LONG-TERM FUNCTION IN THE REMOTE REGION AFTER MYOCARDIAL-INFARCTION -IMPORTANCE OF SIGNIFICANT CORONARY STENOSES IN THE NON-INFARCT-RELATED ARTERY

Background-Left ventricular (LV) function is the most important determ inant of outcome after a myocardial infarction. Global LV function aft er a myocardial infarction is affected not only by wall motion in the infarct zone but also by regional function in the contralateral territ ory. It was, hypothesised that the presence of significant stenoses in coronary arteries supplying the contralateral territory might influen ce the ability of this region to compensate for damaged myocardium aft er a myocardial infarction. Methods and results-79 patients treated wi th thrombolysis for acute myocardial infarction had coronary and ventr icular angiograms within 24 h and at a mean follow up of 12 months aft er myocardial infarction. Wall motion in the contralateral territory w as analysed and scored by the centre line method and the change over t ime was correlated with the presence or absence of significant (>70%) diameter stenoses in the non-infarct-related artery. Mean (SD) contral ateral territory motion worsened, from 0.74 (1.78) to -1.55 (2.06) SD chord (p < 0.001) in 40 patients with stenoses, whereas contralateral territory motion improved from -0.02 (2.4) to 0.63 (2.21) SD chord (p < 0.05) in the 39 patients without coronary stenoses. The same pattern was present whether or not the infarct artery was patent. The global left ventricular ejection fraction at 12 months was also related to co ntralateral territory motion (r = 0.71, p < 0.001) and to the presence of coronary stenoses (54 (15)% in those with coronary stenoses and 62 (16)% in those without, p < 0.05). Conclusion-The results demonstrate that significant stenoses in arteries supplying the non-infarct terri tory adversely affect global and regional left ventricular function af ter a transmural infarction. Non-infarct artery anatomy should be cons idered in intervention strategies to improve left ventricular function after acute myocardial infarction.