Anatomic variability and outcome in prenatally diagnosed absent pulmonary valve syndrome

We sought to describe current outcomes and risk factors for mortality for fetuses diagnosed with absent pulmonary valve syndrome (APV). Fetuses with APV were divided into two cohorts, those with underlying tetralogy of Fallot (TOF/APV) and those without underlying TOF and either an intact ventricular septum or small ventricular septal defect (APV/IVS).

The fetal echocardiographic database was reviewed from January 1, 2001, until June 1, 2010, and all subjects with a diagnosis of APV were included. Multiple clinical and fetal echocardiographic measurements were recorded. Statistical analysis was performed by χ2 analysis and t tests. Survival analysis was performed by Kaplan-Meier analysis. Significant relationships between variables were explored by regression analysis. Significance was set at p=0.05.

The cohort consisted of 15 fetuses with TOF/APV and 6 fetuses with APV/IVS. There were no fetal demises in either cohort. Survival to birth was 71% in the TOF/APV cohort and 83% in the APV/IVS cohort (p=0.62). Of subjects born alive, survival was 80% for both cohorts (p=0.95). However, in the APV/IVS cohort, transplantation-free survival was only 20%. Underlying single-ventricle physiology strongly predicted those who underwent heart transplantation (p=0.003, R2=0.50). For the entire APV cohort, left ventricular dysfunction (p=0.005, R2=0.41) and a higher pulmonary artery valve-to-aortic valve ratio (p=0.02, R2=0.34) predicted mortality.

Postnatal outcomes continue to improve for fetuses with APV syndrome. Left ventricular dysfunction and higher pulmonary artery valve-to-aortic valve ratio accurately predict postnatal mortality for fetuses with APV.