[Associated factors for sleep apnea in heart failure]. / Facteurs associés au syndrome d'apnées du sommeil dans l'insuffisance cardiaque.

OBJECTIVE: Genesis of sleep apnoea syndrome (SAS) in chronic heart failure (CHF) is not well known. The aim of our study was to find associated factors to SAS in heart failure (HF) and to look for differences between central sleep apnea (CSA) and obstructive sleep apnea (OSA). PATIENTS AND METHODS: We realised a cross-sectional and retrospective study. Thirty patients with stable heart failure under medical optimal therapy were included. Polygraphy, echocardiography and cardiopulmonary exercise were systematically performed. RESULTS: Men were predominant (80%) in the group. Mean age, left ventricular ejection fraction (LVEF) were respectively 64.1±13.8years and 40±9.8%. SAS was present in 60% of patients (33.3% were classified as central sleep apnoea [CSA] and 26.7% as obstructive sleep apnoea [OSA]). Body mass index, blood pressure and left ventricular pressures estimated by the E/Ea ratio were significantly higher in the group with SAS (P<0.05) compared to the non SAS group. New York Heart Association class was significantly higher (P=0.04) and the predicted peak VO(2) was significantly lower in CSA patients compared to OSA patients. CONCLUSION: High left ventricular pressures estimated by the E/Ea are significantly associated with SAS in heart failure. CSA patients tend to have a worse functional state than OSA patients.

[Diabetes and hypokinetic cardiopathy : when to consider mitochondrial disease?]. / Diabète et cardiopathie hypokinétique, quand évoquer une cytopathie mitochondriale ?

The association between diabetes mellitus and hypokinetic cardiomyopathy is frequent. We report a case of diabetes and hypokinetic cardiopathy in a 40-year-old man which led to the hypothesis of maternally inherited diabetes and deafness (MIDD) due to a mitochondrial disease. This diagnosis was confirmed by genetic testing which showed a DNA A3243G mutation in the mitochondria, the prevalence of which is 1-2% in diabetes mellitus. Cardiac abnormalities are frequent (18-34% of patients depending on the series) and the co-existence of left ventricular hypertrophy and systolic dysfunction is suggestive of this disease. Some authors have proposed co-enzyme Q as a treatment to improve the left ventricular ejection fraction and insulin secretion.