Radiofrequency Radiofrequency Catheter Ablation Catheter Ablation

(Cardiac Ablation)(Cardiac Ablation)

By: Silvia WongBy: Silvia WongRDSC 326—CVTRDSC 326—CVTMarch 1, 2006March 1, 2006

What is Cardiac What is Cardiac Ablation?Ablation? A fairly non-invasive treatment for cardiac A fairly non-invasive treatment for cardiac

arrhythmias (irregular heartbeat)—mostly arrhythmias (irregular heartbeat)—mostly painless, some discomfortpainless, some discomfort

Uses mild sedation and local anesthesia—so Uses mild sedation and local anesthesia—so patient is awake most of the timepatient is awake most of the time

Only takes about 2-4 hours to complete, Only takes about 2-4 hours to complete, sometimes up to 8 hourssometimes up to 8 hours

Specifically for treatment of different types of Specifically for treatment of different types of TACHYCARDIAS (rapid heartbeat)TACHYCARDIAS (rapid heartbeat)

Other names for cardiac ablation include:Other names for cardiac ablation include: Cardiac catheter ablationCardiac catheter ablation Radiofrequency ablationRadiofrequency ablation Catheter ablationCatheter ablation Or just simply—ablation Or just simply—ablation

Normal Electrical Activity—Normal Electrical Activity—a beata beat Electrical impulse begins in Electrical impulse begins in

the sino-atrial (SA) node the sino-atrial (SA) node located in the upper right located in the upper right chamber (right atrium) of the chamber (right atrium) of the heart. The impulse spreads heart. The impulse spreads across both atria causing them across both atria causing them to contract simultaneously and to contract simultaneously and squeeze blood into the lower squeeze blood into the lower pumping chambers pumping chambers (ventricles). (ventricles).

While the atria are While the atria are contracting, the electrical contracting, the electrical impulse continues through the impulse continues through the atrio-ventricular (AV) node. atrio-ventricular (AV) node. The AV node is the "gate-The AV node is the "gate-keeper" to the lower chambers keeper" to the lower chambers and is normally the only and is normally the only electrical connection between electrical connection between the upper and lower chambers.the upper and lower chambers.

After a split second pause, the After a split second pause, the impulse then continues down impulse then continues down through both of the ventricles through both of the ventricles causing them to contract and causing them to contract and squeeze blood out to the body squeeze blood out to the body and lungs. and lungs.

Types of Treated Types of Treated TachycardiasTachycardias

AV Nodal Reentrant Tachycardia AV Nodal Reentrant Tachycardia (AVNRT)(AVNRT)

Accessory PathwayAccessory Pathway

Atrial Fibrillation and Atrial FlutterAtrial Fibrillation and Atrial Flutter

Ventricular TachycardiaVentricular Tachycardia

AV Nodal Reentrant AV Nodal Reentrant Tachycardia (AVNRT)Tachycardia (AVNRT)

An extra An extra pathway that pathway that lies in or near lies in or near the AV node and the AV node and causes the causes the impulses to impulses to move in a circle move in a circle and re-entering and re-entering areas it has areas it has already passed already passed throughthrough

Accessory PathwayAccessory Pathway

Extra pathways Extra pathways that exist from that exist from birth that birth that connect to the connect to the atrium and atrium and ventricles and ventricles and causes signals causes signals to travel back to to travel back to the atrium, the atrium, making it beat making it beat fasterfaster

Atrial Fibrillation and Atrial Fibrillation and Atrial FlutterAtrial Flutter

Extra signals originating in Extra signals originating in different parts of the atrium different parts of the atrium causing the atria to beat causing the atria to beat rapidly (A. flutter) or quiver rapidly (A. flutter) or quiver (A. fib)(A. fib)

Ventricular TachycardiaVentricular Tachycardia A rapid, potentially A rapid, potentially

life-threatening life-threatening rhythm originating rhythm originating from impulses in the from impulses in the lower chambers of lower chambers of the heart. The rapid the heart. The rapid rate prevents the rate prevents the heart from filling heart from filling adequately with adequately with blood so that less blood so that less blood is able to blood is able to circulate through the circulate through the bodybody

Who’s involved? Who’s involved?

CardiologistCardiologist Electrophysiology (EP) doctorElectrophysiology (EP) doctor Interventional RadiographerInterventional Radiographer NursesNurses

Equipments UsedEquipments Used

For guidance:For guidance: Fluoroscopy (most Fluoroscopy (most

common)common) UltrasoundUltrasound

RF Catheter RF Catheter Ablation System Ablation System (Chilli system)(Chilli system) Price: $72,827Price: $72,827

Most Common Ablation Most Common Ablation CatheterCatheter

RF CONTACTR RF CONTACTR Dual-curve Dual-curve Ablation Ablation CatheterCatheter 8F and 7F tip offers 8F and 7F tip offers

unique tip unique tip movement allowing movement allowing for precise mapping for precise mapping and ablation in and and ablation in and around anatomical around anatomical structuresstructures

Other Ablation CathetersOther Ablation Catheters

Livewire TC Livewire TC Bi- Bi-directional directional Ablation Ablation CatheterCatheter

Livewire Spiral Livewire Spiral HP Steerable HP Steerable ElectrophysioloElectrophysiology Cathetergy Catheter

Pre-Treatment CarePre-Treatment Care Stop taking blood thinning medication Stop taking blood thinning medication

three days prior to the procedurethree days prior to the procedure Other medications that controls heart rate Other medications that controls heart rate

also need to be stopped, as well as aspirin also need to be stopped, as well as aspirin productsproducts

Diabetics may need to adjust their Diabetics may need to adjust their diabetes medications or insulindiabetes medications or insulin

NPO past midnight prior to the procedure, NPO past midnight prior to the procedure, including water, gum, mints, etc.including water, gum, mints, etc.

If medications are to be taken, then small If medications are to be taken, then small sips of water is allowedsips of water is allowed

Even while brushing teeth, patients are Even while brushing teeth, patients are not allowed to swallow any waternot allowed to swallow any water

How does it work?How does it work? EP doctor inserts a catheter into the EP doctor inserts a catheter into the

femoral artery and feeds it to the heartfemoral artery and feeds it to the heart Tachycardia inductionTachycardia induction Ablation catheter is maneuvered so itsAblation catheter is maneuvered so its

electrode tip is in contact with the abnormal tissueelectrode tip is in contact with the abnormal tissue Location of the ablation target is determined by a Location of the ablation target is determined by a

process called “electrical mapping,” in which the process called “electrical mapping,” in which the catheter is moved from spot to spot to find the catheter is moved from spot to spot to find the appropriate areaappropriate area

Energy known as Radiofrequency (RF) energy is Energy known as Radiofrequency (RF) energy is turned onturned on

This energy “disconnects” the pathway of the This energy “disconnects” the pathway of the abnormal rhythm by destroying small amounts of abnormal rhythm by destroying small amounts of tissue, ending the disturbance of the electrical tissue, ending the disturbance of the electrical flow through the heartflow through the heart

If the catheter location is correct, the tachycardia If the catheter location is correct, the tachycardia is eliminatedis eliminated

Testing is performed to see if tachycardia can be Testing is performed to see if tachycardia can be initiated again, if so—procedure is repeated, if not initiated again, if so—procedure is repeated, if not then the catheter is withdrawn out of the bodythen the catheter is withdrawn out of the body

Other forms of energy used: intense cold—Other forms of energy used: intense cold—cryoablation, freezing the tissuecryoablation, freezing the tissue

Real Procedure ImagesReal Procedure Images

Specially-designed, Specially-designed, multiple-electrode multiple-electrode loop ablation loop ablation catheter deployed in catheter deployed in the left atrium (Left the left atrium (Left anterior oblique anterior oblique view)view)

Catheter position Catheter position during a successful during a successful ablation of a slow ablation of a slow pathway of AVNRTpathway of AVNRT

Success RatesSuccess Rates

It exceeds over 90 percent when It exceeds over 90 percent when used to treat:used to treat: Supraventricular tachycardia—95%Supraventricular tachycardia—95% Atrial flutterAtrial flutter Rare types of ventricular Rare types of ventricular

tachycardiatachycardia Atrial fibrillationAtrial fibrillation Ventricular tachycardia after a Ventricular tachycardia after a

heart attack (lower only 40-50%)heart attack (lower only 40-50%)

RisksRisks Perforation of the heart with leakage of blood Perforation of the heart with leakage of blood

into the sac surrounding the heartinto the sac surrounding the heart Perforation of a blood vessel with leakage Perforation of a blood vessel with leakage

outside of itoutside of it Inadvertent interruption of normal conduction Inadvertent interruption of normal conduction

(which requires a pacemaker)(which requires a pacemaker) StrokeStroke Heart attackHeart attack DeathDeath All very rare: All very rare:

A pacemaker is needed in less than 1 in 200 casesA pacemaker is needed in less than 1 in 200 cases Serious complications occur in less than 1 in 500 Serious complications occur in less than 1 in 500

casescases

Post-Treatment CarePost-Treatment Care

Patients should monitor the procedure site Patients should monitor the procedure site for any redness, swelling, or drainagefor any redness, swelling, or drainage

Incision site should be kept clean and dryIncision site should be kept clean and dry During recovery process, patient is placed During recovery process, patient is placed

on a special monitor—Telemetry Monitoron a special monitor—Telemetry Monitor Telemetry consists of a small box connected by Telemetry consists of a small box connected by

wires to your chest with sticky electrode patcheswires to your chest with sticky electrode patches The box displays the patient’s heart rate and The box displays the patient’s heart rate and

rhythm on several monitors in the nursing unit rhythm on several monitors in the nursing unit for the nurses to observe the patient’s condition for the nurses to observe the patient’s condition closelyclosely

Recovery TimeRecovery Time After procedure, patients need to stay in bed After procedure, patients need to stay in bed

for about 1 to 6 hours to prevent bleedingfor about 1 to 6 hours to prevent bleeding No stitches involvedNo stitches involved Most patients are discharged the same day, Most patients are discharged the same day,

some may have to stay overnight at the some may have to stay overnight at the hospitalhospital

During the first 48 hours, fatigue or chest During the first 48 hours, fatigue or chest discomfort may be experienceddiscomfort may be experienced Some may experience skipped heartbeats or short Some may experience skipped heartbeats or short

episodes of atrial fibrillation after the procedureepisodes of atrial fibrillation after the procedure After the heart has healed, these abnormal After the heart has healed, these abnormal

heartbeats should subsideheartbeats should subside Many resume normal activities within a few Many resume normal activities within a few

daysdays