Circulatory System Notes Part II

Heart structure of other organisms Single circulation Heart is 2-chambered Blood pressure is low after blood passes through gill capillaries Swimming helps propel blood to systemic capillaries and back to the heart #10

Heart structure of other organisms Double circulation Heart is 3-chambered Gas exchange occurs at the lungs and skin Blood from two atria mix into a single ventricle, a ridge diverts the oxygen-poor from the oxygen rich blood #10

Heart structure of other organisms Double circulation Heart is 3-chambered Ventricle is partially divided, less mixing of the blood occurs #10

Heart structure of other organisms Double circulation Heart is 4-chambered Helps support high metabolic rates of birds and mammals; pumps enough fuel and oxygen to body tissues Left ventricle has thicker walls than right ventricle #10

Blood Pressure Blood pressure: the force that blood exerts against the walls of your blood vessels Measured in the arteries of the arm at the same height of the heart. 120 / 70  healthy young adult blood pressure numerator = systolic pressure donominator = diastolic pressure #11

Blood Pressure

Cardiac Cycle Systole: – “Lub” – Contraction phase – Atriums contract to completely fill the ventricles – Then, ventricles contract to pump blood into the arteries – Tricuspid and Mitral valve are closed – Pulmonary and Aortic valves are open #12

Cardiac Cycle Diastole: – “Dub” – Relaxed phase – Blood flows into all 4 chambers – Tricuspid and Mitral valves are open – Pulmonary and Aortic valves are closed #12

Pump it up! Average amount of blood pumped out of heart per beat (cardiac cycle) = 70mL Average number of heart beats (cardiac cycles) per minute = 72 How much blood does the heart pump per minute? 70mL x 72 heart beats = 5040 mL/min (5L/min) A drop of blood can travel through the entire systemic circuit in one minute! #13

SA Node Each heart muscle contracts and relaxes to an intrinsic rhythm…how? SA Node: (sinoatrial node) is a group of cells that set the rate at which all the cardiac muscle cells contract, it is your pacemaker. Found in the upper wall of the right atrium. Generates electrical impulses similar to a nerve cell. These electrical impulses in the heart generate electrical changes in the skin, which can be detected and recorded by an electrocardiogram (EKG). #14

Artificial Pacemakers Artificial Pacemaker: a device that emits electrical signals to trigger normal heart beats #14

Heart Attack ½ the deaths in the US are caused by cardiovascular disease 1/3 rd of heart attack victims die immediately #15 DescriptionWarning Signs (Symptoms)Treatments or Preventions -When one or more coronary arteries become blocked, heart muscles die -SA Node unable to maintain a normal rhythm -Chest discomfort -Discomfort in other parts of the body (arms, neck, jaw, stomach) -Shortness of breath - Cold sweat -Electrical shocks from an external defibrillator (AED) - Aspirin -Exercise and healthy diet

Stroke #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions - Death of brain tissue due to lack of O2 - Blockage of arteries in the head - Face Drooping - Arm Weakness - Speech Difficulty - Time to call Blood thinning medications - Rehabilitation

Deep Vein Thrombosis #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions A blood clot that forms in a vein deep in the body Most occur in the lower leg or thigh A loose clot can travel to the lung’s arteries and block flow (pulmonary embolism) Swelling of the leg Pain or tenderness in the leg when standing or walking Anticoagulants Vena Cava Filter Compression Stockings

Myocarditis #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions Inflammation of the heart muscle caused by a viral or bacterial infection Stabbing chest pain Shortness of breath during exercise Small amounts of urine Antibiotics Diuretics (promotes production of urine) Calcium channel blockers (increases supply of blood and O 2 to the heart)

Murmur #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions Most murmurs are harmless. A heart murmur is an extra or unusual sound heard during a heartbeat. Leaky valves A bluish color on the skin, especially on the fingertips and lips Enlarged neck veins Excessive sweating with minimal or no exertion Sometimes the symptoms go away by themselves Lifestyle changes

Aneryusm #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions Balloon-like bulge in an artery Can rupture (burst) and cause internal bleeding  fatal Damage and weakening of the artery’s walls Build up of plaque Avoid smoking Surgical removal Insertion of a stent

Reynaud’s Disease #15 Description Signs of Disease (Symptoms) Treatments or Preventions Difficultly of carrying blood to extended parts of the body (hands and feet) Brief episodes of vasospasm, which is a narrowing of the blood vessels. Cold temperatures or stress can trigger “attacks” Skin may turn white and then blue for a short time As blood flow returns, the affected areas may turn red and throb, tingle, burn, or feel numb Protection from cold temperatures Learn ways to handle stress

Hypertension #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions High blood pressure “Silent Killer” Blood Pressure above: 120/80 No other symptoms are usually seen the beginning years of the condition Eat less than teaspoon of salt a day (1,500mg) Weight loss Exercise Healthy diet Avoid stress pressure/ss/slideshow-hypertension-overview

Polycythemia Vera #15 DescriptionSigns of Disease (Symptoms) Treatments or Preventions body makes too many red blood cells Thickens blood making it difficult for oxygen-rich blood to flow to parts of the body Feelings of pressure or fullness on the left side of the abdomen due to an enlarged spleen Heavy bleeding from small cuts A pint of blood is removed once a week until RBC count is normal.

Warafin Anticoagulant – prevents clotting of the blood Higher risk of bleeding because of the thinner blood #16

Aspirin Taking an aspirin as soon as symptoms start greatly improves the chance of survival. Aspirin is an anti-inflammatory drug. Aspirin “thins” the blood and helps prevent blood clots from forming. #16

Angioplasty A procedure to open narrow/blocked coronary arteries. A deflated balloon catheter inserted into a coronary artery. The balloon is inflated, compressing the plaque against the artery wall. #16

Stents A small mesh tube that's used to treat narrow or weak arteries. Helps support the inner wall of the artery #16

Bypass Surgery A healthy blood vessel taken from the leg, arm, chest or abdomen and connects it to the other arteries in the heart. Blood is bypassed around the diseased or blocked area #16

Heart Transplant A heart transplant replaces the patient's heart with a donor heart. #16