Background Congenital heart disease presents unique challenges in pregnant patients due to the physiological changes of pregnancy. This case discusses a pregnant patient with incomplete D- loop miso/dextrocardia with situs solitus and Shone's complex who presented after a cardiac arrest.

Case Presentation A 33-year-old pregnant female with a past medical history of congenital heart disease incomplete D-loop, meso/dextrocardia with situs solitus, and Shone's complex), paroxysmal atrial fibrillation, and schizophrenia was brought in following PEA cardiac arrest with ROSC achieved in the field by EMS personnel. Cardiac workup was largely benign, with no signs of ischemia on EKG and initially elevated but quickly downtrending troponin levels. Transthoracic echocardiogram was stable from baseline and showed a reduced left ventricular ejection fraction of 25-30% with global hypokinesis of the left ventricle, bioprosthetic aortic valve, congenital transposition of the great vessels, and perimembranous VSD. ICU course was complicated by refractory status epilepticus secondary to anoxic brain injury, necessitating a Cesarean section at 34 weeks, to allow for the introduction of additional anti-epileptic drugs (AEDs). After a lengthy hospital stay of 2 months, she was discharged to an LTAC.

Discussion The management of adult individuals with congenital cardiac abnormalities is quite difficult as they are quite rare, and the variant anatomy may respond atypically to classical treatments. This case was complicated by pregnancy and the number of congenital cardiac conditions which are discussed next. An incomplete d-loop which refers to how the normal inflow portion of the right ventricle lies to the right of the left ventricle but in this patient, only partially does. Dextrocardia is the normal position of the heart but this patient instead partially suffered from a midline heart, or mesocardia. To qualify for Shone’s syndrome, at least 3 of 8 criteria must be satisfied: this patient had a bicuspid aortic valve, hypoplastic left ventricle, small aortic arch, and supramitral ring. While no clear etiology for the cardiac arrest was determined, it was presumed that heavy alcohol use with pregnancy placed too much of a strain on heart with these many abnormalities. Pregnancy also played a role in management of seizures as certain AEDs are extremely teratogenic and initially limited the 4 AED regiment. The case underscores the importance of a multidisciplinary approach involving numerous specialties and tailored management plans for patients with extremely complicated medical histories.