Patients’ Baseline Characteristics
Among the 228 participants, except for 35 patients without follow-up data, the remaining 193 patients had a mean age at initial PBPV of 2.56 years (median: 1.58 years, IQR: 11 months–3.13 years, range: 21 days–14.25 years), mean weight at initial PBPV of 12.80 kg (median: 11 kg, IQR: 9–15 kg, range: 2.24–55 kg), mean height at initial BPV of 79.21 cm (median: 75 cm, IQR: 68.75–84 cm, range: 46–159 cm), mean BSA at initial BPV of 0.474 m2 (median: 0.437 m2, IQR: 0.384–0.485m2, range: 0.162–1.376 m2), mean initial peak echocardiographic PVS gradient of 60.66 mmHg (median: 53 mmHg, IQR: 41.99–73.62), and mean initial RV-PA PSEG of 54.58 mmHg (median: 49 mmHg, IQR: 33–66.25). The mean RV-PA PSEG post‐valvuloplasty was 19.19 mmHg (median: 14 mmHg, IQR: 9–22.5 mmHg), mean initial RV/systemic pressure ratio was 0.82 (median: 0.71, IQR: 0.60–0.94), and mean RV/systemic pressure ratio post‐valvuloplasty was 0.47 (median: 0.42, IQR: 0.35–0.52). The mean balloon/annulus ratio was 1.23 (median: 1.20, IQR: 1.20–1.25). The average pulmonary annulus diameter was 12.35 mm (median: 12.3 mm, IQR: 10.2 mm–14.08 mm) measured by angiography. (Table 1, Figure 1).
Immediate results of percutaneous balloon pulmonary valvuloplasty
All 193 patients with follow-up data had preoperative and postoperative cardiac catheterization results. Immediately after PBPV, the right ventricular (RV) systolic pressures reduced significantly from 77.23 mmHg (median: 71 mmHg, IQR: 56–91 mmHg) to 43.81 mmHg (median: 40 mmHg, IQR: 33.5–48 mmHg), the pulmonary artery (PA) systolic pressure increased from 22.40 mmHg (median: 22 mmHg, IQR: 19–26 mmHg) to 24.27 mmHg (median: 24 mmHg, IQR: 21–27 mmHg), and RV-PA PSEG reduced significantly from 54.84 mmHg (median: 49 mmHg, IQR: 33–67 mmHg) to 19.50 mmHg (median: 14 mmHg, IQR: 9–23 mmHg) (Table 2). Immediate success was defined as a pulmonary gradient of <40 mmHg after PBPV, and the immediate success rate was 89.6%.