Late (> 48 hr) myocardial infarction after PTCA: Clinical and angiographiccharacteristics of infarction related or not to the angioplasty site

Since late myocardial infarctions after percutaneous coronary interventions have not been well characterized, we intended to evaluate the characterist ics of myocardial infarctions occurring > 48 hr after balloon angioplasty o f native coronary arteries or saphenous vein grafts. The Montreal Heart Ins titute database (1985-1996) was interrogated for all patients readmitted wi th a diagnosis of MI more than 48 hr after successful percutaneous translum inal coronary angioplasty (PTCA). We compared the clinical, procedural, and angiographic variables between Mis related or not to the index PTCA site. One hundred and ninety-three patients presented with late myocardial infarc tion (MI) following balloon angioplasty. The median time elapsed between PT CA and MI was 55 days compared to 968 days when MI was unrelated to the PTC A site. Mis related to the PTCA site were more likely non-Q-wave (76% vs. 3 5%, P = 0.0001) with less marked OK-MS rise. Angiography showed less comple x lesions (63% vs. 90%, P = 0.001) and better thrombolysis in myocardial in farction (TIMI) grade flow (TIMI II to III, 66% vs. 56%, P = 0.01) when the culprit lesion was at the PTCA site. Independent predictors of MI at the P TCA site were vein graft dilation, female sex, and residual stenosis post-P TCA. Myocardial infarctions occurring late after PTCA have a distinct time course and present specific characteristics according to their relationship or not to the previously dilated site. (C) 2001 Wiley-Liss, Inc.