RESUMEN
Background. Very young adolescents receive little research and pragmatic attention regarding their sexual and reproductive health (SRH) needs. As a result, their experiences are often overlooked. Furthermore, when this age group is included in SRH education, the dominant public health lens tends to focus on health risks associated with sex, with less emphasis on a holistic approach that considers the socio-cultural and relational contexts in which adolescents' decision-making about sex and dating occurs. Objectives. To explore the beliefs, perceptions and decision-making pathways of adolescents about heterosexual sex, dating and relationships. Methods. The sample included 33 girls and 30 boys aged 10 - 14 years attending schools in rural Mpumalanga Province, South Africa. Data collection entailed participatory methodologies of group-based activities and individual interviews. Data were recorded and transcribed verbatim. Transcripts were coded and analysed using thematic analysis. Results. The findings focused on three themes: timing of dating, relationships and sex; gendered depictions of first sex; and agency in sexual decision-making. These themes shed light on the relational context in which adolescents' decision-making takes place and highlight the pervasive influence of wider gendered norms. Conclusion. Very young adolescents are not sexually naive and instead are faced with complex decisions regarding sex and dating. This age group is not, however, fully supported in developing a healthy, positive sexuality when emphasis is on the negative outcomes of sex. The paper concludes with recommendations for adolescent SRH programmes to provide a supportive environment for younger adolescents to make informed choices and develop positive, healthy sexualities
Asunto(s)
Adolescente , Preselección del Sexo , SudáfricaRESUMEN
Background. Early adolescence (ages 10 - 14) is a crucial stage of development. The importance of early intervention in improving adolescent sexual and reproductive health (SRH) is increasingly acknowledged. Yet, school-based sexuality education largely focuses on older adolescents, leaving very young adolescents to contend with conflicting information from different sources. This study responds to the need for contextually nuanced research with very young adolescents, which can inform policy and programmes aimed at improving their SRH outcomes. Objectives. To explore very young adolescents' sources of SRH knowledge and investigate the implications of both formal school-based sexuality education and informal sources of information for their SRH rights. Methods. This research was conducted with schoolgoing adolescents (aged 10 - 14) from the Gert Sibande district in rural Mpumalanga. Data were collected qualitatively using individual interviews and group-based participatory workshops, all conducted with the same participants. Transcribed data were analysed using thematic analysis. Results. Findings indicate that while formal transfer of SRH information takes place through school-based sexuality education, learners' sexual knowledge is also shaped by informal sources, including household observations and sexual play. We identify three themes that cut across sources of SRH knowledge and position young adolescents in contradictory ways: prohibitive messaging, the notion of childhood innocence and everyday sexual learning. Conclusion. Recommendations are made for comprehensive sexuality education that is responsive to this age group's needs, draws on their everyday lived experiences and optimises the opportunities offered by foregrounding agency, while remaining cognisant of structural constraints
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Adolescente , Conductas de Riesgo para la Salud , Educación Sexual , Sudáfrica , Adulto JovenRESUMEN
We report a case of iatrogenic hydropneumopericardium in a patient with diffuse scleroderma. The transthoracic echocardiogram revealed classical features of this condition. This case resolved spontaneously after five days using only 60% oxygen, which may have augmented resolution in this instance.
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Pericardiocentesis/efectos adversos , Neumopericardio/etiología , Ecocardiografía , Femenino , Humanos , Enfermedad Iatrogénica , Persona de Mediana Edad , Terapia por Inhalación de Oxígeno , Derrame Pericárdico/cirugía , Neumopericardio/diagnóstico por imagen , Neumopericardio/terapia , Esclerodermia Difusa/complicacionesRESUMEN
Isolated left ventricular non-compaction (LVNC) is a genetic disease that is being increasingly recognised in patients presenting with heart failure of unknown origin. In this case report, we describe a patient with classic LVNC without clinical heart failure and with normal left ventricular ejection fraction.
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No Compactación Aislada del Miocardio Ventricular/fisiopatología , Volumen Sistólico , Adulto , Angiografía Coronaria , Diástole/fisiología , Ecocardiografía Doppler , Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , No Compactación Aislada del Miocardio Ventricular/diagnóstico por imagen , Sístole/fisiologíaRESUMEN
Paraneoplastic syndromes are cancer-associated endocrinological, haematological, dermatological or neurological disorders, which are directly related neither to the physical effects of the tumour mass, nor to invasion by the primary tumour, nor to metastasis of the tumour; nor are they associated either with the side-effects of anticancer treatment or with any of the complications of cancer. These syndromes are brought about by the ectopic production of biological mediators by the malignant tumour cells, or by immunological responses to the malignancy. Certain cancers are typically associated with specific paraneoplastic disorders. Though uncommonly, oral carcinomata have reportedly been associated with paraneoplastic pemphigus, humoral hypercalcaemia of malignancy, syndrome of inappropriate antidiuretic hormone, and paraneoplastic leukocytosis syndrome.
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Neoplasias de la Boca/complicaciones , Síndromes Paraneoplásicos/etiología , Biomarcadores de Tumor/fisiología , Humanos , Hipercalcemia/etiología , Síndrome de Secreción Inadecuada de ADH/etiología , Leucocitosis/etiología , Síndromes Paraneoplásicos Endocrinos/etiología , Síndromes Paraneoplásicos del Sistema Nervioso/etiología , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Pénfigo/etiologíaRESUMEN
Oral mucositis is a debilitating complication of anticancer treatment, characterised by erythematous, atrophic, erosive or ulcerative lesions. Oral mucositis is almost always painful, affects eating, sleeping, and speech and affects the physiological and social well-being of the patient. The pathophysiology of the condition is not well understood. Guidelines to the treatment of oral mucositis are often contradictory so that there is no evidence based standard treatment protocol. Therefore the treatment is empiric. This paper offers a brief review of current knowledge of the pathophysiology and treatment of oral mucositis.
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Antineoplásicos/efectos adversos , Irradiación Craneana/efectos adversos , Mucositis/etiología , Estomatitis/etiología , Factores de Edad , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Mucosa Bucal/patología , Mucositis/patología , Mucositis/terapia , Neutropenia/etiología , Cuidados Paliativos , Factores de Riesgo , Factores Sexuales , Estomatitis/patología , Estomatitis/terapiaRESUMEN
BACKGROUND: Although the beta1-adrenoreceptor (AR) Gly389Arg and alpha2c-AR Del322-325 gene variants are associated with the response to beta-AR-blocker therapy, whether this effect is associated with the risk for heart failure, or the severity or progression of heart failure is uncertain. AIMS: To assess the relationship between Gly389Arg and Del322-325 variants and the presence, severity and progression of idiopathic dilated cardiomyopathy (IDC) in 403 black South African patients. METHODS: Genotypes were identified using a restriction fragment length polymorphism-based technique and automated sequencing. Left ventricular ejection fraction (LVEF) and dimensions were determined at baseline and in 132 patients after six months of standard medical therapy excluding beta-AR-blockers (not indicated as standard care at the time of completing this study). RESULTS: All patients and controls genotyped for the alpha2c-AR variant were homozygous for the Del322-325 (risk) allele. The Gly389Arg polymorphism was not associated with IDC (control n = 429) (Arg389 allele homozygosity: odds ratio = 1.03, confidence limits = 0.78-1.35), nor did it predict LVEF and cavity dimensions either before or after therapy. CONCLUSION: In patients homozygous for the risk allele of the alpha2c-AR variant, the beta1-AR variant neither increased the risk for IDC nor predicted its severity or progression in patients not receiving beta-AR-blockers.
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Población Negra/genética , Cardiomiopatía Dilatada/genética , Polimorfismo Genético , Receptores Adrenérgicos alfa 2/genética , Receptores Adrenérgicos beta 1/genética , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/etnología , Cardiomiopatía Dilatada/patología , Cardiomiopatía Dilatada/fisiopatología , Fármacos Cardiovasculares/uso terapéutico , Estudios de Casos y Controles , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Sudáfrica , Volumen Sistólico/efectos de los fármacos , Volumen Sistólico/genética , Resultado del Tratamiento , Función Ventricular Izquierda/efectos de los fármacos , Función Ventricular Izquierda/genéticaRESUMEN
The aim of this report is to provide guidance to assist in the international convergence of quality assurance, benchmarking and assessment systems to improve dental education. Proposals are developed for mutual recognition of qualifications, to aid international movement and exchange of staff and students including and supporting developing countries. Quality assurance is the responsibility of all staff involved in dental education and involves three levels: internal, institutional and external. Benchmarking information provides a subject framework. Benchmarks are useful for a variety of purposes including design and validation of programmes, examination and review; they can also strengthen the accreditation process undertaken by professional and statutory bodies. Benchmark information can be used by institutions as part of their programme approval process, to set degree standards. The standards should be developed by the dental academic community through formal groups of experts. Assessment outcomes of student learning are a measure of the quality of the learning programme. The goal of an effective assessment strategy should be that it provides the starting point for students to adopt a positive approach to effective and competent practice, reflective and lifelong learning. All assessment methods should be evidence based or based upon research. Mutual recognition of professional qualifications means that qualifications gained in one country (the home country) are recognized in another country (the host country). It empowers movement of skilled workers, which can help resolve skills shortages within participating countries. These proposals are not intended to be either exhaustive or prescriptive; they are purely for guidance and derived from the identification of what is perceived to be 'best practice'.
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Benchmarking , Educación en Odontología/normas , Gestión de la Calidad Total , Competencia Clínica , Educación Continua en Odontología/normas , Evaluación Educacional/normas , Medicina Basada en la Evidencia , Docentes de Odontología , Personal Profesional Extranjero/normas , Humanos , Cooperación Internacional , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Control de Calidad , Estudiantes de Odontología , Gestión de la Calidad Total/organización & administraciónRESUMEN
Background : Although the Beta1-adrenoreceptor (AR) Gly389Arg and ?2c-AR Del322-325 gene variants are associated with the response to Beta-AR-blocker therapy; whether this effect is associated with the risk for heart failure; or the severity or progression of heart failure is uncertain. Aims : To assess the relationship between Gly389Arg and Del322-325 variants and the presence; severity and progression of idiopathic dilated cardiomyopathy (IDC) in 403 black South African patients. Methods : Genotypes were identified using a restriction fragment length olymorphism-based technique and automated sequencing. Left ventricular ejection fraction (LVEF) and dimensions were determined at baseline and in 132 patients after six months of standard medical therapy excluding Beta- AR-blockers (not indicated as standard care at the time of completing this study). Results : All patients and controls genotyped for the ?2c-AR variant were homozygous for the Del322-325 (risk) allele. The Gly389Arg polymorphism was not associated with IDC (control n = 429) (Arg389 allele homozygosity : odds ratio = 1.03; confidence limits = 0.78-1.35); nor did it predict LVEF and cavity dimensions either before or after therapy. Conclusion : in patients homozygous for the risk allele of the ?2c-AR variant; the Beta1-AR variant neither increased the risk for IDC nor predicted its severity or progression in patients not receiving Beta-AR-blockers
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Cardiomiopatías , Estudio Comparativo , Genotipo , Signos y SíntomasRESUMEN
In heart failure, the Arg16Gly and Gln27Glu polymorphisms of the beta2-adrenoreceptor (beta2-AR) gene are associated with exercise-capacity, clinical outcomes and response to beta-AR blocker therapy. Whether beta2-AR gene variants mediate these effects in-part through an impact on cardiac structural remodeling and pump function independent of the effects of beta-blockers is uncertain. We evaluated whether the Arg16Gly and Gln27Glu variants of the beta2-AR gene predict left ventricular ejection fraction (LVEF) and LV end diastolic diameter (LVEDD) in patients with idiopathic dilated cardiomyopathy (IDC) before and 6 months after receiving standard medical therapy other than beta-AR blockers. In all, 394 patients with IDC and 393 age and gender-matched controls were genotyped for the beta2-AR gene variants using restriction-fragment length polymorphism-based techniques. LVEF and dimensions were determined in 132 patients (of whom 71 were newly diagnosed) both at baseline and after 6 months. Genotype of neither variant was associated with the presence of IDC. Moreover, beta2-AR genotype did not determine LVEF or LV dimensions prior to initiating therapy. After 6 months of therapy, LVEF increased by 7.1+/-1.0 absolute units (P<0.0001) and LVEDD decreased by 0.27+/-0.06 cm (P<0.02). Adjusting for baseline values as well as gender, age, and type of angiotensin-converting enzyme inhibitor therapy received, genotype was associated with neither final LVEF and LVEDD, nor change in LVEF and LVEDD. In conclusion, these data suggest that in heart failure, the functional Arg16Gly and Gln27Glu variants of the beta2-AR gene have no independent effect on adverse structural remodeling and pump function.
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Cardiomiopatía Dilatada/genética , Fármacos Cardiovasculares/uso terapéutico , Polimorfismo de Longitud del Fragmento de Restricción , Receptores Adrenérgicos beta 2/genética , Función Ventricular Izquierda/genética , Remodelación Ventricular/genética , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/patología , Cardiomiopatía Dilatada/fisiopatología , Cardiotónicos/uso terapéutico , Fármacos Cardiovasculares/farmacología , Estudios de Casos y Controles , Digoxina/uso terapéutico , Diuréticos/uso terapéutico , Quimioterapia Combinada , Femenino , Furosemida/uso terapéutico , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Haplotipos , Ventrículos Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Volumen Sistólico/efectos de los fármacos , Volumen Sistólico/genética , Sístole , Factores de Tiempo , Resultado del Tratamiento , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacosAsunto(s)
Infecciones por Bacteroides/rehabilitación , Prótesis Maxilofacial , Noma/rehabilitación , Adulto , Infecciones por Bacteroides/diagnóstico , Terapia Combinada , Femenino , Humanos , Implantación de Prótesis Maxilofacial/métodos , Noma/diagnóstico , Planificación de Atención al Paciente , Diseño de Prótesis/métodos , Elastómeros de SiliconaRESUMEN
One of the primary problems in the management and care of infants born with cleft palates is that of achieving an adequate seal of the cleft to allow proper swallowing to take place. This article describes an interesting case in which a 14-month-old baby, who had received no surgical or prosthodontic treatment for her cleft palate, had developed her own 'obturation' mechanism to enable her to swallow efficiently.
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Fisura del Paladar/fisiopatología , Ingestión de Alimentos/fisiología , Conducta en la Lactancia , Alimentación con Biberón/instrumentación , Trastornos de Deglución/fisiopatología , Femenino , Humanos , LactanteRESUMEN
Between September 1989 and December 1991, modified De Vega tricuspid annuloplasty was performed in 43 patients who survived surgery for mitral or mitral plus aortic valve replacement. The preoperative indications for tricuspid annuloplasty were moderate to severe tricuspid regurgitation (TR) in 33 patients and mild or no TR but with a dilated tricuspid annulus (> or =30 mm) as measured by 2-dimensional echocardiography at end-diastole in 10 patients. The mean age was 31 +/- 13 years. The mean duration of follow-up was 57 +/- 18 months. Overall long-term mortality was 12%. On Doppler color flow mapping, postoperative severe TR was present in 1 patient and moderate TR in 4 patients at latest follow-up. The tricuspid annulus diameter decreased from 37 +/- 5 mm preoperatively to 24 +/- 6 mm at latest follow-up. During the study period, an additional 77 patients underwent mitral valve replacement or double valve replacement, but without tricuspid annuloplasty. Within this group, 38 patients had a preoperative tricuspid annulus diameter of > or =30 mm, and 5 of these patients (13%) developed moderate or severe TR in the postoperative period, which may have been prevented had clinicians adhered to the preoperative indications for tricuspid annuloplasty. Thus, preoperative echocardiographically documented moderate or severe TR or a tricuspid annulus diameter of > or =30 mm are valid indications for performing tricuspid annuloplasty; modified De Vega tricuspid annuloplasty is a durable procedure in rheumatic patients; it appears that reducing the diastolic tricuspid annulus diameter to 24 mm is adequate to prevent residual TR in the long term.
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Válvula Aórtica/cirugía , Toma de Decisiones , Implantación de Prótesis de Válvulas Cardíacas , Válvula Mitral/cirugía , Cardiopatía Reumática/cirugía , Insuficiencia de la Válvula Tricúspide/cirugía , Válvula Tricúspide/cirugía , Adulto , Válvula Aórtica/diagnóstico por imagen , Velocidad del Flujo Sanguíneo , Ecocardiografía Doppler en Color , Femenino , Estudios de Seguimiento , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Válvula Mitral/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Presión Esfenoidal Pulmonar , Reproducibilidad de los Resultados , Estudios Retrospectivos , Cardiopatía Reumática/complicaciones , Cardiopatía Reumática/fisiopatología , Volumen Sistólico , Tasa de Supervivencia , Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/etiología , Insuficiencia de la Válvula Tricúspide/fisiopatologíaRESUMEN
There is mounting evidence that patients with systemic lupus erythematosus (SLE) are prone to disseminated neisserial infections. We describe the first proven case of gonococcal endocarditis affecting the pulmonary valve in a patient known to have SLE. The clinical clues and pitfalls in diagnosis are discussed, and the role of echocardiography is highlighted. Possible reasons for the association of gonococcal endocarditis with SLE include pre-existing Libman. Sacks endocarditis, complement deficiency and abnormalities of the reticuloendothelial system.
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Endocarditis Bacteriana/complicaciones , Gonorrea/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Neisseria gonorrhoeae/aislamiento & purificación , Adulto , Ecocardiografía , Endocarditis Bacteriana/patología , Femenino , Gonorrea/patología , Enfermedades de las Válvulas Cardíacas/complicaciones , Enfermedades de las Válvulas Cardíacas/patología , Humanos , Lupus Eritematoso Sistémico/patología , Válvula Pulmonar/microbiologíaRESUMEN
Our data indicate that MVR, with or without chordal preservation, for pure severe MR in symptomatic younger rheumatic patients with a good preoperative ejection fraction results in normalization of LV size and performance by 1 year. Normalization of LV performance was only achieved at 1 year after surgery, and it is therefore essential to extend the assessment of LV function to at least 1 year postoperatively.
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Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Mitral/cirugía , Cardiopatía Reumática/cirugía , Función Ventricular Izquierda/fisiología , Adolescente , Adulto , Factores de Edad , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Masculino , Válvula Mitral , Insuficiencia de la Válvula Mitral/etiología , Insuficiencia de la Válvula Mitral/fisiopatología , Sistema de Registros , Análisis de Regresión , Cardiopatía Reumática/fisiopatología , Volumen Sistólico/fisiología , Factores de Tiempo , Resultado del TratamientoRESUMEN
The ultimate role of percutaneous balloon mitral valvotomy will depend on its potential for sustained improvement. Long-term outcome data including survival, reoperation and thromboembolism are available for surgical commissurotomy. However, length of follow up for percutaneous balloon mitral valvotomy is inadequate to acquire similar end-point data. We therefore hypothesized that comparison of changes in mitral valve area following balloon or surgical commissurotomy would serve as a useful surrogate end-point by which the long-term benefit of percutaneous balloon mitral valvotomy could be determined. Mitral valve area was determined by Doppler echocardiography following percutaneous balloon mitral valvotomy (N = 230) and surgical commissurotomy (N = 241, 130 closed and 111 open mitral commissurotomy). Regression lines of mitral valve area versus interval from intervention were constructed for each of the two groups. Nine clinical and echocardiographic variables were also analyzed to determine their predictive value for low mitral valve areas. Both groups showed similar and significant negative correlations for mitral valve area versus time (r = -0.48, r = -0.6, balloon vs. surgical commissurotomy respectively, p = 0.001 for both groups). The slopes of the regression lines for both groups were also similar (y = -0.007 x +1.9, y = -0.005 x +1.8, y = -0.006 x +1.8, p = NS). There were no differences in the prevalence of mitral regurgitation. Independent predictors of mitral restenosis according to multivariate analysis were time interval from surgery (p < 0.03), composite mitral valve morphology score (p < 0.04) and subvalvular disease (p < 0.04). Thus, there is a progressive decrease in mitral valve area following percutaneous mitral balloon valvotomy that, at least for the available duration of follow up, appears to parallel changes in valve area following closed or open mitral commissurotomy. A less pliable valve and more subvalvular disease are independent predictors of smaller valve areas. These data suggest that the long term clinical outcome following percutaneous balloon mitral valvotomy may be expected to be similar to the available data for surgical commissurotomy.
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Cateterismo , Estenosis de la Válvula Mitral/terapia , Válvula Mitral/cirugía , Adulto , Procedimientos Quirúrgicos Cardíacos/métodos , Cateterismo/métodos , Estudios Transversales , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Masculino , Insuficiencia de la Válvula Mitral , Estenosis de la Válvula Mitral/diagnóstico por imagen , Estenosis de la Válvula Mitral/cirugía , Complicaciones Posoperatorias , Pronóstico , Estudios Prospectivos , Recurrencia , Factores de RiesgoAsunto(s)
Ecocardiografía Transesofágica , Endocarditis Bacteriana/diagnóstico por imagen , Endocarditis Bacteriana/etiología , Prótesis Valvulares Cardíacas/efectos adversos , Humanos , Valor Predictivo de las Pruebas , Infecciones Relacionadas con Prótesis/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/etiologíaRESUMEN
OBJECTIVES: This study examined the long-term (3-month) effects of nebivolol, a new beta-adrenergic blocking agent, on cardiac performance in patients with dilated cardiomyopathy. BACKGROUND: Several beta-blocking drugs have been reported to have a beneficial hemodynamic effect in patients with dilated cardiomyopathy, but few data obtained in a placebo-controlled randomized study have addressed the mechanisms of improvement. METHODS: Twenty-four patients with dilated idiopathic (n = 22) or ischemic (n = 2) cardiomyopathy (ejection fraction 0.15 to 0.40) in stable New York Heart Association functional class II or III were entered into a double-blind randomized trial of nebivolol, a new, potent, selective beta 1-antagonist. Exercise time, invasive hemodynamic data (12- and 24-h monitoring) and variables of left ventricular function were examined at baseline and after 3 months of orally administered nebivolol (1 to 5 mg/day, n = 11) or placebo (n = 13). RESULTS: Heart rate decreased (group mean 85 to 71 beats/min vs. 87 to 87 beats/min with placebo) and stroke volume increased significantly (group mean 43 to 55 ml vs. 42 to 43 ml) with nebivolol; decreases in systemic resistance, systemic arterial pressure, wedge pressure and pulmonary artery pressure were not significantly different from those with placebo. Similar hemodynamic results were obtained in the catheterization laboratory. Analysis of high fidelity measurements of left ventricular pressure showed a decrease in left ventricular end-diastolic pressure in the nebivolol group (group mean 21 to 15 vs. 24 to 20 mm Hg with placebo) but no change in the maximal rate of pressure development or in two variables of left ventricular relaxation (maximal negative rate of change of left ventricular pressure [dP/dtmax] and the time constant tau). Left ventricular mass decreased (p = 0.04). Despite a decrease in heart rate with nebivolol, there was a slight decrease in left ventricular end-diastolic volume (p = NS). End-systolic volume tended to decrease (p = 0.07) despite no reduction in end-systolic stress. The net result was a significant increase in ejection fraction (group mean 0.23 to 0.33 vs. 0.21 to 0.23 with placebo), presumably as a result of an increase in contractile performance. This effect was corroborated by an increase in a relatively load-independent variable of myocardial performance. CONCLUSIONS: Nebivolol improved stroke volume, ejection fraction and left ventricular end-diastolic pressure, not through a measurable reduction in afterload or a lusitropic effect, but by improving systolic contractile performance.
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Antagonistas Adrenérgicos beta/farmacología , Benzopiranos/farmacología , Cardiomiopatía Dilatada/tratamiento farmacológico , Etanolaminas/farmacología , Hemodinámica/efectos de los fármacos , Antagonistas Adrenérgicos beta/uso terapéutico , Adulto , Benzopiranos/uso terapéutico , Cardiomiopatía Dilatada/fisiopatología , Método Doble Ciego , Etanolaminas/uso terapéutico , Tolerancia al Ejercicio/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nebivolol , Factores de TiempoRESUMEN
Intravenous atenolol was given to 31 patients just before balloon mitral valvotomy to assess the hemodynamic efficacy and safety of beta-blockade in mitral stenosis complicated by pulmonary hypertension. Hemodynamic response in patients with pulmonary resistance > 600 dynes.sec.cm-5 (group 2, n = 17) was compared with those (group 1, n = 14) with a resistance below this value. In addition to a higher pulmonary arterial resistance (by design), patients in group 2 had a higher systemic resistance, lower cardiac index, and smaller mitral valve area compared with those in group 1. After atenolol infusion, transmitral gradient and left atrial pressure improved similarly. In spite of the decline in left atrial pressure, pulmonary vascular resistance increased in both groups, more in group 2 (847 +/- 398 dynes.sec.cm-5 to 135 +/- 648 dynes.sec.cm-5) than in group 1 (291 +/- 149 dynes.sec.cm-5 to 363 +/- 200; p < 0.001 for drug effect and p = 0.027 for group effect by two-way analysis of variance). Cardiac index declined similarly from 2.77 +/- 0.51 L/min/m2 to 2.37 +/- 0.37 L/min/m2 in group 1 and from 2.33 +/- 0.58 L/min/m2 to 1.92 +/- 0.54 L/min/m2 in group 2. Systemic pressure tended to decline only in group 2 (mean aortic pressure, 89 +/- 12 mm Hg to 89 +/- 12 mm Hg in group 1 and 90 +/- 9 mm Hg to 83 +/- 12 mm Hg in group 2; p = 0.06 for group effect).(ABSTRACT TRUNCATED AT 250 WORDS)