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BACKGROUND: The selective cardiac myosin activator omecamtiv mecarbil has been shown to improve cardiac function in patients with heart failure with a reduced ejection fraction. Its effect on cardiovascular outcomes is unknown. METHODS: We randomly assigned 8256 patients (inpatients and outpatients) with symptomatic chronic heart failure and an ejection fraction of 35% or less to receive omecamtiv mecarbil (using pharmacokinetic-guided doses of 25 mg, 37.5 mg, or 50 mg twice daily) or placebo, in addition to standard heart-failure therapy. The primary outcome was a composite of a first heart-failure event (hospitalization or urgent visit for heart failure) or death from cardiovascular causes. RESULTS: During a median of 21.8 months, a primary-outcome event occurred in 1523 of 4120 patients (37.0%) in the omecamtiv mecarbil group and in 1607 of 4112 patients (39.1%) in the placebo group (hazard ratio, 0.92; 95% confidence interval [CI], 0.86 to 0.99; P = 0.03). A total of 808 patients (19.6%) and 798 patients (19.4%), respectively, died from cardiovascular causes (hazard ratio, 1.01; 95% CI, 0.92 to 1.11). There was no significant difference between groups in the change from baseline on the Kansas City Cardiomyopathy Questionnaire total symptom score. At week 24, the change from baseline for the median N-terminal pro-B-type natriuretic peptide level was 10% lower in the omecamtiv mecarbil group than in the placebo group; the median cardiac troponin I level was 4 ng per liter higher. The frequency of cardiac ischemic and ventricular arrhythmia events was similar in the two groups. CONCLUSIONS: Among patients with heart failure and a reduced ejection, those who received omecamtiv mecarbil had a lower incidence of a composite of a heart-failure event or death from cardiovascular causes than those who received placebo. (Funded by Amgen and others; GALACTIC-HF ClinicalTrials.gov number, NCT02929329; EudraCT number, 2016-002299-28.).
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Miosinas Cardíacas/metabolismo , Cardiotónicos/uso terapéutico , Insuficiencia Cardíaca Sistólica/tratamiento farmacológico , Urea/análogos & derivados , Anciano , Anciano de 80 o más Años , Miosinas Cardíacas/efectos de los fármacos , Cardiotónicos/efectos adversos , Cardiotónicos/farmacología , Enfermedades Cardiovasculares/mortalidad , Femenino , Insuficiencia Cardíaca Sistólica/metabolismo , Insuficiencia Cardíaca Sistólica/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica/efectos de los fármacos , Volumen Sistólico , Urea/efectos adversos , Urea/farmacología , Urea/uso terapéuticoRESUMEN
BACKGROUND: Omecamtiv mecarbil improves outcomes in patients with heart failure and reduced ejection fraction (HFrEF). We examined the relationship between baseline troponin levels, change in troponin levels over time and the treatment effect of omecamtiv mecarbil in patients enrolled in the Global Approach to Lowering Adverse Cardiac Outcomes through Improving Contractility in Heart Failure (GALACTIC-HF) trial (NCT02929329). METHODS: GALACTIC-HF was a double-blind, placebo-controlled trial that randomized 8256 patients with symptomatic HFrEF to omecamtiv mecarbil or placebo. High-sensitivity troponin I (cTnI) was measured serially at a core laboratory. We analyzed the relationship between both baseline cTnI and change in cTnI concentrations with clinical outcomes and the treatment effect of omecamtiv mecarbil. RESULTS: Higher baseline cTnI concentrations were associated with a risk of adverse outcomes (hazard ratio for the primary endpoint of time to first HF event or CV deathâ¯=â¯1.30; 95% CI 1.28, 1.33; P < 0.001 per doubling of baseline cTnI). Although the incidence of safety outcomes was higher in patients with higher baseline cTnI, there was no difference between treatment groups. Treatment with omecamtiv mecarbil led to a modest increase in cTnI that was related to plasma concentrations of omecamtiv mecarbil, and it peaked at 6 weeks. An increase in troponin from baseline to week 6 was associated with an increased risk of the primary endpoint (P < 0.001), which was similar, regardless of treatment assignment (P value for interactionâ¯=â¯0.2). CONCLUSIONS: In a cohort of patients with HFrEF, baseline cTnI concentrations were strongly associated with adverse clinical outcomes. Although cTnI concentrations were higher in patients treated with omecamtiv mecarbil, we did not find a differential effect of omecamtiv mecarbil on either safety or efficacy based on baseline cTnI status or change in cTnI.
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Biomarcadores , Insuficiencia Cardíaca , Volumen Sistólico , Troponina I , Humanos , Masculino , Método Doble Ciego , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/sangre , Persona de Mediana Edad , Anciano , Troponina I/sangre , Resultado del Tratamiento , Volumen Sistólico/efectos de los fármacos , Biomarcadores/sangre , Urea/análogos & derivados , Urea/uso terapéutico , Urea/farmacología , Carbamatos/uso terapéuticoRESUMEN
PURPOSE: Patients with chronic chagasic cardiomyopathy with preserved ventricular function present with autonomic imbalance. This study evaluated the effects of exercise training (ET) in restoring peripheral and cardiac autonomic control and skeletal muscle phenotype in patients with subclinical chronic chagasic cardiomyopathy. METHODS: This controlled trial (NCT02295215) included 24 chronic chagasic cardiomyopathy patients who were randomized www.random.org/lists/ into two groups: those who underwent exercise training (n = 12) and those who continued their usual activities (n = 12). Eight patients completed the exercise training protocol, and 10 patients were clinically followed up for 4 months. Muscular sympathetic nerve activity was measured by microneurography and muscle blood flow (MBF) using venous occlusion plethysmography. The low-frequency component of heart rate variability in normalized units (LFnuHR) reflects sympathetic activity in the heart, and the low-frequency component of systolic blood pressure variability in normalized units reflects sympathetic activity in the vessels. The infusion of vasoactive drugs (phenylephrine and sodium nitroprusside) was used to evaluate cardiac baroreflex sensitivity, and a vastus lateralis muscle biopsy was performed to evaluate atrogin-1 and MuRF-1 gene expression. RESULTS: The baroreflex sensitivity for increases (p = 0.002) and decreases (p = 0.02) in systolic blood pressure increased in the ET group. Muscle blood flow also increased only in the ET group (p = 0.004). Only the ET group had reduced resting muscular sympathetic nerve activity levels (p = 0.008) and sympathetic activity in the heart (LFnu; p = 0.004) and vessels (p = 0.04) after 4 months. Regarding skeletal muscle, after 4 months, participants in the exercise training group presented with lower atrogin-1 gene expression than participants who continued their activities as usual (p = 0.001). The reduction in muscular sympathetic nerve activity was positively associated with reduced atrogin-1 (r = 0.86; p = 0.02) and MuRF-1 gene expression (r = 0.64; p = 0.06); it was negatively associated with improved baroreflex sensitivity both for increases (r = -0.72; p = 0.020) and decreases (r = -0.82; p = 0.001) in blood pressure. CONCLUSIONS: ET improved cardiac and peripheral autonomic function in patients with subclinical chagasic cardiomyopathy. ET reduced MSNA and sympathetic activity in the heart and vessels and increased cardiac parasympathetic tone and baroreflex sensitivity. Regarding peripheral muscle, after 4 months, patients who underwent exercise training had an increased cross-sectional area of type I fibers and oxidative metabolism of muscle fibers, and decreased atrogin-1 gene expression, compared to participants who continued their activities as usual. In addition, the reduction in MSNA was associated with improved cardiac baroreflex sensitivity, reduced sympathetic cardiovascular tone, and reduced atrogin-1 and MuRF-1 gene expression. TRIAL REGISTRATION: ID: NCT02295215. Registered in June 2013.
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Cardiomiopatía Chagásica , Sistema Nervioso Autónomo , Barorreflejo , Presión Sanguínea , Cardiomiopatía Chagásica/terapia , Ejercicio Físico , Frecuencia Cardíaca , Humanos , Músculo Esquelético , Sistema Nervioso SimpáticoRESUMEN
BACKGROUND: Clinical trials in heart failure have focused on the improvement in symptoms or decreases in the risk of death and other cardiovascular events. Little is known about the effect of drugs on the risk of clinical deterioration in surviving patients. METHODS AND RESULTS: We compared the angiotensin-neprilysin inhibitor LCZ696 (400 mg daily) with the angiotensin-converting enzyme inhibitor enalapril (20 mg daily) in 8399 patients with heart failure and reduced ejection fraction in a double-blind trial. The analyses focused on prespecified measures of nonfatal clinical deterioration. In comparison with the enalapril group, fewer LCZ696-treated patients required intensification of medical treatment for heart failure (520 versus 604; hazard ratio, 0.84; 95% confidence interval, 0.74-0.94; P=0.003) or an emergency department visit for worsening heart failure (hazard ratio, 0.66; 95% confidence interval, 0.52-0.85; P=0.001). The patients in the LCZ696 group had 23% fewer hospitalizations for worsening heart failure (851 versus 1079; P<0.001) and were less likely to require intensive care (768 versus 879; 18% rate reduction, P=0.005), to receive intravenous positive inotropic agents (31% risk reduction, P<0.001), and to have implantation of a heart failure device or cardiac transplantation (22% risk reduction, P=0.07). The reduction in heart failure hospitalization with LCZ696 was evident within the first 30 days after randomization. Worsening of symptom scores in surviving patients was consistently more common in the enalapril group. LCZ696 led to an early and sustained reduction in biomarkers of myocardial wall stress and injury (N-terminal pro-B-type natriuretic peptide and troponin) versus enalapril. CONCLUSIONS: Angiotensin-neprilysin inhibition prevents the clinical progression of surviving patients with heart failure more effectively than angiotensin-converting enzyme inhibition. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01035255.
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Aminobutiratos/uso terapéutico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Progresión de la Enfermedad , Enalapril/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Neprilisina/antagonistas & inhibidores , Tetrazoles/uso terapéutico , Biomarcadores/sangre , Compuestos de Bifenilo , Método Doble Ciego , Combinación de Medicamentos , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Estimación de Kaplan-Meier , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Factores de Riesgo , Volumen Sistólico/fisiología , Sobrevivientes , Resultado del Tratamiento , Troponina/sangre , ValsartánRESUMEN
Purpose: To evaluate myocardial T1 mapping and extracellular volume (ECV) parameters in different stages of Chagas cardiomyopathy and determine whether they are predictive of disease severity and prognosis. Materials and Methods: Prospectively enrolled participants (July 2013 to September 2016) underwent cine and late gadolinium enhancement (LGE) cardiac MRI and T1 mapping with a precontrast (native) or postcontrast modified Look-Locker sequence. The native T1 and ECV values were measured among subgroups that were based on disease severity (indeterminate, Chagas cardiomyopathy with preserved ejection fraction [CCpEF], Chagas cardiomyopathy with midrange ejection fraction [CCmrEF], and Chagas cardiomyopathy with reduced ejection fraction [CCrEF]). Cox proportional hazards regression and the Akaike information criterion were used to determine predictors of major cardiovascular events (cardioverter defibrillator implant, heart transplant, or death). Results: In 107 participants (90 participants with Chagas disease [mean age ± SD, 55 years ± 11; 49 men] and 17 age- and sex-matched control participants), the left ventricular (LV) ejection fraction and the extent of focal and diffuse or interstitial fibrosis were correlated with disease severity. Participants with CCmrEF and participants with CCrEF showed significantly higher global native T1 and ECV values than participants in the indeterminate, CCpEF, and control groups (T1: 1072 msec ± 34 and 1073 msec ± 63 vs 1010 msec ± 41, 1005 msec ± 69, and 999 msec ± 46; ECV: 35.5% ± 3.6 and 35.0% ± 5.4 vs 25.3% ± 3.5, 28.2% ± 4.9, and 25.2% ± 2.2; both P < .001). Remote (LGE-negative areas) native T1 and ECV values were also higher (T1: 1056 msec ± 32 and 1071 msec ± 55 vs 1008 msec ± 41, 989 msec ± 96, and 999 msec ± 46; ECV: 30.2% ± 4.7 and 30.8% ± 7.4 vs 25.1% ± 3.5, 25.1% ± 3.7, and 25.0% ± 2.2; both P < .001). Abnormal remote ECV values (>30%) occurred in 12% of participants in the indeterminate group, which increased with disease severity. Nineteen combined outcomes were observed (median follow-up time: 43 months), and a remote native T1 value greater than 1100 msec was independently predictive of combined outcomes (hazard ratio, 12 [95% CI: 4.1, 34.2]; P < .001). Conclusion: Myocardial native T1 and ECV values were correlated with Chagas disease severity and may serve as markers of myocardial involvement in Chagas cardiomyopathy that precede LGE and LV dysfunction.Keywords: MRI, Cardiac, Heart, Imaging Sequences, Chagas Cardiomyopathy Supplemental material is available for this article. © RSNA, 2023.
RESUMEN
AIMS: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is being tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC-HF) trial. Here we describe the baseline characteristics of participants in GALACTIC-HF and how these compare with other contemporary trials. METHODS AND RESULTS: Adults with established HFrEF, New York Heart Association (NYHA) functional class ≥II, ejection fraction ≤35%, elevated natriuretic peptides and either current hospitalization for heart failure or history of hospitalization/emergency department visit for heart failure within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic-guided dosing: 25, 37.5, or 50 mg bid). A total of 8256 patients [male (79%), non-white (22%), mean age 65 years] were enrolled with a mean ejection fraction 27%, ischaemic aetiology in 54%, NYHA class II 53% and III/IV 47%, and median N-terminal pro-B-type natriuretic peptide 1971 pg/mL. Heart failure therapies at baseline were among the most effectively employed in contemporary heart failure trials. GALACTIC-HF randomized patients representative of recent heart failure registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure <100 mmHg (n = 1127), estimated glomerular filtration rate <30 mL/min/1.73 m2 (n = 528), and treated with sacubitril/valsartan at baseline (n = 1594). CONCLUSIONS: GALACTIC-HF enrolled a well-treated, high-risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation.
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Insuficiencia Cardíaca , Urea/análogos & derivados , Anciano , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Volumen Sistólico/efectos de los fármacos , Urea/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
INTRODUCTION: Chagas' disease is one of the most important causes of dilated cardiomyopathy in South and Central America. It is an inflammatory cardiomyopathy. We wanted to investigate whether it could have the same response to aldosterone antagonism as demonstrated before in other dilated cardiomyopathies. OBJECTIVE: To evaluate the role of spironolactone in myocardial remodelling in a Chagas cardiomyopathy model. MATERIAL AND METHODS: We studied 60 Sirius Hamsters divided into: control (C) infected (Inf) and Inf plus spironolactone (Infsp, 40 mg/kg/day) groups, for 11 months. Echocardiography with colour doppler was performed. Left ventricular end diastolic diameter (LVEDD), fractional shortening (FS) and corrected isovolumic relaxation time (IRT) were evaluated, as well as interstitial collagen volume fraction (ICVF) and myocardial inflammation. RESULT: The results demonstrated that survival was improved by use of spironolactone in the chronic phase (p<0.04). Body weight (BW) was C:190 g, Inf:167 g*, Infsp:198 g (*p<0.05, compared to C and Infsp), LVEDD/BW was C:0.31, Inf: 0.35*, Infsp: 0.29 (*p<0.05, compared to C and Infsp), FS was C:38, Inf: 35.5, Infsp: 38 (with no statistical difference) and IRT was C: 23 msec, Inf: 26 msec*, Infsp: 22 msec (p<0.05, compared to C and Infsp). ICVF (%) was attenuated at LV (C: 0.34+/-0.1, Inf: 1.75+/-0.7*, Infsp: 0.95+/-0.2*; *p<0.05, p<0.05). CONCLUSION: Spironolactone attenuated the myocardial remodelling in Chagas cardiomyopathy, reduced mortality during the chronic phase and reduced inflammatory infiltration.
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Cardiotónicos/farmacología , Cardiomiopatía Chagásica/patología , Antagonistas de Receptores de Mineralocorticoides/farmacología , Espironolactona/farmacología , Trypanosoma cruzi , Remodelación Ventricular/efectos de los fármacos , Aldosterona/metabolismo , Animales , Cardiomiopatía Chagásica/diagnóstico por imagen , Colágeno/análisis , Cricetinae , Modelos Animales de Enfermedad , Ecocardiografía Doppler en Color , Femenino , Mesocricetus , Miocardio/químicaRESUMEN
OBJECTIVE: To determine whether NT pro-BNP levels are high in patients reporting pericardial diseases, as well as to investigate how they relate to diastolic dysfunction echocardiographic measures. METHODS: Twenty-five patients were split into two groups: 1) pericardial effusion (PE): 15 patients; 2) constrictive pericarditis (CP): 10 patients. A control group was made up with 30 individuals reporting no heart disease. Pericardial effusion was evaluated by bidimensional echocardiogram, with restriction evaluated by pulsed Doppler of mitral flow. CP diagnosis was confirmed by MRI. NT pro-BNP levels were measured by immunoassay and detected by electrochemiluminescence. RESULTS: From the 15 PD patients, 14 reported relevant PD, and only 1, moderate PD. Log NT pro-BNP was shown to be higher in PD (p < 0.05), with log mean of 2.31 pg/ml and CP (p < 0.05), with log mean of 2.67 pg/ml, when compared to control group, log mean of 1.32 pg/ml. No difference was reported between PD and CP (p = 0.149). The NT pro-BNP log showed to be correlated to peak velocity of the E wave (r = 0.845; p = 0.001) and with E/A (r = 0.717; p = 0.003). CONCLUSION: NT pro-BNP is shown to have increased in pericardial diseases, and is associated to diastolic dysfunction. It may serve as an additional method in quantifying restriction.
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Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Derrame Pericárdico/diagnóstico , Pericarditis Constrictiva/diagnóstico , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Diástole/fisiología , Ecocardiografía Doppler en Color , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derrame Pericárdico/diagnóstico por imagen , Pericarditis Constrictiva/diagnóstico por imagenRESUMEN
OBJECTIVE: To analyze left ventricular (LV) regional wall motion in patients with endomyocardial fibrosis (EMF). METHODS: The study comprised 88 patients, 59 of the female sex, with a mean age of 39+/-13 years (range, 9 to 65) and with echocardiographic and angiographic evidence of left ventricular EMF. The intensity of fibrous tissue buildup on contrast cineventriculography was classified as mild, moderate, or severe. The overall left ventricular ejection fraction (LVEF) was determined by using the area-length method on ventriculography. The motion was measured in 100 equidistant chords perpendicular to the centerline drawn in the middle of the final diastolic and systolic contours and normalized to cardiac size. Five left ventricular segments were analyzed: A--apical; AL--anterolateral; AB--anterobasal; IA--inferoapical; IB--inferobasal. Abnormality was expressed in units of standard deviation of the mean motion in a normal population of reference, comprised of 103 patients with normal LV according to clinical and electrocardiographic data, and angiographic standards. RESULTS: Mean LVEF was 0.47+/-0.12. Fibrous tissue buildup in the left ventricle was mild in 12 patients, moderate in 40, and severe in 36. The regions with the poorest ventricular wall motion were A (-1.4+/-1.6 standard deviation/chords) and IA (-1.6+/-1.8 standard deviation/chords) compared with that in AB (-0.3+/-1.9 standard deviation/chords), AL (-0.5+/-1.8 standard deviation/chords) and IB (-0.9+/-1.3 standard deviation/chords). No relation was observed between the intensity of fibrous tissue buildup and regional ventricular wall motion. CONCLUSION: A change in LV regional wall motion exists in EMF, and it is independent of the intensity of fibrous tissue buildup qualitatively assessed. Nonuniform involvement of the LV should be considered when planning surgery for this disease.
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Fibrosis Endomiocárdica/fisiopatología , Función Ventricular Izquierda/fisiología , Adolescente , Adulto , Anciano , Niño , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana EdadAsunto(s)
Cardiología , Mejoramiento de la Calidad , Brasil , Hospitales Públicos , Proyectos de InvestigaciónRESUMEN
BACKGROUND: Chagas disease is a cause of dilated cardiomyopathy, and information about left atrial (LA) function in this disease still lacks. OBJECTIVE: To assess the different LA functions (reservoir, conduit and pump functions) and their correlation with the echocardiographic parameters of left ventricular (LV) systolic and diastolic functions. METHODS: 10 control subjects (CG), and patients with Chagas disease as follows: 26 with the indeterminate form (GI); 30 with ECG alterations (GII); and 19 with LV dysfunction (GIII). All patients underwent M-mode and two-dimensional echocardiography, pulsed-wave Doppler and tissue Doppler imaging. RESULTS: Reservoir function (Total Emptying Fraction: TEF): (p <0.0001), lower in GIII as compared to CG (p = 0.003), GI (p <0.001) and GII (p <0.001). Conduit function (Passive Emptying Fraction: PEF): (p = 0.004), lower in GIII (GIII and CG, p = 0.06; GI and GII, p = 0.06; and GII and GIII, p = 0.07). Pump function (Active Emptying Fraction: AEF): (p = 0.0001), lower in GIII as compared to CG (p = 0.05), GI (p<0.0001) and GII (p = 0.002). There was a negative correlation of E/e' (average) with the reservoir and pump functions (TEF and AEF), and a positive correlation of e' (average) with s' wave (both septal and lateral walls) and the reservoir, conduit and pump LA functions. CONCLUSION: An impairment of LA functions in Chagas cardiomyopathy was observed.
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Función del Atrio Izquierdo/fisiología , Cardiomiopatía Chagásica/fisiopatología , Disfunción Ventricular Izquierda/fisiopatología , Adulto , Cardiomiopatía Dilatada/fisiopatología , Estudios de Casos y Controles , Cardiomiopatía Chagásica/diagnóstico por imagen , Ecocardiografía Doppler , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica/fisiología , Valores de Referencia , Estadísticas no Paramétricas , Volumen Sistólico/fisiología , Disfunción Ventricular Izquierda/diagnóstico por imagenRESUMEN
Chronic Chagas' disease cardiomyopathy (CCC) is caused by the protozoan Trypanosoma cruzi, and it affects 30% of the 16-18 million people infected in Latin America. A good rodent model that develops a dilated cardiomyopathy closely resembling human CCC after T. cruzi infection is still needed. We compared the cardiomyopathy developed by T. cruzi-infected Syrian hamsters with human Chagas' disease cardiomyopathy using quantitative methods. Female hamsters were infected with 3.5 x 10(4) (G1, n = 10) or 10(5) (G2, n = 10) T. cruzi Y strain blood trypomastigotes. Control animals (C, n = 10) were injected with saline solution. Cardiac function was assessed by echocardiography at 4, 8 and 12 months post-infection. Heart sections were submitted to histopathological/morphometric analysis 12 months post-infection. At this time, ventricular dysfunction and diffuse or multi-focal myocarditis were observed in 91% and 100% of G1 and G2 infected groups, respectively. Median interstitial collagen volumes in groups C, G1 and G2 were 1.2%, 1.9% and 3.9%, respectively, and were significantly higher in group G2 than in group C. Among infected animals, myocarditis showed a positive correlation with interstitial fibrosis. Deaths in the chronic phase (8-12 months post-infection) were more frequent among G2 than G1, and were associated with macroscopic ventricular dilation, severe myocarditis and increased fibrosis values, along with an earlier onset of ventricular dysfunction. The T. cruzi chronically infected Syrian hamster develops a cardiomyopathy which resembles human Chagas' disease cardiomyopathy, and might be an adequate tool to investigate pathogenic mechanisms of this disease and to search for novel therapeutic strategies.
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Cardiomiopatía Chagásica/patología , Modelos Animales de Enfermedad , Miocardio/patología , Animales , Cardiomiopatía Chagásica/fisiopatología , Tejido Conectivo/patología , Cricetinae , Femenino , Corazón/parasitologíaRESUMEN
The association of anomalous right coronary artery originating from the pulmonary artery and constrictive pericarditis has never been showed in the literature. We present the first case of this unusual association in a patient with right heart failure. After diagnosis, the patient was referred to surgery and underwent phrenic-to-phrenic pericardiectomy; graft implant of right internal thoracic artery to right coronary artery; and ligation of the anomalous origin of the right coronary artery from the pulmonary artery. Such procedures solved the potential risk of sudden death related to anomalous right coronary artery originating from the pulmonary artery and alleviated the symptoms of heart failure caused by constrictive pericarditis.
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Anomalías de los Vasos Coronarios/diagnóstico , Pericarditis Constrictiva/diagnóstico , Arteria Pulmonar/anomalías , Anomalías de los Vasos Coronarios/complicaciones , Humanos , Masculino , Pericarditis Constrictiva/complicaciones , Adulto JovenAsunto(s)
Cardiomiopatía Chagásica , Ivabradina , Enfermedad de Chagas , Corazón , Insuficiencia Cardíaca , HumanosAsunto(s)
Cardiología , Mejoramiento de la Calidad , Proyectos de Investigación , Brasil , Hospitales PúblicosRESUMEN
Chagas disease is a cause of dilated cardiomyopathy, and information about left atrial (LA) function in this disease still lacks. To assess the different LA functions (reservoir, conduit and pump functions) and their correlation with the echocardiographic parameters of left ventricular (LV) systolic and diastolic functions. 10 control subjects (CG), and patients with Chagas disease as follows: 26 with the indeterminate form (GI); 30 with ECG alterations (GII); and 19 with LV dysfunction (GIII). All patients underwent M-mode and two-dimensional echocardiography, pulsed-wave Doppler and tissue Doppler imaging. Reservoir function (Total Emptying Fraction: TEF): (p <0.0001), lower in GIII as compared to CG (p = 0.003), GI (p <0.001) and GII (p <0.001). Conduit function (Passive Emptying Fraction: PEF): (p = 0.004), lower in GIII (GIII and CG, p = 0.06; GI and GII, p = 0.06; and GII and GIII, p = 0.07). Pump function (Active Emptying Fraction: AEF): (p = 0.0001), lower in GIII as compared to CG (p = 0.05), GI (p<0.0001) and GII (p = 0.002). There was a negative correlation of E/e’ An impairment of LA functions in Chagas cardiomyopathy was observed.
A doença de Chagas é uma causa de miocardiopatia dilatada, sendo ainda pouco conhecida a função do átrio esquerdo (AE) nessa doença. Avaliar as diferenças nas funções do AE (reservatório, conduto e bomba) e sua correlação com os parâmetros ecocardiográficos das funções sistólica e diastólica do ventrículo esquerdo (VE). 10 controles (GC) e os seguintes pacientes com doença de Chagas: 26 com a forma indeterminada (GI); 30 com alterações eletrocardiográficas (GII); e 19 com disfunção de VE (GIII). Todos os pacientes foram submetidos a ecocardiografia bidimensional e em modo M, Doppler pulsado e Doppler tecidual. Função de reservatório (fração de esvaziamento total: FET) (p < 0,0001), mais baixa no GIII do que no GC (p = 0,003), GI (p < 0,001) e GII (p < 0,001). Função de conduto (fração de esvaziamento passivo: FEP) (p = 0,004), mais baixa no GIII (GIII e GC, p = 0.06; GI e GII, p = 0.06; e GII e GIII, p = 0,07). Função de bomba (fração de esvaziamento ativo: FEA) (p = 0,0001), mais baixa no GIII do que no CG (p = 0,05), GI (p<0,0001) e GII (p = 0,002). Observou-se uma correlação negativa entre E/e’média e as funções de reservatório e de bomba (FET e FEA), e uma correlação positiva entre as ondas e’média e s’ (paredes septal e lateral) e as funções de reservatório, conduto e bomba. Observou-se comprometimento das funções do AE na miocardiopatia chagásica.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Función del Atrio Izquierdo/fisiología , Cardiomiopatía Chagásica/fisiopatología , Disfunción Ventricular Izquierda/fisiopatología , Cardiomiopatía Dilatada/fisiopatología , Estudios de Casos y Controles , Cardiomiopatía Chagásica , Ecocardiografía Doppler , Contracción Miocárdica/fisiología , Valores de Referencia , Estadísticas no Paramétricas , Volumen Sistólico/fisiología , Disfunción Ventricular IzquierdaRESUMEN
BACKGROUND: In hypertrophic cardiomyopathy (HCM), interstitial myocardial fibrosis is an important histological modification that has been associated with sudden death and evolution toward myocardial dilation. OBJECTIVE: To prospectively evaluate the prognostic value of the collagen volume fraction in HCM. METHODS: An endomyocardial biopsy of the right ventricle was successfully performed in 21 symptomatic patients with HCM. The myocardial collagen volume fraction (CVF) was determined by histology. The CVF was also determined in fragments of nine normal hearts from subjects deceased from non-cardiac causes. The patients were divided into above-median CVF and below-median CVF groups, and their clinical and echocardiographic characteristics and survival curves were compared. RESULTS: Among the patients, the CVF ranged from 1.86% to 29.9%, median 6.19%; in normal hearts, from 0.13% to 1.46%, median 0.61% (p <0.0001 between HCM and control). There were no significant correlations between CVF and baseline echocardiographic measures. Patients with CVF < or =6.19% and CVF> 6.19% were compared and no baseline differences were observed. However, after an average follow-up period of 110 months, four deaths occurred (two sudden, two due to heart failure) in the group with increased CVF, whereas the patients of the group with lower CVF were all alive at the end of the period (p = 0.02). CONCLUSION: For the first time, myocardial fibrosis was prospectively associated with a worse prognosis in patients with HCM. Efforts should be directed to the quantification of myocardial fibrosis in HCM, on the premise that its association with the prognosis can aid in the stratification of risk for defibrillator implantation, and in the prescription of drugs that potentially promote myocardial repair.
Asunto(s)
Cardiomiopatía Hipertrófica/diagnóstico , Colágeno , Miocardio/patología , Adolescente , Adulto , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/mortalidad , Colágeno/análisis , Muerte Súbita Cardíaca/etiología , Métodos Epidemiológicos , Femenino , Fibrosis , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Adulto JovenRESUMEN
A associação da artéria coronária direita anômala com origem na artéria pulmonar e pericardite constritiva ainda não foi descrita na literatura. Apresentamos aqui o primeiro caso dessa associação inusitada em um paciente com quadro de insuficiência cardíaca direita. Após o diagnóstico, o paciente foi encaminhado para tratamento cirúrgico, sendo submetido a pericardiectomia frênico a frênico, implante de enxerto da artéria mamária interna direita para a coronária direita e ligadura da origem anômala da coronária direita da artéria pulmonar. Tais procedimentos resolveram o potencial risco de morte súbita pela anomalia coronária e aliviaram os sintomas de insuficiência cardíaca causados pela pericardite constritiva.
The association of anomalous right coronary artery originating from the pulmonary artery and constrictive pericarditis has never been showed in the literature. We present the first case of this unusual association in a patient with right heart failure. After diagnosis, the patient was referred to surgery and underwent phrenic-to-phrenic pericardiectomy; graft implant of right internal thoracic artery to right coronary artery; and ligation of the anomalous origin of the right coronary artery from the pulmonary artery. Such procedures solved the potential risk of sudden death related to anomalous right coronary artery originating from the pulmonary artery and alleviated the symptoms of heart failure caused by constrictive pericarditis.