ECHOCARDIOGRAPHY OVERESTIMATES LEFT-VENTRICULAR MASS - A COMPARATIVE-STUDY WITH MAGNETIC-RESONANCE-IMAGING IN PATIENTS WITH HYPERTENSION

Objective To compare measurement of left ventricular mass (LVM) by M-m ode echocardiography and magnetic resonance imaging (MRI) in hypertens ive subjects. Design A prospective study. Subjects Twenty-four untreat ed hypertensive patients [19 men and five women, aged 51 +/- 2 (mean /- SEM) years, supine blood pressure 159/101 +/- 3/1 mmHg]. Setting Th e Blood Pressure Unit, St Georges Hospital Medical School and Magnetic Resonance Unit, Royal Brompton National Heart and Lung Hospital, Lond on. Main outcome measures LVM estimated both by M-mode echocardiograph y and by MRI. Results Using three standard M-mode formulae, widely dif ferent values of LVM were obtained with echocardiography [American Soc iety of Echocardiography (ASE) 319 +/- 21 g, Penn 273 +/- 19 g, Teichh olz 191 +/- 11 g]. By MRI, the LVM was 232 +/- 11 g. The differences b etween MRI and echocardiography could not be explained in terms of the timing of measurements in the cardiac cycle. When single-slice MRI me asurements at the appropriate level were applied to the ASE and Penn f ormulae, the LVM was again overestimated. Conclusion Our study has sho wn major differences in LVM estimated using methods based on one-dimen sional (echocardiography) compared with three-dimensional (MRI) data. These differences seem to be largely the result of the geometrical ass umptions on which M-mode measurements are based. Our findings have imp ortant clinical implications for the assessment of the severity and re sponse to treatment of left ventricular hypertrophy in hypertensive pa tients.