1. Warmup 3/1/16 What kind of heart rate is good? What does heart rate mean? Objective Tonight’s Homework To learn about heart beat and heart rate pp 567: facet 21A-2: 1, 2, 3

2. Heart Rate and Blood Pressure The rate at which your heart beats is controlled by several things. The heart has 2 stages: - Relaxed, or diastolic, where blood is filling into the atria. - Contracting, or systolic, where blood is being pumped from the ventricles into blood vessels. Between these two is a brief period where blood drains from atria into ventricles.

3. Heart Rate and Blood Pressure Your heart pumps due to the action of the sinoatrial (or SA) node. This is a specialized tissue that controls how often your heart contracts. When this tissue fires, the rest of the myocardial tissue contracts, starting the systolic action.

4. Heart Rate and Blood Pressure Your heart pumps due to the action of the sinoatrial (or SA) node. This is a specialized tissue that controls how often your heart contracts. When this tissue fires, the rest of the myocardial tissue contracts, starting the systolic action. This node normally pulses at a rate of about 80 times a minute. Due to its role, it is sometimes called the natural pacemaker. Your nervous system can increase or decrease this rate.

5. Heart Rate and Blood Pressure Heart rate is usually determined by exercise. At rest, the average heart will beat about 70 beats per minute (bpm). Under exercise, it can commonly reach around 140 bpm. If the heart rate exceeds 160 bpm, the heart starts to not have enough time to let blood drain from the atria into the ventricles before it has to pump again. This means the ventricles don’t push as much blood as they otherwise would. This will often lead to the person being out of breath.

6. Heart Rate and Blood Pressure From here we can talk about blood pressure. Blood pressure is measured at two points. Systolic and diastolic. This gives readings for the maximum and minimum pressure the blood is exerting on the walls of vessels. This is usually measured in millimeters of mercury, a standard pressure measurement system. Categorysystolicdiastolic Hypotension< 90< 60 Desirable90–11960–79 Prehypertension120–139or 80–89 Stage 1 Hypertension140–159or 90–99 Stage 2 Hypertension160–179or 100–119 Hypertensive Crisis≥ 180or ≥ 120

7. Heart Rate and Blood Pressure Hypotension is when the blood pressure is low and blood is moving too slowly. This can result in dizziness, nausea, and fainting. If not restored, this can lead to brain damage. Categorysystolicdiastolic Hypotension< 90< 60 Desirable90–11960–79 Prehypertension120–139or 80–89 Stage 1 Hypertension140–159or 90–99 Stage 2 Hypertension160–179or 100–119 Hypertensive Crisis≥ 180or ≥ 120

8. Heart Rate and Blood Pressure The desirable range runs from a systolic pressure of 90 to 120. This range can vary from person to person though depending on their family and the amount of exercise they normally get. Categorysystolicdiastolic Hypotension< 90< 60 Desirable90–11960–79 Prehypertension120–139or 80–89 Stage 1 Hypertension140–159or 90–99 Stage 2 Hypertension160–179or 100–119 Hypertensive Crisis≥ 180or ≥ 120

9. Heart Rate and Blood Pressure If blood pressure was normal but quickly elevates to prehypertension, it could be a sign of something going wrong. Otherwise, this is usually not a problem. Blood pressure increases with age naturally, and 31% of Americans have prehypertenisve blood pressure naturally. Categorysystolicdiastolic Hypotension< 90< 60 Desirable90–11960–79 Prehypertension120–139or 80–89 Stage 1 Hypertension140–159or 90–99 Stage 2 Hypertension160–179or 100–119 Hypertensive Crisis≥ 180or ≥ 120

10. Heart Rate and Blood Pressure Hypertension is when blood pressure has reached unsafe levels. With higher pressure, the heart has to work harder to pump blood. This puts strain on the heart, lungs, and other organs. This can eventually lead to stroke, heart attack, and organ failure. Categorysystolicdiastolic Hypotension< 90< 60 Desirable90–11960–79 Prehypertension120–139or 80–89 Stage 1 Hypertension140–159or 90–99 Stage 2 Hypertension160–179or 100–119 Hypertensive Crisis≥ 180or ≥ 120

11. Heart Rate and Blood Pressure Hypertensive Crisis is when blood pressure has reached critical levels. At this stage, vessels can rupture and organs can shut down. If hypertensive crisis is not resolved immediately, it can lead to seizures, brain damage, organ failure and death. Categorysystolicdiastolic Hypotension< 90< 60 Desirable90–11960–79 Prehypertension120–139or 80–89 Stage 1 Hypertension140–159or 90–99 Stage 2 Hypertension160–179or 100–119 Hypertensive Crisis≥ 180or ≥ 120

12. Heart Rate and Blood Pressure The exact way a heart is beating can be measured by an electrocardiogram (EKG). An EKG is a device that measures electrical signals from the SA and produces a graph of voltage over time. There are 6 major intervals that can tell us many things about the condition of a person’s heart

13. Heart Rate and Blood Pressure P Wave This bump shows the voltage change between the two atria as an electrical signal travels from the SA to another node called the atrioventricular (AV) node. Abnormalities here can indicate enlarged or malformed atria.

14. Heart Rate and Blood Pressure PR Segment This gap represents the time it takes for electrical signals to go from the SA node to the AV node. Longer or shorter duration here means signals from the SA node are having problems getting to the AV node.

15. Heart Rate and Blood Pressure QRS Complex This represents the voltage change between the two ventricles. The signal pulses as the ventricles pump. This spike being too high or too low can mean thickening of ventricles, heart disease, or ventricles pumping too quickly, out of phase with everything else (tachycardia).

16. Heart Rate and Blood Pressure ST Segment This represents the period right after both ventricles have pumped. Generally, nothing is happening here, so it should be flat. Activity here can mean heart attack, or an inflammation of heart tissue. Bad!

17. Heart Rate and Blood Pressure T Wave This represents electrical depolarization going back through the ventricles (them relaxing fully). Boosts here can mean early heart attack or too much potassium in the blood, which can lead to irregular heart rhythms.

18. Heart Rate and Blood Pressure U Wave This represents the last bit of electrical signal traveling up the septum to the top of the heart. This part can be absent in most people. A large spike here means too much too much calcium, potassium, or thyroid issues.

19. Finishing Coloring Sheets At this point we’re essentially done with the circulatory system. You have the rest of class to finish all your coloring sheets for this system and to finish filling in the circulatory system page in your foldable.

20. Exit Question #29 Which systolic blood pressure below would be optimal? a) 88 b) 110 c) 132 d) 149 e) 163 f) 188