INFLUENCE OF LATE REOPENING OF THE INFARCT-RELATED ARTERY ON LEFT-VENTRICULAR REMODELING AFTER MYOCARDIAL-INFARCTION

Aims 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 pa tients with recent myocardial infarction were routinely submitted to d elayed (second week) catheterization. They also underwent systematic a ngioplasty of a significantly narrowed infarct-related artery with a s uitable anatomy, or reopening of a totally occluded infarct-related ar tery, and repeat follow-up catheterization after 4 months. Changes in left ventricular ejection fraction, left ventricular volumes, and perc ent of regional hypokinesia were assessed over the study period. Resul ts One hundred and thirty-two patients had two interpretable left vent riculograms and two interpretable coronary angiograms. At initial angi ography, 56 out of 96 patients with a patent infarct-related artery we re successfully submitted to percutaneous coronary angioplasty, of who m 25 had restenosis and eight had total reocclusion at follow-up angio graphy. Percutaneous transluminal coronary angioplasty was not attempt ed in the remaining 40 patients due to unsuitable anatomy in 18 or a n onsignificant lesion in 22. The infarct-related artery was totally occ luded 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 <40 ml.m(-2) (odds ratio=6.3, 95% con fidence interval=[2.5; 16.6]), initial end-systolic Volume index >50 m l.m(-2) (odds ratio=7.1, 95% confidence interval=[1.5; 25.8]), anterio r 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 signifi cantly narrowed infarct-related artery was not found predictive. Concl usions This study demonstrates that reocclusion of a previously open i nfarct-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. Thes e results emphasize the impact of long-term sustained patency of the i nfarct-related artery on the prevention of left ventricular dysfunctio n. The need for a larger randomized trial is recognised.