Kawasaki Disease(KD)patients with co-occurrent coronary artery aneurysms(CAAs)are prone to thrombosis.This study explores the thrombotic influence of morphology and hemodynamics in KD patients with CAAs.Patient-specif...Kawasaki Disease(KD)patients with co-occurrent coronary artery aneurysms(CAAs)are prone to thrombosis.This study explores the thrombotic influence of morphology and hemodynamics in KD patients with CAAs.Patient-specific computed tomography angiogram images of 9 patients were used to rebuild coronary models(including 23 aneurysms;10 in thrombosed group,and 13 in non-thrombosed group)and perform computational simulations to obtain the hemodynamic parameters.The thrombosed and non-thrombosed groups were compared in terms of six parameters,namely,the maximum diameter(D_(max)),aspect ratio(R_(l/d)),shape,time-averaged wall shear stress(TAWSS),oscillatory shear index(OSI),and relative residence time(RRT).The results showed that:(1)In thrombosed aneurysms,there were several vortex structures(eddy zone),of which the position changed continuously in a cardiac cycle.In non-thrombosed aneurysms,the streamlines showed a large streaming zone.(2)Abnormal hemodynamic areas of aneurysms with thrombosis tended to appear in the same region(especially the proximal and near myocardial side of aneurysms).(3)In the non-thrombosed group,there was a correlation between the morphological and hemodynamic parameters.In thrombosed aneurysms,the flow pulsatility has a significant impact on the flow pattern.The thrombosed coronary aneurysms exhibited more risk factors and the co-location of hemodynamic abnormalities was consistent with the position of thrombosis.A score of risk factors could provide the thrombotic information of coronary aneurysms,which might be helpful for long-term clinical management of KD patients.展开更多
AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 year...AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 years of age who required an abdominal computed tomography(CT) and central venous access. IVC cross-sectional areas were measured on CT scans at three levels, suprarenal(SR), juxtarenal(JR) and infrarenal(IR), during neutral breathing and again during the Valsalva maneuver. All patientswere instructed on how to perform a correct Valsalva maneuver. In order to reduce the total radiation dose in our patients, low-dose CT protocols were used in all patients. The venous blood pressure(systolic, diastolic and mean) was invasively measured at the same three levels with neutral breathing and the Valsalva maneuver during venous port implantation. From CT scans, threedimensional models of the IVC were constructed and a collapsibility index was calculated for each patient. These data were then correlated with venous pressures and cross-sectional areas.RESULTS: The mean patient age was 51.64 ± 12.01 years. The areas of the ellipse in neutral breathing were 394.49 ± 85.83(SR), 380.10 ± 74.55(JR), and 342.72 ± 49.77 mm2(IR), and 87.46 ± 18.35(SR), 92.64 ± 15.36(JR) and 70.05 ± 9.64 mm2(IR) during the Valsalva(P s < 0.001). There was a correlation between areas in neutral breathing and in the Valsalva maneuver(P < 0.05 in all areas). Large areas decreased more than smaller areas. The collapsibility indices were 0.49 ± 0.06(SR), 0.50 ± 0.04(JR) and 0.50 ± 0.04(IR), with no significant differences in any region. Reconstructed three-dimensional models showed a flattening of the IVC during Valsalva, adopting an ellipsoid cross-sectional shape. The mean pressures with neutral breathing were 9.44 ± 1.78(SR), 9.40 ± 1.44(JR) and 8.84 ± 1.03 mmHg(IR), and 81.08 ± 21.82(SR), 79.88 ± 19.01(JR) and 74.04 ± 16.56 mmHg(IR) during Valsalva(P s < 0.001). There was a negative correlation between cross-sectional caval area and venous blood pressure, but this was not statistically significant in any of the cases. There was a significant correlation between diastolic and mean pressures measured during neutral breathing and in Valsalva.CONCLUSION: Respiratory movements have a major influence on IVC dynamics. The increase in intracaval pressure during Valsalva results in a significant de-crease in the IVC cross-sectional area.展开更多
基金This work was supported by the National Natural Science Foundation of China[12072214]the Key Research&Development Project of Science and Technology of Sichuan Province[2021YFS0142]1⋅3⋅5 project for disciplines of excellence,West China Hospital,Sichuan University[ZYGD18013].
文摘Kawasaki Disease(KD)patients with co-occurrent coronary artery aneurysms(CAAs)are prone to thrombosis.This study explores the thrombotic influence of morphology and hemodynamics in KD patients with CAAs.Patient-specific computed tomography angiogram images of 9 patients were used to rebuild coronary models(including 23 aneurysms;10 in thrombosed group,and 13 in non-thrombosed group)and perform computational simulations to obtain the hemodynamic parameters.The thrombosed and non-thrombosed groups were compared in terms of six parameters,namely,the maximum diameter(D_(max)),aspect ratio(R_(l/d)),shape,time-averaged wall shear stress(TAWSS),oscillatory shear index(OSI),and relative residence time(RRT).The results showed that:(1)In thrombosed aneurysms,there were several vortex structures(eddy zone),of which the position changed continuously in a cardiac cycle.In non-thrombosed aneurysms,the streamlines showed a large streaming zone.(2)Abnormal hemodynamic areas of aneurysms with thrombosis tended to appear in the same region(especially the proximal and near myocardial side of aneurysms).(3)In the non-thrombosed group,there was a correlation between the morphological and hemodynamic parameters.In thrombosed aneurysms,the flow pulsatility has a significant impact on the flow pattern.The thrombosed coronary aneurysms exhibited more risk factors and the co-location of hemodynamic abnormalities was consistent with the position of thrombosis.A score of risk factors could provide the thrombotic information of coronary aneurysms,which might be helpful for long-term clinical management of KD patients.
文摘AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 years of age who required an abdominal computed tomography(CT) and central venous access. IVC cross-sectional areas were measured on CT scans at three levels, suprarenal(SR), juxtarenal(JR) and infrarenal(IR), during neutral breathing and again during the Valsalva maneuver. All patientswere instructed on how to perform a correct Valsalva maneuver. In order to reduce the total radiation dose in our patients, low-dose CT protocols were used in all patients. The venous blood pressure(systolic, diastolic and mean) was invasively measured at the same three levels with neutral breathing and the Valsalva maneuver during venous port implantation. From CT scans, threedimensional models of the IVC were constructed and a collapsibility index was calculated for each patient. These data were then correlated with venous pressures and cross-sectional areas.RESULTS: The mean patient age was 51.64 ± 12.01 years. The areas of the ellipse in neutral breathing were 394.49 ± 85.83(SR), 380.10 ± 74.55(JR), and 342.72 ± 49.77 mm2(IR), and 87.46 ± 18.35(SR), 92.64 ± 15.36(JR) and 70.05 ± 9.64 mm2(IR) during the Valsalva(P s < 0.001). There was a correlation between areas in neutral breathing and in the Valsalva maneuver(P < 0.05 in all areas). Large areas decreased more than smaller areas. The collapsibility indices were 0.49 ± 0.06(SR), 0.50 ± 0.04(JR) and 0.50 ± 0.04(IR), with no significant differences in any region. Reconstructed three-dimensional models showed a flattening of the IVC during Valsalva, adopting an ellipsoid cross-sectional shape. The mean pressures with neutral breathing were 9.44 ± 1.78(SR), 9.40 ± 1.44(JR) and 8.84 ± 1.03 mmHg(IR), and 81.08 ± 21.82(SR), 79.88 ± 19.01(JR) and 74.04 ± 16.56 mmHg(IR) during Valsalva(P s < 0.001). There was a negative correlation between cross-sectional caval area and venous blood pressure, but this was not statistically significant in any of the cases. There was a significant correlation between diastolic and mean pressures measured during neutral breathing and in Valsalva.CONCLUSION: Respiratory movements have a major influence on IVC dynamics. The increase in intracaval pressure during Valsalva results in a significant de-crease in the IVC cross-sectional area.
