By Dr Pankaj Kshatriya, MD (Physician)
How the heart works
To understand heart disease, you must first know how the heart works. The heart is like any other muscle, requiring blood to supply oxygen and nutrients for it to function. It beats about 100,000 times a day, pumping blood through your circulatory system. The cycle of pumping blood throughout your body carries fresh oxygen to your lungs and nutrients to your body’s tissues.
What is heart disease?
Heart disease begins when cholesterol, fatty material and calcium pile up and clog the arteries. When this happens to the arteries that supply the heart, this build-up, or plaque, causes the arteries to narrow, so that oxygen delivery to the heart is reduced. The reduction in oxygen delivery to the heart can lead to chest pain, which is also called angina.
The link between heart disease and heart attack
When plaque builds up to the point that it ruptures, it causes a blood clot to form in the coronary artery. The blood clot blocks blood from flowing to the heart muscle, leading to a heart attack. In a worst-case scenario, sudden cardiac arrest or fatal rhythm disturbance can occur.
What are the risk factors for heart disease?
Some of the common risk factors for heart disease include:
– Smoking
– High blood pressure (Hypertension)
– High cholesterol
– Diabetes
– Family history of heart disease
– Peripheral artery disease
– Obesity
What are the lifestyle risk factors for heart disease?
The lifestyle risk factors that contribute to heart disease include:
– Lack of exercise
– High-fat diet
– Emotional stress
– Having a ‘Type A’ personality (Aggressive, impatient, competitive)
Sudden cardiac death
Everyone’s experience with heart disease is different. Some people experience shortness of breath or chest pain and make it to the hospital in time to be treated. Others are not as lucky. For some people, sudden cardiac arrest can be the first symptom they experience and it is often deadly unless treated immediately.
What are the common symptoms of heart disease?
The symptoms of heart disease usually occur during exercise or activity. That’s because the heart experiences increased demand for nutrients and oxygen that cannot be met because the coronary arteries are blocked. The principal symptoms of heart disease include:
– Chest pain (angina)
– Shortness of breath
– Jaw pain
– Back pain, especially on the left side
Other symptoms may include:
– Dizziness or light-headedness
– Weakness when at rest
– Irregular heartbeat
– Nausea
– Abdominal pain
Symptoms in women and people with diabetes
For many women and people with diabetes, pain is not a symptom of heart disease at all. Instead of experiencing discomfort, they often have symptoms of malaise or fatigue.
What is an electrocardiogram (EKG)?
A healthy heart works as an ‘electrical pump’ and needs a strong blood supply to conduct electricity. People with heart disease, however, have a poor blood supply, so their heart conducts electricity poorly. An electrocardiogram (EKG) is a non-invasive test that measures the electrical activity of the heart. An EKG takes approximately five minutes and is painless.
Many other heart conditions can be diagnosed with an EKG, for example:
– Abnormal heart rhythms
– Evidence of a prior heart attack
– Evidence of an evolving heart attack
– Unstable angina
– Congenital heart abnormalities
– Evidence of abnormal blood electrolytes
– Evidence of inflammation of the heart (myocarditis, pericarditis)
What is echocardiography?
Doctors may want to use echocardiography to detect heart disease. Echocardiography uses sound waves to generate images of the heart. The test serves as a tool to see how well the heart muscle is functioning. A normal heart pushes at least 50-60% of the blood in the ventricle out to the body when it beats. Echocardiography can show if the heart muscle is weaker than this, which could indicate heart disease.
(To be continued)
