Typically, these presentations reflect the development of a heart attack and/or a potentially lethal heart arrhythmia; they require immediate medical intervention as well as consideration for the presence of, and specific treatment regimens for, their disorder.Variant angina should be suspected by a cardiologist when a) an individuals symptoms occur at rest or during sleep; b) an individuals symptoms occur in clusters; c) an individual with a history of angina does not develop angina during treadmill stress testing (variant angina is exercise tolerant); d) an individual with a history of angina shows no evidence of other forms of cardiac disease; and/or e) an individual without features of coronary artery atherosclerotic heart disease has a history of unexplained fainting.Complaints of chest pain should be immediately checked for an abnormal electrocardiogram (ECG). ECG changes compatible but not indicative of variant angina include elevations rather than depressions of the ST segment or an elevated ST segment plus a widening of the R wave to create a single, broad QRS complex peak termed the "monophasic curve". Associated with these ECG changes, there may be small elevations in the blood levels of cardiac damage marker enzymes, especially during long attacks. Some individuals with otherwise typical variant angina may show depressions, rather than elevations in the ST segments of their ECGs during angina pain; they may also show new U waves on ECGs during angina attacks.A significant percentage of those with variant angina have symptom-free episodes of coronary artery spasm. These episodes may be far more frequent than expected, cause myocardial ischemia (i.e.
However, individuals with atherosclerosis-related unstable angina may similarly exhibit night to early morning hour symptoms that are unrelated to exertion.Cardiac examination of individuals with variant angina is usually normal in the absence of current symptoms. Two-thirds of these individuals do have concurrent atherosclerosis of a major coronary artery, but this is often mild or not in proportion to the degree of their symptoms. Persons who have atherosclerosis-based occlusion that is ≥70% in a single coronary artery or that involves multiple coronary arteries are predisposed to develop a variant angina form that has a poorer prognosis than most other forms of this disorder. In these individuals but also in a small percentage of individuals without appreciable atherosclerosis of their coronary arteries, attacks of coronary artery spasm can have far more serious presentations such as fainting, shock, and cardiac arrest.