Videodensitometric ejection fractions from intravenous digital subtraction left ventriculograms: correlation with conventional direct contrast and radionuclide ventriculography.

Abstract

Forty-three patients who had undergone direct-contrast ventriculography were submitted to intravenous digital subtraction ventriculography and first-pass radionuclide ventriculography to compare the left ventricular ejection fractions obtained by each method. Ejection fractions were calculated by the area-length method from the direct contrast ventriculograms, by both area-length and videodensitometric methods from the digital subtraction ventriculograms, and by count densitometry from the radionuclide ventriculograms. Satisfactory correlations were found between values obtained by the late mask resubtracted videodensitometric method and the radionuclide method (r = 0.85) and by the digital ventriculographic area length method and direct-contrast method (r = 0.88). Videodensitometric methods may be an alternative way to estimate left ventricular ejection fractions accurately without reliance on geometric assumptions about the shape of the left ventricular cavity.

Left ventricular dual-energy digital subtraction angiography: a motion immune digital subtraction technique

“…This comparison demonstrated that the dual-energy images were of sufficient quality to support quantitative analysis techniques. Two important quantitative techniques are densitometric analysis [7][8][9] and parametric imaging [17]. Both of these methodologies require some means of subtracting image structures unrelated to the signal of interest.…”

“…Contrast enhancement allows ventriculography to be performed with direct left ventricular injection of small amounts of contrast material [1][2][3] or with a venous injection [3][4][5][6]. Subtraction allows the determination of ejection fractions from high resolution images using an intravenous injection and videodensitometric techniques [7][8][9]. The potential for measuring absolute left ventricular volume exists [10].…”

Determination of cardiac ejection and valvular regurgitant fraction by on-line digital densitometry — methodology, validation, and application

“…(2) as (6) Because this expression is already a ratio of differences, slow background changes are less important.…”

“…(5) and (6) can be small, so that the results fluctuate from beat to beat. Some of these fluctuations may 115 be due to incomplete contrast mixing.…”

“…two parallel straight lines on a semi-logarithmic scale -through these four points and only inserting the fitted values D'~, D'~ ÷1, S'~, and S'i +1 in eqs. (5) and (6).…”