Echocardiography overestimates left ventricular mass in hemodialysis patients relative to magnetic resonance imaging

• Published in: Kidney international Vol. 56; no. 6; pp. 2248 - 2253
• Main Authors: Stewart, Graham A., Foster, John, Cowan, Michael, Rooney, Esther, Mcdonagh, Theresa, Dargie, Henry J., Rodger, R. Stuart C., Jardine, Alan G.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-12-1999; Nature Publishing
• Subjects: Adult; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Blood Pressure; cardiovascular disease; Cardiovascular system; Cohort Studies; Diagnostic Errors; dialysis; Echocardiography - standards; Echocardiography - statistics & numerical data; Emergency and intensive care: renal failure. Dialysis management; Female; Heart Ventricles - pathology; Humans; hypertension; Hypertension - complications; Hypertrophy, Left Ventricular - diagnostic imaging; Hypertrophy, Left Ventricular - etiology; Hypertrophy, Left Ventricular - pathology; Intensive care medicine; intravascular volume; Investigative techniques, diagnostic techniques (general aspects); Kidney Failure, Chronic - complications; left ventricular hypertrophy; Magnetic Resonance Imaging - standards; Magnetic Resonance Imaging - statistics & numerical data; Male; Medical sciences; Middle Aged; Observer Variation; Prognosis; Renal Dialysis; Ultrasonic investigative techniques; dialysis; cardiovascular disease; left ventricular hypertrophy; hypertension; intravascular volume; Sonography; Human; Hemodialysis; Cardiovascular disease; Nuclear magnetic resonance imaging; Left ventricle; Extrarenal dialysis; Measurement technique; Echography; Risk factor; Mass density; Diagnostic aid; Comparative study
• ISSN: 0085-2538; 1523-1755
• DOI: 10.1046/j.1523-1755.1999.00786.x

Echocardiography overestimates left ventricular mass in hemodialysis patients relative to magnetic resonance imaging.
Left ventricular hypertrophy (LVH) is a common finding and a strong adverse prognostic factor in patients with chronic renal failure. An accurate method of measuring left ventricular mass (LV mass) is therefore a prerequisite in the management of these patients. Recent evidence has suggested that echocardiography overestimates LV mass in patients with essential hypertension, and this error increases with increasing LV mass.
We studied 35 patients on maintenance hemodialysis within 24 hours of their last dialysis. LV mass was measured by both echocardiography and magnetic resonance imaging (MRI) performed less than three hours apart. Clinic and ambulatory blood pressure (ABPM), resting echocardiogram, and blood sampling were performed at the same visit.
Thirty-two patients had results from both methods. Clinic blood pressure, ABPM, and QT dispersion all correlated with LV mass, with a stronger correlation observed for MRI values. Intraobserver and interobserver variability were significantly greater for echocardiography (although similar to other published data). Comparing the two methods, the difference in LV mass values (echo minus magnetic resonance) increased in a linear fashion with an increasing mean mass and chamber diameter.
Echocardiography significantly overestimates LV mass relative to MRI in the presence of LVH and dilation. This overestimation is the result of assumptions made in the calculation of mass from echocardiography M-mode images, which are invalid when LV geometry is abnormal. This error is therefore amplified in dialysis patients, the majority of whom have LVH and in whom intravascular volume is constantly changing.