Heterotaxia - Situs ambiguo, síndrome de Ivermark o síndrome de asplenia-poliesplenia

Abstract

El síndrome de heterotaxia es una patología poco común que se presenta debido a una disrupción durante el desarrollo embrionario de la orientación del eje, que puede llevar a múltiples alteraciones en la presencia, localización y función de órganos toracobdominales.

Atrial isomerism: A multidisciplinary perspective

“…Thus, prevalence can vary from region to region, with reports ranging from 2.1 to 12.3/1000 live births 4 , with an incidence of 6-8/1000 live births 5 . Among the múltiple congenital heart diseases, atrial isomerism stands out as a complex entity that is accompanied by a spectrum of cardiac and extra-cardiac malformations, and has been shown to be a rare entity, with a prevalence of 1 in every 10,000-20,000 live births, and an incidence of up to 4% among all cardiac malformations 6 .…”

“…By the end of the 3 rd week, during the period of cardiac cells differentiation, and starting from Hensen's node, the right and left structures development and lateralization take place 3,6 ; however, in patients with isomorphism, there are gene expression patterns, mainly involving the Nodal and Pitx2 genes, in addition to others such as NKX2-5, CRELD1, LEFTY2, ZIC3, and CRIPTC, which are associated with transforming growth factor-beta pathway components encoding, which when altered determines one of two entities: dextromorphism or levomorphism 3 .…”

“…Thus, both atria acquire a right morphology, with an absence of lateral structures such as the coronary sinus, for example. To this, other extracardiac malformations are added, such as bilaterally trilobed lungs, each one with a short bronchus, absence of spleen, and gut malrotation, among others 1,3,6,7 .…”

“…In addition, although less frequently than in dextromorphism, abnormal venous pulmonary drainage and the entire atrioventricular canal may be present and, in these cases, it is more likely for hearts with biventricular physiology to be found (Table 1). Extracardiac malformations that may occur are bilaterally bilobed lungs, each one with a long bronchus, and polysplenia, among others 1,3,[6][7][8] .…”

“…Initial evaluation, mainly at neonatal stage, is important within the context of fetal decision and counseling, as well as for early postnatal care 10 , which determines referral to different involved specialties. However, the recognition of certain signs and symptoms will lead us to suspicion of the clinical entity; for example, if there is evidence of cyanosis, which is the most common form of presentation, it can bring us closer to a probable dextromorphism, which sometimes results from an obstructed pulmonary drainage 1,2,6 , but association of other problems such as dyspnea and cardiac murmur could also make us suspect an associated pulmonary stenosis 1 . As regards levomorphism, symptoms usually occur at a later age, due to lower severity of associated lesions, such as mild obstructions at the level of the pulmonary artery, but they can have manifestations of chronicity such as tachypnea secondary to an already established heart failure or, on the other hand, be asymptomatic and start with problems associated with an extracardiac malformation 1,2,6,8 (Table 1).…”