You may still remember our sheep's heart dissection. here are slides that may help recall our lesson and more. Recall the following concept when viewing these 38 slides:
blood circulation in body
blood flow through the 4 chambers of the heart
sheep's heart cut open,showing relative thicknesses of the atria, left ventricle and right ventricle, aorta, vena cava and pulmonary arteries and veins
diastole and systole, Wigglers diagram
cardiac cycle, about 0.7 sec, showing pressure changes in aorta, left atrium and left ventricle
large, diagram to show aorta and its supply to all organs of the body
pulmonary artery and how it supplies the alveoli
detailed annotated diagrams of arteries, veins and capillaries
some X-ray pictures to show path of blood in major blood vessels
(Mitral valve is the old name for bicuspid valves that you find in your textbooks.)
Yes, your heart can run on battery. Pacemakers are small electronic devices that regulate heartbeats and they run on battery.
Why have battery operated heart?
It can prevent stroke in the elderly.
It is fitted if the heartbeats are too slow or too fast or irregular. These arrhythmic heart beat can lead to stoke or even sudden death. Atrial fibrillation is when the upper heart chambers are not pumping blood into the lower chambers (ventricles) normally.
If the flow of blood out of the heart is slow, or sluggish, then blood will start to form clots or lumps. These lumps will then break off and move along the blood vessels and may block the blood to the brain causing stroke(brain attack), blood to the heart muscles causing heart attack or blood to the lungs causing breathing problems (lung attack).
Who can have pacemakers?
People who have fainting spells, near blackouts and breathlessness after walking. Pacemakers have been around for 50 years. More than 3,000 people in Singapore have them. The cheapest model is only $3000, when subsidised by the government. Each year about 75 people have pacemakers fitted into them in Singapore.
How does the pacemaker work?
The battery sends electrical signals to the atria to make them pump normally. If the ventricles are not working normally, a 2nd or 3rd wire can shock the heart to beat properly. This is called Implantable cardioverter defibrillator (ICD) If the heart stops beating, as in sudden deaths in athletes, the pacemaker will shock it into working too.
Is it true that pacemakers are affected by telecommunication devises? Yes. They have to keep away from mobile phones, microwaves, MP3 music players and airport electronic screening as they interfere with the battery's electrical signals.
What is AED?
Ambulance personnel are usually trained to use the Automated External Defibrillator or AED. It is simple to use to revive the heart that has stopped or has irregular heartbeat.
This is a portable light-weight electronic devise that is carried in most ambulances, fire and police vehicles. In Japan, it can be found in railway stations, shopping centres, health clubs and other places where sudden cardiac arrests may occur.
The sun is the ultimate source of energy that powers all food chains. Sunlight energy is captured by green plants and passed on to the other organisms along the food chains. Without this original (asal) energy there will be no energy to power (sakti) ecosystems.
The painting at top shows how Man and his machines could easily destroy the delicate and beautiful balance of Nature, which we can crush as easily as soap bubbles.
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