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Heart BeatThe heart's electrical systemThe atria and ventricles work together, alternately contracting and relaxing to pump blood through your heart. The electrical system of your heart is the power source that makes this possible. Your heartbeat is triggered by electrical impulses that travel down a special pathway through your heart:
At rest, a normal heart beats around 50 to 99 times a minute. Exercise, emotions, fever and some medications can cause your heart to beat faster, sometimes to well over 100 beats per minute. How fast does the normal heart beat?How fast the heart beats depends on the body's need for oxygen-rich blood. At rest, the SA node causes your heart to beat about 50 to 100 times each minute. During activity or excitement, your body needs more oxygen-rich blood; the heart rate rises to well over 100 beats per minute. Medications and some medical conditions may affect how fast your heart-rate is at rest and with exercise. How do you know how fast your heart is beating?You can tell how fast your heart is beating (your heart rate) by feeling your pulse. Your heart-rate is the amount of times your heart beats in one minute. You will need a watch with a second hand. Place your index and middle finger of your hand on the inner wrist of the other arm, just below the base of the thumb. You should feel a tapping or pulsing against your fingers. Count the number of taps you feel in 10 seconds. Multiply that number by 6 to find out your heart-rate for one minute: Pulse in 10 seconds x 6 = \__ beats per minute (your heart-rate) When feeling your pulse, you can also tell if your heart rhythm is regular or not.
Normal Heart Beat1. The SA node sets the rate and rhythm of your heartbeat. 2. The SA node fires an impulse. The impulse spreads through the walls of the right and left atria, causing them to contract. This forces blood into the ventricles. 3. The impulse travels to the AV node. Here, the impulse slows for a moment before going on to the ventricles. 4. The impulse travels through a pathway of fibers called the His-Purkinje network. This network sends the impulse into the ventricles and causes them to contract. This forces blood out of the heart to the lungs and body. 5. The SA node fires another impulse. The cycle begins again. Get useful, helpful and relevant health + wellness information
enews More health news + infoWhen the heart contracts and forces blood into the arteries the pressure created is known as the Select one?The top number, or systolic pressure, refers to the pressure inside the artery when the heart contracts and pumps blood through the body. The bottom number, or diastolic pressure, refers to the pressure inside the artery when the heart is at rest and is filling with blood.
What is the pressure exerted on the walls of the arteries when the left ventricle contracts called?The systolic blood pressure is defined as the maximum pressure experienced in the aorta when the heart contracts and ejects blood into the aorta from the left ventricle (approximately 120 mmHg).
When obtaining a blood pressure the EMT listens for a pulse over what blood vessel?33. To determine blood pressure, the EMT should position the cuff over the upper arm and place the stethoscope over the brachial artery.
Which blood pressure measurement is the lower number that represents the amount of pressure on arterial walls when the heart relaxes?Diastolic blood pressure is measured when the heart ventricles relax. A systolic pressure of 115 millimeters of mercury is considered normal, as is a diastolic pressure of 70.
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