Evaluation of Left Ventricular Rotation and Twist Using Speckle Tracking Imaging in Patients with Atrial Septal Defect

Speckle tracking imaging （STI） was employed to investigate the effect of right ventricular （RV） volume and pressure overload on left ventricular （LV） rotation and twist in 35 patients with atrial septal defect （ASD）, 18 of which with pulmonary hypertension, and 21 healthy subjects serving as controls. The peak rotations of 6 segments at the basal and apical short-axises and the average peak rotation and interval time of the 6 segments in the opposite direction during early systolic phase were measured respectively. LV twist versus time profile was drawn and the peak twist and time to peak twist were calculated. LV ejection fraction （EF） was measured by Biplane Simpson. Compared to ASD patients without pulmonary hypertension and healthy subjects, the peak rotations of posterior, inferior and postsept walls at the basal level were lower （P〈0.05）, and the average counterclockwise peak rotation of 6 segments at the basal level during early systolic phase was higher （P〈0.05）, and the average interval time was delayed （P〈0.05）. LV peak twist was also lower （P〈0.05）, and had a significant negative correlation with pulmonary arterial systolic pressure （r=-0.57, P=0.001）. No significant differences were found in LVEF among the three groups. It was suggested that although RV volume overload due to ASD has no significant effects on LV rotation and twist, LV peak twist is lower in ASD patients with pulmonary hypertension. Thus LV twist may serve as a new indicator of the presence of pulmonary hypertension in ASD patients.

Improvement of the Technique for Transcatheter Closure of Atrial Septal Defect in Children

Objectives To improve experience of procedure and success rate of interventional treatment of atrial septal defect （ASD） in children, applying the technique of controlling release of devices in the pulmonary vein （controlling two disc of device opening for subsequence） in children cases with ASD who can not be occluded by regularly interventional treatment. Methods Since 2000 year 182 child cases （male 70 and 112 female） underwent the procedure of controlling release of devices in the pulmonary vein. The patients＇ age was from 2 to 14 years old （average 3.77±1.55）. The body weight was from 9 to 48 Kg （average 21.53±10.63）. When the devices were placed on the right position with difficulty and failure in some cases with short and soft rims of the defect and large defect and the angle between the device and the interval atrial septal （IAS）, It could be helpful to put the device into the left upper pulmonary vein, and to make right atrium （proximal） disc opened before the left atrium （distal） disc naturally fall down. At the end the double disc of the device clamped and stood up at the right position of the IAS. After closure of ASD, patients were followed up regularly by echocardiography, X-ray and ECG in the 1,3,6,12 month and 3,5 years. Results The successful rate of device implantation in the improving group （98.4%） was obviously higher than that in the regularly group （68%）. The techniques improved in this group with the smaller age, the lighter weight, the larger defect and the larger device comparing with the regularly group. The velocity of the pulmonary vein before occlusion procedure was （0.54±0.15）m/s; after procedure was （0.56±0.16）m/s, P 〉 0.05,there were no significant difference. All cases couldn＇t found pulmonary congestion by follow up. Conclusions The method of controlling release of device in the pulmonary vein has been used more than 5 years in the occlusion of ASD with double disc device. It is feasible and safety. The aim of the improvement is for overcoming the problem with larger ASD and the rim deficiency in the interventional procedure in children with ASD. In summary： 1. The performance of the procedure must be careful; 2. To avoid complication when put the sheath into the pulmonary vein; 3. To avoid to put the left disc into pulmonary vein too long and pull the device too much; 4. When the procedure have to operate repeatedly, the device can not be released before the position satisfactory. The improvement of the technique is needed to carry on long-term follow-up in the clinical trials.

Clinical Study on Amplatzer Occluder Device to CloseVentricular Septal Defect

Objectives To evaluate the therapeutic effect of transcatheter Amplatzer device on the closure of ventricular septal defect （VSD）. Methods Among 143 patients with VSD, 135 patients with perimembrane VSD and 2 with muscular VSD aged 2.5 -28 years old, were successfully closed with Amplatzer oeeluder device by the pereutaneous guidwire through femoral artery-VSD-femoral vein route under the guidance of fluoroscopy, ventrieulography and transthoracic echocardiography （TIE）. The diameters of the VSDs were 2.3-15.7 （6.90±2.76）mm by left ventriculography. Results The success rate of transcatheter closure of VSD with Amplatzer devices was 96%（137/143）. Minimal residual amount of shunts were found in one patient, although the shunts was decreased one month after the procedure. There were one patient who had respiratory arrest during the procedure, 7 patients（5%）had conduction disturbance, 3 patients had complete left bundle branch block, 2 patients had complete right bundle branch block, 1 patient had Ⅰ degree atrial-ventricular block and 1 patient had Ⅲ degree atr/al-ventricular block during hospitalization. The diameters of the occluder ranged from 4 to 23 （9.13±3.31）mm and were symmetrical in 122 patients and asymmetrical in 15 patients. Conclusions Transcatheter closure of the perimembranous ventrieular septal defect using Amplatzer VSD occluder device is an efficient method for patients with the perimembranous VSD. The operation is simple with a high success rate and a good effect.

Transcatheter closure of perimembranous ventricular septal defects:single centre experience in China

Ventricular septal defect （VSD） is one of the most common congenital heart malformation.As an isolated lesion, it accounts for 20% -30% of patients with congenital heart disease. Eighty percent of these defects are perimembranous involving the membranous septum and the adjacent area of muscular septum. At least 80% of these defects are small and close spontaneously, the larger defects often persist to cause significant shunt and right ventricular hypertension. Although conventional surgical repair of perimembranous ventricular septal defects （PMVSDs） is a safe, widely accepted procedure with negligible mortality. It is associated with morbidity, discomfort and a thoracotomy scar. As an alternative to surgery, a variety of devices for transcatheter closure of VSD have been developed. However, these devices were not specifically designed for this purpose and none has gained wide acceptance. Large delivery sheaths, inability to recapture and reposition, structural failure, dislodgement and embolization of the device, interference with the aortic valve resulting in aortic insufficiency and a high rate of residual shunting are the major limitations of the previously described techniques.

Long-term follow up of interventional therapy of secundum atrial septal defect

Background The percutaneous transcatheter closure of secundum atrial septal defect （ASD） is increasingly a widespread alternative to surgical closure.The aim of this study was to assess long-term results of percutaneous closure of secundum-type atrial septal defect （ASD Ⅱ）.Methods Between January 2001 and December 2005,61 patients underwent a successful percutaneous closure of ASD Ⅱ; including 25 male and 36 female.All were included in the patient study and were followed up to monitor by electrocardiogram and echocardiography,at intervals of 3 days,3 months,6 months,1 year,2 years,and 5 years after operation.Results Three days after percutaneous transcatheter septal closure （PTSC）,the right atrium diameter,right ventricular end-diastolic left-right diameter and right ventricutar end-diastolic volume （RVEDV） decreased significantly （P 〈0.05）.Right ventricular end-diastolic anteroposterior diameter （RVEDD）,right ventricular end-systolic volume （RVESV） and right ventricular ejection fraction （RVEF） also decreased （P〈0.01）.During the period from 3 to 6 months,the size of the right atrium and right ventricle returned to normal range.Three days after PTSC,the left ventricular end-diastolic diameter （LVEDD）,left ventricular end-diastolic volume （LVEDV）,left ventricular end-systolic volume （LVESV）,left ventricular-systolic volume （LVSV） and left ventricular ejection fraction （LVEF） were significantly increased （P 〈0.05）.At 1 year,the size of the left atrium,left ventricle and left cardiac function returned to normal range （P 〈0.01）.There were no deaths or significant complications during the study.At five year follow-up,all defects were completely closed and remained closed thereafter.Conclusion Transcatheter closure of ASD Ⅱ effectively eliminated the abnormal shunt and,subsequently improved the dimensions of each chamber and cardiac function.