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Sadie Bennett

and 8 more

Background: Cardiac resynchronization therapy (CRT) in heart failure patients has been shown to improve patient outcomes in some but not all patients. A few studies have identified that septal flash on imaging is associated with response to CRT but there has yet to be systematic review to evaluate consistency of the finding across the literature. Methods: A search of MEDLINE and EMBASE was conducted to identify studies which evaluate septal flash and its association with CRT response. Studies that met the inclusion criteria were statistically pooled with random-effects meta-analysis and heterogeneity was assessed using the I2 statistic. Results: A total of nine studies were included with 2,307 participants (mean age 76 years, 67% male). Septal flash on imaging before CRT implantation was seen in 53% of patients and the proportion of CRT responders from the included studies varied from 52% to 77%. In patients who were CRT responders, septal flash was seen in 40% of patients compared to 10% in those deemed to be CRT non-responders. Meta-analysis of the eight studies suggests that the presence of septal flash at pre-implant was associated with an increased likelihood of CRT response (RR 2.55 95%CI 2.04-3.19, p<0.001, I2=51%). Septal flash was also reported to be associated with left ventricular reverse remodelling but the association with survival and symptomatic improvement was less clear. Conclusions: Septal flash is a well-defined and distinctive contraction pattern which is consistently associated with CRT response and should be evaluated when assessing for appropriateness of CRT device.
A four year old boy was diagnosed with hypertrophic cardiomyopathy with moderate degree of obstruction of the left ventricular outflow tract, secondary to asymmetric septal hypertrophy and no features of congestive heart failure, at the age of the 7 months. He was also found to have myxomatous mitral valve, systolic anterior motion of anterior mitral leaflet and moderate mitral regurgitation. There was no evidence of ventricular septal defect at this point in time.In view of phenotypic features suggestive of Noonan syndrome, he underwent genetic evaluation with target gene sequencing and was detected to have a novel heterozygous mutation in exon 13 of LZTR 1 (Leucine- zipper-like transcriptional regulator 1) gene. Echocardiogram on follow up showed increase in left ventricular outflow tract obstruction and appearance of an aneurysm in the membranous portion of interventricular septum. There were no features of right ventricular outflow obstruction, tricuspid regurgitation or aortic regurgitation. The appearance of the membranous septal aneurysm may be related to the direction of jet arising from the point of contact of the anterior mitral leaflet with the hypertrophied basal septum and hitting this part of the interventricular septum. It is an unusual mechanism for formation of membranous septal aneurysm, given its absence in the earlier echocardiograms and absence of any left to right shunt across the aneurysm. He has been initiated on beta blockers due to severe left ventricular outflow tract obstruction and is planned for septal myomectomy, resection of membranous septal aneurysm and mitral valve repair.

Satoshi Yanagisawa

and 9 more

Introduction: The risk of developing left atrial (LA) thrombi after initial catheter ablation for atrial fibrillation (AF) and requirements for imaging evaluation for thrombi screening at repeat ablation is unclear. This study aimed to assess the occurrence of thrombus development and frequency of any imaging study evaluating thrombus formation during repeat ablation for AF. Methods: Of 2,066 patients undergoing initial catheter ablation for AF with uninterrupted oral anticoagulation, 615 patients underwent repeat ablation after 258.0 (105.0-882.0) days. We investigated which factors were associated with safety outcomes and requirements for thrombi screening. Results: All patients underwent at least one imaging examination to screen for thrombi in the first session, but the examination rate decreased to 476 patients (77%) before the repeat procedure. The frequency of imaging evaluations was 5.0%, 11%, 21%, 84%, and 91% for transesophageal echocardiography and 18%, 33%, 49%, 98%, and 99% for any imaging modality at repeat ablation performed ≤60 days, ≤90 days, ≤180 days, >180 days, and >1 year after the initial procedure, respectively. Three patients (0.5%) developed LA thrombi at repeat ablation due to identifiable causes, and no patients had thromboembolic events when no imaging evaluation was performed. Multivariate analysis revealed that repeat ablation >180 days, non-paroxysmal atrial arrhythmias, and lower left ventricular ejection fraction were predictors of the risk of thrombus development. Conclusions: The risk development of thrombus at repeat ablation for AF was low. There needs to be a risk stratification for the requirement of imaging screening for thrombi at repeat ablation for AF.

Ndayisenga jeanine

and 5 more

Background: Acute malnutrition is a frequent comorbidity in children with cancer and is associated with poor cancer treatment outcomes.This study describes the prevalence of acute malnutrition and its predictors at time of cancer diagnosis at Mbarara Regional Referral Hospital (MRRH). Methods: This was a retrospective chart review of children <15 years of age at diagnosis of cancer seen at the Children’s Cancer Unit of MRRH between May 2017 and May 2019. Using a data extraction tool, information regarding demographics, anthropometry at admission and cancer diagnosis was extracted from the children’s medical records. Descriptive statistics and logistic regression analysis were used to determine the prevalence and patterns of acute malnutrition among children at diagnosis of cancer and the factors associated with acute malnutrition, respectively. The study was approved by the Mbarara University of Science and Technology Research and Ethics Committee. Results: One hundred and thirty-three children were included in the study with a mean age of 6.6 years (SD 3.9).54.9% of the children were male. Overall, 46 (34.6%) of subjects had acute malnutrition at time of cancer diagnosis. Of these, 25 (54.3%) had moderate acute malnutrition and 21/46 (45.7%) had severe acute malnutrition.The factors independently associated with acute malnutrition after multivariate logistical regression analysis were age >5 years (p<0.0001) and reduced appetite (p=0.002). Conclusion: Acute malnutrition is common among children with cancer at diagnosis, especially in older children and those reporting poor appetite. Nutrition assessment and care should be incorporated into routine childhood cancer care to improve cancer treatment outcomes.

Kidane Reda

and 4 more

Spatial rainfall data is an essential input to physically based, parametrically distributed hydrological models, and a main contributor to hydrological model uncertainty. Two important issues should be addressed before use of satellite and reanalysis rainfall product at basin level: 1) how useful are these rainfall estimates as forcing data for regional hydrological modeling? 2) which should be preferred for hydrological modelling at high flow and low flow seasons? To this end, rainfall estimates from a satellite-based product, CHIRPSv8, and reanalysis data, EWEMBI, were used as input to SWAT model, and mode performances were evaluated against streamflow measured at three gauge stations in the Upper Tekeze River basin, northern Ethiopia for the period of 2006-2015. Results showed that (I) the daily rainfall from both CHIRPSv8 and EWEMBI are close to the rain gauge data, with relative errors 2.12% and 3.85%, respectively; (II) the monthly streamflow simulated by the SWAT model driven by the CHIRPSv8 and EWEMBI had a Kling-Gupta Efficiency value of 0.6-0.79 and 0.58-0.64, respectively; (III) the SWAT model calibrated with the CHIRPSv8 and EWEMBI rainfall estimates has shown an improvement in hydrological performance compared with that calibrated with interpolated ground observations; (IV) the hydrological performance during high flow seasons is superior to low flow seasons for both CHIRPSv8 and EWEMBI, thus promoting the use of the products for applications focusing on the high flow conditions. In particular, CHIRPSv8 showed relatively better hydrologic performance than EWEMBI. This study provides insight on the usefulness of the gridded rainfall products for hydrological modeling and under which conditions they can be used to generate a plausible level of adequacy and reliability over the Upper Tekeze River basin.

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Gunter Sturm

and 38 more

Background: There is controversy whether taking β-blockers or ACE inhibitors (ACEI) is a risk factor for more severe systemic insect sting reactions (SSR) and whether it increases the number or severity of adverse events (AE) during venom immunotherapy (VIT). Methods: In this open, prospective, observational, multicenter trial, we recruited patients with a history of a SSR and indication for VIT. The primary objective of this study was to evaluate whether patients taking β-blockers or ACEI show more systemic AE during VIT compared to patients without such treatment. Results: In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. Of all patients included, 388 (27.2%) took antihypertensive (AHT) drugs (10.4% took β-blockers, 11.9% ACEI, 5.0% β-blockers and ACEI). Only 5.6% of patients under AHT treatment experienced systemic AE during VIT as compared with 7.4% of patients without these drugs (OR: 0.74, 95% CI: 0.43–1.22, p=0.25). The severity of the initial sting reaction was not affected by the intake of β-blockers or ACEI (OR: 1.14, 95% CI: 0.89–1.46, p=0.29). In total, 210 (17.7%) patients were re-stung during VIT and 191 (91.0%) tolerated the sting without systemic symptoms. Of the 19 patients with VIT treatment failure, 4 took β-blockers, none an ACEI. Conclusions: This trial provides robust evidence that taking β-blockers or ACEI does neither increase the frequency of systemic AE during VIT nor aggravate SSR. Moreover, results suggest that these drugs do not impair effectiveness of VIT. (Funded by Medical University of Graz, Austria; number, NCT04269629)

Nazanin Kermani

and 12 more

Background. Patients with severe asthma may have a greater risk of dying from COVID-19 disease. Angiotensin converting enzyme-2 (ACE2) and the enzyme proteases, transmembrane protease serine 2 (TMPRSS2) and FURIN, are needed for viral attachment and invasion into host cells. Methods. We examined microarray mRNA expression of ACE2, TMPRSS2 and FURIN in sputum, bronchial brushing and bronchial biopsies of the European U-BIOPRED cohort. Clinical parameters and molecular phenotypes, including asthma severity, sputum inflammatory cells, lung functions, oral corticosteroid (OCS) use, and transcriptomic-associated clusters, were examined in relation to gene expression levels. Results. ACE2 levels were significantly increased in sputum of severe asthma compared to mild-moderate asthma. In multivariate analyses, sputum ACE2 levels were positively associated with OCS use and male gender. Sputum FURIN levels were significantly related to neutrophils (%) and the presence of severe asthma. In bronchial brushing samples, TMPRSS2 levels were positively associated with male gender and body mass index, whereas FURIN levels with male gender and blood neutrophils. In bronchial biopsies, TMPRSS2 levels were positively related to blood neutrophils. The neutrophilic molecular phenotype characterised by high inflammasome activation expressed significantly higher FURIN levels in sputum than the eosinophilic Type 2-high or the pauci-granulocytic oxidative phosphorylation phenotypes. Conclusion. Levels of ACE2 and FURIN may differ by clinical or molecular phenotypes of asthma. Sputum FURIN expression levels were strongly associated with neutrophilic inflammation and with inflammasome activation. This might indicate the potential for a greater morbidity and mortality outcome from SARS-CoV-2 infection in neutrophilic severe asthma.

Xinyi Guan

and 4 more

Yasser Mubarak

and 1 more

Background: Small Aortic Annulus (AA) is big issue during Aortic Valve Replacement (AVR) necessitating replacement of an undersized prosthetic valve especially with Double Valve Replacement (DVR). Despite that small aortic valve prostheses can lead to Prosthesis-Patient Mismatch (PPM), there remains reluctance to perform aortic root enlargement (ARE) procedures fearing from morbidity and mortality. Objective: To evaluate clinical and echocardiographic outcomes in patients with small aortic annulus undergoing double valve replacement. Methods: The study included 100 consecutive patients underwent DVR for combined rheumatic aortic and mitral valve diseases, between Jan. 2016 and Sept. 2020. Only (50) patients had ARE with DVR. ARE was performed using an autologous or bovine pericardium or Dacron patch by Nicks or Manouguian procedures. The estimated postoperative end-points were mortality, effective orifice areas (EOA), mean aortic pressure gradient and valve-related complications. The least postoperative follow-up period was 6 months. Results: The study included 30 male and 70 female patients with mean age of 35±20 years, body surface area (BSA) of 1.7 ±0.3 m2, aortic annulus diameter was 20±1.4 mm, aortic orifice area was 0.8±0.1 cm2, and mean pressure gradient 85±2.5 mmHg. During follow-up period, there was a mild to moderate paravalvular leak (1%) with, (1%) heart block, and residual gradient on prosthetic aortic valve; that was all in DVR alone. Conclusion: Enlargement of aortic root by Nicks or Manouguian technique is safe and effective in patients with small aortic annulus undergoing double valve replacements.

Fabio Ramponi

and 6 more

Coronary artery and cerebrovascular disease represent a major cause of cardiovascular morbidity and mortality worldwide. Despite technological advancements in percutaneous interventions, surgical revascularization remains the preferred strategy in patients with left main or multivessel disease and in those with complex lesions with high SYNTAX score. As a result, an increasing number of older patients with diffuse atherosclerotic extracoronary disease are referred for coronary artery bypass grafting (CABG). Cerebrovascular complications after isolated coronary surgery occurs in 1-5% of patients; the magnitude of injury ranges from overt neurologic lesions with varying degree of permanent disability to “asymptomatic” cerebral events detected by dedicated neuro-imaging, nevertheless associated with significant long term cognitive and functional decline. Thromboembolic events due to manipulation of an atherosclerotic aorta are universally recognized as the leading etiology of early postoperative stroke following CABG. Coronary bypass surgery performed on an arrested heart relies on considerable aortic instrumentation associated with significant atheroembolic risk especially in older patients presenting with diffuse aortic calcifications. Surgical techniques to deal with a calcified ascending aorta during isolated coronary surgery have evolved over the last forty years. Moving away from aggressive aortic debridement or replacement, surgeons have developed strategies aimed to minimize aortic manipulation: from pump-assisted beating heart surgery with the use of composite grafts to complete avoidance of aortic manipulation with “anaortic” off-pump coronary artery bypass grafting, a safe and effective approach in significantly reducing the risk of intraoperative stroke.

Oktay Ucer

and 3 more

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