The most basic function of the cardiovascular (or circulatory) system is to pump and distribute blood around the body. The cardiovascular system supplies all organs and tissues with oxygenated and nutrient-rich blood, while also removing any waste products within cells. Along with blood, the cardiovascular system also transports other vital substances like nutrients, hormones and immune cells.
What is the cardiovascular system?
Every part of the body relies on a steady flow of life-giving blood. The cardiovascular system comprises the heart, blood vessels (as arteries and veins) and blood. The heart works as a pump and beats regularly to send oxygen rich blood into the arteries which then carry the blood around the body. The arteries then divide into tiny capillaries where oxygen, nutrients, and other substances can pass through to surrounding cells and tissues.
What is blood?
Roughly 50% of blood is plasma - 90% of which is water - and the adult body has around five litres of blood. Plasma is made up of dissolved substances such as glucose, hormones, enzymes and waste products like urea and lactic acid. Plasma also contains proteins such as albumins, fibrinogen and globulins. The remaining 50% of blood is made of up three types of specialised cells- red blood cells (carry oxygen), white blood cells (defence and immunity) & platelets (involved in blood clotting).
The heart is a powerful organ located just to the left of centre in between the lungs and operates as two coordinated pumps to send blood around the body. The heart’s functions are complex, but if we try to simplify the process, this is what we get:
The heart is dynamic and precise, it adjusts the pumping mechanism that forces blood around the body’s immense network of blood vessels. The heart’s synchronisation is controlled by electrical impulses and acts as a natural pacemaker. There are four valves that control blood flow and the heart operates on dual circulation as the right side pumps blood to the lungs to be re-oxygenated and the left side pumps oxygen rich blood to all of the body tissues. This is just an overview and there is a lot more complexity to the heart, giving people an idea of just how important a healthy heart is regarding peoples health and wellbeing.
Disorders of the cardiovascular system may affect the heart itself - which can cause structural damage and disruption to the hearts rhythm - and/or blood vessel complications.
Some of the common cardiovascular disorders include:
Heart attack - A blockage of blood flow in the coronary artery affecting the heart muscle.
Angina - Tight, restricting chest pain caused by a temporary and inadequate supply of blood to the heart muscle.
Atherosclerosis - Build up of fats and cholesterol in the blood and artery walls.
Valve disorders - Narrow valves Caused by infection and as a result of the ageing process. The heart valves may not close completely, allowing back flow of blood into the heart’s chambers.
Embolism - A mobile clot, part of a thrombus and can block an artery and form clots in or near the heart or lungs leading to inadequate oxygen to target tissues.
Thrombosis - Blockage of a blood vessel by blood clot.
Arrhythmia - Heart rate that is unusually slow or fast, irregular or erratic
Hypertension - The increasing amount of pressure exerted in the heart and blood vessels as the heart pump blood around the body.
Promotion of cardiovascular health
As you can see from the above information, the cardiovascular system is necessary for human survival and is especially important to keep a close eye on regarding our mob and broader Australian population.
Some of the following strategies may allow for promotion and prevention in your cardiovascular health:
Limiting/avoiding cigarette smoking
Exercise (at least 150 minutes a week of light to moderate activity)
Managing your social and emotional (mental) health
Getting between 7-9 hours of good quality sleep each night
Staying in a healthy weight range, maintaining a BMI less than 25kg/m2 and a waist circumference <94 cms (in men) and <80 cms (in women)
Lowering you blood pressure if it is high by watching your salt intake
Choose healthy dietary fat options such as nuts, seeds, avocados and their oils for cooking and to apply on salads
Lowering LDL cholesterol and eating foods high in dietary fibre
The heart foundation is a fantastic resource for education, recipes and advice.