Prenatal diagnosis of redundant foramen ovale flap aneurysm prolapsing into mitral valve mimicking coarctation of aorta

Type III fetal redundancy of the foramen ovale flap mimics hemodynamic changes of mitral stenosis

Type III redundancy of the foramen ovale flap (RFOF) mimics hemodynamic changes of mitral stenosis(MS), which has not been particularly highlighted in previous literature but carries a favorable prognosis.

Foramen ovale flap aneurysm in fetuses associated with and without heart defects: Prenatal diagnosis, imaging, in-utero hemodynamics, pregnancy, and postnatal outcomes

BACKGROUND

Isolated redundant foramen ovale flap aneurysm (RFOA) in the absence of restrictive foramen ovale is believed to be a cause for pseudocoarctation of aorta since the impediment of blood flow to the left heart can be severe, resembling the picture of left ventricular hypoplasia with retrograde aortic flow. The primary objective of the study is to find whether RFOA is always a benign lesion. The main focus of the study is to share my experience in particular on fetuses having redundant foramen ovale flap aneurysm developing into coarctation of aorta and to study the associated factors.

METHODS

Retrospective study (January 2020 to June 2023). All fetuses with RFOA associated with and without congenital heart defects were included. Fetuses with restrictive foramen ovale and RFOA with single ventricle hearts were excluded. The imaging, in-utero hemodynamics, pregnancy, and postnatal outcomes with at least 3 months follow-up were presented.

RESULTS

During the study period, a total of 1499 fetal echocardiography were performed. Twenty-two fetuses with RFOA were included. Fourteen fetuses had isolated RFOA and eight had associated abnormalities [extracardiac (n = 5); intracardiac (n = 2), Both (n = 1)]. Genetic evaluation were performed only in fetuses with associated defects were normal. Postnatally all isolated RFOA fetuses had no aortic arch obstruction. Fetuses with associated aberrant right subclavian artery, isolated left superior vena cava, absent ductus venosus and ventricular septal defects developed aortic arch obstruction after birth. RFOA causes smallish left ventricle in fetuses with tetralogy of Fallot which recovered to normal size postnatally.

CONCLUSION

Isolated RFOA can be benign, however, if it is associated with cardiac or extracardiac anomalies predominantly resulted in aortic arch obstruction. Though it is a cause for pseudocoarctation of aorta, through postnatal reassessment of aortic arch is mandatory. Careful search for intracardiac and systemic venous anomalies is recommended. It created confusion regarding adequacy of left ventricle when associated with congenital heart defects.

Clinical presentation, conventional/4D spatio-temporal image correlation imaging findings, pregnancy and early postnatal outcomes in fetuses having anomalies of systemic venous return in the absence of significant intracardiac defects: A retrospective study from two centres in Southern India

BACKGROUND

Recent advances in fetal ultrasound imaging, especially four-dimensional (4D) spatio-temporal image correlation techniques permit detailed evaluation of the fetal venous system and its abnormalities. In this report, we present the clinical presentation, conventional/4D spatio-temporal image correlation imaging findings, pregnancy, and early postnatal outcomes in fetuses having anomalies of systemic venous return in the absence of significant intracardiac defects from two centres in southern India.

OBJECTIVES

To report the clinical presentation, conventional/4D spatio-temporal image correlation imaging findings, pregnancy, and early postnatal outcomes in fetuses having anomalies of systemic venous return in the absence of significant intracardiac defects from two centres in Southern India.

METHODS

Retrospective study (October 2017 to March 2022). All fetuses referred with abnormal cardiac imaging findings who were diagnosed to have anomalies of systemic venous return in the absence of significant intracardiac defects were included. Imaging techniques like 2D with color and 4D spatio-temporal image correlation fetal imaging were used to evaluate systemic venous anomalies. Systemic venous anomalies were grouped into cardinal venous anomalies and umbilico-portosystemic venous anomalies.

RESULTS

Thirty-nine fetuses were included; this represented 4.4% of all cardiac anomalies diagnosed during the study period. Cardinal venous anomalies were seen in 29 fetuses (74%); the mean gestation age at diagnosis was 25.5 ± 3.4 weeks. Absent dilated coronary sinus was associated with anomalous drainage of superior caval vein through completely unroofed coronary sinus into the left atrium (n = 3) which resulted in cyanosis after birth in all infants. Among the three cases, one underwent surgery at 6 months of age due to a progressive increase in cyanosis (Spo2 78%) and others are awaiting surgery. A prenatal genetic evaluation was performed in 17 (58.6%). Cardinal venous anomalies were not associated with genetic abnormalities. Live births occurred in all fetuses with cardinal venous anomalies. Umbilico-portosystemic venous anomalies were seen in 10 (26%). The mean gestation age at diagnosis was 26.5 ± 4.5 weeks. Except in a fetus with the extrahepatic portosystemic shunt (umbilical vein to iliac vein), the genetic evaluation was normal in our cohort. Extracardiac anomalies (n = 3/10; 30%) were seen in both intra (n = 1) and extrahepatic portosystemic shunts (n = 2).

CONCLUSION

Anomalies of systemic venous return in the absence of significant intracardiac, extracardiac, and genetic abnormalities carried an overall favorable prognosis in our cohort. Precise characterization of anatomic details using advanced imaging techniques helps in the understanding of this complex three-dimensional anatomy and in the prognostication of these anomalies.

Fetal Atrial Flutter Associated with Atrial Septal Aneurysm

Objective: To provide evidence that fetal atrial flutter (AF) caused by atrial septal aneurysm (ASA) can be completely cured by delivery. Methods: Cases series of three fetuses with ASA complicated by AF in late gestation, including hydrops fetalis in one case, were collected and completely followed up. Results: AF in all cases completely disappeared shortly after birth. New insights gained from this study are as follows: (1) PACs or bigeminy associated with ASA can progressively change to AF. (2) AF associated with ASA can cause hydrops fetalis and intrauterine treatment is needed; however, delivery is the definitive treatment. (3) AF associated with ASA completely resolves after birth. This is probably associated with changes in the circulation after birth, with no more blood flow crossing the foramen ovale and no turbulent flow in the ASA with reversal to hit the right atrial wall, activating ectopic pacemakers. Conclusions: This report may have clinical impact because it provides evidence that (1) in case of AF associated with ASA, the prognosis is much better than other causes and delivery should be strongly considered. (2) Fetuses diagnosed with AF should always be checked for the presence of ASA. (3) PAC/bigeminy related to ASA, different from isolated PAC, needs close follow-up for the development of SVT and AF. (4) Fetuses remote from term can benefit from intrauterine treatment to avoid hydrops fetalis, and to prolong gestation for maturity, early delivery is recommended once lung maturity is confirmed.

Fetal Atrial Septal Aneurysm: Follow-Up from Second to Third Trimester

Atrial septal aneurysm (ASA) is a rarely reported fetal finding. Its definition is variable, but the diagnosis is usually made when the foramen ovale flap extends at least halfway across the left atrium. It is considered a transient, self-limiting condition, but on occasion, it can be complicated by fetal arrhythmia or left ventricular (LV) inflow obstruction—if longstanding, this can lead to left heart hypoplasia. We present two cases of ASA diagnosed at the second trimester scan, one of which was subsequently complicated by LV inflow obstruction and prenatal suspicion of hypoplastic aortic arch. This report is a good illustration of how structure follows function: a small LV preload can lead to a decreased LV output, which in turn will end up in a hypoplastic LV and outflow tract—all this is reversible after birth, due to the physiological circulatory modifications that occur in the newborn.