Atrial Fibrillation Ablation

Cardiology Symposium

December 6, 2004

Paul R. Steiner, M.D.Cardiac Electrophysiology

Case Background:Case Background:

46 yr old athletic woman (cyclist, runner)

3 yr h/o increasingly frequent rapid palpitations paroxysmal AF Often immediately following exercise More recently may occur randomly

No other medical conditions

Initial Evaluation:Initial Evaluation:

ECG : Sinus bradycardia at rest 54 bpm, normal morphology

Labs : T4, TSH, lytes, etc. are WNL Echo : Structurally normal heart Holter : Frequent APCs, occas PVCs; salvos

of AT and AF, some that are associated w/ symptoms on the patient log.

Heart rate range (in sinus): 46 – 138 bpm

Treatment History:Treatment History:

Rate control strategy: Digoxin β – blockers CCBs

Rhythm control strategy: Propafenone (Rhythmol) Flecainide

What next?What next?

Question:Question:

What would you do next to effectively treat her life-style altering paroxysmal AF?

[ A ] Trial of a class IA drug (ex. quinidine).

[ B ] Amiodarone treatment (with regular careful monitoring).

[ C ] Referral for AV junction ablation and high-quality pacemaker

[ D ] Refer for atrial defibrillator implant

[ E ] Refer for catheter ablation of AF

Atrial Fibrillation AblationAtrial Fibrillation Ablation(What we did…)(What we did…)

FOR WHOM?FOR WHOM? ((Paroxysmal Paroxysmal or or PersistentPersistent))

1. AF w/ “significant symptoms” associated

2. Refractory to AADs

3. Absence of severe structural heart dz.

[ E ]

Left AtriumLeft AtriumPosterior Basal ViewPosterior Basal View

R. superior pulmonary vein

R. inferior pulmonary vein

Coronary sinus

L. inferior pulmonary vein

L. atrium

L. superior pulmonary vein

L. auricle

L. pulmonary artery

R. pulmonary artery

Netter F. Atlas of Human Anatomy. 1989;Plate 202.

Nathan, Circ Res, 1969?

Left Atrium, Posterior WallLeft Atrium, Posterior WallVariable Anatomy (Common)

RIPV

RSPV

LIPV

LSPV

IVC

SVC

LAARAA

Left Atrium, Posterior WallLeft Atrium, Posterior Wall

Atrial FibrillationInitiation Mechanism – PV Triggers

Nathan, Circ Res, 1969?

Left Atrium, Posterior WallLeft Atrium, Posterior WallPulmonary Vein Isolation

MediastinumMediastinumAxial Superior ViewAxial Superior View

Netter F. Atlas of Human Anatomy. 1989;Plate 230.

Esophagus

Right Pulmonary

Veins

Left Pulmonary Veins

Aorta

Azygous Vein

Left Atrium

Right Atrium

T8 Axial ViewT8 Axial View

Courtesy of M. Ramsey, PhD, CEO CardioCommand

Right PVs Left PVs

Esophagus Aorta

LeftVentricle

Atrial Fibrillation AblationAtrial Fibrillation AblationTechniqueTechnique

Combined ModalityCombined Modality ImagingImaging

1. Fluoroscopy (biplane, for rapid 3-D estimates)

2. High resolution gated CT or MRI

3. 3-D electroanatomic mapping

4. Intracardiac echo

In the future:

Multi-modality image co-registration combining real-time anatomy and function…

Cu

rre

nt

Left Atrium (LA) andLeft Atrium (LA) andPulmonary Vein AnatomyPulmonary Vein Anatomy

3-D CT Reconstruction

(Extreme PA Cranial View)

LA Roof

Esophagus

Left PVs

Right PVs

LA Appendage

Side-by-Side GeometrySide-by-Side GeometryElectroanatomic Map & 3-D CT: Cranial ViewElectroanatomic Map & 3-D CT: Cranial View

ESI Nav-X 3-D Geometry 3-D CT via CardEP

(Cranial View)

LA Roof

Esophagus

Left PVsRight PVs

LAA

ESI Nav-X 3-D Geometry 3-D CT via CardEP

Side-by-Side GeometrySide-by-Side Geometry RF catheter pointing RF catheter pointing awayaway from esophagus from esophagus

Pulmonary Vein IsolationPulmonary Vein IsolationSegmental ApproachSegmental Approach

Haïssaguerre, M. et al., Circulation. 2000;102:2463–2465.

Going…Going… Going…Going… Gone !Gone !

LA Mapping and Catheter AblationLA Mapping and Catheter AblationVisualizationVisualization:: Intracardiac UltrasoundIntracardiac Ultrasound

Facilitate transeptal access to LA Visual guidance of catheters at PV ostium RF energy delivery titration via “bubble” monitoring Doppler PV flow (assess for size and stenosis)

Direct visualization of: PV ostial size Anatomic abnormalities Pericardial effusion Thrombus

Left Atrial Mapping and Catheter AblationLeft Atrial Mapping and Catheter AblationVisualizationVisualization:: Intracardiac UltrasoundIntracardiac Ultrasound

Transeptal Access to LATranseptal Access to LA

Tenting of theintra-atrialseptum duringtranseptalcatheterization

AcuNav 10 Fr Phased Array Diagnostic Ultrasound Catheter (by Acuson)

Left Atrial Mapping and Catheter AblationLeft Atrial Mapping and Catheter AblationVisualization Visualization : : Intracardiac UltrasoundIntracardiac Ultrasound

Optimizing Catheter Placement at PV OsOptimizing Catheter Placement at PV Os

CautionCaution

STOP !STOP !

Marrouche N and Natale A. Electromedica 70 (2002) no. 1

PV Isolation by RF LesionPV Isolation by RF Lesion

Before …

Electronically Isolated PVElectronically Isolated PV

After …

FOR WHOM?FOR WHOM? ((Paroxysmal Paroxysmal or or PersistentPersistent))1. AF w/ “significant symptoms” associated

2. Refractory to AADs

3. Absence of severe structural heart dz

HOW?HOW?1.1. Electrical isolation of pulmonary veinsElectrical isolation of pulmonary veins

2.2. Atrial tissue substrate modificationAtrial tissue substrate modification

3.3. Accomplished via catheter ablation combined w/ Accomplished via catheter ablation combined w/ multiple imaging modalitiesmultiple imaging modalities

SUMMARYSUMMARYAtrial Fibrillation AblationAtrial Fibrillation Ablation