Abstract
Although palliative pulmonary artery banding (PAB) is widely known to contribute to hospital discharge in infants with trisomy 18 (T18) and ventricular septal defect (VSD), the long-term prognosis remains unsatisfactory unless corrective surgery is performed. This study aimed to explore the possible reasons for poor outcomes of PAB in patients with T18 and VSD using hemodynamic and morphological evaluations. Echocardiography was used to assess the ventricular function via tissue Doppler imaging (TDI). Based on the values for healthy individuals, comparisons were made between infants with T18 and those with normal karyotype (NK) who underwent PAB for VSD. Right and left ventricular functions were impaired after PAB in infants with T18 and NK with VSD compared to those in healthy infants. The parameters indicating left ventricular function were similar after PAB between the infants with T18 and NK with VSD; however, the PAB-impaired right ventricular (RV) diastolic function was significantly worse in the infants in the T18 subgroup than those in the NK subgroup. Interestingly, RV diastolic dysfunction was significantly and positively correlated with elevated RV end-diastolic pressure and serum N-terminal pro-brain natriuretic peptide levels. Myocardial hypertrophy and interstitial fibrosis were observed in the resected RV muscle of patients with T18. RV diastolic dysfunction progressed after PAB in patients with T18 and a large VSD, possibly because of excessive RV hypertrophy. These findings may contribute to poor outcomes.