Obstructive sleep apnea manifesting as suspected angina: report of three cases

To describe three cases of obstructive sleep apnea that resembled coronary artery disease and to suggest features that might distinguish these two syndromes.

We present three detailed case reports of patients with severe obstructive sleep apnea and discuss similar cases from the literature.

Two obese women and one obese man with previously undiagnosed obstructive sleep apnea had chest discomfort, episodic dyspnea, and palpitations, most prominent at night. All three patients had multiple cardiac risk factors and had previously undergone cardiac evaluations, including at least two prior cardiac catheterizations each. Repeated cardiac catheterization revealed less coronary occlusive disease than expected on the basis of the symptoms in all three patients and a small atrial septal defect in one patient. When reassessed, the medical histories suggested obstructive sleep apnea.

Overnight polysomnography documented the presence of severe sleep apnea; the three patients had mean values of 56 disordered breathing events per hour and 44% minimal oxygen saturation. Although bi-level or continuous positive airway pressure yielded initial improvement, all patients had difficulty with routine use of this therapy after 1 1/2 years of follow-up.

The initial manifestations of severe obstructive sleep apnea may simulate angina, suggest arrhythmia, or mimic heart failure. Failure to inquire about snoring and daytime somnolence in patients with chest pain may prevent the identification of clinically significant disordered breathing during sleep.