Coronary arteriographic findings soon after non Q wave myocardial infarction.

We performed early coronary arteriography in 27 patients (23 males, 4 females) having non Q wave MI. Infarct related vessel (IRV) was totally blocked in 25.9%, whereas 66.7% had severe residual stenosis (greater than or equal to 70%). Left main was involved in 7.5%, and at least 2 major coronary arteries were involved in 51.8%. Visible collaterals were seen in 11%. We feel, as compared to transmural MI, where total occlusion of IRV is common, the higher incidence of subtotal occlusion of IRV with severe residual stenosis, poor collaterals and significant involvement of at least one other major coronary artery may be responsible for observation of early recurrent ischemic episodes in non Q wave MI.