Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020440 (hypercapnia)
 7,939 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients with heart failure are known to demonstrate periodic respiration during sleep. The mechanism behind periodic respiration is thought to be related to left heart enlargement causing an increased transit time between lung and chemoreceptors leading to an oscillation of the feed back loop controlling respiration. Additionally hyperventilation was shown to play an important role. We report of an 18 year old patient with idiopathic dilated cardiomyopathy (left atrial 52 mm, left ventricular end diastolic diameter 69 mm). Polysomnography revealed prolonged transit time and periodic respiration with impaired sleep. Hypocapnia and hyperventilation was demonstrated. Following successful cardiac transplantation periodic respiration was absent and transit time was normal. There was no hypocapnia or hyperventilation. Hypercapnic ventilatory response did no change. These findings support the model of an oscillation of the feed back loop controlling respiration as the main pathomechanism behind periodic respiration.
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PMID:[Elimination of periodic respiration in heart failure by heart transplantation]. 767 58

Patients with heart failure are known to demonstrate periodic respiration (PR) during sleep. The factors causing PR are not well known. We therefore studied 20 patients (aged 18-66 years) with idiopathic dilated cardiomyopathy. Full-night polysomnography and evaluation of respiration and transcutaneous oxygen saturation were performed. Hypercapnic ventilatory response (HCVR) was evaluated during daytime. The patients showed PR for 25 +/- 26% (mean +/- standard deviation) of total sleep time. During PR, oxygen desaturated 7.1 +/- 4.6%. Sleep was impaired. HCVR was normal. Oxygen desaturation during PR was predicted by HCVR (r = 0.47, P < 0.05) and left atrial diameter (r = 0.60, P < 0.05). The time period of PR expressed as a fraction of total sleep time was correlated with HCVR (r = 0.45, P < 0.05) and left atrial diameter (r = 0.51, P < 0.05). In conclusion, PR with oxygen desaturation, arousals, and impaired sleep was observed in stable heart failure. HCVR and left heart dimensions were related to PR. These findings confirm the concept of a feedback loop describing respiratory control in PR.
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PMID:Periodic respiration in patients with heart failure. 847 14