LATE POTENTIALS DURING LEFT-VENTRICULAR HEALING OF ACUTE MYOCARDIAL-INFARCTION

Background: Late potentials and left ventricular remodeling are import ant factors in the prognosis of acute myocardial infarction. However, the relationship between late potentials and ventricular remodeling ha s not been fully evaluated. Methods: We evaluated clinical characteris tics, coronary angiographic findings and radionuclide angiographic mea sures about 1 month after an acute myocardial infarction in patients w ith and without late potentials. Results: Although the left ventricula r ejection fraction of patients with late potentials was not different from that of patients without late potentials, the left ventricular e nd-diastolic volume of patients with late potentials was larger than t hat of patients without late potentials (P < 0.05). There was a signif icant positive correlation between the left ventricular end-diastolic volume and the filtered QRS duration (r = 0.53, P < 0.001). The root m ean square of the voltage in the terminal 40 ms and the low-amplitude signal duration of < 40 mu V in the terminal QRS sequence were also co rrelated with the left ventricular end-diastolic volume (r = 0.40, P < 0.02, and r = 0.39, P < 0.02, respectively). Patency of the infarct-r elated vessel in the late phase of an acute myocardial infarction was an important factor associated with the occurrence of late potentials (P < 0.01). Conclusion: A larger left ventricular end-diastolic volume in patients with late potentials might be associated with left ventri cular remodeling during the first month after an acute myocardial infa rction.