Coronary arteriography in 300 patients within one year of onset of symptoms of coronary arterial disease revealed already severe anatomical coronary disease in three patient groups: those with angina pectoris alone (164 patients), with subendocardial myocardial infarction (63 patients), and with transmural myocardial infarction (73 patients). The number of vessels diseased (larger than or equal to 50% obstruction), distribution of obstruction, and degree of stenosis were similar in the three groups. However, total occlusion of at least one artery was much more common in transmural myocardial infarction and in subendocardial myocardial infarction with elevation of enzyme levels. We suggest that such occlusions occurred at the time of the infarction. Similarities in coronary anatomy between patient subgroups with angina (on exercise or at rest and nocturnal) indicate that factors other than coronary anatomy intervene in precipitating the different types of angina. Vessel disease was not related to smoking, hyperlipidaemia, or hypertension but coronary disease was manifest earlier in life in smokers or those with hyperlipidaemia.