ABC | Volume 114, Nº5, May 2020

Statement Brazilian Cardiology Society Statement for Management of Pregnancy and Family Planning in Women with Heart Disease – 2020 Arq Bras Cardiol. 2020; 114(5):849-942 3.6.4.1. Aortic Dissection and Rupture Gestation increases a woman’s susceptibility to dissection and rupture of the aorta. In the general population, the incidence of aortic dissection is 6 cases per 100,000 individuals yearly; nevertheless, during pregnancy, the occurrence increases 100-fold, to approximately 0.6%.For this reason, diagnosis of aortic dissection should be considered in all patients with chest pain during pregnancy. It occurs more frequently during the last trimester (50%) or the initial postpartum period (33%). 52 Marfan syndrome is the most common conjunctive tissue disease, caused by a mutation in the FBN-1 gene, which codifies the inherited glycoprotein fibrillin in an autosomal dominant pattern. 254 Average increase in aortic diameter growth during gestation in patients with Marfan syndrome is 0.3 mm/month, while in the general population with Marfan syndrome, it is 0.38 mm/year. 254 This increased rate of aortic dilatation decreases after delivery, but it remains higher than the pre-gestational rate. 253 Diagnosis includes history, physical examination, echo, and magnetic resonance of the aorta. Thoracic aortic angiography complements investigation when there is strong suspicion of dissection based on previous examinations. One of the most important factors for determining the risk of dissection of the aorta is maximum diameter (< 40 mm, 1% risk of dissection; > 40 mm, 10% risk of dissection). 255 Pregnancy is generally contraindicated if the ascending aorta diameter is greater than 40 mm in patients with family history of dissection or sudden death, even though the exact dimension is still a question of debate. 254 There seems to be a low incidence of dissection if aorta diameter is lower than 4.5 cm; pregnancy, however, increases the late risk of aortic complications. 52,254,256 One important consideration is body surface area, especially in small women. Aorta diameter index higher than 27 mm/m 2 is associated with a high risk of dissection, and prophylactic replacement of the aortic root should be considered. 52 It is also necessary to evaluate associated cardiovascular problems, including the possibility of aortic regurgitation and mitral valve prolapse with associated regurgitation. Beta-blockers have been shown to increase aortic distensibility and reduce pulse wave velocity and reducing the rate of complications such as regurgitation, dissection, and congestive HF. A 20% decrease in resting heart rate is considered to be the objective of treatment. 257 Periodic echocardiographic monitoring is recommended every 6 to 8 weeks to monitor the size of the mother’s aortic root; the interval depends on initial echocardiographic findings. 254 The preferred route of delivery is cesarean in patients with aortic dilatation > 45 mm, and delivery should take place in a tertiary center where there is an experienced surgery team. In patients with diameters < 45 mm, with no previous events, delivery may be vaginal, with early analgesia and relief forceps. Preconception counseling requires determination of the underlying disease, genetic evaluation, and aortic dilatation correction in accordance withdiameter thresholds (Table 26). Ehlers-Danlos syndrome type IV occurs with severe vascular complications, with characteristics of autosomal dominant inheritance and 50% risk of transmission to offspring. Maternal mortality is significant, and it is related to uterine rupture and dissection of the great arteries and veins. Pregnancy is, therefore, considered a high-risk situation, and it is not advised (WHO risk IV); in this manner, when contemplating pregnancy, these women should be advised in a shared decision-making process. 52 In vascular Ehlers-Danlos syndrome, also a rare severe conjunctive tissue disease, characterized by fragile vascular tissue, vascular rupture has been related during pregnancy in up to 50% of cases, with mortality rates between 5% and 50%. Gestation, in these cases, is also associated with premature rupture of fetal membranes, spontaneous abortion, and prematurity. 52 Turner syndrome 256 is themost common sexual chromosome abnormality inwomen, and it occurs in 1 of every 1,500 to 2,500 female live births. Chromosome constitution may be absence of an X chromosome (karyotype 45,X) or chromosome mosaicism (karyotype 45,X/46,XX), as well as other structural anomalies of chromosome X. 256 Turner syndrome is associated with increased risk of heart disease, aortic dilatation, hypertension, diabetes mellitus, and atherosclerotic disease events. 256 Dissection of the aorta in patients with Turner syndrome is estimated to be 36 in 100,000 cases, but it is 6 times more common in younger age ranges than in the general population. 52 Risk factors include dilatation of the aorta, bicuspid aortic valve, and coarctation of the aorta. 52 Pregnancy should be avoided when aortic size index is > 25 mm/m 2 . Furthermore, after aortic root surgery, patients continue to be at a risk of a type B dissection. Although spontaneous pregnancy may occur in patients with Turner mosaic (0.5% to 10%), it is more common with assisted fertility. For this reason, cardiovascular evaluation is recommended before beginning fertility treatment. Furthermore, good blood pressure and diabetes control during pregnancy is mandatory for all patients with Turner syndrome. 52 Loeys-Dietz syndrome 258 is an autosomal dominant condition. It was described for the first time in 2005, and it is associated with formation or dissection of an aneurysm in the aorta or in other arteries, generally at a young age. 258 It has been identified in individuals referred for investigation for Marfan syndrome 257 or vascular Ehlers-Danlos syndrome who did not present the classical characteristics of these conditions, but rather others characteristics, including general arterial tortuosity, hypertelorism, bifid/broad uvula, or cleft palate. 257 Table 26 – Aorta diameter thresholds and indication for intervention in patients considering pregnancy 257 Underlying disease Ascending aorta diameter Marfan syndrome 45 mm Loeys-Dietz syndrome 40 – 45 mm Ehlers-Danlos syndrome type IV Pregnancy contraindicated Bicuspid valve 50 mm Turner syndrome 27 mm/m 2 892