Evidence in favor of the vasospastic cause of coronary artery thrombosis.

Evidence is presented which suggests that it is likely that vasospasm initiates coronary artery thrombosis. Spasm causes a violet constriction of the vessel and also produces stasis, and both factors are implicated in the thrombotic process. Spasm can occur in sclerotic segments, and intimal tears and plaque ruptures in arteriosclerotic plaques are attributed to spasm. The thrombus forms over the intimal disruption, abetted by the stasis of spasm. In arteries with mild or no intimal injury, continuing stasis over a period of time is considered as the major factor in thrombus formation. This ongoing stasis is attributed to an injury-spasm reaction to necrotic muscle, and probably is equivalent to the "no-reflow" phenomenon of infarction.