A 31-year-old female undergoes preconception cardiac evaluation. Medical history is significant for tetralogy of Fallot with a palliative right subclavian artery to pulmonary artery (Blalock-Taussig) shunt in infancy. Which of the following is the most important consideration regarding her pregnancy planning?
a) Assessing right ventricular function
b) Evaluating for residual shunt or stenosis
c) Monitoring for cyanosis and hypoxemia
d) Assessing for pulmonary hypertension