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informed consent to publish this case report was obtained from the patient . a 31-year - old woman ( gravida 1 , para 0 ) with a gestational age of 29 weeks
the echocardiography and ct angiography revealed an acute aortic dissection ( stanford type a , debakey type 1 ) with severe aortic regurgitation .
her nt - probnp ( 885.9 pg / ml ) and d - dimer ( 0.79 g / ml ) levels were elevated .
the patient had no history of vascular events , hypertension , or previous vascular surgery .
she presented a clinical feature of suspected marfan syndrome and her family history included the sudden death of her father .
she was admitted to the intensive care unit for close hemodynamic monitoring of both the mother and the fetus .
her vital signs were within the normal range at admission ( systolic blood pressure : 120150 mmhg ; heart rate : 7080 beats / min ) .
the pediatrician reported that the fetus ' vital signs were stable and would be viable for extra - uterine life under adequate intensive care with surfactant therapy .
a cardiac anesthesiologist , thoracic surgeon , obstetrician and pediatrician discussed the treatment plan and concluded that a cesarean section followed by an ascending aorta and aortic arch replacement should be performed .
the thoracic surgeon and anesthesiologist decided not to perform a sternotomy prior to the cesarean section after weighing the risks and benefits of a sternotomy before the cesarean section . because the chest pain had developed two days prior to her visit to our er and the patient 's hemodynamic status was stable , the risk of spontaneous rupture during the cesarean section was not considered to be high .
we also considered that the hemodynamic response and surgical incision for a sternotomy could only increase the risk of aortic rupture , and a delayed cesarean section due to a sternotomy could jeopardize the fetus ' life .
instead , the thoracic surgical team was prepared for cpb in the operating room during the cesarean section .
the right radial and right femoral arterial blood pressure and central venous pressure were monitored .
labetalol 15 mg / h and nitroprusside 1 g / kg / min were infused before surgery .
a total intravenous anesthesia with propofol and remifentanil was performed with monitoring by transesophageal echocardiography ( tee ) and cerebral oximeter monitoring ( inovos5100b , troy , usa ) . a large bore central venous line ( 9 fr .
advanced venous access catheter , edwards lifesciences llc , irvine , ca , usa ) was accessed and connected with a rapid volume infuser ( level 1 , level 1 technologies , rockland , ma , usa ) .
the intraoperative tee revealed severe aortic regurgitation and intimal flap in the ascending aorta ( fig .
1 ) . cardiac output monitoring by a swan - ganz catheter was not performed so as not to delay the cesarean section and because a possible arrhythmia during the catheter insertion could result in hemodynamic instability . instead
, the left ventricular systolic function , the cardiac output and the degree of aortic regurgitation were monitored by tee during the cesarean section .
the hemodynamic goal during the cesarean section was to avoid an abrupt increase in blood pressure and to maintain an adequate preload and cardiac output .
considering the severe aortic regurgitation and dissection , the heart rate was controlled between 60 and 80/min .
a 1280 gm male baby was delivered with a 1 min apgar score of 2 and resuscitated with an endotracheal intubation .
the baby was admitted to the neonatal intensive care unit ( icu ) and treated with a surfactant . during the cesarean section ,
the hemodynamic parameters were kept stable with the inotropic support of dopamine ( 510 g / kg / min ) and norepinephrine ( 0.10.4 g / kg / min ) and a transfusion of packed red blood cell 2 units .
colloid 500 ml ( volulyte , fresenius kabi , bad homburg , germany ) was administered during the cesarean section .
after the cesarean section , an ascending aorta and total arch replacement , valve sparing aortic root replacement , aortic valvuloplasty with commissuroplasty , and a free graft from the aorta to the right coronary artery were performed under cpb . weaning from cpb was successful with dopamine ( 3 g / kg / min ) , dobutamine ( 3 g / kg / min ) , and nitroglycerine ( 1 g / kg / min ) .
a transfusion of prbc 2 units , cryoprecipitate 10 units , and platelet concentrate 16 units was guided by thromboelastography .
the patient was transferred to the cardiac icu and discharged without any complications on postoperative day # 6 .
aortic dissection during pregnancy is a rare condition that is life - threatening for both the pregnant woman and the baby , with a survival rate of only 20%30% .
it is often associated with a genetic or anatomic predisposition including marfan syndrome or bicuspid aortic valve .
marfan syndrome has been reported in up to 50% of the aortic dissections during pregnancy , with emergency surgery frequently performed at diagnosis .
the incidence of dissection during pregnancy in marfan syndrome patients was reported to be 3% .
it mostly occurs during the third trimester of pregnancy due to the hyperdynamic state and hormonal effects on the vasculature .
eighty percent of the dissections during pregnancy are a type a dissection , and 87.5% of these cases occur in the pre - partum period .
this results in a connective tissue disorder which often affects the cardiovascular system and may cause aortic root dilatation and aortic dissection .
aortic root dilatation and the rapidity of this dilatation were reported to be critical risk factors for aortic dissection during pregnancy .
aortic dissection in the peripartum period mostly occurs during the third trimester , which is a period of maximal hemodynamic stress .
estrogen was reported to inhibit collagen and elastin deposition in the aorta while progesterone promotes the deposition of noncollagen proteins in the aorta .
when these hormonal effects occur in a patient with marfan syndrome , aortic dissection could be initiated during pregnancy .
previous case series have reported the successful management of aortic dissection in pregnant women through a cesarean section with subsequent emergency aortic surgery for a stanford type a dissection   or by conservative management for a stanford type b dissection . in previous case series , the sternotomy was performed prior to the cesarean section to facilitate urgent cpb for possible hemodynamic instability during the cesarean section . however , in our case , the cesarean section was performed without a prior sternotomy . as mentioned previously , the onset of dissection was two days before the surgery , and the risk of rupture during the cesarean section was not considered to be high . in the case of an acute type b dissection , minimizing the surgical repair of the dissection
beta - blockers , calcium channel blockers and vasodilators such as sodium nitroprusside are commonly - used an anti - hypertensive agents .
vasodilators should not be used alone due to reflex tachycardia . for a type a dissection before the 30 week of gestation , aortic repair with the fetus in utero
although a high - flow , high pressure normothermic perfusion has been considered to be the safest for the fetus , there have been several case reports of successful hypothermia or deep hypothermic circulatory arrest during pregnancy before the 28 week of gestation . in our case ,
the cesarean section was performed before the aortic surgery , although before the 30 week of gestation . a decision based on the pediatrician 's opinion
was made that the gestational age was near 30 weeks , and the fetus was mature enough for extra - uterine life .
aortic dissection could occur during pregnancy in patients with marfan syndrome . to prevent this potential catastrophic event ,
preconception counseling should recommend prepregnancy elective aortic root replacement surgery in marfan syndrome patients with an aortic root enlargement .
elective replacement with valve - sparing procedures and a homograft can be performed with low morbidity and mortality in patients with marfan syndrome .
we performed general anesthesia for the cesarean section in our marfan syndrome patient with aortic dissection during pregnancy .
we chose general anesthesia because neuraxial anesthesia could produce a sympathetic block which would cause hemodynamic instability in this patient treated with a beta - blocker and vasodilator .
however , anesthesia for a cesarean section in marfan syndrome patients without aortic dissection would be different .
a previous article recommended performing a regional anesthesia for the cesarean section so as to avoid high blood pressure which could induce aortic dissection .
aortic dissection can occur during pregnancy in patients with marfan syndrome , mainly in the third trimester . if possible , surgical repair of the enlarged aortic root should be performed prepartum . however , if aortic dissection stanford type a occurs during pregnancy in a marfan syndrome patient , a cesarean section followed by aortic surgery is currently the best modality for treatment .
careful hemodynamic management during the cesarean section under general anesthesia with tee monitoring ensured the safety of the patient and baby without a prior sternotomy in our case .
aortic dissection during pregnancy is a devastating event for both the pregnant woman and the baby . 
 we report a case of acute aortic dissection ( stanford type a ) in a pregnant woman with marfan syndrome at the 29th week of gestation . 
 she underwent a cesarean section followed by an ascending aorta and total arch replacement with cardiopulmonary bypass , without a prior sternotomy . 
 the hemodynamic parameters were kept stable during the cesarean section by using inotropes and vasopressors under transesophageal echocardiography monitoring . 
 the newborn survived after endotracheal intubation and management in a neonatal intensive care unit .