Influence of late reopening of the infarct-related artery on left ventricular remodelling after myocardial infarction

Aim This trial was undertaken to assess the impact of late reopening of the infarct-related artery on left ventricular remodelling in post-myocardial infarction patients. Methods One hundred and fifty seven patients with recent myocardial infarction were routinely submitted to delayed (second week) catheterization. They also underwent systematic angioplasty of a significantly narrowed infarct-related artery with a suitable anatomy, or reopening of a totally occluded infarct-related artery, and repeat follow-up catheterization after 4 months. Changes in left ventricular ejection fraction, left ventricular volumes, and percent of regional hypokinesia were assessed over the study period. Results One hundred and thirty-two patients had two interpretable left ventriculograms and two interpretable coronary angiograms. At initial angiography, 56 out of 96 patients with a patent infarct-related artery were successfully submitted to percutaneous coronary angioplasty, of whom 25 had restenosis and eight had total reocclusion at follow-up angiography. Percutaneous transluminal coronary angioplasty was not attempted in the remaining 40 patients due to unsuitable anatomy in 18 or a nonsignificant lesion in 22. The infarct-related artery was totally occluded in 36 patients at initial angiography, and successfully reopened by means of angioplasty in 19, of whom seven showed a reocclusion at follow-up angiography. The independent predictors of left ventricular enlargement, identified by means of multivariate regression analysis, were initial stroke volume index 50 ml.m−2 (odds ratio=7·1, 95% confidence interval=[1·5; 25·8]), anterior infarct location (odds ratio=4·1, 95% confidence interval=[1·4; 11·5]) and reocclusion of the infarct-related artery (odds ratio=7·3, 95% confidence interval=[1·3; 27·3]). Angioplasty of a patent but significantly narrowed infarct-related artery was not found predictive. Conclusion This study demonstrates that reocclusion of a previously open infarct-related artery, as well as the initial low stroke volume index, enlarged end-systolic volume index and anterior infarct location are independent predictors of long-term left ventricular enlargement. These results emphasize the impact of long-term sustained patency of the infarct-related artery on the prevention of left ventricular dysfunction. The need for a larger randomized trial is recognised.