Right ventricular dysfunction and pulmonary valve replacement after correction of tetralogy of Fallot - Discussion

Background. Correction of tetralogy of Fallot often leads to pulmonary regurgitation, sometimes warranting pulmonary valve replacement, for which indications and timing to achieve optimal results are not yet clear. This retrospective study describes follow-up and reinterventions in our tetralogy of Fallot population. Methods. Review of all consecutive patients operated on for tetralogy of Fallot between 1977 and 2000 was conducted. Included are date and type of repair, Doppler echocardiography (two-dimensional echocardiography), electrocardiographs, reoperations, and physical condition. Results. Total repair was performed in 171 patients at a mean age 1.9 ± 2.5 years, follow-up time counted 9.6 ± 7.0 years. Right ventriculotomy was used in 92%, and transatrial ventricular septal defect closure was used in 8%; 74% received a transannular outflow patch. Twenty-year survival was 91%. Last follow-up electrocardiographs showed right bundle branch block in 67% and serious arrhythmias in 11%. Two-dimensional echocardiography demonstrated severe pulmonary insufficiency and dilated right ventricle in 31% and 38%, respectively, increasing with postrepair age (p < 0.001). Poor clinical condition (New York Heart Association class II+) and echocardiographic proof of right atrial dilatation (p = 0.012) and arrhythmias (p = 0.03) were significantly associated. Furthermore, the influence of residual hemodynamic lesions, such as a remaining ventricular septal defect or pulmonary stenosis, or right ventricular dilatation was important (p = 0.04). Reintervention was necessary in 32 patients (19%; 10-year freedom, 83%), including angioplasty for residual stenosis and pulmonary valve replacement. At a mean age of 9.2 years after correction, 14 patients received a homograft, and 2 patients received a heterograft. In 7 patients the right ventricle returned to normal dimensions and symptoms disappeared. The incidence of right ventricular dilatation was considerably higher (p = 0.020) in patients with a transannular patch; the transatrial approach showed the opposite (p = 0.03), and patients presented with lower QRS duration (p = 0.007), although no difference could be found between survival after both surgical techniques. Effects of early timing (correction < 6 months) on right ventricular dysfunction could not be established. Conclusions. Severe right ventricular dilatation and pulmonary regurgitation secondary to outflow tract repair in tetralogy of Fallot are frequently occurring sequelae developing slowly over time. Indications for pulmonary valve replacement remain controversial because echocardiographic findings or arrhythmias are not always accompanied by deterioration of clinical condition. However, right atrial dilatation and additional hemodynamic lesions demand increased vigilance. Transatrial repair is associated with a favorable outcome. © 2002 by The Society of Thoracic Surgeons.