Abstract 3794: Systemic Hypothermia to Prevent Contrast Nephropathy: the COOL RCN Pilot Trial
Background: The development of radiocontrast nephropathy (RCN) after invasive cardiology procedures has been strongly associated with early and late mortality. Establishment of a systemic hypothermic state prior to iodinated contrast administration reduces ATP depletion and prevents ischemic cell death. We therefore performed a human pilot study of systemic hypothermia prior to cardiac catheterization in pts at high risk for RCN.
Methods: Using the Radiant Reprieve® system, hypothermia (<34 °C) was induced in 30 pts undergoing angiography or PCI with baseline creatinine clearance (CrCl) 20–50 mL/min. Shivering was suppressed with buspirone, meperidine and a warming blanket. Serum creatinine (SCr) was measured at 24, 48 and 72–96 hours. The primary endpoint was RCN defined as a rise in SCr >25% from baseline (expected rate 40%).
Results: Median age was 71 yrs; 77% were male, 50% had diabetes. Mean baseline SCr and CrCl were 2.4 ± 0.7 mg/dL and 35.2 ± 8.9 mL/min respectively. Mean contrast volume was 150 ± 65 cc, 100% low osmolar, 76% Visipaque. Mean temp achieved at first contrast dose was 33.3 ± 0.5 °C. There was no significant change in mean SCr over 96 hours (graph). RCN developed in 3 pts (10%), with absolute SCr increases of 0.9, 1.0 and 1.1 mg/dL. With follow-up complete to 30 days, no pt required dialysis or died.
Conclusions: Systemic hypothermia is a promising modality to prevent RCN in high risk pts. The pivotal COOL RCN trial (400 pts randomized to hypothermia vs. control at 35 centers) has begun recruitment.