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In most sensory modalities, neuronal connectivity reflects behaviorally relevant stimulus features, such as spatial location, orientation, and sound frequency. By contrast, the prevailing view in the olfactory cortex, based on the reconstruction of dozens of neurons, is that connectivity is random. Here, we used high-throughput sequencing-based neuroanatomical techniques to analyze the projections of 5,309 mouse olfactory bulb and 30,433 piriform cortex output neurons at single-cell resolution. Surprisingly, statistical analysis of this much larger dataset revealed that the olfactory cortex connectivity is spatially structured. Single olfactory bulb neurons targeting a particular location along the anterior-posterior axis of piriform cortex also project to matched, functionally distinct, extra-piriform targets. Moreover, single neurons from the targeted piriform locus also project to the same matched extra-piriform targets, forming triadic circuit motifs. Thus, as in other sensory modalities, olfactory information is routed at early stages of processing to functionally diverse targets in a coordinated manner.
Assuntos
Córtex Olfatório , Condutos Olfatórios , Camundongos , Animais , Bulbo Olfatório , Neurônios/fisiologia , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
In developing olfactory bulb (OB), mitral cells (MCs) remodel their dendrites to establish the precise olfactory circuit, and these circuits are critical for individuals to sense odors and elicit behaviors for survival. However, how microtubules (MTs) participate in the process of dendritic remodeling remains elusive. Here, we reveal that calmodulin-regulated spectrin-associated proteins (CAMSAPs), a family of proteins that bind to the minus-end of the noncentrosomal MTs, play a crucial part in the development of MC dendrites. We observed that Camsap2 knockout (KO) males are infertile while the reproductive tract is normal. Further study showed that the infertility was due to the severe defects of mating behavior in male mice. Besides, mice with loss-of-function displayed defects in the sense of smell. Furthermore, we found that the deficiency of CAMSAP2 impairs the classical morphology of MCs, and the CAMSAP2-dependent dendritic remodeling process is responsible for this defect. Thus, our findings demonstrate that CAMSAP2 plays a vital role in regulating the development of MCs.
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Dendritos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos , Bulbo Olfatório , Olfato , Animais , Feminino , Masculino , Camundongos , Dendritos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/metabolismo , Morfogênese/genética , Bulbo Olfatório/metabolismo , Olfato/fisiologiaRESUMO
BACKGROUND: Diagnosis of mitral regurgitation (MR) requires careful evaluation by echocardiography with Doppler imaging. This study presents the development and validation of a fully automated deep learning pipeline for identifying apical 4-chamber view videos with color Doppler echocardiography and detecting clinically significant (moderate or severe) MR from transthoracic echocardiograms. METHODS: A total of 58 614 transthoracic echocardiograms (2 587 538 videos) from Cedars-Sinai Medical Center were used to develop and test an automated pipeline to identify apical 4-chamber view videos with color Doppler across the mitral valve and then assess MR severity. The model was tested internally on a test set of 1800 studies (80 833 videos) from Cedars-Sinai Medical Center and externally evaluated in a geographically distinct cohort of 915 studies (46 890 videos) from Stanford Healthcare. RESULTS: In the held-out Cedars-Sinai Medical Center test set, the view classifier demonstrated an area under the curve (AUC) of 0.998 (0.998-0.999) and correctly identified 3452 of 3539 echocardiography videos as having color Doppler information across the mitral valve (sensitivity of 0.975 [0.968-0.982] and specificity of 0.999 [0.999-0.999] compared with manually curated videos). In the external test cohort from Stanford Healthcare, the view classifier correctly identified 1051 of 1055 manually curated videos with color Doppler information across the mitral valve (sensitivity of 0.996 [0.990-1.000] and specificity of 0.999 [0.999-0.999]). In the Cedars-Sinai Medical Center test cohort, MR moderate or greater in severity was detected with an AUC of 0.916 (0.899-0.932) and severe MR was detected with an AUC of 0.934 (0.913-0.953). In the Stanford Healthcare test cohort, the model detected MR moderate or greater in severity with an AUC of 0.951 (0.924-0.973) and severe MR with an AUC of 0.969 (0.946-0.987). CONCLUSIONS: In this study, a novel automated pipeline for identifying clinically significant MR from full transthoracic echocardiography studies demonstrated excellent performance across large numbers of studies and across multiple institutions. Such an approach has the potential for automated screening and surveillance of MR.
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BACKGROUND: Previous transcatheter valve therapy registry analyses of transcatheter mitral valve in valve (MViV) replacement of degenerated bioprosthesis reported early experience in the United States. Given recent increases in transseptal MViV volumes and introduction of the SAPIEN 3 Ultra valve, it is important to determine contemporary outcomes for patients undergoing transseptal SAPIEN 3/SAPIEN 3 Ultra MViV replacement. METHODS: The Society of Thoracic Surgeons (STS)/American College of Cardiology Transcatheter Valve Therapy Registry was used to extract data for all patients undergoing transseptal SAPIEN 3/SAPIEN 3 Ultra MViV from 2015 to September 2022. Primary efficacy outcome was 1-year all-cause mortality. Secondary end points included 30-day mortality, functional class, quality of life, and mitral valve performance. Primary safety outcomes were device success and in-hospital complications. RESULTS: A total of 4243 patients with a mean STS score of 9.2±7.7 underwent transseptal MViV at 455 sites. The rate of Mitral Valve Academic Research Consortium technical (96.6%) success was high, and procedural complications were low. All-cause in-hospital, 30-day, and 1-year mortality rates were 3.2%, 4.3%, and 13.4%, respectively. Significant improvements in New York Heart Association class (New York Heart Association I/II, 18% to 87%) and quality of life (Kansas City Cardiomyopathy Questionnaire score, 38 to 78) were noted at 1 year (P<0.0001 for both) after MViV. Upon stratifying by STS scores, it was observed that the low-risk group (STS<4) had a significantly lower in-hospital mortality rate of 0.4%, whereas the intermediate-risk group (STS, 4-8) had an in-hospital mortality rate of 1.9%. From 2015 to 2022, the number of transseptal MViV cases/year increased significantly, whereas procedure times, length of stay, and intensive care unit hours shortened significantly. At the same time, there was a significant trend toward reduced in-hospital (P=0.0005), 30-day (P=0.004), and 1-year mortality rates (P=0.01). CONCLUSIONS: This multicenter, prospective study reports excellent procedural outcomes, 1-year mortality rates, and a significant improvement in quality of life for patients undergoing transseptal MViV in the contemporary era. Patients in the low-risk and intermediate-risk STS score categories had significantly better outcomes compared with those in the high-risk category. MViV is a reasonable therapy for the majority of patients with degenerated bioprosthetic mitral valves, who are anatomical candidates.
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BACKGROUND: Artificial intelligence, particularly deep learning (DL), has immense potential to improve the interpretation of transthoracic echocardiography (TTE). Mitral regurgitation (MR) is the most common valvular heart disease and presents unique challenges for DL, including the integration of multiple video-level assessments into a final study-level classification. METHODS: A novel DL system was developed to intake complete TTEs, identify color MR Doppler videos, and determine MR severity on a 4-step ordinal scale (none/trace, mild, moderate, and severe) using the reading cardiologist as a reference standard. This DL system was tested in internal and external test sets with performance assessed by agreement with the reading cardiologist, weighted κ, and area under the receiver-operating characteristic curve for binary classification of both moderate or greater and severe MR. In addition to the primary 4-step model, a 6-step MR assessment model was studied with the addition of the intermediate MR classes of mild-moderate and moderate-severe with performance assessed by both exact agreement and ±1 step agreement with the clinical MR interpretation. RESULTS: A total of 61 689 TTEs were split into train (n=43 811), validation (n=8891), and internal test (n=8987) sets with an additional external test set of 8208 TTEs. The model had high performance in MR classification in internal (exact accuracy, 82%; κ=0.84; area under the receiver-operating characteristic curve, 0.98 for moderate/severe MR) and external test sets (exact accuracy, 79%; κ=0.80; area under the receiver-operating characteristic curve, 0.98 for moderate or greater MR). Most (63% internal and 66% external) misclassification disagreements were between none/trace and mild MR. MR classification accuracy was slightly higher using multiple TTE views (accuracy, 82%) than with only apical 4-chamber views (accuracy, 80%). In subset analyses, the model was accurate in the classification of both primary and secondary MR with slightly lower performance in cases of eccentric MR. In the analysis of the 6-step classification system, the exact accuracy was 80% and 76% with a ±1 step agreement of 99% and 98% in the internal and external test set, respectively. CONCLUSIONS: This end-to-end DL system can intake entire echocardiogram studies to accurately classify MR severity and may be useful in helping clinicians refine MR assessments.
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BACKGROUND: The morbidity and mortality rates of patients with heart failure (HF) and functional mitral regurgitation (MR) remain substantial despite guideline-directed medical therapy for HF. We evaluated the efficacy of ertugliflozin for reduction of functional MR associated with HF with mild to moderately reduced ejection fraction. METHODS: The EFFORT trial (Ertugliflozin for Functional Mitral Regurgitation) was a multicenter, double-blind, randomized trial to examine the hypothesis that the sodium-glucose cotransporter 2 inhibitor ertugliflozin is effective for improving MR in patients with HF with New York Heart Association functional class II or III, 35%≤ejection fraction<50%, and effective regurgitant orifice area of chronic functional MR >0.1 cm2 on baseline echocardiography. We randomly assigned 128 patients to receive either ertugliflozin or placebo in addition to guideline-directed medical therapy for HF. The primary end point was change in effective regurgitant orifice area of functional MR from baseline to the 12-month follow-up. Secondary end points included changes in regurgitant volume, left ventricular (LV) volume indices, left atrial volume index, LV global longitudinal strain, and NT-proBNP (N-terminal pro-B-type natriuretic peptide). RESULTS: The treatment groups were generally well-balanced with regard to baseline characteristics: mean age, 66±11 years; 61% men; 13% diabetes; 51% atrial fibrillation; 43% use of angiotensin receptor-neprilysin inhibitor; ejection fraction, 42±8%; and effective regurgitant orifice area, 0.20±0.12 cm2. The decrease in effective regurgitant orifice area was significantly greater in the ertugliflozin group than in the placebo group (-0.05±0.06 versus 0.03±0.12 cm2; P<0.001). Compared with placebo, ertugliflozin significantly reduced regurgitant volume by 11.2 mL (95% CI, -16.1 to -6.3; P=0.009), left atrial volume index by 6.0 mL/m2 (95% CI, -12.16 to 0.15; P=0.005), and LV global longitudinal strain by 1.44% (95% CI, -2.42% to -0.46%; P=0.004). There were no significant between-group differences regarding changes in LV volume indices, ejection fraction, or NT-proBNP levels. Serious adverse events occurred in one patient (1.6%) in the ertugliflozin group and 6 (9.2%) in the placebo group (P=0.12). CONCLUSIONS: Among patients with functional MR associated with HF, ertugliflozin significantly improved LV global longitudinal strain and left atrial remodeling, and reduced functional MR. Sodium-glucose cotransporter 2 inhibitors may be considered for patients with functional MR. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04231331.
Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Insuficiência Cardíaca , Insuficiência da Valva Mitral , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Insuficiência da Valva Mitral/tratamento farmacológico , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/fisiopatologia , Masculino , Feminino , Idoso , Método Duplo-Cego , Pessoa de Meia-Idade , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Volume Sistólico/efeitos dos fármacos , Resultado do Tratamento , Fragmentos de Peptídeos/sangue , Função Ventricular Esquerda/efeitos dos fármacos , Peptídeo Natriurético EncefálicoRESUMO
Valvular heart disease is a common cause of morbidity and mortality worldwide and has no effective medical therapy. Severe disease is managed with valve replacement procedures, which entail high health care-related costs and postprocedural morbidity and mortality. Robust ongoing research programs have elucidated many important molecular pathways contributing to primary valvular heart disease. However, there remain several key challenges inherent in translating research on valvular heart disease to viable molecular targets that can progress through the clinical trials pathway and effectively prevent or modify the course of these common conditions. In this scientific statement, we review the basic cellular structures of the human heart valves and discuss how these structures change in primary valvular heart disease. We focus on the most common primary valvular heart diseases, including calcific aortic stenosis, bicuspid aortic valves, mitral valve prolapse, and rheumatic heart disease, and outline the fundamental molecular discoveries contributing to each. We further outline potential therapeutic molecular targets for primary valvular heart disease and discuss key knowledge gaps that might serve as future research priorities.
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American Heart Association , Doenças das Valvas Cardíacas , Humanos , Doenças das Valvas Cardíacas/tratamento farmacológico , Doenças das Valvas Cardíacas/metabolismo , Estados Unidos , AnimaisRESUMO
This review discusses recent advancements in the field of valvular heart disease. Topics covered include recognition of the impact of atrial fibrillation on development and assessment of valvular disease, strategies for global prevention of rheumatic heart disease, understanding and management of secondary mitral regurgitation, the updated classification of bicuspid aortic valve disease, recognition of heightened cardiovascular risk associated with moderate aortic stenosis, and a growing armamentarium of transcatheter therapies.
Assuntos
Estenose da Valva Aórtica , Fibrilação Atrial , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Insuficiência da Valva Mitral , Humanos , Doenças das Valvas Cardíacas/terapia , Insuficiência da Valva Mitral/terapia , Estenose da Valva Aórtica/terapia , Doença da Válvula Aórtica Bicúspide/complicaçõesRESUMO
BACKGROUND: Cardiac valve disease is observed in 2.5% of the general population and 10% of the elderly people. Effective pharmacological treatments are currently not available, and patients with severe cardiac valve disease require surgery. PROX1 (prospero-related homeobox transcription factor 1) and FOXC2 (Forkhead box C2 transcription factor) are transcription factors that are required for the development of lymphatic and venous valves. We found that PROX1 and FOXC2 are expressed in a subset of valvular endothelial cells (VECs) that are located on the downstream (fibrosa) side of cardiac valves. Whether PROX1 and FOXC2 regulate cardiac valve development and disease is not known. METHODS: We used histology, electron microscopy, and echocardiography to investigate the structure and functioning of heart valves from Prox1ΔVEC mice in which Prox1 was conditionally deleted from VECs. Isolated valve endothelial cells and valve interstitial cells were used to identify the molecular mechanisms in vitro, which were tested in vivo by RNAScope, additional mouse models, and pharmacological approaches. The significance of our findings was tested by evaluation of human samples of mitral valve prolapse and aortic valve insufficiency. RESULTS: Histological analysis revealed that the aortic and mitral valves of Prox1ΔVEC mice become progressively thick and myxomatous. Echocardiography revealed that the aortic valves of Prox1ΔVEC mice are stenotic. FOXC2 was downregulated and PDGF-B (platelet-derived growth factor-B) was upregulated in the VECs of Prox1ΔVEC mice. Conditional knockdown of FOXC2 and conditional overexpression of PDGF-B in VECs recapitulated the phenotype of Prox1ΔVEC mice. PDGF-B was also increased in mice lacking FOXC2 and in human mitral valve prolapse and insufficient aortic valve samples. Pharmacological inhibition of PDGF-B signaling with imatinib partially ameliorated the valve defects of Prox1ΔVEC mice. CONCLUSIONS: PROX1 antagonizes PDGF-B signaling partially via FOXC2 to maintain the extracellular matrix composition and prevent myxomatous degeneration of cardiac valves.
Assuntos
Doenças das Valvas Cardíacas , Prolapso da Valva Mitral , Animais , Humanos , Camundongos , Células Endoteliais/metabolismo , Doenças das Valvas Cardíacas/genética , Doenças das Valvas Cardíacas/prevenção & controle , Doenças das Valvas Cardíacas/metabolismo , Valva Mitral/metabolismo , Prolapso da Valva Mitral/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismoRESUMO
BACKGROUND: Myxomatous valve disease (MVD) is the most common cause of mitral regurgitation, leading to impaired cardiac function and heart failure. MVD in a mouse model of Marfan syndrome includes valve leaflet thickening and progressive valve degeneration. However, the underlying mechanisms by which the disease progresses remain undefined. METHODS: Mice with Fibrillin 1 gene variant Fbn1C1039G/+ recapitulate histopathologic features of Marfan syndrome, and Wnt (Wingless-related integration site) signaling activity was detected in TCF/Lef-lacZ (T-cell factor/lymphoid enhancer factor-ß-galactosidase) reporter mice. Single-cell RNA sequencing was performed from mitral valves of wild-type and Fbn1C1039G/+ mice at 1 month of age. Inhibition of Wnt signaling was achieved by conditional induction of the secreted Wnt inhibitor Dkk1 (Dickkopf-1) expression in periostin-expressing valve interstitial cells of Periostin-Cre; tetO-Dkk1; R26rtTA; TCF/Lef-lacZ; Fbn1C1039G/+ mice. Dietary doxycycline was administered for 1 month beginning with MVD initiation (1-month-old) or MVD progression (2-month-old). Histological evaluation and immunofluorescence for ECM (extracellular matrix) and immune cells were performed. RESULTS: Wnt signaling is activated early in mitral valve disease progression, before immune cell infiltration in Fbn1C1039G/+ mice. Single-cell transcriptomics revealed similar mitral valve cell heterogeneity between wild-type and Fbn1C1039G/+ mice at 1 month of age. Wnt pathway genes were predominantly expressed in valve interstitial cells and valve endothelial cells of Fbn1C1039G/+ mice. Inhibition of Wnt signaling in Fbn1C1039G/+ mice at 1 month of age prevented the initiation of MVD as indicated by improved ECM remodeling and reduced valve leaflet thickness with decreased infiltrating macrophages. However, later, Wnt inhibition starting at 2 months did not prevent the progression of MVD. CONCLUSIONS: Wnt signaling is involved in the initiation of mitral valve abnormalities and inflammation but is not responsible for later-stage valve disease progression once it has been initiated. Thus, Wnt signaling contributes to MVD progression in a time-dependent manner and provides a promising therapeutic target for the early treatment of congenital MVD in Marfan syndrome.
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Modelos Animais de Doenças , Progressão da Doença , Fibrilina-1 , Valva Mitral , Via de Sinalização Wnt , Animais , Fibrilina-1/genética , Fibrilina-1/metabolismo , Valva Mitral/metabolismo , Valva Mitral/patologia , Valva Mitral/efeitos dos fármacos , Camundongos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos Transgênicos , Síndrome de Marfan/genética , Síndrome de Marfan/complicações , Síndrome de Marfan/metabolismo , Síndrome de Marfan/patologia , Insuficiência da Valva Mitral/patologia , Insuficiência da Valva Mitral/metabolismo , Insuficiência da Valva Mitral/prevenção & controle , Insuficiência da Valva Mitral/genética , Camundongos Endogâmicos C57BL , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Inflamação/genética , Masculino , Feminino , Moléculas de Adesão Celular , AdipocinasRESUMO
BACKGROUND: Mitral valve (MV) disease including myxomatous degeneration is the most common form of valvular heart disease with an age-dependent frequency. Genetic evidence indicates that mutations of the human transcription factor FOXC1 are associated with MV defects, including MV regurgitation. In this study, we sought to determine whether murine Foxc1 and its closely related factor, Foxc2, are required in valvular endothelial cells (VECs) for the maintenance of MV leaflets, including VEC junctions and the stratified trilaminar ECM (extracellular matrix). METHODS: Adult mice carrying tamoxifen-inducible, vascular endothelial cell (EC), and lymphatic EC-specific, compound Foxc1;Foxc2 mutations (ie, EC-Foxc-DKO and lymphatic EC-Foxc-DKO mice, respectively) were used to study the function of Foxc1 and Foxc2 in the maintenance of MVs. The EC and lymphatic EC mutations of Foxc1/c2 were induced at 7 to 8 weeks of age by tamoxifen treatment, and abnormalities in the MVs of these mutant mice were assessed via whole-mount immunostaining, immunohistochemistry/RNAscope, Movat pentachrome/Masson Trichrome staining, and Evans blue injection. RESULTS: EC deletions of Foxc1 and Foxc2 in mice resulted in abnormally extended and thicker MVs by causing defects in the regulation of ECM organization with increased proteoglycan and decreased collagen. Notably, reticular adherens junctions were found in VECs of control MV leaflets, and these reticular structures were severely disrupted in EC-Foxc-DKO mice. PROX1 (prospero homeobox protein 1), a key regulator in a subset of VECs on the fibrosa side of MVs, was downregulated in EC-Foxc1/c2 mutant VECs. Furthermore, we determined the precise location of lymphatic vessels in murine MVs, and these lymphatic vessels were aberrantly expanded and dysfunctional in EC-Foxc1/c2 mutant MVs. Lymphatic EC deletion of Foxc1/c2 also resulted in similar structural/ECM abnormalities as seen in EC-Foxc1/c2 mutant MVs. CONCLUSIONS: Our results indicate that Foxc1 and Foxc2 are required for maintaining the integrity of the MV, including VEC junctions, ECM organization, and lymphatic vessel formation/function to prevent myxomatous MV degeneration.
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Modelos Animais de Doenças , Células Endoteliais , Fatores de Transcrição Forkhead , Linfangiogênese , Vasos Linfáticos , Camundongos Knockout , Animais , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Valva Mitral/metabolismo , Valva Mitral/patologia , Mutação , Camundongos , Junções Intercelulares/metabolismo , Junções Intercelulares/patologia , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/genética , Fenótipo , Camundongos Endogâmicos C57BL , Prolapso da Valva Mitral/metabolismo , Prolapso da Valva Mitral/genética , Prolapso da Valva Mitral/patologia , Matriz Extracelular/metabolismo , Matriz Extracelular/patologiaRESUMO
BACKGROUND AND AIMS: Mitral valve surgery and, more recently, mitral transcatheter edge-to-edge repair (TEER) are the two treatments of severe mitral regurgitation in eligible patients. Clinical comparison of both therapies remains limited by the number of patients analysed. The objective of this study was to analyse the outcomes of mitral TEER vs. isolated mitral valve surgery at a nationwide level in France. METHODS: Based on the French administrative hospital discharge database, the study collected information for all consecutive patients treated for mitral regurgitation with isolated TEER or isolated mitral valve surgery between 2012 and 2022. Propensity score matching was used for the analysis of outcomes. RESULTS: A total of 57 030 patients were found in the database. After matching on baseline characteristics, 2160 patients were analysed in each arm. At 3-year follow-up, TEER was associated with significantly lower incidence of cardiovascular death (hazard ratio 0.685, 95% confidence interval 0.563-0.832; P = .0001), pacemaker implantation, and stroke. Non-cardiovascular death (hazard ratio 1.562, 95% confidence interval 1.238-1.971; P = .0002), recurrent pulmonary oedema, and cardiac arrest were more frequent after TEER. No significant differences between the two groups were observed regarding all-cause death (hazard ratio 0.967, 95% confidence interval 0.835-1.118; P = .65), endocarditis, major bleeding, atrial fibrillation, and myocardial infarction. CONCLUSIONS: Our results suggest that TEER for severe mitral regurgitation was associated with lower cardiovascular mortality than mitral surgery at long-term follow-up. Pacemaker implantation and stroke were less frequently observed after TEER.
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Fibrilação Atrial , Endocardite , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Acidente Vascular Cerebral , Humanos , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/cirurgia , Acidente Vascular Cerebral/epidemiologia , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Bases de Dados Factuais , Resultado do TratamentoRESUMO
BACKGROUND AND AIMS: Presentation, outcome, and management of females with degenerative mitral regurgitation (DMR) are undefined. We analysed sex-specific baseline clinical and echocardiographic characteristics at referral for DMR due to flail leaflets and subsequent management and outcomes. METHODS: In the Mitral Regurgitation International Database (MIDA) international registry, females were compared with males regarding presentation at referral, management, and outcome (survival/heart failure), under medical treatment, post-operatively, and encompassing all follow-up. RESULTS: At referral, females (n = 650) vs. males (n = 1660) were older with more severe symptoms and higher MIDA score. Smaller cavity diameters belied higher cardiac dimension indexed to body surface area. Under conservative management, excess mortality vs. expected was observed in males [standardized mortality ratio (SMR) 1.45 (1.27-1.65), P < .001] but was higher in females [SMR 2.00 (1.67-2.38), P < .001]. Female sex was independently associated with mortality [adjusted hazard ratio (HR) 1.29 (1.04-1.61), P = .02], cardiovascular mortality [adjusted HR 1.58 (1.14-2.18), P = .007], and heart failure [adjusted HR 1.36 (1.02-1.81), P = .04] under medical management. Females vs. males were less offered surgical correction (72% vs. 80%, P < .001); however, surgical outcome, adjusted for more severe presentation in females, was similar (P ≥ .09). Ultimately, overall outcome throughout follow-up was worse in females who displayed persistent excess mortality vs. expected [SMR 1.31 (1.16-1.47), P < .001], whereas males enjoyed normal life expectancy restoration [SMR 0.92 (0.85-0.99), P = .036]. CONCLUSIONS: Females with severe DMR were referred to tertiary centers at a more advanced stage, incurred higher mortality and morbidity under conservative management, and were offered surgery less and later after referral. Ultimately, these sex-related differences yielded persistent excess mortality despite surgery in females with DMR, while males enjoyed restoration of life expectancy, warranting imperative re-evaluation of sex-specific DMR management.
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Insuficiência da Valva Mitral , Humanos , Feminino , Masculino , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/cirurgia , Idoso , Fatores Sexuais , Pessoa de Meia-Idade , Ecocardiografia , Sistema de Registros , Resultado do Tratamento , Tratamento Conservador , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/etiologia , Valva Mitral/cirurgia , Valva Mitral/diagnóstico por imagemRESUMO
BACKGROUND AND AIMS: Arrhythmic mitral valve prolapse (AMVP) is linked to life-threatening ventricular arrhythmias (VAs), and young women are considered at high risk. Cases of AMVP in women with malignant VA during pregnancy have emerged, but the arrhythmic risk during pregnancy is unknown. The authors aimed to describe features of women with high-risk AMVP who developed malignant VA during the perinatal period and to assess if pregnancy and the postpartum period were associated with a higher risk of malignant VA. METHODS: This retrospective international multi-centre case series included high-risk women with AMVP who experienced malignant VA and at least one pregnancy. Malignant VA included ventricular fibrillation, sustained ventricular tachycardia, or appropriate shock from an implantable cardioverter defibrillator. The authors compared the incidence of malignant VA in non-pregnant periods and perinatal period; the latter defined as occurring during pregnancy and within 6 months after delivery. RESULTS: The authors included 18 women with AMVP from 11 centres. During 7.5 (interquartile range 5.8-16.6) years of follow-up, 37 malignant VAs occurred, of which 18 were pregnancy related occurring in 13 (72%) unique patients. Pregnancy and 6 months after delivery showed increased incidence rate of malignant VA compared to the non-pregnancy period (univariate incidence rate ratio 2.66, 95% confidence interval 1.23-5.76). CONCLUSIONS: The perinatal period could impose increased risk of malignant VA in women with high-risk AMVP. The data may provide general guidance for pre-conception counselling and for nuanced shared decision-making between patients and clinicians.
Assuntos
Prolapso da Valva Mitral , Complicações Cardiovasculares na Gravidez , Humanos , Feminino , Gravidez , Prolapso da Valva Mitral/complicações , Prolapso da Valva Mitral/epidemiologia , Estudos Retrospectivos , Adulto , Complicações Cardiovasculares na Gravidez/epidemiologia , Fatores de Risco , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/etiologia , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/etiologia , Transtornos Puerperais/epidemiologia , Transtornos Puerperais/etiologia , Desfibriladores Implantáveis , Incidência , Fibrilação Ventricular/epidemiologia , Fibrilação Ventricular/etiologia , Período Pós-PartoRESUMO
BACKGROUND AND AIMS: Physical activity has proven effective in preventing atherosclerotic cardiovascular disease, but its role in preventing degenerative valvular heart disease (VHD) remains uncertain. This study aimed to explore the dose-response association between moderate to vigorous physical activity (MVPA) volume and the risk of degenerative VHD among middle-aged adults. METHODS: A full week of accelerometer-derived MVPA data from 87 248 UK Biobank participants (median age 63.3, female: 56.9%) between 2013 and 2015 were used for primary analysis. Questionnaire-derived MVPA data from 361 681 UK Biobank participants (median age 57.7, female: 52.7%) between 2006 and 2010 were used for secondary analysis. The primary outcome was the diagnosis of incident degenerative VHD, including aortic valve stenosis (AS), aortic valve regurgitation (AR), and mitral valve regurgitation (MR). The secondary outcome was VHD-related intervention or mortality. RESULTS: In the accelerometer-derived MVPA cohort, 555 incident AS, 201 incident AR, and 655 incident MR occurred during a median follow-up of 8.11 years. Increased MVPA volume showed a steady decline in AS risk and subsequent AS-related intervention or mortality risk, levelling off beyond approximately 300 min/week. In contrast, its association with AR or MR incidence was less apparent. The adjusted rates of AS incidence (95% confidence interval) across MVPA quartiles (Q1-Q4) were 11.60 (10.20, 13.20), 7.82 (6.63, 9.23), 5.74 (4.67, 7.08), and 5.91 (4.73, 7.39) per 10 000 person-years. The corresponding adjusted rates of AS-related intervention or mortality were 4.37 (3.52, 5.43), 2.81 (2.13, 3.71), 1.93 (1.36, 2.75), and 2.14 (1.50, 3.06) per 10 000 person-years, respectively. Aortic valve stenosis risk reduction was also observed with questionnaire-based MVPA data [adjusted absolute difference Q4 vs. Q1: AS incidence, -1.41 (-.67, -2.14) per 10 000 person-years; AS-related intervention or mortality, -.38 (-.04, -.88) per 10 000 person-years]. The beneficial association remained consistent in high-risk populations for AS, including patients with hypertension, obesity, dyslipidaemia, and chronic kidney disease. CONCLUSIONS: Higher MVPA volume was associated with a lower risk of developing AS and subsequent AS-related intervention or mortality. Future research needs to validate these findings in diverse populations with longer durations and repeated periods of activity monitoring.
RESUMO
BACKGROUND AND AIMS: Risk stratification for mitral valve transcatheter edge-to-edge repair (M-TEER) is paramount in the decision-making process to appropriately select patients with severe secondary mitral regurgitation (SMR). This study sought to develop and validate an artificial intelligence-derived risk score (EuroSMR score) to predict 1-year outcomes (survival or survival + clinical improvement) in patients with SMR undergoing M-TEER. METHODS: An artificial intelligence-derived risk score was developed from the EuroSMR cohort (4172 and 428 patients treated with M-TEER in the derivation and validation cohorts, respectively). The EuroSMR score was validated and compared with established risk models. RESULTS: The EuroSMR risk score, which is based on 18 clinical, echocardiographic, laboratory, and medication parameters, allowed for an improved discrimination of surviving and non-surviving patients (hazard ratio 4.3, 95% confidence interval 3.7-5.0; P < .001), and outperformed established risk scores in the validation cohort. Prediction for 1-year mortality (area under the curve: 0.789, 95% confidence interval 0.737-0.842) ranged from <5% to >70%, including the identification of an extreme-risk population (2.6% of the entire cohort), which had a very high probability for not surviving beyond 1 year (hazard ratio 6.5, 95% confidence interval 3.0-14; P < .001). The top 5% of patients with the highest EuroSMR risk scores showed event rates of 72.7% for mortality and 83.2% for mortality or lack of clinical improvement at 1-year follow-up. CONCLUSIONS: The EuroSMR risk score may allow for improved prognostication in heart failure patients with severe SMR, who are considered for a M-TEER procedure. The score is expected to facilitate the shared decision-making process with heart team members and patients.
Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Insuficiência da Valva Mitral/cirurgia , Inteligência Artificial , Coração , Ecocardiografia , Fatores de Risco , Resultado do TratamentoRESUMO
In mammals, odor information detected by olfactory sensory neurons is converted to a topographic map of activated glomeruli in the olfactory bulb. Mitral cells and tufted cells transmit signals sequentially to the olfactory cortex for behavioral outputs. To elicit innate behavioral responses, odor signals are directly transmitted by distinct subsets of mitral cells from particular functional domains in the olfactory bulb to specific amygdala nuclei. As for the learned decisions, input signals are conveyed by tufted cells as well as by mitral cells to the olfactory cortex. Behavioral scene cells link the odor information to the valence cells in the amygdala to elicit memory-based behavioral responses. Olfactory decision and perception take place in relation to the respiratory cycle. How is the sensory quality imposed on the olfactory inputs for behavioral outputs? How are the two types of odor signals, innate and learned, processed during respiration? Here, we review recent progress on the study of neural circuits involved in decision making in the mouse olfactory system.
Assuntos
Bulbo Olfatório/fisiologia , Córtex Olfatório/fisiologia , Olfato/fisiologia , Tonsila do Cerebelo/fisiologia , Animais , Humanos , Neurônios/fisiologiaRESUMO
Fragile X syndrome (FXS) is the single most common monogenetic cause of autism spectrum disorders (ASDs) in humans. FXS is caused by loss of expression of the fragile X mental retardation protein (FMRP), an mRNA-binding protein encoded on the X chromosome involved in suppressing protein translation. Sensory processing deficits have been a major focus of studies of FXS in both humans and rodent models of FXS, but olfactory deficits remain poorly understood. Here, we conducted experiments in wild-type (WT) and Fmr1 knock-out (KO; Fmr1-/y ) mice (males) that lack expression of the gene encoding FMRP to assess olfactory circuit and behavioral abnormalities. In patch-clamp recordings conducted in slices of the olfactory bulb, output mitral cells (MCs) in Fmr1 KO mice displayed greatly enhanced excitation under baseline conditions, as evidenced by a much higher rate of occurrence of spontaneous network-level events known as long-lasting depolarizations (LLDs). The higher probability of spontaneous LLDs (sLLDs), which appeared to be because of a decrease in GABAergic synaptic inhibition in glomeruli leading to more feedforward excitation, caused a reduction in the reliability of stimulation-evoked responses in MCs. In addition, in a go/no-go operant discrimination paradigm, we found that Fmr1 KO mice displayed impaired discrimination of odors in difficult tasks that involved odor mixtures but not altered discrimination of monomolecular odors. We suggest that the Fmr1 KO-induced reduction in MC response reliability is one plausible mechanism for the impaired fine odor discrimination.SIGNIFICANCE STATEMENT Fragile X syndrome (FXS) in humans is associated with a range of debilitating deficits including aberrant sensory processing. One sensory system that has received comparatively little attention in studies in animal models of FXS is olfaction. Here, we report the first comprehensive physiological analysis of circuit defects in the olfactory bulb in the commonly-used Fmr1 knock-out (KO) mouse model of FXS. Our studies indicate that Fmr1 KO alters the local excitation/inhibition balance in the bulb, similar to what Fmr1 KO does in other brain circuits, but through a novel mechanism that involves enhanced feedforward excitation. Furthermore, Fmr1 KO mice display behavioral impairments in fine odor discrimination, an effect that may be explained by changes in neural response reliability.
Assuntos
Síndrome do Cromossomo X Frágil , Bulbo Olfatório , Humanos , Masculino , Animais , Camundongos , Bulbo Olfatório/metabolismo , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Camundongos Knockout , Odorantes , Reprodutibilidade dos Testes , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Modelos Animais de DoençasRESUMO
Epicardial-derived cells (EPDCs) are involved in the regulation of myocardial growth and coronary vascularization and are critically important for proper development of the atrioventricular (AV) valves. SOX9 is a transcription factor expressed in a variety of epithelial and mesenchymal cells in the developing heart, including EPDCs. To determine the role of SOX9 in epicardial development, an epicardial-specific Sox9 knockout mouse model was generated. Deleting Sox9 from the epicardial cell lineage impairs the ability of EPDCs to invade both the ventricular myocardium and the developing AV valves. After birth, the mitral valves of these mice become myxomatous with associated abnormalities in extracellular matrix organization. This phenotype is reminiscent of that seen in humans with myxomatous mitral valve disease (MVD). An RNA-seq analysis was conducted in an effort to identify genes associated with this myxomatous degeneration. From this experiment, Cd109 was identified as a gene associated with myxomatous valve pathogenesis in this model. Cd109 has never been described in the context of heart development or valve disease. This study highlights the importance of SOX9 in the regulation of epicardial cell invasion-emphasizing the importance of EPDCs in regulating AV valve development and homeostasis-and reports a novel expression profile of Cd109, a gene with previously unknown relevance in heart development.
Assuntos
Doenças das Valvas Cardíacas , Valva Mitral , Humanos , Camundongos , Animais , Valva Mitral/metabolismo , Doenças das Valvas Cardíacas/patologia , Ventrículos do Coração/metabolismo , Miocárdio/metabolismo , Camundongos Knockout , Fatores de Transcrição/metabolismoRESUMO
In mammals, odour information within the olfactory bulb (OB) is processed by complex neural circuits before being ultimately represented in the action potential activity of mitral/tufted cells (M/Ts). Cholecystokinin-expressing (CCK+) superficial tufted cells (sTCs) are a subset of tufted cells that potentially contribute to olfactory processing in the OB by orchestrating M/T activity. However, the exact role of CCK+ sTCs in modulating odour processing and olfactory function in vivo is largely unknown. Here, we demonstrate that manipulating CCK+ sTCs can generate perception and induce place avoidance. Optogenetic activation/inactivation of CCK+ sTCs exerted strong but differing effects on spontaneous and odour-evoked M/T firing. Furthermore, inactivation of CCK+ sTCs disrupted M/T odour encoding and impaired olfactory detection and odour discrimination. These results establish the role of CCK+ sTCs in odour representation and olfactory behaviours. KEY POINTS: Mice could perceive the activity of CCK+ sTCs and show place avoidance to CCK+ sTC inactivation. Optical activation of CCK+ sTCs increased the percentage of cells with odour response but reduced the odour-evoked response in M/Ts in awake mice. Optical inactivation of CCK+ sTCs greatly decreased spontaneous firing and odour-evoked response in M/Ts. Inactivation of CCK+ sTCs impairs the odour decoding performance of M/Ts and disrupts odour detection and discrimination behaviours in mice. These results indicate that CCK+ sTCs participate in modulating the odour representation and maintaining normal olfactory-related behaviours.