[Time-course changes in serum myosin light chain 1 concentration and clinical implication in patients with reperfused...

The correlation between the time-course changes in the serum concentration of myosin light chain 1 (ML-1) and left ventricular (LV) function was investigated in 37 patients with initial anterior acute myocardial infarction (AMI) after successful reperfusion. All patients were confirmed to have coronary arteries recanalized to TIMI grade 3 within 6 hours of AMI and patent arteries about 2 weeks after recanalization. LV function was assessed by left ventriculography. The patients were divided into two groups according to the time-course changes in the serum concentration of ML-1; 20 who showed an early peak of the serum ML-1 level within 24 hours and a late peak 3 to 5 days after recanalization (bimodal pattern: group B), and 17 who showed a single peak of the serum ML-1 level after recanalization (unimodal pattern: group U). The sum of ST elevation in an electrocardiogram before reperfusion and the additional ST elevation during reperfusion were both greater in group B than in group U (p < 0.1 and p < 0.05, respectively). The peak serum concentration of creatine kinase was significantly greater in group B than group U. LV dilatation was more extensive and the improvement of LV function was poorer in group B compared to group U.(ABSTRACT TRUNCATED AT 250 WORDS)