Coronary heart disease and upper airway obstruction.

Coronary heart disease (CHD) is a leading cause of death among middle-aged men. In the same age group the spectrum of upper airway obstruction from habitual snoring to obstructive sleep apnoea syndrome (OSAS) is frequent. In several studies snoring was found to be an important risk factor for ischaemic heart disease. The prevalence of OSAS in patients with CHD, profile of risk factors and ventricular arrhythmias was determined in a prospective manner in 78 patients with stenosis of one or more coronary arteries at coronary arterography. OSAS was found in 27 patients (34.6%). Mean respiratory disturbance index (RDI) was 23.9. RDI increased with higher age. No significant differences in both groups could be found in ventricular arrhythmias, left ventricular ejection fraction and risk factors, except hyperuricaemia and adiposity. OSAS is frequent in patients with CHD and may be an additional risk factor besides the known coronary risk factors. Patients with the combination of CHD and OSAS have to be regarded as a group at particular risk because of several interactions between OSAS and coronary haemodynamics. Furthermore the microstructure of sleep in patients with nocturnal myocardial ischaemia is disturbed.