To the Editor:
In a recent issue of theEuropean Respiratory Journal, Buchneret al.[1] reported an alleviation of sleep apnoea in 40 patients with acute myocardial infarction (AMI) 12 weeks after the event, associated with an improvement of ≥5% in the ejection fraction (EF). Moderate to severe sleep apnoea was observed in 55% of the patients. At the second evaluation the respiratory events were reduced significantly more in the improved EF group. The authors' novel observation was that the decrease in the apnoea–hypopnoea index (AHI) was the result of a reduction in obstructive, but not central respiratory events.
Our own study of the time course of sleep apnoea after a first AMI was published several months earlier in theJournal of Clinical Sleep Medicine[2], although it was not cited by Buchneret al.[1]. The study included 52 patients with first-ever acute coronary syndrome (ACS) who underwent polysomnography (PSG) on the third day after the acute cardiac event and were re-evaluated with PSG 1 …