Heart Attack Overview


Heart attack (myocardial infarction) occurs when the blood supply to the heart is interrupted, eventually leading to damage to the heart muscles.1 The damage can be irreversible if prompt treatment is not provided. If a large part of the heart muscle is damaged, cardiac arrest occurs, resulting in death. A heart attack is a medical emergency and show be treated immediately.1

What is a heart attack?

Heart attacks occur when the blood supply to the heart is suddenly blocked, usually due to a blood clot.2 Lack of oxygen-rich blood supply to the heart can lead to severe damage to the heart muscle, which could be life-threatening. Cardiovascular diseases are one of the major causes of death worldwide, representing about 32% of all global deaths in 2019, with 85% of these due to a stroke or heart attack.3 Most cardiovascular diseases can be prevented by addressing modifiable risk factors, including unhealthy diet, physical inactivity, obesity and excess alcohol and tobacco use.3 It is essential to detect CVDs early to ensure prompt and effective management with treatment and counselling. 


Symptoms of a heart attack varies between individuals, ranging from mild to severe, and some individuals may not exhibit any symptoms at all. The most common symptoms in men and women are chest pain (feeling pressure, heaviness and tightness or squeezing across the heart), while women are more likely to experience other symptoms like shortness of breath, feeling unwell and back or jaw pain. Other common symptoms include:1

  • Pain radiating to the the chest, arms, jaw, neck and back.
  • Feeling lightheaded or experiencing constant fatigue (even after performing light physical activity)
  • Heartburn or indigestion
  • Nausea or vomiting
  • Shortness of breath, coughing or wheezing

Seek medical care immediately if you experience any or a combination of these symptoms to ensure prompt care and prevent permanent damage.1


Heart attacks occur when the coronary arteries, which supplies blood to the heart muscle, becomes narrow from the buildup of fat, cholesterol and other substances. These form ‘plaque’ by a slow process (plaque build up) called atherosclerosis.2. When the plaque ruptures, a clot begins to form at the rupture site. This obstructs the flow of blood through the artery to the heart muscles. When the heart muscle has insufficient oxygen and nutrients, damage or death of part of the heart muscle can occur, called ischemia. The lack of correct treatment can cause irreversible heart muscle damage. There are high chances of cardiac arrest (heart attacks)and even death If a large part of the heart muscle is damaged.1,2

Less common causes include:

  • Drug misuse (stimulants such as cocaine, amphetamines and methamphetamines) can cause narrowing of the coronary arteries restricting blood supply to the heart.
  • Lack of oxygen-rich blood supply to the heart due to carbon monoxide poisoning (from appliances using coal/wood) or lung disease may also damage the heart muscles triggering a heart attack.1

Risk factors

Heart and circulatory diseases are caused by risk factors many of which can be modified, controlled or treated. Non-modifiable risk factors include:

  • Age - The high prevalence of deaths from coronary heart disease were seen among the elderly (at least 60-65 years).
  • Sex - studies showed that men have a greater risk of heart attacks than women, and often in the early years of their life.
  • Race: Heart disease can exhibit severe symptoms in certain races (African-Americans, Mexican-Americans, Indians, native Hawaiians and Asian-Americans) owing to high prevalence of diabetes and obesity.

Common modifiable risk factors include: 

  • High cholesterol levels : fatty substances found in the blood, which when present in large amount, can increase the risk of a heart attack.
  • Hypertension and/ Diabetes mellitus : cause damages to the blood vessels leading to a heart attack.
  • Obesity and physical inactivity
  • Smoking and excessive alcohol consumption
  • High levels of stress
  • Poor dietary choices (eg., increased consumption of heavily processed foods) and nutritional practises.1;2

You can reduce your risk of a heart attack by making a few changes to your lifestyle!

The following lifestyle factors have the greatest impact on your risk of a heart attack. We will also look at what you can do to reduce your risk from today.


Eating healthy is one of the most effective ways to prevent a heart attack. An unhealthy diet with high fat content and salt intake will harden the arteries, causing more fatty plaques to build up in your arteries. This increases the blood pressure and the risk of  heart attack. It is important to eat a balanced diet with fruits, vegetables, and foods that contain healthy fats like fish, nuts, seeds, beans and limit the intake of red meat (eg., pork, beef).

Physical activity

Being physically active (performing regular exercise) lowers your blood pressure keeping your heart and arteries healthy. Physical activity also helps to keep your weight in check, lowering the risk of diabetes and obesity.1


Being overweight compels the heart to work harder to circulate blood around your body, which in turn leads to high blood pressure.1 Excess weight can cause build-up of fatty material in your arteries. If the arteries which carry blood to your heart get damaged and clogged, it can lead to a heart attack.4 Visceral fat (fat around the centre of your body/abdomen) raises the blood cholesterol levels and blood pressure, thus increasing the risk of developing Type 2 Diabetes (increased weight impairs efficient glucose circulation, resultant increased blood glucose levels which also damage the arteries) which are all closely linked to heart and circulatory diseases. 4 Therefore, it is important to ensure that one keeps their weight in check by eating a health diet and constant physical activity. 


It is important to not exceed the following recommended limits:

  • Men and women are advised not to exceed 14 units of alcohol a week.
  • It is advised to be avoid consuming many units of alcohol in one sitting or a day (evenly distribute drinking over 3 or more days if you consume 14 units of alcohol a week).1

It is essential to be mindful of your alcohol intake, regularly exceeding the recommended limits increases your blood pressure and cholesterol levels.1 Drinking a large volume of alcohol in a short period of time causes a dangerous sudden and large rise in blood pressure.1

Research has shown that people who have previously experienced a heart attack and continue to consume large amounts of alcohol in a short period of time are twice as likely to die from a serious health condition compared to people who drink moderately and are mindful of their intake after having a heart attack.1


Fluids are vital for normal bodily function, including efficient heart pumping, supporting blood vessel function and orchestrating circulation.5 Dehydration results in decreased blood volume levels and increased sodium retention, makes the blood viscous (thick) and developing an increase in the heart rate and blood pressure. 5


Sleep is essential for normal body functioning and good health. Adults are recommended to get at least 6-7 hours of sound sleep every night, as poor sleep patterns over time can lead to serious health problems.6 Lack of sleep is linked to high blood pressure (when we sleep, our blood pressure reduces), Type 2 diabetes (sleep improves blood sugar control) and obesity (insufficient sleep leads to unhealthy weight gain and hormone imbalance).6

Mental health

Biological and chemical factors which trigger mental health issues like depression, anxiety disorders, personality disorders, bipolar disorder, psychosis and schizophrenia also influence heart and circulatory diseases.7 Mental health conditions alter body hormone levels (adrenaline and cortisol) which impacts blood pressure and heart rate. It is important to seek professional help to manage your symptoms with medication and/or counseling if you or someone you know is suffering from mental health problems. 


Keeping your emotional health balanced is necessary for your physical health. Self-care is important for overall good health.

The most effective way to prevent a heart attack is by making active lifestyle changes - eating healthy, exercising regularly, getting good quality sleep, controlling your smoking and alcohol consumption, managing stress, getting regular health check-ups and taking active steps to improve your mental and physical health. Do not ignore the symptoms shown by your body and make sure to consult a professional at the earliest to ensure you can start counseling and treatment if required.


Heart attack occurs when oxygen-rich blood flow to the heart is suddenly blocked leading to muscle death if not treated quickly. Prompt medical treatment and making effective lifestyle changes can prevent or limit heart muscle damage, decreasing the chances of long-term health conditions. Getting regular check-ups to rule out the possibility of a heart problem is important. Contact your doctor immediately if you or someone you know may be having a heart attack.

Diagnostic testing

At Klarity we use the latest technology when it comes to diagnostic testing. Our home blood tests give you health insights and personalised recommendations. Find out which test you should take.


  1. Heart attack [Internet]. nhs.uk. 2017 [cited 2022 Oct 13]. Available from: https://www.nhs.uk/conditions/heart-attack/
  2. What is a heart attack? [Internet]. www.heart.org. [cited 2022 Oct 13]. Available from: https://www.heart.org/en/health-topics/heart-attack/about-heart-attacks
  3. Cardiovascular diseases (Cvds) [Internet]. [cited 2022 Oct 13]. Available from: https://www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds)
  4. Heart attack [Internet]. British Heart Foundation. [cited 2022 Oct 13]. Available from: https://www.bhf.org.uk/informationsupport/conditions/heart-attack 
  5. The importance of water [Internet]. The Heart foundation . [cited 2022 Oct 13]. Available from: https://theheartfoundation.org/2019/03/08/the-importance-of-water/ 
  6. CDC. How does sleep affect your heart health? | cdc. Gov [Internet]. Centers for Disease Control and Prevention. 2021 [cited 2022 Oct 13]. Available from: https://www.cdc.gov/bloodpressure/sleep.htm
  7. Mental health and heart health [Internet]. www.heart.org. [cited 2022 Oct 13]. Available from: https://www.heart.org/en/healthy-living/healthy-lifestyle/mental-health-and-wellbeing/mental-health-and-heart-health

Hannah Khairaz

BSc Biomedical Sciences Student, University College London

Hannah Khairaz is passionate about health, research, medical writing and educating the public about current advancements in medicine.

my.klarity.health presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
Klarity is a citizen-centric health data management platform that enables citizens to securely access, control and share their own health data. Klarity Health Library aims to provide clear and evidence-based health and wellness related informative articles. 
Klarity / Managed Self Ltd
Alum House
5 Alum Chine Road
Westbourne Bournemouth BH4 8DT
VAT Number: 362 5758 74
Company Number: 10696687

Phone Number:

 +44 20 3239 9818