Expert London Cardiologist for your Heart Health

68 Harley Street

London, W1G 7HE
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Cromwell Hospital, Syon Clinic
Bishops Wood

0203 9838 001

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Dr Nijjer's Clinics

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with a Rapid Response

Dr Sukhjinder Nijjer
Consultant Cardiologist

Expert in Heart Attacks
& Acute Coronary Syndromes

Contact us for more information

Heart Attacks Explained

What are Heart Attacks?

Heart Attacks are a life-threatening condition in which a heart artery (‘coronary artery’) blocks suddenly with a clot. Coronary arteries often develop coronary plaque through a process called atherosclerosis. This involves the deposition of cholesterol and inflammatory cells within the lining of the heart artery (which ordinarily are smooth). These plaques can rupture suddenly – exposing collagen within the vessel. Blood sticks to the collagen suddenly and starts forming clumps. Once this occurs, a clot can form. Because the heart arteries are very small, even a small clot can completely block a vessel. In patients with arteries that are already narrowed, less is needed to block the vessel.

When the heart artery is blocked, that area of the heart is not recieving blood and it quickly stops working. This causes the symptoms of a heart attack which are discussed below. If the artery can be treated quickly and opened, then the heart attack can be stopped.

Even patients with very mild atherosclerosis or coronary plaque can have a heart attack and, we often see, these patients are more unwell than those with established heart disease. This appears to occur because younger patients or those with minimal plaque are not used to the lack of blood supply and so their hearts suffer more.

Those patients with established coronary artery disease may have episodes of ‘stable angina’ – this is a discomfort that comes on during exertion, and then goes away during rest. Those with angina are often well treated on multiple medications and this can dramatically reduce the risk of a heart attack. 

Heart Attack Treatment
Heart Attack Treatment: get the right treatment for your heart attack.

What symptoms occur during a heart attack

Heart Attacks can occur at any time, including the early hours of the morning or during sleep. Heart Attacks also increase particularly at times of stress because this causes sudden changes in blood pressure (‘hypertension’). 

The key symptom is a sensation feeling of a heaviness across the chest – like a band or belt across the chest. This discomfort, (many doctor’s frequently refer to this as a ‘pain’, but most patients says it isn’t really a pain, rather a sensation of heavy weight on their chest) can move into your arm or neck. 

Classically, we think of left arm discomfort being related to the heart, but the discomfort can move into the right arm, both or even into the back. 

Patients will feel uncomfortable, sometimes with sense of dread or fear. They may become sweaty, cold and clammy. Patients having a heart attack often vomit, or may retch. 


These symptoms can be short lived, lasting only for a few minutes. In these situations, the heart artery may have re-opened temporarily but action should still be taken. It is known that severe heart attacks often have ‘warning’ episodes that came earlier in the day or week. 

Symptoms that are ongoing and progressive – getting worse with time, should trigger people to call for an ambulance. In the UK, patients should call 999. In the USA, it is 911. You should tell the telephone operator that you are having severe crushing chest pain and them where you are. If you are alone, you should go to the front of the house and open the front door.


How are Heart Attacks Treated? The first steps

Urgent treatment is essential. All patients with a heart attack need to be assessed urgently in a Hospital. 

When patients are first picked up an ambulance, they will undertake an ECG and give the patient Aspirin 300mg (usually best chewed). Patients are also given a GTN spray or tablets under the tongue. This a nitrate medicine that causes the coronary arteries to dilate and expand in size. 

In some cases, the GTN spray can help stop or slow down the progress of some heart attacks. Patients are then taken to Hospitals. 

In London, patients with certain ECG changes will be taken to ‘Heart Attack Centres’ which operate with a full team on standby 24/7/365. 

Once there, they will be assessed promptly and have an ECG, a bedside echocardiogram and treatment with blood thinning medicines. This can include Aspirin with Clopidogrel, or Ticagrelor or Prasugrel. A high dose is required when it is first started. An injection of a type of heparin is also given – such as fondaparinux. 

Coronary artery disease

How are Heart Attacks Treated?


If there is no ST elevation, called ‘NSTEMI’, then the treatment will be according to the patient’s risk scores and their progress. In my practice, we typically perform coronary angiography within a 24 hour period and sooner if possible. 

In ‘STEMI’ angiography and angioplasty must be performed as fast as possible. Ideally this should be within 2 hours of the chest pain starting, and within 1 hour of attending the hospital if it has capabilities (all ‘Heart Attack Centres’ in London are able to do this). 

The need for urgency is simple: the coronary artery is fully blocked by clot, and the longer it remains blocked, the more heart damage occurs. The amount of damage can be estimated by blood tests called Troponin and by scans such as echocardiography. 

In some cases, particularly in the Left Anterior Descending (LAD) Artery this can leave very severe scarring and weakened heart (Heart Failure). 

If the Right Coronary Artery (RCA) is blocked, then the electrical conducting system of the heart can be disrupted and the patient can develop a condition called Complete Heart Block.  In this situation, prompt treatment of the heart attack will resolve the Complete Heart Block, but if there is no treatment a Pacemaker may needed. Without treatment, the heart can stop.

Heart Attack Treatment: get the right treatment for your heart attack.
Heart Attack Treatment: get the right treatment for your heart attack.
Left anterior descending (LAD) artery with severe obstruction
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DC Cardioversion

What happens if heart attacks are not treated rapidly?

If heart attacks are not treated within the right time frame, then considerable heart damage can occur. If more than 12-hours have elapsed since severe chest pain started, there can be limited value from Angioplasty as the heart damage is usually complete. 

During the Covid-19 pandemic, I have seen many patients presenting very late after their heart attack started. They have a lot of clot within their heart arteries and this has been difficult to treat. 

The potential complications are:

1.Heart Failure

2.Arrhythmia – including atrial fibrillation

3.Valve disruption

4.Holes within the heart

5.Clot within the heart

6. Cardiac Arrest – the heart stops

Complications of untreated Heart Attacks

Heart Failure

I have seen patients be left with severe Heart Failure – where the pumping function of the heart is severely reduced. Acute heart failure can mean the lungs fill rapidly with water causing severe acute breathlessness. Even when stabilised, these patients will be breathless and fatigued when they do their activities. Their ankles may swell and they may not be able to lie flat. A lot of medications are required and in many cases, this can stabilise a patient. However, it is well established that heart failure can have a worse prognosis than many cancers.


Those patients with a lot of scar can suffer from arrhythmias – this is a problem with the conducting issue of the heart. Atrial fibrillation is a common arrhythmia and can be triggered after a heart attack but it is rarely life threatening. In some patients, ventricular tachycardia or ventricular fibrillation can occur. In both situations, these are life-threatening arrhythmias and require near instantaneous treatment. Without an electrical shock to the heart, the patient will die. 

Leaking mitral and tricuspid valves

Patients with untreated heart attacks can also have scarring of parts of the heart that hold together the heart valves. This means the valves can be acutely disrupted, causing severe leaking. Acute mitral regurgitation can cause the patient to become destabilised with sudden water on the lungs. Performing an operation to fix this valve can be difficult and risky in the context of an acute heart attack. 

Left Ventricular Thrombus

In patients with significant heart attacks, parts of the heart stop working such that the blood does not move properly. This allows clots to form within the heart. This is dangerous as these clots can fire off smaller clots which tend to travel to the brain. This can cause devastating stroke – a condition where part of the brain stops working. This can cause severe disability and life-long health related issues. Very careful blood thinning is required to prevent this from occurring. 


Heart failure is dangerous
Stroke can be a complication of a heart attack
High blood pressure is a cause of heart disease
High blood pressure is a cause of heart disease

Medicines required after a Heart Attack

Following a heart attack, a number of different medications are needed.


1. Aspirin: this is a blood thinning medicine and is given to nearly all patients. This is given to reduce the risk of further heart attacks. It is taken at the low dose of 75mg once a day and it is best taken after food to reduce the risk of stomach upset. It can cause stomach ulcers in some vulnerable patients. The Aspirin should not be stopped unless instructed by a Cardiologist. If you need another operation or procedure, other Doctors may ask you to discontinue it. You must inform them that you have had a heart attack and that you have stents placed. They will usually liaise with your Cardiologist, such as Dr Nijjer, and have a discussion about the pros and cons of performing a procedure on Aspirin.


2. Clopidogrel / Ticagrelor / Prasugrel:  These three medicines are also blood thinning medicines and act like ‘Super-Aspirins’. When taken on top of Aspirin, they significantly reduce the risk of further heart attacks.

– Clopidogrel has been used since the late 1990s and is very safe but can cause skin reactions in some patients. It is usually taken as 75mg once a day and can be taken at the same time as the Aspirin. It is essential to take this for 1 year after a heart attack – it reduces further heart attacks and reduces the chance that your heart stents will suddenly block again (Stent Thrombosis – a life threatening condition). 

Ticagrelor has been in use over the last 10 years and is much stronger. than Clopidogrel. Some studies have shown it is better than Clopidogrel in certain patient groups but it does cause more bleeding issues in older patients. It is taken as 90mg Twice a Day – this means you must remember to take the morning and evening pill. It’s main side-effect is a tendency to a sensation of breathlessness. It does not alter your lungs, but creates a mild feeling of needing a big ‘sigh’. This is not dangerous and will not harm you. 

Prasugrel is another alternative that gained prominence in the late 2000s but was then supplanted by Ticagrelor.  This medication is getting prominence again and is increasingly being used in the UK. It is a more powerful version of Clopidogrel and is typically taken as 10mg once a day. In some patients (those over 75 years of age or low body weight <60kg) we use 5mg a day. We avoid Prasugrel in those patients with prior stroke or transient ischaemic attack (TIA). 



Other Medications needed after a Heart Attack

3. Statin Medication: Statins are medications that reduce blood cholesterol levels by altering the activity of a liver enzyme responsible for cholesterol processing. They are derived from a natural product found in Chinese red yeast rice that was found to reduce cholesterol levels. They have been extensively tested over the last 30 years and, in those who have had a heart attack, they have a clear benefit over not taking the medication (compared to placebo). In those patients who have not had a heart attack – the beneficial effect is not as prominent as seen in those who have had a heart attack.  They have an immediate effect and are often started on the day of the heart attack – studies have shown they can pacify the angry plaque that has ruptured and caused the heart attack.  There are many statins, but the one used most commonly after a heart attack is Atorvastatin 40mg or 80mg. Others include Rosuvastatin or Simvastatin. Pravastatin is an older statin that is generally kept in reserve for those patients who cannot take the other, better, versions. In general, these doses are well tolerated, but some patients get aches and pains in their large muscle groups such as their thighs. Some patients may joint pains. It is common to have small changes in their liver enzymes. If there are large changes in liver enzymes or an acute rise in the muscle enzymes, we may need to stop the statin for either a short time or indefinitely.  


4. Beta-blocker Medication: Beta-blockers are medicines that calm down the heart muscle and stop it from racing at a fast rate. In many patients after a heart attack, we start a beta-blocker to reduce the heart strain but we may discontinue it in the future if the heart muscle is healthy. In those patients left with heart scarring or reduced heart function, we keep them on beta-blockers as they are associated with patients living longer. We use beta-blockers such as Bisoprolol or Carvedilol and we increase the dose until we have achieved a heart rate of around 60 beats per minute.  Beta-blockers have only a limited effect on blood pressure.  Most patients tolerate beta-blockers very well, but they may get a feeling of fatigue and tiredness when they first start. Consistent use leads an improvement in this symptom. Some suffer with cold hands or feet. Some men may find it hard to achieve or maintain an erection. If these issues occur, please tell Dr Nijjer. 


6. ACE-Inhibitors: ACE-inhibitors such as Ramipril and Perindopri are often used as blood pressure medication, but have an additional benefit on the heart. They block an abnormal pathway (triggered by the kidneys) which, if not stopped, causes a worsening of heart function. They have become the mainstay of heart failure and all patients with any weakness of the heart muscle will be given one of these drugs. Ramipril can be dosed such that you take it twice a day. They are generally well tolerated, but do cause lower blood pressure, and in around 10%, cause a recurrent dry cough. If this occurs, please let Dr Nijjer know and he may consider switching to another medication such as Candesartan or Irbesartan – medications which have a similar effect as the ACE-inhibitors.


7. There are other medications that may be needed. A number of medications have been shown to improve heart function after heart attack including extra blood thinners such as Rivaroxaban or special medicines ordinarily used in diabetes, called SGLT2-inhibtors (Dapagliflozin, Empagliflozin or Canagliflozin). Dr Nijjer will use the latest research evidence to prescribe these medicines to you.  


High blood pressure is a cause of heart disease

Healthy living after a Heart Attack

After a heart attack, you will have a programme of Cardiac Rehabilitation that will explain to you the lifestyle changes that may be necessary. In many patients, you can get back to normal activity very quickly. Dr Nijjer will taylor your diet, exercise regimen and activities specific to you.


Help Your Heart

If you have any concerns regarding your heart health, then please seek a referral to Dr Nijjer.  


Call the Team: Monika, Amy, Charlotte, Erin or Grace:

0203 9838 001


Dr Nijjer can be seen at :

68 Harley Street, London, W1G 9QP

He also practices at Cromwell Hospital, Wellington Hospital, BUPA Clinics, BMI Syon Clinic as well as Imperial Private Healthcare.

Contact Us

Please send us your details and we will contact you. Dr Nijjer will strive to help you. 

Dr Sukhjinder Nijjer Consultant Cardiologist

One Heart Clinic
68 Harley Street
London, W1G 7HE

0203 9838 001

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