Cine MR imaging after myocardial infarction - Assessment and follow-up of regional and global left ventricular function

Myocardial infarction often leads to regional wall motion defects and in ca se of large defects to remodeling of the left ventricle. With this study, c hanges in regional and global myocardial function of 12 patients 3 weeks af ter myocardial infarction and after revascularization therapy were determin ed using MRI. Cine MRI was performed at study entry at rest and during low- dose dobutamine stimulation. All patients were re-examined at rest 3 and 6 months after the revascularization, including analysis of wall thickening a nd of left ventricular end-diastolic volume index (LVEDVI), end-systolic vo lume index (LVESVI), ejection fraction (LVEF), and mass index. After revasc ularization, 6 patients with stress-induced improvement of regional wall th ickening recovered, 4 patients without improvement did not, but 2 patients without stress-induced improvement of wall thickening also recovered. Conce rning global cardiac function, patients with mainly improved regional wall motion also showed a lower LVESVI and a higher LVEF than patients without i mprovement of regional contractility 6 months after revascularization in co mparison to study entry. In conclusion, improvement of global myocardial fu nction after revascularization is higher in patients with improved contract ility in the infarcted region. The extent of the response of regions with w all motion defects to dobutamine stress correlates with the actual improvem ent after revascularization, and, therefore, dobutamine stress MRI may be h elpful in selecting patients that will have a higher benefit from a revascu larization therapy.