* Pediatric Cardiology. Policlinico Umberto I. University “La Sapienza” Rome, Italy
** Ultrasound Division, ASL Roma B, Rome, Italy.
*** Ultrasound Division, Ceprano Hospital, Ceprano, Italy.
Introduction
A "single ventricle" is defined as a heart missing the smooth (nontrabeculated) inflow region of either ventricles. The heart has one functioning ventricle with inflow from one or both atria. The atrioventricular connection is either double inlet (two atria connect to the single ventricle through two patent atrioventricular valves), single inlet (one atrium connects to the single ventricle through the atrioventricular valve) or common inlet (both atria connect to the single ventricle through a single atrioventricular valve).
Over the last 30 years, the surgical literature has been using a functional definition: Single ventricle is present when one of the two ventricles is so small that a series circuit is incompatible with survival. Single left ventricle is a relatively uncommon disorder in which the right ventricle is rudimentary and consists of only an arterial outflow. The single left ventricle communicates with the rudimentary right ventricle via a bulboventricular foramen (outlet foramen). The rarely observed single right ventricle occurs when no left ventricle is detected. Single ventricle most frequently occurs with transposition, but any ventriculo-arterial alignment can be seen. Subpulmonary stenosis is more prevalent than the combination of aortic arch obstruction and subaortic stenosis. Although rare, single ventricle can occur without stenosis of either pulmonary or aortic outflow.
Case report
This is the case of a 21-years-old patient G1P0, with non-contributive personal and family history. The father of the baby had an unknown congenital heart disease. At the 20-week ultrasound screening, stomach and spleen were seen in the left side and gallbladder was on the right. The umbilical vein was directed towards the liver, the heart was located on the right side of the thorax. We thought that there was a large ventricular septal defect because some of the interventricular septum was seen. The great vessels were transposed. The pulmonary artery was small, with turbulent flow. No other anomalies were detected.
The fetal echocardiography exam was performed at 22 weeks. The final report suggested a double inlet single ventricle. The structure we considered as a remnants of the interventricular septum was a thickened papillary muscle attached to the tricuspid valve. Great vessels were transposed and the main pulmonary artery was atretic but both pulmonary branches had a normal caliber.
After an extensive counseling, parents decided to continue their pregnancy and refused any kind of invasive procedure such an amniocentesis. The rest of the pregnancy was monitored at a tertiary care center.
Patient delivered via scheduled cesarean section at 38 weeks of gestation. The neonatal weight was 2250 grams and length was 44 cm, Apgar score was 8/9 at the 1st/5th minute respectively. Karyotype of the newborn was normal, 46 XY. The surgery, aortic-pulmonary shunt was performed without any complications. The little boy seems doing well while waiting for the final cardiac surgery.
Images 1,2: Images at the level of the 4-chamber view, note only one ventricle.