The aortic root usually measures approximately 2 cm, and during normal pregnancy, it expands slightly (Easterling, 1991). With Marfan syndrome, aortic root repair is recommended at diameters of 4.0 to 4.5 cm (Smok, 2014). The guidelines of the American College of Cardiology, the American Heart Association, and the merican Association of horacic Surgeons advise prophylactic aortic repair in women considering pregnancy if the diameter of the ascending aorta exceeds 4 cm (Hiratzka, 2010). The guidelines of the European Society of Cardiology (2011) advise repair of the aorta at diameters :::4.5 cm. Because shorter patients have dissection at a smaller diameter, surgical repair is also considered using a formula indexed to height (Bradley, 2014; Smok, 2014).
For pregnant women with known thoracic aortic root or ascending aortic dilation, monthly or bimonthly echocardiographic measurements of the ascending aortic dimensions are recommended to detect expansion (Hiratzka, 2010). Prophylactic 3-blocking agents have become standard for pregnant women with �1arfan syndrome because they reduce hemodynamic stress on the ascending aorta and slow the dilation rate (Simpson, 2012). Ideally, pregnant women with aortic aneurysms are delivered at facilities in which cardiothoracic surgery is available. Vaginal delivery with regional analgesia and an assisted second stage seem safe for women with an aortic root diameter < 4 cm.
When the aortic root measures 4 to 5 cm or greater, elective cesarean delivery is recommended with consideration of postpartum replacement of the proximal aorta with a prosthetic graft (Simpson, 2012). Successful aortic root replacement during pregnancy has been described, but the surgery has also been associated with fetal hypoxic-ischemic encephalopathy (Mul, 1998; Seeburger, 2007). Several case reports describe emergency cesarean deliveries in women with acute type A dissections that were repaired successfully at the time of delivery (Guo, 2011; Haas, 2011; Papatsonis, 2009).
To evaluate obstetrical outcomes, investigators for one study of 63 women with Marfan syndrome analyzed their 142 pregnancies. Of 111 pregnancies progressing past 20 weeks' gestation, 15 percent delivered preterm, and 5 percent had preterm prematurely ruptured membranes (vleijboom, 2006). here were eight perinatal deaths, and half of the neonatal survivors were subsequently diagnosed with Marfan syndrome.
In this relatively rare lesion, the aorta is abnormally narrowed and is often accompanied by abnormalities of other large arteries. A fourth of afected patients have a bicuspid aortic valve, and another 10 percent have cerebral artery aneurysms. Other associated lesions are persistent ductus arteriosus, septal defects, and Turner syndrome. he collateral circulation arising above the coarctation remodels and expands, often strikingly, to cause localized erosion of rib margins by hypertrophied intercostal arteries. Typical indings include hypertension in the upper extremities but normal or reduced pressures in the lower extremities. Authors have described diagnosis during pregnancy using MR imaging (Sherer, 2002; Zwiers, 2006). Moreover, Jimenez-Juan and associates (2014) found that aortic diameter measured by �1R and the risk of adverse events during pregnancy were inversely correlated. Of note, no adverse outcomes occurred if the minimum diameter at the coarctation exceeded 15 mm.