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1.
BJOG ; 128(9): 1534-1545, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33969614

RESUMEN

OBJECTIVE: To assess the cost-effectiveness of mifepristone and misoprostol (MifeMiso) compared with misoprostol only for the medical management of a missed miscarriage. DESIGN: Within-trial economic evaluation and model-based analysis to set the findings in the context of the wider economic evidence for a range of comparators. Incremental costs and outcomes were calculated using nonparametric bootstrapping and reported using cost-effectiveness acceptability curves. Analyses were performed from the perspective of the UK's National Health Service (NHS). SETTING: Twenty-eight UK NHS early pregnancy units. SAMPLE: A cohort of 711 women aged 16-39 years with ultrasound evidence of a missed miscarriage. METHODS: Treatment with mifepristone and misoprostol or with matched placebo and misoprostol tablets. MAIN OUTCOME MEASURES: Cost per additional successfully managed miscarriage and quality-adjusted life years (QALYs). RESULTS: For the within-trial analysis, MifeMiso intervention resulted in an absolute effect difference of 6.6% (95% CI 0.7-12.5%) per successfully managed miscarriage and a QALYs difference of 0.04% (95% CI -0.01 to 0.1%). The average cost per successfully managed miscarriage was lower in the MifeMiso arm than in the placebo and misoprostol arm, with a cost saving of £182 (95% CI £26-£338). Hence, the MifeMiso intervention dominated the use of misoprostol alone. The model-based analysis showed that the MifeMiso intervention is preferable, compared with expectant management, and this is the current medical management strategy. However, the model-based evidence suggests that the intervention is a less effective but less costly strategy than surgical management. CONCLUSIONS: The within-trial analysis found that based on cost-effectiveness grounds, the MifeMiso intervention is likely to be recommended by decision makers for the medical management of women presenting with a missed miscarriage. TWEETABLE ABSTRACT: The combination of mifepristone and misoprostol is more effective and less costly than misoprostol alone for the management of missed miscarriages.


Asunto(s)
Abortivos/administración & dosificación , Aborto Retenido/tratamiento farmacológico , Mifepristona/administración & dosificación , Misoprostol/administración & dosificación , Abortivos/economía , Aborto Retenido/economía , Adolescente , Adulto , Análisis Costo-Beneficio , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Mifepristona/economía , Misoprostol/economía , Embarazo , Adulto Joven
2.
Radiother Oncol ; 190: 109984, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37926332

RESUMEN

BACKGROUND & AIM: Irradiation of the salivary glands during head and neck cancer treatment induces cellular senescence in response to DNA damage and contributes to radiation-induced hyposalivation by affecting the salivary gland stem/progenitor cell (SGSC) niche. Cellular senescence, such as that induced by radiation, is a state of cell-cycle arrest, accompanied by an altered pro-inflammatory secretome known as the senescence-associated secretory phenotype (SASP) with potential detrimental effects on the surrounding microenvironment. We hypothesized that the pro-regenerative properties of mesenchymal stem cells (MSCs) may attenuate cellular senescence post-irradiation. Therefore, here we evaluated the effects of adipose-derived MSCs (ADSCs) on the radiation-induced response of salivary gland organoids (SGOs). METHODS: Proteomic analyses to identify soluble mediators released by ADSCs co-cultured with SGOS revealed secretion of hepatocyte growth factor (HGF) in ADSCs, suggesting a possible role in the stem cell crosstalk. Next, the effect of recombinant HGF in the culture media of ex vivo grown salivary gland cells was tested in 2D monolayers and 3D organoid models. RESULTS: Treatment with HGF robustly increased salivary gland cell proliferation. Importantly, HGF supplementation post-irradiation enhanced proliferation at lower doses of radiation (0, 3, 7 Gy), but not at higher doses (10, 14 Gy) where most cells stained positive for senescence-associated beta-galactosidase. Furthermore, HGF had no effect on the senescence-associated secretory phenotype (SASP) of irradiated SGOs, suggesting there may be compensatory proliferation by cell-division competent cells instead of a reversal of cellular senescence after irradiation. CONCLUSION: ADSCs may positively influence radiation recovery through HGF secretion and can promote the ex vivo expansion of salivary gland stem/progenitor cells to enhance the effects of co-transplanted SGSC.


Asunto(s)
Factor de Crecimiento de Hepatocito , Células Madre Mesenquimatosas , Humanos , Factor de Crecimiento de Hepatocito/farmacología , Proteómica , Glándulas Salivales , Senescencia Celular/efectos de la radiación , Proliferación Celular
3.
Med Teach ; 33(4): 286-90, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21456985

RESUMEN

The use of learning objects (LOs), small chunks of learning stored digitally and reused or referenced to support learning, was described as a promising approach to the creation of e-learning modules or programmes. In practice, however, the early enthusiasm has waned and the approach has not been widely adopted. It is argued that this was due, at least in part, to a neglect of the pedagogy and an emphasis on the technical aspects of interoperability and reusability. This article describes a practical approach to constructing a learning module using LOs where a commentary links LOs selected for inclusion in the programme. The commentary tells the story of the e-learning module and provides the learner with a context for an LO. It can be viewed as a 'personal learning assistant' that advises students about the management of their learning and relates the e-learning module to the overall learning outcomes for the curriculum. The commentary also allows the lecturer to comment on LOs selected for inclusion in the programme which otherwise might have to be adapted or excluded when the programme was constructed. The use of a commentary to link and introduce LOs has been successfully adopted in the development of e-learning programmes. Teachers are encouraged to consider the approach and to look again at the use of LOs to create e-learning resources.


Asunto(s)
Instrucción por Computador , Objetivos , Aprendizaje , Educación Médica/métodos , Humanos , Internet , Programas Informáticos , Estados Unidos
4.
Med Teach ; 33(4): 311-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21456989

RESUMEN

BACKGROUND: E-learning has the potential to make important contributions to medical education, but there has been limited study of a blended approach in which the digital resources are introduced alongside traditional teaching methods such as lectures. METHODS: We describe the successful embedding of an e-learning resource into 3 of the 5 weeks of cardiovascular system teaching for 164 first-year medical students by providing scheduled slots in the timetables. A questionnaire completed by the students at the end of the 5 weeks had a response rate of 66%. Students varied in how they made use of the resource, some systematically working through it and others browsing and studying sections felt to be personally most relevant. RESULTS: Almost all (96%) rated the e-learning resources as probably or definitely of value: they particularly valued interactive activities, animations, video demonstrations, video clips of experts and self-assessment exercises. Graduate students had a significantly more favourable assessment of the e-learning resources than their undergraduate colleagues, while female students felt the value in supporting existing learning opportunities more strongly than male students. CONCLUSIONS: It should not be assumed that all students will choose to use an e-learning resource in the same way and instructional design should enable alternative approaches. The sequence in which the e-learning resource is used in relation to the other learning opportunities, such as lectures and PBL group discussions, may be important and merits further consideration. The experiences reported in this study provide encouragement and pointers for others engaged in the integration of e-learning in their curriculum.


Asunto(s)
Curriculum , Facultades de Medicina , Integración de Sistemas , Interfaz Usuario-Computador , Comportamiento del Consumidor , Femenino , Humanos , Masculino , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios
5.
Stem Cell Reports ; 16(11): 2813-2824, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34678204

RESUMEN

ß-Adrenergic signaling blockade is a mainstay of hypertension management. One percent of patients taking ß-blockers develop reduced salivary gland (SG) function. Here we investigate the role of SG progenitor cells in ß-blocker-induced hyposalivation, using human SG organoid cultures (SGOs). Compared with control SGs, initial low SG progenitor cell yield from patients taking ß-blockers was observed. When passaged, these SGOs recovered self-renewal and upregulated Notch pathway expression. Notch signaling was downregulated in situ in ß-adrenergic receptor-expressing luminal intercalated duct (ID) cells of patients taking ß-blockers. Control SGOs treated with ß-adrenergic agonist isoproterenol demonstrated increased proportion of luminal ID SGO cells with active Notch signaling. Control SGOs exposed to isoproterenol differentiated into more mature SGOs (mSGOs) expressing markers of acinar cells. We propose that ß-blocker-induced Notch signaling reduction in luminal ID cells hampers their ability to proliferate and differentiate into acinar cells, inducing a persistent hyposalivation in some patients taking ß-blocking medication.


Asunto(s)
Receptores Adrenérgicos/metabolismo , Receptores Notch/metabolismo , Glándulas Salivales/metabolismo , Transducción de Señal/fisiología , Células Madre/metabolismo , Agonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/farmacología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Humanos , Isoproterenol/farmacología , Organoides/citología , Organoides/metabolismo , Glándulas Salivales/citología , Salivación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Células Madre/citología
6.
BJOG ; 117(7): 870-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20394610

RESUMEN

OBJECTIVE: To compare the 'inside-out' versus 'outside-in' routes for transobturator tape insertion for urodynamic stress incontinence, and to identify independent risk factors for failure at 1 year. DESIGN: Prospective single-blinded randomised trial. SETTING: Tertiary urogynaecology centre. POPULATION: A cohort of 341 women undergoing transobturator tape procedures between April 2005 and April 2007. METHODS: Women were randomised to tension-free vaginal tape-obturator (TVT)-O for the 'inside-out' route (n = 170) and transobturator tape (TOT)-ARIS for the 'outside-in' route (n = 171). Participants completed validated symptom-severity, quality-of-life and sexual-function questionnaires before and after surgery. In addition, they completed the patient global impression of improvement questionnaire (PGI-I) and standard 1-hour pad test postoperatively. MAIN OUTCOME MEASURES: The primary outcome was the patient-reported success rate reported on the PGI-I scale. Secondary outcomes included objective cure rate and improvement in King's Health Questionnaire scores. RESULTS: A total of 341 women were recruited: 171 women to the 'outside-in' (TOT-ARIS) group and 170 to the 'inside-out' (TVT-O) group; 299 completed the 1-year follow up. The patient-reported success rate was 80% with no statistically significant differences between the groups ('outside-in' 77.6% versus 'inside-out' 81.2%; OR 1.25; 95% CI 0.71, 2.20; P = 0.54). The objective cure rate was 91% with no statistically significant difference between the groups ('outside-in' 88% versus 'inside-out' 94%; OR 2.21; 95% CI 0.85, 5.75; P = 0.157). Previous incontinence surgery (OR 1.41; 95% CI 1.18, 1.91; P = 0.029) and preoperative urgency incontinence (OR 1.78; 95% CI 1.21, 3.91, P = 0.048) were significant risk factors for failure of transobturator tape at the 1-year follow up. CONCLUSIONS: There are no significant differences in patient reported and objective cure rates between 'inside-out' and 'outside-in' transobturator tapes. Quality of life and sexual function significantly improved following surgery. Both previous incontinence surgery and preoperative urgency incontinence are associated with significantly lower patient-reported cure rates.


Asunto(s)
Cabestrillo Suburetral , Incontinencia Urinaria de Esfuerzo/cirugía , Femenino , Humanos , Complicaciones Intraoperatorias/etiología , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Factores de Riesgo , Disfunciones Sexuales Fisiológicas/etiología , Método Simple Ciego , Resultado del Tratamiento
7.
J Am Coll Cardiol ; 37(7): 1800-7, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11401114

RESUMEN

OBJECTIVES: The study was designed to comprehensively evaluate the circadian effects of aldosterone blockade on autonomic tone and QT dispersion in chronic heart failure (CHF). BACKGROUND: Spironolactone therapy given in addition to angiotensin-converting enzyme inhibitors improved survival in CHF, but the mechanism of its benefit is uncertain. Experimental evidence suggests that aldosterone may have detrimental effects on the autonomic nervous system, especially during the morning hours. METHODS: Twenty-eight patients with New York Heart Association class II to IV CHF received spironolactone 50 mg daily and placebo for four weeks each in a double-blind crossover fashion. After each treatment phase, a full circadian assessment was undertaken of spironolactone's autonomic effects. The assessment included monitoring heart rate, QT dispersion, continuous Holter recordings, heart rate variability (HRV) and norepinephrine kinetics. RESULTS: Spironolactone significantly reduced all indices of QT dispersion. The reductions in QTcmax, QTd and QTcd were greatest at 6 AM. In addition, spironolactone had favorable autonomic effects, which were limited to the morning (6-10 AM), including heart rate reduction and an improvement in HRV. CONCLUSIONS: Spironolactone reduced heart rate and improved HRV and QT dispersion in CHF. Its effects were particularly prominent during the morning hours.


Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Electrocardiografía/efectos de los fármacos , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca/efectos de los fármacos , Antagonistas de Receptores de Mineralocorticoides/farmacología , Espironolactona/farmacología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Norepinefrina/farmacocinética
8.
J Am Coll Cardiol ; 13(6): 1377-81, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2522959

RESUMEN

To investigate the significance of the electrocardiographic (ECG) pattern of left ventricular hypertrophy and strain, two groups of asymptomatic patients with essential hypertension were compared. The patients were similar in terms of age, smoking habit, serum cholesterol and blood pressure levels, but differed in the presence (Group I, n = 23) or absence (Group II, n = 23) of the ECG pattern of left ventricular hypertrophy and strain. Group I patients had significantly more episodes of exercise-induced ST segment depression (14 versus 4, p less than 0.05) and reversible thallium perfusion abnormalities (11 of 23 versus 3 of 23, p less than 0.05) despite similar exercise capacity and absence of chest pain. Nonsustained ventricular tachycardia was detected on 24 h ambulatory ECG monitoring in two patients in Group I, but no patient in Group II. Coronary arteriography performed in 20 Group I patients demonstrated significant coronary artery disease in 8 patients. This study has shown that there is a subgroup of hypertensive patients with ECG left ventricular hypertrophy and strain who have covert coronary artery disease. This can be detected by thallium perfusion scintigraphy, and may contribute to the increased risk known to be associated with this ECG abnormality.


Asunto(s)
Cardiomegalia/fisiopatología , Enfermedad Coronaria/diagnóstico , Electrocardiografía , Hipertensión/fisiopatología , Angiografía , Angiografía Coronaria , Enfermedad Coronaria/fisiopatología , Prueba de Esfuerzo , Femenino , Corazón/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Cintigrafía , Factores de Riesgo , Radioisótopos de Talio
9.
Postgrad Med J ; 81(962): 777-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16344302

RESUMEN

BACKGROUND: Smaller echocardiography machines, when used in hospitals, are accurate for detecting left ventricular dysfunction and valvular disease. This paper assessed the detection of left ventricular dysfunction and of valvular disease in the community setting by a smaller machine. AIMS: To measure the agreement in patients with suspected heart failure between community echocardiography and traditional echocardiography in the hospital in detecting left ventricular dysfunction and significant valve disease. METHODS: Suspected heart failure patients were referred to one of the authors (SJ) for community echocardiography using a Siemens Cypress machine. The patients had a second echocardiogram in the hospital by another sonographer who was blinded to the results of the first echocardiogram. The reports of the two sonographers were assessed for agreement using kappa statistics. RESULTS: 458 patients had a community echocardiogram and 136 agreed to a second echocardiogram in the hospital. There was excellent agreement, kappa = 0.87 (0.06 SE), for the detection of left ventricular dysfunction between community echocardiography and the hospital machine. The detection of significant valvular disease was good, kappa = 0.75 (0.06) between the community echocardiogram and hospital machines. CONCLUSIONS: In suspected heart failure patients, community echocardiography gives comparable results to traditional hospital echocardiography for left ventricular dysfunction detection and for significant valvular disease detection.


Asunto(s)
Servicios de Salud Comunitaria/normas , Hospitalización , Disfunción Ventricular Izquierda/diagnóstico por imagen , Anciano , Atención Ambulatoria/normas , Ecocardiografía Doppler en Color/instrumentación , Ecocardiografía Doppler en Color/normas , Femenino , Insuficiencia Cardíaca , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Humanos , Masculino , Variaciones Dependientes del Observador , Escocia , Sensibilidad y Especificidad
10.
Cardiovasc Res ; 27(12): 2200-4, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8313429

RESUMEN

OBJECTIVE: Potent therapy that could be locally delivered to inhibit blood factor-vessel wall interaction and which would remain localised to the site of damage may avoid the side effects of systemic drugs in the treatment of disorders such as subacute thrombosis of saphenous vein grafts and intravascular stents. We therefore assessed the feasibility of developing a targeted antithrombotic conjugate by covalently cross-linking urokinase to a monoclonal antibody to platelet glycoprotein IIb/IIIa (M735) and a monoclonal antibody against damaged endothelium (P14G11). METHODS: Conjugation was carried out using N-succinimidyl-3-(2-pyridyldithio) propionate as the cross-linking reagent. The conjugate was assessed in vitro and in an in vivo model of thrombosis and local delivery. RESULTS: The conjugate formed, ATC(3), retained specificity for damaged endothelial cells and platelets and had urokinase activity of approximately 10,000 IU.mg-1 protein. Persistence of urokinase activity on binding to intact platelets and scratch damaged endothelial monolayer preparations was confirmed. Platelet aggregation studies (using ADP and collagen) revealed complete inhibition by ATC(3) at a dose of 5 micrograms.ml-1 while an unconjugated mixture of M735 (20 micrograms.ml-1), P14G11 (20 micrograms.ml-1), and urokinase (200 IU.ml-1) failed to inhibit completely platelet aggregation induced by ADP. In an in vivo model of thrombosis and vascular injury, local delivery of ATC(3) significantly reduced the weight of thrombus formed [median 13 mg (interquartile range 9-20)] compared to an unconjugated mixture of M735, P14G11 and urokinase [35 mg (28-45)] and urokinase alone [41 mg (33-55)]. CONCLUSIONS: It is possible to produce a targeted antithrombotic conjugate which retains activity of all its individual components.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Fibrinolíticos/síntesis química , Inhibidores de Agregación Plaquetaria/síntesis química , Succinimidas/síntesis química , Activador de Plasminógeno de Tipo Uroquinasa/farmacología , Animales , Endotelio Vascular/inmunología , Endotelio Vascular/lesiones , Fibrinolíticos/farmacología , Ratones , Ratones Endogámicos BALB C , Inhibidores de Agregación Plaquetaria/farmacología , Glicoproteínas de Membrana Plaquetaria/inmunología , Ratas , Ratas Wistar , Succinimidas/farmacología
11.
Hypertension ; 18(3 Suppl): I126-32, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1832413

RESUMEN

Hypertension is an established risk factor for all the clinical sequelae of coronary artery disease. Despite this, individual therapeutic trials of antihypertensive therapy have not demonstrated the expected reduction in coronary morbidity and mortality. This apparent failure is perhaps not surprising when one considers the multifactorial nature of coronary artery disease and the different ways in which hypertension may affect the coronary circulation. Much debate has also centered on the antihypertensive therapy used in major trials in that it may in some way prevent the reduction in coronary mortality. However, thus far no clear evidence of a harmful effect has emerged. Reducing coronary mortality in hypertensive patients is a major challenge but one that can be effectively surmounted by approaching these different factors in a concerted manner. The ultimate goal must be to prevent the development of hypertension and left ventricular hypertrophy, but until such time as that can be achieved, the early detection of hypertension is mandatory. The optimal levels of systolic and diastolic blood pressures must be established. Studies on the more recent antihypertensive agents hold promise for a more specific effect on the atherosclerotic process as well as sustained control of arterial blood pressure. In this regard, it would seem essential to develop more precise ways of quantifying atherosclerosis and thus clarifying the nature of its relation to hypertension. Finally, management of hypertension must include precise assessment of the patient's overall cardiovascular risk status and appropriate and aggressive management of all risk factors for coronary artery disease.


Asunto(s)
Enfermedad Coronaria/etiología , Hipertensión/complicaciones , Animales , Antihipertensivos/farmacología , Cardiomegalia/etiología , Cardiomegalia/prevención & control , Hemodinámica , Humanos , Hipertensión/prevención & control , Hipertensión/terapia , Factores de Riesgo , Función Ventricular Izquierda
12.
Atherosclerosis ; 85(2-3): 193-202, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2102083

RESUMEN

This report describes the response of patients with severe coronary artery disease to a dynamic fat load test and monitors the change induced by fenofibrate therapy. The presence of disease was associated with prolonged and exaggerated hypertriglyceridemia following the meal and with lower basal HDL cholesterol and HDL subfraction masses. A further indicator of risk was the persistence of increased amounts of retinyl palmitate in the plasma of severely affected individuals 24 h after its ingestion with the meal. These observations are consistent with the proposal that the clearance of chylomicrons and their remnants is impaired in coronary atherosclerosis. Fenofibrate reduced alimentary lipemia following the fat load in both normo- and hypercholesterolemic subjects. This was associated with a 10% rise in plasma HDL cholesterol levels. The improvement in chylomicron catabolism probably derived from a 37% increase (P less than 0.001) in lipoprotein lipase activity induced by fenofibrate. Hepatic lipase on the other had was only slightly affected by treatment.


Asunto(s)
Enfermedad Coronaria/sangre , Fenofibrato/uso terapéutico , Lípidos/sangre , Adulto , Colesterol/sangre , HDL-Colesterol/sangre , VLDL-Colesterol/sangre , Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/enzimología , Grasas de la Dieta/administración & dosificación , Diterpenos , Heparina/farmacología , Humanos , Lipasa/sangre , Lipoproteína Lipasa/sangre , Hígado/enzimología , Persona de Mediana Edad , Ésteres de Retinilo , Triglicéridos/sangre , Vitamina A/análogos & derivados , Vitamina A/sangre
13.
Am J Med ; 86(4): 421-6, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2539017

RESUMEN

PURPOSE: Short-term therapy with angiotensin converting enzyme (ACE) inhibitors for hypertension is effective and well tolerated, and compared with beta blockers, may cause fewer adverse reactions. Furthermore, enalapril has been observed to have a greater effect on systolic blood pressure than beta blockers. We therefore decided to compare the ACE inhibitor enalapril and the beta blocker atenolol as monotherapy in a double-blind study of patients with mild to moderate hypertension. PATIENTS AND METHODS: After a four-week placebo run-in period, 162 patients were allocated randomly to receive atenolol (50 to 100 mg daily) or enalapril (20 to 40 mg daily) for 12 weeks. To assess the influence of these drugs on quality of life, a series of psychologic tests was performed, and a subset of patients also underwent treadmill exercise and pulmonary function tests. RESULTS: In 147 patients who completed the study, enalapril reduced supine blood pressure by 19/12 mm Hg, compared with 9/7 mm Hg for atenolol (p less than 0.001/p less than 0.005). The modest blood pressure response to atenolol was not due to poor compliance. A target blood pressure of 140/90 mm Hg or less was achieved by 35 percent of enalapril-treated atenolol (p less than 0.01). The frequency and severity of adverse effects with the two drugs were similar, and few important differences emerged from the quality-of-life assessments. CONCLUSION: At the doses used, enalapril induced a greater short-term blood pressure response than atenolol; long-term studies of its safety and efficacy are required.


Asunto(s)
Atenolol/uso terapéutico , Enalapril/uso terapéutico , Hipertensión/tratamiento farmacológico , Adolescente , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Ensayos Clínicos como Asunto , Método Doble Ciego , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Memoria/efectos de los fármacos , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Respiración/efectos de los fármacos
14.
J Hypertens ; 11(10): 1003-10, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8258663

RESUMEN

OBJECTIVE: To evaluate the relationship between sudden cardiac death, ventricular arrhythmias and left ventricular hypertrophy in patients with hypertension. DATA IDENTIFICATION: Epidemiological studies assessing the importance of left ventricular hypertrophy as a risk factor for sudden cardiac death, studies assessing the prevalence of arrhythmias in left ventricular hypertrophy and studies assessing whether there is an electrophysiological substrate in the hypertrophied myocardium for ventricular dysrhythmias. RESULTS OF DATA ANALYSIS: Current evidence indicates that left ventricular hypertrophy is a risk factor for sudden cardiac death and that ventricular arrhythmias are more prevalent in hypertensive patients with than in those without left ventricular hypertrophy. However, there is a lack of evidence that these dysrhythmias are important as an underlying mechanism for sudden cardiac death, and there is no clear evidence that the hypertrophied myocardium is, itself, an arrhythmogenic substrate for malignant ventricular dysrhythmias. One possible mechanism for sudden cardiac death is myocardial ischaemia, either as a consequence of associated coronary disease or due to left ventricular hypertrophy, but this remains unproved. CONCLUSIONS: There is currently no evidence that the ventricular ectopic activity seen in patients with hypertensive left ventricular hypertrophy is a marker for sudden cardiac death. Clarification of the mechanisms involved in sudden cardiac death will help in selecting appropriate preventive and therapeutic strategies for these patients.


Asunto(s)
Arritmias Cardíacas/complicaciones , Muerte Súbita Cardíaca/etiología , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/complicaciones , Hipertrofia Ventricular Izquierda/etiología , Animales , Arritmias Cardíacas/etiología , Ventrículos Cardíacos , Humanos
15.
J Hypertens ; 8(8): 775-82, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2170517

RESUMEN

Three thousand seven hundred and eighty-three patients with non-malignant hypertension attending the Glasgow Blood Pressure Clinic between 1968 and 1983 were followed prospectively for an average of 6.5 years. Left ventricular hypertrophy (LVH) was present at the outset in 34.5% of the men, and 12.8% had ST-T changes. The corresponding figures for women were 21.5% and 8.8%. The prevalence of LVH increased with the severity of hypertension and was higher for a given blood pressure level in men than in women. All-cause age-adjusted mortality, expressed as deaths per 1000 patient-years, was 27.6 for men with normal electrocardiographs, 43.2 for men with LVH only (P less than 0.001) and 56.9 for men with LVH and ST-T changes (P less than 0.001). Similar trends were seen in women. The excess risk associated with LVH, with or without ST-T changes, could not be explained by age, increased blood pressure at referral to the clinic, or smoking habit, when these factors were considered either separately or in combination (regression analysis). Thus, our study demonstrates that LVH, with or without ST-T changes is an independent risk factor for mortality in hypertensive patients.


Asunto(s)
Cardiomegalia/mortalidad , Hipertensión/mortalidad , Factores de Edad , Cardiomegalia/etiología , Electrocardiografía , Femenino , Humanos , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , Factores de Riesgo , Escocia/epidemiología , Fumar/efectos adversos
16.
Am J Cardiol ; 60(17): 19I-22I, 1987 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-2961246

RESUMEN

Considerable attention has properly been focused in recent years on electrocardiographic abnormalities in patients with essential hypertension. It has been well established that both voltage evidence of left ventricular (LV) hypertrophy and LV hypertrophy and strain are ominous risk factors. A better understanding of the strain pattern in patients with LV hypertrophy has arisen from experimental animal studies showing how an increase in cardiac mass can lead to myocardial ischemia and from clinical studies showing that the patient with LV hypertrophy and strain is at risk from myocardial ischemia as a consequence of both associated coronary artery disease and increased LV mass. All the clinical syndromes associated with myocardial ischemia are increased in patients with LV hypertrophy and therefore earlier recognition of both cardiac involvement and myocardial ischemia is likely to improve survival in this particularly high-risk group of patients.


Asunto(s)
Cardiomegalia/etiología , Enfermedad Coronaria/etiología , Hipertensión/complicaciones , Animales , Presión Sanguínea , Cardiomegalia/fisiopatología , Circulación Coronaria , Enfermedad Coronaria/fisiopatología , Electrocardiografía , Humanos , Hipertensión/fisiopatología , Pronóstico , Ratas , Ratas Endogámicas SHR , Factores de Riesgo
17.
Am J Cardiol ; 67(4): 269-73, 1991 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-1990791

RESUMEN

The Doppler echocardiographic indexes of the tricuspid and mitral valves were assessed in 74 normal subjects (35 women and 39 men, mean age 45 years). A reproducibility study was also performed to examine the various sources of technical and biological variability. There were significantly higher peak early and late flow velocities across the mitral valve than across the tricuspid valve (0.67 +/- 0.13 and 0.47 +/- 0.12 vs 0.51 +/- 0.08 and 0.35 +/- 0.09 m.s-1, respectively; all p less than 0.0001). There was no significant difference between the early:late (E:A) velocity ratios of the 2 valves (1.65 +/- 0.73 vs 1.75 +/- 0.67, p less than 0.01). There was a steeper mitral early deceleration slope (-3.59 +/- 1.07 vs -2.95 +/- 0.91 m.s-2) but no significant difference in pressure half-times across the 2 valves (47 +/- 7 vs 51 +/- 12 ms, p less than 0.1). No influence of gender or body surface area could be demonstrated. There was a weak but significant relation between mitral peak early, peak atrial velocity and E:A ratio and age (r = -0.39, p less than 0.001, r = 0.23, p less than 0.01, and r = -0.245, p less than 0.01, respectively). There was no significant correlation between any of the tricuspid flow parameters and age. Respiration caused pronounced variability in the tricuspid Doppler indexes and all tricuspid flows were sampled and analyzed only during inspiration. The intra- and interobserver variabilities were small for all of the Doppler indexes measured, but the day-to-day variability was quite significant especially for the pressure half-time, deceleration and acceleration slope values.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Diástole/fisiología , Válvula Mitral/fisiología , Válvula Tricúspide/fisiología , Función Ventricular Derecha/fisiología , Adulto , Factores de Edad , Anciano , Ecocardiografía Doppler , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados
18.
Am J Cardiol ; 70(6): 681-8, 1992 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-1387288

RESUMEN

M-mode echocardiograms of 202 cardiac patients were studied with respect to the pattern of left ventricular (LV) geometry. Patients with normal LV mass and volume were separated from those who had LV hypertrophy or enlargement on the basis of LV mass and volume indexed to body surface area. The relative wall thickness that is currently used to classify LV hypertrophy/enlargement was found to be inadequate for differentiating between concentric and eccentric types of LV hypertrophy. A new M-mode echocardiographic classification is therefore proposed that accurately separates the different types of LV enlargement; it also allows identification of patients who have chronically dilated left ventricles at the expense of thin walls and thus have normal LV mass.


Asunto(s)
Cardiomegalia/diagnóstico por imagen , Ecocardiografía , Cardiopatías/diagnóstico por imagen , Cardiomegalia/clasificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Función Ventricular Izquierda/fisiología
19.
Am J Cardiol ; 69(9): 913-7, 1992 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-1532285

RESUMEN

Hypertensive patients with the electrocardiographic (ECG) pattern of left ventricular (LV) hypertrophy and strain are at increased risk of sudden death. It has been suggested that ventricular arrhythmias may be responsible. The prevalence and significance of ventricular arrhythmias was therefore studied in 90 hypertensive patients with LV hypertrophy and strain by undertaking 48-hour ambulatory ECG monitoring, ECG signal-averaging and programmed ventricular stimulation. Complex ventricular ectopic activity (Lown grade greater than or equal to 3) was detected in 59 patients (66%). Eleven patients (12%) had episodes of nonsustained ventricular tachycardia. There were no sustained arrhythmias either on ambulatory ECG monitoring or induced by programmed ventricular stimulation. Only 1 patient had ventricular late potentials recorded by the signal-averaged electrocardiogram. Therefore, there was little to suggest an underlying arrhythmogenic substrate in these patients. In conclusion, whereas ventricular arrhythmias occur often in patients with LV hypertrophy associated with systemic hypertension, their significance, if any, remains to be established.


Asunto(s)
Cardiomegalia/complicaciones , Hipertensión/complicaciones , Taquicardia/complicaciones , Adulto , Anciano , Cardiomegalia/fisiopatología , Electrocardiografía Ambulatoria , Electrofisiología , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Prevalencia , Procesamiento de Señales Asistido por Computador , Taquicardia/fisiopatología
20.
Aliment Pharmacol Ther ; 2(5): 451-9, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2979267

RESUMEN

Current interest in the pharmacological manipulation of portal pressure centres on the long-acting somatostatin analogue SMS 201-995. Nine haemodynamically stable cirrhotic patients who had previously bled from oesophageal varices had wedged and free hepatic venous pressures and cardiac index measured, using a Swan-Ganz catheter, before and at 60, 120 and 180 min after beginning a 60-min infusion of 25 microgram/h of SMS 201-995. Seven clinically similar patients had the same measurements performed without SMS 201-995. In all patients cardiac index was found to decrease and systemic vascular resistance increase at 60 min, although heart rates and arterial blood pressures were unchanged. The group given SMS 201-995 was significantly different from the control group in sustaining a fall in wedged hepatic venous pressure and trans-hepatic venous gradient at 60 min. SMS 201-995 causes a fall in portal pressure without a significant systemic haemodynamic effect.


Asunto(s)
Hemodinámica/efectos de los fármacos , Circulación Hepática/efectos de los fármacos , Cirrosis Hepática/fisiopatología , Octreótido/farmacología , Sistema Porta/fisiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema Porta/efectos de los fármacos
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