Vasospastic Angina

Vasospastic angina is episodic myocardial ischaemia caused by a temporary fall in coronary blood supply, not by a fixed inability to increase flow during exertion. A coronary artery can constrict severely, then return to its previous calibre; this explains why attacks often occur at rest and why angiography may look normal between episodes. “Prinzmetal angina” and “variant angina” remain useful legacy terms, but vasospastic angina is the preferred current term. The endotype may involve epicardial spasm, microvascular spasm, or both. Microvascular spasm can produce pain and ischaemic ECG changes without the greater than 90% epicardial narrowing used in the COVADIS definition of epicardial spasm. The experienced nurse looks first for the timing of pain, obtains the ECG while symptoms are present, and treats persistent or unstable chest pain as a possible acute coronary syndrome until infarction and other dangerous causes have been excluded. A normal ECG after the episode is over does not erase the earlier ischaemia.