ECHOCONTRAST-VENTRICULOGRAPHY - DETERMINATION OF LEFT-VENTRICULAR FUNCTION PARAMETERS BY DIGITAL SUBTRACTION ECHOCARDIOGRAPHY

  • 1 November 1986
    • journal article
    • research article
    • Vol. 75  (11) , 650-658
Abstract
In 57 consecutive patients we examined whether digital substraction echocardiography (DSE) is able to determine left ventricular function parameters, in particular the ejection fraction (LV-EF). The most important step in DSE consists of the subtraction of digitized prey level information of the original echocardiogram from a phase-identical contrast image. In addition LV-EF, end-diastolic (EDV) and end-systolic volumes (ESV) were calculated by manual definition of endocardium in the original (Na) and contrast-echocardiograms (Ko). The results were then compared with the invasive cardiac catheterisation (Hk) data. We used 5.5% oxypolygelatine (Gelifundol S) as echo-contrast material and injected 2-4 ml as a bolus directly into the left ventricle. LV-EF calculated on the basis of automatic contour definition by DSE demonstrated a better correlation with cineangiographic data (r = 0.89, SEE 5.8% in 44 patients) than the manual input of endocardial borders in original echocardiograms (r = 0.71, SEE 8.1% in 47 patients). Good correlations were also found between EF-Ko and EF-Hk with r = 0.92 and an SEE of 4.3%; because there is a good agreement between EF-Ko and EF-DSE (r = 0.91, SEE 5.3%) these calculations closely approach the results of the invasive data. The EF-Na underestimates the EF-Hk markedly as a consequence of a systematic error: as compared to the contrast image the volumes of the original echocardiograms, in particular the ESV are overestimated and the ejection fraction as a derived parameter is calculated as too small. ESV-Hk versus ESV-Na: y = 0.82x + 24.4, ESV/Hk versus ESV-DSE: y = 0.88x + 37.0. In original echocardiograms the definition of the endocardium is unprecise and overestimates the true endocardium, in contrast-echocardiograms, however, the endocardium is a well-delineated, continuous contour arond the contrast-depot in the ventricular cavity. DSE uses this advantage of echo-contrast ventriculography; by means of automatic contour definition the determination of LV function parameters, particularly the LV-EF, are reproducible and independent of the echocardiographic image quality and the individual observer experience.