Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Ann Neurol ; 93(4): 830-843, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36546684

RESUMO

OBJECTIVE: Recent evidence supports a link between increased TDP-43 burden and the presence of an APOE4 gene allele in Alzheimer's disease (AD); however, it is difficult to conclude the direct effect of APOE on TDP-43 pathology due to the presence of mixed AD pathologies. The goal of this study is to address how APOE isoforms impact TDP-43 pathology and related neurodegeneration in the absence of typical AD pathologies. METHODS: We overexpressed human TDP-43 via viral transduction in humanized APOE2, APOE3, APOE4 mice, and murine Apoe-knockout (Apoe-KO) mice. Behavior tests were performed across ages. Animals were harvested at 11 months of age and TDP-43 overexpression-related neurodegeneration and gliosis were assessed. To further address the human relevance, we analyzed the association of APOE with TDP-43 pathology in 160 postmortem brains from autopsy-confirmed amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with motor neuron disease (FTLD-MND) in the Mayo Clinic Brain Bank. RESULTS: We found that TDP-43 overexpression induced motor function deficits, neuronal loss, and gliosis in the motor cortex, especially in APOE2 mice, with much milder or absent effects in APOE3, APOE4, or Apoe-KO mice. In the motor cortex of the ALS and FTLD-MND postmortem human brains, we found that the APOE2 allele was associated with more severe TDP-43-positive dystrophic neurites. INTERPRETATION: Our data suggest a genotype-specific effect of APOE on TDP-43 proteinopathy and neurodegeneration in the absence of AD pathology, with the strongest association seen with APOE2. ANN NEUROL 2023;93:830-843.


Assuntos
Doença de Alzheimer , Esclerose Lateral Amiotrófica , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Doença dos Neurônios Motores , Humanos , Animais , Camundongos , Esclerose Lateral Amiotrófica/genética , Apolipoproteína E2/genética , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Apolipoproteína E3 , Gliose/genética , Proteínas de Ligação a DNA/genética , Apolipoproteínas E/genética , Degeneração Lobar Frontotemporal/patologia
2.
JAMA ; 329(7): 551-560, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36809323

RESUMO

Importance: Numerous studies have established the association of the common APOE ε2 and APOE ε4 alleles with Alzheimer disease (AD) risk across ancestries. Studies of the interaction of these alleles with other amino acid changes on APOE in non-European ancestries are lacking and may improve ancestry-specific risk prediction. Objective: To determine whether APOE amino acid changes specific to individuals of African ancestry modulate AD risk. Design, Setting, and Participants: Case-control study including 31 929 participants and using a sequenced discovery sample (Alzheimer Disease Sequencing Project; stage 1) followed by 2 microarray imputed data sets derived from the Alzheimer Disease Genetic Consortium (stage 2, internal replication) and the Million Veteran Program (stage 3, external validation). This study combined case-control, family-based, population-based, and longitudinal AD cohorts, which recruited participants (1991-2022) in primarily US-based studies with 1 US/Nigerian study. Across all stages, individuals included in this study were of African ancestry. Exposures: Two APOE missense variants (R145C and R150H) were assessed, stratified by APOE genotype. Main Outcomes and Measures: The primary outcome was AD case-control status, and secondary outcomes included age at AD onset. Results: Stage 1 included 2888 cases (median age, 77 [IQR, 71-83] years; 31.3% male) and 4957 controls (median age, 77 [IQR, 71-83] years; 28.0% male). In stage 2, across multiple cohorts, 1201 cases (median age, 75 [IQR, 69-81] years; 30.8% male) and 2744 controls (median age, 80 [IQR, 75-84] years; 31.4% male) were included. In stage 3, 733 cases (median age, 79.4 [IQR, 73.8-86.5] years; 97.0% male) and 19 406 controls (median age, 71.9 [IQR, 68.4-75.8] years; 94.5% male) were included. In ε3/ε4-stratified analyses of stage 1, R145C was present in 52 individuals with AD (4.8%) and 19 controls (1.5%); R145C was associated with an increased risk of AD (odds ratio [OR], 3.01; 95% CI, 1.87-4.85; P = 6.0 × 10-6) and was associated with a reported younger age at AD onset (ß, -5.87 years; 95% CI, -8.35 to -3.4 years; P = 3.4 × 10-6). Association with increased AD risk was replicated in stage 2 (R145C was present in 23 individuals with AD [4.7%] and 21 controls [2.7%]; OR, 2.20; 95% CI, 1.04-4.65; P = .04) and was concordant in stage 3 (R145C was present in 11 individuals with AD [3.8%] and 149 controls [2.7%]; OR, 1.90; 95% CI, 0.99-3.64; P = .051). Association with earlier AD onset was replicated in stage 2 (ß, -5.23 years; 95% CI, -9.58 to -0.87 years; P = .02) and stage 3 (ß, -10.15 years; 95% CI, -15.66 to -4.64 years; P = 4.0 × 10-4). No significant associations were observed in other APOE strata for R145C or in any APOE strata for R150H. Conclusions and Relevance: In this exploratory analysis, the APOE ε3[R145C] missense variant was associated with an increased risk of AD among individuals of African ancestry with the ε3/ε4 genotype. With additional external validation, these findings may inform AD genetic risk assessment in individuals of African ancestry.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , População Negra , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Alelos , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , População Negra/genética , Estudos de Casos e Controles , Genótipo , Fatores de Risco , Mutação de Sentido Incorreto
3.
Acta Neuropathol ; 143(6): 641-662, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35471463

RESUMO

Approximately half of Alzheimer's disease (AD) brains have concomitant Lewy pathology at autopsy, suggesting that α-synuclein (α-SYN) aggregation is a regulated event in the pathogenesis of AD. Genome-wide association studies revealed that the ε4 allele of the apolipoprotein E (APOE4) gene, the strongest genetic risk factor for AD, is also the most replicated genetic risk factor for Lewy body dementia (LBD), signifying an important role of APOE4 in both amyloid-ß (Aß) and α-SYN pathogenesis. How APOE4 modulates α-SYN aggregation in AD is unclear. In this study, we aimed to determine how α-SYN is associated with AD-related pathology and how APOE4 impacts α-SYN seeding and toxicity. We measured α-SYN levels and their association with other established AD-related markers in brain samples from autopsy-confirmed AD patients (N = 469), where 54% had concomitant LB pathology (AD + LB). We found significant correlations between the levels of α-SYN and those of Aß40, Aß42, tau and APOE, particularly in insoluble fractions of AD + LB. Using a real-time quaking-induced conversion (RT-QuIC) assay, we measured the seeding activity of soluble α-SYN and found that α-SYN seeding was exacerbated by APOE4 in the AD cohort, as well as a small cohort of autopsy-confirmed LBD brains with minimal Alzheimer type pathology. We further fractionated the soluble AD brain lysates by size exclusion chromatography (SEC) ran on fast protein liquid chromatography (FPLC) and identified the α-SYN species (~ 96 kDa) that showed the strongest seeding activity. Finally, using human induced pluripotent stem cell (iPSC)-derived neurons, we showed that amplified α-SYN aggregates from AD + LB brain of patients with APOE4 were highly toxic to neurons, whereas the same amount of α-SYN monomer was not toxic. Our findings suggest that the presence of LB pathology correlates with AD-related pathologies and that APOE4 exacerbates α-SYN seeding activity and neurotoxicity, providing mechanistic insight into how APOE4 affects α-SYN pathogenesis in AD.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Células-Tronco Pluripotentes Induzidas , Doença por Corpos de Lewy , Síndromes Neurotóxicas , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Apolipoproteínas E , Estudo de Associação Genômica Ampla , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Corpos de Lewy/patologia , Doença por Corpos de Lewy/patologia , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo
4.
Cardiol Young ; 27(2): 284-293, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27225323

RESUMO

BACKGROUND: Adults with tetralogy of Fallot experience atrial tachyarrhythmias; however, there are a few data on the outcomes of radiofrequency ablation. We examined the characteristics, outcome, and predictors of recurrence of atrial tachyarrhythmias after radiofrequency ablation in tetralogy of Fallot patients. Methods/results Retrospective data were collected from 2004 to 2013. In total, 56 ablations were performed on 37 patients. We identified two matched controls per case: patients with tetralogy of Fallot but no radiofrequency ablation and not known to have atrial tachyarrhythmias. Acute success was 98%. Left atrial arrhythmias increased in frequency over time. The mean follow-up was 41 months; 78% were arrhythmia-free. Number of cardiac surgeries, age, and presence of atrial fibrillation were predictors of recurrence. Lone cavo-tricuspid isthmus-dependent flutter reduced the likelihood of atrial fibrillation. Right and left atria in patients with tetralogy of Fallot were larger in ablated cases than controls. NYHA class was worse in cases and improved after ablation; baseline status predicted death. Of matched non-ablated controls, a number of them had atrial fibrillation. These patients were excluded from the case-control study but analysed separately. Most of them had died during follow-up, whereas of the matched ablated cases all were alive and the majority in sinus rhythm. CONCLUSION: Patients with tetralogy of Fallot and atrial tachyarrhythmias have more dilated atria than those without atrial tachyarrhythmias. Radiofrequency ablation improves functional status. Left atrial ablation is more commonly required with repeat procedures. There is a high prevalence of atrial tachyarrhythmias, particularly atrial fibrillation, in patients with tetralogy of Fallot; early radiofrequency ablation may have a protective effect against this.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/cirurgia , Tetralogia de Fallot/complicações , Adulto , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
5.
Europace ; 17(2): 274-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25371427

RESUMO

AIMS: The purpose of this study was to create an epicardial electroanatomic map of the right ventricle (RV) and then apply post-operative-targeted single- and dual-site RV temporary pacing with measurement of haemodynamic parameters. Cardiac resynchronization therapy is an established treatment for symptomatic left ventricular (LV) dysfunction. In congenital heart disease, RV dysfunction is a common cause of morbidity-little is known regarding the potential benefits of CRT in this setting. METHODS AND RESULTS: Sixteen adults (age = 32 ± 8 years; 6 M, 10 F) with right bundle branch block (RBBB) and repaired tetralogy of Fallot (n = 8) or corrected congenital pulmonary stenosis (n = 8) undergoing surgical pulmonary valve replacement (PVR) for pulmonary regurgitation underwent epicardial RV mapping and haemodynamic assessment of random pacing configurations including the site of latest RV activation. The pre-operative pulmonary regurgitant fraction was 49 ± 10%; mean LV end-diastolic volume (EDV) 85 ± 19 mL/min/m(2) and RVEDV 183 ± 89 mL/min/m(2) on cardiac magnetic resonance imaging. The mean pre-operative QRS duration is 136 ± 26 ms. The commonest site of latest activation was the RV free wall and DDD pacing here alone or combined with RV apical pacing resulted in significant increases in cardiac output (CO) vs. AAI pacing (P < 0.01 all measures). DDDRV alternative site pacing significantly improved CO by 16% vs. AAI (P = 0.018), and 8.5% vs. DDDRV apical pacing (P = 0.02). CONCLUSION: Single-site RV pacing targeted to the region of latest activation in patients with RBBB undergoing PVR induces acute improvements in haemodynamics and supports the concept of 'RV CRT'. Targeted pacing in such patients has therapeutic potential both post-operatively and in the long term.


Assuntos
Bloqueio de Ramo/terapia , Terapia de Ressincronização Cardíaca/métodos , Mapeamento Epicárdico , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Pulmonar/cirurgia , Adulto , Bloqueio de Ramo/complicações , Débito Cardíaco/fisiologia , Estimulação Cardíaca Artificial/métodos , Feminino , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Masculino , Insuficiência da Valva Pulmonar/complicações , Estenose da Valva Pulmonar/complicações , Estenose da Valva Pulmonar/congênito , Estenose da Valva Pulmonar/cirurgia , Volume Sistólico/fisiologia , Tetralogia de Fallot/complicações , Tetralogia de Fallot/cirurgia , Adulto Jovem
6.
Asia Pac J Oncol Nurs ; 11(8): 100544, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39148937

RESUMO

Objective: Patients undergoing surgery, particularly patients undergoing surgery for oncology diagnoses, experience anxiety. Surgery remains the primary treatment for many common types of cancer. One promising potential intervention to alleviate anxiety in the preoperative and postoperative period is meditation, an integrative medicine intervention. However, there remains a gap in the literature regarding the effectiveness of meditation to alleviate anxiety during the perioperative time period. Methods: The scoping review was conducted using the Arksey and O'Malley framework to synthesize the study findings and was reported with the Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). The review included EMBASE, PubMed, Web of Science, CINAHL Plus, Scopus, and Cochrane Review databases from 2013 through 2024. All identified articles were exported to the online systematic review software, Covidence. Results: A total of 538 initial citations were identified, 415 titles and abstracts were screened, and 83 full-text articles reviewed. Six studies were finally included. The data extracted from the literature included: study purpose, study design, sample size, preoperative or postoperative timeframe, instrument to evaluate anxiety, and conclusions. Conclusions: For patients undergoing oncology surgery, the perioperative period can be filled with anxiety. Guided, mindfulness, and loving-kindness meditation may be helpful in reducing anxiety, particularly in patients undergoing surgery for breast cancer during the postoperative period. However, the current literature is extremely limited. Future research should expand on the preliminary effectiveness to broader populations and carefully target the highest-risk populations for the ideal time point for interventions.

7.
Sci Adv ; 10(37): eadk3700, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39259788

RESUMO

Aggregated α-synuclein (α-SYN) proteins, encoded by the SNCA gene, are hallmarks of Lewy body disease (LBD), affecting multiple brain regions. However, the specific mechanisms underlying α-SYN pathology in cortical neurons, crucial for LBD-associated dementia, remain unclear. Here, we recapitulated α-SYN pathologies in human induced pluripotent stem cells (iPSCs)-derived cortical organoids generated from patients with LBD with SNCA gene triplication. Single-cell RNA sequencing, combined with functional and molecular validation, identified synaptic and mitochondrial dysfunction in excitatory neurons exhibiting high expression of the SNCA gene, aligning with observations in the cortex of autopsy-confirmed LBD human brains. Furthermore, we screened 1280 Food and Drug Administration-approved drugs and identified four candidates (entacapone, tolcapone, phenazopyridine hydrochloride, and zalcitabine) that inhibited α-SYN seeding activity in real-time quaking-induced conversion assays with human brains, reduced α-SYN aggregation, and alleviated mitochondrial dysfunction in SNCA triplication organoids and excitatory neurons. Our findings establish human cortical LBD models and suggest potential therapeutic drugs targeting α-SYN aggregation for LBD.


Assuntos
Células-Tronco Pluripotentes Induzidas , Doença por Corpos de Lewy , Organoides , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , Organoides/metabolismo , Organoides/efeitos dos fármacos , Organoides/patologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/citologia , Doença por Corpos de Lewy/patologia , Doença por Corpos de Lewy/genética , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/tratamento farmacológico , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos
8.
STAR Protoc ; 4(2): 102271, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37289593

RESUMO

The apolipoprotein E protein (apoE) confers differential risk for Alzheimer's disease depending on which isoforms are expressed. Here, we present a 2-day immunoprecipitation protocol using the HJ15.4 monoclonal apoE antibody for the pull-down of native apoE particles. We describe major steps for apoE production via immortalized astrocyte culture and HJ15.4 antibody bead coupling for apoE particle pull-down, elution, and characterization. This protocol could be used to isolate native apoE particles from multiple model systems or human biospecimens.

9.
Mol Neurodegener ; 16(1): 84, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930382

RESUMO

Transactive response DNA binding protein of 43 kDa (TDP-43) is an intranuclear protein encoded by the TARDBP gene that is involved in RNA splicing, trafficking, stabilization, and thus, the regulation of gene expression. Cytoplasmic inclusion bodies containing phosphorylated and truncated forms of TDP-43 are hallmarks of amyotrophic lateral sclerosis (ALS) and a subset of frontotemporal lobar degeneration (FTLD). Additionally, TDP-43 inclusions have been found in up to 57% of Alzheimer's disease (AD) cases, most often in a limbic distribution, with or without hippocampal sclerosis. In some cases, TDP-43 deposits are also found in neurons with neurofibrillary tangles. AD patients with TDP-43 pathology have increased severity of cognitive impairment compared to those without TDP-43 pathology. Furthermore, the most common genetic risk factor for AD, apolipoprotein E4 (APOE4), is associated with increased frequency of TDP-43 pathology. These findings provide strong evidence that TDP-43 pathology is an integral part of multiple neurodegenerative conditions, including AD. Here, we review the biology and pathobiology of TDP-43 with a focus on its role in AD. We emphasize the need for studies on the mechanisms that lead to TDP-43 pathology, especially in the setting of age-related disorders such as AD.


Assuntos
Doença de Alzheimer , Esclerose Lateral Amiotrófica , Proteínas de Ligação a DNA/metabolismo , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Doença de Alzheimer/metabolismo , Esclerose Lateral Amiotrófica/patologia , Demência Frontotemporal/patologia , Degeneração Lobar Frontotemporal/genética , Humanos , Emaranhados Neurofibrilares/metabolismo
11.
J Am Coll Cardiol ; 48(6): 1225-7, 2006 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-16979010

RESUMO

OBJECTIVES: This study was undertaken to assess the hematologic, clinical, and biochemical response to intravenous iron in patients with chronic heart failure (CHF) and anemia. BACKGROUND: Anemia is common in patients with CHF and is associated with higher morbidity and mortality. The combination of erythropoietin (EPO) and iron increases hemoglobin (Hb) and improves symptoms and exercise capacity in anemic CHF patients. It is not known whether intravenous iron alone is an effective treatment for anemia associated with CHF. METHODS: Sixteen anemic patients (Hb < or =12 g/dl) with stable CHF (age 68.3 +/- 11.5 years, 12 men, 9 participants New York Heart Association [NYHA] functional class II and the remainder class III, left ventricular ejection fraction 26 +/- 13%) received a maximum of 1 g of iron sucrose by bolus intravenous injections over a 12-day treatment phase in an outpatient setting. Mean follow-up was 92 +/- 6 days. RESULTS: Hemoglobin rose from 11.2 +/- 0.7 to 12.6 +/- 1.2 g/dl (p = 0.0007), Minnesota Living with Heart Failure (MLHF) score fell (denoting improvement) from 33 +/- 19 to 19 +/- 14 (p = 0.02), 6-min walk distance increased from 242 +/- 78 m to 286 +/- 72 m (p = 0.01), and all patients recorded NYHA class II at study end (p < 0.02). Changes in MLHF score and 6-min walk distance related closely to changes in Hb (r = 0.76, p = 0.002; r = 0.56, p = 0.03, respectively). Of all baseline measurements, only iron and transferrin saturation correlated with increases in Hb (r = 0.60, p = 0.02; r = 0.60, p = 0.01, respectively). There were no adverse events relating to drug administration or during follow-up. CONCLUSIONS: Intravenous iron sucrose, when used without concomitant EPO, is a simple and safe therapy that increases Hb, reduces symptoms, and improves exercise capacity in anemic patients with CHF. Further assessment of its efficacy should be made in a multicenter, randomized, placebo-controlled trial.


Assuntos
Anemia/tratamento farmacológico , Anemia/etiologia , Baixo Débito Cardíaco/complicações , Compostos Férricos/administração & dosagem , Idoso , Anemia/sangue , Anemia/fisiopatologia , Doença Crônica , Feminino , Compostos Férricos/uso terapêutico , Óxido de Ferro Sacarado , Gastroenteropatias/complicações , Ácido Glucárico , Hemoglobinas/metabolismo , Humanos , Injeções Intravenosas , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Resistência Física , Estudos Prospectivos , Transferrina/metabolismo , Caminhada
12.
Heart Lung Circ ; 13(4): 367-73, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16352219

RESUMO

OBJECTIVES: (1) To document, using tissue Doppler echocardiography (TDE), the regional variations in myocardial velocities (MV) in the left and right ventricles (LV and RV) in healthy young adults. (2) To determine the factors predicting MV. BACKGROUND: The pattern of tissue velocities within the right ventricle have yet to be determined and their patterns compared to the left ventricular velocities have not yet been described. METHODS: Forty healthy subjects, mean age 29+/-6 years, were studied using TDE. Left ventricular long-axis velocities (V(LV-LX)) were obtained by sampling from anteroseptal, anterior, lateral, posterior, inferior and inferoseptal LV walls, and long-axis RV velocities (V(RV-LX)) from the free wall of the RV, in standard apical views. LV radial velocities (V(LV-RAD)) and RV radial velocities (V(RV-RAD)) were assessed from the parasternal long and short-axis views. Regression analyses were performed to assess for correlations of MV with the variables: age, sex, QRS duration, heart rate, systolic and diastolic blood pressure, LV mass, width, LV or RV lengths, LA or RA areas. RESULTS: There were marked but consistent regional variations in systolic and diastolic tissue velocities in the LV and RV. Systolic (S') and early diastolic (E') velocities differed significantly around the left ventricular base, the highest velocities being located within the free wall at 6.4+/-2.2cm/s and 11.3+/-3.1cm/s, respectively. The E'/S'ratio remained constant and independent of position. V(LV-LX) were significantly higher than V(LV-RAD) (p<0.001). V(LV-LX)S' velocities were consistently lower than V(RV-LX)S' velocities (p<0.001). Age, heart rate, LV mass, width and length were significantly and independently associated with V(LV-LX)S' and V(LV-LX)E' values (p<0.01 for each). CONCLUSIONS: In healthy young adults, there is a consistent pattern of non-uniform MV throughout the heart, including differences in longitudinal and radial axis velocities both within the LV and between the LV and RV. Age, heart rate and LV structure are important determinants of MV. CONDENSED ABSTRACT: The patterns of left and right ventricular myocardial velocities and their relationships to each other are not well characterized. Furthermore, the determinants of myocardial velocities are not known. This study evaluated the myocardial longitudinal and radial axis tissue velocities in both the left (LV) and right (RV) ventricles and found that a consistent but non-uniform relationship exists between the LV and RV in both longitudinal and radial axes. Furthermore, age, heart rate and LV dimensions account for between 20% and 70% of the variability seen in LV systolic and diastolic velocities.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA