[The reliability of angiographic volume determination of the left ventricle using digital image subtraction--significance in stress tests].
Using the technique of digital subtraction angiography (DSA), left ventricular volumes can be determined after intravenous injection of contrast medium at rest and during exercise. The significance of the well known errors of angiographic determination of left ventricular volumes was investigated in 22 patients before and during a bicycle exercise test. Before and after exercise 40 ml of contrast medium were injected (18 ml/s) intravenously to calculate left ventricular volumes. Enddiastolic and endsystolic contours of the left ventricle were traced by two investigators (A and B) on five different days. Using these contours, volumes were calculated by a computer system. The first calculation of both investigators (single measurement) and the mean value of all five calculations (repetitive measurements) were compared. In the same procedure left ventricular contours of six patients were calculated after conventional contrast ventriculography (40 ml of contrast medium). No systematic deviations were found in comparing the results of both investigators using the single or repetitive method by means of DSA: (VolB = 0.86 VolA + 12.2, r = 0.97 versus VolB = 0.96 VolA + 9.1, r = 0.99). Compared to single method the residuals (Syx) of the repetitive method were significantly smaller: Syx = +/- 16.3 ml vs +/- 8.9 ml (p less than 0.01). Similar results were found in conventional ventriculography: single method Syx = +/- 18.7 ml and repetitive method Syx = +/- 8.8 ml (p less than 0.01). Comparing the volumes determined by DSA and by conventional ventriculography, respectively, no significant differences were found.(ABSTRACT TRUNCATED AT 250 WORDS)
Jehle
J
J
Medizinische Klinik, Universität Düsseldorf.
Block
M
M
Schmiel
F K
FK
Schwammenthal
E
E
Spiller
P
P
Uhlmann
D
D
Ulbricht
L
L
D000792:Angiography; D002302:Cardiac Output; D002306:Cardiac Volume; D003971:Diastole; D005080:Exercise Test; D006331:Heart Diseases / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D011857:Radiographic Image Interpretation, Computer-Assisted; D013382:Subtraction Technique; D013599:Systole
Zuverlässigkeit angiographischer Volumenbestimmung des linken Ventrikels mittels digitaler Bildsubtraktion--Bedeutung bei Belastungsuntersuchungen.