The results of a landmark study conducted at the Aurora St. Luke’s Medical Center have been presented at the Annual Meeting of the American College of Chest Physicians (CHEST 2005) in Montreal, Quebec, Canada. According to the study, the presence of heparin antibodies poses an independent risk for potential serious complications following cardiac surgery.
In addition, patients who do not develop the life-threatening drug reaction called Heparin Induced Thrombocytopenia (HIT) are also at a higher risk of postoperative complications.
The study followed patients undergoing coronary bypass grafting (CABG) and/or valves surgery for a period of 2 ½ years and demonstrated that the patients who tested positive for heparin/platelet factor 4 (HPF4) antibodies are at a demonstrably higher risk for serious postoperative adverse reactions including renal (kidney) failure requiring dialysis, prolonged mechanical ventilation, gastrointestinal complications, and acute limb ischemia.
According to Dr. David Kress, the leading study investigator and senior cardiothoracic surgeon at Aurora St. Luke’s Medical Center in Milwaukee, Wisconsin: "The clinical risk associated with HPF4 antibodies in patients who don’t have HIT syndrome is poorly understood in clinical practice. This study suggests that just having HPF4 antibodies, even without HIT or thrombocytopenia, confer a risk of adverse outcomes."
This study is the first to control for comprehensive preoperative risk factors and uses the Society of Thoracic Surgeons (STS) National Adult Cardiac Surgery Database to evaluate postoperative outcomes.
The results confirm prior studies that show 12.7 to 22 % of patients who test positive for HPF4 antibodies prior to cardiac surgery, independent of HIT, are at an increased risk for complications.
This suggests that optimal preoperative care for cardiac surgery patients should include screening for HPF4 antibody status to identify and minimize the development of HPF4 antibodies during cardiac surgery and to reduce the risk in the overall cardiac surgery patient population.