The Jonker Lab is delighted to have been awarded an R01 to study growth and function of the fetal heart in a sheep model of right functionally univentricular heart, or hypoplastic left heart.

The left ventricle pumps blood to the body, but sometimes it doesn't grow in the fetus. In fetal life, the presence of the arterial shunt between the pulmonary artery and the aorta permits the right ventricle to take over. This is possible because the placenta oxygenates the fetal blood. At birth, though, the infant must breathe, the right ventricle must circulate blood to the lungs, and the shunt closes. A series of palliative surgeries is necessary beginning in the newborn to allow the infant to live.

Not much is known about how the right ventricle grows and functions in fetal life. How does the loss of the left ventricular contribution affect loading of the right ventricle? How does that affect circulating hormones, and growth and maturation of the cardiac myocytes? Would more myocytes help the right ventricle be more resilient?

We look forward to addressing these questions, and more, as we complete the experiments in "Regulation of cardiomyocyte growth in a fetal ovine model of reduced left ventricular filling"!