Application Of Echocardiography In Minimally Invasive Closure Of Ventricular Septal Defect And Postoperative Evaluation

Part Ⅰ The value of transesophageal echocardiography for minimally invasive closure of ventricular septal defect and postoperative follow-upPurpose:To explore the application value of transthoracic echocardiography(TTE)and transesophageal echocardiography(TEE)in minimally invasive closure of ventricular septal defect(VSD).Echocardiography is mainly used for preoperative cases selection,intraoperative occluders selection,monitoring and guiding placement of occluders and postoperative follow-up.Methods:A total of 162 patients who underwent minimally invasive closure of VSD under the guidance of 2-dimensional(2D)and 3-dimensional TEE(3D-TEE)in the cardiac surgery department of our hospital from February 2016 to August 2019 were selected.The inclusion criteria were complete preoperative examination,routine follow-up after closure of VSD.Preoperative thoracic echocardiography(TTE)was used to evaluate the size and type of ventricular septal defect and its relationship with adjacent tissues,and to select patients suitable for minimally invasive surgery,excluding patients with large VSD complicated with pulmonary hypertension or patients with other complex malformations,patients with aortic valve prolapse and patients with obvious tricuspid regurgitation.For patients with membranous and perimembranous VSD,a small incision on the right side of the sternum was used for the peratrial approach;for patients with intracristal type,subarterial type,a small incision on the left side of the sternum was used for the per-ventricular approach.Patients weighing less than 15kg used a transesophageal probe designed for children;Patients weighing more than 15kg used 3D transesophageal probe,intraoperative real time 3D-TEE was used to reevaluate the size of VSD position and to determine the type of occluder.Generally,the size of occluder was maximum diameter of the defect+2mm,wide-edge occluder could be used for multioutlet type of PmVSD with membrane tumor,and eccentric occluder could be used for VSD with tiny margin(<1mm)under the aotic valve such as subarterial and some intracristal VSD.Two-dimensional and RT-3D-TEE were used to guide the placement process of the occluder during which the catheter was guided to avoid the important structures such as the tricuspid valve and chordae tendontosis,to prevent the injury of the valve and other important structures.After the completion of the occlusion,we used TEE to check the stability of the occluder,and whether there were complications such as residual shunt or new valve regurgitation.The follow-up was carried out by TTE at outpatients,pericardial effusion,arrhythmia,valve regurgitation,device displacement and other complications were recorded to evaluate the safety of surgery.All data were analyzed by SPSS 25.0 statistical software.Continuous variables were expressed by mean ± standard deviation,and classified data were expressed by case number or percentage.T-test was used to compare continuous variables between two groups,and Pearson correlation analysis was used for the relationship between two variables,P<0.05 was considered statistically significant.Results:Among 162 patients with VSD,156 cases were successfully occluded with a success rate of 96.29%,including 136 cases of perimembrane VSD,20 cases of intracristal VSD and 6 cases of subarterial VSD.The mean age was 5.6±3.4 years(range 1 to 14 years)and the body weight was 17.1±5.2kg(range8.01 to 49.12kg).The success rate was related to VSD classification,and the success rate of perimembranous and intracristal VSD was 97.05%and 100%,respectively.There were fewer cases of subarterial type and the success rate was relatively low(66.67%),which was related to the tiny margin of the VSD to aortic valves.One patient with patent foramen ovale underwent closure at the same time.There were 6 patients,including 2 cases of subarterial type and 4 cases of multioutlet PmVSD,who were not successfully occluded due to large residual shunt or valve regurgitation,and they were surgically repaired with the aid of cardiopulmonary bypass.The mean value of VSD measured by TTE before occlusion was 0.36±0.15cm,ranging from 0.20 tol.15cm;the mean value of VSD measured by TEE during the surgery was 0.39±0.16cm,ranging from 0.21 to 1.03cm;all the value was the VSD size at occlusion position.The mean value of occluder was 6.1± 1.9mm,ranging from 4 to 14 mm,the size of the occluder is the waist size.The statistical results showed that the VSD size measured by intraoperative TEE had a better correlation with occluder size than TTE at outpatients(TEE r=0.96,TTE r=0.91,P<0.05).The left atrial and left ventricle diameter were significantly reduced at 1 week and 1 month after the occlusion,compared with that before occlusion(P<0.05),and the cardiac function was within the normal range with no significant difference.Routine follow-up showed that the occluders were fixed in all cases,and 7 cases with residual shunt,including 2 cases with eccentric occluders and 5 cases with symmetrical occluders.The residual shunt disappeared in 3 cases at 3 months after surgery,and no residual shunt reappeared.The residual shunt still existed in 1 case at 24 months after occlusion,with no significant haemodynamic influence.There were 13 cases with pericardial effusion,which disappeared after diuretic treatment.Pericardial puncture drainage was performed in 1 case with midium amount of pericardial effusion.7 patients showed incomplete right bundle branch block.there was no severe atrioventricular block,device displacement or other serious complication occurred.Conclusion:2D and 3D echocardiography plays a reliable and important role in the selection of preoperative cases,intraoperative monitoring and guidance,and the postoperative follow up.The correlation between VSD size measured by intraoperative TEE and occluder size was better than TTE.The follow-up data suggest that minimally invasive closure of VSD was safe.Part Ⅱ Comparative study between mimi-invasive peratrial closure and transcatheter occlusion of perimembranous ventricular septal defectPurpose:The purpose of this study was to compare echocardiographic results and clinical indicators between mini-invasive peratrial closure of perimembranous ventricular septal defect(PmVSD)guided by 3-dimensional(3D)and 2-dimensional(2D)transesophageal echocardiography(TEE)and traditional percutaneous trans-catheter occlusion so as to evaluate the advantages and disadvantages of minimally invasive peratrial closure of VSD.Method:Children with PmVSD treated in cardiac surgery and pediatrics in our hospital from February 2016 to August 2018 were divided into mini-invasive group(78 cases)and transcatheter group(76 cases)according to treatment methods,and the clinical data of the two groups were retrospectively analyzed.All patients were diagnosed according to the results of TTE,routine electrocardiogram and blood tests were performed.The inclusion criteria and exclusion criteria were in accordance with relevant reports.All patients were followed up with TTE after closure.In the miniinvasive group,children weighted more than 15kg received 3D-TEE guided occlusion.Intraoperative TEE was used to assess the zone of the VSD,it was then further analyzed in 3D to determine the location,shape and size.Children weighted less than 15kg underwent 2D-TEE guided occlusion using a transesophageal probe designed for children.The inner diameter of the defect was observed and evaluated from the longitudinal axis of the left ventricle(LV)and the four-chamber view.The distance from the defect to the aortic valve was assessed from the longitudinal axis of LV and five-chamber views.In this process,narrow-angle real-time imaging,multi-plane imaging,full volume imaging and color doppler flow imaging(CDFI)were used,CDFI was used to measure the flow direction and regurgitation.A series of data obtained from intraoperative TEE were used to determine the appropriate occluder and the location for implantation.The tricuspid valve movement was monitored by TEE when the delivery system passed through the tricuspid valve into the right ventricle to occlude the VSD.The method of the transcatheter group was the same as relevant reports.TTE and X-ray were used to check the effection after the occlusion.All patients,including the transcatheter group,were followed up with TTE after the clousure of VSD.Complications including residual shunt,pericardial effusion,valvular regurgitation,device displacement or embolism,and valvular injury were examined.The patients were routinely followed up for a maximum of two years and their data were recorded.Categorical variables were expressed as frequency or percentage,and continuous variables were expressed as mean±standard deviation.The t test was used to compare the differences in measured data between two groups and tukey test for multigroup.P<0.05 was considered statistically significant.The success rate of treatment,conventional echocardiography data,postoperative complications and operation time were compared between the two groups.Results:All patients successfully completed VSD occlusion during the study period.There were no significant differences in median age and body weight between the two groups.In the mini-invasive group,78 patients underwent TEE guided closure via z-shaped probe assisted or non-probe assisted direct delivery system.Fifty-three symmetrical blockers,21 small waist blockers and four eccentric blockers were used.Patients had a mean age of 5.0 years(1-12 years)in the mini-invasive group and 5.5 years(3-14 years)in the transcatheter group,the mean weight wasl5.10 kg(8.56-33.01kg)in the mini-invasive group and 17.00 kg(10.0-36.01kg)in the transcatheter group.In the 78 patients of the mini-invasive group,the mean VSD outlet diameter was 0.35±0.12cm,the mean VSD inlet diameter was 0.51 ±0.20cm,and the mean size of the occluder was 6.2±0.7mm.The respectively measured data of transcatheter group were 0.34±0.12cm,0.52±0.10cm and 6.0±0.8mm.There was no significant difference in VSD size and occluder size between the two groups.The mean intracardiac operation time was 14±5min in the mini-invasive group and 16±6min in the transcatheter group.The number of occluders redeployed and residual shunt was 5 and 3 in the mini-invasive group and 9 and 5 in the transcatheter group.The mini-invasive group had shorter intracardiac operation time and fewer cases of occluder redeployment,residual shunt,and immediate tricuspid regurgitation.The operation time of minimally invasive group was slightly longer.Echocardiography showed that the major recent complications in the mini-invasive group were residual shunt,pericardial effusion and tricuspid regurgitation.During follow-up,the most common complication identified by TTE was tricuspid regurgitation.There were no cases of occlusion displacement,valve injury,malignant arrhythmia,hemolysis or death.In addition,according to TTE data,the patient’s intracardiac structure improved.Conclusions:Two-and three-dimensional echocardiography were feasible monitoring tools during minimally invasive peratrial closure of PmVSD.It has high success rate and low level of complications.The short and mid-term follow-up showed satisfactory results in the complications and effection of occlusion compared to transcatheter occlusion group.Part Ⅲ Value of speckle tracking echocardiography for evaluating of right ventricle function after minimally invasive closure of ventricular septal defectObjective:To evaluate the effection of mini-invasive per-ventricle closure of VSD on right ventricle function by two-dimensional speckle tracking echocardiography(2D-STE)technique.Methords:A total of 32 patients with VSD who underwent TEE guided mini-invasive per-ventricle closure in the cardiac surgery department of our hospital from April 2017 to August 2019 were selected.Most of the patients’VSD were intracristal and subartertial type.Exclusion criteria:arrhythmia,obesity,intercostal stenosis,postoperative residual shunt and other poor image quality situation.Offline analysis software was PHILIPS workstation QLab,the latest version.Clear two-dimensional images were collected by skilled physicians and ultrasonic parameters were measured,mainly including:M echocardiography measuring tricuspid annular plane systolic excursion(TAPSE)in apical four-chamber view;Right ventricular fractional area change(RVFAC)was calculated in two-dimensional echocardiography.The frame frequency of the apical four-chamber section was enough for 2-D dynamic images and the data was stored in DICOM format.Then,Qlab software was used for off-line analysis to obtain the speckle tracking parameters of right ventricle.The software actively tracked the displacement of cardiac spot to obtain the global longitudinal strain of right ventricle(RVGLS)and the longitudinal strain of the right ventricular free wall(RVFWLS).Some postoperative patients were connected to the electrocardiogram,and the three-dimensional volume imaging of the apical four-chamber section of the right ventricle was collected through the X5-1 probe with HM ACQ mode,and then entered the Qlab workstation for 3D Auto RV data analysis.Data related to right ventricular function were measured in the minimally invasive group at 1 week,1 month,3 months and 6 months after occlusion,including RVFWLS,RVGLS,TAPSE and RVFAC.All data were input and analyzed by SPSS 25.0 statistical software,quantitative data were described by mean ±standard deviation,classified data were represented by case number and percentage,t test for comparation and Pearson analysis was used for the relationship between two variables,P<0.05 was statistically significant.Results:The overall function of right ventricle(TAPSE,RVFAC and RVGLS)was not affected by minimally invasive surgery.The early decrease of RVFWLS indicated that the systolic function of right ventricle free wall was slightly affected after surgery,and recovered 1 month later.The 3D Auto RV can show the location of puncture point,and the overall spect tracking analysis of the right ventricle needs further development of the software.Correlation analysis showed that TAPSE and RVFAC were significantly correlated with RVGLS and RVFWLS.Conclusion:The 2D-STE can accurately evaluate the function changes of right ventricle after mini-invasive per-ventricle closure of VSD.