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We study linear spaces of symmetric matrices whose reciprocal is also a linear space. These are Jordan algebras. We classify such algebras in low dimensions, and we study the associated Jordan loci in the Grassmannian. [ABSTRACT FROM AUTHOR]

Objectives: We evaluated a large multicenter series of patients operated on for low-flow/low-gradient aortic stenosis (LF/LGAS) to stratify the operative risk, assess whether perioperative mortality has decreased over recent years, and analyze the post-operative outcome. Background: Although LF/LGAS is classically associated with a high operative risk, few data are available concerning the results of surgery in this setting. Methods: A total of 217 consecutive patients (168 men, 77%) with severe aortic stenosis (area <1 cm(2)), low ejection fraction (EF) (Results: Perioperative mortality was 16% and decreased dramatically from 20% in the 1990 to 1999 period to 10% in the 2000 to 2005 period. Higher European System for Cardiac Operative Risk Evaluation score (EuroSCORE), very low MG and EF, New York Heart Association functional class III or IV, history of congestive heart failure, and multivessel coronary artery disease (MVD) were associated with perioperative mortality. On multivariate analysis, very low pre-operative MG and MVD were predictors of excess perioperative mortality. In the subgroup of patients with dobutamine stress echocardiography, the absence of contractile reserve was a strong predictor of perioperative mortality. Overall 5-year survival rate was 49 +/- 4%. Lower MG, higher EuroSCORE, prior atrial fibrillation, and MVD were identified as independent predictors of overall long-term mortality. Conclusions: In view of the very poor prognosis of unoperated patients, the current operative risk, and the long-term outcome after surgery, AVR is the treatment of choice in the majority of cases of LF/LGAS. [ABSTRACT FROM AUTHOR]

A Jordan net (resp. web) is an embedding of a unital Jordan algebra of dimension 3 (resp. 4) into the space S n of symmetric n × n matrices. We study the geometries of Jordan nets and webs: we classify the congruence orbits of Jordan nets (resp. webs) in S n for n ≤ 7 (resp. n ≤ 5 ), we find degenerations between these orbits and list obstructions to the existence of such degenerations. For Jordan nets in S n for n ≤ 5 , these obstructions show that our list of degenerations is complete . For n = 6 , the existence of one degeneration is still undetermined. To explore further, we used an algorithm that indicates numerically whether a degeneration between two orbits exists. We verified this algorithm using all known degenerations and obstructions and then used it to compute the degenerations between Jordan nets in S 7 and Jordan webs in S n for n = 4 , 5 ., Competing Interests: Conflict of interestThe authors state that there is no conflict of interest., (© The Author(s) 2022.)

Background: Acute kidney injury (AKI) is associated with a dismal prognosis in Transcatheter Aortic Valve replacement (TAVR). Acute kidney recovery (AKR), a phenomenon reverse to AKI has recently been associated with better outcomes., Methods: Between November 2012 to May 2018, we explored consecutive patients referred to our Heart Valve Center for TAVR. AKI was defined according to the VARC-2 definition. Mirroring the VARC-2 definition of AKI, AKR was defined as a decrease in serum creatinine (≥50%) or ≥25% improvement in GFR up to 72 hours after TAVR., Results: AKI and AKR were respectively observed in 8.3 and 15.7% of the 574 patients included. AKI and AKR patients were associated to more advanced kidney disease at baseline. At a median follow-up of 608 days (range 355-893), AKI and AKR patients experienced an increased cardiovascular mortality compared to unchanged renal function patients (14.6% and 17.8% respectively, vs. 8.1%, CI 95%, p<0.022). Chronic kidney disease, (HR: 3.9; 95% CI 1.7-9.2; p < 0.001) was the strongest independent factor associated with AKI similarly to baseline creatinine level (HR: 1; 95% CI 1 to 1.1 p < 0.001) for AKR. 72-hours post procedural AKR (HR: 2.26; 95% CI 1.14 to 4.88; p = 0.021) was the strongest independent predictor of CV mortality., Conclusions: Both AKR and AKI negatively impact long term clinical outcomes of patients undergoing TAVR., Competing Interests: The authors have declared that no competing interests exist.

Background and purpose-current guidelines recommend the use of transesophageal echocardiography (TEE) in relation to cardio-embolic sources of stroke. Methods-by using an hospital-based cohort, we retrospectively analyzed consecutive patients with acute ischemic stroke (AIS), acute hemorrhagic stroke (AHS) and transient ischemic attack (TIA) who were admitted in Strasbourg Stroke Center, France between November 2017 to December 2018. TEE reports were screened for detection of potential cardiac sources of embolism and the subsequent change in medical management. We performed univariate and multivariate analyses to identify predictors of relevant TEE findings. Results-out of the 990 patients admitted with confirmed stroke, 432 patients (42.6%) underwent TEE. Patients with TEE were younger (62.8 ± 14.8 vs. 73.8, p < 0.001), presented less comorbidities and lower stroke severity assessed by lower NIHSS (2 IQR (0-4) vs. 3 IQR (0-10), p < 0.01) and Modified Rankin Scale (1 IQR (0-1) vs. 1 (0-3), p < 0.01). A total of 227 examinations (52.5%) demonstrated abnormal findings considered as potential cardiac sources of embolism and 31 examinations (7.1%) were followed by subsequent change in medical management. Age (HR: 0.948, 95% CI 0.923 to 0.974; p < 0.001), previous AIS (HR: 3.542, 95% CI 1.290 to 9.722; p = 0.01), previous TIA (HR: 7.830, CI 95% 2214 to 27,689; p = 0.001) and superficial middle cerebral artery territory infarction (HR: 2.774, CI 95% 1.168-6.589; p = 0.021) were strong independent predictors with change in medical management following TEE. Conclusions-additional TEE changed the medical course of stroke patients in 7.1% in a French high-volume stroke unit.

Background Electrocardiographic strain pattern (ESP) has recently been associated with increased adverse outcome in aortic stenosis and after surgical aortic valve replacement. Our study sought to determine the impact and incremental value of ESP pattern in predicting adverse outcome after transcatheter aortic valve replacement. Methods and Results A total of 585 patients with severe aortic stenosis (mean age, 83±7 years; men, 39.8%) were enrolled for transcatheter aortic valve replacement from November 2012 to May 2018. ESP was defined as ≥1-mm concave down-sloping ST-segment depression and asymmetrical T-wave inversion in the lateral leads. The primary end points of the study were all-cause mortality, rehospitalization for heart failure, myocardial infarction, and stroke. A total of 178 (30.4%) patients were excluded because of left bundle-branch block (n=103) or right bundle-branch block (n=75). Among the 407 remaining patients, 106 had ESP (26.04%). At a median follow-up of 20.00 months (11.70-29.42 months), no impact of electric strain on overall and cardiac death could be established. By contrast, incidence of rehospitalization for heart failure was significantly higher (33/106 [31.1%] versus 33/301 [11%]; P <0.001) in patients with ESP. By multivariate analyses, ESP remained a strong predictor of rehospitalization for heart failure (hazard ratio, 2.75 [95% CI, 1.61-4.67]; P <0.001). Conclusions In patients with aortic stenosis who were eligible for transcatheter aortic valve replacement, ESP is frequent and associated with an increased risk of postinterventional heart failure regardless of preoperative left ventricular hypertrophy. ESP represents an easy, objective, reliable, and low-cost tool to identify patients who may benefit from intensified postinterventional follow-up.

Acute kidney injury (AKI) following transcatheter aortic valve replacement (TAVR) is associated with a dismal prognosis. Elevated renal resistive index (RRI), through renal Doppler ultrasound (RDU) evaluation, has been associated with AKI development and increased systemic arterial stiffness. Our pilot study aimed to investigate the performance of Doppler based RRI to predict AKI and outcomes in TAVR patients. From May 2018 to May 2019, 100 patients with severe aortic stenosis were prospectively enrolled for TAVR and concomitant RDU evaluation at our institution (Nouvel Hôpital Civil, Strasbourg University, France). AKI by serum Creatinine (sCr-AKI) was defined according to the VARC-2 definition and AKI by serum Cystatin C (sCyC-AKI) was defined as an sCyC increase of greater than 15% with baseline value. Concomitant RRI measurements as well as renal and systemic hemodynamic parameters were recorded before, one day, and three days after TAVR. It was found that 10% of patients presented with AKI sCr and AKI sCyC . The whole cohort showed higher baseline RRI values (0.76 ± 0.7) compared to normal known and accepted values. AKI sCyC had significant higher post-procedural RRI one day (Day 1) after TAVR (0.83 ± 0.1 vs. 0.77 ± 0.6, CI 95%, p = 0.005). AUC for AKI sCyC was 0.766 and a RRI cut-off value of ≥ 0.795 had the most optimal sensitivity/specificity (80/62%) combination. By univariate Cox analysis, Mehran Risk Score, higher baseline right atrial pressure at baseline > 0.8 RRI values one day after TAVR (HR 6.5 (95% CI 1.3-32.9; p = 0.021) but not RRI at baseline were significant predictors of AKI sCyC . Importantly, no significant impact of baseline biological parameters, renal or systemic parameters could be demonstrated. Doppler-based RRI can be helpful for the non-invasive assessment of AKI development after TAVR., Competing Interests: Dr. Matsushita has received scholarship from Uehara Memorial Foundation. Other authors have reported that they have no relationship to disclose.

Reactive oxygen species (ROS) are central bioenergetic markers linked to aortic stenosis (AS) development and severity. We sought to evaluate the time course and impact of ROS assessed by plasmatic superoxide anion (SA) among patients undergoing transcatheter aortic valve replacement (TAVR). Among 106 patients, SA significantly decreased after TAVR. Dropped values were measured 10 min after TAVR (0.590 ± 0.181 vs. 0.648 ± 0.193; p  < 0.001) and persistent at 3 days (0.611 ± 0.0.228 vs. 0.646 ± 0.199; p  = 0.033) and 30 days follow-up (0.572 ± 0.207 vs. 0.639 ± 0.199; p  = 0.005). Increased baseline SA (>75 percentile) was continuously associated with higher postprocedural SA values 10 min after valve expansion ( p  < 0.001), at 3 days ( p  < 0.001) and 30 days ( p  < 0.001). Higher baseline SA was linked to higher inflammatory response assessed by higher C-reactive protein values at day 1 and day 3. The composite endpoint of all-cause mortality and/or stroke and/or pacemaker implantation and/or significant paravalvular aortic regurgitation ≥mild at 30 days did not differ significantly according to SA baseline values ( p  = 0.055). This is the first report identifying a decrease in oxidative stress level after TAVR. Our observation leads to the hypothesis that oxidative stress biomarkers may survive the journey from bench to bedside in AS and TAVR and become new biomarkers with both diagnostic and prognostic values. Antioxid. Redox Signal. 31, 420-426.

Background: Infective endocarditis (IE) remains a severe disease with a high mortality rate. Therefore, guidelines encourage the setup of a multidisciplinary group in reference centers. The present study evaluated the impact of this "Endocarditis Team" (ET)., Methods: We conducted a monocentric observational study at Strasbourg University Hospital, Strasbourg, France, between 2012 and 2017. The primary end point was in-hospital mortality. Secondary end points were 6-month and 1-year mortality, surgery rate, time to surgical procedure, duration of effective antibiotic therapy, length of in-hospital stay, and sequelae. We also assessed predictors of in-hospital mortality., Results: We analyzed 391 episodes of IE. In the post-ET period, there was a nonsignificant decrease in in-hospital mortality (20.3% vs 14.7%, respectively; P = .27) and sequelae, along with a significant reduction in time to surgery (16.4 vs 10.3 days, respectively; P = .049), duration of antibiotic therapy (55.2 vs 47.2 days, respectively; P < .001), and length of in-hospital stay (40.6 vs 31.9 days, respectively; P < .01). In a multivariate analysis, the post-ET period was positively associated with survival (odds ratio, 0.45; 95% confidence interval, 0.20-0.96; P = .048)., Conclusions: This multidisciplinary approach exerted a positive impact on the management of IE and should be considered in all hospitals managing IE., (© The Author(s) 2019. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Background: Periprocedural and late (>30 days) bleedings represent major complications after transcatheter aortic valve replacement and have been identified as potential areas for improved patient care., Objectives: The authors sought to evaluate the impact of ongoing primary hemostasis disorders on late major/life-threatening bleeding complications (MLBCs)., Methods: Bleedings were assessed according to the VARC-2 (Valve Academic Research Consortium-2) criteria. Closure time of adenosine diphosphate (CT-ADP), a surrogate marker of high molecular weight von Willebrand multimers proteolysis was assessed 24 h after the procedure. Ongoing primary hemostasis disorder was defined by a CT-ADP >180 s., Results: Among 372 patients who survived at 30 days, MLBCs occurred in 42 patients (11.3%) at a median follow-up of 383 days (interquartile range: 188 to 574 days). MLBCs were mainly of gastrointestinal origin (42.8%) and were associated with increased overall mortality (hazard ratio [HR]: 5.66; 95% confidence interval [CI]: 3.10 to 10.31; p < 0.001) and cardiac mortality (HR: 11.62; 95% CI: 4.59 to 29.37; p < 0.001). A 2.5-fold elevation of MLBCs could be evidenced in patients with a CT-ADP > 180 s (27.4% vs. 11.5%; p < 0.001). Multivariate regression analysis identified paravalvular leak (PVL) (HR: 6.31; 95% CI: 3.43 to 11.60; p < 0.0001) and CT-ADP > 180 s (HR: 3.08; 95% CI: 1.62 to 5.81; p = 0.0005) as predictor of MLBCs., Conclusions: MLBCs after transcatheter aortic valve replacement are frequent and associated with an increased morbidity and mortality. PVL and CT-ADP >180 s were identified as strong predictors for MLBCs. These findings strongly suggest that persistent HMW defects contribute to enhanced bleeding risk in patients with residual PVL., (Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Paravalvular aortic regurgitation (PVAR) remains a frequent postprocedural concern following transcatheter aortic valve replacement (TAVR). Persistence of flow turbulence results in the cleavage of high-molecular-weight von Willebrand multimers, primary haemostasis dysfunction and may favour bleedings. Recent data have emphasized the value of a point-of-care measure of von Willebrand factor-dependent platelet function (closure time [CT] adenosine diphosphate [ADP]) in the monitoring of immediate PVAR. This study examined whether CT-ADP could detect PVAR at 30 days and bleeding complications following TAVR., Methods: CT-ADP was assessed at baseline and the day after the procedure. At 30 days, significant PVAR was defined as a circumferential extent of regurgitation more than 10% by transthoracic echocardiography. Events at follow-up were assessed according to the Valve Academic Research Consortium-2 consensus classification., Results: Significant PVAR was diagnosed in 44 out of 219 patients (20.1%). Important reduction of CT-ADP could be found in patients without PVAR, contrasting with the lack of CT-ADP improvement in significant PVAR patients. By multivariate analysis, CT-ADP > 180 seconds (hazard ratio [HR]: 5.1, 95% confidence interval [CI]: 2.5-10.6; p  < 0.001) and a self-expandable valve were the sole independent predictors of 30-day PVAR. At follow-up, postprocedural CT-ADP >180 seconds was identified as an independent predictor of major/life-threatening bleeding (HR: 1.7, 95% CI [1.0-3.1]; p  = 0.049). Major/life-threatening bleedings were at their highest levels in patients with postprocedural CT-ADP > 180 seconds (35.2 vs. 18.8%; p  = 0.013)., Conclusion: Postprocedural CT-ADP > 180 seconds is an independent predictor of significant PVAR 30 days after TAVR and may independently contribute to major/life-threatening bleedings., Competing Interests: None., (Schattauer GmbH Stuttgart.)

Biostimulation is widely used to enhance reductive dechlorination of chlorinated ethenes in contaminated aquifers. However, the knowledge on corresponding biogeochemical responses is limited. In this study, glycerol was injected in an aquifer contaminated with cis-dichloroethene (cDCE), and geochemical and microbial shifts were followed for 265 days. Consistent with anoxic conditions and sulfate reduction after biostimulation, MiSeq 16S rRNA gene sequencing revealed temporarily increased relative abundance of Firmicutes, Bacteriodetes and sulfate reducing Deltaproteobacteria. In line with 13 C cDCE enrichment and increased Dehalococcoides mccartyi (Dcm) numbers, dechlorination was observed toward the end of the field experiment, albeit being incomplete with accumulation of vinyl chloride. This was concurrent with (i) decreased concentrations of dissolved organic carbon (DOC), reduced relative abundances of fermenting and sulfate reducing bacteria that have been suggested to promote Dcm growth by providing electron donor (H 2 ) and essential corrinoid cofactors, (ii) increased sulfate concentration and increased relative abundance of Epsilonproteobacteria and Deferribacteres as putative oxidizers of reduced sulfur compounds. Strong correlations of DOC, relative abundance of fermenters and sulfate reducers, and dechlorination imply the importance of syntrophic interactions to sustain robust dechlorination. Tracking microbial and environmental parameters that promote/preclude enhanced reductive dechlorination should aid development of sustainable bioremediation strategies., (© 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Objectives: Prosthesis-patient mismatch (PPM) has been reported to impact early haemodynamic status and early mortality after prosthetic aortic valve replacement (AVR) in patients with aortic stenosis (AS). The aim of this study was to assess the impact of PMM on early haemodynamic status after AVR using vasoactive-inotropic dependency index (VDI), postoperative pressures and end-organ perfusion., Methods: A total of 183 patients with AS were included in this prospective cohort study, and underwent elective AVR with or without combined coronary artery bypass graft surgery. PPM was defined as a projected indexed effective orifice area of ≤0.85 cm 2 /m 2 , and was present in 27.9% of the patients. The primary end-point was the VDI [VDI = vasoactive-inotropic score/mean arterial pressure] measured upon admission to the intensive care unit (POD0) and on the morning of the first postoperative day (POD1). The secondary end-points were the following: mean left atrial pressure, mean central venous pressure, fluid balance, brain natriuretic peptide, troponin I, glomerular filtration rate and lactate levels on POD0 and POD1., Results: No significant differences in VDI were observed between the no PPM and PPM groups on POD0 (0.08 ± 0.48 vs 0.05 ± 0.13, respectively, P = 0.622) or on POD1 (0.09 ± 0.40 vs 0.06 ± 0.13, respectively; P = 0.583). The mean arterial pressure, mean left atrial pressure, central venous pressure, troponin I, glomerular filtration rate and lactate levels did not differ between the two groups on POD0 and POD1, as well as fluid balance and brain natriuretic peptide on POD1., Conclusions: PPM is not associated with early haemodynamic status impairment and end-organ perfusion after AVR., Clinical Trial Number: ClinicalTrials.gov number, NCT00699673., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: The impact of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) for aortic stenosis on exercise capacity remains controversial. The aim of this study was to analyze the long-term impact of PPM after mechanical AVR on maximal oxygen uptake (VO 2max )., Methods: The study included 75 patients who had undergone isolated mechanical AVR for aortic stenosis with normal left ventricular (LV) function between 1994 and 2012. Their functional capacity was evaluated on average 4.6 years after AVR by exercise testing, including measurement of their VO 2max , and by determining their New York Heart Association functional class and Short Form-36 score. Two groups were defined by measuring the patients' indexed effective orifice area (iEOA) by transthoracic echocardiography: a PPM group (iEOA < 0.85 cm 2 /m 2 ) and a no-PPM group (iEOA ≥ 0.85 cm 2 /m 2 )., Results: PPM was present in 37.0% of the patients. The percentage of the predicted VO 2max achieved was significantly lower in the PPM group (86.7 ± 19.5% vs 97.5 ± 23.0% in the no-PPM group; P = 0.04). Compared with the no-PPM group, the PPM group contained fewer patients in New York Heart Association functional class I and their mean Short Form-36 physical component summary score was significantly lower. The mean transvalvular gradient was significantly higher in the PPM group than in the no-PPM group (P < 0.001). Systolic and diastolic function and LV mass had normalized in both groups., Conclusions: PPM is associated in the long term with moderate but significant impairment of functional capacity, despite optimal LV reverse remodelling and normalization of LV systolic and diastolic function., (Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: We have been intrigued by the observation that aortic stenosis (AS) may be associated with characteristic features of mitral drug-induced valvular heart disease (DI-VHD) in patients exposed to valvulopathic drugs, thus suggesting that beyond restrictive heart valve regurgitation, valvulopathic drugs may be involved in the pathogenesis of AS., Methods: Herein are reported echocardiographic features, and pathological findings encountered in a series of patients suffering from both AS (mean gradient >15mmHg) and mitral DI-VHD after valvulopathic drugs exposure. History of rheumatic fever, chest radiation therapy, systemic disease or bicuspid aortic valve disease were exclusion criteria., Results: Twenty-five (19 females, mean age 62years) patients having both AS and typical features of mitral DI-VHD were identified. Mean transaortic pressure gradient was 32+/-13mmHg. Aortic regurgitation was ≥ mild in 24 (96%) but trivial in one. Known history of aortic valve regurgitation following drug initiation prior the development of AS was previously diagnosed in 17 patients (68%). Six patients underwent aortic valve replacement and 3 both aortic and mitral valve replacement. In the 9 patients with pathology analysis, aortic valvular endocardium was markedly thickened by dense non-inflammatory fibrosis, a characteristic feature of DI-VHD., Conclusion: The association between AS and typical mitral DI-VHD after valvulopathic drug exposure may not be fortuitous. Aortic regurgitation was usually associated to AS and preceded AS in most cases but may be lacking. Pathology demonstrated the potential role of valvulopathic drugs in the development of AS., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)