Este documento discute el manejo de pacientes con fibrilación auricular no valvular que requieren anticoagulación. Resalta que la fibrilación auricular aumenta significativamente el riesgo de ictus y que escalas como CHA2DS2-VASc y HAS-BLED pueden cuantificar los riesgos trombótico y hemorrágico, respectivamente. Analiza los beneficios y limitaciones de los antagonistas de la vitamina K frente a los nuevos anticoagulantes orales como el rivaroxabán, concluyendo que este último demo
3. Complicaciones FA: ictus
• Factor de riesgo independiente para:
▫ Ictus isquémico:
Aumenta 5 veces el riesgo
1/6 ictus son debidos a FA (↑edad)
Más graves
Mismo riesgo en FA paroxística.
▫ Mortalidad tras el ictus:
Aumenta el riesgo de mortalidad tras ictus
4. CHA2DS2-
VASc
1-year
stroke rate
9 15.2%
8 6.7%
7 9.6%
6 9.8%
5 6.7%
4 4%
3 3.2%
2 2.2%
1 1.3%
0 0
CHA2DS2-VASc
Item Points
Previous stroke
TIA or systemic
embolism
2
Age ≥75 years 2
Congestive heart
failure*
1
Hypertension 1
Diabetes mellitus 1
Age 65–74 years 1
Female gender 1
Vascular disease 1
*Or moderate-to-severe left ventricular systolic dysfunction (left ventricular ejection fraction ≤40%)
Olesen JB et al. BMJ 2011;342:d124; Camm AJ et al. Eur Heart J 2010;31:2369–2429
Add
points
together
Beneficio
ACO
5. HAS-BLED
Clinical characteristic Points
Hypertension (systolic BP >160 mm Hg) 1
Abnormal renal or liver function 1 + 1
Stroke 1
Bleeding 1
Labile INRs 1
Elderly (age >65 years) 1
Drugs or alcohol 1 + 1
Cumulative score Range 0−9
Pisters R et al. Chest 2010;138:1093–1100
≤2Riesgo bajo
≥3 Riesgo alto
6.
7.
8.
9. Beneficio clínico neto
• Combinar riesgo embólico (RE) y riesgo hemorrágico
(RH)
• En la mayoría:
▫ Alto riesgo embólico
▫ Alto riesgo hemorrágico
▫ RE>RH
• Realmente las escalas de riesgo hemorrágico sólo
deben servir como una bandera roja a la hora de
extremar las precauciones o limitar los factores de
riesgo.
Beneficio
ACO
10. Ventajas AVK/HBPM
Gran experiencia de uso (efectos 2ª,
interacciones…)
INR para medir intensidad de anticoagulación (en
caso trombolisis o hemorragia).
Uso probado en valvulopatías
Utilizable en Insuficiencia Renal
Uso permitido en embarazo
Antídoto eficaz
Vitamina K/Plasma fresco/PCC/Factor VIIa
Protamina
11. Limitaciones AVK
Lento inicio y fin de acción.
Interacciones con dieta/fármacos.
Estrecha ventana terapeútica.
Variabilidad respuesta intra/interpaciente.
Necesidad de monitorización INR.
T. real de ACO reducido/baja adherencia.
12. Nuevas dianas
VKA VKA
Factor Inactivo
Factor activo
Transformación
Catalisis
X IX
IXa
Trombina
Xa
Fibrinogeno Fibrina
Protrombina
VIIFT VIIa
Formación trombo
Inicio
Propagación VKA
Inhibidores Directos Factor IIa
Dabigatran
II
IIa
Piccini JP et al. Curr Opin Cardiol 2010;25:312–320; Spyropoulos AC et al. Expert Opin Investig Drugs 2007;16:431–440
Inhibidores Directos Factor Xa
Rivaroxaban
Apixaban
Edoxaban
Betrixaban
Nuevo VKA
Tecarfarina
13.
14.
15. Características ideales
• Dosis fijas sencillas
• Rapidez de inicio/fin de acción
• No interacciones dieta/fármacos
• Farmacocinética/anticoagulación predecible
• No necesidad de monitorización
• Reversible (al suspender + antídoto)
Mejor calidad de vida
de los pacientes
Menos costes
(menos visitas
médicas)
Mejor cumplimiento
Mejora de la eficacia y seguridad
16. Estudios pivotales NACOs FA
• RE-LY (Randomized Evaluation of Long Term
Anticoagulation Therapy)
• Dabigatran 150 mg BID; Dabigatran 110 mg BID
Dabigatran1
•ROCKET-AF (Rivaroxaban Once-Daily Oral Direct Factor
Xa Inhibition Compared with Vitamin K Antagonism for
Prevention of Stroke and Embolism Trial in Atrial
Fibrillation)
• Rivaroxaban 20 mg QD
Rivaroxaban2
• ARISTOTLE (Apixaban for Reduction in Stroke and
Other Thromboembolic Events in Atrial Fibrillation)
• Apixaban 5 mg BID
Apixaban3
•ENGAGE AF-TIMI 48 (Effective Anticoagulation with
Factor Xa Next Generation in Atrial Fibrillation-
Thrombolysis In Myocardial Infarction)
•Edoxaban 60 mg QD regimen; Edoxaban 30 mg QD
regimen
Edoxaban4
1. Connolly SJ et al. N Engl J Med 2009;361:1139-1151;
2. Patel MR et al. N Engl J Med 2011;365:883-891;
3. Granger CB et al. N Engl J Med 2011;365:981-992;
4. Giugliano RP et al. N Engl J Med 2013;369:2093-
2104.
17. Rivaroxaban
Inhibidor directo, específico
y competitivo del Factor
Xa.
Tanto libre como unido a
fibrina en el trombo.
No efecto en la
antiagregación inducida
por la trombina.
Dosis única diaria
Roehrig S et al. J Med Chem 2005;48:5900–5908; Perzborn E et al. J Thromb Haemost 2005;3:514–521;
Perzborn E et al. Nat Rev Drug Discov 2011;10:61–75
18. Rivaroxaban – PK+PD
• Muy buena biodisponibilidad oral del 66% (cercana
al 100% con alimentos)
• Unión a proteínas 92-95%
• Vida media: 5-9 h /Pico dosis:3-4 h
• Metabolismo hepático (66%)
▫ Citocromo CYP3A4
▫ No metabolitos activos
▫ No ajuste dosis en hepatopatías
• Eliminación hepatobiliar/renal.
▫ Ajuste de dosis en insuficiencia renal
• No ≠ edad, sexo o peso.
20. ROCKET AF: Conclusiones
Basado en el criterio principal de valoración de la eficacia preespecificado:
Una pauta de dosis fija una vez al día de rivaroxabán fue no inferior a warfarina en
la prevención de ictus o embolia sistémica no cerebral.
Rivaroxabán fue superior a warfarina mientras los pacientes estaban tomando el
medicamento del estudio.
El análisis de sensibilidad en la población ITT con los datos hasta la notificación del
centro mostró un beneficio para rivaroxabán, aunque no alcanzó superioridad.
Seguridad:
Tasas similares de hemorragias y acontecimientos adversos.
Aumento de las hemorragias digestivas pero un número significativamente menor
de hemorragias intracraneales, hemorragias de órganos críticos y menos
hemorragias mortales con rivaroxabán.
Conclusión:
Rivaroxabán, una vez aprobado para esta indicación, es una alternativa demostrada
de administración una vez al día frente a warfarina con eficacia no inferior en toda la
población y eficacia superior "durante el tratamiento", hemorragias totales similares
y menos hemorragias intracraneales y mortales.
21. Resumen: ROCKET AF vs otros estudios
ROCKET AF es diferente de otros estudios de nuevos anticoagulantes
orales en prevención del ictus en FA finalizados recientemente o
actualmente en marcha
Diferente población de pacientes:
– Mayor proporción de pacientes con necesidad real de anticoagulación en
comparación con otros estudios
Diferencia en cuanto al diseño doble ciego vs RE-LY:
– ROCKET AF: estudio doble ciego, doble enmascaramiento
– RE-LY: estudio abierto con administración abierta de warfarina y ciega para
las dos dosis de dabigatran
Diferente comparador vs AVERROES:
– ROCKET AF: comparación con el tratamiento estándar (AVK)
– AVERROES: comparación frente AAS
Diferente esquema de dosificación vs RE-LY, AVERROES y ARISTOTLE:
– ROCKET AF: una vez al día
– RE-LY (dabigatran), AVERROES y ARISTOTLE (apixaban): dos veces día
Diferent criterio de valoración principal de seguridad:
– ROCKET AF: combinación de hemorragia mayor y no mayor clínicamente
relevante
– Otros estudios: solo hemorragia mayor 22
22. Resumen: similitudes entre estudios
Consistencia en las expectativas de no inferioridad en
el criterio de valoración principal de eficacia vs AVK en
todos los estudios
Uso de criterios de valoración similares:
Misma variable principal de eficacia en todos los
estudios (combinación de ictus y embolismo
sistémico)
Variables secundarias similares en los distintos
estudios
23
23. Why is adherence to anticoagulation therapy important?
VKAs are only effective when anticoagulation
effect is kept within the therapeutic range
Novel OACs (rivaroxaban, dabigatran, apixaban):
Short duration of effect (vs warfarin) – fixed daily
dosing to maintain protection against stroke
Strict therapy adherence is critical to avoid stroke
and improve patient outcomes
1. Cramer et al, Value Health 2008;11:44–47; 2. Heidbuchel et al, Europace 2013;15:625–651
24. Summary
Strict adherence to OAC therapy and long-term persistence is
critical to avoid stroke and improve outcomes in patients with
AF
There are many strategies to improve adherence, including
patient education and better patient–provider channels of
communication
Once-daily dosing has a number of advantages over multiple
daily dose regimens, including improving adherence
There is clear evidence that patients prefer once-daily dosing
Top 5
25. Improved patient–physician communication
Opening channels of communication is essential
Communication methods and accessibility of physician or
pharmacist, e.g. contact details
Important things to address
with patients:
Timing of doses
Missed dose
Worries/concerns
Any bleeding events
Patient preference towards other treatment options available
Heidbuchel et al, Europace 2013;15:625–651
26. Simplified, individualized therapy:
Patient Personalised System
Individualizing therapy:
‘fitting into the patient’s life’
od dosing
Timing of dose (fit into daily routine)
Habit reinforcement
Family involvement
Follow-up and patient cards
Technology to enhance adherence
Blister/medication packs/pill boxes
with days of the week; smartphone
apps/message alerts/reminders
Heidbuchel et al, Europace 2013;15:625–651
Notes de l'éditeur
CHADS2 is useful but has some limitations
Some risk factors are not recognized; stroke risk may be underestimated
Age is not a binary risk factor
High proportion of patients categorized at intermediate risk
CHA2DS2-VASc
More reliably identifies patient’s risk
Only small proportion categorized as intermediate risk
Simplifies (dichotomizes) selection of patients for anticoagulation
Removes uncertainty regarding the optimal form of thromboprophylaxis
Trials of newer OACs for stroke prevention in patients with AF
ROCKET AF is different from other recently completed and ongoing trials of new OACs for stroke prevention in AF
There are several differences including:
Patient population
Blinding
Comparator
Dosing schedule
Principal safety endpoint
Definition of endpoints
References
Patel MR et al. N Engl J Med 2011;365:883–891.
Connolly SJ et al. N Engl J Med 2009;361:1139–1151.
http://www.bms.com/news/press_releases/pages/default.aspx?RSSLink=http://www.businesswire.com/news/bms/20110622006923/en&t=634444126192849398.
It is critical to ensure patients understand why adherence to anticoagulation therapy is important. This, combined with knowledge of the disease, the risk of future negative outcomes (such as stroke) and how anticoagulant therapy works should help to improve adherence and outcomes.
In order for a drug to be effective, the anticoagulation effect is kept within the therapeutic range; this is maintained through dosing regimens
Novel OACs (rivaroxaban, dabigatran and apixaban) have a shorter duration of effect than VKAs (warfarin); therefore, daily dosing is required to maintain therapeutic levels and prevent stroke
Consequently, strict therapy adherence is vital to ensure effective concentrations of the drug are maintained in the blood to prevent stroke and improve patient outcomes
Abbreviation
OAC, oral anticoagulant
This slide summarizes the main points covered in this presentation:
Strict adherence to anticoagulant therapy is critical to avoid stroke and improve outcomes in patients with AF
There are many strategies to improve adherence, including patient education and better patient–provider channels of communication
Providing simple, tailored, long-term therapy also represents a key aspect in improving patient adherence, e.g. fixed once-daily dosing that fits into most patients’ lives easily
Abbreviation
AF, atrial fibrillation
Patients need to know how to use OACs effectively and safely in clinical practice and what to do in certain situations (such as experiencing a bleeding event). Improved patient–physician communication is essential to achieve this.
Opening channels of communication will make the physician more accessible to the patient, allowing the patient to contact the physician when they have any questions/queries relating to their anticoagulation therapy
Discussing a patient’s questions/queries will help to reassure the patient, improve their understanding of anticoagulation therapy, emphasize the importance of staying on anticoagulation therapy and facilitate adherence
Discussing a patient’s questions/queries will also allow the physician to effectively monitor the patient; important things to address include: timing of dose, missed dose, worries/concerns, bleeding events and patient preference towards other treatment options available
In order to discourage anticoagulant therapy discontinuation, a patient should be made aware that there are several anticoagulation therapy options available and if they are unhappy with their current anticoagulation therapy, another one may be more suitable
This will encourage the patient to raise the question of an alternative therapy with the physician if they are unhappy with their current therapy, as opposed to discontinuing anticoagulant therapy, which would increase their risk of AF-related stroke
Abbreviations
AF, atrial fibrillation; OAC, oral anticoagulant
Reference
Heidbuchel et al. Europace 2013;15:625–651
Simplified, individualized therapy will help fit the therapy into the patient’s life, making being on anticoagulation therapy easier
Once-daily dosing and fitting the timing of dose into the patient’s daily routine will facilitate convenience and help patients remember to take the drug
Habit reinforcement and family members’/caregivers’ involvement will help patients to remember to take the drug according to the dosing regimen
Follow-up and patient cards will help patients remember to take the drug and actively monitor themselves; these methods will also provide opportunities for further patient education and improved patient–physician communication, which helps to emphasize the importance of and improve strict adherence to anticoagulation therapy (discussed on earlier slides)
The use of technology (e.g. smartphone apps/message alerts/reminders) to enhance adherence will prompt and help the patient remember to take the drug according to the dosing regimen by tracking their medication (blister/medication packs/smartphone apps)
Abbreviation
od, once daily
Reference
Heidbuchel et al. Europace 2013;15:625–651