RESUMEN
A patient with very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is reported. He had a severe neonatal presentation and cardiomyopathy. He was found to be homozygous for a severe mutation with no residual enzyme activity. Tandem mass spectrometry on dried blood spots revealed increased long chain acylcarnitines. VLCAD enzyme activity was severely decreased to 2% of control levels. Dietary management consisted of skimmed milk supplemented with medium chain triglycerides and L-carnitine. Outcome was good and there was no acute recurrence.
Asunto(s)
Acil-CoA Deshidrogenasa de Cadena Larga/deficiencia , Cardiomiopatías/enzimología , Homocigoto , Acil-CoA Deshidrogenasa de Cadena Larga/genética , Cardiomiopatías/dietoterapia , Cardiomiopatías/genética , Estudios de Seguimiento , Humanos , Recién Nacido , Masculino , Espectrometría de Masas , Mutación , PronósticoRESUMEN
We used spectral analysis of heart rate variability (HRV) to study the effects of the calcium channel blockers diltiazem and nifedipine and the beta-blocker metoprolol on the sympathetic nervous system in patients following myocardial infarction. Energy in the low-frequency range (0.04 to 0.12 Hz) in the standing (tilt) position was used as a quantitative index of sympathetic activity. Twenty-seven male patients, mean age 62 +/- 13 years, were studied 2 to 6 weeks after myocardial infarction. Eight patients received metoprolol, 100 mg twice daily; nine patients received diltiazem, 60 mg three times daily; and 10 patients received nifedipine, 10 mg three times daily. HRV and arterial blood pressure were recorded before and 5 to 7 days after initiation of therapy. None of the drugs had significant effects on the systolic blood pressure, and only nifedipine significantly reduced the diastolic blood pressure. Metoprolol and diltiazem reduced the low-frequency HRV in all patients studied, but nifedipine had no consistent effects. Our results suggest that diltiazem had a depressant effect on sympathetic activity similar to beta-adrenergic blockers. This effect was not observed with nifedipine. The reduction in sympathetic activity by diltiazem may contribute to its therapeutic effects in the post-infarction period.