Stent implantation in acute myocardial infarction

Among 138 patients treated with coronary angioplasty during acute myocardial infarction (AMI), 35 (25%) had stent implantation. Mean age was 56 years and 83% were men. Mean onset of chest pain was 6.0 ± 5.3 hours, and previous thrombolytic therapy was given to 10 patients (29%). Infarct location was anterior in 19 (54%), inferior in 14 (40%), and lateral in 2 patients (6%). Thrombolysis In Myocardial Infarction trial flows 0, 1, and 2 were seen in 24 (69%), 6 (17%), and 5 patients (14%), respectively. The culprit vessel was the left anterior descending artery in 18 (51%), right coronary artery in 14 (40%), left circumflex in 2 (6%), and left main coronary artery in 1 patient (3%). Mean vessel diameter was 3.3 ± 0.3 mm. Indications were: primary in 5 (14%), suboptimal result in 8 (23%), nonocclusive dissection in 14 (40%), and occlusive dissection in 8 patients (23%). Angiographic thrombus after initial angioplasty was present in 12 patients (34%). A total of 46 stents were implanted; mean balloon diameter and pressure were 3.4 ± 0.4 mm and 15.5 ± 2.2 atm, respectively. Residual diameter stenosis was 4 ± 7%. There were 2 deaths: sudden in I, and after elective coronary artery bypass grafting in the other; 2 patients (6%) had groin hematomas. Mean hospitalization was 9.9 ± 5.0 days. Repeat angiography revealed no stent occlusion. With initial intravenous heparin for 3 to 7 days, all patients received aspirin and ticlopidine for 1 month. Thus, AMI is not a contraindication for stent implantation. The benefits of stenting are a high success rate, low residual diameter stenosis, and low incidence of in-hospital recurrent ischemia. Reduction in restenosis rate in this setting is likely but remains to be determined.