Читать книгу Practical Cardiovascular Medicine - Elias B. Hanna - Страница 222

Vasospasm usually leads to a more severe ischemia than fixed stenosis and is occlusive or subtotally occlusive, particularly when it occurs on top of obstructive, fixed stenosis. It typically leads to transient ST elevation, reflecting transmural ischemia, but it may also lead to ST-segment depression when the spasm is not totally occlusive. Post-ischemic T-wave inversion may be seen. Since ischemia may be severe, serious arrhythmias (VT, VF, AV block), syncope, sudden death, or MI may be seen. The combined risk of the latter complications is ~20% at several years of follow-up, even in the absence of CAD;^116-119 yet, spontaneous remissions (~40%) or remissions with CCBs (83%) are common, and the course is often, but not always, benign.

Angina is most commonly a rest angina without exertional limitation, even in patients with CAD (angina manifests when the dynamic component exaggerates the fixed stenosis).^5,117,118 It may also be a mixed rest/exertional angina, or, less commonly, a purely exertional angina.^{6,119,120,121} The rest angina typically follows a cyclic, often nocturnal pattern, and is more prolonged and more severe than classic angina; emotional stress is a common trigger.

Exercise ECG testing is frequently positive in these patients (50–70%),^5,6 partly from the underlying CAD, and partly from exercise- induced vasospasm.