Exploratory Development Of Full-volume Three-dimensional Echocardiography And Transesophageal Echocardiography In Patients With Tetralogy Of Fallot

Full-volume three-dimensional echocardiography(FV3DE) is one of the recent new developments in the arena of echohcardiography.There are basically two methods of displaying FV3DE datasets,namely volume-rendered view and two-dimensional cross-sectional view from any desired cut-planes.It makes the cardiovascular observation from any orientation and any angle possible.Any images can be generated from FV3DE as desired,some of which are physically unobtainable by conventional two-dimensional echocardiography(2DE) with either transthoracic or tranesophageal acoustic windows.Quantitative analysis of FV3DE is also accessible. Measurements of length or area can be done in the cross-sectional view,while achievements of volume,volume-derived function or volume-derived synchronicity curves are realized in the volume-rendered view with matched analytical software.To make the best use of FV3DE,the study of morphologic or quantitative analysis and its clinical application in heart disease should be carried out.Transesophageal echocardiography(TEE) is the imaging diagnostic technique scanning cardiovascular structure from the rear or bottom of the heart by the probe within esophagus or stomach.TEE provides a novel scanning way,especially in the cases with imperfect acoustic window of transthoracic echocardiography(TTE), remote from costal bone and air-borne pulmonary tissue.TEE plays an important role, such as preoperative diagnosing,perioperative monitoring or postoperative evaluating, in cardiovascular disease.It has already become one of the significant imaging tools in the field of pediatric cardiology.While,regretfully,there is few reports about pediatric cases with large sample.The potential clinical value and its dormant limitations are still to be discovered.Given these together,our study aimed to discuss the image-analytical methodology of FV3DE and TEE,focusing our attention on the applicable value of these new technologies in pediatric patients with tetralogy of Fallot(TOF). Partâ… The Application of Full-volume Three-dimensional Echocardiography in Patients with Tetralogy of FallotObjectiveTo establish the methodology for diagnosis of congenital heart disease(CHD) with FV3DE,to test the feasibility of the examination protocol of FV3DE in cases with tetralogy of Fallot(TOF),one of representatives of complex CHD,and to test the reliability of quantifying TOF with FV3DE.MethodsThe images were post-processed with online or offline QLAB workstation after the FV3DE datasets acquired."Autocrop" and "Plane Adj" functional keys were used to display the volumetric view for the region of interest(ROI) from any angle when the FV3DE datasets were cropped orthogonally or arbitrarily.In the multiplanar reconstruction(MPR) window,ROI in cross-sectional view was obtained by moving the orthogonal axis or oblique axis.Based on Van Praagh sequential segmental approach,following the above rule,TOF was diagnosed morphologically and quantitatively by post-processing software.Results1.Establishing the examination protocol for FV3DE.The volumetric views and sectional views from FV3DE dataset were displayed by consecutive orthogonal cropping,including coronal,saggital and horizontal directions.The views of ROI at non-orthogonal planes were also displayed by appropriate cropping.In addition,the typical volumetric views of cardiovascular structure were nominated.2.TOF was diagnosed with volumetric views by consecutive orthogonal cropping and typical volumetric views of main malformations from FV3DE datasets.Compared with surgical findings,the accordance rate of FV3DE in diagnosing TOF was 100%. The accordance rate was 100%and 97.2%in determining the positions of ventricular septal defect(VSD) and right ventricular outflow tract obstruction(RVOTO), respectively,both of which were higher than 2DE.However,the detectable rate for co-existed extracardiac anomalies and minute structures was lower than 2DE plus color Doppler imaging.3.It provided a novel approach to quantify TOF with cross-sectional view extracted from FV3DE datasets.No significant difference was observed between FV3DE and surgical observation in measuring VSD.While,conventional 2DE underestimated the size of VSD.Smaller anterior-posterior diameter was revealed as compared with lateral diameter by FV3DE,suggesting the morphology of infundibulum of TOF was not circular shape.No significant difference was observed between FV3DE,2DE and surgical observation in measuring the diameter of pulmonary valvular annulus,but FV3DE was better correlated with surgical observation than 2DE(r=0.899 vs. r=0.839).No significant difference was observed between FV3DE,2DE and angiography in measuring LPA or RPA.The correlation coeffients between FV3DE and angiography were higher than those between 2DE and angiography(LPA: r=0.947 vs.r=0.797 and RPA:r=0.987 vs.r=0.831).The sectional area of RVOT could be measured by FV3DE.The pulmonary diameter index(PDI) and the pulmonary area index(PAI) derived from FV3DE were well correlated with McGoon index and Nakata index derived from angiography(r=0.877 and r=0.983, respectively).Compared with healthy control group,the TOF group had decresed LVEF and RVEF;Smaller LA.Vmax,larger RA.Vmax and RA.Vp,decreased LA.Vpe,LA.Vpef and LA.Vte,increased LA.Vaef,RA.Vae,RA.Vaef,RA.Vte and RA.Vtef.ConclusionsThe study provided the new method to dignose CHD with the volumetric views from FV3DE dataset by cropping orthogonally or arbitrarily.It provided the new planes to measure the diameter or area of cardiovascular structure with the appropriate sectional views from FV3DE dataset.Cardiac volume could also be measured by FV3DE without geometrical hypothesis.It suggested that the volumetric view and cross-sectional view from FV3DE datasets made great innovations at the morphologic or quantitative diagnosis in children with TOF.Partâ…¡The Application of Transesophageal Echocardiography in Patients with Tetralogy of FallotObjectiveTo establish the methodology of perioperative TEE in children with CHD,and to test the feasibility of the examination protocol for perioperative TEE in patients with TOF. MethodsPediatric biplane or multiplane TEE was used.Before bypass was initiated,the preoperative TEE diagnoses were made.TEE was performed again to evaluate the instant result of the operation after the spontaneous beat of the heart was resumed. During bypass,the probe was frozen staying in stomach.The study of perioperative TEE was carried out in 105 cases of TOF to elucidate its application value during perioperative period.Results1.Establishing the examination protocol for perioperative TEE.The sectional views of TEE for diagnosing pediatric CHD were selected.The appropriate sectional views of TEE to display given cardiovascular structure were also provided.The value of above protocol was validated by 977 cases with CHD,among which,TEE made corrections or supplements for TTE in 68 cases(7.0%),including septal defects(atrial septal defects,especially),valvular malformations and abnormal muscular bundles in ventricle.Compared with TTE,TEE had limitations in 10 cases(1.0%),including patent ductus arteriosus,coarctation of aorta,and anomalous pulmonary venous connection.2.Compared with surgical findings,the accordance rate of TEE in diagnosing TOF was 100%.The accordance rate was 99.0%and 98.1%in determining the positions of VSD and RVOTO,respectively,both of which were higher than TTE.In addition,the detectable rate for co-existed anomalies by TEE was also higher than that by TTE.3.Postoperative TEE showed that residual shunt rate was 30.8%,residual obstruction rate was 17.3%and pulmonary regurgitation rate was 67.3%,respectively,.Residual RVOTO was not correlated with transannular patch(TAP),but the patients underwent TAP were more apt to pulmonary regurgitation(PR) than those only with enlargement patch.Preservation of pulmonary valve could not decrease the degree of PR. Reconstruction of RVOT with Contegra could reduce the occurrence of PR.ConclusionsThe examination protocol for perioperative TEE had great impact on diagnosing TOF before operation and detecting residual problems after operation,which might influence the treatment strategy and improve the quality of surgical procedures.The value of perioperative TEE was validated in children with TOF.Preoperative TEE provided suffiecnt information for surgical plan,while postoperative TEE could evaluate the surgical results instantly.The impacts of different surgical method on residual problems of RVOT were also detected by TEE.