Answer:
I'm still trying to figure that out for my self
The Centers for Disease Control
2. When the left ventricle relaxes, the aortic valve closes and the mitral valve opens. This lets blood flow from the left atrium into the left ventricle.
4. Quickly shocking the heart with an automated external defibrillator (AED) can save a person's life after cardiac arrest. An AED is a portable, battery-operated device that a bystander can use. It checks the heart rhythm and can send an electric shock to the heart to try to restore a normal rhythm.
5. High blood pressure can damage your arteries by making them less elastic, which decreases the flow of blood and oxygen to your heart and leads to heart disease. In addition, decreased blood flow to the heart can cause: Chest pain, also called angina.
hope this helps :)
