* Pediatric Cardiology. Policlinico Umberto I. University “La Sapienza” Rome, Italy
** Ultrasound Division, ASL Roma B, Rome, Italy.
*** Reparto di ostetricia e ginecologia, Ospedale Fatebenefratelli San Pietro Rome, Italy.
**** Ultrasound Division, Ceprano Hospital, Ceprano, Italy.
Introduction
Persistent left superior vena cava is the most common form of anomalous venous drainage involving the superior vena cava. It results from failure of the left horn of the embryonic sinus venosus, left anterior and common cardinal veins to involute.
A persistent left superior vena cava starts at the junction of the left jugular and subclavian veins, runs anterior to the aortic arch and left pulmonary artery and on the lateral border of the left atrium. It joins the coronary sinus in the posterior left atrioventricular groove. In most of the cases (92%) it enters the right atrium through the orifice of an enlarged coronary sinus.The rest of the cases drain into the left atrium [1,2]. A persistent left superior vena cava is seen in 0.3%–0.5% of the normal population [1,2] and 1.5%–10% of patients with other congenital heart abnormalities [2,3].
Various reports have described the presence or absence of the right superior vena cava in cases of persistent left superior vena cava, and the frequency of associated cardiac anomalies.
Detection of the left superior vena cava should be followed by a meticulous inspection of the fetal anatomy as it is frequently associated with heterotaxy syndromes, other cardiac/non-cardiac malformations and aneuploidies. Presence of the associated anomalies determines the outcome. Isolated finding of the left persistent superior vena cava is a benign vascular anomaly and does not affect the neonatal outcome [4].
Case report
This is a 34-year-old G2 P1 with a history of the gestational diabetes in the previous pregnancy. She started her insulin therapy as early as in the first trimester of the current pregnancy. The first trimester scan performed at 12 weeks was normal (NT=0.8 mm) but there was a reverse flow in ductus venosus.
Second trimester scan at 21 weeks of gestation did not detect any anomalies except of increased amount of the amniotic fluid (AFI-24 cm), single choroid plexus cyst and a slight dilation of the coronary sinus.
The ultrasound examination of the heart at 30 weeks of gestation showed dilated coronary sinus and persistent left superior vena cava. The left superior vena cava was located to the left of the pulmonary artery at the 3-vessel view. The right superior vena cava was present as well. The amount of the amniotic fluid was markedly increased (AFI = 34 cm).
The follow-up heart scan at 35 weeks revealed a dyskinetic left ventricle, a very dilated right ventricle and a restrictive foramen ovale. Fetal Doppler was normal but the amount of the amniotic fluid was decreased (AFI = 10 cm).
Patient delivered via scheduled cesarean section at 36 weeks. The baby was a boy of 2800 grams and Apgar score 9/9 at 1st and 5th minute, respectively. The newborn presented micropenis (that afterward was found to be a buried penis - the shaft of the penis is literally buried under excessive skin and fat) and severe bilateral hips dislocation. Foramen ovale closed spontaneously and echocardiography performed the third day after delivery, found atrial and ventricular septal defect, both of 3 mm wide. The karyotype showed 22q13 microdeletion and a duplication of 4p16.3 region.
The newborn was dismissed from the hospital after 2 months. He is 6-months-old at the moment, presents with torticollis and plagiocephaly maybe due to long hospitalization, lactose intolerance and failure to thrive and is regularly followed-up by various specialists.
Images 1- 4: 4-chamber view, images show dilated coronary sinus and persistent left superior vena cava (LSVC).