How Sudden Heart Attacks Happen: Symptoms, Causes, and Daily Prevention Tips

Acute Myocardial Ischemia, commonly referred to as a sudden heart attack, is a medical emergency that can lead to death within an hour of symptom onset if not promptly treated.

The Department of Medical Services in Thailand has issued strong warnings to the public: if you experience symptoms such as chest tightness, unusual sweating, palpitations, jaw or arm pain, or a sensation of pressure under the breastbone, it is critical that you seek medical attention without delay. Early recognition and rapid response can mean the difference between life and death.

The condition is primarily caused by a sudden blockage in the coronary arteries due to a blood clot. This blockage cuts off the oxygen-rich blood supply to a portion of the heart muscle, which can cause irreversible damage or death of the heart tissue if not treated immediately. The result is often a heart attack, and in severe cases, sudden cardiac death.

What Causes Acute Myocardial Ischemia?

Dr. Narong Apikulvanich, Deputy Director-General and spokesperson of Thailand’s Department of Medical Services, explains that the root cause of acute myocardial ischemia is often coronary artery disease (CAD). This occurs when a clot forms and blocks the coronary arteries, which are responsible for supplying blood and oxygen to the heart muscle.

The coronary arteries can become narrowed or hardened due to atherosclerosis, a condition where fatty deposits (plaque) accumulate on the artery walls. Over time, these plaques may rupture. When they do, the body responds as it would to any injury: by forming a blood clot. However, this clot can fully block the artery, suddenly halting the blood supply to a part of the heart. Without oxygen and nutrients, the heart tissue begins to die—resulting in a heart attack.

The Alarming Statistics in Thailand

In Thailand, statistics show that 45% of sudden deaths are caused by coronary artery disease. This is particularly alarming because, in many cases, individuals may have no previous symptoms or history of heart disease. These heart attacks can occur without warning during routine daily activities like working, walking, or even sleeping.

What makes coronary artery disease especially dangerous is its silent progression. People may feel perfectly fine while plaque builds up in their arteries over many years. Then, in a single moment, a plaque ruptures and triggers a fatal heart attack. This emphasises the need for proactive health monitoring and lifestyle adjustments, even among people who believe they are healthy.

Who Is at Risk?

While anyone can be affected by heart disease, some groups are at higher risk than others. These include:

• People over the age of 40

• Individuals with a family history of heart disease

• Smokers

• People who are overweight or obese

• Individuals with high blood pressure, high cholesterol, or diabetes

• Those with sedentary lifestyles or chronic stress

For these individuals, routine health screenings and lifestyle changes are essential.

Symptoms and Warning Signs to Never Ignore

Recognising the symptoms of acute myocardial ischemia is crucial for survival. Some of the most common warning signs include:

• Chest tightness or pain: Often described as pressure, squeezing, or fullness in the chest.

• Excessive sweating: Especially cold sweat that isn’t caused by heat or exertion.

• Heart palpitations: A racing or irregular heartbeat.

• Pain radiating to other areas: Especially the jaw, left arm, back, neck, or shoulder blade.

• Shortness of breath: Difficulty breathing even while resting.

• Nausea or dizziness: Sometimes mistaken for indigestion or a stomach bug.

These symptoms can mimic less serious conditions such as acid reflux or muscle strain, which is why people sometimes delay seeking help. However, time is of the essence.

Medical experts recommend that treatment, whether through clot-dissolving medication or angioplasty with stent placement, should ideally occur within the first hour and no later than 3 hours after symptom onset to maximise survival chances and prevent permanent heart damage.

How to Reduce the Risk of Acute Myocardial Ischemia in Daily Life

While some risk factors such as age or family history are beyond control, there are many preventive measures that individuals can take to protect their heart:

1. Avoid High-Fat and High-Cholesterol Foods

Saturated fats found in red meats, butter, deep-fried foods, and full-cream dairy products contribute to plaque buildup in arteries. Instead, opt for heart-healthy foods such as:

• Fresh fruits and vegetables (aim for 5 servings a day)

• Whole grains like oats, quinoa, and brown rice

• Lean proteins such as chicken, tofu, legumes, and fish rich in omega-3 fatty acids

• Healthy fats from nuts, seeds, and olive oil

Reducing sodium intake is also important to help manage blood pressure.

2. Maintain a Healthy Weight

Being overweight increases the strain on your heart. When you’re heavier, your heart has to pump harder to circulate blood, which can weaken the heart muscle over time. Regular physical activity combined with portion control and mindful eating can help with weight management.

Doctors recommend:

• At least 150 minutes of moderate exercise per week, such as brisk walking, swimming, or cycling.

• Avoiding sugary drinks and processed foods that offer empty calories.

3. Manage Stress Effectively

Chronic stress can raise blood pressure, trigger arrhythmias, and increase the risk of heart disease. Take steps to manage stress through:

• Meditation or mindfulness practices

• Spending time with loved ones

• Gardening or hobbies that bring joy

• Limiting screen time and exposure to stressful news

4. Avoid Smoking and Limit Alcohol

Smoking damages the lining of your arteries and significantly increases the risk of blood clots. Quitting smoking is one of the single most impactful decisions you can make for your heart health.

Similarly, alcohol—especially when consumed in excess—raises triglyceride levels and can lead to irregular heartbeats or weakened heart muscles. Moderation is key: no more than one drink per day for women and two for men.

5. Control Underlying Health Conditions

For individuals with diabetes, hypertension, or high cholesterol, close medical management is critical. Keeping blood sugar and blood pressure within recommended ranges can significantly lower the risk of a heart attack.

• Monitor your numbers regularly

• Take medications as prescribed

• Stay informed about your health status through annual or bi-annual checkups

The Importance of Regular Health Check-Ups

Because heart disease can be asymptomatic for years, regular check-ups are essential for early detection. A routine physical exam can reveal:

• Elevated blood pressure

• Abnormal cholesterol levels

• Signs of diabetes

• Abnormal heart rhythms on ECGs

Some facilities offer cardiac risk assessments, which may include:

• Blood tests (lipid panel, glucose)

• ECG or stress testing

• Echocardiography or CT angiography if needed

Annual screenings are highly recommended for those over 40 or anyone with risk factors.

What Happens During a Sudden Heart Attack?

A heart attack, or myocardial infarction, begins when a plaque ruptures in the coronary artery. This rupture attracts platelets (a type of blood cell) to the site, and a clot forms to “seal” the rupture. Unfortunately, this clot also blocks blood flow.

Without blood, the affected part of the heart muscle starts dying within minutes. If the blockage occurs in a major artery, the entire left or right side of the heart can be compromised. This leads to:

• Sudden chest pain

• Loss of consciousness

• Cardiac arrest (heart stops beating)

Immediate intervention with thrombolytic drugs or angioplasty can restore blood flow and save the patient’s life. In the worst cases, sudden cardiac death can occur within minutes.

Final Thoughts: Prevention is Better Than Cure

Acute myocardial ischemia is a preventable yet life-threatening condition. It is called the “silent killer” for a reason—often striking people with no prior symptoms. But awareness, lifestyle changes, and timely medical intervention can turn the tide.

To protect yourself and your loved ones:

• Don’t ignore symptoms, no matter how mild they seem.

• Live a heart-healthy lifestyle—eat clean, move often, rest well, and manage stress.

• Quit smoking and drink in moderation.

• Monitor and manage chronic conditions diligently.

• Get annual check-ups, especially after the age of 40.

Remember: your heart health is in your hands. Take the right steps today to avoid sudden tragedy tomorrow.