The Application Of MSCT In Heart Structure And Function Evaluation

Part1The accuracy study between echocardiography and256iCT in quantitative measurement left atrial volumeObjective:To determine the accuracy of256iCT in quantifying the left atrial (LA) volume.Methods:①Four atificial phantoms were created and underwent256iCT and echocardiography on the same day. The measurement results were compared with those of256iCT automatic method,256iCT semi-automatic method, echocardiography and real volume.②Sixty patients received256iCT coronary CTA and echocardiography in12hours for measuring left atrial volume. Sixty patients were separated into two groups by gender, then analysis the difference between256iCT automatic method and echocardiography in the overall sample group,the male group and the group of female.Result:①In the phantom experiment, there showed no difference between256iCT automatic method and real volume (P>0.05), while there were significant differences between256iCT semi-automatic method or echocardiography and real volume (P<0.05).②There was significance difference between256iCT automatic method and echocardiography in the overall sample group (P<0.05). The mean LA volume using echocardiography was lower about24%than that obtained with256iCT automatic method. The analysis results of different gender group was same as the overall sample group.Conclusion:256iCT can be used in the left atrium volume quantitative measurement, the result is objective and accurate and repeatable, which has the important clinical value. Part2Quantitative Study of Left Ventricular Anatomic Structure and Function by256iCTObjective:To assess reference values for the normal left ventricle construction and function with256iCT, and confirm the relationships between those indicators and age and sex.Methods:Collection506patients underwent256iCT coronary artery CTA and their examination were normal.Reconstructing the image data and confirm left ventricular end-systole and end-diastole frames.The following indicators were obtained:septal wall thickness (SWT), posterior wall thickness(PWT), left ventricular inner diameter(LVID), end-diastolic volume(EDV), end-systolic volume(ESV), stroke volume(SV), ejection fraction(EF).Then analyze them by statistics.Result:The95%reference ranges of SWT、PWT、LVID in left ventricular end-diastole is4.4～12.1mm,4.0～14.0mm,28.1-60.8mm, respectively,while6.2～15.7mm,7.9～20.8mm,18.1～46.3mm in left ventricular end-systole. The95%reference range of EDV, ESV, SV, EF is55.9～165.7ml,20.9～75.9ml,25.8～98.6ml,39.8%～78.3%, respectively. There was significant difference among age groups in LVID (P<0.05), which in left ventricular end-diastole or end-systole had the tendency of increase. SWT, AWT in left ventricular end-diastole or end-systole and EF had the tendency of increase, while decrease those of EDV、ESV、SV, but all of the above parameters have no significant difference among age groups (P<0.05). Except of EF, there were significant difference between males and females in all parameters (P<0.05), and the male group are larger than those of the female group.Conclusion:This study primarily established normal reference parameters of the left atrial structure and function, and provide meaningful informations for clinical diagnosis, risk rating and prognosis. Part3The Application of256iCT in Quantitative Studying Left Atrial Related ParametersObjective:To assess reference values for the normal left atrial construction and function by256iCT.Methods:Retrospectively selected506patients who underwent256iCT coronary artery CTA and their physical examination were normal. All individuals had no history of cardiac disease in the past six months. Confirming left ventricular end-systole and end-diastole, the following values were obtained:left atrial maximal volume (LAVmax), left atrial minimal volume(LAVmin), left atrial maximal anterior posterior diameter(LADmax), left atrial minimal anterior posterior diameter (LADmin), left atrial wall thickness (LAT), then left atrial volume index (LAVI) and left atrial ejection fraction (LAEF) was calculated.Results:The95%medical reference ranges of LAVmax, LAVmin, LADmax, LADmin, LAT, LAVI and LAEF are15.9～82.7ml,10.0-51.3ml,25.8～50.8mm,21.0～45.2mm,1.1～3.1mm,18.9～39.3ml/m2,24.7%～51.9%, respectively. LAVmax, LAVmin and LADmin showed significant difference among age groups (P<0.05), the values of people over the age of40year larger than that of age under40.Significant difference were found for LAVmax, LAVmin between males and females (P<0.05), the values of males greater than that of females, whereas no significant differences were found for the other parameters between males and females (P>0.05). LAVmax and LAVmin showed significant age differences, and with age, the values had the tendency of increase age (P<0.05).LAVI and LAEF showed no significant difference between either males and females or different age groups. Conclusion:This study primarily established normal medical reference values of the related parameters of the left atrial, and provide the reference standard for clinical assessment of left atrial anatomical structure and function.