Heart attack: Symptoms, Causes, Treatment & Prevention

 

When an artery that supplies the heart with blood and oxygen becomes blocked, a heart attack happens. Over time, deposits of fat and cholesterol accumulate in the heart's arteries to form plaques. Plaque ruptures can result in the formation of a blood clot. A heart attack may result from the clot blocking arteries. The heart muscle tissue dies during a heart attack due to a reduction in blood flow.

A myocardial infarction, also known as a heart attack, is a medical emergency in which your heart muscle starts to die from inadequate blood flow. This is typically brought on by a blockage in the arteries that supply blood to your heart. A heart attack can result in death and permanent heart damage if medical professionals do not act quickly to restore blood flow. A heart attack must be treated quickly to avoid death.

Also Read: Blood Clotting Disorder: Symptoms, Causes, Diagnose & Treatment

What is heart attack?

A myocardial infarction, also known as a heart attack, is an extremely dangerous condition that occurs when there is insufficient blood flow to certain parts of the heart muscle. A blockage in one or more of your heart's arteries is typically the cause of this lack of blood flow, though there are other possible causes as well.

The damaged heart muscle will start to die without blood flow. If blood flow is not restored quickly, a heart attack may result in death or permanent heart damage.

A heart attack is a potentially life-threatening situation if you believe you or someone you're with is having a heart attack  When treating a heart attack, time is of the essence. Even a few minutes of delay can cause death or permanent heart damage.

Symptoms:

Heart attack symptoms are not all the same. Some people only have minor symptoms. Others' symptoms are severe. Some people don't exhibit any symptoms.

Typical signs of a heart attack include:

• The sensation of pressure, tightness, pain, squeezing, or aching in the chest

• Pain or discomfort that radiates to the neck, jaw, teeth, shoulder, arm, back, or occasionally the upper abdomen

• Cold sweat 

• Fatigue

• Indigestion or heartburn

• Dizziness or sudden lightheadedness

•  Nausea

• Shortness of breath

Women may experience unusual symptoms such as sudden, severe pain in the back, arm, or neck. Sudden cardiac arrest can occasionally be the initial sign of a heart attack.

Some heart attacks happen all at once. However, many people exhibit symptoms and warning signs hours, days, or weeks. An early warning sign could be persistent chest pain or pressure (angina) that doesn't go away with rest. Angina is caused by a brief reduction in heart blood flow.

Causes:

 Most heart attacks are caused by coronary artery disease.  One or more of the heart's (coronary) arteries are blocked in coronary artery disease.  Plaques, which are deposits that contain cholesterol, are typically the cause of this.  The arteries may narrow due to plaque, which would lower heart blood flow.

 A blood clot in the heart may result from a plaque breaking open.

 A heart (coronary) artery blockage, whether total or partial, can result in a heart attack.  If an electrocardiogram (ECG or EKG) exhibits certain abnormalities (ST elevation) that call for immediate, invasive treatment, that can be used to categorize heart attacks.  The results of your electrocardiogram (ECG) may be used by your healthcare provider to describe these heart attack types.

An ST elevation myocardial infarction (STEMI) is typically indicated by an acute total blockage of a medium or large heart artery.
It is common to have a partial blockage if you have experienced a non-ST elevation myocardial infarction. Nonetheless, a complete blockage occurs in certain patients with non-ST elevation myocardial infarction (NSTEMI).

Blocked arteries are not the cause of every heart attack. Other reasons are as follows:

• Spasm of the coronary artery A blood vessel that is not blocked is being severely squeezed. Cholesterol plaques or early vessel hardening from smoking or other risk factors are common in arteries. Variant angina, vasospastic angina, and Prinzmetal's angina are other names for coronary artery spasms.

• Specific infections. Viral infections, including COVID-19, have the potential to harm the heart muscle.

• Spontaneous coronary artery dissection (SCAD). A tear inside a heart artery is the cause of this potentially fatal condition.

Risk factors:

 Risk factors for heart attacks include:

• Age.  Compared to younger men and women, heart attacks are more common in men aged 45 and over and in women aged 55 and over.

• Use of tobacco.  Both smoking and prolonged exposure to secondhand smoke fall under this category.  Give up smoking if you do.

• High blood pressure.  High blood pressure can harm the arteries that supply the heart over time.  The risk is further increased when high blood pressure coexists with other illnesses like diabetes, high cholesterol, or obesity.

• High levels of triglycerides or cholesterol. Arteries are most likely to narrow when low-density lipoprotein (LDL) cholesterol—the "bad" cholesterol—is present in high concentrations. The risk of a heart attack is also increased by high levels of triglycerides, which are specific blood fats. If your levels of the "good" cholesterol, known as high-density lipoprotein (HDL), are within the normal range, your risk of having a heart attack may decrease.

• Being overweight. Obesity is linked with high blood pressure, diabetes, high levels of triglycerides and bad cholesterol, and low levels of good cholesterol.

• Diabetes. Blood sugar rises when the body doesn't make a hormone called insulin or can't use it correctly. High blood sugar increases the risk of a heart attack.

• Metabolic syndrome. This is a combination of at least three of the following: high blood pressure, low good cholesterol, high triglycerides, high blood sugar, and an enlarged waist (central obesity). Your chances of developing heart disease are doubled if you have metabolic syndrome.

• Heart attacks in the family history. You may be at higher risk if a parent, grandparent, brother, or sister experiences an early heart attack (by age 65 for women and by age 55 for men).

• Not enough exercise. A sedentary lifestyle, or lack of physical activity, is associated with an increased risk of heart attacks. Heart health is improved by regular exercise.

• Unhealthy diets. The risk of heart attacks is increased by a diet heavy in processed foods, animal fats, sugars, trans fats, and salt. Consume a lot of fiber, fruits, vegetables, and healthy fats.

• Stress. Extreme anger and other emotional stressors can raise the risk of a heart attack.

• Illegal use of drugs. Amphetamines and cocaine are stimulants. They may cause a heart attack by causing a coronary artery spasm.

• A preeclampsia history. During pregnancy, this condition results in high blood pressure. It raises the risk of heart disease throughout life.

• An autoimmune disease. A heart attack is more likely to occur in people who have lupus or rheumatoid arthritis.

Complications:

Damage to the heart muscle is frequently the cause of heart attack complications. The following are possible heart attack complications:

• Heart rhythms that are abnormal or irregular (arrhythmias). Damage from a heart attack may alter the way electrical signals pass through the heart, changing the rhythm of the heartbeat. Some could be deadly and quite serious.

• Cardiac shock. This uncommon disorder develops when the heart's ability to pump blood is suddenly and abruptly compromised.

• Heart failure. The heart may not be able to pump blood if there is significant damage to the heart muscle tissue. There are two types of heart failure: acute and chronic.

• Pericarditis, or inflammation of the sac-like tissue encircling the heart. A malfunctioning immune system reaction can occasionally be brought on by a heart attack. Dressler syndrome, postmyocardial infarction syndrome, postcardiac injury syndrome are some names for this condition.

• Cardiac arrest. The heart suddenly stops beating. Sudden cardiac arrest is brought on by an abrupt alteration in the heart's signaling. This potentially fatal condition is more likely to occur after a heart attack. If treatment is delayed, it may result in sudden cardiac death.

 Diagnosis:

How can I tell if I've experienced a heart attack?

Heart attacks are typically diagnosed by medical professionals in an emergency department. You should be examined physically if you are experiencing the symptoms of a heart attack. A healthcare professional will listen to the sounds of your heart and lungs, and check your blood pressure, pulse, and oxygen levels. They will also ask about your symptoms. Someone who was with you may be asked to explain what happened.

To diagnose a heart attack, what tests will be performed?

A medical professional will use the following to diagnose a heart attack:

• Blood tests. A blood test for cardiac troponin is one of the most accurate methods of diagnosing a heart attack. This chemical marker always shows up in your bloodstream during a heart attack because of the damage to the heart muscle cells.

• EKG or ECG stands for electrocardiogram. When you arrive at an emergency room with symptoms of a heart attack, this is one of the first tests you will receive. The electrical signals from your heart can be used to determine whether an injury is happening and whether there are any abnormalities in its rhythm.

• Echocardiogram. An echocardiogram uses high-frequency sound waves, or ultrasound, to create a picture of your heart both inside and outside. It can demonstrate how well the valves are functioning and how well your heart is pumping.

• Heart catheterization or coronary angiography. This procedure can assist in identifying any blockages by using X-rays and contrast dye to show the blood vessels leading to your heart.

• Heart computed tomography  (CT) scan. This produces an extremely detailed scan of your heart and blood vessels to determine whether the major coronary arteries have significantly narrowed or hardened.

• Magnetic resonance imaging (MRI) of the heart. This test creates an image of your heart using computer processing and a strong magnetic field. It may indicate issues with the heart's arteries' ability to pump blood.

• Perform a stress test. This test can determine whether your heart is getting enough blood flow by using an ECG, echocardiogram, or nuclear scan while you are exercising.

• Scans of the nuclear heart. These scans use computer-enhanced techniques like computed tomography (CT) and a radioactive dye that a healthcare provider injects into your blood to identify damaged or under-supplying areas of your heart. These scans may be positron emission tomography (PET) scans or single-photon emission computed tomography (SPECT) scans.

How do you treat a heart attack?

Restoring blood flow to the damaged heart muscle as soon as possible is the goal of treating a heart attack. Numerous methods, from medication to surgery, can cause this. Several of the following techniques will probably be used in the course of treatment.

Supplemental oxygen is frequently given to patients experiencing dyspnea or low blood oxygen levels in addition to other heart attack treatments. Either a mask that covers your mouth and nose or a tube that rests just below your nose can be used to breathe the oxygen. This lessens the strain on your heart and raises the amount of oxygen in your blood.

Medications

These could consist of:

• Anti-clotting medications. Aspirin and other blood-thinning medications fall under this category.

• Nitroglycerin. In addition to relieving chest pain, this medication widens blood vessels to facilitate easier blood flow.

• Thrombolytic medications, which break up clots. These are only used by providers in the first twelve hours following a heart attack.

•  Antiarrhythmia medication. Arrhythmia, which are potentially fatal disruptions in the heart's regular beating rhythm, are frequently brought on by heart attacks. These malfunctions can be stopped or prevented with antiarrhythmia medications.

• Medication for pain. Morphine is the most often prescribed painkiller for heart attack patients. Chest pain may be lessened by doing this.

• Beta-blockers. For your heart to heal from the damage caused by a heart attack, these medications help by lowering your heart rate.

• Medications that lower blood pressure. These drugs can help your heart heal from the damage caused by a heart attack and lower your blood pressure.

• Statins. These medications lessen the chance of your heart's blood vessels rupturing by stabilizing the plaque there. Additionally, they lower cholesterol and the risk of another heart attack.

Percutaneous coronary intervention:

 A procedure known as percutaneous coronary intervention (PCI) or angioplasty is used by providers to restore circulation to the damaged heart muscle.

 To restore blood flow, opening your artery with a catheter is essential.  The likelihood of a successful outcome increases with the timing of that.  A measure known as "door-to-balloon time" is used by providers to assess their capacity to treat a heart attack.  This is the typical amount of time that patients spend in the emergency room before undergoing PCI.  Your doctor might implant a stent at the blockage site if you are given PCI.  In order to prevent another blockage from occurring in the same location, the stent helps keep your artery open.

Grafting a coronary artery bypass:

Coronary artery bypass grafting (CABG) may be necessary for patients with severe coronary artery blockages. Providers often call this open-heart surgery or bypass surgery.

In CABG, a blood vessel from another part of your body—typically your arm, leg, or chest—is used to create a blood detour. This brings blood to your heart muscle by rerouting it around one or more blocked artery sections.

Prevention:

Even if you've already experienced a heart attack, there's always time to take preventative measures. Here are some strategies to avoid having a heart attack.

• Scheduling for a check-up. Locate a primary care physician (PCP) and schedule a wellness visit or checkup with them at least once a year. Many of the early warning signs of heart disease, including imperceptible changes, can be detected during an annual physical. These consist of your blood pressure, cholesterol, blood sugar, and other measurements.

• Giving up tobacco products. This covers all vaping products as well as smokeless tobacco.

•  Regular exercise. Every day of the week, try to get in 30 minutes of moderately challenging physical activity.

• Consuming nutritious meals. The Mediterranean and Dash diets are two examples. Consuming plant-based foods is a great way to cut back on processed meats and saturated fats.

• Keeping your weight within a healthy range. Your primary care physician can help you determine a healthy target weight and offer you the tools and direction you need to get there.

• Reducing your level of stress. Think about methods like meditation, yoga, and deep breathing.

• Taking prescription medication as directed. Don't only take your medications when you remember to or when you have an upcoming visit with your doctor.

• Attending all of your appointments with doctors.  Regular visits to your healthcare providers can help identify medical conditions you were unaware you had, such as heart-related problems.  Additionally, this can help address issues early on.

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