METHODS:
This was a retrospective study conducted in a single tertiary fetal
medicine center. The cases diagnosed with PAVSD between January 2017 and
December 2022 were identified on the electronic database of our fetal
echocardiography clinic. All prenatal echocardiographies were performed
using Voluson E6 (GE Healthcare Ultrasound, Milwaukee, Wisconsin)
equipped with a curved transabdominal probe by the same expert fetal
medicine consultant (OD) in a systematic manner, usually twice a month
for each pregnancy. The cases with additional complex cardiac defects
were not included. Long and short-axis views were used to assess
pulmonary vasculature and comprehensive cardiac anatomy. Axial,
sagittal, and coronal views of the aorta were used to detect MAPCAs. The
vessels which supply blood to the pulmonary parenchyma were also
identified, beginning from the parenchymal tissue and following towards
the systemic origin on color Doppler. Vascular blood flow was evaluated
using high-definition (HD) Doppler, applying a pulse repetition
frequency of 0.3–0.6 kHz. As a routine clinical protocol, an informed
consent was taken from each patient approving the publication of the
ultrasound images and clinical data in case of a clinical research,
provided that their identities and personal information were kept
confidential. The study protocol was approved by the institutional
ethical committee (22.03.2023, No. 46), and it was carried out following
the principles of the Declaration of Helsinki.
Details of ultrasonographic findings such as the presence or absence of
DA, pulmonary arteries, and the confluence of the pulmonary arteries,
the diameters of the right pulmonary artery (RPA) and left pulmonary
artery (LPA), the source of blood supply to the lungs (DA, MAPCAs or
double supply), the origin of the MAPCAs were obtained from the fetal
echocardiography reports and archived sonographic images. The pulmonary
blood supply was assumed as ’ductus arteriosus” if retrograde flow was
displayed in DA adjacent to the aortic isthmus in 3VT plane or from the
undersurface of the aortic arch, distal to the left subclavian artery
towards the pulmonary artery without any intervening branches in
sagittal plane. The vascular supply was assumed as MAPCAs when
collaterals that fed the pulmonary parenchyma were detected to originate
from the main branches of the aortic arch, coronary arteries, or
descending aorta. Confirmation of the fetal echocardiographies was
sought from neonatal echocardiography and angiography with cardiac
catheterization performed in collaborated pediatric cardiology clinic
for all live-born neonates. Postnatal confirmation of the fetal
echocardiographies of the babies who had undergone surgery was made by
operation reports. TOP cases could not be confirmed due to the families’
refusal of an autopsy. Measures of association for categorical variables
were analyzed with Pearson Chi-square test. All analyses were performed
using SPSS version 22 (IBM Corp., Armonk, NY, USA). The Mann-Whitney U
test was used for comparing the surgical intervention time between
groups. A p-value of <0.05 was considered statistically
significant.