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1.
N Engl J Med ; 389(17): 1553-1565, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37888916

RESUMO

BACKGROUND: Transthyretin amyloidosis, also called ATTR amyloidosis, is associated with accumulation of ATTR amyloid deposits in the heart and commonly manifests as progressive cardiomyopathy. Patisiran, an RNA interference therapeutic agent, inhibits the production of hepatic transthyretin. METHODS: In this phase 3, double-blind, randomized trial, we assigned patients with hereditary, also known as variant, or wild-type ATTR cardiac amyloidosis, in a 1:1 ratio, to receive patisiran (0.3 mg per kilogram of body weight) or placebo once every 3 weeks for 12 months. A hierarchical procedure was used to test the primary and three secondary end points. The primary end point was the change from baseline in the distance covered on the 6-minute walk test at 12 months. The first secondary end point was the change from baseline to month 12 in the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS) score (with higher scores indicating better health status). The second secondary end point was a composite of death from any cause, cardiovascular events, and change from baseline in the 6-minute walk test distance over 12 months. The third secondary end point was a composite of death from any cause, hospitalizations for any cause, and urgent heart failure visits over 12 months. RESULTS: A total of 360 patients were randomly assigned to receive patisiran (181 patients) or placebo (179 patients). At month 12, the decline in the 6-minute walk distance was lower in the patisiran group than in the placebo group (Hodges-Lehmann estimate of median difference, 14.69 m; 95% confidence interval [CI], 0.69 to 28.69; P = 0.02); the KCCQ-OS score increased in the patisiran group and declined in the placebo group (least-squares mean difference, 3.7 points; 95% CI, 0.2 to 7.2; P = 0.04). Significant benefits were not observed for the second secondary end point. Infusion-related reactions, arthralgia, and muscle spasms occurred more often among patients in the patisiran group than among those in the placebo group. CONCLUSIONS: In this trial, administration of patisiran over a period of 12 months resulted in preserved functional capacity in patients with ATTR cardiac amyloidosis. (Funded by Alnylam Pharmaceuticals; APOLLO-B ClinicalTrials.gov number, NCT03997383.).


Assuntos
Amiloidose , Cardiomiopatias , Pré-Albumina , RNA Interferente Pequeno , Humanos , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Pré-Albumina/genética , Pré-Albumina/metabolismo , RNA Interferente Pequeno/uso terapêutico , Amiloidose Familiar/complicações , Amiloidose Familiar/tratamento farmacológico , Amiloidose Familiar/genética , Fígado/metabolismo , Método Duplo-Cego , Amiloidose/complicações , Amiloidose/tratamento farmacológico , Amiloidose/genética
2.
Curr Cardiol Rep ; 26(6): 635-641, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656586

RESUMO

PURPOSE OF REVIEW: More than a century since its discovery, the pathogenesis of Chagas heart disease (CHD) remains incompletely understood. The role of derangements in the autonomic control of the heart in triggering malignant arrhythmia before the appearance of contractile ventricular impairment was reviewed. RECENT FINDINGS: Although previous investigations had demonstrated the anatomical and functional consequences of parasympathetic dysautonomia upon the heart rate control, only recently, coronary microvascular disturbances and sympathetic denervation at the ventricular level have been reported in patients and experimental models of CHD, exploring with nuclear medicine methods their impact on the progression of myocardial dysfunction and cardiac arrhythmias. More important than parasympathetic impaired sinus node regulation, recent evidence indicates that myocardial sympathetic denervation associated with coronary microvascular derangements is causally related to myocardial injury and arrhythmia in CHD. Additionally, 123I-MIBG imaging is a promising tool for risk stratification of progression of ventricular dysfunction and sudden death.


Assuntos
Cardiomiopatia Chagásica , Simpatectomia , Humanos , Simpatectomia/métodos , Cardiomiopatia Chagásica/fisiopatologia , Cardiomiopatia Chagásica/cirurgia , Cardiomiopatia Chagásica/complicações , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Coração/inervação , Coração/diagnóstico por imagem , 3-Iodobenzilguanidina , Sistema Nervoso Simpático/fisiopatologia
3.
J Card Fail ; 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37648061

RESUMO

BACKGROUND: Heart failure (HF), a common cause of hospitalization, is associated with poor short-term clinical outcomes. Little is known about the long-term prognoses of patients with HF in Latin America. METHODS: BREATHE was the first nationwide prospective observational study in Brazil that included patients hospitalized due to acute heart failure (HF). Patients were included during 2 time periods: February 2011-December 2012 and June 2016-July 2018 SUGGESTION FOR REPHRASING: In-hospital management, 12-month clinical outcomes and adherence to evidence-based therapies were evaluated. RESULTS: A total of 3013 patients were enrolled at 71 centers in Brazil. At hospital admission, 83.8% had clear signs of pulmonary congestion. The main cause of decompensation was poor adherence to HF medications (27.8%). Among patients with reduced ejection fraction, concomitant use of beta-blockers, renin-angiotensin-aldosterone inhibitors and spironolactone decreased from 44.5% at hospital discharge to 35.2% at 3 months. The cumulative incidence of mortality at 12 months was 27.7%, with 24.3% readmission at 90 days and 44.4% at 12 months. CONCLUSIONS: In this large national prospective registry of patients hospitalized with acute HF, rates of mortality and readmission were higher than those reported globally. Poor adherence to evidence-based therapies was common at hospital discharge and at 12 months of follow-up.

4.
J Nucl Cardiol ; 30(6): 2327-2337, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37165114

RESUMO

BACKGROUND: Myocardial perfusion defect (MPD) is common in chronic Chagas cardiomyopathy (CCC) and is associated with inflammation and development of left ventricular systolic dysfunction. We tested the hypothesis that pentoxifylline (PTX) could reduce inflammation and prevent the development of MPD in a model of CCC in hamsters. METHODS AND RESULTS: We investigated with echocardiogram and rest myocardial perfusion scintigraphy at baseline (6-months after T. cruzi infection/saline) and post-treatment (after additional 2-months of PTX/saline administration), female Syrian hamsters assigned to 3 groups: T. cruzi-infected animals treated with PTX (CH + PTX) or saline (CH + SLN); and uninfected control animals (CO). At the baseline, all groups showed similar left ventricular ejection fraction (LVEF) and MPD areas. At post-treatment evaluation, there was a significant increase of MPD in CH + SLN group (0.8 ± 1.6 to 9.4 ± 9.7%), but not in CH + PTX (1.9 ± 3.0% to 2.7 ± 2.7%) that exhibited MPD area similar to CO (0.0 ± 0.0% to 0.0 ± 0.0%). The LVEF decreased in both infected groups. Histological analysis showed a reduced inflammatory infiltrate in CH + PTX group (395.7 ± 88.3 cell/mm2), as compared to CH + SLN (515.1 ± 133.0 cell/mm2), but larger than CO (193.0 ± 25.7 cell/mm2). The fibrosis and TNF-α expression was higher in both infected groups. CONCLUSIONS: The prolonged use of PTX is associated with positive effects, including prevention of MPD development and reduction of inflammation in the chronic hamster model of CCC.


Assuntos
Cardiomiopatia Chagásica , Doença de Chagas , Pentoxifilina , Cricetinae , Animais , Feminino , Cardiomiopatia Chagásica/diagnóstico por imagem , Pentoxifilina/farmacologia , Pentoxifilina/uso terapêutico , Volume Sistólico , Função Ventricular Esquerda , Tomografia Computadorizada por Raios X , Inflamação , Perfusão
5.
J Nucl Cardiol ; 29(6): 3166-3176, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34981413

RESUMO

BACKGROUND: Regional myocardial sympathetic denervation is a conspicuous and early disorder in patients with chronic Chagas' cardiomyopathy (CCC), potentially associated to the progression of myocardial dysfunction OBJECTIVE: To evaluate in a longitudinal study the association between the presence and the progression of regional myocardial sympathetic denervation with the deterioration of global and segmental left ventricular dysfunction in CCC. METHODS: 18 patients with CCC were submitted at initial evaluation and after 5.5 years to rest myocardial scintigraphy with 123Iodo-metaiodobenzylguanidine and 99mTc-sestamibi and to two-dimensional echocardiography to assess myocardial sympathetic denervation, extent of fibrosis, and the left ventricular ejection fraction (LVEF) and wall motion abnormalities. RESULTS: In the follow-up evaluation, compared to the initial one, we observed a significant decrease in LVEF (56 ± 11 to 49% ± 12; P = .01) and increased summed defects scores in the myocardial innervation scintigraphy (15 ± 10 to 20 ± 9; P < .01). The presence of regional myocardial sympathetic denervation in ventricular regions of viable non-fibrotic myocardium presented an odds ratio of 4.25 for the development of new wall motion abnormalities (P = .001). CONCLUSION: Regional and global myocardial sympathetic denervation is a progressive derangement in CCC. In addition, the regional denervation is topographically associated with areas of future development of regional systolic dysfunction in patients with CCC.


Assuntos
Cardiomiopatia Chagásica , Doença de Chagas , Disfunção Ventricular Esquerda , Humanos , Cardiomiopatia Chagásica/diagnóstico por imagem , Cardiomiopatia Chagásica/complicações , Volume Sistólico , Estudos Longitudinais , Função Ventricular Esquerda , Miocárdio , Simpatectomia , Doença de Chagas/complicações
6.
J Nucl Cardiol ; 27(2): 434-444, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-29696485

RESUMO

BACKGROUND: The relationship between microvasculopathy, autonomic denervation, and myocardial fibrosis, in Chagas cardiomyopathy is incompletely understood. The aim of this study was to explore the relative extent and anatomic distribution of myocardial hypoperfusion, autonomic denervation, and myocardial scarring using Single-Photon Emission Computerized Tomography (SPECT) imaging and Magnetic Resonance Imaging (MRI). METHODS: Thirteen patients with Chagas disease all had Iodine-123-metaiodobenzylguanidine (MIBG) SPECT, 99mTc-Sestamibi (MIBI) rest-stress SPECT, and gadolinium late enhancement MRI imaging within a 2-month interval. The anatomic location and extent of denervation, of stress-induced hypoperfusion and fibrosis, were assessed through image co-registration and quantification of abnormal tissue areas as a percent of total myocardium. RESULTS: The results showed a strong general anatomic concordance between areas of hypoperfusion, denervation, and fibrosis, suggesting that the three abnormal features may be correlated. Myocardial denervation was anatomically and quantitatively closely associated areas of stress hypoperfusion. CONCLUSION: Combined myocardial analysis of the extent and location of autonomic denervation, hypoperfusion, and scarring may allow for better understanding of the pathophysiology of Chagas cardiomyopathy. Autonomic myocardial denervation may be a more sensitive marker of cardiac involvement in Chagas Disease than finding by other imaging modalities.


Assuntos
Denervação Autônoma , Cardiomiopatia Chagásica/diagnóstico por imagem , Fibrose/patologia , Imageamento por Ressonância Magnética/métodos , Microcirculação , Miocárdio/patologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , 3-Iodobenzilguanidina , Adulto , Idoso , Sistema Nervoso Autônomo/cirurgia , Feminino , Coração , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio , Compostos Radiofarmacêuticos/farmacologia , Fatores de Risco , Tecnécio Tc 99m Sestamibi
7.
Eur Heart J ; 40(44): 3605-3612, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31424503

RESUMO

AIMS: Although loop diuretics are widely used to treat heart failure (HF), there is scarce contemporary data to guide diuretic adjustments in the outpatient setting. METHODS AND RESULTS: In a prospective, randomized and double-blind protocol, we tested the safety and tolerability of withdrawing low-dose furosemide in stable HF outpatients at 11 HF clinics in Brazil. The trial had two blindly adjudicated co-primary outcomes: (i) symptoms assessment quantified as the area under the curve (AUC) of a dyspnoea score on a visual-analogue scale evaluated at 4 time-points (baseline, Day 15, Day 45, and Day 90) and (ii) the proportion of patients maintained without diuretic reuse during follow-up. We enrolled 188 patients (25% females; 59 ± 13 years old; left ventricular ejection fraction = 32 ± 8%) that were randomized to furosemide withdrawal (n = 95) or maintenance (n = 93). For the first co-primary endpoint, no significant difference in patients' assessment of dyspnoea was observed in the comparison of furosemide withdrawal with continuous administration [median AUC 1875 (interquartile range, IQR 383-3360) and 1541 (IQR 474-3124), respectively; P = 0.94]. For the second co-primary endpoint, 70 patients (75.3%) in the withdrawal group and 77 patients (83.7%) in the maintenance group were free of furosemide reuse during follow-up (odds ratio for additional furosemide use with withdrawal 1.69, 95% confidence interval 0.82-3.49; P = 0.16). Heart failure-related events (hospitalizations, emergency room visits, and deaths) were infrequent and similar between groups (P = 1.0). CONCLUSIONS: Diuretic withdrawal did not result in neither increased self-perception of dyspnoea nor increased need of furosemide reuse. Diuretic discontinuation may deserve consideration in stable outpatients with no signs of fluid retention receiving optimal medical therapy. CLINICALTRIALS.GOV IDENTIFIER: NCT02689180.


Assuntos
Furosemida/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico , Suspensão de Tratamento/estatística & dados numéricos , Idoso , Líquidos Corporais/fisiologia , Brasil/epidemiologia , Estudos de Casos e Controles , Método Duplo-Cego , Dispneia/diagnóstico , Dispneia/psicologia , Feminino , Seguimentos , Furosemida/administração & dosagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Segurança , Autoimagem , Inibidores de Simportadores de Cloreto de Sódio e Potássio/administração & dosagem , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda/efeitos dos fármacos , Escala Visual Analógica
8.
Q J Nucl Med Mol Imaging ; 63(3): 302-310, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28299921

RESUMO

BACKGROUND: Patients with primary microvascular angina (PMA) commonly exhibit abnormal left ventricular function (LVF) during exercise, potentially owing to myocardial ischemia. Herein, we investigated in PMA patients the effect of the reduction of myocardial perfusion disorders, by using aerobic physical training, upon LVF response to exercise. METHODS: Overall, 15 patients (mean age, 53.7±8.9 years) with PMA and 15 healthy controls (mean age, 51.0±9.4 years) were studied. All subjects were subjected to baseline resting and exercise ventriculography, myocardial perfusion scintigraphy (MPS), and cardiopulmonary testing. PMA group members then participated in a 4-month physical training program and were reevaluated via the same methods applied at baseline. RESULTS: Baseline left ventricular ejection fraction (LVEF) determinations by ventriculography were similar for both groups (PMA, 67.7±10.2%; controls, 66.5±5.4%; P=0.67). However, a significant rise in LVEF seen in control subjects during exercise (75.3±6.2%; P=0.0001) did not materialize during peak exercise in patients with PMA (67.7±10.2%; P=0.47). Of the 12 patients in the PMA group who completed the training program, 10 showed a significant reduction in reversible perfusion defects during MPS. Nevertheless, LVEF at rest (63.5±8.7%) and at peak exercise (67.3±15.9%) did not differ significantly (P=0.30) in this subset. CONCLUSIONS: In patients with PMA, reduced left ventricular inotropic reserve observed during exercise did not normalize after improving myocardial perfusion through aerobic physical training.


Assuntos
Exercício Físico , Angina Microvascular/diagnóstico por imagem , Angina Microvascular/fisiopatologia , Imagem de Perfusão do Miocárdio , Função Ventricular Esquerda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ventriculografia com Radionuclídeos , Estudos Retrospectivos
9.
J Nucl Cardiol ; 26(5): 1569-1579, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-29392628

RESUMO

BACKGROUND: Myocardial perfusion defects (MPD) due to coronary microvascular dysfunction is frequent in chronic Chagas cardiomyopathy (CCC) and may be involved with development of myocardial damage. We investigated whether MPD precedes left ventricular systolic dysfunction and tested the hypothesis that prolonged use of dipyridamole (DIPY) could reduce MPD in an experimental model of CCC in hamsters. METHODS AND RESULTS: We investigated female hamsters 6-months after T. cruzi infection (baseline condition) and control animals, divided into T. cruzi-infected animals treated with DIPY (CH + DIPY) or placebo (CH + PLB); and uninfected animals treated with DIPY (CO + DIPY) or placebo (CO + PLB). The animals were submitted to echocardiogram and rest SPECT-Sestamibi-Tc99m myocardial perfusion scintigraphy. Next, the animals were treated with DIPY (4 mg/kg bid, intraperitoneal) or saline for 30 days, and reevaluated with the same imaging methods. At baseline, the CH + PLB and CH + DIPY groups showed larger areas of perfusion defect (13.2 ± 13.2% and 17.3 ± 13.2%, respectively) compared with CO + PLB and CO + DIPY (3.8 ± 2.2% e 3.5 ± 2.7%, respectively), P < .05. After treatment, we observed: reduction of perfusion defects only in the CH + DIPY group (17.3 ± 13.2% to 6.8 ± 7.6%, P = .001) and reduction of LVEF in CH + DIPY and CH + PLB groups (from 65.3 ± 9.0% to 53.6 ± 6.9% and from 69.3 ± 5.0% to 54.4 ± 8.6%, respectively, P < .001). Quantitative histology revealed greater extents of inflammation and interstitial fibrosis in both Chagas groups, compared with control group (P < .001), but no difference between Chagas groups (P > .05). CONCLUSIONS: The prolonged use of DIPY in this experimental model of CCC has reduced the rest myocardial perfusion defects, supporting the notion that those areas correspond to viable hypoperfused myocardium.


Assuntos
Cardiomiopatia Chagásica/diagnóstico por imagem , Cardiomiopatia Chagásica/tratamento farmacológico , Dipiridamol/administração & dosagem , Coração/diagnóstico por imagem , Animais , Cricetinae , Modelos Animais de Doenças , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Perfusão , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Trypanosoma cruzi , Vasodilatadores/administração & dosagem
10.
J Nucl Cardiol ; 25(1): 75-83, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27381340

RESUMO

BACKGROUND: To investigate the correlation between the extent of myocardial sympathetic denervation and fibrosis and the presence of degrees of severity of ventricular arrhythmias in chronic Chagas cardiomyopathy (CCC). METHODS: Forty-three CCC patients with left ventricular ejection fraction (LVEF) ≥ 35% were divided into three groups: SVT group-presenting Sustained Ventricular Tachycardia (SVT) (n = 15), NSVT group-exhibiting episodes of non-SVT (NSVT) on 24-h Holter monitoring (n = 11), and Control group-exhibiting neither SVT nor episodes of NSVT (n = 17). The patients underwent SPECT imaging for myocardial sympathetic innervation with 123Iodine-MIBG (MIBG) and myocardial perfusion with 99mTc-Sestamibi (MIBI) for the evaluation of regional myocardial fibrosis. RESULTS: The summed rest perfusion scores were similar in the three groups. The summed difference score between MIBG and MPI images, which evaluated the extent of denervated but viable myocardium, was significantly higher in SVT group (20.0 ± 8.0) as compared with the control group (2.0 ± 5.0, P < .0001) and with the NSVT group (11.0 ± 8.0, P < .05). CONCLUSIONS: The occurrence of ventricular arrhythmias of different degrees of severity correlates quantitatively with the extent of cardiac sympathetic denervation, but not with the extent of fibrosis, suggesting that myocardial sympathetic denervation plays a major role in triggering ventricular arrhythmia in CCC.


Assuntos
Arritmias Cardíacas/diagnóstico por imagem , Cardiomiopatia Chagásica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Simpatectomia , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Ecocardiografia , Eletrocardiografia , Feminino , Fibrose , Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Perfusão , Estudos Prospectivos , Índice de Gravidade de Doença , Sístole , Tecnécio Tc 99m Sestamibi
11.
Am Heart J ; 194: 125-131, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29223430

RESUMO

AIMS: Furosemide is commonly prescribed for symptom relief in heart failure (HF) patients. Although few data support the continuous use of loop diuretics in apparently euvolemic HF patients with mild symptoms, there is concern about safety of diuretic withdrawal in these patients. The ReBIC-1 trial was designed to evaluate the safety and tolerability of withdrawing furosemide in stable, euvolemic, chronic HF outpatients. This multicenter initiative is part of the Brazilian Research Network in Heart Failure (ReBIC) created to develop clinical studies in HF and composed predominantly by university tertiary care hospitals. METHODS: The ReBIC-1 trial is currently enrolling HF patients in NYHA functional class I-II, left ventricular ejection fraction ≤45%, without a HF-related hospital admission within the last 6 months, receiving a stable dose of furosemide (40 or 80 mg per day) for at least 6 months. Eligible patients will be randomized to maintain or withdraw furosemide in a double-blinded protocol. The trial has two co-primary outcomes: (1) dyspnea assessment using a visual-analogue scale evaluated at 4 time points and (2) the proportion of patients maintained without diuretics during the follow-up period. Total sample size was calculated to be 220 patients. Enrolled patients will be followed up to 90 days after randomization, and diuretic will be restarted if clinical deterioration or signs of congestion are detected. Pre-defined sub-group analysis based on NT-proBNP levels at baseline is planned. PERSPECTIVE: Evidence-based strategies aiming to simplify HF pharmacotherapy are needed in clinical practice. The ReBIC-1 trial will determine the safety of withdrawing furosemide in stable chronic HF patients.


Assuntos
Tolerância a Medicamentos , Furosemida/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Pacientes Ambulatoriais , Idoso , Biomarcadores/sangue , Deterioração Clínica , Diuréticos/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Resultado do Tratamento
12.
Inorg Chem ; 56(13): 7566-7573, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28613068

RESUMO

The estimation of the thermochemical radius is very important because most of the properties of the electrolyte solutions are, to some extent, linked to this property. Also, these thermochemical radii can be used to estimate lattice energies, which can be a very important parameter to be evaluated when assessing the possibility of synthesizing new inorganic materials. This study presents a formulation for estimating the thermochemical radii of complex ions. More specifically, these thermochemical radii are estimated using a weighted sum based on the radii of the contributing cations and anions. Also, the influence of the ionic charge on these thermochemical radii is assessed and discussed. Finally, the parameters obtained from the estimation of the thermochemical radii of complex cations are used to estimate cation volumes, and this estimation is then validated through comparison with literature values. As a result, the equations developed for thermochemical radii of complex ions produce predictions that are accurate to within 15% in general, whereas the equation developed to estimate cation volumes produces predictions that are accurate to within 20% considering cation volumes greater than 70 Å3.

13.
J Nucl Cardiol ; 22(1): 130-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25080872

RESUMO

BACKGROUND: Primary microvascular angina (PMA) is a common clinical condition associated to negative impact on quality of life (QOL) and reduced physical capacity. This study aimed at evaluating the effects of aerobic physical training (APT) on myocardial perfusion, physical capacity, and QOL in patients with PMA. METHODS: We investigated 12 patients (53.8 ± 9.7 years old; 7 women) with PMA, characterized by angina, angiographycally normal coronary arteries, and reversible perfusion defects (RPDs) detected on (99m)Tc-sestamibi-SPECT myocardial perfusion scintigraphy (MPS). At baseline and after 4 month of APT, the patients underwent MPS, cardiopulmonary test, and QOL questionnaire. Stress-rest MPS images were visually analyzed by attributing semi-quantitative scores (0 = normal; 4 = absent uptake), using a 17-segment left ventricular model. Summed stress, rest, and difference scores (SDS) were calculated. RESULTS: In comparison to the baseline, in the post-training we observed a significant increase in peak-VO2 (19.4 ± 4.8 and 22.1 ± 6.2 mL·kg(-1)·minute(-1), respectively, P = .01), reduction of SDS (10.1 ± 8.8 and 2.8 ± 4.9, P = .008), and improvement in QOL scores. CONCLUSIONS: Physical training in patients with PMA is associated with reduction of myocardial perfusion abnormalities, increasing of physical capacity, and improvement in QOL. The findings of this hypothesis-generating study suggest that APT can be a valid therapeutic option for patients with PMA.


Assuntos
Angina Microvascular/diagnóstico por imagem , Angina Microvascular/psicologia , Imagem de Perfusão do Miocárdio , Idoso , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Cintilografia , Compostos Radiofarmacêuticos , Inquéritos e Questionários , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem
14.
Menopause ; 31(5): 408-414, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38564706

RESUMO

OBJECTIVE: We investigated the systemic arterial hypertension effects on cardiovascular autonomic modulation and baroreflex sensitivity (BRS) in women with or without preserved ovarian function. METHODS: A total of 120 women were allocated into two groups: middle-aged premenopausal women (42 ± 3 y old; n = 60) and postmenopausal women (57 ± 4 y old; n = 60). Each group was also divided into two smaller groups (n = 30): normotensive and hypertensive. We evaluated hemodynamic and anthropometric parameters, cardiorespiratory fitness, BRS, heart rate variability (HRV), and blood pressure variability. The effects of hypertension and menopause were assessed using a two-way analysis of variance. Post hoc comparisons were performed using the Student-Newman-Keuls test. RESULTS: Comparing premenopausal groups, women with systemic arterial hypertension showed lower BRS (9.1 ± 4.4 vs 13.4 ± 4.2 ms/mm Hg, P < 0.001 ) and HRV total variance (1,451 ± 955 vs 2,483 ± 1,959 ms 2 , P = 0.005) values than normotensive; however, the vagal predominance still remained. On the other hand, both postmenopausal groups showed an expressive reduction in BRS (8.3 ± 4.2 vs 11.3 ± 4.8 ms/mm Hg, P < 0.001) and HRV characterized by sympathetic modulation predominance (low-frequency oscillations; 56% ± 17 vs 44% ± 17, P < 0.001), in addition to a significant increase in blood pressure variability variance (28.4 ± 14.9 vs 22.4 ± 12.5 mm Hg 2 , P = 0.015) compared with premenopausal groups. Comparing both postmenopausal groups, the hypertensive group had significantly lower values ​​of HRV total variance (635 ± 449 vs 2,053 ± 1,720 ms 2 , P < 0.001) and BRS (5.3 ± 2.8 vs 11.3 ± 3.2 ms/mm Hg) than the normotensive. CONCLUSIONS: Hypertensive middle-aged premenopausal women present HRV autonomic modulation impairment, but they still maintain a vagal predominance. After menopause, even normotensive women show sympathetic autonomic predominance, which may also be associated with aging. Furthermore, postmenopausal women with hypertension present even worse cardiac autonomic modulation.


Assuntos
Sistema Nervoso Autônomo , Barorreflexo , Pressão Sanguínea , Frequência Cardíaca , Hipertensão , Menopausa , Pós-Menopausa , Pré-Menopausa , Humanos , Feminino , Pessoa de Meia-Idade , Hipertensão/fisiopatologia , Adulto , Barorreflexo/fisiologia , Frequência Cardíaca/fisiologia , Sistema Nervoso Autônomo/fisiopatologia , Sistema Nervoso Autônomo/fisiologia , Pressão Sanguínea/fisiologia , Menopausa/fisiologia , Pós-Menopausa/fisiologia , Pré-Menopausa/fisiologia , Sistema Cardiovascular/fisiopatologia , Aptidão Cardiorrespiratória/fisiologia
15.
PLoS One ; 19(2): e0278738, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359001

RESUMO

OBJECTIVES: To identify and describe the profile of potential transthyretin cardiac amyloidosis (ATTR-CM) cases in the Brazilian public health system (SUS), using a predictive machine learning (ML) model. METHODS: This was a retrospective descriptive database study that aimed to estimate the frequency of potential ATTR-CM cases in the Brazilian public health system using a supervised ML model, from January 2015 to December 2021. To build the model, a list of ICD-10 codes and procedures potentially related with ATTR-CM was created based on literature review and validated by experts. RESULTS: From 2015 to 2021, the ML model classified 262 hereditary ATTR-CM (hATTR-CM) and 1,581 wild-type ATTR-CM (wtATTR-CM) potential cases. Overall, the median age of hATTR-CM and wtATTR-CM patients was 66.8 and 59.9 years, respectively. The ICD-10 codes most presented as hATTR-CM and wtATTR-CM were related to heart failure and arrythmias. Regarding the therapeutic itinerary, 13% and 5% of hATTR-CM and wtATTR-CM received treatment with tafamidis meglumine, respectively, while 0% and 29% of hATTR-CM and wtATTR-CM were referred to heart transplant. CONCLUSION: Our findings may be useful to support the development of health guidelines and policies to improve diagnosis, treatment, and to cover unmet medical needs of patients with ATTR-CM in Brazil.


Assuntos
Neuropatias Amiloides Familiares , Amiloidose , Cardiomiopatias , Humanos , Brasil/epidemiologia , Pré-Albumina , Saúde Pública , Estudos Retrospectivos , Aprendizado de Máquina , Cardiomiopatias/diagnóstico , Cardiomiopatias/epidemiologia , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/epidemiologia
16.
JAMA Cardiol ; 9(2): 105-113, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38055237

RESUMO

Importance: Readmissions after an index heart failure (HF) hospitalization are a major contemporary health care problem. Objective: To evaluate the feasibility and efficacy of an intensive telemonitoring strategy in the vulnerable period after an HF hospitalization. Design, Setting, and Participants: This randomized clinical trial was conducted in 30 HF clinics in Brazil. Patients with left ventricular ejection fraction less than 40% and access to mobile phones were enrolled up to 30 days after an HF admission. Data were collected from July 2019 to July 2022. Intervention: Participants were randomly assigned to a telemonitoring strategy or standard care. The telemonitoring group received 4 daily short message service text messages to optimize self-care, active engagement, and early intervention. Red flags based on feedback messages triggered automatic diuretic adjustment and/or a telephone call from the health care team. Main Outcomes and Measures: The primary end point was change in N-terminal pro-brain natriuretic peptide (NT-proBNP) from baseline to 180 days. A hierarchical win-ratio analysis incorporating blindly adjudicated clinical events (cardiovascular deaths and HF hospitalization) and variation in NT-proBNP was also performed. Results: Of 699 included patients, 460 (65.8%) were male, and the mean (SD) age was 61.2 (14.5) years. A total of 352 patients were randomly assigned to the telemonitoring strategy and 347 to standard care. Satisfaction with the telemonitoring strategy was excellent (net promoting score at 180 days, 78.5). HF self-care increased significantly in the telemonitoring group compared with the standard care group (score difference at 30 days, -2.21; 95% CI, -3.67 to -0.74; P = .001; score difference at 180 days, -2.08; 95% CI, -3.59 to -0.57; P = .004). Variation of NT-proBNP was similar in the telemonitoring group compared with the standard care group (telemonitoring: baseline, 2593 pg/mL; 95% CI, 2314-2923; 180 days, 1313 pg/mL; 95% CI, 1117-1543; standard care: baseline, 2396 pg/mL; 95% CI, 2122-2721; 180 days, 1319 pg/mL; 95% CI, 1114-1564; ratio of change, 0.92; 95% CI, 0.77-1.11; P = .39). Hierarchical analysis of the composite outcome demonstrated a similar number of wins in both groups (telemonitoring, 49 883 of 122 144 comparisons [40.8%]; standard care, 48 034 of 122 144 comparisons [39.3%]; win ratio, 1.04; 95% CI, 0.86-1.26). Conclusions and Relevance: An intensive telemonitoring strategy applied in the vulnerable period after an HF admission was feasible, well-accepted, and increased scores of HF self-care but did not translate to reductions in NT-proBNP levels nor improvement in a composite hierarchical clinical outcome. Trial Registration: ClinicalTrials.gov Identifier: NCT04062461.


Assuntos
Insuficiência Cardíaca , Envio de Mensagens de Texto , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Volume Sistólico , Função Ventricular Esquerda , Insuficiência Cardíaca/terapia , Hospitalização
17.
Expert Rev Cardiovasc Ther ; 21(6): 379-387, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37198947

RESUMO

INTRODUCTION: Myocardial ischemia is common in patients with chronic Chagas cardiomyopathy (CCC), but only recently clinical and experimental studies highlighted the involvement of this abnormality as contributing to the progression of myocardial damage. AREAS COVERED: Despite the absence of obstructive epicardial coronary artery disease at angiography, and limited evidence of abnormal flow regulation at the macrovascular level, remarkable functional and structural microvascular abnormalities are consistently reported by independent investigations of CCC. These derangements occur early and contribute to myocardial dysfunction. Recent research focused on reversing microvascular dysfunction as a target to positively impact the course of CCC. We conducted an extensive review of the scientific literature, aiming to summarize the role of coronary dysfunction causing myocardial ischemia in CCC, with a focus on implications for clinical management of individuals affected by this disease. EXPERT OPINION: Preclinical studies showed a clear correlation between perfusion defects and inflammation in viable but impaired dysfunctional myocardium. These findings provided further insight into the CCC complex pathophysiology and support the role of very few recent therapeutic interventions aiming to relieve myocardial ischemia. Further research is warranted to assess the efficacy of new interventions addressing reversal of microvascular ischemia and inflammation modulation and halting ventricular dysfunction progression in CCC.


Assuntos
Cardiomiopatias , Cardiomiopatia Chagásica , Doença de Chagas , Doença da Artéria Coronariana , Isquemia Miocárdica , Humanos , Isquemia Miocárdica/etiologia , Doença de Chagas/complicações , Inflamação , Vasos Coronários
18.
Cardiovasc Ultrasound ; 10: 40, 2012 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-23046747

RESUMO

UNLABELLED: In the clinical setting, the early detection of myocardial injury induced by doxorubicin (DXR) is still considered a challenge. To assess whether ultrasonic tissue characterization (UTC) can identify early DXR-related myocardial lesions and their correlation with collagen myocardial percentages, we studied 60 rats at basal status and prospectively after 2 mg/Kg/week DXR endovenous infusion. Echocardiographic examinations were conducted at baseline and at 8, 10, 12, 14 and 16 mg/Kg DXR cumulative dose. The left ventricle ejection fraction (LVEF), shortening fraction (SF), and the UTC indices: corrected coefficient of integrated backscatter (IBS) (tissue IBS intensity/ phantom IBS intensity) (CC-IBS) and the cyclic variation magnitude of this intensity curve (MCV) were measured. The variation of each parameter of study through DXR dose was expressed by the average and standard error at specific DXR dosages and those at baseline. The collagen percent (%) was calculated in six control group animals and 24 DXR group animals. CC-IBS increased (1.29±0.27 x 1.1±0.26-basal; p=0.005) and MCV decreased (9.1± 2.8 x 11.02±2.6-basal; p=0.006) from 8 mg/Kg to 16 mg/Kg DXR. LVEF presented only a slight but significant decrease (80.4±6.9% x 85.3±6.9%-basal, p=0.005) from 8 mg/Kg to 16 mg/Kg DXR. CC-IBS was 72.2% sensitive and 83.3% specific to detect collagen deposition of 4.24% (AUC=0.76). LVEF was not accurate to detect initial collagen deposition (AUC=0.54). IN CONCLUSION: UTC was able to early identify the DXR myocardial lesion when compared to LVEF, showing good accuracy to detect the initial collagen deposition in this experimental animal model.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Doxorrubicina/efeitos adversos , Cardiopatias/induzido quimicamente , Cardiopatias/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Diagnóstico Precoce , Masculino , Ratos , Ratos Wistar , Sensibilidade e Especificidade , Ultrassonografia , Função Ventricular Esquerda
19.
Int J Cardiovasc Imaging ; 38(1): 117-129, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34535853

RESUMO

Speckle tracking echocardiography (STE) enables early diagnosis of myocardial damage by evaluating myocardial strain. We aimed to study sequential changes in structural and ventricular functional parameters during Chagas disease (CD) natural history in an animal model. 37 Syrian hamsters were inoculated intraperitoneally with Trypanosoma cruzi (Chagas) and 20 with saline (Control). Echocardiography was performed before the infection (baseline), at 1 month (acute phase), 4, 6, and 8 months (chronic phase) using Vevo 2100 (Fujifilm Inc.) ultrasound system. Left ventricular end-diastolic diameter, Left ventricular end-systolic diameter (LVESD), Left ventricular ejection fraction (LVEF), Global longitudinal (GLS), circumferential (GCS) and radial (GRS) strain were evaluated. Tricuspid annular plane systolic excursion (TAPSE) was used to assess right ventricular function. At 8 months, animals were euthanized and LV myocardial samples were analyzed for quantitation of inflammation and fibrosis. LVEF decreased over time in Chagas group and a difference from Control was detected at 6 months (p-value of groups#time interaction = 0.005). There was a pronounced decrease in GLS, GCS and TAPSE in Chagas group (p-value of groups#time interaction = 0.003 for GLS, < 0.001 for GCS and < 0.009 for TAPSE vs Control) since the first month. LVESD, LVEF and GLS were significantly correlated to the number of inflammatory cells (r = 0.41, p = 0.046; r = - 0.42, p = 0.042; r = 0.41, p = 0.047) but not to fibrosis. In the Syrian hamster model of CD STE parameters (GLS and GCS) showed an early decrease. Changes in LVEF, LVESD, and GLS were correlated to myocardial inflammation but not to fibrosis.


Assuntos
Doença de Chagas , Disfunção Ventricular Esquerda , Animais , Cricetinae , Modelos Animais , Valor Preditivo dos Testes , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda
20.
Artigo em Inglês | MEDLINE | ID: mdl-34378764

RESUMO

Chagas disease (CD) has been changing from an endemic Latino-American disease to a condition found outside endemic regions, due to migratory movements. Although often subclinical, its acute phase can be lethal. This study aimed to assess survival during the acute phase of CD and its relationship with ventricular function in an experimental model. To this end, 30 Syrian hamsters were inoculated with Trypanosoma cruzi (IG) and other 15 animals received saline solution (CG). Groups were monitored daily and submitted to echocardiography in two moments: before the challenge and 15 days post-infection. Left ventricular ejection fraction (LVEF) and global longitudinal myocardial strain (GLS) of the LV were measured. The IG was divided into groups of animals with and without clinical signs of disease. ANOVA for mixed models was used to compare ventricular function parameters. Survival analysis was studied using Kaplan-Meier curves and the log-rank test. The follow-up lasted 60 days. LVEF in IG was reduced through time (53.80 to 43.55%) compared to CG (57.86 to 59.73%) (p=0.002). There was also a reduction of GLS (-18.97% to -12.44%) in the IG compared to CG (p=0.012). Twelve animals from IG died compared to one animal from CG. Eleven out of the 12 animals from the IG group died before presenting with clinical signs of infection. Survival was reduced in the IG compared to CG over time (p=0.02). The reduced survival during the acute phase of this experimental model of Chagas disease was related to the significant reduction of LV function. The mortality rate in the IG was higher in the group presenting with clinical signs of infection.


Assuntos
Doença de Chagas , Disfunção Ventricular Esquerda , Animais , Cricetinae , Modelos Animais , Estudos Prospectivos , Volume Sistólico , Função Ventricular Esquerda
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