[Comparison of the prothrombin levels between the patients with atrial fibrillation and patients with cardiac pacemaker implantation due to sick sinus syndrome during anticoagulation therapy with warfarin].

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.