Blood Coagulation – ABC CARDIOL

IJCS

Original Article

Atrial Fibrillation and Use of Rivaroxaban: Performance of the Prothrombin Time / INR as a Function of Time After Blood Collection

Rita Carolina Figueiredo Duarte et al. Priscila Samara Sérgio Moreira Cláudia Natália Ferreira Estevão Lanna Figueiredo … Eduardo Sternick Francisco Rezende Silveira Luan Carlos Vieira Alves Ana Paula Lucas Mota Edna Afonso Reis Maria das Graças Carvalho Helton José dos Reis

Abstract

Background

Traditionally, the most effective therapy in the prevention of stroke in patients with atrial fibrillation (AF) has been oral anticoagulation with vitamin K inhibitors, particularly warfarin, whose disadvantages and adverse effects have led to their replacement by “direct oral anticoagulants”, as factor X inhibitor.

Objectives

This study aimed to conduct a brief approach on atrial fibrillation (AF) and use of Rivaroxaban, and to comparatively evaluate the prothrombin time / International Normalized Ratio (PT/INR) in patients with AF in use of this oral anticoagulant, depending on the time elapsed between the last administration of the drug and the time of blood sample venipuncture.

Methods

We evaluated 34 patients with AF in use of Rivaroxaban by using PT / INR, distributed into a subgroup with blood collection time ≤ 12 hours (n = 7) and > 12 hours after the last drug intake (n = 27). Mann-Whitney test was used to compare the groups and p < 0.05 was considered significant.

Results

An analysis as a function of time between the Rivaroxaban intake and blood collection, revealed that PT / INR suffers the greatest effect up to 12 hours after ingestion of the drug, dropping to levels close to normal in subsequent hours before the next dose.

Conclusion

We concluded that, in contrast to warfarin, the knowledge of the time interval between drug intake and blood collection from patients taking Rivaroxaban is essential to properly interpret a laboratory test to assess hemostasis, particularly PT and its derivatives. Int J Cardiovasc Sci. 2020; [online].ahead print, PP.0-0

Ler artigo completo

IJCS

Editorial

Is Bovine Heparin, an Old Fellow, a Safe Anticoagulation Approach during Extracorporeal Circulation Inside the Cardiac Operating Room?

Ivis Levy Fernandes Martins et al. Christianne Bretas Vieira Scaramello

Antithrombotic agents include anticoagulants, antiplatelet and fibrinolytic drugs. They are prescribed in several situations related to hemostasis disturbances that favor thrombi formation. Since bleeding is a common adverse effect of these drugs, a cost-benefit analysis of antithrombotic therapy prior to surgery should be performed. In order to consider the preoperative therapy for patients undergoing cardiac surgery, the risk of thrombosis must outweigh the risk of bleeding. Nonetheless, the literature has reported the use of anticoagulant therapy with unfractionated heparin (UFH) during extracorporeal circulation (ECC) inside and outside the cardiac operating room.^–

The development of the heart-lung machine made ECC possible. Therefore, heart surgery became a routine practice. The literature describes that complications related to ECC have diminished due to modern monitoring, highly trained staff, special cannulation methods, as well as the latest advances in techniques. However, some authors suggest that guidelines based on more researches would improve the safety of this procedure. During cardiac surgery, ECC preserves the functional characteristics of the heart, provides a clean surgical environment and offers safety to the team.

[…]