Composite risk index to predict adverse cardiac outcomes in pregnant women with congenital heart disease

WOMEN WITH CONGENITAL HEART DISEASE DAVID W. OUYANG, PAUL KHAIRY, SUSAN FERNANDES, KATHERINE ECONOMY, AVIVA LEE-PARRITZ, MICHAEL LANDZBERG, Brigham and Women’s Hospital, Maternal Fetal Medicine, Boston, Massachusetts, Children’s Hospital, Boston, Massachusetts, Boston Medical Center, Maternal Fetal Medicine, Boston, Massachusetts OBJECTIVE: A composite risk index to predict maternal cardiac complications has been proposed as a contemporary approach to risk stratify pregnant women with heart disease. We sought to independently validate this risk index in women with congenital heart disease. STUDY DESIGN: We conducted a retrospective, single center, cohort study examining maternal outcomes in women with congenital heart disease who delivered between 1998-2004. Patients received 1 point for each of the following predictors: Previous cardiac event (h/o CHF/stroke/arrhythmia); baseline NYHA class >2 or central cyanosis; LV outflow tract obstruction; and LVEF ! 40%. The cardiac event rates were stratified by the risk index scoring system and compared to the predicted rate. The predicted rate of a primary cardiac event in pregnancies with 0, 1, and R2 points is 5%, 27% and 75% respectively. Primary events were defined as CHF; sustained arrhythmia; stroke; cardiac arrest; and cardiac death. RESULTS: 53 patients were studied who completed a total of 83 pregnancies. All patients had a baseline NYHA class %2. Six patients had a h/o CHF, eleven had a h/o arrhythmia and one patient had a h/o stroke. No patients had central cyanosis or LVEF !40%. A primary cardiac event occurred in 15 pregnancies, all of which were cases of CHF (n = 9) and arrhythmia (n = 8). In two pregnancies, both CHF and arrhythmia were observed. The predicted rate of a primary cardiac event based on the composite risk index was similar to the observed rate (Table). CONCLUSION: This study represents the largest single institution experience evaluating cardiac outcomes in pregnant women with congenital heart disease. It provides the first independent validation of the risk index scoring system proposed to predict adverse cardiac events in pregnant women with heart disease.