Primary stent treatment for acute evolving myocardial infarction Tratamiento primario con stent en la fase aguda del infarto de miocardio

Abstract

Introduction. Although direct balloon angioplasty has emerged as an alternative to thrombolytic therapy in patients with acute myocardial infarction, reocclusion and restenosis rates are limiting factors. We postulated that these limitations could be partly overcome by primary stenting of the responsible lesion. Material and methods. Since January/94 we have studied 59 patients with acute myocardial infarction who were treated in the early phase (3.1 ±2 hours since the onset of symptoms) by elective Palmaz-Schatz stent implantation. No adjunctive thrombolytic therapy was associated. Two patients were in cardiogenic shock and were treated under percutaneous cardiopulmonary support. At cardiac catheterization a left ventriculography and coronary angiograms were obtained. Then, mechanical recanalization of the responsible lesion was performed. If the angiographic anatomy was considered suitable, a stent was implanted at the lesion. Results. The infarct related artery was the left anterior descending in 29 patients, the circunflex in 14 and the right coronary artery in 16. At baseline conditions, 40 patients had a totally occluded artery and 19 showed a TIMI-grande 1 antegrade flow. One patient had an early clinical recurrence 4 days later, which required an additional divided Palmaz-Schatz stent at the distal portion of the lesion, in order to seal a residual dissection. All remaining patients had a favourable clinical course without major complications. Immediately after treatment the minimal lumen diameter was 3.2 ± 0.4 mm and no residual stenosis was detectable at the treated segment. Six-month angiographie reevaluation was performed in all 29 (49%) eligible patients. Restenosis (> 50% stenosis) was detected in 6 out of the 29 evaluated patients (21%). Conclusions. Primary stent implantation in selected patients with an evolving myocardial infarction provides good initial and 6-month results.