ABSTRACT
Fetal balloon valvuloplasty Percutaneous ultrasound-guided direct punctures of the fetal heart have been employed for almost two decades in order to perform balloon valvuloplasties in fetuses with severe semilunar valve obstructions. These lesions result in pressure overload of the affected left or right ventricle. As a result, marked degrees of dilatation, hypertrophy, and endocardial fibroelastosis as well as growth failure of the obstructed ventricle and maldevelopment of associated cardiovascular structures can be observed. 29-32 These pathological changes can be so profound that, by the end of gestation, the affected side of the heart cannot participate in the normal postnatal biventricular circulation, and only palliative singleventricular surgical procedures can be offered. Doppler ultrasound examination of flow directions and/or patterns across the atrial septum, mitral valve, and aortic arch permits definition of which fetuses with severe aortic valve stenosis are most likely to develop dysfunctional left ventricles before term. 33,34 In these fetuses, percutaneous ultrasound-guided balloon valvuloplasties aim to restore growth and preservation of function of the affected left ventricle as well as the associated valvar and vascular structures ( Figure 35.3 ).
