<div>Title page</div><div>Felt Sandwich Exclusion for Apical Multiple Muscular Ventricular Septal
Defects</div><div>Kota Agematsu, Mitsugi Nagashima, Masahiro Kaneko,</div><div>Yoshiharu Nishimura</div><div>Department of Cardiovascular Surgery, Wakayama Medical University,
811-1, kimiidera, wakayama-city, wakayama, Japan</div><div>Corresponding author Kota Agematsu</div><div>No funding is related to this case report</div><div>No disclosure of conflict of interest</div><div>The Institutional Review Board in our institute has reviewed this case
report and approved publication</div><div>Informed consent has been obtained from the patient’s family</div><div>Introduction</div><div>Surgical treatment for apical muscular ventricular septal defects (VSDs)
remains challenging, because there are many variations in the location
where the VSDs open, and it is hard to visualize and close VSDs using
the transatrial approach, especially in small body patients. For some
patients with muscular VSDs that cannot be closed, pulmonary artery
banding is indicated, but the outcome of this procedure is uncertain.
Some surgical closure techniques
for VSDs have been reported, but the outcomes of these techniques for
the lesion are also not definitive [1-3]. In this report, we present
the clinical case of a patient who received effective surgical treatment
for apical muscular VSDs.</div><div>Clinical summary</div><div>A 5-month-old girl who weighed 4.98 kg had been diagnosed with
perimembranous and muscular VSDs, atrial septal defect (ASD), and
pulmonary hypertension due to high pulmonary blood flow. Preoperative
catheter examination showed that the ratio of pulmonary to systemic
blood flow (Qp/Qs) was 2.3 and pulmonary to systemic blood pressure
ratio was 0.86. This patient received transatrial VSDs closure, both
perimembranous and muscular, as well as ASD closure in the first
operation. Postoperative catheter examination revealed a Qp/Qs of 2.4
and sustained pulmonary hypertension. Postoperative echocardiography
indicated moderate tricuspid valve regurgitation and residual ASD. To
relieve pulmonary hypertension, we performed a second operation almost 2
months after the first operation. We planned to carry out muscular VSDs
exclusion closure, tricuspid valve repair, and ASD closure. In case of
uncontrolled pulmonary blood flow by VSD exclusion, we also planned for
additional pulmonary artery banding. Before surgery, we roughly detected
the channels of the VSD in the cardiac apex using computed tomography
(Figure 1) and estimated part of the exclusion area. During the second
operation, we established cardiopulmonary bypass and obtained cardiac
arrest. We repaired the tricuspid valve and also directly closed the
residual ASD. We did not visualize the muscular VSDs through the right
atrium, and closing the VSDs through the right atrium was technically
challenging. To exclude the muscular VSDs, we performed the felt
sandwich technique on the cardiac apex where channels of VSDs were
located (Figure 2). After aortic de-clamping, normal heart rhythm was
obtained, and weaning from cardiopulmonary bypass was uneventful.
Transesophageal echocardiography showed a reduced trans-VSD shunt as
compared with that presented before the closure of VSDs. After the
patient was weaned from cardiopulmonary bypass, her Qp/Qs was less than
1.2, and pulmonary band was not performed. The patient was discharged
from the hospital without any complications. Postoperative
echocardiography showed a tiny muscular VSD shunt and mild pulmonary
hypertension, and postoperative catheter examination showed a Qp/Qs of
1.02 and mild pulmonary hypertension, in which the ratio of pulmonary
arterial pressure to systemic pressure was 0.4. the patient was placed
on antipulmonary hypertensive medication.</div><div>Discussion</div><div>The optical diagnosis and treatment of muscular VSDs remains
indeterminate. Muscular VSDs exist on various parts of the ventricular
septum, and it is hard to visualize the VSD channel in the coarse
trabeculations of the right ventricle, not only on preoperative images
but also via direct vision during the operation. However, computed
tomography images obtained before the operation are useful as a
reference, and in our case, a surgical strategy of apical VSDs sandwich
exclusion could be planned while referring to the preoperative image.</div><div>Although some surgical approaches, including intraoperative device
closure [4] and the sandwich technique, have been reported, optimal
outcomes have not yet been obtained. Device-related complications such
as device embolization, tricuspid or aortic valve damage, and recurrent
defects may occur. The ventricle septal sandwich technique is simple and
effective; however, the use of numerous felt patches on the ventricular
septum disturbs the movement of the ventricular septum, resulting in
impairing ventricular function [2]. In addition to surgical
techniques, visualization of muscular VSDs is an important factor in VSD
treatment. Apical right or left ventriculotomy has been used to
visualize the apical muscular VSDs for closure [5], but
ventriculotomy might lead to late ventricular dysfunction, aneurysmal
formation, and ventricular arrhythmias in the future.</div><div>Because muscular VSDs can be located anywhere on the ventricular septum,
a definitive surgical closure method cannot be established. The choice
of surgical technique should be based on where the VSDs are located.
In determining the best surgical
technique, it is important to determine preoperatively where the VSD
channels are. In our presented case, computed tomography was useful for
locating the VSDs and which channels were near the ventricular apex, and
these VSDs were estimated to be excluded by the using felt sandwich
technique exteriorly. This technique may be one choice for surgical
closure for muscular VSDs.</div><div>References</div><div>1.Kitagawa T, Durham III LA, Mosca RS, Bove EL Techniques and results in
the anagement of multiple ventricular septal defects. J Thorac
Cardiovasc Surg 1997;115:848-56</div><div>2.Ootaki Y, Yamaguchi M, Yoshimura N, Oka S, Yoshida M, Hasegawa T
Surgical management of trabecular ventricular septal defects: The
sandwich technique. J Thorac Cardiovasc Surg 2003;125:508-12</div><div>3.Yoshimura N, Matsuhisa H, Otaka S, Takuro MIsaki, et.al Surgical
management of multiple ventricular septal defect:The role of the felt
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al. Outcomes of intraoperative device closure of muscular ventricular
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right ventriculotomy for closure of
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