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\begin{document}

\title{Submitral Aneurysm: Exploring a Rare Pathology}



\author[1]{Kellen Round}%
\author[1]{Jake Rosen}%
\author[1]{Colin Yost}%
\author[1]{T. Sloane Guy}%
\affil[1]{Thomas Jefferson University Sidney Kimmel Medical College}%


\vspace{-1em}



  
  \date{March 14, 2025}


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\textbf{Title} : Submitral Aneurysm: Exploring a Rare Pathology

\textbf{Authors} : Kellen Round BS\textsuperscript{1}, Jake L. Rosen
BA\textsuperscript{1}, Colin C. Yost BA\textsuperscript{1}, T. Sloane
Guy MD, MBA\textsuperscript{2}

\textsuperscript{1}Sidney Kimmel Medical College, Thomas Jefferson
University, 1025 Walnut St \#100, Philadelphia, PA 19107

\textsuperscript{2}Division of Cardiac Surgery, Department of Surgery,
Thomas Jefferson University, Curtis Bldg, Ste 620, 1015 Walnut St
Philadelphia, PA 19107

\textbf{Running Title:} Submitral Aneurysm Commentary

\textbf{Corresponding Author:}

T. Sloane Guy, M.D., MBA

Professor of Surgery

Director, Minimally Invasive \& Robotic Cardiac Surgery

1025 Walnut Street, Suite 607

Philadelphia, PA, 19107

215-955-6996

sloane.guy@jefferson.edu

\textbf{Word Count:} 1032

\textbf{Funding:} This project did not require any source of financial
support.

\textbf{Commentary} :

In their case series on outcomes of submitral aneurysm (SMA), Aggarwal
et al. provide one of the largest known characterizations and follow-up
studies of this infrequently reported pathology\textsuperscript{1}. We
commend the authors for offering this unique case series and believe it
will generate further dialogue on the topic. The series details the
presentation, etiologies, and outcomes for ten patients presenting with
SMA at a single center. Chiefly, this series demonstrates the need for
urgent surgical repair to improve mitral regurgitation and overall
prognosis.

Submitral aneurysms are an extremely rare pathology typically found in
young patients\textsuperscript{1-3}. While they were originally
described in Western and Southern African populations, SMAs have been
identified in patients across a variety of races and
ethnicities\textsuperscript{4}. In contrast to posterior left
ventricular aneurysms, which often occur due to ischemic etiology,
submitral aneurysms are believed to be largely congenital in
nature\textsuperscript{1,4--7}. The pathology likely stems from a
weakening of the fibrous tissue of the posterior mitral annulus, which
creates an outpouching between the annulus and the left ventricular
endocardium that restricts the posterior mitral
leaflet\textsuperscript{6}. Nayak et al. suggest the presence of a
submitral curtain, a fibrous separation between the fibrous annulus and
the left ventricular musculature, further predisposes patients to
developing SMA\textsuperscript{8}. As a consequence of dysfunctional
posterior leaflet motion and coaptation, patients with SMA often present
with severe mitral regurgitation. Additionally, patients with aneurysms
that compress the left circumflex artery may present with symptoms
resulting from coronary compression\textsuperscript{9}.

Acquired submitral aneurysms have also been described; prior case
reports have outlined SMAs secondary to Takayasu's arteritis, rheumatic
heart disease, and cardiac ischemia\textsuperscript{6,10,11}. While
transmural infarction typically causes apical aneurysm, ischemia-induced
SMAs have been documented in prior literature and in three patients in
the authors' series\textsuperscript{1,7}. Infectious agents such as
human immunodeficiency virus (HIV) and tuberculosis have also been
proposed as etiologies of SMA, as inflammation is suspected to
contribute to the pathogenesis and may exacerbate the congenital
pathology of SMA. However, it is still uncertain whether these
infectious etiologies are causative or a coincidental reflection of the
diseases endemic to the demographic in which SMA is typically
found\textsuperscript{4,12}.

SMA are classified based on the extent of posterior annular involvement:
Type I SMA have a single localized neck, Type II SMA have multiple
necks, and Type III SMA involve the entirety of the posterior fibrous
annulus\textsuperscript{4}. Clinically, the aneurysms are often
asymptomatic and incidentally discovered on
echocardiography\textsuperscript{5}. However, symptomatic patients often
present with severe mitral regurgitation and require surgery. Moreover,
coronary compression and risk of aneurysmal rupture prompt surgical
management in many cases\textsuperscript{9,13}. This stands in clear
contrast to the management of classical ventricular aneurysm, for which
surgery is not immediately indicated\textsuperscript{14}. As evidenced
by previous cases, SMA can rapidly progress to cardiogenic shock without
swift intervention\textsuperscript{6}. Furthermore, failure to identify
multiple aneurysmal necks during surgery has been suggested as an
impediment to surgical intervention\textsuperscript{4}. The importance
of surgical intervention was emphasized in this series presented by
Aggarwal et al., as two of the three patients who refused surgery died
within three months\textsuperscript{1}.

The classical approach to SMA repair is extensively detailed in the
literature dating back to 1963 by Drs. Schrire and
Barnard\textsuperscript{3}. Typically performed via median sternotomy,
SMA repair also has been reported through left-sided
thoracotomy\textsuperscript{15}. During the operation, consideration
must be given to the location of the left circumflex artery, as
aneurysmal location may overlap. Coronary angiography can be applied to
visualize both the location of the left circumflex and the direction of
the aneurysmal growth\textsuperscript{15}.

Two techniques have largely been described as the means to repairing an
SMA: the intracardiac and extracardiac approaches. The intracardiac
approach described by Dr. Antunes includes left atriotomy anterior to
the pulmonary veins and posterior to the vena cavae, similar to the
approach of a classical open mitral valve repair\textsuperscript{3}. In
the series reported by Dr. Antunes, the posterior leaflet was retracted
and its free edge was everted in order to reveal submitral dilatation.
Subsequent incision 20-25 mm from the free edge of the posterior leaflet
was then performed to enable closure from inside the aneurysm. Traction
sutures can be placed at the aneurysmal neck to close the dilatation and
reattach the posterior leaflet when necessary. Repair can also be
facilitated through the use of a Dacron patch and excess tissue
excision\textsuperscript{16}. The extracardiac approach is performed by
opening the epicardial side of the aneurysmal wall and exposing the
aneurysm anterior to the atrio-ventricular groove by retracting and
twisting the heart counterclockwise\textsuperscript{4}. However,
difficulties in exposing the mitral annulus have been noted with this
approach.

With the poor prognosis demonstrated by this series (40\% mortality at
one-year follow-up), astute attention to management is imperative. While
the study's sample is not of large power, it appears essential to
address surgical repair in patients with SMA; surgical intervention in
this series demonstrated 100\% survival one year post-diagnosis.
Moreover, the three patients who received mitral valve replacement
experienced sustained improvement of mitral regurgitation and were doing
well in one-year follow-up. As such, this data suggests a pattern of
improvement following surgical intervention and reinforces a poor
prognosis for SMA when surgery is refused. However, the lack of
long-term follow-up data on complications and outcomes for patients with
SMA exposes an existing gap in the literature.

While this series is one of the largest of its kind for follow-up
explicitly involving SMA, we urge more in-depth investigation of the
risk factors, comorbidities, and outcomes of SMA. Additionally, the
approach to management and long-term follow-up of SMA is underreported,
and the field would benefit from further investigation in this realm.
Creative approaches to gain insight into anatomic variability have been
reported, including the use of 3D printing to inform aneurysmal
closure\textsuperscript{17}. We anticipate less invasive approaches to
SMA repair have been attempted, including the use of robotics, however
no such characterizations exist in the literature. As technology
progresses and allows for stronger visualization with less invasion, we
expect to see an increase in the use of minimally invasive techniques to
provide superior results and less associated postoperative adverse
effects. With more extensive investigation into the long-term outcomes
of various approaches to management of SMA, we believe the prognosis of
this rare presentation can be improved.

\textbf{Abbreviations} : SMA: submitral aneurysm; HIV: human
immunodeficiency virus

\textbf{References}

1. Aggarwal P, Shrivastava A, Kuber D, Nath RK, Sinha SK, Kumar T, Raj
A, Pandit B. Outcome of Sub-mitral aneurysm. Journal of Cardiac Surgery.
2022.

2. Abrahams DG, Barton CJ, Cockshott WP, Edington GM, Weaver EJ. Annular
subvalvular left ventricular aneurysms. Q J Med. 1962;31:345-360.

3. de Antunes M. Submitral left ventricular aneurysms. J Thorac
Cardiovasc Surg. 1987; 94:241-5.

4. Du Toit H. Left ventricular sub-valvar mitral aneurysms. Interact
Cardiovasc Thorac Surg. 2003;2(4):547-551.
doi:10.1016/S1569-9293(03)00141-5

5. Corrado G. Submitral congenital left ventricular aneurysm: you
recognize only what you know. Journal of Cardiovascular Echography.
2017;27(1):29. doi:10.4103/2211-4122.199057

6. Barnawi A, Al Otaibi A, Soliman A, Al Rifae M, Al Baradie A, Ghazal
S. A Case of Submitral Aneurysm Presenting with Severe Mitral
Regurgitation and Shock in an African Male Patient with Rheumatic Heart
Disease. CASE (Phila). 2021;5(4):224-226. doi:10.1016/j.case.2021.04.001

7. Prasad K, Gupta H, Sihag BK, et al. Submitral aneurysm of varied
aetiologies: a case series. Eur Heart J Case Rep. 2021;5(2):ytab066.
doi:10.1093/ehjcr/ytab066

8. Nayak VM, Victor S. Sub-mitral membranous curtain: A potential
anatomical basis for congenital Sub-mitral aneurysms. Indian J Thorac
Cardiovasc Surg. 2006;22(4):205-211. doi:10.1007/s12055-006-0003-4

9. Thangasami S, Sahoo SS, Chandrasekaran A, Raval P, Shaniswara P.
Large sub-mitral aneurysm compressing the left circumflex coronary
artery presenting with atypical chest pain - Rare presentation. J
Cardiol Cases. 2020;21(5):193-196. doi:10.1016/j.jccase.2020.02.008

10. Rose AG, Folb J, Sinclair-Smith CC, Schneider JW. Idiopathic annular
submitral aneurysm associated with Takayasu's aortitis. A report of two
cases. Arch Pathol Lab Med. 1995;119(9):831-835.

11. Baruteau A-E, Martins RP, Boulmier D, et al. Acquired left
ventricular submitral aneurysms in the course of Takayasu arteritis in a
child. Congenit Heart Dis. 2012;7(1):76-79.
doi:10.1111/j.1747-0803.2011.00537.x

12. Chesler E, Joffe N, Schamroth L, Meyers A. Annular subvalvular left
ventricular aneurysms in the south african bantu. Circulation.
1965;32:43-51. doi:10.1161/01.cir.32.1.43

13. Raghuram P, Sivakumar K, Sheriff EA. Acquired submitral aneurysms
may be associated with mitral paravalvular leaks. Asian Cardiovasc
Thorac Ann. 2021;29(8):822-825. doi:10.1177/02184923211006310

14. Ruzza A, Czer LSC, Arabia F, et al. Left ventricular reconstruction
for postinfarction left ventricular aneurysm: review of surgical
techniques. Tex Heart Inst J. 2017;44(5):326-335.
doi:10.14503/THIJ-16-6068

15. Purushotham S, Manohar SRK, Sivasubramaniam S, Neelakandhan KS.
Submitral left ventricular aneurysm: the location of the circumflex
coronary artery in relation to the aneurysm influences the surgical
approach and outcome. J Thorac Cardiovasc Surg. 2005;129(5):1175-1177.
doi:10.1016/j.jtcvs.2004.08.044

16. Baruah DK, Kumar PVN, Reddy GSP, Babu VR. Submitral aneurysm of the
left ventricle. Indian Heart J. 2012;64(1):77-79.
doi:10.1016/S0019-4832(12)60015-7

17. Shetty I, Lachma RN, Manohar P, Rao PSM. 3D printing guided closure
of submitral aneurysm-an interesting case. Indian J Thorac Cardiovasc
Surg. 2020;36(5):506-508. doi:10.1007/s12055-020-00973-6

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