Subject(s)
Blood Donors , Mass Screening/methods , Nucleic Acid Amplification Techniques/methods , Virus Diseases/diagnosis , HIV-1/genetics , Hepacivirus/genetics , Humans , International Cooperation , Mass Screening/standards , Mass Screening/trends , Nucleic Acid Amplification Techniques/statistics & numerical data , RNA, Viral/blood , Sensitivity and Specificity , Transfusion Reaction , Virus Diseases/transmissionABSTRACT
Two-dimensional echocardiography underestimates left ventricular volume compared with cineventriculography. To exclude the influence of difference in heart rate, blood pressure, respiration phases and any effect of the contrast material on left ventricular function, simultaneous studies of two-dimensional echocardiography and cineventriculography-echoventriculography were performed in 46 patients. Apical two-dimensional echocardiograms in the right anterior oblique (RAO) equivalent view were recorded before and during cineventriculography in the 30 degrees RAO projection. End-diastolic and end-systolic volumes (EDV and ESV) were calculated using a disc method with a semiautomatic computer system. The echo transducer position relative to the left ventricular apex and long axis was analyzed. For EDV determined by two-dimensional echocardiography and cineventriculography, the linear regression equation was y = 0.659x + 0.8, SEE = +/- 26.2 ml, r = 0.907. For ESV, the regression equation was y = 0.571x + 17.8, r = 0.938, SEE = +/- 18.6 ml, and for ejection fraction (EF) it was y = 0.606x + 13.0, r = 0.803, SEE = +/- 9.1%. Injection of contrast material resulted in only a small increase of stroke volume, caused by an increase of EDV as analyzed by echoventriculography. In all but two patients, the transducer position was found to be anterior and superior to the left ventricular anatomic apex, as evaluated by filming the echo transducer position during cineventriculography in 46 patients in the 30 degrees RAO projection and in 15 patients consecutively in the 60 degrees left anterior oblique and 30-40 degrees cranial projections. Thus, tangential cuts of the ventricle resulted in underestimation of diameters, long axis and ventricular volumes. These methodologic problems are exacerbated by slice-thickness artifacts. Furthermore, different outlining of left ventricular contour -- outer border of ventricular trabeculae for cine ventriculography and inner border for two-dimensional echocardiography -- seemed to result in underestimation of volume by echocardiography.
Subject(s)
Cineradiography/methods , Coronary Disease/diagnosis , Echocardiography/methods , Adult , Cardiac Volume , Computers , Female , Heart Ventricles , Humans , Male , Middle Aged , Myocardial Contraction , Stroke VolumeABSTRACT
A difference was obtained between cineventriculography and 2-D echocardiography in the determination of left ventricular volume and ejection fraction. Normal values obtained by the former could not be used for the latter. The authors, therefore, determined their own normal values. Apical 2-D echocardiography was used for the normal group (35 males, mean age 30.2 years; 20 females, mean age 26.2 years). In addition to mean values and standard deviations, one-sided tolerance limits (T) were calculated, separating the normal range from abnormal within 95% confidence limits for 90% of the total group. End-diastolic and end-systolic volume index in males was 66.8 +/- 8.8 ml/m2 compared with 26.9 +/- 5.2 ml/m2 on biplane evaluation. Tolerance limits were calculated at 82.0 and 35.9 ml/m2, respectively. Stroke volume index was 39.9 +/- 7.0 ml/m2, T = 27.8 ml/m2, ejection fraction 59.2 +/- 6.0%, T = 48.8%. End-diastolic and -systolic volume index for females had a mean of 60.7 +/- 12.5 ml/m2, T = 85.0 ml/m2, and 25.7 +/- 7.4 ml/m2, T = 40.1 ml/m2, respectively. Stroke volume index was 56.5 +/- 10.6 ml/m2, T = 35.9 ml/m2, the ejection fraction 58.1 +/- 6.5%, T = 45.5%. Between monoplane and biplane measurements of apical 2-D echocardiograms there was no significant difference. Normal values for volume and ejection fraction of the left ventricle, determined from apical four-chamber and RAO-equivalent cuts make it possible to categorize the function of the heart and to provide the basis for further studies of the sensitivity and specificity of the method.
Subject(s)
Echocardiography/methods , Adolescent , Adult , Cardiac Volume , Female , Heart Ventricles , Humans , Male , Mathematics , Reference Values , Sex FactorsABSTRACT
The irregularity and complexity of the right ventricle is the reason why no accurate method for right ventricular volume determination exists. A new method for right ventricular volume determination particularly for two-dimensional echocardiography was developed-it is called subtraction method-and was compared with the pyramid and Simpson's methods. The partial volume of the left ventricle and septum was subtracted from total volume of right and left ventricle including interventricular septum. Thus right ventricular volume resulted. Total and partial volume were computer-assisted calculated by use of biplane methods, preferably Simpson's rule. The method was proved with thinwall silicon-rubber model hearts of the left and right ventricle. Two orthogonal planes in the long-axis were filmed by radiography or scanned in a water bath by two-dimensional echocardiography equivalent to RAO and LAO-projections of cineangiocardiograms or to four- and two-chamber views of apical two-dimensional echocardiograms. For calculation of the major axes of the elliptical sections, summed up by Simpson's rule, they were derived from the LAO-projection and the four-chamber view, respectively, the minor axis approximated from the RAO-projection and the two-chamber view. For comparison of direct-measured volume and two-dimensional echocardiographically determined volume, regression equation was given by y = 1.01 x -3.2, correlation-coefficient, r = 0.977, and standard error of estimate (SEE) +/- 10.5 ml. For radiography, regression equation was y = 0.909 x + 13.3,r = 0.983, SEE = +/- 8.0 ml. For pyramid method and Simpson's rule, higher standard errors and lower correlation coefficients were found. Between radiography and two-dimensional echocardiography a mean difference of 4.3 +/- 13.2 ml, using subtraction method, and -10.2 +/- 22.9 ml, using pyramid method, as well as -0,6 +/- 18.5 ml, using Simpson's rule, were calculated for right ventricular volume measurements. Differences were not significant. The subtraction method seems to be useful for calculation of right ventricular volume by radiography as well as two-dimensional echocardiography. Further studies in isolated hearts and patients are necessary for final judgment of the accuracy of this new method.
