2 standard population 2.02 and 1.73) [9]. There is no deﬁnite explanation for these facts, but a recent survey suggested that a higher prevalence of AF in the Portuguese population aged 40 and over, as compared to studies carried out in other countries, combined with an underutilization of VKAs, might contribute to these ﬁgures [10–12]. Furthermore, the Stroke and Atrial Fibrillation Ensemble (SAFE) II study suggested that, among patients with AF-associated stroke, underutilization of VKAs (70% of the patients had an indication for OAC, but less than 25% were anticoagulated) is frequently attributed to inappropriate reasons, such as fear of bleeding complications and low compliance [13]. Dabigatran was the ﬁrst new oral anticoagulant approved in Europe for stroke prevention in nonvalvular AF and be- came available in Portugal earlier than in most other Euro- pean countries. It seems reasonable to assume that its widespread utilization may soon become a reality, not only in hospital settings, but also in rural areas that lack laboratory facilities and particularly among clinicians previously reluc- tant in prescribing VKAs. This paper is the joint eﬀort of a panel of Portuguese experts from diﬀerent specialties and provides information on the use of dabigatran, in anticipation of the challenges that will come with increased usage. The authors discuss the management of dabigatran-associated complications and the diﬀerent clinical scenarios a clinician may encounter in patients treated with this new anticoagulant, underlining the paucity of systematic data, particularly on the management of recently reported hemorrhagic complications. Given the lack of speciﬁc clinical evidence, some of the recommen- dations below are based exclusively on the opinion of the authors and are identiﬁed as Author’s Recommendations (AR). 2. Questions 2.1. Should the Decision to Start Treatment with Dabigatran or to Switch from VKAs to Dabigatran Be Restricted to Specialists Managing Patients with Atrial Fibrillation? What Is the Role of the General Practitioners (GPs)? AF is frequent in the general population, its prevalence increases exponentially with age, and it is responsible for up to 20% of all strokes [14]. Due to the known limitations of VKAs, many patients with AF at a moderate-to-high risk of stroke, and with an indication for anticoagulation, are currently not treated [10]. For these patients dabigatran represents a new window of opportunity. As ﬁrst-line clinicians in national health systems, GPs can play a critical role not only in the diagnosis, but also in the treatment of AF. This position can be strengthened by the approval of new OACs, such as dabigatran, that has a better eﬃcacy/safety proﬁle and a broader therapeutic window [1]. The prerequisite for dabigatran prescription is not so much that the physician is a specialist or GP, but that he is competent in AF management and knowledgeable of its pharmacological treatment, dabigatran included. When a GP diagnoses AF three issues must be addressed: (1) rate and rhythm management, (2) antithrombotic management, Thrombosis (3) diagnosis of concomitant cardiac disease and, when present, appropriate therapy [14]. In terms of antithrombotic therapy, recommendations for its use should be based on the presence (or absence) of risk factors and the risk of bleeding should also be taken into account [14]. According to the 2010 European Society of Cardiology (ESC) guidelines, the new CHA2DS2-VASc stroke risk stratiﬁcation scheme may have a better predictive value when compared to the CHADS2 score [14]. As for the risk of bleeding, the HAS-BLED risk stratiﬁcation score can be used for its determination [14]. With these results in mind and with the objective of obtaining a positive clinical beneﬁt between prevention of thromboembolic events and avoidance of hemorrhagic complications, the decision to start OAC and to prescribe dabigatran or to switch from VKAs to dabigatran can be taken by any physician (AR). 2.2. How to Start Dabigatran? How to Switch from VKAs or Parenteral Anticoagulants to Dabigatran? Before starting dabigatran, creatinine clearance (CrCl) must be evaluated in all patients using the Cockcroft-Gault formula [15, 16]. In Europe, dabigatran is contraindicated in patients with severe renal failure (CrCl < 30 mL/min) [17]. In the USA, the FDA approved dabigatran 75 mg bid for patients with a creatinine clearance of 15 to 30 mL/min [2]. A complete blood count should also be performed, since anemia and thrombocytopenia increase the risk of bleeding [4]. To switch from VKAs to dabigatran, physicians should ﬁrst stop VKA and obtain an international normalized ratio (INR). If INR is below 2.0, dabigatran can be started immediately; if INR is between 2.0 and 3.0, dabigatran should be started in 2 days (AR). For patients with INR above 3.0, a further INR should be obtained after 2 days and dabigatran should be started as soon as the new INR is below 2.0, as stated above. To switch from parenteral anticoagulants to dabigatran, with intermittent therapy (low molecular weight heparin), dabigatran should be given 0 to 2 hours before the time the next dose would be due. With continuous treatment (intravenous unfractionated heparin) dabigatran should be given at the time of discontinuation [17]. When switching from a VKA to dabigatran, clinicians should be aware that the beneﬁts of dabigatran over warfarin are inﬂuenced by the eﬃciency with which the INR is controlled [18]. For all vascular events, nonhemorrhagic events and mortality, advantages of dabigatran over warfarin were greater at sites with poor INR control when compared to sites with good INR control. Nevertheless, the beneﬁts of dabigatran 150 mg bid at reducing stroke or SE, dabigatran 110 mg bid at reducing major bleeding and both doses at reducing intracranial bleeding were consistent irrespective of the center’s quality of INR control. 2.3. After Starting Dabigatran, When Should a Follow-Up Appointment Be Scheduled? Dabigatran does not require routine laboratory monitoring. Nevertheless, it is important to monitor adherence to therapy and eventual adverse events.