“Hepatic Function in Single Ventricle Congenital Heart Disease Before and After the Fontan Operation”

Doctor's Name: 
Meryl Cohen MD
Hospital/Institution: 
Children’s Hospital of Philadelphia

“Hepatic  Function in Single Ventricle Congenital Heart Disease Before and After the Fontan Operation”

The normal human heart has 2 pumping chambers, the right ventricle and the left ventricle.  The right ventricle pumps blood to the lungs and the left ventricle to the body.  Some patients are born with only 1 functioning ventricle and, thus, these patients have single ventricle congenital heart disease.  Patients with single ventricle heart disease undergo a series of operations, the last of which is called the Fontan operation.  The Fontan operation creates a circulation in which all venous blood drains directly into the pulmonary arteries, thus there is no ventricle to pump blood to the lungs.  This circulatory strategy is life-saving, but does have drawbacks and liver injury has emerged as an important complication. 

The timing of liver injury in patients with Fontan circulation is not known.  We recently completed a retrospective study of liver histology at autopsy that suggested that, in some patients, liver injury even occurs prior to the Fontan.  Other studies suggest time from Fontan surgery is a risk factor for this liver injury. Further study of liver injury prior to Fontan and of the onset of liver injury after Fontan are needed.

We aim to use non-invasive testing (blood tests, liver ultrasound) to determine if liver dysfunction exists in patients before the Fontan operation.  These tests will then be repeated 3 to 6 months after Fontan operation to determine if liver function worsens soon after Fontan.  Also, we will determine if liver abnormalities present before the Fontan predict adverse post-operative outcomes.

All patients with single ventricle congenital heart disease who are scheduled for the Fontan operation at CHOP will be recruited for the study.  Patients will range in age from 1 to 4 years-old.  Consent will be obtained from the patient’s parents.  Enrolled patients will then have blood tests and liver ultrasound performed at their pre-surgical visit before Fontan operation.  The clinical course of each patient after Fontan will be followed and the patients will return 3 to 6 months after Fontan for repeat blood tests and liver ultrasound.

Abnormalities in blood tests and ultrasound before the Fontan will be described.  We hypothesize that, in some patients with single ventricle heart disease, liver dysfunction exists prior to the Fontan.  The blood test and ultrasound results obtained prior to Fontan operation will then be compared to those obtained 3 to 6 months after Fontan to determine if hepatic function worsens soon after Fontan operation.  We hypothesize that liver injury continues after creation of the Fontan circulation and that results of blood tests and liver ultrasound will worsen after Fontan operation.

Improved understanding of liver injury in patients with single ventricle congenital heart disease is very important.  Liver disease is associated with complications such as liver cancer and even with death.  In addition, severe liver disease can prevent patients from undergoing heart transplantation, a therapeutic option for some patients with single ventricle heart disease.

Award Date 1: 
2011
Award Amount 1: 
$49,047