Pulmonary Artery Hypoplasia in Neonates With Tetralogy of Fallot

Outcomes of Neonates Born with Symptomatic Tetralogy of Fallot and Absent Ductus Arteriosus

OBJECTIVE

To test the hypothesis that neonates with symptomatic tetralogy of Fallot (TOF) and absent ductus arteriosus (ADA) have worse clinical outcomes compared with those with a ductus arteriosus (DA), and that this difference is driven by those born with ADA and with critically deficient pulmonary blood flow (CDPBF).

STUDY DESIGN

We performed a retrospective, multicenter cohort study of neonates who underwent intervention for symptomatic TOF comparing death and reintervention between subjects with and without a DA identified on fetal echocardiogram or on echocardiogram performed in the first postnatal day. Exclusion criteria were as follows: inability to define DA status, collaterals supplying pulmonary blood flow, atrioventricular septal defect, and absent pulmonary valve. We defined CDPBF as undergoing a procedure to augment pulmonary blood flow on the date of birth or extracorporeal membrane oxygenation prior to such a procedure.

RESULTS

The study cohort included 519 patients, among whom 11% had ADA. Patients with ADA were more likely to have a genetic syndrome and had smaller branch pulmonary artery size. In analyses adjusting for center, interventional treatment strategy, genetic syndrome, and minimum branch pulmonary artery size, ADA was associated with higher mortality risk (adjusted hazard ratio of 2.37 (95% CI: 1.07,5.27; P = .034). Seven patients had CDPBF (1.3% of the entire cohort and 12% of patients with ADA).

CONCLUSIONS

A minority of symptomatic TOF neonates have ADA, which is associated with higher adjusted mortality risk compared with those with a DA. CDPBF appears to be a rare but important entity in this population.

Assessment of Pulmonary Arterial Vascular Impedance in Fetuses With Tetralogy of Fallot

OBJECTIVE

To evaluate the vascular impedance of the pulmonary arteries in fetuses with tetralogy of Fallot (TOF) by Doppler echocardiography.

METHODS

A total of 42 fetuses with TOF (TOF group) and 84 gestational age-matched normal fetuses (control group) were prospectively collected from the Second Xiangya Hospital of Central South University from August 2022 to January 2023. The severity of TOF was classified into mild TOF (z score ≥-2), moderate TOF (-4 < z score < -2), or severe TOF (z score ≤-4) according to the z score value of the pulmonary annulus diameter. The pulsatility index (PI) of the main pulmonary artery (MPA), distal left pulmonary artery (DLPA), and distal right pulmonary artery (DRPA) were measured by pulsed-wave Doppler. The differences in clinical data and echocardiographic parameters between TOF group, control group, and TOF subgroups were compared.

RESULTS

Compared with the control group, MPA-PI increased significantly, whereas DLPA-PI and DRPA-PI decreased in TOF group (all P < .001). There were no significant differences in MPA-PI and DRPA-PI among mild TOF, moderate TOF, and severe TOF (all P > .05). However, DLPA-PI decreased significantly in severe TOF compared with mild TOF (P < .05).

CONCLUSION

Fetuses with TOF presented increased vascular impedance in the pulmonary trunk and decreased impedance in distal pulmonary artery branches. Further large and follow-up studies are needed to demonstrate the associations between those changed vascular impedances and the development of PA in patients with TOF.

Editor-in-Chief's Top Picks From 2023

Each week, I record audio summaries for every paper in JACC, as well as an issue summary. This process has become a true labor of love due to the time they require, but I am motivated by the sheer number of listeners (16M+), and it has allowed me to familiarize myself with every paper that we publish. Thus, I have selected the top 100 papers (Original Investigations, Review Articles, Society Documents, and the Global Burden of Diseases) from distinct specialties each year. In addition to my personal choices, I have included papers that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these abstracts in this issue of JACC, as well as their Central Illustrations∗ and podcasts. The highlights comprise the following sections: Aorta; Basic and Translational Science; Cardiac Failure, Myocarditis, and Pericarditis; Cardiomyopathies and Genetics; Congenital Heart Disease; Coronary, Peripheral, and Structural Interventions; Coronavirus; Health Promotion and Preventive Cardiology; Imaging; Metabolic and Lipid Disorders; Neurovascular Disease and Dementia; Rhythm Disorders and Thromboembolism; and Valvular Heart Disease.1-104 ∗ To view the full manuscript, including the full-sized Central Illustration, please refer to the original publication in JACC.

Complex Tetralogy of Fallot in an Acyanotic Adult Dog

•TOF with PA hypoplasia can be diagnosed in adult dogs. •MAPCAs were suspected on the basis of TTE detection of collateral vessels. •Acyanosis in this dog was attributed to multiple sources of pulmonary blood flow. •Augmented reality can provide unique imaging capabilities for complex heart defects.