1017-71 Patient-Specific Heparin Dosing During Angioplasty

The risk of ischemic events and bleeding complications during angioplasty is related to the intensity of heparin anticoagulation as monitored by the activated clotting time (ACT). Data on patient characteristics that affect the dosing of heparin during angioplasty to achieve a desired target ACT is limited. The Hemochron ACT was measured 10 minutes after a heparin bolus in 438 non-emergency angioplasty patients. The influence of heparin dose, patient age, weight. gender, presenting diagnosis, and pre-procedural continuous intravenous heparin use on the intensity of anticoagulation achieved were examined with univariate followed by stepwise multivariate regression analysis. Univariate Multivariate critical value p-value critical value p-value Age 0.034 ns Weight -2.15 0.033 -2925 <0.001 Female Gender 1.21 0.34 Unstable Angina -2.04 0.043 -0.069 ns Pre-procedural IV Heparin -538 <0.001 -2.39 0023 Heparin Dose 635 <0.001 8.95 <0.001 Full-size table Table options View in workspace Download as CSV Conclusions Patient weight, pre-procedural IV heparin therapy, and heparin dose were significant independent predictors of the ACT achieved, Preprocedural intravenous heparin significantly increased the heparin dose required to achieve the target ACT, suggesting the development of tolerance to heparin. Similarly, patients with unstable angina required significantly more heparin to achieve the target ACT Recognition of these factors allows patient-specific heparin dosing during angioplasty. A nomogram for patients receiving pre-procedural heparin therapy, for example, shows the relationship between patient weight. heparin dose, and the expected target ACT. Figure options Download full-size image Download high-quality image (66 K) Download as PowerPoint slide