Transcript Atrial_Fib_lecture

Atrial Fibrillation
t
• 1874 Alfred Vulpian- ‘Fremissement fibrillaire’
• 1876 Carl Nothnagel- ‘Delerium Cordis’
1906- Einthoven- 1st EKG of afib
1909- Rothberger,Winterberg& Lewis- correlation between
EKG and pulse
• Atrial Fibrillation– Absent ‘P’ waves
– Irregular atrial activity- ‘F’ waves
• Variable- amplitude, duration and
morphology
– Resultant irregular ventricular response
– Impostures- atrial flutter and MAT
Classification
• First detected- single documented episode
• Recurrent- 2 or more episodes
• Paroxysmal- Spontaneous conversion
(usually <7 days)
• Persistent- episodes are sustained (often
>7 days)
• Permanent/Chronic- persistent (typically >
1year)
Etiologies
• Valvular Heart Disease- esp. Mitral
• Non valvular and Secondary causes
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Cardiomyopathies (IDCM/NIDCM)
Hypertension
Post-CABG/Post operative state
Toxin- Thyrotoxicosis, ETOH
Pulmonary embolus/COPD
Hypoxia/Acidemia
Sinus Node dysfunction
Congenital Heart disease- WPW, ASD
• Lone Atrial Fibrillation
– <12% without identifiable cause
– Age <60
Conditions Allied with AF
Prevalence of Diagnosed Atrial Fibrillation Stratified by Age
and Sex
Go, A. S. et al. JAMA 2001;285:2370-2375.
In General- <1% of Population < 60 yrs
>6-8% of Population >80 yrs
Copyright restrictions may apply.
Projected Number of Adults With Atrial Fibrillation in the
United States Between 1995 and 2050
Go, A. S. et al. JAMA 2001;285:2370-2375.
Copyright restrictions may apply.
Concerns
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Thromboembolism
Mortality
Cardiomyopathy and CHF
As well as
– Known Knowns
– Known Unknowns
– Unknown Unknowns
Relative risk of stroke and mortality in patients with AF
compared with patients without AF
Fuster, V. et al. Circulation 2001;104:2118-2150
Risk of CV ~5% per year with risk factors
Annual CVA risk 23.5% for those aged 80 to 89 years
Copyright ©2001 American Heart Association
Kaplan-Meier curves describing survival in 46 984 postcoronary bypass surgery patients at the Cleveland Clinic
from 1972 to 2000
Verma, A. et al. Circulation 2005;112:1214-1222
Copyright ©2005 American Heart Association
AF and CVA Risk Factors
• CHADS2
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Hypertension- even a history thereof =1
Diabetes =1
Congestive heart failure =1
Age >75 years
Prior TIA/CVA = 2
• Others
– Prior MI
– Echo data- LV dysfunction (EF<35-40%) , Left atrial
enlargement
– Some argue age >60 or 65
BF Gage et al. JAMA 2001 285: 2864-2870.
Krahn AD et al. Am J Med. 1995;98:476-84 .
Atrial Fibrillations Investigators. Arch Intern Med. 1998;158:1316-20.
Risk for CVA: CHADS2
Score CVA risk/Yr
BF Gage et al. JAMA 2001 285: 2864-2870.
0
1.9%
1
2.8%
2
4.0%
3
5.9%
4
8.5%
5
12.5%
6
18.2%
AF and Cardiomyopathy
• Rawles
-↓C.O. with HR>90
• Tachycardia-induced Cardiomyopathy- may
occur with heart rates ≥ 105-110 BPM over 10-14
days
(Br Heart J 1990;63:157-61)
– Reversible with proper rate control
– Symptoms vary between patients
• Rate Control
– AFFIRM
• Resting HR ≤ 80 BPM
• 24 Hour Holter- Avg HR ≤ 100 BPM and no HR > 110% MTHR
• HR ≤ 110 BPM during 6 minute walk test
Shinbane et al. J Am Coll Cardiol 1997;29:709-15.
NHLBI AFFIRM investigators Am J. Cardiol 1997;79:1198-1202
AF in CHF: Prognostic Implications
V-HeFT
no effect
of AF
V HeFT found
no effect
of on
Sinus Rhythm
AF
AF on survival
mortality
60
Mortality (percent)
50
40
30
p=NS
p=NS
20
10
0
Middlekauf
Carson
Dries
Mahoney
Crijns
Mathew
…but SOLVD found RR 1.34, p=0.002 (Cox) Framingham HR for death 1.6
in males; 2.7 females (Cox)
Prevalence of AF and CHF
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80% in “dropsy”
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Mackenzie J. The
Oxford medicine,
1920:387-492.
Clinical Trial data
15-30% AF,
higher with worse
NYHA
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Ehrlich, Nattel, and
Hohnloser, JCE 2002
13: 399-405
AF and CHF- in sum
• AF and CHF appear to co-promote
• While treatment of LV dysfunction
prevents AF, converse not clear (except in
poorly rate-controlled subjects)
• Clinical trial data highly desirable
– AF-CHF
– Randomized study of non-pharmacologic treatment in
subjects with LV dysfunction
Circulation. 2008;118:S_827
Prevention of CHF by treatment
of AF
• Ablate and pace
– Uncontrolled studies show improvements in
LV function
– Controlled study- improved dyspnea and
exercise tolerance but not LV function
• Circulation 1998;98:953-960
• Mayo experience- does not alter prognosis
– NEJM 344:1043-1051
• Bi-V might be better
– Eur Heart Journal 2002 23: 1780-1787
Can We fix it?
• Management Strategies
– Rate Control
• Pharmacologic
• Non-Pharmacologic
– Rhythm Control
• Anti-arrhythmics
• Surgical ‘correction’
• Percutaneous ‘correction’
– Prevention
Rate vs. Rhythm
-No significant difference in mortality
-Anticogulation is essential regardless of strategy
Fuster et al. JACC.2006;48(4):e149-246
Pharmacological management of patients with newly
discovered AF
Assess for underlying disease:
Echocardiogram
Ischemic Heart diesase
Endocrine disease
OSA
CVA Risk Stratify
Fuster, V. et al. Circulation 2001;104:2118-2150
Rate Control Strategy
• AV nodal blocking Agents
– Beta-receptor antagonists
– Non-dihydropyridine Calcium channel
blockers
– Digoxin-indirect via vagal effects
• Ablate and Pace
Rate control strategery
Dig-βb
Farshi et al. JACC 1999; 33(2): 304-310
Mayo Ablate and pace experience
NEJM 344:1043-1051
Rhythm Control Simplified
Fuster et al. JACC.2006;48:854-906
Arrhythmia-free survival after electrical cardioversion in
patients with persistent atrial fibrillation
DCC- >87%
successful in
most patients
Only 25-35% of
patients will be in
sinus rhythm at
one year
Fuster, V. et al. Circulation 2001;104:2118-2150
Kastor, J.A. Arrhythmias, Second Edition W.B. Saunders Co.. 2000: pp79-81
Anti-arrhythmics
Fuster et al. JACC.2006;48(4):e149-246
Dronedarone
-Contraindicated in Class IV CHF
Percentage of Patients Remaining Free of Recurrence of Atrial
Fibrillation
Roy, D. et al. N Engl J Med 2000;342:913-920
18% of the patients receiving amiodarone and 11% of patients
receiving sotalol or propafenone had to discontinue therapy because
of adverse effects
RACE II
RACE II
Surgical Modification
• Cox-Maze
• Several
Modifications
• Variable results
– ? Data
• Still considered
the ‘Gold
Standard’
Dr. Cox?
Evolution of percutaneous AF
ablation
• 1994 John Swartz first reports endocardial
maze procedure
• 1998 Haissaguerre isolates pulmonary
vein “culprit”
• 1999-2003 more PVs, more foci
• 2003 Pappone anatomic approach
• 2004 Morady Need to isolate 4/4 veins
• 2004 Pappone ablate vagal efferent
Marine, Prog Card Disease 2005
Pulmonary Vein Isolation
Alternative approach
Success rates for ablation outside
the PV
“success rates 2-3 times that of antiarrhythmic medications” Verma Circ 2005
Complication in Modern Series
-45 K procedures, 32.5 K patients, 162 centers
-Between 1995 and 2006
-0.98 in 1000 mortality
JACC 2009;53:1798-803
Cost in Medicare Dollars
-50% unsuccessful
Theory: Prevention
Paroxysmal AF
years
Altered
electrophysiology
Hypertension
Sleep apnea
RAAS activation
Fibrosis
Diastolic Dysfunction
Altered substrate
Persistent AF
Permanent AF
Non-Antiarrhythmic Agents for Afib
prevention
Summary
• Highly prevalent condition with significant
associated morbidity and mortality
– Driven mostly by thromboembolic events
• Decision to pursue rhythm control based
on patient symptoms
• Rhythm control
– Anti-arrhythmics still 1st line
– Ablative or surgical therapy- case by case