Impact of activated clotting time guided heparin administration on bleeding events after trans-femoral transcatheter aortic valve implantation

Abstract

Aim: Bleeding following Transcatheter Aortic Valve Implantation (TAVI) still remains a frequent and potentially serious complication, being associated with an unfavorable prognosis. Adjusted heparin dose administration may reduce the risk of potential overdosing in this frail population. Therefore, the aim of this study is to evaluate the impact of Activated Clotting Time (ACT)-guided heparin administration on bleeding occurrence after trans-femoral (TF) TAVI. Methods and results: From November 2007 to June 2012, all patients with symptomatic severe aortic stenosis underwent to TF-TAVI in our center were analyzed. Intra-procedural heparin administration was performed upon operator discretion into two modalities: according to body weight (non ACT-guided) or baseline ACT (ACT-guided). The primary study objective was 30-day major bleeding occurrence as defined by the Valve Academic Research Consortium (VARC) criteria. Secondary objectives were, life-threatening, minor and any bleeding, vascular complications, acute kidney failure, myocardial infarction, stroke, all-cause and cardiovascular mortality at 30-day according to VARC. A total of 362 patients undergoing to TF-TAVI: 174 in ACT guided vs. 188 patients in non ACT-guided group. No statistically significant differences in clinical and procedural characteristics were observed between study groups. Among the entire population, major bleeding occurred in 76 (21.0%) patients. In the ACT-guided group a significant lower occurrence of major bleeding was observed (7.5% vs. 33.5%, p <0.001). In addition, a lower rate of life-threatening (12.1% vs. 20.2%, p=0.04) and any bleeding (25.9% vs. 64.9%, p <0.001) was observed in ACT-guided group. Conversely, no differences were noted in the other secondary study objectives. After adjustment for baseline confounders, the absence of ACT guidance [OR 5.9, 95% CI (2.8-12.5), p< 0.001] and baseline estimated glomerular filtration rate [OR 0.98, 95% CI (0.97-0.99), p=0.04] were the only predictors of 30-day major bleeding. Moreover, after multivariate adjustment for potential confounders ACT-guided propensity, absence of ACT guidance was identified as an independent predictor of major bleeding at 30 days [OR 6.4, 95% CI (2.3-17.9), p< 0.001]. Conclusions: In our experience, heparin dose adjustment using ACT-guided strategy has shown to reduce 30-day major, life threatening and any bleeding in TF-TAVI procedures. This strategy might be a useful tool in reducing bleeding in this high-risk population.