Measurement of left ventricular dimensions and function in patients with dilated cardiomyopathy.
Studies on medical therapy in heart failure are focused on changes of left ventricular (LV) dimensions and function. These changes may be small, requiring a large study group. We measured LV parameters (LV volumes, LV ejection fraction (LV-EF), and left ventricular mass (LVM)) with two-dimensional echocardiography (2D-echo) and magnetic resonance imaging (MRI) in 50 patients. Based on the difference between the measurements, we determined the variance of the results and calculated the sample sizes needed to detect changes of baseline values. For the calculated and measured parameters we found significant differences between the two techniques: LV-EF and LVM were higher in 2D-echo, and LV dimensions were comparable. The sample size to detect relevant changes from baseline with MRI was significantly (P < 0.01) smaller than in 2D-echo. We conclude that MRI is superior in clinical studies on left ventricular dimensional and functional changes, since measurements are more reproducible and the required sample size is substantially smaller, thereby reducing costs.
Charité, Universitätsklinikum. Medizinische Fakultät der Humboldt-Universität zu Berlin, Berlin, Germany. strohm@fvk-berlin.de
O
O
Strohm
J
J
Schulz-Menger
B
B
Pilz
K J
KJ
Osterziel
R
R
Dietz
M G
MG
Friedrich
D002306:Cardiac Volume / Q000187:drug effects / Q000502:physiology*; D002311:Cardiomyopathy, Dilated / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D004311:Double-Blind Method; D004452:Echocardiography; D005080:Exercise Test; D013006:Growth Hormone / Q000009:adverse effects / Q000627:therapeutic use; D006333:Heart Failure / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D009206:Myocardium / Q000473:pathology; D011237:Predictive Value of Tests; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology*
D013006:Growth Hormone