Читать книгу Practical Cardiovascular Medicine - Elias B. Hanna - Страница 221

While Prinzmetal angina was initially described in patients who had underlying obstructive CAD, sometimes unstable CAD,^4,5,115,116 later reports suggest that vasospasm is also commonly diagnosed in patients with typical angina and no obstructive CAD.⁶ Even when the coronary arteries appear angiographically normal, IVUS imaging demonstrates that the sites of vasospasm exhibit underlying atherosclerosis. Atherosclerosis induces endothelial dysfunction and dysregulation of nitric oxide production, which leads to local vascular hyperreactivity.⁷

Vasospasm may be epicardial and focal, i.e., involving one coronary segment, or epicardial and diffuse, involving two or more coronary segments. It may also occur solely at the microvascular level.

Additional features of vasospasm:

 Epicardial vasospasm often involves one site and recurs at the same atherosclerotic site; less commonly, it may involve multiple sites, sometimes two separate coronaries, or occur at separate sites at different times (~15% of cases).¹¹⁷

 The LAD and RCA are most involved. The proximal and distal segments have been variously involved in different reports.

 In the absence of CAD, spontaneous remissions within 6–12 months of follow-up or remissions with CCBs are common (up to 83% of patients). Yet up to a third of these patients may experience recurrences.116-119

 Vasospasm that occurs without significant CAD is more commonly seen in women,6,120,121 although some series suggest it is more common in men.115, 116, 119 It is generally described in patients >40 years of age, with a mean age of 55–65, and is more prevalent among Asian populations. Smoking and chronic alcohol or cocaine use increase the risk of vasospasm.