Immediate effects and outcome of in-utero pulmonary valvuloplasty in fetuses with pulmonary atresia with intact ventricular septum or critical pulmonary stenosis

Abstract

Objective: To assess the immediate effects of fetal pulmonary valvuloplasty on right ventricular (RV) size and function as well as in-utero RV growth and postnatal outcome.

Methods: Patients with pulmonary atresia with intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS) who underwent fetal pulmonary valvuloplasty at our center between October 2000 and July 2017 were included. Echocardiographic data obtained before and after the procedure were analyzed retrospectively (median interval after intervention, 1 (range, 1-3) days) for ventricular and valvular dimensions and ratios, RV filling time (duration of tricuspid valve (TV) inflow/cardiac cycle length), TV velocity time integral (TV-VTI) × heart rate (HR) and tricuspid regurgitation (TR) velocity. Longitudinal data were collected from only those fetuses followed up in our center. Outcome was assessed using the scoring system as described by Roman et al. for non-biventricular outcome.

Results: Thirty-five pulmonary valvuloplasties were performed in our institution on 23 fetuses with PAIVS (n = 15) or CPS (n = 8). Median gestational age at intervention was 28 + 4 (range, 23 + 6 to 32 + 1) weeks. No fetal death occurred. Immediately after successful intervention, RV/left ventricular length (RV/LV) ratio (P ≤ 0.0001), TV/mitral valve annular diameter (TV/MV) ratio (P ≤ 0.001), RV filling time (P ≤ 0.00001) and TV-VTI × HR (P ≤ 0.001) increased significantly and TR velocity (P ≤ 0.001) decreased significantly. In fetuses followed longitudinally to delivery (n = 5), RV/LV and TV/MV ratios improved further or remained constant until birth. Fetuses with unsuccessful intervention (n = 2) became univentricular, all others had either a biventricular (n = 15), one-and-a-half ventricular (n = 3) or still undetermined (n = 3) outcome. Five of nine fetuses with a predicted non-biventricular outcome, in which the procedure was successful, became biventricular, while two of nine had an undetermined circulation.

Conclusion: In selected fetuses with PAIVS or CPS, in-utero pulmonary valvuloplasty led immediately to larger RV caused by reduced afterload and increased filling, thus improving the likelihood of biventricular outcome even in fetuses with a predicted non-biventricular circulation. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Keywords: congenital heart disease; fetal cardiac intervention; fetal pulmonary valvuloplasty; pulmonary atresia with intact septum.

Figure 1

Cardiac measurements before and after completely or partially successful fetal pulmonary valve intervention in 21 fetuses with pulmonary atresia with intact ventricular septum or critical pulmonary stenosis. Patients 6 and 23 were excluded from (c) and (e) due to exclusive retrograde filling of right ventricle by severe pulmonary regurgitation. HR, heart rate; RV/LV ratio, right to left ventricular length ratio; TR Vmax, maximum velocity of tricuspid regurgitation; TV/MV ratio, tricuspid to mitral valve annular diameter ratio; TV‐VTI, tricuspid valve velocity time integral.

Figure 2

Apical four‐chamber views of Patient 9 before (a) and 2 days after (b) intervention; arrows mark points of measurement for tricuspid and mitral valve annular diameter and right (RV) and left (LV) ventricular length; note increase in RV length and tricuspid valve diameter after intervention. Pulsed‐wave Doppler traces with RV filling times of Patient 15 before (c) and after (d) intervention; note change from short monophasic RV filling of 25% (107/422 ms) of cardiac cycle length before intervention to longer biphasic RV filling of 39% (197/505 ms) of cardiac cycle length after intervention. LA, left atrium; RA, right atrium; TR, tricuspid regurgitation.

Figure 3

Continuous‐wave (CW) Doppler traces of tricuspid regurgitation (TR) in Patient 11 before and after intervention; pressure gradient was reduced from 75 mmHg (4.34 m/s) (a) to 49 mmHg (3.50 m/s) (b). (c) CW Doppler tracing of blood flow across pulmonary valve (PV) with remaining antegrade gradient of 49 mmHg and new pulmonary regurgitation (PR) in Patient 9 after intervention (c).

Figure 4

Longitudinal development of right to left ventricular length (RV/LV) ratio (a) and tricuspid to mitral valve annular diameter (TV/MV) ratio (b) in five fetuses that underwent fetal pulmonary valvuloplasty. Plotted are measurements before intervention, immediately after intervention and immediately postpartum, with intervention indicated by asterisks. In Patients 11 and 19, two measurements were performed before intervention. Measurement of TV/MV ratio immediately after intervention is missing for Patient 19 (b). , Patient 6; , Patient 11; , Patient 18; , Patient 19; , Patient 21.

Figure 5

Circulation outcome in 23 fetuses that underwent fetal pulmonary valvuloplasty according to prediction score by Roman et al.15, a four‐point scoring system indicating non‐biventricular (BV) circulation after birth for fetuses with score of 3, with 100% sensitivity and 75% specificity. Note that 5/10 patients with predicted non‐BV outcome had BV circulation. 1.5 V, one‐and‐a‐half ventricle circulation; UV, univentricular circulation.