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Feasibility of Transvenous Coronary Sinus Lead Implantation in Congenitally Corrected Transposition of the Great Arteries
Canadian Journal of Cardiology 30 (2014) 248.e11 www.onlinecjc.ca
Letters to the Editor Feasibility of Transvenous Coronary Sinus Lead Implantation in Congenitally Corrected Transposition of the Great Arteries We read with interest the article titled, “Electrophysiologic Considerations in Congenital Heart Disease and Their Relationship to Heart Failure” by Escudero et al., in the July 2013 of the Canadian Journal of Cardiology.1 The review is comprehensive and has important educational value. Nonetheless, we feel it important to comment on what we believe is an erroneous statement relating to the role of cardiac resynchronization therapy (CRT) in patients with congenitally corrected transposition of the great arteries (CCTGA). The authors’ assertion that “In patients with CCTGA, the coronary sinus courses along the AV valve of the subpulmonary ventricle such that epicardial access is required to pace the systemic ventricle” is most likely a typographical error, because it is well known that the coronary sinus is embryologically a left atrial structure, courses behind the left atrium,2,3 and opens into the right atrium.2,4 Hence, in CCTGA, the coronary sinus ostium is located in the right atrium and its path runs adjacent to the subaortic right ventricle, which it predominantly drains.2,3 This coronary sinus anatomy makes it suitable for transvenous placement of a lead intended to pace the systemic (subaortic) right ventricle; thus, it is certainly possible to establish CRT in a patient with CCTGA without recourse to epicardial leads.3 It remains true that inadequately sized midlateral subaortic right ventricular venous tributaries may complicate the procedure,4 so as suggested by Diller et al.,2 we find pre-CRT imaging of the
coronary venous system invaluable in this patient group to identify anatomical variations. We thank the editor for the opportunity to bring this very important matter to the reader’s attention. Krishnakumar Nair, MD [email protected] Erwin Oechslin, MD Mohit Singla, MD S. Lucy Roche, MBChB Disclosures The authors have no conflicts of interest to disclose. References 1. Escudero C, Khairy P, Sanatani S. Electrophysiologic considerations in congenital heart disease and their relationship to heart failure. Can J Cardiol 2013;29:821-9. 2. Diller GP, Okonko D, Uebing A, Ho SY, Gatzoulis MA. Cardiac resynchronization ventricle: analysis of feasibility and review of early experience. Europace 2006;8:267-72. 3. Malecka B, Bednarek J, Tomkiewicz-Pajak L, et al. Resynchronization therapy transvenous approach in dextrocardia and congenitally corrected transposition of great arteries. Cardiol J 2010;17:503-8. 4. Bottega NA, Kapa S, Edwards WD, et al. The cardiac veins in congenitally corrected transposition of the great arteries: delivery options for cardiac devices. Heart Rhythm 2009;6:1450-6.
0828-282X/$ - see front matter Ó 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.cjca.2013.10.004
Letters to the Editor Feasibility of Transvenous Coronary Sinus Lead Implantation in Congenitally Corrected Transposition of the Great Arteries We read with interest the article titled, “Electrophysiologic Considerations in Congenital Heart Disease and Their Relationship to Heart Failure” by Escudero et al., in the July 2013 of the Canadian Journal of Cardiology.1 The review is comprehensive and has important educational value. Nonetheless, we feel it important to comment on what we believe is an erroneous statement relating to the role of cardiac resynchronization therapy (CRT) in patients with congenitally corrected transposition of the great arteries (CCTGA). The authors’ assertion that “In patients with CCTGA, the coronary sinus courses along the AV valve of the subpulmonary ventricle such that epicardial access is required to pace the systemic ventricle” is most likely a typographical error, because it is well known that the coronary sinus is embryologically a left atrial structure, courses behind the left atrium,2,3 and opens into the right atrium.2,4 Hence, in CCTGA, the coronary sinus ostium is located in the right atrium and its path runs adjacent to the subaortic right ventricle, which it predominantly drains.2,3 This coronary sinus anatomy makes it suitable for transvenous placement of a lead intended to pace the systemic (subaortic) right ventricle; thus, it is certainly possible to establish CRT in a patient with CCTGA without recourse to epicardial leads.3 It remains true that inadequately sized midlateral subaortic right ventricular venous tributaries may complicate the procedure,4 so as suggested by Diller et al.,2 we find pre-CRT imaging of the
coronary venous system invaluable in this patient group to identify anatomical variations. We thank the editor for the opportunity to bring this very important matter to the reader’s attention. Krishnakumar Nair, MD [email protected] Erwin Oechslin, MD Mohit Singla, MD S. Lucy Roche, MBChB Disclosures The authors have no conflicts of interest to disclose. References 1. Escudero C, Khairy P, Sanatani S. Electrophysiologic considerations in congenital heart disease and their relationship to heart failure. Can J Cardiol 2013;29:821-9. 2. Diller GP, Okonko D, Uebing A, Ho SY, Gatzoulis MA. Cardiac resynchronization ventricle: analysis of feasibility and review of early experience. Europace 2006;8:267-72. 3. Malecka B, Bednarek J, Tomkiewicz-Pajak L, et al. Resynchronization therapy transvenous approach in dextrocardia and congenitally corrected transposition of great arteries. Cardiol J 2010;17:503-8. 4. Bottega NA, Kapa S, Edwards WD, et al. The cardiac veins in congenitally corrected transposition of the great arteries: delivery options for cardiac devices. Heart Rhythm 2009;6:1450-6.
0828-282X/$ - see front matter Ó 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.cjca.2013.10.004