Abstract 4693: The Impact of Baseline Renal Dysfunction on Clinical Outcomes After Primary PCI for ST-Elevation Myocardial Infarction in a Regionalized Primary PCI Program
Background and Objectives: The impact of baseline creatinine clearance (CrCl) on clinical outcomes in patients (pts) treated within the context of regionalized primary percutaneous coronary intervention (PCI) programs, has not been well studied. The use of reno-protective measures is also not well known in such programs.
Methods: This study evaluated 1056 consecutive pts referred for primary PCI between May 1, 2005 and April 30, 2008 in Ottawa, Canada after implementation of an integrated metropolitan area approach in which all pts with ST-segment elevation myocardial infarction (STEMI) are transferred to a cardiac center for primary PCI. The purpose was to evaluate in-hospital outcomes in pts with renal dysfunction (CrCl of <60 ml/min, n=296) compared to those with normal renal function (CrCl ≥60ml/min, n=760).
Results: Patients with renal dysfunction were more likely to be female (54 vs 19%, p<0.0001), older (73±11 vs.56±11, p<0.0001), and have multivessel disease (71 vs. 52% p<0.0001). Median door-to-balloon time was slightly longer in the renal dysfunction group (109 vs. 105 min, p<0.0001). Following PCI, fewer pts with renal dysfunction achieved TIMI 3 flow (89 vs. 94 % p<0.006). The volume of contrast used for catheterization was lower in pts with renal dysfunction (201±75 vs. 223±72, p<0.0001). In-hospital mortality was higher in pts with renal dysfunction (12.5% vs. 2.0%, p<0.0001). TIMI major and minor bleeding occurred more frequently (13.5 vs. 6.6%, p=0.0003 and 15.7 vs. 9.5%, p=0.004, respectively). Although N-acetylcysteine (NAC) was more frequently prescribed to pts with renal dysfunction (38% vs. 11% p<0.0001), de novo dialysis was more frequently needed in these pts (4.1 vs. 0.4% p<0.0001). After adjusting for baseline variables, CrCl <60 ml/min remained an independent predictor of in-hospital mortality (p<0.0001).
Conclusion: In pts referred for primary PCI, renal dysfunction identified a population that remains at increased risk of in-hospital complications, including death. We found that the proportion of pts with renal dysfunction who received NAC was low. Future studies may help determine if more aggressive measures for reno-protection and bleeding prevention can reduce unfavourable outcomes in this population.