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Query: UMLS:C0037315 (
sleep apnea
)
8,000
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A 74-year-old man with
ischemic cardiomyopathy
was repeatedly admitted for congestive heart failure. His left ventricular ejection fraction was 21% and diastolic left ventricular dimension was 73.5mm by echocardiography. He was treated with biventricular pacing and heart failure improved from New York Heart Association class III to II. Before the treatment, brain natriuretic peptide was 600.5 pg/ml. Apnea hypopnea index was 23.8 and all events were central type. After biventricular pacing, apnea hypopnea index was improved to 21.9 after 11 days, 14.0 after 33 days, and 4.8 after 48 days. His left ventricular ejection fraction was 36%, diastolic left ventricular dimension was 71.4mm, and brain natriuretic peptide was 383.8 pg/ml. In this patient, central
sleep disordered breathing
was improved by biventricular pacing therapy after only 48 days.
...
PMID:[Improvement of central sleep disordered breathing with severe congestive heart failure by biventricular pacing therapy: a case report]. 1647 70
This paper examines the feasibility of accurate state classification of autonomic nervous activity (ANA) based on the power spectral pattern of the heart rate fluctuations (HRFs). Some attempts have been made to utilize artificial neural networks (ANNs) to classify HRFs for clinical diagnoses such as
ischemic cardiomyopathy
, arrhythmia or
sleep apnea
. To establish the firm bases for making such clinical diagnoses, it may be important to examine the classification accuracy for the data in physiologically well defined conditions by e.g. application of autonomic blocking agents. In this paper the three layered perceptron has been trained by the heart rate data in variety of ANS states yielded by the application of Atropine and Propranolol to 14 healthy male subjects. Six state (control, atropine and propranolol for each of the spine and upright posture) classification based on power spectrum showed average sensitivity of 67.2% and specificity 91.2%. Four state (control, atropine, propranolol and double block for either spine or upright posture) resulted in the average classification sensitivity of 75.7% and specificity 95.5%. The paper revealed that entropy bandwidth and indices originated from characteristic oscillations of blood pressure change improve the classification accuracy.
...
PMID:State classification of heart rate variability by an artificial neural network in frequency domain. 2109 42
Sleep apnea
is frequently observed in patients with heart failure (HF). In general,
sleep apnea
consists of two types: obstructive and central
sleep apnea
(OSA and CSA, respectively). OSA results from upper airway collapse, whereas CSA arises from reductions in central respiratory drive. In patients with OSA, blood pressure is frequently elevated as a result of sympathetic nervous system overactivation. The generation of exaggerated negative intrathoracic pressure during obstructive apneas further increases left ventricular (LV) afterload, reduces cardiac output, and may promote the progression of HF. Intermittent hypoxia and post-apneic reoxygenation cause vascular endothelial damage and possibly atherosclerosis and consequently coronary artery disease and
ischemic cardiomyopathy
. CSA is also characterized by apnea, hypoxia, and increased sympathetic nervous activity and, when present in HF, is associated with increased risk of death. In patients with HF, abolition of coexisting OSA by continuous positive airway pressure (CPAP) improves LV function and may contribute to the improvement of long-term outcomes. Although treatment options of CSA vary compared with OSA treatment, CPAP and other types of positive airway ventilation improve LV function and may be a promising adjunctive therapy for HF patients with CSA. Since HF remains one of the major causes of mortality in the industrialized countries, the significance of identifying and managing
sleep apnea
should be more emphasized to prevent the development or progression of HF.
...
PMID:Sleep apnea and heart failure. 2282 95