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1.
Br J Haematol ; 192(5): 932-941, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33506990

RESUMO

Risk assessment for patients with sickle cell disease (SCD) remains challenging as it depends on an individual physician's experience and ability to integrate a variety of test results. We aimed to provide a new risk score that combines clinical, laboratory, and imaging data. In a prospective cohort of 600 adult patients with SCD, we assessed the relationship of 70 baseline covariates to all-cause mortality. Random survival forest and regularised Cox regression machine learning (ML) methods were used to select top predictors. Multivariable models and a risk score were developed and internally validated. Over a median follow-up of 4·3 years, 131 deaths were recorded. Multivariable models were developed using nine independent predictors of mortality: tricuspid regurgitant velocity, estimated right atrial pressure, mitral E velocity, left ventricular septal thickness, body mass index, blood urea nitrogen, alkaline phosphatase, heart rate and age. Our prognostic risk score had superior performance with a bias-corrected C-statistic of 0·763. Our model stratified patients into four groups with significantly different 4-year mortality rates (3%, 11%, 35% and 75% respectively). Using readily available variables from patients with SCD, we applied ML techniques to develop and validate a mortality risk scoring method that reflects the summation of cardiopulmonary, renal and liver end-organ damage. Trial Registration: ClinicalTrials.gov Identifier: NCT#00011648.


Assuntos
Anemia Falciforme/mortalidade , Fenótipo , Medição de Risco , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Anemia Falciforme/sangue , Nitrogênio da Ureia Sanguínea , Índice de Massa Corporal , Estudos de Casos e Controles , Análise por Conglomerados , Feminino , Seguimentos , Frequência Cardíaca , Valvas Cardíacas/fisiopatologia , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Adulto Jovem
2.
Br J Haematol ; 179(4): 648-656, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28880374

RESUMO

In sickle cell disease (SCD), abnormal microvascular function combined with chronic anaemia predisposes patients to perfusion-demand mismatch. We hypothesized that skeletal muscle and myocardial perfusion, normalized to the degree of anaemia, is reduced at basal-state compared to controls, and that this defect is ameliorated by hydroxycarbamide (HC; also termed hydroxyurea) therapy. Twenty-one SCD patients, of whom 15 were treated with HC, and 27 controls underwent contrast-enhanced ultrasound (CEU) perfusion imaging of the forearm as well as the myocardium. HC treatment was associated with lower white cell and reticulocyte counts, and higher fetal haemoglobin and total haemoglobin levels. When corrected for the degree of anaemia in SCD patients, skeletal flow in HC-treated patients was significantly higher than in untreated SCD patients (217·7 ± 125·4 vs. 85·9 ± 40·2, P = 0·018). Similarly, when normalized for both anaemia and increased myocardial work, resting myocardial perfusion was also significantly higher in HC-treated patients compared with untreated SCD patients (0·53 ± 0·47 vs. 0·13 ± 0·07, P = 0·028). Haemoglobin F (HbF) levels correlated with skeletal muscle microvascular flow (r = 0·55, P = 0·01). In conclusion, patients with SCD not on HC therapy have resting flow deficits in both skeletal muscle and myocardial flow. HC therapy normalizes flow and there is a direct correlation with HbF levels. Clinical trial registration ClinicalTrials.gov Identifier: NCT01602809; https://clinicaltrials.gov/ct2/show/NCT01602809?term=sACHDEV&rank=9.


Assuntos
Anemia Falciforme/tratamento farmacológico , Hidroxiureia/farmacologia , Microcirculação/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Adulto , Anemia Falciforme/fisiopatologia , Estudos de Casos e Controles , Circulação Coronária , Hemoglobina Fetal/análise , Humanos , Hidroxiureia/uso terapêutico , Pessoa de Meia-Idade , Esqueleto/irrigação sanguínea , Adulto Jovem
3.
Mol Genet Metab ; 121(4): 336-343, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28610912

RESUMO

BACKGROUND: Alström syndrome (AS) is a rare monogenetic disorder with multi-organ involvement. Complex metabolic disturbances are common and cardiomyopathy is a well-recognized feature in infants as well as in older children and adults. Although the mechanism of cardiomyopathy is not known, previous reports suggest that individuals with infantile-onset cardiac disease recover completely. METHODS: In this single center prospective series of 38 children and adults (age range 1.7 to 37.9years; 20 females) with AS, we evaluated cardiac manifestations in detail, in the context of specific ALMS1 mutations and multisystem involvement. All patients underwent ALMS1 sequencing, biochemical testing, electrocardiogram, and echocardiographic imaging with speckle tracking to evaluate systolic strain; 21 patients underwent cardiac magnetic resonance imaging with T1 mapping. RESULTS: Approximately half of patients (17/38) had a previous diagnosis of cardiomyopathy. Global longitudinal strain, a measure of systolic contractile function, was abnormal in 94% of patients and correlated with body mass index (r=0.602, p=0.002) and C-reactive protein level (r=0.56, p=0.004), but only in children. Electrocardiographic abnormalities were seen in two-thirds of patients, and left ventricular dilatation and/or dysfunction was present in 4 adults and 4 children. CONCLUSION: AS patients with a history of resolved infantile cardiomyopathy continue to have residual impairment in cardiac function. For patients with a normal ejection fraction and no prior cardiac history, strain can be abnormal, suggesting subclinical cardiac involvement. Close cardiac screening and aggressive modification of other manifestations of AS that are risk factors for cardiac disease, including obesity, inflammation, diabetes and dyslipidemia, are essential in caring for patients with AS.


Assuntos
Síndrome de Alstrom/fisiopatologia , Cardiomiopatias/fisiopatologia , Adolescente , Adulto , Síndrome de Alstrom/genética , Proteína C-Reativa/análise , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/genética , Proteínas de Ciclo Celular , Criança , Pré-Escolar , Ecocardiografia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Proteínas/genética , Fatores de Risco , Disfunção Ventricular Esquerda , Adulto Jovem
4.
bioRxiv ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38903100

RESUMO

Background: Septic shock, in humans and in our well-established animal model, is associated with increases in biventricular end diastolic volume (EDV) and decreases in ejection fraction (EF). These abnormalities occur over 2 days and reverse within 10 days. Septic non-survivors do not develop an increase in EDV. The mechanism for this cardiac dysfunction and EDV differences is unknown. Methods: Purpose-bred beagles randomized to receive intrabronchial Staphylococcus aureus (n=27) or saline (n=6) were provided standard ICU care including sedation, mechanical ventilation, and fluid resuscitation to a pulmonary arterial occlusion pressure of over 10mmHg. No catecholamines were administered. Over 96h, cardiac magnetic resonance imaging, echocardiograms, and invasive hemodynamics were serially performed, and laboratory data was collected. Tissue was obtained at 66h from six septic animals. Results: From 0-96h after bacterial challenge, septic animals vs. controls had significantly increased left ventricular wall edema (6%) and wall thinning with loss of mass (15%) which was more pronounced at 48h in non-survivors than survivors. On histology, edema was located predominantly in myocytes, the interstitium, and endothelial cells. Edema was associated with significantly worse biventricular function (lower EFs), ventricular-arterial coupling, and circumferential strain. In septic animals, from 0-24h, the EDV decreased from baseline and, despite cardiac filling pressures being similar, decreased significantly more in non-survivors. From 24-48h, all septic animals had increases in biventricular chamber sizes. Survivors biventricular EDVs were significantly greater than baseline and in non-survivors, where biventricular EDVs were not different from baseline. Preload, afterload, or HR differences did not explain these differential serial changes in chamber size. Conclusion: Systolic and diastolic cardiac dysfunction during sepsis is associated with ventricular wall edema. Rather than differences in preload, afterload, or heart rate, structural alterations to the ventricular wall best account for the volume changes associated with outcome during sepsis. In non-survivors, from 0-24h, sepsis induces a more severe diastolic dysfunction, further decreasing chamber size. The loss of left ventricular mass with wall thinning in septic survivors may, in part explain, the EDV increases from 24-48h. However, these changes continued and even accelerated into the recovery phase consistent with a reparative process rather than ongoing injury.

5.
Am J Physiol Endocrinol Metab ; 302(2): E218-25, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22045315

RESUMO

Insulin resistance is associated with endothelial dysfunction. Because African-American women are more insulin-resistant than white women, it is assumed that African-American women have impaired endothelial function. However, racial differences in postprandial endothelial function have not been examined. In this study, we test the hypothesis that African-American women have impaired postprandial endothelial function compared with white women. Postprandial endothelial function following a breakfast (20% protein, 40% fat, and 40% carbohydrate) was evaluated in 36 (18 African-American women, 18 white women) age- and body mass index (BMI)-matched (age: 37 ± 11 yr; BMI: 30 ± 6 kg/m(2)) women. Endothelial function, defined by percent change in brachial artery flow-mediated dilation (FMD), was measured at 0, 2, 4, and 6 h following a meal. There were no significant differences between the groups in baseline FMD, total body fat, abdominal visceral fat, and fasting levels of glucose, insulin, total cholesterol, low-density lipoprotein cholesterol, or serum estradiol. Although African-American women were less insulin-sensitive [insulin sensitivity index (mean ± SD): 3.6 ± 1.5 vs. 5.2 ± 2.6, P = 0.02], both fasting triglyceride (TG: 56 ± 37 vs. 97 ± 49 mg/dl, P = 0.007) and incremental TG area under the curve (AUC(0-6hr): 279 ± 190 vs. 492 ± 255 mg·dl(-1)·min(-1)·10(-2), P = 0.008) were lower in African-American than white women. Breakfast was associated with a significant increase in FMD in whites and African-Americans, and there was no significant difference in postprandial FMD between the groups (P > 0.1 for group × time interactions). Despite being insulin-resistant, postprandial endothelial function in African-American women was comparable to white women. These results imply that insulin sensitivity may not be an important determinant of racial differences in endothelial function.


Assuntos
Endotélio Vascular/fisiologia , Resistência à Insulina/etnologia , Período Pós-Prandial/fisiologia , Adulto , Negro ou Afro-Americano , Glicemia , Índice de Massa Corporal , Artéria Braquial/fisiologia , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Triglicerídeos/sangue , População Branca
6.
Haematologica ; 97(2): 193-200, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21993671

RESUMO

BACKGROUND: Patients with Chuvash polycythemia, (homozygosity for the R200W mutation in the von Hippel Lindau gene (VHL)), have elevated levels of hypoxia inducible factors HIF-1 and HIF-2, often become iron-deficient secondary to phlebotomy, and have elevated estimated pulmonary artery pressure by echocardiography. The objectives of this study were to provide a comprehensive echocardiographic assessment of cardiovascular physiology and to identify clinical, hematologic and cardiovascular risk factors for elevation of tricuspid regurgitation velocity in children and adults with Chuvash polycythemia. DESIGN AND METHODS: This cross-sectional observational study of 120 adult and pediatric VHL(R200W) homozygotes and 31 controls at outpatient facilities in Chuvashia, Russian Federation included echocardiography assessment of pulmonary artery pressure (tricuspid regurgitation velocity), cardiac volume, and systolic and diastolic function, as well as hematologic and clinical parameters. We determined the prevalence and risk factors for elevation of tricuspid regurgitation velocity in this population and its relationship to phlebotomy. RESULTS: The age-adjusted mean ± SE tricuspid regurgitation velocity was higher in VHL(R200W) homozygotes than controls with normal VHL alleles (2.5±0.03 vs. 2.3±0.05 m/sec, P=0.005). The age-adjusted left ventricular diastolic diameter (4.8±0.05 vs. 4.5±0.09 cm, P=0.005) and left atrial diameter (3.4±0.04 vs. 3.2±0.08 cm, P=0.011) were also greater in the VHL(R200W) homozygotes, consistent with increased blood volume, but the elevation in tricuspid regurgitation velocity persisted after adjustment for these variables. Among VHL(R200W) homozygotes, phlebotomy therapy was associated with lower serum ferritin concentration, and low ferritin independently predicted higher tricuspid regurgitation velocity (standardized beta=0.29; P=0.009). CONCLUSIONS: Children and adults with Chuvash polycythemia have higher estimated right ventricular systolic pressure, even after adjustment for echocardiography estimates of blood volume. Lower ferritin concentration, which is associated with phlebotomy, independently predicts higher tricuspid regurgitation velocity (www.clinicaltrials.gov identifier NCT00495638).


Assuntos
Anemia Ferropriva/genética , Hipóxia/genética , Policitemia/genética , Pressão Propulsora Pulmonar/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adolescente , Adulto , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/metabolismo , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Homozigoto , Humanos , Hipóxia/epidemiologia , Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Policitemia/epidemiologia , Policitemia/metabolismo , Federação Russa/epidemiologia , Insuficiência da Valva Tricúspide/epidemiologia , Insuficiência da Valva Tricúspide/genética , Insuficiência da Valva Tricúspide/metabolismo , Regulação para Cima/fisiologia , Função Ventricular Esquerda/fisiologia
7.
J Immunother Cancer ; 8(2)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32883871

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR) T-cell-associated cytokine release syndrome (CRS) may present with tachycardia, hemodynamic instability and reduced cardiac function. Pediatric CAR studies examining cardiac toxicity are limited. METHODS: We report on cardiac toxicity observed in children and young adults with hematologic malignancies enrolled in a CD19-28ζ CAR T-cell phase I trial (NCT01593696). All patients had a formal baseline echocardiogram. Real-time studies included echocardiograms on intensive care unit (ICU) transfer, and serial troponin and pro-B-type natriuretic peptide (pro-BNP) in the select patients. RESULTS: From July 2012 to March 2016, 52 patients, with a median age of 13.4 years (range 4.2-30.3) were treated. CRS developed in 37/52 (71%), which was grade 3-4 CRS in nine patients (17%). The median prior anthracycline exposure was 205 mg/m2 (range 70-620 mg/m2) in doxorubicin equivalents. The median baseline left ventricle ejection fraction (LVEF) and baseline LV global longitudinal strain (GLS) were 60% (range 50%-70%) and 16.8% (range 14.1%-23.5%, n=37) respectively. The majority, 78% (29/37), of patients had a reduced GLS <19% at baseline, and 6% (3/52) of patients had baseline LVEF <53%. ICU transfers occurred in 21 patients, with nine requiring vasoactive hemodynamic support and three necessitating >1 vasopressor. Six (12%) patients developed cardiac dysfunction (defined by >10% absolute decrease in LVEF or new-onset grade 2 or higher LV dysfunction, per CTCAE v4), among whom 4 had grade 3-4 CRS. Troponin elevations were seen in 4 of 13 patients, all of whom had low LVEF. Pro-BNP was elevated from baseline in 6/7 patients at the onset of CRS, with higher levels correlating with more severe CRS. Cardiac dysfunction fully resolved in all but two patients by day 28 post-CAR. CONCLUSION: Cardiac toxicity related to CD19-28ζ CAR T-cell-associated CRS was generally reversible by day 28 postinfusion. Implementation of more frequent monitoring with formal echocardiograms incorporating systemic analysis of changes in GLS, and cardiac biomarkers (troponin and proBNP) may help to earlier identify those patients at highest risk of severe cardiac systolic dysfunction, facilitating earlier interventions for CRS to potentially mitigate acute cardiac toxicity.


Assuntos
Síndrome da Liberação de Citocina/complicações , Cardiopatias/etiologia , Neoplasias Hematológicas/complicações , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Síndrome da Liberação de Citocina/patologia , Feminino , Cardiopatias/patologia , Humanos , Masculino , Adulto Jovem
8.
Echocardiography ; 26(10): 1153-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19725855

RESUMO

BACKGROUND: Little is known about the early mechanisms mediating left ventricular (LV) diastolic dysfunction in patients with hereditary hemochromatosis (HH). However, the increased oxidative stress related to iron overload may be involved in this process, and strain rate (SR), a sensitive echocardiography-derived measure of diastolic function, may detect such changes. AIM: we evaluated the relationship between left ventricular diastolic function measured with tissue Doppler SR and oxidative stress in asymptomatic HH subjects and control normal subjects. MATERIALS AND METHODS: Ninety-four consecutive visits of 43 HH subjects, age 30-74 (50 +/- 10, mean +/- SD), and 37 consecutive visits of 21 normal volunteers, age 30-63 (48 +/- 8), were evaluated over a 3-year period. SR was obtained from the basal septum in apical four-chamber views. All patients had confirmed C282Y homozygosity, a documented history of iron overload, and were New York Heart Association functional class I. Normal volunteers lacked HFE gene mutations causing HH. RESULTS: In the HH subjects, the SR demonstrated moderate but significant correlations with biomarkers of oxidative stress; however, no correlations were noted in normal subjects. The biomarkers of iron overload per se did not show significant correlations with the SR. CONCLUSION: Although our study was limited by the relatively small subject number, these results suggest that a possible role of oxidative stress to affect LV diastolic function in asymptomatic HH subjects and SR imaging may be a sensitive measure to detect that effect.


Assuntos
Hemocromatose/complicações , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Estresse Oxidativo/genética , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/genética , Adulto , Idoso , Técnicas de Imagem por Elasticidade , Feminino , Hemocromatose/diagnóstico , Proteína da Hemocromatose , Humanos , Masculino , Pessoa de Meia-Idade , Disfunção Ventricular Esquerda/diagnóstico
10.
Blood Adv ; 3(19): 2816-2824, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31578191

RESUMO

Cardiac complications have been well-described in sickle cell disease; however, it has been rare to see improvements in cardiac abnormalities following any interventions. Previous work has shown no significant structural changes after treatment with hydroxyurea. The cardiac effects of red blood cell exchange transfusion (RBCx) and hematopoietic stem cell transplantation (HSCT) have not been well described. We studied 56 patients undergoing HSCT (41 HLA-matched, 15 haploidentical), of whom 32 had RBCx within 3 months before HSCT. Echocardiograms and laboratory parameters were obtained at baseline, and at 3, 6, and 12 months following HSCT. Although hemolytic parameters and anemia improved following RBCx, there was a small increase in left ventricular volume index. Following successful HSCT, however, there were significant improvements in cardiac size, function, and diastolic filling parameters at 3 months followed by continued smaller improvements up to 1 year. There was a significant improvement in N-terminal pro B-type natriuretic peptide levels and a trend toward improvement in 6-minute walk time 1 year after HSCT. The magnitude of cardiac improvement seen following HSCT was comparable to that observed following correction of a volume overload state as seen in pregnancy or after repair of chronic valvular regurgitation. Further studies in sickle cell disease patients will help delineate which cardiac complications and what level of severity should be considered indications for HSCT.


Assuntos
Anemia Falciforme/terapia , Cardiomiopatias/etiologia , Cardiomiopatias/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Adulto , Feminino , Humanos , Masculino
11.
Blood Coagul Fibrinolysis ; 29(8): 701-707, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30300148

RESUMO

: Guidelines-recommend thrombolytic therapy for pulmonary embolism in patients with severe hemodynamic compromise and low risk of bleeding. Thrombolytics in submassive pulmonary embolism have an unfavorable risk/benefit ratio and remain controversial. Based on our experience with extensive, lower extremity thrombi, nine patients with symptomatic, submassive pulmonary embolisms (five medical, four surgical) were treated with low-dose alteplase (<10 mg/day, infused over 6 h per treatment). Alteplase was delivered by pulse spray and/or directed or undirected central venous catheters depending on clot size and location. All patients improved symptomatically and as determined objectively by pulmonary artery pressures and/or imaging, though acute benefits ranged from substantial to modest. One surgical patient required re-exploration for bleeding at the site of a recent retroperitoneal lymph node dissection. This experience may help guide the design of a randomized controlled trial to determine the safety and efficacy of low-dose alteplase for submassive pulmonary embolism.


Assuntos
Embolia Pulmonar/tratamento farmacológico , Ativador de Plasminogênio Tecidual/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/administração & dosagem , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Guias de Prática Clínica como Assunto , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/métodos , Resultado do Tratamento , Estados Unidos
12.
Am J Cardiol ; 98(7): 954-9, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16996882

RESUMO

Patients with hereditary hemochromatosis (HH) have been reported to develop diastolic functional abnormalities detectable by echocardiography, but it is unknown whether these occur in asymptomatic subjects. Thus, this study tested whether echocardiographic left ventricular (LV) relaxation abnormalities are detectable in subjects with asymptomatic HH. Forty-three asymptomatic subjects with HH (C282Y homozygosity in the HFE gene) and 21 age- and gender-matched control subjects without known HFE mutations underwent echocardiography with comprehensive diastolic functional evaluations. Subjects with HH were in New York Heart Association functional class I and consisted of 22 newly diagnosed patients (group A) and 21 chronically phlebotomized subjects with stable iron levels (group B). Group A subjects showed significant iron overload compared with group B subjects and controls (group C) (ferritin 1,164 +/- 886 [p <0.05 vs groups B and C], 128 +/- 262, and 98 +/- 76 microg/L and transferrin saturation 79 +/- 19% [p <0.05 vs groups B and C], 42 +/- 21%, and 26 +/- 10% for groups A, B, and C, respectively). Echocardiographic evaluation revealed (1) no statistically significant abnormalities of Doppler LV relaxation in HH groups; (2) significant augmentation of atrial contractile function in subjects with HH compared with controls, which was not correlated with iron levels and treatment status; and (3) the preservation of overall LV systolic function in HH groups. In conclusion, the results of this study suggest that the augmentation of atrial contraction appears to be an early detectable echocardiographic cardiac manifestation of abnormal diastolic function in asymptomatic subjects with HH, which may reflect undetectable subclinical LV relaxation abnormalities.


Assuntos
Função do Átrio Esquerdo/fisiologia , Átrios do Coração/fisiopatologia , Hemocromatose/genética , Hemocromatose/fisiopatologia , Contração Miocárdica/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos de Casos e Controles , Diástole/fisiologia , Ecocardiografia Doppler de Pulso , Feminino , Ferritinas/sangue , Átrios do Coração/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Transferrina/análise , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
13.
Am J Cardiol ; 98(5): 694-8, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16923464

RESUMO

There is no information available on left ventricular (LV) systolic function and the response to stress echocardiography in asymptomatic subjects with hereditary hemochromatosis (HH). To evaluate this topic, 43 asymptomatic subjects with HH homozygous for the C282Y HFE gene mutation (22 untreated subjects [group A] and 21 long-term treated subjects [group B]) were compared with 21 age- and gender-matched normal volunteers negative for HFE mutations. Contractile reserve, as a measure of LV systolic function, was assessed using continuous echocardiographic imaging and electrocardiography during supine bicycle exercise. Nineteen subjects in group A had repeat tests after 6 months of induction phlebotomy therapy to assess the effect of iron removal. Exercise performance and hemodynamic variables of supine bicycle exercise were comparable between subjects with HH and controls. LV contractile reserve of asymptomatic subjects with HH was not impaired at either a 75-W submaximal exercise level (mean +/- SD difference in ejection fraction from baseline 13.8 +/- 6.2%, 11.5 +/- 6.8%, and 13.4 +/- 7.8% in groups A, B, and C, respectively; p = NS for all by analysis of variance) or at peak exercise (difference in ejection fraction from baseline 18.9 +/- 6.9%, 18.4 +/- 7.8%, and 20.3 +/- 8.1% in groups A, B, and C, respectively; p = NS for all by analysis of variance). However, the incidence of abnormal ischemic stress electrocardiographic responses was more frequent in subjects with HH as a whole (33%) compared with normal subjects (10%). Stress imaging revealed no regional wall motion abnormalities, suggesting that these were false-positive results. Iron removal by induction phlebotomy did not affect stress echocardiographic performance. In conclusion, LV systolic function during exercise in asymptomatic subjects with HH is preserved, and 6-month induction phlebotomy does not affect stress echocardiographic performance.


Assuntos
Ecocardiografia sob Estresse , Hemocromatose/fisiopatologia , Função Ventricular Esquerda/fisiologia , Feminino , Seguimentos , Hemocromatose/diagnóstico por imagem , Hemocromatose/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Sístole
14.
Eur J Heart Fail ; 5(6): 751-7, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14675853

RESUMO

OBJECTIVE: To evaluate whether satellite cells injected into infarct areas in rabbits remain viable during 6 weeks follow-up and can improve cardiac function as assessed by echocardiography. METHODS: Myocardial infarction was induced in 16 New Zealand white rabbits, by ligation of the marginalis sinistra artery. Tissue from gluteus muscle biopsies was dissected into small pieces and cultured. Within 2-3 weeks the cells were expanded by 2-3 orders of magnitude and were fluorescent labeled. Single cell pellets for resuspension at >10(6)/1 ml were directly injected into the infarct areas in 8 rabbits. In 8 additional rabbits, 1 ml saline was injected (control). Regional left ventricular function was assessed weekly by 2-D echocardiography until animals were sacrificed. Analysis was performed blind and independently by two experienced echocardiographers, based on the American Society of Echocardiography scheme. RESULTS AND DISCUSSION: Six treated and five control rabbits completed the study. One week after the artery occlusion, left ventricular function scoring did not differ between groups, mean 8.7+/-1.6 vs 8.3+/-1.9 (P=0.74). At 6 weeks post-injection, echocardiographic score was significantly better in the treated group, mean 2.6+/-0.9 vs 6.9+/-2.1 (P=0.002). The treated group showed significant gradual segmental improvement between the first week up to week 6. After sacrifice, macro and microscopic transmural areas showed typical changes of myocardial infarction. Histochemical staining identified viable grafted cells in high density 6 weeks post-transplantation in all grafted hearts. CONCLUSION: Autologous satellite cells (skeletal myofiber), can be successfully grafted into rabbit hearts following myocardial infarction and may induce improved regional left ventricular function.


Assuntos
Infarto do Miocárdio/terapia , Células Satélites de Músculo Esquelético/transplante , Função Ventricular Esquerda/fisiologia , Animais , Técnicas de Cultura de Células , Ecocardiografia , Eletrocardiografia , Seguimentos , Coelhos , Resultado do Tratamento
15.
J Am Soc Echocardiogr ; 16(5): 403-8, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12724647

RESUMO

OBJECTIVES: The purpose of this study was quantitative evaluation of the inferobasal segment during dobutamine stress echocardiography using Doppler tissue imaging (DTI). BACKGROUND: Overdiagnosis of myocardial ischemia during dobutamine echocardiography is a common problem. DTI may permit more accurate quantitative diagnosis of ischemia. METHODS: A total of 50 patients with normal contraction of the inferobasal segment at rest were referred for dobutamine stress echocardiography. All underwent coronary angiography. Systolic and diastolic myocardial velocities were measured from apical 2-chamber view at rest and at the peak of dobutamine infusion. RESULTS: Stenosis of the right coronary artery >or= 70% was detected in 11 patients. Conventional stress echocardiography was falsely positive in 10.3% and falsely negative in 27.3%. When DTI was combined with conventional stress echocardiography, sensitivity and specificity was 81.8% and 97.4%, respectively. CONCLUSION: DTI may enhance the diagnosis of inferior ischemia during dobutamine echocardiography and can be added to conventional imaging in the treatment of these patients.


Assuntos
Ecocardiografia sob Estresse , Isquemia Miocárdica/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
16.
J Am Soc Echocardiogr ; 17(10): 1021-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15452466

RESUMO

OBJECTIVES: We sought to assess the feasibility of 2-dimensional strain, a novel software for real-time quantitative echocardiographic assessment of myocardial function. METHODS: Conventional and a novel non-Doppler-based echocardiography technique for advanced wall-motion analysis were performed in 20 patients with myocardial infarction and 10 healthy volunteers from the apical views. Two-dimensional strain is on the basis of the estimation that a discrete set of tissue velocities are present per each of many small elements on the ultrasound image. This software permits real-time assessment of myocardial velocities, strain, and strain rate. These parameters were also compared with Doppler tissue imaging measurements in 10 additional patients. RESULTS: In all, 80.3% of infarct and 97.8% of normal segments could be adequately tracked by the software. Peak systolic strain, strain rate, and peak systolic myocardial velocities, calculated from the software, were significantly higher in the normal than in the infarct segments. In the 10 additional patients, velocities, strain, and strain rate obtained with the novel software were not significantly different from those obtained with Doppler tissue imaging. CONCLUSION: Two-dimensional strain can accomplish real-time wall-motion analysis, and has the potential to become a standard for real-time automatic echocardiographic assessment of cardiac function.


Assuntos
Ecocardiografia/métodos , Infarto do Miocárdio/diagnóstico por imagem , Software , Adulto , Idoso , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Sístole , Fatores de Tempo , Disfunção Ventricular Esquerda/diagnóstico por imagem
18.
Am J Cardiol ; 108(12): 1796-800, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21925635

RESUMO

We have previously reported that left ventricular (LV) diastolic function in those with cardiac asymptomatic hereditary hemochromatosis (HH) is similar to that of volunteer control (VC) subjects, despite a presence of augmented left atrial contractile function. However, concern still exists that those with HH might gradually develop LV diastolic dysfunction despite receiving conventional phlebotomy treatment. To address this concern, we prospectively monitored the LV diastolic function of those with HH and VCs during a 5-year period. A total of 14 subjects with newly diagnosed HH (age 51 ± 12 years, 4 women, group A), 20 with chronic HH (age 51 ± 9 years, 7 women, group B), and 18 VCs (age 50 ± 8 years, 6 women, group C) successfully completed both the baseline evaluation of LV diastolic function, including tissue Doppler imaging, strain rate analysis with color-coded tissue Doppler, and the same studies repeated at 5 years of follow-up. All those with HH were New York Heart Association functional class I, were positive for the C282Y homozygote, and received conventional phlebotomy therapy. No VC had HH genetic mutations. The measures of LV diastolic function were comparable among the groups at 5 years of follow-up by analysis of variance. The echocardiographic measures of active left atrial contraction tended to decrease in the HH groups at 5 years of follow-up from baseline. In conclusion, LV diastolic function does not significantly deteriorate statistically during a 5-year period in subjects with cardiac asymptomatic HH after conventional phlebotomy treatment, regardless of their treatment history.


Assuntos
Hemocromatose/genética , Hemocromatose/fisiopatologia , Função Ventricular Esquerda , Diástole , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
20.
J Am Coll Cardiol ; 51(19): 1904-9, 2008 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-18466808

RESUMO

OBJECTIVES: Our goal was to determine the prevalence and characteristics of aortic valve disease in girls and women with monosomy for the X chromosome, or Turner syndrome (TS). BACKGROUND: Complications from congenital aortic valve disease are a major source of premature mortality in TS, but accurate data on the prevalence of aortic valve abnormalities and their association with aortic root dilation are not available. METHODS: This prospective study characterized the aortic valve and proximal aorta in 253 individuals with TS age 7 to 67 years using transthoracic echocardiography as our primary screening tool, supplemented with magnetic resonance imaging. RESULTS: Transthoracic echocardiography revealed a normal tricuspid aortic valve (TAV) in 172 and a bicuspid aortic valve (BAV) in 66 subjects. Transthoracic echocardiography could not visualize the aortic valve in 15 of 253 or 6%. Magnetic resonance imaging diagnosed 12 of 15 of these cases (8 BAV and 4 TAV), so that only 3 of 253 (1.2%) could not be visualized by either modality. The aortic valve was bicuspid in 74 of 250 (30%) adequately imaged subjects. The prevalence was equal in pediatric (<18 years, n = 89) and adult populations. Over 95% of abnormal aortic valves in TS resulted from fusion of the right and left coronary leaflets. Ascending aortic diameters were significantly greater at the annulus, sinuses, sinotubular junction, and ascending aorta in the BAV group, with aortic root dilation in 25% of subjects with BAV versus 5% of those with TAV. CONCLUSIONS: Girls and women with TS need focused screening of the aortic valve and root to identify the many asymptomatic individuals with abnormal valvular structure and/or aortic root dilation.


Assuntos
Insuficiência da Valva Aórtica/etiologia , Estenose da Valva Aórtica/etiologia , Valva Aórtica/patologia , Síndrome de Turner/complicações , Adolescente , Adulto , Idoso , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Superfície Corporal , Criança , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fenótipo , Prevalência , Estudos Prospectivos , Síndrome de Turner/diagnóstico por imagem , Síndrome de Turner/fisiopatologia , Ultrassonografia
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