Page 37 - Journal of Structural Heart Disease Volume 3, Issue 5

Key Words
Arterial duct patency • Stent implantation • Hypoplastic Left Heart Syndrome • Hybrid approach
Copyright © 2017 Science International Corp.
To the Editor,
A Newborn with hypoplastic left heart syndrome (HLHS) cannot survive without an open arterial duct and adequate inter-atrial communication. Prosta- glandin infusion is usually used to keep the duct pat- ent and balloon atrial septostomy, if needed, will be performed. Those with large inter-atrial communica- tion may survive the rst month of life, but the major- ity of them will gradually deteriorate and eventually die. The assumed change in pathophysiology leading to death is a reduction in pulmonary vascular resis- tance leading to lung congestion and less systemic perfusion ending with multi-organ failure.
Norwood cascade of surgical palliations for HLHS was rst performed in the early 1980s however during the last 20 years the concept of hybrid approach was introduced. This hybrid intervention encompasses balloon atrial septostomy, and surgical banding of pulmonary artery branches combined with translu- minal stenting of the arterial duct. The intervention needs to be performed in a special catheterization laboratory by both cardiac surgeons and interven-
tional cardiologist team (1). As a result of this com- plex operation, the right ventricle will pump blood to pulmonary and systemic circulation. The blood passes through arterial duct will, therefore, have a high pressure, with low oxygen partial pressure (PO2). Reported disadvantages of hybrid approach include the need for antiplatelet aggregation prophylaxis, the potential risk of reverse coarctation and possibly other complications while waiting for stage II (Glenn shunt and aortic arch reconstruction) palliation (2).
During the fetal life, the arterial duct is kept open by three mechanism: 1) the elevated intravascular pressure within the arterial duct due to constricted pulmonary vascular bed and high pulmonary vascu- lar resistance. 2) endogenous production of Prosta- glandin-E2 (PG-E2)produced by the duct endothelium. 3) The increased intracellular concentration of cAMP, nitric oxide production by fetal arterial duct and in- creased carbon monoxide production by endothelial and smooth muscle cell of the duct play an important role to keep the duct patent (3). After delivery, sever- al factors stimulate the duct constriction and closure, such as: increased PO2, reduced pressure within the duct lumen and decreased PG2 secretion and its re- ceptors.
Surgical banding of pulmonary artery branches, as part of the hybrid approach, would limit blood ow through the pulmonary artery branches and direct
* Corresponding Author:
Milad El-Segaier, MD, PhD
Pediatric Cardiology
King Fahad Medical City, King Salman Heart Center P. O. Box 59046, Riyadh 11525, Saudi Arabia
Tel. +966 11 2889999 (ext. 14677); Fax: +966 11 2889999 (ext. 12099); E-Mail: mail4milad@gmail.com
Letter-to-the-Editor
Journal of Structural Heart Disease, October 2017, Volume 3, Issue 5:163-164
DOI: http://dx.doi.org/10.12945/j.jshd.2017.044.17
Received: September 29, 2017 Accepted: October 5, 2017 Published online: October 2017
Do We Need to Stent Arterial Duct in Hybrid Approach for Hypoplastic Left Heart Syndrome?
Milad El-Segaier, MD, PhD1,2, Mohamed Omar Galal, MD, PhD, MBA3,4
1 Department of Paediatric Cardiology, King Fahad Medical City, KSHC, Riyadh, Saudi Arabia 2 Department of Paediatric Cardiology, Skåne University Hospital, Lund, Sweden
3 King Faisal Specialist Hospital & RC, Jeddah, Saudi Arabia
4 Kinderklinik, Essen University, Essen, Germany
Fax +1 203 785 3346
E-Mail: jshd@scienceinternational.org http://structuralheartdisease.org/
© 2017 Journal of Structural Heart Disease Published by Science International Corp. ISSN 2326-4004
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http://structuralheartdisease.org/