Electro-Anatomical Approach to Membranous Septal Aneurysm: Potential as a Focus of Critical Ventricular Arrhythmias

Hajime Imura, Hiroshige Murata, Masami Ochi

Department of Cardiology, Nippon Medical School Hospital, Tokyo, Japan.
Department of Cardiovascular Surgery, Nippon Medical School Hospital, Tokyo, Japan.

DOI: 10.4236/ss.2013.412105                

Abstract

Membranous septal aneurysm (MSA) is a rare anomaly and known to cause ventricular tachycardia and atrioventricular block. However, underlying mechanisms have not been addressed in its long history. We report first 3-D electro-anatomical mapping of MSA during and three years following the surgery. An elderly patient underwent a surgery for MSA. In the mapping, we located the His bundle near MSA and observed delayed potentials around MSA. Our report showed that electrophysiological character of myocardium was changed around MSA and this change might be a reason for ventricular tachycardia and atrioventricular block. An ordinary surgery for MSA might not resolve this problem since we still observed delayed potentials three years after the surgery.

Keywords

Membranous Septal Aneurysm; Electro-Anatomical Mapping; Ventricular Tachycardia; Atrioventricular Block

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	R. I. Hamby, F. Raia and O. Apiado, “Aneurysm of the pars Membranacea. Report of Three Adults Cases and a Review of the Literature,” American Heart Journal, Vol. 79, No. 5, 1970, pp. 688-699. http://dx.doi.org/10.1016/0002-8703(70)90289-9
[2]	R. J. Clark and P. D. White, “Congenital Aneurismal Defect of the Membranous Portion of the Ventricular Septum Associated with Heart Block, Ventricular Flutter, Adams-Stroke Syndrome and Death,” Circulation, Vol. 5, No. 5, 1952, pp. 725-729.
[3]	A. Graffigna, G. Minzioni, L. Ressia, et al., “Surgical Ablation of Ventricular Tachycardia Secondary to Congenital Ventricular Septal Aneurysm,” The Annals of Thoracic Surgery, Vol. 57, No. 4, 1994, pp. 921-924. http://dx.doi.org/10.1016/0003-4975(94)90203-8
[4]	S. W. Jang, T. H. Rho and J. H. Kim, “Membranous Interventricular Septal Aneurysm Resulted in Complete Atrioventricular Block,” Heart, Vol. 96, No. 3, 2010, p. 244. http://dx.doi.org/10.1136/ hrt.2009.175588
[5]	W. G. Stevenson and K. Soejima, “Catheter Ablation for Ventricular Tachycardia,” Circulation, Vol. 115, No. 21, 2007, pp. 2750-2760. http://dx.doi.org/10.1161/CIRCULATIONAHA.106.655720
[6]	H. Furushima, M. Chinushi, K. Iijima, et al., “Ventricular Tachyarrythmia Associated with Hepertrophic Cardiomyopathy: Incidence, Prognosis, and Relation to Type of Hypertrophy,” Journal of Cardiovascular Electrophysiology, Vol. 21, No. 9, 2010, pp. 91-99. http://dx.doi.org/10.1111/j.1540-8167.2010.01769.x
[7]	B. A. Vidne, L. Chiariello, H. Wagner, et al., “Aneurysm of the Membranous Ventricular Septum. Surgical Consideration and Experience in 29 Cases,” The Journal of Thoracic and Cardiovascular Surgery, Vol. 71, No. 3, 1976, pp. 402-409.