-FDG uptake, P = 0.004). On follow-up, the associations between myocardial 18F-FDG uptake and risk factors were replicated, and MetS was more frequent in the group without myocardial uptake. The increase in HOMA-IR was associated with a progressive decrease in myocardial uptake (P < 0.001). In 82% of subjects, the categorization according to presence/absence of myocardial 18F-FDG uptake did not change between baseline and follow-up. MetS regression on follow-up was associated with a significant (P < 0.001) increase in myocardial uptake. CONCLUSIONS: Apparently healthy individuals without cardiac 18F-FDG uptake have higher HOMA-IR and higher prevalence of MetS traits, cardiovascular risk factors, and early atherosclerosis. An improvement in cardiometabolic profile is associated with the recovery of myocardial 18F-FDG uptake at follow-up.

Non-invasive electromechanical assessment during atrial fibrillation identifies underlying atrial myopathy alterations with early prognostic value.

Electromechanical characterization during atrial fibrillation (AF) remains a significant gap in the understanding of AF-related atrial myopathy. This study reports mechanistic insights into the electromechanical remodeling process associated with AF progression and further demonstrates its prognostic value in the clinic. In pigs, sequential electromechanical assessment during AF progression shows a progressive decrease in mechanical activity and early dissociation from its electrical counterpart. Atrial tissue samples from animals with AF reveal an abnormal increase in cardiomyocytes death and alterations in calcium handling proteins. High-throughput quantitative proteomics and immunoblotting analyses at different stages of AF progression identify downregulation of contractile proteins and progressive increase in atrial fibrosis. Moreover, advanced optical mapping techniques, applied to whole heart preparations during AF, demonstrate that AF-related remodeling decreases the frequency threshold for dissociation between transmembrane voltage signals and intracellular calcium transients compared to healthy controls. Single cell simulations of human atrial cardiomyocytes also confirm the experimental results. In patients, non-invasive assessment of the atrial electromechanical relationship further demonstrate that atrial electromechanical dissociation is an early prognostic indicator for acute and long-term rhythm control.

Ensayo clínico multicéntrico para la resección de pólipos rectales mediante un nuevo dispositivo de acceso transanal híbrido laparoendoscópico / Multicenter clinical trial for the resection of rectal polyps using a new laparoendoscopic hybrid transanal access device

Introducción: Los pólipos complejos requieren el uso de técnicas endoscópicas avanzadas o la cirugía mínimamente invasiva para su abordaje. En los pólipos rectales es de especial relevancia llegar a un consenso de cuál es el mejor abordaje de estos para evitar infratratamientos o sobretratamientos que incrementen una morbimortalidad innecesaria. Métodos: Se describe un ensayo clínico piloto con un producto sanitario de primer uso en humanos multicéntrico y prospectivo. Se plantea la hipótesis que UNI-VEC® facilita la cirugía laparoendoscópica transanal para la extirpación de tumores rectales precoces. El objetivo principal es evaluar que es seguro y cumple los requisitos funcionales establecidos. Los secundarios son evaluar resultados, complicaciones y nivel de satisfacción.Resultados: Se reclutaron 16 pacientes en 12 meses con un seguimiento mínimo de dos meses. El tamaño medio ha sido de 3,4 cm, siendo el pólipo mayor de 6 cm. Respecto a la localización, la media se encontraba a 6,6 cm del margen anal. Se realizó resección endoscópica mucosa (REM) (6,3%), disección submucosa endoscópica (DSE) (43,8%), resección espesor completo (REC) (6,3%) y transanal minimally invasive surgery (TAMIS) (43,8%). El tiempo medio fueron 73,25 min; 56,3% utiliza una cámara de 30̊ y 43,8% el endoscopio flexible como instrumento de visión. El 56,3% son lesiones benignas y 43,8% malignas. En 87,5% se consigue resección completa. En cuanto a las complicaciones, se presenta sangrado leve (Clavien I) en 25, 6,3 y 21,4% a las 24 h, 48 h y siete días, respectivamente. La continencia se valora según la Escala de Wexner. A los siete días, 60% presentan continencia perfecta, 26,7% IF leve y 13,3% IF moderada. A los 30 días, 66,7% continencia perfecta, 20% IF leve y 13,3% IF moderada. A los dos meses se revisan cuatro de los pacientes que a los 30 días presentaban un Wexner superior al preoperatorio y se demuestra continencia perfecta en 25% de los pacientes, 50% leve y 25% moderada. (AU)

Introduction: Complex polyps require the use of advanced endoscopic techniques or minimally invasive surgery for their approach. In rectal polyps it is of special relevance to reach a consensus on the best approach to avoid under- or overtreatment that increases unnecessary morbidity and mortality. Methods: We describe a prospective, multicenter, pilot clinical trial with a first-in-human medical device. It is hypothesized that UNI-VEC® facilitates transanal laparoendoscopic surgery for the removal of early rectal tumors. The primary objective is to evaluate that it is safe and meets the established functional requirements. Secondary objectives are to evaluate results, complications and level of satisfaction. Results: Sixteen patients were recruited in 12 months with a minimum follow-up of 2 months. The mean size was 3.4 cm with the largest polyp being 6 cm. Regarding location, the mean was 6.6 cm from the anal margin. Endoscopic mucosal resection (EMR) (6.3%), endoscopic submucosal dissection (ESD) (43.8%), REC (6.3%) and TAMIS (43.8%) were performed. The mean time was 73.25 min. The 56.3% used a 30° camera and 43.8% used the flexible endoscope as a viewing instrument. The 56.3% were benign lesions and 43.8% malignant. Complete resection is achieved in 87.5%. Regarding complications, mild bleeding (Clavien I) occurred in 25%, 6.3% and 21.4% at 24 h, 48 h and 7 days, respectively. Continence was assessed according to the Wexner scale. At 7 days, 60% showed perfect continence, 26.7% mild FI and 13.3% moderate FI. At 30 days, 66.7% had perfect continence, 20% mild FI and 13.3% moderate FI. At 2 months, 4 patients were reviewed who at 30 days had a Wexner's degree higher than preoperative and perfect continence was demonstrated in 25% of the patients, 50% mild and 25% moderate. (AU)

Magnetic resonance imaging reference values for cardiac morphology, function and tissue composition in adolescents.

Background: Cardiovascular magnetic resonance (CMR) is a precise tool for the assessment of cardiac anatomy, function, and tissue composition. However, studies providing CMR reference values in adolescence are scarce. We aim to provide sex-specific CMR reference values for biventricular and atrial dimensions and function and myocardial relaxation times in this population. Methods: Adolescents aged 15-18 years with no known cardiovascular disease underwent a non-contrast 3-T CMR scan between March 2021 and October 2021. The imaging protocol included a cine steady-state free-precession sequence for the analysis of chamber size and function, as well as T2-GraSE and native MOLLI T1-mapping for the characterization of myocardial tissue. Findings: CMR scans were performed in 123 adolescents (mean age 16 ± 0.5 years, 52% girls). Mean left and right ventricular end-diastolic indexed volumes were higher in boys than in girls (91.7 ± 11.6 vs 78.1 ± 8.3 ml/m2, p < 0.001; and 101.3 ± 14.1 vs 84.1 ± 10.5 ml/m2, p < 0.001), as was the indexed left ventricular mass (48.5 ± 9.6 vs 36.6 ± 6.0 g/m2, p < 0.001). Left ventricular ejection fraction showed no significant difference by sex (62.2 ± 4.1 vs 62.8 ± 4.2%, p = 0.412), whereas right ventricular ejection fraction trended slightly lower in boys (55.4 ± 4.7 vs. 56.8 ± 4.4%, p = 0.085). Indexed atrial size and function parameters did not differ significantly between sexes. Global myocardial native T1 relaxation time was lower in boys than in girls (1215 ± 23 vs 1252 ± 28 ms, p < 0.001), whereas global myocardial T2 relaxation time did not differ by sex (44.4 ± 2.0 vs 44.1 ± 2.4 ms, p = 0.384). Sex-stratified comprehensive percentile tables are provided for most relevant cardiac parameters. Interpretation: This cross-sectional study provides overall and sex-stratified CMR reference values for cardiac dimensions and function, and myocardial tissue properties, in adolescents. This information is useful for clinical practice and may help in the differential diagnosis of cardiac diseases, such as cardiomyopathies and myocarditis, in this population. Funding: Instituto de Salud Carlos III (PI19/01704).

Machine Learning to Optimize the Echocardiographic Follow-Up of Aortic Stenosis.

BACKGROUND: Disease progression in patients with mild-to-moderate aortic stenosis is heterogenous and requires periodic echocardiographic examinations to evaluate severity. OBJECTIVES: This study sought to explore the use of machine learning to optimize aortic stenosis echocardiographic surveillance automatically. METHODS: The study investigators trained, validated, and externally applied a machine learning model to predict whether a patient with mild-to-moderate aortic stenosis will develop severe valvular disease at 1, 2, or 3 years. Demographic and echocardiographic patient data to develop the model were obtained from a tertiary hospital consisting of 4,633 echocardiograms from 1,638 consecutive patients. The external cohort was obtained from an independent tertiary hospital, consisting of 4,531 echocardiograms from 1,533 patients. Echocardiographic surveillance timing results were compared with the European and American guidelines echocardiographic follow-up recommendations. RESULTS: In internal validation, the model discriminated severe from nonsevere aortic stenosis development with an area under the receiver-operating characteristic curve (AUC-ROC) of 0.90, 0.92, and 0.92 for the 1-, 2-, or 3-year interval, respectively. In external application, the model showed an AUC-ROC of 0.85, 0.85, and 0.85, for the 1-, 2-, or 3-year interval. A simulated application of the model in the external validation cohort resulted in savings of 49% and 13% of unnecessary echocardiographic examinations per year compared with European and American guideline recommendations, respectively. CONCLUSIONS: Machine learning provides real-time, automated, personalized timing of next echocardiographic follow-up examination for patients with mild-to-moderate aortic stenosis. Compared with European and American guidelines, the model reduces the number of patient examinations.

Multicenter clinical trial for the resection of rectal polyps using a new laparoendoscopic hybrid transanal access device.

INTRODUCTION: Complex polyps require the use of advanced endoscopic techniques or minimally invasive surgery for their approach. In rectal polyps it is of special relevance to reach a consensus on the best approach to avoid under- or overtreatment that increases unnecessary morbidity and mortality. METHODS: We describe a prospective, multicenter, pilot clinical trial with a first-in-human medical device. It is hypothesized that UNI-VEC® facilitates transanal laparoendoscopic surgery for the removal of early rectal tumors. The primary objective is to evaluate that it is safe and meets the established functional requirements. Secondary objectives are to evaluate results, complications and level of satisfaction. RESULTS: 16 patients were recruited in 12 months with a minimum follow-up of 2 months. The mean size was 3.4 cm with the largest polyp being 6 cm. Regarding location, the mean was 6.6 cm from the anal margin. Endoscopic Mucosal Resection (EMR) (6.3%), Endoscopic Submucosal Dissection ESD (43.8%), REC (6.3%) and TAMIS (43.8%) were performed. The mean time was 73.25 min. The 56.3% used a 30° camera and 43.8% used the flexible endoscope as a viewing instrument. The 56.3% were benign lesions and 43.8% malignant. Complete resection is achieved in 87.5%. Regarding complications, mild bleeding (Clavien I) occurred in 25%, 6.3% and 21.4% at 24 h, 48 h and 7 days respectively. Continence was assessed according to the Wexner scale. At 7 days, 60% showed perfect continence, 26.7% mild FI and 13.3% moderate FI. At 30 days, 66.7% had perfect continence, 20% mild FI and 13.3% moderate FI. At 2 months, 4 patients were reviewed who at 30 days had a Wexner's degree higher than preoperative and perfect continence was demonstrated in 25% of the patients, 50% mild and 25% moderate. In no case did rectal perforation or major complications requiring urgent reintervention occur. As for the level of reproducibility, safety, level of satisfaction with the device and evaluation of the blister, the evaluation on a scale of 0-10 (9.43, 9.71, 9.29 and 9.50 respectively). All the investigators have previous experience with transanal devices. CONCLUSIONS: The study demonstrates the efficacy and safety of UNI-VEC® for the treatment of rectal lesions. It will facilitate the implementation of hybrid procedures that seek to solve the limitations of pure endoscopic techniques by allowing the concomitant use of conventional laparoscopic and robotic instrumentation with the flexible endoscope.

Neutrophil ß1 adrenoceptor blockade blunts stroke-associated neuroinflammation.

BACKGROUND AND PURPOSE: Reperfusion therapy is the standard of care for ischaemic stroke; however, there is a need to identify new therapeutic targets able to ameliorate cerebral damage. Neutrophil ß1 adrenoceptors (ß1AR) have been linked to neutrophil migration during exacerbated inflammation. Given the central role of neutrophils in cerebral damage during stroke, we hypothesize that ß1AR blockade will improve stroke outcomes. EXPERIMENTAL APPROACH: Rats were subjected to middle cerebral artery occlusion-reperfusion to evaluate the effect on stroke of the selective ß1AR blocker metoprolol (12.5 mg·kg-1 ) when injected i.v. 10 min before reperfusion. KEY RESULTS: Magnetic resonance imaging and histopathology analysis showed that pre-reperfusion i.v. metoprolol reduced infarct size. This effect was accompanied by reduced cytotoxic oedema at 24 h and vasogenic oedema at 7 days. Metoprolol-treated rats showed reduced brain neutrophil infiltration and those which infiltrated displayed a high proportion of anti-inflammatory phenotype (N2, YM1+ ). Additional inflammatory models demonstrated that metoprolol specifically blocked neutrophil migration via ß1AR and excluded a significant effect on the glia compartment. Consistently, metoprolol did not protect the brain in neutrophil-depleted rats upon stroke. In patients suffering an ischaemic stroke, ß1AR blockade by metoprolol reduced circulating neutrophil-platelet co-aggregates. CONCLUSIONS AND IMPLICATIONS: Our findings describe that ß1AR blockade ameliorates cerebral damage by targeting neutrophils, identifying a novel therapeutic target to improve outcomes in patients with stroke. This therapeutic strategy is in the earliest stages of the translational pathway and should be further explored.

Rationale and Protocol of the Multimodality Evaluation of Antibody-Mediated Injury in Heart Transplantation (LEONE-HT) Observational Cross-Sectional Study.

INTRODUCTION: Heart transplant (HT) survival has barely improved in the last decades, which is unsatisfactory for many HT recipients. The development of anti-human leukocyte antigen (anti-HLA) antibodies in HT patients is associated with a cardiac allograft dysfunction. The mechanisms leading to this damage are unclear. The Multimodality Evaluation Of Antibody-Mediated Injury In Heart Transplantation (LEONE-HT) study aimed to thoroughly describe the damage inflicted on the myocardium by anti-HLA antibodies. METHODS AND ANALYSIS: The LEONE-HT study is a cohort study with a cross-sectional approach in which HT patients with positive anti-HLA antibodies are compared with coetaneous HT patients with negative anti-HLA antibodies. All patients will undergo a state-of-the-art multimodal assessment, including imaging techniques, coronary anatomy and physiology evaluations and histological and immunological analyses. The individual and combined primary outcomes of structural graft injuries and longitudinal secondary outcomes are to be compared between the exposed and non-exposed groups with univariate and multivariable descriptive analyses. ETHICS AND DISSEMINATION: The LEONE-HT study is carried out in accordance with the principles set out in the Declaration of Helsinki and the International Conference on Harmonization guidelines for good clinical practice and following national laws and regulations. The study design, objectives and participant centers have been communicated to clinicaltrials.gov (NCT05184426). The LEONE-HT study counts on the support of patient associations to disseminate the objectives and results of the research. This study was funded by the Spanish Ministry of Science and Innovation and the Spanish Society of Cardiology.

New 3-Dimensional Volumetric Ultrasound Method for Accurate Quantification of Atherosclerotic Plaque Volume.

BACKGROUND: Carotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)-matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging. OBJECTIVES: This study aimed to validate this method for plaque volume measurement in early and intermediate-advanced plaques in the carotid and femoral territories. METHODS: Plaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate-high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)-based plaque quantification software. RESULTS: In the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 µL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 µL-859 µL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%. CONCLUSIONS: 3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate-advanced plaques located in carotid and femoral arteries.

Brief Research Report: Quantitative Analysis of Potential Coronary Microvascular Disease in Suspected Long-COVID Syndrome.

Background: Case series have reported persistent cardiopulmonary symptoms, often termed long-COVID or post-COVID syndrome, in more than half of patients recovering from Coronavirus Disease 19 (COVID-19). Recently, alterations in microvascular perfusion have been proposed as a possible pathomechanism in long-COVID syndrome. We examined whether microvascular perfusion, measured by quantitative stress perfusion cardiac magnetic resonance (CMR), is impaired in patients with persistent cardiac symptoms post-COVID-19. Methods: Our population consisted of 33 patients post-COVID-19 examined in Berlin and London, 11 (33%) of which complained of persistent chest pain and 13 (39%) of dyspnea. The scan protocol included standard cardiac imaging and dual-sequence quantitative stress perfusion. Standard parameters were compared to 17 healthy controls from our institution. Quantitative perfusion was compared to published values of healthy controls. Results: The stress myocardial blood flow (MBF) was significantly lower [31.8 ± 5.1 vs. 37.8 ± 6.0 (µl/g/beat), P < 0.001] and the T2 relaxation time was significantly higher (46.2 ± 3.6 vs. 42.7 ± 2.8 ms, P = 0.002) post-COVID-19 compared to healthy controls. Stress MBF and T1 and T2 relaxation times were not correlated to the COVID-19 severity (Spearman r = -0.302, -0.070, and -0.297, respectively) or the presence of symptoms. The stress MBF showed a U-shaped relation to time from PCR to CMR, no correlation to T1 relaxation time, and a negative correlation to T2 relaxation time (Pearson r = -0.446, P = 0.029). Conclusion: While we found a significantly reduced microvascular perfusion post-COVID-19 compared to healthy controls, this reduction was not related to symptoms or COVID-19 severity.

High-Resolution Free-Breathing Quantitative First-Pass Perfusion Cardiac MR Using Dual-Echo Dixon With Spatio-Temporal Acceleration.

Introduction: To develop and test the feasibility of free-breathing (FB), high-resolution quantitative first-pass perfusion cardiac MR (FPP-CMR) using dual-echo Dixon (FOSTERS; Fat-water separation for mOtion-corrected Spatio-TEmporally accelerated myocardial peRfuSion). Materials and Methods: FOSTERS was performed in FB using a dual-saturation single-bolus acquisition with dual-echo Dixon and a dynamically variable Cartesian k-t undersampling (8-fold) approach, with low-rank and sparsity constrained reconstruction, to achieve high-resolution FPP-CMR images. FOSTERS also included automatic in-plane motion estimation and T 2 * correction to obtain quantitative myocardial blood flow (MBF) maps. High-resolution (1.6 x 1.6 mm2) FB FOSTERS was evaluated in eleven patients, during rest, against standard-resolution (2.6 x 2.6 mm2) 2-fold SENSE-accelerated breath-hold (BH) FPP-CMR. In addition, MBF was computed for FOSTERS and spatial wavelet-based compressed sensing (CS) reconstruction. Two cardiologists scored the image quality (IQ) of FOSTERS, CS, and standard BH FPP-CMR images using a 4-point scale (1-4, non-diagnostic - fully diagnostic). Results: FOSTERS produced high-quality images without dark-rim and with reduced motion-related artifacts, using an 8x accelerated FB acquisition. FOSTERS and standard BH FPP-CMR exhibited excellent IQ with an average score of 3.5 ± 0.6 and 3.4 ± 0.6 (no statistical difference, p > 0.05), respectively. CS images exhibited severe artifacts and high levels of noise, resulting in an average IQ score of 2.9 ± 0.5. MBF values obtained with FOSTERS presented a lower variance than those obtained with CS. Discussion: FOSTERS enabled high-resolution FB FPP-CMR with MBF quantification. Combining motion correction with a low-rank and sparsity-constrained reconstruction results in excellent image quality.

Bone marrow activation in response to metabolic syndrome and early atherosclerosis.

AIMS: Experimental studies suggest that increased bone marrow (BM) activity is involved in the association between cardiovascular risk factors and inflammation in atherosclerosis. However, human data to support this association are sparse. The purpose was to study the association between cardiovascular risk factors, BM activation, and subclinical atherosclerosis. METHODS AND RESULTS: Whole body vascular 18F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging (18F-FDG PET/MRI) was performed in 745 apparently healthy individuals [median age 50.5 (46.8-53.6) years, 83.8% men] from the Progression of Early Subclinical Atherosclerosis (PESA) study. Bone marrow activation (defined as BM 18F-FDG uptake above the median maximal standardized uptake value) was assessed in the lumbar vertebrae (L3-L4). Systemic inflammation was indexed from circulating biomarkers. Early atherosclerosis was evaluated by arterial metabolic activity by 18F-FDG uptake in five vascular territories. Late atherosclerosis was evaluated by fully formed plaques on MRI. Subjects with BM activation were more frequently men (87.6 vs. 80.0%, P = 0.005) and more frequently had metabolic syndrome (MetS) (22.2 vs. 6.7%, P < 0.001). Bone marrow activation was significantly associated with all MetS components. Bone marrow activation was also associated with increased haematopoiesis-characterized by significantly elevated leucocyte (mainly neutrophil and monocytes) and erythrocyte counts-and with markers of systemic inflammation including high-sensitivity C-reactive protein, ferritin, fibrinogen, P-selectin, and vascular cell adhesion molecule-1. The associations between BM activation and MetS (and its components) and increased erythropoiesis were maintained in the subgroup of participants with no systemic inflammation. Bone marrow activation was significantly associated with high arterial metabolic activity (18F-FDG uptake). The co-occurrence of BM activation and arterial 18F-FDG uptake was associated with more advanced atherosclerosis (i.e. plaque presence and burden). CONCLUSION: In apparently healthy individuals, BM 18F-FDG uptake is associated with MetS and its components, even in the absence of systemic inflammation, and with elevated counts of circulating leucocytes. Bone marrow activation is associated with early atherosclerosis, characterized by high arterial metabolic activity. Bone marrow activation appears to be an early phenomenon in atherosclerosis development.[Progression of Early Subclinical Atherosclerosis (PESA); NCT01410318].

Coronary microcirculation damage in anthracycline cardiotoxicity.

AIMS: The aim of this study was to study changes in coronary microcirculation status during and after several cycles of anthracycline treatment. METHODS AND RESULTS: Large-white male pigs (n=40) were included in different experimental protocols (ExPr.) according to anthracycline cumulative exposure [0.45 mg/kg intracoronary (IC) doxorubicin per injection] and follow-up: control (no doxorubicin); single injection and sacrifice either at 48 h (ExPr. 1) or 2 weeks (ExPr. 2); 3 injections 2 weeks apart (low cumulative dose) and sacrifice either 2 weeks (ExPr. 3) or 12 weeks (ExPr. 4) after third injection; five injections 2 weeks apart (high cumulative dose) and sacrifice 8 weeks after fifth injection (ExPr. 5). All groups were assessed by serial cardiac magnetic resonance (CMR) to quantify perfusion and invasive measurement of coronary flow reserve (CFR). At the end of each protocol, animals were sacrificed for ex vivo analyses. Vascular function was further evaluated by myography in explanted coronary arteries of pigs undergoing ExPr. 3 and controls. A single doxorubicin injection had no impact on microcirculation status, excluding a direct chemical toxicity. A series of five fortnightly doxorubicin injections (high cumulative dose) triggered a progressive decline in microcirculation status, evidenced by reduced CMR-based myocardial perfusion and CFR-measured impaired functional microcirculation. In the high cumulative dose regime (ExPr. 5), microcirculation changes appeared long before any contractile defect became apparent. Low cumulative doxorubicin dose (three bi-weekly injections) was not associated with any contractile defect across long-term follow-up, but provoked persistent microcirculation damage, evident soon after third dose injection. Histological and myograph evaluations confirmed structural damage to arteries of all calibres even in animals undergoing low cumulative dose regimes. Conversely, arteriole damage and capillary bed alteration occurred only after high cumulative dose regime. CONCLUSION: Serial in vivo evaluations of microcirculation status using state-of-the-art CMR and invasive CFR show that anthracyclines treatment is associated with progressive and irreversible damage to the microcirculation. This long-persisting damage is present even in low cumulative dose regimes, which are not associated with cardiac contractile deficits. Microcirculation damage might explain some of the increased incidence of cardiovascular events in cancer survivors who received anthracyclines without showing cardiac contractile defects.