Rate and Outcomes of Pulmonary Stenosis and Functional Pulmonary Atresia in Recipient Twins with Twin-Twin Transfusion Syndrome

Abstract

Objective: To evaluate the rate of pulmonary stenosis and functional pulmonary atresia (PS/PA) in recipient twins prior to fetal surgery for twin-twin transfusion syndrome (TTTS) and their pre- and postnatal outcomes. Methods: We carried out a prospective study including 260 cases of TTTS. Echocardiography was performed before laser surgery to detect the presence of PS/PA. The outcomes of recipients with and without PS/PA were compared. The need of postnatal cardiac interventions and the survival rate at 6 months of age were also evaluated. Results: PS was observed in 16/260 (6.2%) of recipient twins and PA in 12/260 (4.6%). After fetal surgery, 10/28 (35.7%) recipients died, 9/28 (32.1%) showed in utero regression, and 9/28 (32.1%) had persistence of PS/PA. Postnatally, seven recipients underwent percutaneous balloon pulmonary valvuloplasty, one required surgical valvotomy and one palliative surgery. Pregnancies with recipient twins with PS/PA had lower survival of at least one twin (67.9 vs. 83.6%, p = 0.045) and lower overall survival (57.1 vs. 72.8%, p = 0.015) at 6 months of age. Conclusion: PS and PA were observed in 10.8% of recipients. Among these, about one third showed persistence of pulmonary valve pathology after delivery, which stresses the need for strict follow-up.

Differential Changes in Myocardial Performance Index and Its Time Intervals in Donors and Recipients of Twin-to-Twin Transfusion Syndrome before and after Laser Therapy

“…Our findings also support previous series reporting that cardiac function is worse in recipients than donors [13-15, 25]. It can be attributable to major changes in preload and afterload that could even lead to hypertrophic cardiomyopathy and right ventricular outflow tract abnormalities [26]. …”

Acquired right ventricular outflow tract obstruction in twin‐to‐twin transfusion syndrome; a prospective longitudinal study

“…It has been suggested previously that recipients in higher Quintero stages of TTTS are more likely to develop postnatal RVOTO . In this prospective cohort, prenatal RVOTO at TTTS diagnosis seem to occur more frequently in the advanced stages of TTTS, but postnatal RVOTO was equally found in all Quintero stages.…”

“…In the current study, pulmonary stenosis or atresia at the time of TTTS diagnosis resulted in severe postnatal valvular stenosis in 33% of cases (3/9) and in mild stenosis in 11% (1/9) . In addition, 2% of cases with initial normal FVW‐PV at TTTS diagnosis developed abnormal FVW‐PV in the weeks after laser therapy, which progressed to mild valvular stenosis in the neonatal period.…”

“…All prenatal pulmonary atresia cases in our study showed severe tricuspid insufficiency. The FVW‐PV normalized when the right ventricle function was restored after laser therapy, proving the concept that the pulmonary atresia at time of TTTS diagnosis is a functional. Only one prenatal pulmonary atresia case resulted in postnatal severe valvular pulmonary stenosis.…”

“…The pathophysiology of RVOTO in TTTS is not fully understood, and risk factors for progression to postnatal RVOTO are still difficult to determine. Most studies focus on preintervention assessment of RVOTO, because systematic longitudinal echocardiographic follow‐up of all recipients after laser therapy is difficult to establish in fetal therapy centers . This impedes knowledge on the complete spectrum of RVOTO .…”