High prevalence and persistence of sleep apnoea in patients referred for acute left ventricular failure and medically treated over 2 months.
AIMS: Cardiac failure patients were studied systematically using polysomnography 1 month after recovering from acute pulmonary oedema, and again after 2 months of optimal medical treatment for cardiac failure. METHODS AND RESULTS: This prospective study of consecutive patients was conducted in a cardiac care unit of a university hospital. V o(2)measurements and left ventricular ejection fraction were recorded. Thirty-four patients, initially recruited with pulmonary oedema, improved after 1 month of medical treatment to NYHA II or III. They were aged less than 75 years and had a left ventricular ejection fraction less than 45% at the time of inclusion. Age was 62 (9) years, body mass index= 27 (5) kg x m(-2)and an ejection fraction= 30 (10)%. Eighteen of the 34 patients (53%) had coronary artery disease. Twenty-eight of the 34 had sleep apnoea syndrome with an apnoea+hypopnoea index >15 x h(-1)of sleep. Thus, the prevalence of sleep apnoea in this population was 82%. Twenty-one of 28 (75%) patients had central sleep apnoea and seven of 28 (25%) had obstructive sleep apnoea. Patients with central sleep apnoea had a lower Pa co(2)than those with obstructive sleep apnoea (33 (5) vs 37 (5) mmHg, P<0.005). Significant correlations were found between apnoea+hypopnoea index and peak exercise oxygen consumption (r= -0.73, P<0.01), and apnoea+hypopnoea index and Pa co(2)(r= -0.42, P = 0.03). When only central sleep apnoea patients were considered, a correlation between apnoea+hypopnoea index and left ventricular ejection fraction was also demonstrated (r= -0.46, P<0.04). After 2 months of optimal medical treatment only two patients (both with central sleep apnoea) showed improvement (apnoea+hypopnoea index <15 x h(-1)). CONCLUSIONS: We have demonstrated a high prevalence of sleep apnoea, which persisted after 2 months of medical treatment, in patients referred for acute left ventricular failure. Central sleep apnoea can be considered a marker of the severity of congestive heart failure. (+info)
An investigation into the changes in airway dimension and the efficacy of mandibular advancement appliances in subjects with obstructive sleep apnoea.
This prospective clinical study evaluates a group of 37 male Caucasians with obstructive sleep apnoea for changes in airway dimension and the efficacy associated with the use of mandibular advancement splints. Lateral skull radiographs were obtained with the subjects--upright in occlusion, supine in occlusion, and supine in protrusion. Each radiograph was traced and digitized, and changes in mandibular position, airway dimensions, and hyoid were examined. Subjects were invited to complete pre- and post-treatment questionnaires, and interviewed following fitting of a removable Herbst mandibular advancement splint. Significant changes were recorded in the airway dimensions in response to both a change in position, from upright to supine, and in response to mandibular advancement. A compliance rate of 76 per cent was achieved with no reported serious complications associated with the use of mandibular advancement devices. (+info)
Nocturnal ischemic events in patients with obstructive sleep apnea syndrome and ischemic heart disease: effects of continuous positive air pressure treatment.
OBJECTIVES: To investigate the occurrence of nocturnal ischemic events in patients with obstructive sleep apnea syndrome (OSAS) and ischemic heart disease (IHD). BACKGROUND: Although previous reports documented nocturnal cardiac ischemic events among OSAS patients, the exact association between obstructive apneas and ischemia is not yet clear. It is also not known what differentiates between patients showing nocturnal ischemia and those that do not. METHODS: Fifty-one sleep apnea patients (age 61.3+/-8.3) with IHD participated in the study (after withdrawal of beta-adrenergic blocking agents and anti-anginotic treatment). All patients underwent whole-night polysomnography including ambulatory blood pressure recordings (30 min interval) and continuous Holter monitoring during sleep. A control group of 17 OSAS patients free from IHD were also similarly studied. Fifteen of the 51 patients were also recorded under continuous positive airway pressure (CPAP). RESULTS: Nocturnal ST segment depression occurred in 10 patients (a total of 15 events, 182 min), of whom six also had morning ischemia (06-08 am). Five additional patients had only morning ischemia. No ischemic events occurred in the control group. Age, sleep efficiency, oxygen desaturation, IHD severity and nocturnal-double product (DP) values were the main variables that significantly differentiated between patients who had ischemic events during sleep and those who did not. Nocturnal ischemia predominantly occurred during the rebreathing phase of the obstructive apneas, and it is characterized by increased heart rate (HR) and DP values. Treatment with continuous positive airway pressure significantly ameliorated the nocturnal ST depression time from 78 min to 33 min (p<0.001) as well as the maximal DP values (14,137+/-2,827 vs. 12,083+/-2,933, p<0.001). CONCLUSIONS: Exacerbation of ischemic events during sleep in OSAS may be explained by the combination of increased myocardial oxygen consumption as indicated by increased DP values and decreased oxygen supply due to oxygen desaturation with peak hemodynamic changes during the rebreathing phase of the obstructive apnea. Treatment with CPAP ameliorated the nocturnal ischemia. (+info)
Obstructive sleep apnea.
Obstructive sleep apnea is a significant medical problem affecting up to 4 percent of middle-aged adults. The most common complaints are loud snoring, disrupted sleep and excessive daytime sleepiness. Patients with apnea suffer from fragmented sleep and may develop cardiovascular abnormalities because of the repetitive cycles of snoring, airway collapse and arousal. Although most patients are overweight and have a short, thick neck, some are of normal weight but have a small, receding jaw. Because many patients are not aware of their heavy snoring and nocturnal arousals, obstructive sleep apnea may remain undiagnosed; therefore, it is helpful to question the bedroom partner of a patient with chronic sleepiness and fatigue. Polysomnography in a sleep laboratory is the gold standard for confirming the diagnosis of obstructive sleep apnea; however, the test is expensive and not widely available. Home sleep studies are less costly but not as diagnostically accurate. Treatments include weight loss, nasal continuous positive airway pressure and dental devices that modify the position of the tongue or jaw. Upper airway and jaw surgical procedures may also be appropriate in selected patients, but invasiveness and expense restrict their use. (+info)
Transtracheal air in the treatment of obstructive sleep apnoea hypopnoea syndrome.
A 49 year old woman with typical obstructive sleep apnoea hypopnoea syndrome underwent an unsuccessful trial with continuous positive airway pressure (CPAP) followed by uvulopalatopharyngoplasty with septorhinoplasty, treatment with protriptyline, and a second CPAP trial that was abandoned. Transtracheal air was then given and normalised sleep and breathing at a flow rate of 5 l/min. A sustained clinical improvement was observed at follow up visits. Transtracheal air could represent a simple and effective alternative to tracheotomy in patients with obstructive sleep apnoea hypopnoea syndrome in whom conventional treatments fail. (+info)
Protruding the tongue improves posterior rhinomanometry in obstructive sleep apnoea syndrome.
In posterior rhinomanometry (PRM), oropharyngeal pressure is measured using a tube placed between the tongue and the hard palate. For valid results the patient must position the tongue and soft palate so that both the oropharynx and nasopharynx remain open. A high rate of failure of conventional PRM has been reported in normal individuals. In patients with obstructive sleep apnoea syndrome (OSAS), upper airway abnormalities may further increase the failure rate. This study proposes a modification of the technique in which protrusion of the tongue enhances pressure transmission between the nasopharynx and the mouth. In eight normal subjects, resistance was similar when measured by both methods. Of 24 OSAS patients, conventional PRM was unsuccessful in 11. In the remaining 13 patients, a significant correlation between the two methods was found, but resistance was lower by "tongue-out" than by conventional PRM, consistent with a decrease, during tongue protrusion, in retropalatal resistance, which is a component of the "nasal" resistance measured by PRM. In 26 OSAS patients, unilateral nasal resistance values measured by "tongue-out" PRM were similar to those measured by anterior rhinomanometry. When the "tongue-out" method was used routinely in 541 snorers, failure rates were 1.1% in the 272 non-OSAS patients and 3.7% in the 269 OSAS patients. These results indicate that posterior rhinomanometry with tongue protrusion is a highly effective tool for measuring nasal resistance in snorers. (+info)
Effect of continuous positive airway pressure on blood pressure : a placebo trial.
This study examined the effect of continuous positive airway pressure (CPAP) treatment on blood pressure in patients with obstructive sleep apnea. Thirty-nine patients with sleep apnea were studied. Ambulatory blood pressure monitoring was obtained before and after patients were randomized to receive either 1 week of CPAP or placebo CPAP (CPAP administered at ineffective pressure). Blood pressure was examined over daytime hours (6 AM to 10 PM) and during nighttime hours (10 PM to 6 AM). Daytime mean arterial blood pressure decreased significantly but equally in both the active treatment group and the placebo treatment group (P=0.001). Nighttime mean arterial pressure levels decreased to a much greater extent over time in the patients who received active CPAP treatment (P=0. 032). CPAP does appear to decrease nighttime blood pressure. However, the decrease in daytime blood pressure may reflect a nonspecific response (ie, placebo), since both the active treatment group and the placebo treatment group developed comparable decreases in blood pressure. (+info)
Ventilatory decline after hypoxia and hypercapnia is not different between healthy young men and women.
The gradual decay in ventilation after removal of a respiratory stimulus has been proposed to protect against cyclic breathing disorders such as obstructive sleep apnea (OSA). The male predominance of OSA, and the increased incidence of OSA in women after menopause, indicates that the respiratory-stimulating effect of progesterone may provide protection against OSA by altering the rate of poststimulus ventilatory decline (PSVD). It was therefore hypothesized that PSVD is longer in premenopausal women than in men and is longer in the luteal menstrual phase compared with the follicular phase. PSVD was measured in 12 men and in 11 women at both their luteal and follicular phases, after cessation of isocapnic hypoxia and normoxic hypercapnia. PSVD was compared between genders and between women in the luteal and follicular phases by repeated-measures ANOVA. There were no significant differences in PSVD between any of the groups after either respiratory stimulus. This suggests that the higher occurrence of OSA in men does not reflect an underlying gender difference in PSVD and implies the increased prevalence of OSA in women after menopause is not representative of an effect of progesterone on PSVD. (+info)