RESUMEN
The occurrence of an autonomic disturbance early in acute myocardial infarction (AMI) has been reported: signs of sympathetic activation were mainly observed in relation to an anterior localization, whereas signs of vagal overactivity were more frequent in inferior wall AMI. Information is limited in relation to the persistence of these alterations during the early hours of AMI. We studied 33 patients with an AMI within 188 +/- 16 minutes from the onset of symptoms and 1 week after hospital admission. From a 20-minute Holter recording, we computed with autoregressive methodology, time and frequency domain indexes of heart rate variability. At admission, patients with an anterior wall AMI exhibited a smaller RR variance (593 +/- 121 ms2) than did those with an inferior wall AMI (1,122 +/- 191 ms2). In both groups the spectral profile was characterized by a predominant (73 +/- 4 and 61 +/- 4 normalized units) low frequency and by a small (13 +/- 2 and 22 +/- 3 normalized units) high-frequency component, indicating the presence of a sympathetic excitation and of a diminished vagal modulation. Although signs of sympathetic activation were more evident in patients with anterior wall AMI, no evidence of a vagal hyperactivity was observed in patients with inferior wall AMI. In the latter group, we noticed 1 week after the acute event an increase in the low-frequency component, which reached the values observed in patients with anterior wall AMI. Thrombolysis did not affect heart rate variability parameters. Thus, this study suggests the presence of an autonomic disturbance characterized by signs of sympathetic excitation and of a reduced vagal modulation, which was more evident in patients with an anterior localization early after AMI.
Asunto(s)
Frecuencia Cardíaca , Infarto del Miocardio/fisiopatología , Electrocardiografía Ambulatoria , Frecuencia Cardíaca/fisiología , Humanos , Persona de Mediana Edad , Sistema Nervioso Simpático/fisiopatología , Factores de TiempoRESUMEN
The paper describes the case of a patients suffering from a pre-excitation syndrome who underwent numerous episodes of reciprocal tachycardia during pregnancy. The clinical implications and various methods of therapy used are discussed.
Asunto(s)
Complicaciones Cardiovasculares del Embarazo/diagnóstico , Taquicardia Paroxística/diagnóstico , Síndrome de Wolff-Parkinson-White/diagnóstico , Enfermedad Aguda , Adulto , Terapia Combinada , Electrocardiografía , Femenino , Humanos , Embarazo , Complicaciones Cardiovasculares del Embarazo/terapia , Taquicardia Paroxística/terapia , Síndrome de Wolff-Parkinson-White/terapiaAsunto(s)
Atenolol/administración & dosificación , Clortalidona/administración & dosificación , Hipertensión/tratamiento farmacológico , Propanolaminas/administración & dosificación , Adulto , Anciano , Combinación de Medicamentos/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
To study effects on pituitary-adrenocortical activity of a sustained block of angiotensin II formation, six 'drug-resistant' patients with essential hypertension were studied before and during treatment with an inhibitor of the angiotensin-converting enzyme (Captopril, SQ 14,225). The drug was given in increasing doses (100-400 mg/day) for 2 weeks whilst patients received a moderately restricted sodium intake (60-80 mmol/day). Immunoreactive ACTH, cortisol, aldosterone, plasma renin activity (PRA) and the activity of the angiotensin-converting enzyme (ACE) were measured in blood samples drawn at 0800-0900 h. Urinary excretion of cortisol and aldosterone were measured in 24-h urine collections. Further information on pituitary-adreno-cortical function was obtained by measuring serial plasma corticosteroid levels after submaximal stimulation with a synthetic ACTH preparation. ACTH and cortisol did not change an observation which does not support the hypothesis that glucocorticoid activity is influenced by a decrease in plasma angiotensin II concentrations.