Atrial Fibrillation. Ivan Anderson, MD RIHVH Cardiology

Transcription

1 Atrial Fibrillation Ivan Anderson, MD RIHVH Cardiology

2 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

3 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

4 General Approach to Narrow QRS Tachycardia Ref: Braunwald Textboold of Cardiovascular Medicine

5 QRS complexes x 6 (10 second strip) = rate (bpm) 29 x 6 = 174 bpm

6 Atrial Fibrillation Is a supraventricular tachycardia marked by an irregularly irregular ventricular rhythm Mechanism is less clearly defined compared to other SVT, but generally: 1. Automatic triggered microrenetrant foci, called drivers, fire at rapid rates 2. Multiple reentry circuits meander through the atrial annhiliting and reforming waves pertuating atrial fibrillation

7 Mechanisms Mechanism 1 Mechanism 2

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9 Meta Analysis of Direct Oral Anticoagulants in Valvular Heart Disease (not Mitral Stenosis) Circulation. 2017;135:

10 Craig T. January et al. JACC 2014;64:

11 Atrial Flutter Treated Essentially the Same as Atrial Fibrillation

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13 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

14 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

15 Rhythm Control Most often initiated with symptomatic atrial fibrillation Preferred strategy with decompensated CHF or if rate control is ineffective No mortality benefit Associated with increased hospitalizations

16 Rate Versus Rhythm Control For Atrial Fibrillation Van Gelder IC et al. N Engl J Med 2002;347:

17 Cumulative Mortality from Any Cause in the Rhythm-Control Group and the Rate-Control Group. The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) Investigators. N Engl J Med 2002;347:

18 Rhythm Control Algorithm Craig T. January et al. JACC 2014;64:

19 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

20 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

21 Rate Control: How Fast is Too Fast? Resting HR < 110 bpm if normal LVEF and no symptoms, otherwise Resting HR < 80 bpm Exercise heart rate < 110% age-predicted maximum heart rate, less if symptomatic Many cardiologists will use HR < 140 bpm

22 From the Guidelines (Class 1) Control of the ventricular rate using a beta blocker or nondihydropyridine calcium channel antagonist is recommended for patients with paroxysmal, persistent, or permanent AF In patients who experience AF-related symptoms during activity, the adequacy of heart rate control should be assessed during exertion, adjusting pharmacological treatment as necessary to keep the ventricular rate within the physiological range (Expert opinion, no data cited)

23 How Fast is Too Fast (Class IIa & IIb) A heart rate control (resting heart rate <80 bpm) strategy is reasonable for symptomatic management of AF A lenient rate-control strategy (resting heart rate <110 bpm) may be reasonable as long as patients remain asymptomatic and LV systolic function is preserved

24 RACE II Trial Outcome Primary Outcome: death, hospitalization for CHF, stroke, embolism, bleeding, lifethreatening arrhythmia Van Gelder IC et al. N Engl J Med 2010;362:

25 Medications for Rate Control Craig T. January et al. JACC 2014;64:

26 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation CHADS2VASc score HASBLED

27 Outline Definition and Pathophysiology Rate versus rhythm control Rate control thresholds (how much is enough) Anti-coagulation!!!! CHADS2VASc score HASBLED

28 Strokes with Atrial Fibrillation: More Deadly, More Frequent Lower Survival Higher Recurrence Lin H et al. Stroke. 1996;27:

29 Anti-Coagulation is NOT Based on Classificaiton of Atrial Fibrillation Selection of antithrombotic therapy should be based on the risk of thromboembolism irrespective of whether the AF pattern is paroxysmal, persistent, or permanent (Class 1, level of evidence B) Craig T. January et al. JACC 2014;64:

30 Rhythm Control Does NOT Reduce Risk of Stroke Stroke. 2007;38[part 2]:

31 Anticoagulants > Anti-Platelet Craig T. January et al. JACC 2014;64:

32 Active A Trial Randomized control trial of Aspirin versus Aspirin + Plavix for stroke prevention clopidogrel plus aspirin reduced the risk of stroke by 28% increased the risk of major extracranial hemorrhage by 51% increased the risk of major intracranial hemorrhage by 87%

33 Strokes in the Active A trial (ASA v ASA+Plavix) The ACTIVE Investigators. N Engl J Med 2009;360:

34 Bleeding in the Active A trial (ASA v ASA+Plavix) The ACTIVE Investigators. N Engl J Med 2009;360:

35 Craig T. January et al. JACC 2014;64: Stroke Risk: CHAD 2 -VASc

36 Chest Nov;138(5): HAS-BLED Calculator

37 Falls Not part of the HAS-BLED score or most major risk calculators Infrequently lead to major bleeding May be a risk if hospitalized for mechanical fall

38 The ATRIA Hemorrhage Risk Prediction Score J Am Coll Cardiol 2011;58:

39 Dosing

40 Questions