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Jennings LK, Jacoski MV, White MM. The pharmacodynamics of parenteral glycoprotein IIb/IIIa inhibitors. J Interv Cardiol 2002;15:45–60. 20. Kleiman NS, Raizner AE, Jordan R, Wang AL, Norton D, Mace KF, Joshi A, Coller BS, Weisman HF. Differential inhibition of platelet aggregation induced by adenosine diphosphate or a thrombin receptor-activating peptide in patients treated with bolus chimeric 7E3 Fab: implications for inhibition of the internal pool of GPIIb/IIIa receptors. J Am Coll Cardiol 1995;26:1665–1671. Comparison of Treatment Outcomes in Patients >80 Years Undergoing Transradial Versus Transfemoral Coronary Intervention W. Peter Klinke, MD, J. David Hilton, MD, Rebecca N. Warburton, PhD, William P. Warburton, PhD, and Ren P. Tan, MD We assessed the effect of transradial access (vs trans- femoral access) for percutaneous coronary interven- tion on postprocedure length of stay and patient out- comes (in-hospital complications and all-cause and cardiac death at 6 and 12 months) in 225 elderly patients (>80 years old). Raw differences between transradial and transfemoral accesses were com- pared, and 3 forms of propensity score analysis were used to determine the true effect of transradial access. After matching to adjust for baseline differences in patient characteristics, remaining differences in out- comes and postprocedure length of stay were small and not statistically significant at the 95% level, but a decrease in postprocedural length of stay of nearly 1 day was observed and likely was not due to chance. Transradial access in patients >80 years old undergoing percutaneous coronary intervention should be preferred due to equivalent success rate and safety and likely reduction in postprocedural hospitalization. 2004 by Excerpta Medica, Inc. (Am J Cardiol 2004;93:1282–1285) P ercutaneous coronary intervention (PCI) is in- creasingly used in elderly patients with coronary artery disease. The procedure is routinely performed according to standard methods (i.e., through the fem- From the Victoria Heart Institute Foundation and the School of Public Administration, University of Victoria, Victoria, British Columbia, Can- ada; and the Department of Finance and Management Science, School of Business, University of Alberta, Edmonton, Alberta, Canada. Dr. Klinke’s address is: Victoria Heart Institute Foundation, 315-1900 Richmond Avenue, Victoria, British Columbia V8R 4R2, Canada. E-mail: peterklinke@vhif.org. Manuscript received December 1, 2003; revised manuscript received and accepted February 5, 2004. 1282 ©2004 by Excerpta Medica, Inc. All rights reserved. 0002-9149/04/$–see front matter The American Journal of Cardiology Vol. 93 May 15, 2004 doi:10.1016/j.amjcard.2004.02.015