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\begin{document}

\title{Ventricular septal intramyocardial dissection after cardiac fibrosarcoma
excision}



\author[1]{Gang Wang}%
\author[2]{Jianhua Wang}%
\author[1]{Gengxu Zhou}%
\author[1]{Zhichun Feng}%
\affil[1]{Southern Medical University}%
\affil[2]{Chinese PLA General Hospital}%


\vspace{-1em}



  
  \date{June 06, 2024}


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\selectlanguage{english}
\begin{abstract}
Intramyocardial dissection following cardiac tumor excision is uncommon.
The evidence available is limited to few case reports.
\textsuperscript{1} Herein,we report an infant with large cardiac
fibrosarcoma arising from the interventricular septum and underwent
surgical excision.One month after surgery echocardiography revealed a
cystic dissection located in the interventricular septum with residual
shunts within the ventricular chambers. we performed conservative
strategy due to the high surgical risk, difficulty of interventional
therapy and hemodynamic stability.%
\end{abstract}%



\sloppy


Ventricular septal intramyocardial dissection after cardiac fibrosarcoma
excision

Gang Wang MM\textsuperscript{1,2,+},Jianhua Wang
MD\textsuperscript{3,+},Gengxu Zhou MD\textsuperscript{1,2} ,Zhichun
Feng MD\textsuperscript{1,2,*}

\textsuperscript{1}Second Clinical Medical College,Southern Medical
University,Guangzhou,China.

\textsuperscript{2}Department of Pediatrics,The Seventh Medical Center
of the PLA General Hospital, Beijing,China.

\textsuperscript{3}Department of Ultrasound,The Seventh Medical Center
of the PLA General Hospital, Beijing,China.

+ Gang Wang and Jianhua Wang are co-first authors on this work

\textsuperscript{*}Correspondence:Zhichun Feng,Department of Pediatrics,
The Seventh Medical Center of the PLA General
Hospital,Beijing,100700,China;Second Clinical Medical College,Southern
Medical University,Guangzhou,510515,China.

E-mail:fengzc111@126.com

\textbf{Abstract}

Intramyocardial dissection following cardiac tumor excision is uncommon.
The evidence available is limited to few case
reports.\textsuperscript{1} Herein,we report an infant with large
cardiac fibrosarcoma arising from the interventricular septum and
underwent surgical excision.One month after surgery echocardiography
revealed a cystic dissection located in the interventricular septum with
residual shunts within the ventricular chambers. we performed
conservative strategy due to the high surgical risk, difficulty of
interventional therapy and hemodynamic stability.

\textbf{Key words} : Intramyocardial dissection,Cardiac tumor

\textbf{Case presentation}

A 3-month-old female infant presented to our hospital with one month
history of dyspnea.Transthoracic echocardiography demonstrated a large
tumor mass(50mm\selectlanguage{ngerman}×42mm) originated from the interventricular septum and
filled the bilateral ventricular chambers(Figure 1). The patient
underwent surgical resection of the tumor via the median sternotomy
under cardiopulmonary bypass(CPB). During the operation, we found the
tumor infiltrated the myocardium and the border between the tumor and
the myocardium was unclear. Eventually we completely resected the tumor
including part of myocardium. Interventricular septum was repaired with
a bovine pericardium patch. The patient was weaned from the CPB and a
postoperative transthoracic echocardiography confirmed no residual tumor
and good ventricular function. Pathological examination revealed
fibrosarcoma.

At one month follow up transthoracic echocardiography revealed a cystic
dissection(43mmx32mm) located in the interventricular septum(Figure
2).This cystic dissection connected to the left ventricle through a
4.5mm defect,and to the right ventricle through several small holes of
its thin walls(Figure 3,Movie S1).We defined this case as ventricular
septal intramyocardial cystic dissection with residual shunts within the
ventricular chambers due to the separation of myocardial layers and
communication with ventricular chambers after operation. we performed
conservative strategy, because of the high surgical risk, difficulty of
interventional therapy and hemodynamic stability. At 9 months of
follow-up, transthoracic echocardiography demonstrated the original
cystic dissection was slightly reduced and the shunts between the cystic
dissection and right ventricle disappeared. There was bidirectional
shunt between the cystic dissection and left ventricle through the
defect(Figure 4,Movie S2).The patient was asymptomatic and cardiac
function was good. We continue to follow up the patient.

\textbf{Discussion}

Intramyocardial dissection is rare and mostly secondary to myocardial
infarction.In a meta-analysis\textsuperscript{2} of the literature
including 40 cases of Intramyocardial dissection,32 cases after
myocardial infarction and in 8 patients following
trauma.\textsuperscript{3-4} In 5 patients, communication between the
left and right ventricles was found. In-hospital mortality was 23\%.
Multivariate analysis showed that the strongest independent predictor of
mortality was EF\textless{}35\%.\textsuperscript{2} There also were a
few reports of intramyocardial dissection secondary to the cardiac
echinococcosis.\textsuperscript{5-6} Intramyocardial dissection
following cardiac tumor excision is uncommon,the evidence available is
limited to few case reports. This complication is due to destruction of
the integrity of the interventricular septum and entry into the
ventricular cavities during resection of the tumor. In our patient, only
very thin endocardium separated the tumor from the ventricular cavity,
entering into the left ventricular cavity when the tumor was
dissected.we repaired the septum with a bovine pericardium patch. It may
be due to the fragility of the myocardial tissue leading to the suture
avulsion, followed by the formation of ventricular septal
intramyocardial dissection and residual shunt.

The optimal management of intramyocardial dissection is controversial
due to its rarity and lack of supportive evidence. Most of the
experience come from studies of intramyocardial dissection after
myocardial infarction. Treatment includes surgery, intervention and
conservative medical therapy. In a systematic review of patients with
postinfarction intramyocardial dissection, the mortality rate was
significantly higher in the medical group versus surgical-treated group
(85.7\% versus 42.3\%).\textsuperscript{7} For our patient, the age was
only 3 months, interventional treatment was difficult, and the risk of
reoperation was high. Most importantly, the patient was asymptomatic and
hemodynamically stable.So we performed conservative strategy. During
follow-up, we found that the cystic dissection was slightly reduced and
the shunts between the cystic dissection and right ventricle
disappeared. We will continue to follow up the patient.

Echocardiography is a noninvasive and simple technique.It has a
important role in diagnosing intramyocardial dissection.
Echocardiography

can evaluate the size and location of the intramyocardial dissection,
detect flow within the cavity,assess heart function, thus assisting in
the decisions about treatment strategy.We can learn from our case that
when resecting tumors located in the ventricular septum, we should try
to ensure the integrity of the ventricular septum and avoid entering the
ventricular cavity. After resection, we should carefully check and
repair the ventricular septum. For benign cardiac tumors can be partial
resection to prevent damage to important structures.\textsuperscript{8}

\textbf{References}

\begin{enumerate}
\tightlist
\item
  Wenjuan Bai,Lijun Zeng,Li Rao.A residual intramyocardial cystic
  dissection after cardiac fibroma
  resection.Echocardiography.2015;32:602-603.
\item
  Marina Leitman,Vladimir Tyomkin,Leonid Sternik,et al.Intramyocardial
  dissecting hematoma: Two case reports and a meta-analysis of the
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\item
  Maselli D,Micalizzi E,Pizio R,et al.Posttraumatic left ventricular
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\item
  Silverstein JR,Tasset MR,Dowling RD,et al.Traumatic intramyocardial
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\item
  Ahmed T,Al-Zaibag M,Allan A,et al.Cardiac echinococcosis causing acute
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\item
  Unal M, Tuncer C, Serce K, et al.A cardiac giant hydatid cyst of the
  interventricular septum masquerading as ischemic heart disease: Role
  of MR imaging.Acta Cardiol.1995;50:323-326.
\item
  Shokoufeh H,Abdollah A,Marziyeh P,et al.Postinfarction intramyocardial
  dissection,an interesting case report and systematic review.
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\item
  Padalino MA, Vida VL, Boccuzzo G, et al. Surgery for primary cardiac
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  2012;126:22\selectlanguage{english}-30.
\end{enumerate}

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