During cardiac surgery conventional heart-lung bypass machines in very small infants requires filling the bypass machine circuit with blood donated from a donor.  Evidence is increasingly accumulating to suggest that the transfused blood received during cardiopulmonary bypass (CPB) has a significantly detrimental impact on the child by triggering a profound inflammatory response.  The magnitude of the inflammatory response is known to be responsible for many of the life threatening complications of cardiac surgery.

This project’s goal is the continued development of the miniaturization of the bypass circuit resulting in a bloodless prime of the circuit.  The project involves utilizing a CPB system known as Minimal Extracorporeal Circulation System (MECC) Bypass, which has been successfully utilized in adults, but the system has not been applied or investigated in children.

The goals of the project are:

• To further refine the experimental miniaturization CPB circuit into a system that can more easily be applied to the clinical arena (close the gap between experimental concept and the routine clinical application).
• Further characterize the inflammatory benefits of Miniaturized Bloodless Prime Bypass using refined technology.

Myocardial Protection and Support in Cyanotic Congenital Heart Disease
Henry Michael Spotnitz, M.D.
Columbia University
Amount Awarded: $52,000

Synopsis of research project:
Dr. Spotnitz and colleagues are proposing research to understand the development of ventricular stiffness in patients with single ventricle. Techniques from the past will be used to measure stiffness during the Fontan operation to compare stiffness during the Norwood, Glenn and Fontan operations. They will also use a special echocardiography technique to measure the thickness and mass of the ventricle, because water retention in the ventricle can cause stiffness, and water retention increases mass and thickness. Ventricular stiffness will also be measured by techniques that do not require surgery. If it is known that a ventricle is stiff before surgery is started, treatments may be used to reduce stiffness or special management techniques can be planned during surgery.

Ventricular stiffness will be measured before, during and after the three stages of surgery for single ventricle. By comparing the results at the three stages and by relating stiffness to the results of surgery, Dr. Spotnitz and colleagues hope to develop a plan for a clinical trial that will improve the results of surgery for all blue babies with single ventricle. The results of these studies, by improving understanding of how these operations affect the heart, could improve the results of surgery for all babies with congenital heart defects.