"The results of our study should not only be useful for physicians as they counsel their patients undergoing heart surgery, but may also help to decide between medical or surgical treatments, based on a patient's unique characteristics and genetic make-up", said Mark Stafford-Smith, M.D., Duke cardiothoracic anesthesiologist.

Prior to surgery, the researchers performed genetic analysis of blood samples paying particular attention to twelve candidate polymorphisms on seven genes.

The researchers correlated the individual polymorphisms with the peak levels of creatinine measured after surgery. Since race has already been determined to be an important independent predictor of kidney damage after surgery, the researchers performed separate analyses of Caucasians and African-Americans.

In Caucasians, the researchers found that patients having two polymorphisms involved in the inflammatory response angiotensinogen 842C and interleukin 6-572C had on average an 121 per cent increase in creatinine, which is equivalent to a 55 per cent reduction in the kidney's ability to filter waste.

It is in this vasoconstriction phenomenon where it appears that different polymorphisms may explain the increased kidney damage seen in African-Americans, who if they possess two polymorphisms involved in vascular responsiveness had a 162.5 percent increase in creatinine in the blood. This translates into a 60 percent reduction in the kidney's filtering ability

"The polymorphisms of these genes, since they are vital to controlling blood flow in the kidney, may contribute not only to the initial insult during low blood flow, but also throughout the recovery phase", Stafford-Smith said

MEDICA.de; Source: Duke University Medical Center