The risk of major morbidity and mortality rises with the severity of ventricular dysfunction, and
there is an unpredictable risk of a permanent deterioration in ventricular function. Thus, women with
pre-existing moderate or severely impaired systemic ventricular function with an inability to increase
cardiac output on stress testing should be advised that pregnancy is associated with a high risk of
morbidity and mortality. If ventricular impairment is milder, then the main risk is of progressive
permanent decline in function.