title: Assessment of ejection fraction of the right and left ventricles in patients with acute myocardial infarction by magnetic resonance imaging.
abstract: Right and left ventricular function in acute myocardial infarction (AMI) was assessed by ECG-gated magnetic resonance imagine (MRI) in 64 patients and 8 volunteers. Five short axis images for intrinsic cardiac long-axis of the left ventricle were obtained at 9 msec and 309 msec after the R wave as end-diastole and end-systole. Right and left ventricular volumes were measured by Simpson's rule. The intraobserver variabilities in right and left ventricular ejection fraction (RVEF: r = 0.94, LVEF: 0.89) were excellent. The interobserver variabilities in RVEF (r = 0.61) and LVEF (r = 0.77) were fair. LVEF, but not RVEF, was significantly reduced in patients with AMI. Among left ventricular dysfunction (LVEF < or = 40%) patients, 50% exhibited right ventricular dysfunction (RVEF < or = 40%). Among patients without left ventricular dysfunction, only 12% exhibited right ventricular dysfunction. In left ventricular and biventricular dysfunction compared with control, the left ventricular end-diastolic volume index increased (65 +/- 10 ml/m2, 68 +/- 12 ml/m2 vs 54 +/- 8 ml/m2), the end-systolic volume index increased (40 +/- 16 ml/m2, 43 +/- 7 ml/m2 vs 18 +/- 1 ml/m2), and the right ventricular end-diastolic volume index decreased (52 +/- 13 ml/m2, 53 +/- 20 ml/m2 vs 65 +/- 8 ml/m2). MRI can thus be used to assess ventricular systolic function. Since patients with left ventricular dysfunction revealed a high incidence of right ventricular dysfunction, an interaction between the left and right ventricles may occur in ventricular dysfunction.
authors.affiliation: Second Department of Internal Medicines, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: K
authors.initials: K
authors.lastname: Imai
authors.forename: Y
authors.initials: Y
authors.lastname: Araki
authors.forename: Y
authors.initials: Y
authors.lastname: Nishino
authors.forename: S
authors.initials: S
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Ozawa
authors.forename: T
authors.initials: T
authors.lastname: Yasugi
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000503:physiopathology*; D015203:Reproducibility of Results; D013318:Stroke Volume / Q000502:physiology*