We measured the fully carboxylated
prothrombin levels using the
Carinactivase-1 (CA-1) test and thus compared
prothrombin levels between patients having
atrial fibrillation (Af) without pacemaking and those having
sick sinus syndrome due to Af with cardiac pacemaker implantation during anticoagulation
therapy with
warfarin. Total plasma samples were assayed for the CA-1 test, the prothrombin time international normalized ratio (PT-INR) and the thrombotest (TT). This prospective randomized study was carried out on 641 samples obtained at the Fukuoka University Hospital Department of Cardiovascular Surgery between May 1997 and March 1999. The patients were divided into 2 groups consisting of: group
A; 144 patients having
sick sinus syndrome due to Af implanted with a cardiac pacemaker who were treated with
warfarin, group B; 497 patients
atrial fibrillation without pacemaking who were treated with
warfarin. The
prothrombin levels in each group were 65.5 +/- 25.2 and 76.1 +/- 47.7 micrograms/ml, respectively. The normal
prothrombin levels of group A decreased more significantly than in group B. Therefore, the PT-INR and TT were not significantly different between groups A and B. The dose of
warfarin in each group was 2.4 +/- 1.0 and 2.6 +/- 1.4 g/day, respectively. The dose of
warfarin in group A therefore decreased significantly different more than in group B. In conclusion, the normal
prothrombin levels of patients
atrial fibrillation increased more significantly than patients having
sick sinus syndrome due to Af implanted with a cardiac pacemaker.