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.
Individuals presenting with potentially lethal irregularities in the rhythm of their heart beating or a history of episodic fainting spells due to such arrhythmias require implantation of an internal defibrillator and/or cardiac pacemaker to stop such arrhythmias and restore normal heart beating. Other rare but severe complications of variant angina viz., myocardial infarction, severe congestive heart failure, and cardiogenic shock require the same immediate medical interventions that are used for other causes of these extremis conditions. In all of these emergency cases, percutaneous coronary intervention to stent areas where coronary arteries evidence spasm is only useful in individuals who have concomitant coronary atherosclerosis on coronary angiogram. Prognosis
Most individuals with variant angina have a favorable prognosis provided they are maintained on calcium channel blockers and/or long-acting nitrates; five-year survival rates in this group are estimated as over 90%. The Japanese Coronary Spasm Association established a clinical risk scoring system to predict outcomes for variant angina. Seven major factors (i.e. history of out of hospital cardiac arrest [score = 4]; smoking, angina at rest, physically obstructive coronary artery disease, and spasm in multiple coronary arteries [score = 2]; and presence of ST segment elevations on ECG and history of using beta blockers [score = 1]) where assigned the indicated scores. Individuals with scores of 0 to 2, 3 to 5, and ≥6 experienced an incidence of a major cardiovascular event in 2.5, 7.0, and 13.0% of cases.