resistance, to the efficacy of continuously used long-acting nitroglycerin formulations. One strategy to avoid this development is to schedule nitroglycerin-free periods of between 12 and 14 hours between doses of long-acting nitroglycerin formulations. Individuals whose symptoms are poorly controlled by a calcium blocker may benefit from addition of a long-acting nitroglycerin and/or a second calcium channel blocker of a different class than the blocker already in use. Nevertheless, about 20% of individuals fail to respond adequately to the two-drug calcium blocker plus long-acting nitroglycerin regimen. If these individuals have significant permanent occlusion of their coronary arteries, they may benefit by stenting their occluded arteries. However, coronary stenting is contraindicated in drug- refractory individuals who do not have significant organic occlusion of their coronary arteries. For the latter individuals, other, less fully investigated drugs may provide symptom relief. Statins, e.g. fluvastatin, while not evaluated in large-scale double-blind studies, are reportedly helpful in reducing variant angina attacks and should be considered in patients when calcium channel blockers and nitroglycerin fail to achieve good results. There is also interest in using rho-kinase inhibitors, such as fasudil (available in Japan and China but not the USA), and blocker of alpha-1 adrenergic receptors such as prazosin (which when activated cause vasodilation) but studies are needed to support their clinical utility in variant angina. Emergency
Individuals with certain severe complications of variant angina require immediate therapy.
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.