Abstract
OBJECTIVE: Acute renal failure after valve surgery carries significant morbidity and mortality. Preoperative cardiac catheterization is the standard of care. For convenience, catheterization just before surgery is simplest for patients. However, it is not known if this timing of radiocontrast administration significantly affects renal function. We hypothesized that preoperative cardiac catheterization within 24 hours of valve surgery is associated with the development of acute renal failure. METHODS: A retrospective case-control study was performed of all patients undergoing valve surgery between 2003 and 2008 at the University of Virginia. Patients with preoperative renal dysfunction were excluded. Patients with postoperative acute renal failure were matched to those without acute renal failure according to age, gender, year of surgery, New York Heart Association functional class, elective status, concomitant coronary artery bypass grafting, and type of valve procedure. A logistic regression model examined the effects of perioperative risk factors on the development of acute renal failure. RESULTS: Of 1287 patients undergoing valve surgery, 61 with acute renal failure were matched to 136 without acute renal failure. Cardiac catheterization within 24 hours of surgery was significantly greater in patients with acute renal failure (31.2% vs 8.8%, P = .013). The risk of acute renal failure was more than 5 times higher for patients undergoing catheterization within 24 hours of surgery (odds ratio, 5.3; P = .004). The number of postoperative vasopressors was significantly associated with acute renal failure (odds ratio, 1.7; P = .007). CONCLUSIONS: Although catheterization is often performed for patient convenience, catheterization within 24 hours of valve surgery is significantly associated with the development of acute renal failure. Current practices should be adjusted to ensure that more than 24 hours have passed from the time of cardiac catheterization to valve surgery in elective settings.