Cardiac Devices Testing

What is cardiac device testing and why do I need it?

Patients who had a Permanent Pacemaker or Defibrillator implanted will need the device tested on a regular basis to ensure it functions properly and have sufficient battery for the foreseeable future. A device’s malfunction or lack of battery could have serious consequences.

How is the procedure performed?

A device check/interrogation involves you in a sitting position while an experience cardiac technician placing a wand over your chest wall where the device is to communicate through a programmer. It takes only 10 to 15 minutes and a medical practitioner will review the results of the interrogation and let you know how your device has been functioning.

Permanent Pacemaker Implantation

What is a permanent pacemaker and why do I need it?

A Permanent Pacemaker could be implanted to treat abnormally slow heart rate when the natural electrical system of the heart fails. It improves symptoms (more energy, less faints, less breathlessness etc) for some patients. It could also be a lifesaving procedure for some patients.

A pacemaker has two parts. The pacemaker leads are thin insulated wires that carry electrical signals back and forth between the generator and the heart. It can sense when the heart is beating too slowly and needs treatment. The pacemaker generator is a small device that has computerised parts that run on a battery. It sends a very small amount of electrical energy to the heart through the leads. Patients usually can not feel the treatment at all.

How is the procedure performed?

You will be admitted to a hospital on the day of the procedure. The procedure is carried out in a sterile room and you lie on an exam table. You will be given sedation during the procedure. The pacing lead will be inserted through a vein in your upper arm (usually left) and gently steers into the

right side of the heart under the guidance of real-time X-rays. You may have one or two leads inserted depends on your condition. The leads then get connected to the small generator which sits under the skin at your upper chest. A clean dressing will cover over the incision site with a tighter dressing on top. The wound generally heals in a week time and your doctor will examine the area again.

You will stay overnight and have the device tested the next day. If no issue occurs, most patients will go home after that. You will receive more information about the pacemaker from the Device Company and hospital before and during your admission.

Implantable Cardioverter Defibrillator Implantation

What is Implantable Cardioverter Defibrillator (ICD) and why do I need it?

Under certain circumstances the beat of the heart can become abnormally fast in a very dangerous way – this usually occurs in people who already have major abnormalitites of the electrical system of the heart. An ICD is an electrical device that can detect and treat abnormally fast heartbeats by delivering a shock to the heart. An ICD is made up of a pulse generator and 1-3 leads that arise from the generator and go into the heart. The leads transmit the electrical inpulses or shock from the pulse generator to the heart muscle.

How is the procedure performed?

You will be admitted to a hospital on the day of the procedure. The procedure is carried out in a sterile room and you lie on an exam table. You will be given sedation during the procedure. The pacing lead will be inserted through a vein in your upper arm (usually left) and gently steers into the right side of the heart under the guidance of real-time X-rays. You may have one or two (or three) leads inserted depends on your condition. The leads then get connected to the small generator which sits under the skin at your upper chest. A clean dressing will cover over the incision site with a tighter dressing on top. The wound generally heals in a week time and your doctor will examine the area again.

You will stay overnight and have the device tested the next day. If no issue occurs, most patients will go home after that. You will receive more information about the pacemaker from the Device Company and hospital before and during your admission.

Atrial Flutter & Atrial Fibrillation Ablation

What is Atrial flutter and fibrillation ablation and why do I need it?

Atrial Fibrillation: Atrial Fibrillation is due to the development of electrical short circuits inside the top chambers of the heart – usually beginning in the left atrium. This can result in very rapid and erratic conducting of the heart’s chambers producing shortness of breath, tiredness, dizziness and palpitations. It also results in ineffective pumping of the upper chambers which lead s to slow blood flow in the upper chambers which can lead to blood clots and possibly stroke.

Atrial fibrillation ablation is recommended to those patients who are having frequent, symptomatic episodes of atrial fibrillation to a point that it is having an impact on their quality of life.

Atrial Flutter: Atrial Flutter is due to a short circuit in one of the upper chambers of your heart. This can result in rapid and sometimes erratic pumping of the chambers which can lead to shortness of breath, palpitations, tiredness and in some, dizziness. It also results in ineffective pumping of the

upper chambers which leads to slow blood flow in the upper chambers which can lead to blood clots and possibly stroke.

An ablation is a procedure aimed at maintaining normal (sinus) rhythm. This procedure does have several associated risks that should be discussed with your treating Electrophysiologist. Radiofrequency Ablation is the most common means of ablation. Pulmonary Vein Isolation is performed around the entire circumference of the Pulmonary Vein to disconnect all the electrical connections between the vein and the heart. This is performed in all patients undergoing atraila fibrillation ablation. Linear Ablation is performed joining anatomical structures (such as two pulmonary veins) – the result is an obstruction to electrical conduction and encourages atrial fibrillation/flutter to terminate. This is performed if you have longer episodes of atrial fibrillation or in those with other heart abnormalities.

How is the procedure performed

Atrial Fibrillation: You will be admitted to hospital on the day of your scheduled procedure. The procedure will be carried out in a sterile Cath Lab and you will lie on an exam table. The nursing staff will then set up monitoring including ECG, X-Ray, blood pressure, oxygen saturation. You will be given a general anaesthetic for this procedure. Once under the effects of the anaesthetic, you will undergo a trans-oesophogeal echocardiogram to assess the heart before the procedure. The catheters are guided to your heart through the femoral vein in the groin using x-ray guidance. Once the catheters are in place, the ablation process wil begin. The duration of the procedure is quite variable and in general will take between 1 and 3 hours.

You will stay in hospital overnight and a transthoracic echocardiogram will be performed the next day.

Atrial Flutter: You will be admitted to hospital on the day of your scheduled procedure. The procedure will be carried out in a sterile Cath Lab and you will lie on an exam table. The nursing staff will then set up monitoring including ECG, X-Ray, blood pressure, oxygen saturation. You will be given a local anaesthetic at the site of catheter insertion and a light sedation for this procedure. Once under the effects of the anaesthetic, the catheters are guided to your heart through the femoral vein in the groin using x-ray guidance. Once the catheters are in place, the ablation process wil begin. The duration of the procedure van be quite variable and in general will take between 30 minutes and 2 hours.

Electrophysiological (EP) Study & Supraventricular Tachycardia Ablation

What is EP study/SVT ablation and why do I need it?

An Electrophysiological Study is a test used to study the electrical function of the heart. It is a common procedure used to stimulate the heart in order to establish where the abnormal conduction is coming from within the heart.

There are 3 main types of Supraventricular Tachycardia:

1. AN Nodal Re-entry Tachycardia (AVNRT)

This is the most common form of SVT. It is an abnormal short circuit that occurs near the AV node where instead of a single AV node between the top and bottom chambers, there is a second connection that is abnormal.

2. Re-entrant Tachycardia

This is an abnormal circular conduction utilising the AV node and an ‘accessory pathway’ connecting the atria and the ventricles. This connection has been present since birth and is often termed Wolff-Parkinson-White Syndrome.

3. Atrial Tachycardia

This is the least common form of SVT. This occurs because of an extra abnormal origin of the electrical impulse from a small area in the atria other than the SA node.

The success rate of an SVT ablation depends on the type of SVT present but is usually approximately 95%-98% if the tachycardia is inducible on the day of the procedure. An SVT Ablation is a cure for this condition