title: Influence of Body Mass Index on the Activated Clotting Time Under Weight-Based Heparin Dose.
abstract: BACKGROUND
  Activated clotting time (ACT) has been successfully applied during percutaneous coronary intervention (PCI) to monitor the extent of thrombin inhibition and anti-coagulation from unfractionated heparin (UFH) aiming to reduce the incidence of thrombotic adverse events and hemorrhagic complications. And this investigation was to explore the influence of body mass index (BMI) on ACT in patients received weight-based dose of UFH during PCI treatment.
  
  
  METHODS
  78 male patients undergoing coronary angiography or PCI treatment with a mean age of 63.86 ± 6.89 years were enrolled in this study. The patients were statistically divided into four quartiles according to their BMI. The ACT values were recorded as ACT0 , ACT5 , ACT10 , ACT30 and ACT60 , respectively. Taking the preoperative ACT0 as reference, and the differences of the other ACT values with ACT0 was indicated as ΔACTs. ACT values peaked at 5 min in 33.33% of the patients, 10 min in 51.33% of the patients and 30 min in 15.34% of the patients, respectively.
  
  
  RESULTS
  In addition, significant differences were found in overall maximum post-UFH ACT values among all BMI quartiles. UFH doses per blood volume were significantly different among the BMI quartiles, showing a positive association with BMI quartiles; further evidence revealed that the areas under the ΔACT-time curves increased gradually from quartile I to quartile IV. The proportions of ACT60 > 250 s and ACT60 > 300 s were found to be positively correlated with the increased BMI at 60 min after heparin loading.
  
  
  CONCLUSIONS
  The results of our study have shown that a standardized dosing nomogram that uses the actual body weight to calculate the heparin doses may result in UFH overdose for patients with higher BMI compared to patients with lower BMI.
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Xia
authors.initials: X
authors.lastname: Hong
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Pei-Ren
authors.initials: PR
authors.lastname: Shan
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Wei-Jian
authors.initials: WJ
authors.lastname: Huang
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Qian-Li
authors.initials: QL
authors.lastname: Zhu
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Fang-Yi
authors.initials: FY
authors.lastname: Xiao
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, P.R. China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhou
mesh_terms: D000368:Aged; D001777:Blood Coagulation / Q000187:drug effects*; D015992:Body Mass Index; D001835:Body Weight / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006493:Heparin / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D006493:Heparin
keywords: activated blotting time; body mass index; unfractionated heparin