Atrial Fibrillation

Javier E. Banchs MD, FACC, FHRS

Baylor Scott & White Health

Objectives

• Review the clinical presentations and

treatment targets in AF

• Understand modifiable risk factors in Atrial

Fibrillation (AF)

• Discuss stroke prevention strategies in AF

1

A new paradigm in Medicine

“My Apple Watch shows my heart rate is

cero during my exercise”

2

…consumer electronics meets Health Care

3

The Apple Heart Study

4

N Engl J Med 2019;381:1909-17.

The Apple Heart Study

5

N Engl J Med 2019;381:1909-17.

• 419,297 volunteers consented via iPhone

App

– 2,161 (0.52%) irregular heart rhythm

– 450 returned ECG patches

– 34% confirmed atrial fibrillation

– PPV 0.84

– 57% patients sought attention outside study

The Apple Heart Study

6

N Engl J Med 2019;381:1909-17.

Clinical presentation of AF

• Asymptomatic– Wellness monitoring

– Incidental finding

– Stroke

– Critically ill

• Symptomatic– Palpitations, tachycardia, chest discomfort,

dyspnea, syncope

– Tachycardia induced cardiomyopathy

7

Asymptomatic AF

• Diagnosis confirmation

– ECG

– Ambulatory heart rhythm monitoring

• Patient education

• Treatment

– Risk Factors Modification

8

Asymptomatic AF

• Diagnosis confirmation

– ECG

– Ambulatory heart rhythm monitoring

• Patient education

• Treatment

– Risk Factors Modification

– Additional treatment?

9

Asymptomatic AF

• Diagnosis confirmation

– ECG

– Ambulatory heart rhythm monitoring

• Patient education

• Treatment

– Risk Factors Modification

– Additional treatment (AF burden)

10

How Much AF is too Much AF?

11

Subclinical AF and Stroke

12

0 1 2 ≥ 3

NO or < 5 min

1.7% 0% 0% 25%

5 min - < 24h 1.8% 1.3% 2.4% 0%

> 24h 0% 4.4% 4.4% 33%

CHADS2 Score

AT/A

F D

ura

tio

n

568 patients followed x 1 year with PPM and history of AF

P=0.0355%

0.8%

Botto GL et al. J Cardiovasc Electrophysiol. 2009 Mar;20(3):241-8

Tachycardia Induced Cardiomyopathy

13

Natural History of Atrial Fibrillation

Guidelines for the management of atrial fibrillation (ESC)Eur Heart J. 2010 Oct;31(19):2369-429

Symptoms in AF

• Symptoms

– Tachycardia

– Irregular rhythm

– Cardiomyopathy

Treatment of AF

• Risk factors modification

• Rate control

• Rhythm control

• Stroke prevention

Pathophysiology

GENES

ENVIRONMENT

LEFT ATRIAL DILATATION / REMODELINGAUTONOMIC IMBALANCE / HUMORAL ACTIVATION

INFLAMMATION / FIBROSISAUTOMATICITY / TRIGGERED ACTIVITY - SLOW CONDUCTION

SUBSTRATEMultipleReentry

TRIGGERSPACs

Atrial TachycardiaSVT

HEART DISEASE

Risk Factors Modification

• HTN

• CAD

• Obesity

• Obstructive Sleep apnea

• Exercise

• Alcohol

• Smoking

AF Risk Factors

19

Population attributable fraction of major risk factors for atrial

fibrillation in the Atherosclerosis Risk in Communities study

Huxley RR et al. Circulation. 2011;123:1501–1508.

20

Voskoboinik A, et al. JACC 2016;68:2567-2576

Alcohol

Exercise – or lack of

21

Morseth B, et al. Eur Heart J. 2016 Aug 1; 37(29):2307-13

Smoking

22

• Women’s Health Study 20,822

HR 1.2 (1.06-1.57)

• CHARGE AF 18,556

HR 1.44 (1.20-1.72)

Everett BM, et al Eur Heart J 2013; 34: 2243–51

Alonso A, et al. J Am Heart Assoc 2013; 2: e000102

Obstructive Sleep Apnea

23

Gami AS, et al. Circulation. 2004;110:364-367

Adjusted OR and 95% CI for association between AF and OSA

Proportion and 95%

CI of patients with OSA

Obesity

Pathak RK, et al. J Am Coll Cardiol 2015;65:2159–69

46%

Pathak RK, et al. JACC 2014;64:2222-2231

Arrest AF

Treatment

• Risk factors modification

• Rate control

• Rhythm control

• Stroke prevention

Rate Control

• Prevention of tachycardia induced

cardiomyopathy

• Symptoms relief

27

Rate control interventions

• Beta blockers

• Calcium channel blockers

• Digoxin

• Amiodarone

• AV node ablation

Target Rate

Race II Trial

Van Gelder IC et al. N Engl J Med 2010;362:1363-73

614 patients

HR<80 bpm

HR<110 bpm

Treatment

• Risk factors modification

• Rate control

• Rhythm control

• Stroke prevention

Rhythm control

• Cardioversion

– TEE guided

– AC x 3 weeks

• Antiarrhythmic drugs

– Flecainide and propafenone

– Dronedarone

– Sotalol

– Dofetilide

– Amiodarone

Antiarrhythmic Drugs

32

January CT et al. J Am Col Cardiol 2014; 64:e1–76* may increase morality – (pooled data)

2014 AHA/ACC/HRS Guidelines

January CT et al. JA C C V OL . 6 4 , N O . 2 1 , 2 0 1 4 : e 1 – 7 6

Rhythm control

• Catheter based ablation

– Radiofrequency ablation

– Cryoballoon ablation

– Surgical

– Hybrid

Radiofrequency ablation

Kuck KH, et alN Engl J Med 2016;374:2235-45

Cryoballoon Ablation

Kuck KH, et alN Engl J Med 2016;374:2235-45

Cryoballoon Vs. Radiofrequency

Kuck KH, et alN Engl J Med 2016;374:2235-45

CABANACatheter Ablation Versus Antiarrhythmic Drug therapy for Atrial

Fibrillation Trial

• Randomized open label AF Ablation Vs.

Drug Therapy

• International 126 sites

• 2,204 patients

• Primary endpoint: composite of death,

stroke, bleeding, cardiac arrest

39

JAMA. 2019;321(13):1261-1274.

Cumulative risk of death, disabling stroke, serious bleeding, or cardiac

arrest (primary end point by intention-to-treat analysis)

Cumulative risk of death, disabling stroke, serious bleeding, or cardiac

arrest (primary end point) per-protocol analysis

40

JAMA. 2019;321(13):1261-1274.

Freedom from recurrence of AF following the blanking period in 1240

patients who used the study electrocardiogram event recorders

41

JAMA. 2019;321(13):1261-1274.

42

CABANACatheter Ablation Versus Antiarrhythmic Drug therapy for Atrial

Fibrillation Trial

• “On treatment”

• Primary endpoint on treatment: 7% (ABL)

Vs. 10.9% p=0.006

• 33% reduction

• 40% mortality risk reduction with ablation

(7.5% Vs 4.4%)

Treatment

• Risk factors modification

• Rate control

• Rhythm control

• Stroke prevention

Stroke Prevention

• Risk Assessment

• Anticoagulation

– Warfarin

– DOAC

• Left atrial appendage occlusion

Lyp GYH, et al. CHEST 2010; 137(2):263–272ESC Guidelines. Eur Heart J. 2010 Oct;31(19):2369-429

Risk of Thromboembolism

CHA2DS2-VASc

Heart Failure 1HTN 1Age:

65 175 2

Diabetes 1Stroke/TIA 2Vascular Dz 1Sex Fem 1

Dabigatran

Connolly SJ. et al. N Engl J Med 2009;361:1139-51

Patel M. R. Et al. ROCKET AF. N Engl J Med 2011;365:883-91

Rivaroxaban

Granger CV et al. ARISTOTLE. N Engl J Med 2011;365:981-92

Apixaban

N Engl J Med 2013;369:2093-104

ENGAGE AF-TIMI 48

Edoxaban

“Valvular” AF

• Evaluated heart valve = rheumatic or

artificial (Type I)

– Moderate-severe rheumatic Mitral stenosis

– Mechanical prosthetic valves

• Evaluated heart valve = rheumatic or

artificial (Type II)

– All others

Lip, et al. Europace (2017) 19, 1757–1758

WARFARIN

WARFARIN OR DOAC

“Valvular” AF

• Evaluated heart valve = rheumatic or

artificial (Type I)

– Moderate-severe rheumatic Mitral stenosis

– Mechanical prosthetic valves

• Evaluated heart valve = rheumatic or

artificial (Type II)

– All others

Lip, et al. Europace (2017) 19, 1757–1758

WARFARIN

WARFARIN OR DOAC

Pollack Jr et al. N Engl J Med 2015;373(6):511-20.

54

N Engl J Med 2019;380:1326-35.

Alternatives to Anticoagulation

Watchman Amplatzer(Amulet)

Lariat

Watchman

• CHA2DS2-Vasc score 3 or higher

• CHADS2 score 2 or higher

• Candidate for anticoagulation

• Reason to seek an alternative to long term

anticoagulation

• No LAA thrombus

• Favorable LAA anatomy

57

Protect AF and PREVAIL 5 years

58

J Atr Fibrillation. 2018 Dec; 11(4): 2119.

2 year follow up EWOLUTION trial

Circ Arrhythm Electrophysiol. 2019;12:e006841

No AC in 72%

Natural History of Atrial Fibrillation

Guidelines for the management of atrial fibrillation (ESC)Eur Heart J. 2010 Oct;31(19):2369-429

Conclusions

• Treatment of AF is centered on risk factors

modification, stroke prevention, rate control

and suppression of symptoms

• Direct oral anticoagulants are preferred

over warfarin for stroke prevention

Conclusions

• Left atrial appendage occlusion is not

inferior and may be superior to warfarin for

stroke prevention in patients with AF

seeking an alternative to long term AC

• Catheter based ablation and antiarrhythmic

agents could be effective in rhythm control

but recurrence rates remain high

63

Additional Slides

64

65

Clinical Trials - First Line Randomized Multicenter ABL Vs. AAD

Trial Year N AF F/U Succ.ABL

Succ.AAD

Comp.ABL

Comp.AAD

RAAFT 2005 70 PAF 12 m 87%* 34% 9% 11%

MANTRA-PAF 2012 294 PAF 24 m 13%AF 19%AF 17% 15%

RAAFT-2 2014 127 PAF 24 m 45%* 28% 9% 4.9%

Calkins H et al. Heart Rhythm 2017;14:e275–e444)

*p<0.04

66

Hakalahti A et al. Europace (2015) 17, 370–378

Clinical Trials - First Line Randomized Multicenter ABL Vs. AAD

67

Ablation Vs. Drug Therapy

Khan AR et al. Circ Arrhythm Electrophysiol. 2014;7:853-860Copyright © American Heart Association, Inc. All rights reserved.

68

CABANACatheter Ablation Versus Antiarrhythmic Drug therapy for Atrial

Fibrillation Trial

• Primary endpoint: 8 (ABL) Vs. 9.2 %

• 17% mortality or CV hosp reduction with

ablation (58.1% Vs 51.7%) p=0.001

• 47% reduction in AF recurrence p<0.0001

• 9.2% did not have ablation; 27.5%

crossover from drug to ablation

10 years follow up

Kawaji T. et al. International Journal of Cardiology 249 (2017) 204–213