Table 1. Criteria for diagnosing vasospastic angina.

1. Nitrate-responsive angina (during a spontaneous episode, with at least one of the following)

a. Rest angina, especially between night and early morning

b. Marked diurnal variation in exercise tolerance, reduced in morning

c. Hyperventilation can precipitate an episode

d. Calcium channel blockers (but not beta-blockers) suppress episodes

(2) Transient ischemic ECG changes (during a spontaneous episode, including any of the following in at least two contiguous leads)

a. ST-segment elevation ≥0.1 mV

b. ST-segment depression ≥0.1 mV

c. New negative U waves

(3) Coronary artery spasm

a. Defined as transient total or subtotal coronary artery occlusion (>90% constriction) with angina

b. Ischemic ECG changes either spontaneously or in response to a provocative stimulus (typically acetylcholine, ergot, or hyperventilation)