Effect of Balloon Pulmonary Valvuloplasty on Growth of Pulmonary Annulus in Infants with Tetralogy of Fallot.

Percutaneous balloon pulmonary valvuloplasty (PBPV) is an alternative intervention in infants with Tetralogy of Fallot (TOF). It can not only improve hypoxia but also promote pulmonary annulus (PA) growth. In this study, we evaluated the effect of PBPV on PA growth in infants with TOF. To eliminate the effect of the systemic to pulmonary shunt (SPS) that may promote PA growth, we divided TOF infants into 2 groups: group A, patients who underwent PBPV with or without other SPS, and group B, patients who attempted SPS but without PBPV. Sixty patients were included, 28 patients in group A and 32 patients in group B. Age at the time of intervention in group A (range, 0.4-5.4; median 1.4 months) was lower than that in group B (range, 2.3-7.7; median 4.8 months), p-value 0.02. The body weight in group A (range, 3-5.5; median 3.7 kg) was also lower than that in group B (range 4.1-6.4; median 5.9 kg), p-value 0.02. Echocardiographic data at the mean follow-up period of 37.2 months (3-88 months) in group A and 39.6 months (6-95 months) in group B demonstrated an increase in mean PA diameter from 5.0 ± 1.3 mm to 10.2 ± 2.9 mm, p-value < 0.001 in group A; and from 6.2 ± 2 mm to 9.5 ± 2.9 mm, p-value < 0.001 in group B. The median PA z-score increased from - 3.4SD (- 3.9 to - 2.6SD) to - 1.8SD (- 2.5 to - 0.8SD), with the p-value of 0.002 in group A; and increased from - 2.9SD (- 4.5 to - 1.3SD) to - 2.7SD (- 3.6 to - 1.4SD), with the p-value of 0.73 in group B. By using the PA z-score as the absolute value, there was a statistically significant increase in the PA z-score during follow-up in group A, but not in group B. Balloon pulmonary valvuloplasty in infants with TOF can facilitate the growth of the pulmonic annulus even after eliminating the effect of the systemic to pulmonary shunt.

Outcomes of duct stenting and modified Blalock-Taussig shunt in cyanotic congenital heart disease with duct-dependent pulmonary circulation.

BACKGROUND: Transcatheter ductus arteriosus stenting (DS) is emerging as an alternative method to modified Blalock-Taussig shunt (MBTS) in providing pulmonary blood flow in cyanotic congenital heart disease (CCHD) with duct-dependent pulmonary circulation. OBJECTIVE: To evaluate post-procedural outcomes and survival between patients undergoing DS and MBTS. METHODS: All infants ≤ 60 days of age having CCHD with diminished pulmonary blood flow who underwent palliative procedure either with MBTS or DS at King Chulalongkorn Memorial Hospital during January 1st, 2013 and December 31th, 2017 were retrospectively reviewed. RESULTS: 98 patients were included; 34 patients underwent a transcatheter DS and 64 patients underwent MBTS. There was no significant difference in post-procedural outcomes and overall mortality rate between two groups (17.6% in MBTS group and 6.1% in DS group, p = 0.09). Single ventricle morphology was the major risk factor associated with increased mortality compared with biventricular morphology (aHR 3.9, 95% CI 1.49-10.2, p = 0.01). There was similar number of early and pre-repair additional interventions focusing on MBTS/DS patency between two groups. The MBTS group had a greater number of early interventions on PA branch stenosis related to baseline diagnosis. Risk factors associated with additional intervention were pre-existing pulmonary branch stenosis (aHR 2.54, 95% CI 1.3-4.97, p = 0.006) and body weight less than 2.5 kg (aHR 3.33, 95% CI 1.57-7.08, p = 0.003). Having pulmonic valve perforation or balloon pulmonary valvuloplasty to promote antegrade pulmonary blood flow could result in a lower number of additional interventions required before definitive repair. CONCLUSION: Duct stenting is a feasible and safe alternative to MBTS in cyanotic infants with duct-dependent pulmonary circulation. However, mortality rate was significantly higher in patients with single ventricle that required careful follow-up after procedure.