Tricky Diagnosis: An Aberrant Mitral Valve Chord

Heart Defects, Congenital Atrial Septum; Staphylococcus Aureus; Mitral Valve Insufficiency; Endocarditis Bacterial; Diagnostic Imaging/methods

Case

We present the case of a 52-year-old man with hepatitis C and a history of intravenous drug abuse, admitted to the infectology department with spondylodiscitis and psoas muscle abscess. Staphylococcus aureus was isolated from blood, urine, and spinal fluid cultures, and the transthoracic echocardiogram was negative for vegetation, abscess, or fistula. The transesophageal echocardiogram (TEE) showed a filamentous and mobile structure attached to the atrial surface of the mitral valve (MV), and a diagnosis of infective endocarditis was presumed. Seven days later, the patient was referred to our tertiary institution for a detailed TEE. In 2D images, we found a thin, well-delineated strand connecting the interatrial septum (IAS) to the tip of the anterior mitral leaflet without significant regurgitation ( Figure 1A , supplementary video 1). 3D imaging confirmed the presence of an anomalous chord connecting the A2 scallop of MV to the middle of the interatrial septum ( Figure 1B , supplementary video 2). There was no evidence of infective endocarditis, and this strand was found to be compatible with an anomalous left atrial MV chord.

Figure 1
– 2D transesophageal echocardiogram images showing a fine, well-delineated structure (yellow arrow) originating from the interatrial septum to the tip of the anterior leaflet of the mitral valve. There is no significant regurgitation on the color Doppler (right).

Figure 2
– 3D transesophageal echocardiogram images confirm the presence of an anomalous chord connecting the A3 segment of the mitral valve (MV) to the middle region of the interatrial septum (IAS).

Anomalous insertion of the left atrial (LA) mitral valve (MV) chord is a rare congenital anomaly with unclear clinical relevance. Some reports highlight this anomaly as a cause of significant mitral regurgitation where surgery may be indicated.¹ , ² Additionally, complex mitral valve endocarditis involving an anomalous LA MV chord has been recorde.³ However, in patients without significant mitral regurgitation or active infection, adequate recognition of this anomaly is essential to avoid unnecessary treatment or incorrect diagnosis.⁴ , ⁵

Referências

• ¹
  Brown A, Fung K, Ma G, Ripley DP. Image of the Quarter: Clinical Aberrant atrial insertion of the mitral valve chord. J R Coll Physicians Edinb. 2019; 49(2):139–40. doi: 10.4997/JRCPE.2019.212
• ²
  Khan H, Chaubey S, Kenny C, MacCarthy P, Wendler O. A rare case of an aberrant anterior mitral valve chord resulting in severe mitral regurgitation. J Surg Case Reports. 2011; (5):1. 10.1093/jscr/2011.5.1
• ³
  Chhabra SK, Bogar LJ, Decaro MV, Cohen IS. Complex mitral valve endocarditis involving a left atrial false tendon. J Am Coll Cardiol. 2012; 60(22):2330. doi: 10.1016/j.jacc.2012.03.084
• ⁴
  Floria M, Gerard M, Marchandise B, Schroeder E. Aberrantly inserted chordae tendineae without significant mitral regurgitation. J Clin Ultrasound. 2014; (42):57–8. doi: 10.1002/jcu.22001
• ⁵
  Bertrand PB, Churchill TW, Passeri JJ. A Left Atrial Mitral Valve Chord. JACC Case Reports. 2020; (2):526-7. doi: 10.1016/j.jaccas.2019.11.079

• Study association
  This study is not associated with any thesis or dissertation work
• Ethics approval and consent to participate
  This article does not contain any studies with human participants or animals performed by any of the authors.

• Sources of funding: There were no external funding sources for this study.

Publication Dates

• Publication in this collection
  10 Mar 2023
• Date of issue
  2023

History

• Received
  08 Aug 2022
• Reviewed
  28 Oct 2022
• Accepted
  14 Dec 2022