SUDDEN-DEATH AND MYOCARDIAL-INFARCTION DU E TO THROMBOSIS OF NORMAL CORONARY-ARTERIES - ANATOMIC STUDY OF 3 CASES

The anatomic lesions of two cases of sudden death (one man and one 24 years old woman) and of one case of rapidly fatal myocardial infarctio n (51 years old woman) are described. The coronary lesions were exclus ively thrombotic with no associated atherosclerosis or pre-existing ar terial wall change. The thrombi were occlusive from the outset or were constituted in successive mural stages, the last being occlusive and giving rise to the clinical symptoms (sudden death and/or myocardial i nfarction). Several points are discussed. The concept of normal corona ry artery must be confirmed by anatomic examination : coronary angiogr aphy is not sufficient for the diagnosis of dangerous atherosclerotic plaques which are not particularly stenotic, excentric, lipidic and fr agile. Thrombogenic factors are better understood and some may play a role in these cases of ''primary thrombosis'', be they of plasma or pl atelet origin. The trigger role of spasm cannot be ignored as some of the spastic and thrombotic factors are similar. The preferential coron ary site of these thromboses may be explained by constitutional change s (arterial hypolasia with narrow lumen) or acquired lesions (repeated arterial trauma due to shearing by the movements of the underlying le ft ventricle transmitted to the epicardial coronary arteries).