Barts and The London Heart and Chest Centre | Your journey of care | Interventional treatment

Barts and The London Heart and Chest Centre

Interventional treatment

There are various procedures that can help to prevent heart attacks and more serious heart problems developing. These are called interventional treatments.

The main procedures include:

Angioplasty

This technique is used to treat narrow or blocked arteries. Angioplasties involve cardiologists inserting a thin tube called a catheter into your leg and feeding it through a main artery until it reaches the blockage.

A tiny balloon attached to the end of the catheter is then inflated to clear the blockage and a tiny metal scaffold, called a stent, is inserted into the artery to stop it from narrowing and becoming blocked again.

Rotablation

Rotablation is a type of treatment for patients with coronary artery disease. Some blockages in the arteries are hard, calcified deposits that do not respond to balloon angioplasty or stent implantation. With rotablation, a small device is used inside the arteries to drill through the calcified blockage. It breaks the calcium into microscopic pieces and disintegrates the blockage.

The rotablator is designed to target hard calcium and not the soft lining of the blood vessels. This technique takes anywhere from 30 minutes to four hours depending on the number of blockages, location of blockages, and the amount of calcium.

Coronary artery bypass graft (CABG)

This procedure improves blood flow to the heart, therefore reducing the risk of heart attack. A blood vessel is taken from the chest, leg or arm to bypass a narrowed or blocked artery. For more information visit our dedicated heart surgery website.

Aortic valve replacement (AVR)

The main purpose of a valve replacement is to relieve the symptoms of a narrowed or leaky heart valve. The heart can usually manage despite a leaky or narrowed valve, but it has to work much harder and can result in heart failure. For more information visit our dedicated heart surgery website.

Catheter ablation of atrial fibrillation

Barts and The London Heart and Chest Centre has been a pioneer in the UK for catheter ablation of AF and currently performs between 300 and 400 of these procedures annually. The procedure is carried out in patients who have symptomatic AF (palpitations, breathlessness or fatigue) where conventional treatments such as medication and cardioversion have not been effective.

On the day of or day before the procedure a trans oesophageal echo (where an echo probe is guided down the gullet), is performed to ensure there is no blood clot in the heart.

The procedure itself is carried out using a local anesthetic where patients are awake but sedated in the cardiac catheter laboratory.

Tubes are inserted in the top of the leg to allow the ablation catheter to be passed into the left atrium - the chamber of the heart which usually contains the abnormal heart cells producing AF.

Ablation using either radiofrequency energy (heating) or cryoenergy (freezing) is delivered at critical sites to destroy these cells. The procedure usually lasts 3-4 hours. Patients stay in hospital for a night following the procedure.

The success rate of AF ablation is between 65 and 80% depending on the type of AF.

In many patients a repeat procedure is needed. Serious complications occur in 1 in every 50 procedures. These complications include stroke, perforation of the heart, damage to the veins of the heart, damage to the veins in the leg and extremely rarely, death. These risks will be discussed with you prior to the procedure.

Catheter ablation of other fast heart rhythms (SVT, flutter)

Catheter ablation is a treatment that can cure abnormal heart rhythms by burning away the source of the problem. But the heart rhythm must fulfil two main criteria:

it must be sustained and
it must be tolerated by the patient for long enough to allow enough time for us to find the source.

At Barts and The London Heart and Chest Centre, we have developed catheter ablation techniques that allow the treatment and elimination of almost all regular abnormal rhythms like SVT, atrial flutter and VT. Approximately 300 of these procedures are performed annually.

The procedure is performed in the cardiac catheter laboratory.

Your skin will be cleaned at the top of your legs and tubes will be inserted following a local anaesthetic. You will be covered with sterile towels to avoid infection.

The anaesthetic will sting as it first goes in but after this you should only feel pushing and pulling and no pain.

We are also happy to provide you with sedation medication as and when you need it, although sometimes this reduces our chances of bringing on your abnormal rhythm, thus making treatment impossible.

We will then introduce wires (electrode catheters) to the heart using X-ray to guide us. These wires allow us to both record the electrical activity of the heart and stimulate (pace) the heart using very small electrical currents.

When the wires are in position we then study the hearts' electrical system and attempt to bring on the symptoms of palpitation.

Many patients worry about this part of the procedure because they find their symptoms very distressing, but remember that we are monitoring you carefully throughout and can stop any abnormal rhythm whenever we have to.

When we have identified the problem, we will then perform the ablation. Some patients may experience a feeling of warmth or even pain in the chest during the 60 seconds of energy delivery and if this does happen we can give you pain killers to prevent this. Most people feel nothing.

After the procedure, the catheters and tubes will be removed and you will rest in bed for a short period. You are usually able to go home the same day depending, although this does depend on the complexity of the procedure.

Bruising of the legs at the site where the electrodes were inserted may occur. This will usually settle completely in after two or three weeks.

In the period following the procedure you may feel extra beats - as though your rhythm was about to start.

These “ectopic” beats are felt by almost everyone and they aren't a sign that the procedure has failed. Once the cause of the abnormal rhythm has been removed, these beats will no longer have an effect.

Cardioversion

DC cardioversion is a treatment to correct certain fast heart rhythms such as atrial fibrillation. Under sedation or general anaesthetic, a brief electric shock is passed across the heart, restoring the normal rhythm.

This can be done either by placing paddles across the chest (external cardioversion) or by feeding a small tube up to the heart from the groin (internal cardioversion).

In some cases the heart remains in the normal rhythm following DC cardioversion but in other cases the fast heart rhythm reoccurs and other treatment such as medicines and/or catheter ablation are recommended.

Pacemakers

A pacemaker is an implantable device used to monitor the heart rate and to treat slow heart beats.

It consists of a small flat metal box (pulse generator) containing a battery and electronic circuitry.

The box is usually implanted deep under the skin below the collar bone and is connected to one, two or three thin leads that pass inside the vein of the chest to the heart.

If the heart rate drops below a certain level, the pacemaker sends out a tiny electrical impulse to stimulate the heart until it's natural rate increases again.

Most pacemakers are inserted under local anaesthetic as a day case procedure.

All patients who have a pacemaker need to attend a pacemaker clinic every few months in order to have their heart rhythm and the pacemaker checked.

Implantable cardioverter defibrillators (ICD)

Barts and The London Heart and Chest Centre, at St Bartholomew's, is one of the largest ICD implantation centres in the UK performing over 300 implants annually. Our procedural complication rates are amongst the lowest in the UK.

ICDs are specialised devices that perform all the functions of a standard pacemaker, but they also have the ability to treat fast, life threatening heart rhythms that may result in collapse or cardiac arrest.

The implantation procedure is very similar to that for a pacemaker and is performed as a day case procedure using local anaesthesia and sedation at St Bartholomew’s Hospital. Most of our patients are followed up in our daily ICD clinic which is one of the busiest in the UK.

The majority of the devices are implanted in patients who have had previous heart attacks and who have experienced or are deemed to be at high risk for life threatening arrhythmias. Increasingly, we are also implanting ICDs in patients with cardiomyopathies such as hypertrophic cardiomyopathy and patients with grown-up congenital heart disease such as repaired tetralogy of fallot.

In addition to providing an excellent clinical service, we are also actively involved in training doctors who wish to specialise in ICD implantation and there is an active research programme with a dedicated Device Fellow.

Cardiac resynchronisation therapy (CRT)

We are one of the largest centres performing CRT in the UK with over 100 implants annually. Our procedural complication rates are amongst the lowest in the UK.

CRT involves implanting either a pacemaker or an ICD in patients with severe heart failure symptoms such as breathlessness, poor exercise capacity and fluid retention.

The majority of patients have previously had a heart attack resulting in poor heart function and a failure of the pumping chambers (right and left ventricles) to contract together.

This reduces the pumping efficiency of the heart and significantly contributes to heart failure symptoms. We also perform CRT in patients with poor heart function due to cardiomyopathies such as dilated cardiomyopathy.

The implantation procedure is more complex than for a pacemaker or an ICD and is performed using local anaesthesia and sedation with an overnight stay in hospital.

An extra pacing lead, in addition to the standard ones for a pacemaker or an ICD, is implanted to allow pacing of the left ventricle. Pacing of both ventricles allows them to contract together and may improve heart failure symptoms.

This lead is usually inserted into one of the veins inside the heart called the coronary sinus and requires the use of specialised equipment. However, in those patients in whom the coronary sinus is unsuitable for this, the extra pacing lead is inserted surgically and placed on the outside of the heart. This requires general anaesthesia and all such procedures are performed together with our cardiac surgeons.