<div>A study on eccentric occluder via ultra minimal incision of Doubly
Committed Subarterial Ventricular Septal Defects</div><div>Qiang Gao[1], Jie Jin[1], Zewei Zhang[1], Lianglong
Ma[1], Jianhua Li[1], Jiangen Yu[1]</div><div>[1]: Department of Cardiac Surgery&amp; Heart Center, The Childern’s
Hospital, Zhejiang University School of Medicine, National Clinical
Research Center for Child Health, Hangzhou 310052, China</div><div>Corresponding author: Zhang Zewei, Email:<i>zeweiz@zju.edu.cn</i></div><div>Data availability statement: All data included in this study are
available upon request by contact with the corresponding author</div><div>Funding: None.</div><div>Conflict of Interest: None.</div><div>Abstract: Object: To compare the clinical data of sternotomy and left
intercostals incision, combined with the literature, to provide the best
surgical incision for committed subarterial ventricular septal
defect（DCS-VSD）. Methods: From July 2016 to July 2020, a total of 117
cases of occlusion surgeries for DCSVSD, which guided by transoesophagel
echocardiography(TEE) were completed, including 34 cases with sternotomy
incision and 83 cases with left intercostal incision. Statistics and
analysis of the operation and follow-up. Results: 115 cases successfully
occluded, the successful rate was 98.29%, and 1 case failed in each
group. Pericardial effusion occurred in 5 children after the drainage
device was removed, and the pericardial effusion disappeared after
diuretic treatment. There was no statistical difference between the two
groups in operation time, occlusion time, thoracotomy time and
postoperative hospital stay. All the children recovered and were
discharged from the hospital, and were followed up for 2-30 months after
operation. Conclusion: TEE-guided intercostal DCS-VSD occlusion is safe
and effective. There is no statistical difference between two approach
with the operation time, chest opening and closing time, occluder
placing time, and postoperative hospital staying. At the same time, the
surgical incision by intercostal incisionis smaller and the operation
invasion is less, it is a surgical approach which worth to develop.</div><div>Keywords: Doubly Committed Subarterial Ventricular Septal Defects;
minimally invasive occlusion; Interventional surgery</div><div>Ventricular septal defect is the most common congenital heart diseases.
As one kind of VSDs doubly committed subarterial ventricular septal
defect (DCS-VSD) is very high incidence in Asians, reaching 25%
[1]. For a long time, DCS-VSD can only be treated by cardiopulmonary
bypass surgery. Although there have been reports of catheter
interventional treatment, the operation is complicated and the failure
rate is high. Very few hospitals carry out[2]. In recent years, TEE
guided surgical occlusion of ventricular septal defect has made great
progress. The application of eccentric occluder has made minimally
invasive interventional therapy of DCS-VSD widely available [3,4,5].
TEE-guided transthoracic occlusion, without cardiopulmonary bypass
cardiopulmonary bypass, and no radiation, is an excellent surgical
stratege. At present, the surgical approaches for DCS-VSD occlusion
surgery mainly include sternum incision, intercostal incision on the
left side and underarm incision [3, 6, 7, 8]. This study reports a
comparison of the two surgical approaches, which are sternum incision
and intercostal incision, combined with the literature, to analyze their
respective advantages and disadvantages, and discuss which method is a
better surgical approach.</div><div>Materials and Methods</div><div>Clinical data</div><div>From July 2016 to July 2020, we implemented 117 cases of DCS-VSD
closure. 34 children underwent by sternotomy insicion, including 23
males and 11 females, aged 13-163 months(Median age 34 months), weight
7.6-49.8 (15.61±8.07) kg, diameter of VSD is about 2.2-8 (4.00±1.44) mm.
There were 83 children underwent by small incision on the left
intercostal, including 57 males and 26 females, aged 12-137 months
(Median age 35 months), weighing 8.9-28（15.14±4.69）kg, and diameter of
VSD is about 2-6（3.80±1.03） mm.</div><div>Methods</div><div>Institutional Review Board: This study is a retrospective study of
clinical surgery and does not require IRB approval</div><div>Fully inform the child’s guardian of the operation method and operation
risk before the operation, and sign the operation informed consent.</div><div>Preventive use of cefuroxime during perioperative period. The children
were routinely anesthetized, and TEE was used to assess the size of
DCS-VSD and the performance of the aortic valve. If the size of DCS-VSD
is appropriate, and the right aortic valve is slightly prolapsed or the
aortic valve is slightly regurgitated, consider occlusion, otherwise we
switched to open-heart surgery. We chosed the size of occluder
asdiameter of DCS-VSD+ 2[Fig 1,2], which is eccentric (Produced by
Shanghai Shape Menory Alloy Co., Ltd). The operation is performed by 3
senior chief physicians, and the surgical incision is determined
according to the habits of the chief surgeon.</div><div>After sterilized drapes, the sternum incision is made in the lower part
of the sternum, normall is about 3-4cm, then the sternum is sawed into
the mediastinum, pericardium is opened and suspended. A small
intercostal incision is generally made on the left 2-3th intercostal
space of the sternum, and is about 1cm[Fig 3]. After the thymus is
pushed aside, the pericardium can be opened. After exposing the heart,
we use tweezers to locate the position of puntcure on the anterior wall
of the right ventricle. We choose the position for puncture on right
ventricular surface, which is closest and minimum angle to the shunt
flow of VSD. The suture purse is reserved on the puncture site. 1mg/kg
heparinized after the trocar is punctured in the purse. After removing
the inner core, the steel wire is inserted through the lumen of the
trocar. Under the guidance of TEE, the wire was delivered to the left
ventricle through the defect. Then we withdraw the trocar, deliver the
delivery sheath to the left ventricle along the wire, then exit the wire
and the inner sheath of the delivery tube, then dock the sheath with the
occluder and the delivery sheath. Under TEE monitoring, we release the
left disc first, then observe the position of the eccentric marker, and
turn the occluder clockwise to make the marker face down and aim at the
distal end of the aortic valve. We pull back the left disc to make it
close to the ventricular septum, continue to retract the sheath to the
right ventricle, and then release the occluder waist and right
ventricular disc[Fig 4]. TEE simultaneously checked for residual
shunt, outflow tract obstruction, aortic pulmonary valve regurgitation,
and ECG monitoring for arrhythmia. If any abnormality is found, adjust
or replace the occluder immediately. If there is no abnormality, the
occluder is released after the push-pull test. Withdraw the delivery
tube and tie the purse. After checking that there is no bleeding, place
a drainage device[Fig 5] and close the chest. Take aspirin
anticoagulant treatment for 3 months after operation.</div><div>Postoperative cardiac echo, chest radiographs and electrocardiograms to
assess cardiac function, valve regurgitation, occluder status, and the
presence of complications such as arrhythmia and pericardial effusion.</div><div>Statistical analysis</div><div>Data on age was expressed as the range and median. Data on weight, DCVSD
size, procedure relating time and the length of hospital stay were
expressed as range and the mean ± standard deviation . All data were
analysed using SPSS 19.0 statistical software.</div><div>Results</div><div>117 cases of DCS-VSD were successfully occluded in 115 cases, the
success rate was 98.29%, and there was one case in each group failed.
One child was 11 months old, with a DCS-VSD, size of 6 mm, using a small
intercostal incision, and using a No. 8 eccentric occluder during the
operation. There was still a residual shunt of 2.5 mm, and he was
changed to operate cardiopulmonary bypass surgery. One child was 49
months old, with a DCS-VSD, size of 7 mm, using a sternum incision, and
using a No. 9 eccentric occluder during the operation. The occlude was
displaced during the releasing of the occluder and was changed to
operate cardiopulmonary bypass surgery[Fig 6]. The occluding of the
other children went smoothly. There were no residual shunts, aggravated
valve regurgitation, outflow tract obstruction, and no serious
complications such as complete atrioventricular block. The total
operation time of the sternal incision group was 18-71 (46.58±13.58)
min, of which the occluding time was 5-38 (13.83±9.17) min, chest
switching time 24-54 (36.00±9.80) min. Three children had pericardial
effusion after operation, the length of postoperative hospital stay was
7 days，11 days，and 20 days. The postoperative postoperative hospital
stay of the remaining children was 4-8 (6.09±1.4) days. The total
operation time of the small intercostal incision group was
24-72(47.54±12.06) min, of which the occluding time was 5-37(16.16±8.01)
min, and the chest opening and closing time was 14-59(31.56±9.58) min.
Pericardial effusion occurred in 2 cases after operation, the length of
postoperative hospital stay was 13 days，23 days. The postoperative
hospital stay of the remaining children was 3-9(5.79±1.45) days after
operation. All cases were followed up for 2-30 months after the
operation. They recovered smoothly without complications.</div><div>Compared with the small intercostal incision group, the sternal incision
group had no statistically significant difference in operation time,
occluding time, chest opening time, and postoperative hospital stay.</div><div>Disscusion</div><div>Doubly committed subarterial ventricular septal defect, due to its
proximity to the aortic valve and pulmonary valve, can easily lead to
valve prolapse and regurgitation, and the self-healing rate is extremely
low, so timely surgical treatment is required [9]. Traditional
surgical treatment with cardiopulmonary bypass is definitely effective,
but the surgical trauma is heavy. Incardiac catheterization
interventional therapy, it is difficult to operate, and there are few
reports. At the same time, it is exposed to radiation and the amount of
radiation is large. Surgical esophageal ultrasound-guided interventional
therapy provides new ideas for minimally invasive treatment of DCS-VSD
[10].</div><div>Originally, obvious aortic valve prolapse and reflux were
contraindications for DCVSD occlusion by device technique, but we have
different experience. Previously it was reported that even mild aortic
prolapse can be associated with an occlusion failure, if a hybrid
approach is performed[11,12,13]; in our series however, children
even with a mild aortic prolapse received a successful transthoracic
device closure, without further valve prolapse and valve regurgitation.
Therefore, we guess that there is no general contraindication for device
closure in case of a mild aortic valve prolapse or if preoperative
evaluation shows a tear-drop prolapsed[14] or a mild aortic valve
regurgitation.</div><div>According to the statistical data of this study, it is found that the
small left intercostal incision for occluding DCS-VSD is no different
from the lower sternal incision, but the intercostal incision does not
need to cut the sternum, which avoids the occurrence of sternal
hemorrhage and chicken breast, with less drainage after surgery. The
surgical incision of intercostal about 1cm is smaller than the incision
of the lower sternum which at least 2-5cm[Fig 7,8]. In addition,
since the DCS-VSD is mostly located in the 2-3 intercostal space on the
left margin of the sternum, after the TEE is positioned, the puncture
sheath can enter almost perpendicular to the VSD, the puncture path is
shorter, and it is easier to establish a delivery system compared to the
incision of the lower sternum, so that it has more advantages. There are
also reports about occluding DCS-VSD through the left underarm and right
underarm. The surgical incision is at least 2-3cm, the average operation
time is about 60min, and the intracardiac operation time is about 20min
[6], both of which are longer than intercostal incisions. Of course,
because the underarm incision has not been carried out in our hospital,
there is no comparability of operation time and other data performed by
different doctors, so it can only be used as a reference. But at least
compared with the axillary approach, the small left intercostal incision
has a small surgical incision, no need to open the intercostal space,
less trauma, and also has more advantages.</div><div>In this study, there were 2 failure cases. One child was 11 months old
and had a DCS-VSD, diameter of 6 mm. After using the No. 8 eccentric
occluder, there was still a residual shunt of 2.5 mm, which was changed
to cardiopulmonary bypass surgery. For residual shunts, general
experience is that small shunts with a diameter of &lt;1.5mm and
a TEE measurement velocity of flow &lt;2.5m/s can heal by
themselves [15]. In this case, the residual shunt flow is large,
there is low possibility of self-closing, and the child is too young.
Enlarging the occluder size will affect the aortic valve function, so
the final decision was to switch to cardiopulmonary bypass surgery
during the operation. The other patient was 49 months old and had a
DCS-VSD, diameter of 7 mm. During the operation, a No. 9 eccentric
occluder was used. The occluderwas displaced during the releasing of the
occluder, and the operation was changed to cardiopulmonary bypass
surghery. We consider that the residual shunt and occluder displacement
have a certain relationship with the ultrasonic measurement method. In
the case of slight aortic valve prolapse, because the prolapsed valve
will cover part of the defect, measuring the size of the VSD according
to the blood flow will often lead to a smaller measurement diameter,
which leads to choosea smaller occluder, and caused residual shunt or
displacement. Therefore, for patients with valvular prolapse, measuring
the size of the defect should measure the distance from the defect to
the root of the valve on a two-dimensional image, rather than simply
measuring the size of Doppler blood flow. The experience of the
ultrasound doctor is crucial to the operation. Good positioning can
significantly shorten the operation time. Accurate measurement can
reduce the occurrence of residual leakage and displacement. If a small
intercostal incision is used but the cardiopulmonary bypass surgery is
finally switched, there will be two surgical scars after the operation,
which is contrary to the original intention of minimally invasive
surgery. Therefore, for children with large DCS-VSD diameter, small age,
and inaccurate defect measurement, it is still recommended to use the
lower sternum incision. When the occlusion surgery is changed to
cardiopulmonary bypass surgery, the operation can be completed by
extending the original incision.</div><div>Conclusion</div><div>In summary, the small intercostal incision to occlude DCS-VSD is a safe,
effective, small trauma, and cosmatic incision, and it is worth
promoting as a conventional minimally invasive surgery for DCS-VSD. We
will also further increase the sample pool, improve postoperative
long-term follow-up and other related work, and provide more
comprehensive clinical data.</div><div>References</div><div>[1] Li Hongxin, Guo Wenbin, Fei Liang, Hai-Zhou Zhang, Mei Zhu,
Wen-Long Zhang. Perventricular device closure of a doubly committed
juxtaarterial ventricular septal defect through a left parasternal
approach: midterm follow-up results[J]. J Cardiothorac Surg, 2015,
10: 175-183. DOI: 10.1186/s13019-015-0376-9.</div><div>[2] Gu M, You X, Zhao X, Zheng X, Qin YW. Transcatheter device
closure of intracristal ventricular septal defects[J]. Am J Cardiol.
2011 Jan;107(1):110-3. doi: 10.1016/j.amjcard..2010.08.053.</div><div>[3] Jin Yu, Lianglong Ma, Jingjing Ye, Zewei Zhang, Jianhua Li,
Jiangen Yu, Guoping Jiang. Doubly committed ventricular septal defect
closure using eccentric occluder via ultraminimal incision[J]. Eur J
Cardiothorac Surg. 2017 Oct 1;52(4):805-809. doi: 10.1093/ejcts/ezx269.</div><div>[4] Chen Zhao Yang, Cao Hua, Ma Yuan Ji, Chen Qiang, Pan Wen Zhi,
Chen Wan Hua, et al. Transfemoral and perventricular device occlusions
and surgical repair for doubly committed subarterial ventricular septal
defects[J]. Ann Thorac Surg. 2015 May;99(5):1664-70. doi:
10.1016/j.athoracsur.2015.01.051.</div><div>[5] Zhao Yang Chen, Yuan Ji Ma, Wen Zhi Pan, Qiang Chen, Wan Hua
Chen, Chang Xiong, et al. Transfemoral Device Occlusion and Minimally
Invasive Surgical Repair for Doubly Committed Subarterial Ventricular
Septal Defects[J]. Pediatr Cardiol. 2015 Dec;36(8):1624-9. doi:
10.1007/s00246-015-1207-4.</div><div>[6] Sijie Zhou, Liyun Zhao, Taibing FaN, Bin Li, Weijie Liang, Haoju
Dong, et al. Perventricular device closure of doubly committed
sub-arterial ventricular septal defects via a left infra-axillary
approach[J]. J Card Surg. 2017 Jun;32(6):382-386. doi:
10.1111/jocs.13155.</div><div>[7] Huang C, Yu T, Zhang X. Doubly Committed Subarterial Ventricular
Septal Defects Closure Using Minimal Mid-Partial Sternotomy[J]. Ann
Thorac Cardiovasc Surg. 2019 Jun 20;25(3):172-175. doi:
10.5761/atcs.oa.18-00184.</div><div>[8] Li Hongxin, Guo Wenbin, Fei Liang, Hai-Zhou Zhang, Mei Zhu,
Wen-Long Zhang. Perventricular device closure of a doubly committed
juxtaarterial ventricular septal defect through a left parasternal
approach: midterm follow-up results[J]. J Cardiothorac Surg. 2015
Nov 26;10:175. doi: 10.1186/s13019-015-0376-9.</div><div>[9] Shu Zhang, Da Zhu, Qi An, Hong Tang, Dajiang Li, Ke Lin.
Minimally invasive perventricular device closure of doubly committed
sub-arterial ventricular septal defects: single center long-term
follow-up results[J]. J Cardiothorac Surg, 2015, 10: 119. DOI:
10.1186/s13019-015-0326-6.</div><div>[10] Gui-Can Zhang, Qiang Chen, Hua Cao, Liang-Wan Chen, Li-ping
Yang, Dao-zhong Chen. Minimally invasive perventricular device closure
of ventricular septal defect in infants under transthoracic
echocardiograhic guidance: feasibility and comparison with
transesophageal echocardiography[J]. Cardiovasc Ultrasound. 2013 Mar
11;11:8. doi: 10.1186/1476-7120-11-8.</div><div>[11] Ke Lin, Da Zhu, Kaiyu Tao, Changping Gan, Hong Tang, Yuan Feng,
Qi An. Hybrid perventricular device closure of doubly committed
subarterial ventricular septal defects: mid-term results[J].
Catheter Cardiovasc Interv. 2013 Sep 1;82(3):E225-32. doi:
10.1002/ccd.24869.</div><div>[12] Silin Pan, Quansheng Xing, Qian Cao, Pingshan Wang, Shuhua
Duan, Qin Wu, Kefeng Hou. Perventricular device closure of doubly
committed subarterial ventral septal defect through left anterior
minithoracotomy on beating hearts[J]. Ann Thorac Surg. 2012
Dec;94(6):2070-5. doi: 10.1016/j.athoracsur.2012.05.070.</div><div>[13] Qiang Chen, Liang-Wan Chen, Qi-Min Wang, Hua Cao, Gui-Can
Zhang, Dao-Zhong Chen. Intraoperative device closure of doubly committed
subarterial ventricular septal defects: initial experience[J]. Ann
Thorac Surg. 2010 Sep;90(3):869-73. doi:
10.1016/j.athoracsur.2010.06.022.</div><div>[14] K Mori, S Matsuoka, K Tatara, Y Hayabuchi, M Nii, Y Kuroda.
Echocardiographic evaluation of the development of aortic valve prolapse
in supracristal ventricular septal defect[J]. Eur J Pediatr. 1995
Mar;154(3):176-81.</div><div>[15] SONG Shu-bo;FAN Tai-bing;LI Bin;LIANG Wei-jie;DONG Hao-ju;WU
Kai-yuan;HAN-Yu. Clinical experience and short-term out-come for
minimally invasive occlusion in patients with peri-membranous
ventricular septal defect via right subaxillary route[J]. Chin Circ
J, 2016, 31(3): 272-275. DOI: 10.3969/j.issn. 1000-3614.2016.03.016.</div>