<unk>  is defined as the process in which a long-standing left-to-right cardiac shunt caused by a congenital heart defect (typically by a ventricular septal defect, atrial septal defect, or less commonly, patent ductus arteriosus) causes pulmonary hypertension and eventual reversal of the shunt into a cyanotic right-to-left shunt. Because of the advent of fetal screening with echocardiography early in life, the incidence of heart defects progressing to<unk> 's has decreased.<unk>  in a pregnant mother can cause serious complications, though successful delivery has been reported. Maternal mortality ranges from 30% to 60%, and may be attributed to fainting spells, blood clots forming in the veins and traveling to distant sites, hypovolemia, coughing up blood or preeclampsia. Most deaths occur either during or within the first weeks after delivery. Pregnant women with<unk>  syndrome should be hospitalized after the 20th week of pregnancy - or earlier if clinical deterioration occurs.
Eisenmenger's syndrome
Tetralogy of Fallot  Tetralogy of Fallot  1
Foville's syndrome
Lown–Ganong–Levine syndrome
Claude's syndrome
Saal Greenstein syndrome
Mietens syndrome
Löffler's syndrome