Since percutaneous balloon pulmonary valvuloplasty (BPV) for pulmonary valve stenosis (PS) was first successfully performed by Rubio-Alverez and Limon-Lason1 using a ureteral catheter in 1950s, it has become the standard of care for treatment of isolated PS over surgical valvotomy.2,3 In 2000, based on these experiences, the percutaneous pulmonary valve implantation (PPVI) was first performed by Bonhoeffer et al4 in a patient with a dysfunctional of right ventricle–to–pulmonary artery conduit. In 2010, the Melody valve (Medtronic, Minneapolis, MN) became commercially available in the United States under a humanitarian device exemption protocol and, more recently, was awarded postmarket approval by the US Food and Drug Administration. Since then, PPVI has been performed in over 4500 patients in more than 30 countries worldwide. In this chapter, we will review BPV and PPVI with particular focus on the indication, technical aspect, clinical outcomes, and potential complications.
BALLOON PULMONARY VALVULOPLASTY
Patient Selection and Clinical Indication
Isolated PS is a relatively common disorder, accounting for approximately 10% of all congenital heart defects,3,5 and it varies in regard to severity of obstruction to the pulmonary orifice size, leaflet morphology (eg, dome-shaped, unicommissural, bicuspid, or dysplastic tricuspid valve), and annulus (eg, hypoplastic or enlarged annulus).6 Other congenital cardiac defects that may be associated with PS include atrial septal defect, ventricular septal defect, tetralogy of Fallot, transposition of the great arteries, double-outlet right ventricle, and ventricular inversion.7 Significant obstruction may lead to an inability to augment pulmonary blood flow during exertion, resulting in exercise-induced fatigue, syncope, or chest pain. Physical examination reveals a systolic ejection murmur with maximal intensity at the left upper sternal border, and transthoracic echocardiography is key to determining the severity and morphologic diagnosis. Once a severe PS is diagnosed, cardiac catheterization is performed in order to provide appropriate therapy.
Given the relative low risk and high likelihood of a long-standing good result, the generally accepted indication of BPV is more than moderate degree of PS (echocardiographic peak instantaneous pressure gradients ≥50 mm Hg or mean Doppler pressure gradients ≥30 mm Hg for symptomatic patients and peak Doppler pressure gradients ≥60 mm Hg or mean pressure gradients ≥40 mm Hg for asymptomatic patients) with less than moderate pulmonary valve regurgitation.8 BPV provides an immediate reduction of pulmonary valvular gradients and modest increase of pulmonary pressure and cardiac index. Improvement in right ventricular dysfunction frequently results in reduction of tricuspid regurgitation and right-to-left shunt if it exists.9 Patients with mild (gradient <30 mm Hg) stenosis are contraindicated for intervention, as natural history studies have demonstrated the benign natural history of mild PS at follow-up.10 Even in the asymptomatic patient, severe PS should be treated to prevent myocardial damage associated with long-term right ventricular pressure overload.11,12 Exercise testing may induce abnormal hemodynamic response due to low cardiac output in ...