Heartbeats Primer on Heart Disease and Heart Health
Q&A
What is heart disease?
Heart disease is a general term that covers the condition of your heart (the ‘pump’), or the arteries to your heart (the ‘piping’).
The conditions that can affect how your heart functions are:
- the operation of the valves in your heart, which allow the heart to pump blood properly,
- the electrical signals that regulate your heartbeat, or
- the structure of your heart (the heart muscle and chambers).
What is a heart attack?
There are two general events that are generally known as a heart attack.
One is when a blood clot is released from the rupture of plaque build up in your arteries, which is carried to either the heart or the brain where it blocks a blood vessel in either of these organs, which starves them of blood and oxygen. This can cause damage to that area and results in severe pain and/or breathlessness (if in the heart) or stroke (if in the brain). In this event, you are usually conscious.
The second is where the electrical pulses that cause the heart to beat rhythmically, are interrupted or stopped and this leads to unconsciousness and what is known as cardiac arrest.
What is arrythmia and how do I know?
An arrhythmia is an unusual heartbeat that is either much faster or slower than expected. Your heartbeat may be described as chaotic, rather than steady and predictable. This is called ‘fibrillation’.
There are several types of arrhythmias. Some are much more dangerous than others. Arrhythmias that originate in the ventricles — your heart’s two lower chambers — are especially dangerous.
What is an Angiogram?
When you have blocked arteries, called ‘cardiovascular disease’ (CVD) you will often get chest pain (‘angina’) if the blockage is in your coronary arteries. your heart is starved of oxgen and blood flow.
Your doctor will refer you to have an X-ray picture taken of your heart and the arteries around it (‘angiogram’). This involves injecting a dye into your blood which shows up any blockages or narrowing of your arteries.
You will also be sent for an angiogram if you have had a heart attack.
What is a stent and how does it work?
A stent is a very small metal mesh tube that is inserted into your artery where it is narrowed by plaque buildup, to hold it open and unblock it. The stent is put in, collapsed around a hollow wire, called a catheter, which has a small balloon at the end.
When the balloon is inflated by air, it opens the stent and pushes it up against the walls of your artery at the blockage. expanding the artery back to its normal diameter again. When the balloon is deflated and the catheter is withdrawn, the stent remains in place, holding the artery open.
The process of putting in a stent is called angioplasty.
What is blood pressure?
When your heart beats it pumps blood to your body through a network of blood vessels called arteries, pushing against the artery walls. The strength of this ‘pushing’ is your blood pressure.
High blood pressure (‘hypertension’) is when the force on your artery walls is higher than what is recommended as being safe. High blood pressure can damage your arteries and increase your risk of heart attack, stroke, heart failure, kidney and eye- damage.
Blood pressure is measured as two numbers: the higher one is when the heart is pumping blood into your arteries (systolic) and the other when it is relaxed between beats (diastolic).
An ideal blood pressure is 120/80 but it increases as your get older, particularly over the age of 65.
The target blood pressure for people who are taking medications (drugs) for lowering blood pressure is 130/80.
Blood pressure over 150/90 is extreme and you should see your doctor.
You are likely to get high blood pressure if you:
- eat too much salt or processed foods
- smoke
- are stressed
- are overweight
- don’t exercise
- have diabetes or kidney disease
- have a parent who has had high blood pressure (‘family history’)
What is atherosclerosis?
Atherosclerosis is the build-up of fatty deposits (called plaque) on the walls of your arteries, which block the flow of blood through them. Our blood carries oxygen which fuels the operation of our cells and muscles.
A blockage in an artery to the heart, stops the heart from receiving enough oxygen for it to work.
Also, sometimes the build-up of plaque can rupture or break, and this releases a clot which could travel to the heart where it might completely block an artery and cause a heart attack, or to the brain, where it causes a stroke.
What is heart disease risk and how is it measured?
The likelihood of getting heart disease and of having a heart attack can be measured by using an equation that takes into account things like: family history, weight and height (body mass index), if you are a smoker, how much regular exercise you do.
All these ‘risk factors’ are taken into account and produce a final number, which is usually expressed as a risk percentage i.e. 10% means that out of 100 people, 10 people who all have the same factors as you, will have a heart attack within five years.
What natural foods are good for my heart?
Some natural foods can produce some of the same positive effects as prescription drugs. However, they cannot produce the full effect as approved drugs and should be considered as additional help but not replace your medication.
For example, broccoli, turmeric and XX have been proven to help reduce blood pressure while the fish oil in salmon or sardines helps reduce cholesterol.
How does exercise help my heart?
Research has shown that regular, daily brisk walking (where you are breathing moderately but not breathless) is very beneficial for your heart and has as much positive impact on avoiding another heart attack as many of the drugs that you have to take.
Your heart is a big muscle, which has to pump over 1.1 billion times in your lifetime, and like any muscle, it needs to be exercised to keep it strong.
Also, brisk walking and other exercise, pumps more oxygen around your body and burns fat, which is then removed from your bloodstream, and cannot build up as plaque on the walls of your arteries.
Exercise keeps you fit, creates healthy cells (including heart cells), helps keep your blood pressure stable, and lowers stress. Stress has been shown to be a major factor in heart disease.
What is the difference between heart attack and cardiac arrest?
Cardiac arrest is when the heart stops completely, and the person loses consciousness.
Heart attack is when the heart is starved of oxygen because of blockage in the arteries around the heart (the coronary arteries) so that not enough blood gets to the heart and not enough oxygen for the heart muscles to work.
How much can I lift, and how much exercise can I do after heart surgery or a stent?
After heart surgery or a stent, it is important to understand that you have had serious treatment for a major condition that has affected your heart.
Therefore, while your heart and your cardiovascular (coronary arteries) system is recovering and becoming strong again, you must ease gradually back into the sorts of physical activities that you might have done in the past.
While recovering, it is not uncommon to find that even something as simple as walking to the end of your block might make you tired and a little breathless. It is important to talk to your doctor about any recovery issues that bother you.
For up to six weeks after surgery, you shouldn’t lift more than about two kilograms (2kg, about a 2L jug of milk) in each hand – lifting a bag of groceries is generally fine. You should not lift moderate-heavy weights that strain your upper body.
For the first 12 weeks it is best to engage in aerobic exercise (brisk walks, light jog or non-strenuous workout on an exercycle) while gradually increasing strength and weight exercises. You should always consult with your doctor or discuss how you plan to exercise, with a qualified physiotherapist, before launching into exercise programme.
Are certain drugs that my doctor has prescribed, more important than others and does it matter if I miss some of the ones that are not important?
All drugs that you are prescribed by your doctor are important in that they each treat different aspects of your heart condition. For example, for cardiovascular disease (build- up of plaque on the walls of your arteries) your doctor will usually prescribe:
- a blood thinner – your blood flows more easily which reduces the strain on your heart and arterial walls
- a statin – which reduces your cholesterol levels (particularly your bad cholesterol or LDL) so that you are less likely to build more plaque and makes the plaque that you have, less likely to break loose a clot
- a drug that either relaxes the heart (beta-blocker) so that it doesn’t have to work so hard, or
What is cholesterol and what are the target levels?
Cholesterol is a type of fat that circulates in the blood. It performs a number of important functions in helping your cells work.
There are two types of cholesterol: high-density (HDL) and low-density (LDL). The low-density cholesterol is the ‘bad’ cholesterol.
Three quarters (75%) of your cholesterol is made in your liver and not as much dependent on what you eat.
You need to have a blood test to find out what your cholesterol levels are.
Before a heart event, your target cholesterol levels for LDL are 2.4, but after a heart event your doctor will try to get it down to 1.7.
Overall, a healthy TOTAL cholesterol target (for HDL + LDL) is 3.5 with a maximum of 5.0.
What is Valve Disease?
Your heart has four chambers that receive and send blood to your lungs and the body.
Disorders affecting your heart valves can be narrowing (‘stenosis’) or backwards leakage after the valve has closed (“regurgitation’).
These disorders make the heart pump less efficiently. They can be picked up by your doctor listening for heart murmurs, or by an ultrasound of your heart (‘echocardiogram’).