Subject(s)
Natriuretic Peptide, Brain/blood , Ventricular Dysfunction, Left/diagnosis , Aged , Aged, 80 and over , Area Under Curve , Biomarkers/blood , Female , Humans , Male , Predictive Value of Tests , Stroke Volume , Ventricular Dysfunction, Left/blood , Ventricular Dysfunction, Left/physiopathologyABSTRACT
BACKGROUND: Cheyne-Stokes respiration disrupts sleep, leading to daytime somnolence and cognitive impairment. It is also an independent marker of increased mortality in heart failure. This study evaluated the effectiveness of oxygen therapy for Cheyne-Stokes respiration in heart failure. METHODS: Eleven patients with stable heart failure and Cheyne-Stokes breathing were studies. Oxygen and air were administered for 4 weeks in a double-blind, cross-over study. Sleep and disordered breathing was assessed by polysomnography. Symptoms were assessed using the Epworth Sleepiness Scale, visual analogue and quality of lift scores. Cognitive function was assessed by neuropsychometric testing. Overnight urinary catecholamine excretion was used as a measure of sympathetic nerve activity. RESULTS: Ninety-seven percent of apnoeas were central in origin. Oxygen therapy reduced the central apnoea rate (18.4 +/- 4.1 vs 3.8 +/- 2.1 per hour; p = 0.05) and periodic breathing time (33.6 +/- 7.4 vs 10.7 +/- 3.9% of actual sleep time; p = 0.003). Oxygen did not improve sleep quality, patient symptoms or cognitive failure. Oxygen reduced urinary noradrenaline excretion (8.3 +/- 1.5 vs 4.1 +/- 0.6 nmol.mmol-1 urinary creatinine; p = 0.03). CONCLUSION: Oxygen stabilized sleep disordered breathing and reduced sympathetic activity in patients with heart failure and Cheyne-Stokes respiration. We were unable to demonstrate an effect on either patient symptoms or cognitive function.
Subject(s)
Arousal/physiology , Cheyne-Stokes Respiration/therapy , Heart Failure/therapy , Neuropsychological Tests , Oxygen Inhalation Therapy , Polysomnography , Sleep Stages/physiology , Aged , Cheyne-Stokes Respiration/physiopathology , Creatinine/urine , Cross-Over Studies , Double-Blind Method , Female , Heart Failure/physiopathology , Humans , Male , Middle Aged , Norepinephrine/urine , Sympathetic Nervous System/physiopathologyABSTRACT
Matched maternal venous (MV), umbilical artery (UA) and umbilical vein (UV) concentrations of atrial natriuretic peptide [ANP] were measured in 36 normotensive women at term delivery (23 vaginal, 13 caesarean) and 17 non-pregnant women in the first half of the menstrual cycle. MV [ANP] at caesarean section was similar to that in non-pregnant women, but UA and UV [ANP] were higher (P less than 0.01 for both). UA, but not UV, [ANP] was markedly raised after vaginal delivery. Plasma concentrations of aldosterone [ALD] were measured in 16 of the matched sets of samples. No statistically significant association was found between [ANP] and [ALD] in either maternal or fetal samples. Neither maternal nor fetal [ANP] correlated with serum Na+ or osmolality, haematocrit, blood pressure or heart rate.
