Download Atrial Fibrillation Management: 2005

Catheter Ablation of Atrial
Fibrillation: Who? How?
How Good?
John D. Day, M.D.
Director, Utah Cardiovascular Research Institute
Utah Heart Clinic Arrhythmia Service
LDS Hospital
*Disclosure: No conflicts of interest, no relationships to disclose*
Atrial Fibrillation: Magnitude of
the Problem
• 15-30% of all strokes from atrial fibrillation
• Heart failure risk increased with atrial fibrillation
• 2.5x mortality increase with atrial fibrillation
(Framingham data)
• 1 in 4 people age 40 will develop Afib
• No effective or safe medications for atrial fibrillation
• Anti-arrhythmics may increase mortality or expose
patient to significant toxicities
• Increasing risk factors: age, hypertension, heart failure
JACC 2003;41:2185-2196, Circulation 2004;110:1042-1046
Ablation of Atrial Fibrillation
1. Mechanisms of Atrial Fibrillation
2. Historical Approach to Catheter
Ablation of Atrial Fibrillation
3. Our Approach to Catheter Ablation of
Atrial Fibrillation
4. Future Directions
Mechanism: Wavelet Hypothesis
• Multiple wavelets – Moe and
Abildskov 1959
• “Multiple independent reentrant
wavelets are necessary to maintain
fibrillation. These wavelets are
always changing in position, shape,
size and number with each
successive excitation”
• Confirmed by animal/human
mapping techniques
Moe, Am Heart J; 1959
Results
• 94% of atrial
fibrillation
triggers
(premature atrial
beats) arise
from pulmonary
veins
• Pulmonary Veins
as source of
atrial fibrillation
(Winterberg,
1906)
RA LA
New England Journal of Medicine 1998;339;659-666
Why the Pulmonary Veins? Myocardial
Tissue Lines the Pulmonary Veins
Left Atrium
Pulmonary vein lumen
Pulmonary Vein Isolation 1998-Present
• Electrical isolation of pulmonary vein triggers
(premature atrial beats)
• Success: 50-90%
• Increased success without pulmonary vein
stenosis by isolating outside of vein (antrum)
• Evolution of Technique
–
–
–
–
Focal
Circumferential
Segmental
Antrum isolation
Mapping of Atrial Fibrillation Trigger
to Left Upper Pulmonary Vein
Electrical Isolation of Pulmonary Vein
Sinus rhythm by EKG
A A A A A A A A A A A A AA A
Atrial fibrillation in pulmonary vein by Lasso catheter
AV
AV
Sinus rhythm by left atrial
recordings from coronary sinus
Limitations of Pulmonary Vein
Isolation: Pulmonary Vein Stenosis
Before Ablation
After Ablation
>50% reduction in
ostium of left superior
pulmonary vein
J Cardiovasc Electrophysiol 2003;14:150-153
2003: Wavelets and Pulmonary
Vein Triggers Both Important
Moe, Am Heart J; 1959
Convergence of Techniques:
Pulmonary Vein Isolation and Left Atrial
Substrate Modification: 2003-Present
• Isolation of pulmonary veins (triggers) and modification
of substrate both important (wavelet mechanism)
• New technique: left atrial ablation, wide area
circumferential ablation, circumferential left atrial
pulmonary vein ablation (Pappone, Morady, and others)
• Increased success by isolating/encircling outside of the
pulmonary veins (pulmonary vein stenosis eliminated)
• Ongoing issue: Electrical isolation of pulmonary veins
by Lasso catheter or anatomic lesion set with
pulmonary vein conduction delay (no Lassovoltage
reduction)
Ablation lesion Set
Proposed by Morady in
2003 (based on
Pappone approach):
• Anatomic ablation
lesion set
• Success rate similar
if pulmonary veins
isolated by Lasso
catheter versus
voltage reduction with
an anatomic approach
(Lasso not used)
Circulation 2003;108:2355-2360,
Journal of the American College of Cardiology 2005;46:1060-1066
2004: Targeting Autonomic
Inputs/Fractionated Electrograms
Location of the Left Atrial
Ganglionic Plexi
Heart Rhythm 2005;2:S11
Autonomic/Fractionated Electrogram Approach
Lesion sets similar to the wide area
pulmonary vein circumerferential
ablation approach!!!
Journal of the American College of Cardiology 2004;43:2044-2053
New Paradigm for Atrial Fibrillation
Pulmonary
Vein and Autonomic
Triggers
In progression
to persistent
and permanent
atrial fibrillation
triggers
become less
important
Electrical
Remodeling
Drugs
Multiple
Wavelets
Substrate
• Atrial Size
• Fibrosis
• Stretch
Mortality and Morbidity with
Atrial Fibrillation Ablation
• 1,171 consecutive patients referred for ablation in
Milan, Italy (January 1998  March 2001)
• 589 ablated versus 582 drug treated (1/3
amiodarone, 1/3 class Ic, 1/3 sotalol/class Ia)
• End-points: mortality, morbidity (heart
failure/stroke), & quality of life (900 day follow-up)
Journal of the American College of Cardiology 2003;42:185-197
Pappone Approach
Each pulmonary
vein encircled
(voltage reduction)
2 Posterior wall
ablation lines
Mitral valve flutter
ablation line
Right atrial cavotricuspid isthmus
flutter line
Ablation versus Drug Success
78%
37%
Journal of the American College of Cardiology 2003;42:185-197
Mortality After AF Ablation
54% Mortality Reduction
Mortality After AF Ablation =
with Ablation versus Drug
Expected for Italian Population
Atrial Fibrillation mortality on Drug
Less than Expected Italian Mortality
Journal of the American College of Cardiology 2003;42:185-197
Morbidity After AF Ablation
55% reduction in heart failure or
stroke at 3 years in ablated patients
versus drug treated patients
p<0.001
hello
Journal of the American College of Cardiology 2003;42:185-197
Our Current Approach: 3D CT and
CARTO Electroanatomic Imaging
Our Results: LDS Hospital
• 49 consecutive patients age 59±11 (Jan 1, 2004 –
October 1, 2004—now 300+)
• 7±3 months follow-up
• Drug refractory symptomatic atrial fibrillation (failed
2.3 ± 1.2 anti-arrhythmic drugs)
• 36 paroxysmal and 13 persistent atrial fibrillation
• LA size: 48 ± 8 mm, 16 with structural heart disease
• Follow-up: Pacemaker/ICD logs, Holter, event monitor
• Approach: Encircle pulmonary veins (end-point of
voltage reduction), roof and mitral line, target
autonomics and complex fractionated electrograms
12th World Congress of Cardiology, Vancouver 2005
Atrial Fibrillation Ablation Results:
LDS Hospital
Atrial Fibrillation Free
Atrial Fibrillation Free (no drugs)
n=49
100%
80%
60%
92%
72%
40%
20%
0%
Freedom from Atrial Fibrillation (4+ Months Out)
12th World Congress of Cardiology, Vancouver 2005
Complications
• 300+ cases now performed utilizing this
technique (2004-2005)
• No strokes
• 3 pericardial effusions requiring
pericardiocentesis (1%, experience related)
• 1 atrio-esophageal fistula*
• 1 esophageal perforation*
– Successful temporary esophageal stenting
– No long-term problems
*Early in experience before ultrasound monitoring
12th International Congress of Cardiology, Vancouver 2005
New Achilles Heel: Potential
Esophageal Injury
Posterior
LA Wall
Esophagus
Our Approach to Minimize Esophageal Risk:
Intracardiac Echo Monitoring During Radiofrequency
Delivery and Esophageal Temperature Probes
Future Directions: Ultrasound/Cryo
Isolation of Pulmonary Veins?
Problem: “One size doesn’t fit all”
Robotic Approach to Ablations?
Stereotaxis Magnetic Navigation?
Journal of the American College of Cardiology 2003;42:1952-1958
As most strokes from atrial fibrillation
arise from the left atrial
appendage…Closure after ablation?
• Who?
Final Points
– Ideal patient: Young, paroxysmal atrial fibrillation with
no structural heart disease
– Success rate lower with permanent atrial fibrillation
and structural heart disease
• How?  3 main “techniques”
– All 3 with similar ablation lesion sets
– Pulmonary vein isolation, wide area circumferential
ablation, Autonomic/fractionated electrograms
– Our approach: Integration of all 3 techniques
• How Good?
– 80-90% success rate in experienced hands with any
technique