THE CIRCULATORY SYSTEM Medical Therapeutics

Bell Work What is the job of the Circulatory System in the body? What other body systems does it work with? What does pulmonary mean? What does Cardiac mean? What body cavity is the heart located in?

Standard 11) Outline the gross normal structure and function of all body systems and summarize appropriate medical text(s) in order to relate signs and symptoms of common diseases and disorders with each. Cardiovascular System

Objective By the end of class, student will be able to Understand main functions of the heart Identify the 4 chambers of the heart and the 4 heart valves Interpret the meaning of heart sounds and blood pressure

Key Terms Pulmonary – means anything dealing with the lungs Cardiac – means anything dealing with the heart Heart: a muscular organ that pumps blood to the lungs and the body.

Physiology Also known as Cardiovascular System Carries blood around the body It is composed of the heart, lungs, and blood vessels Works with respiratory system to oxygenate blood to the body

CARDIOLOGY A PERSON’S HEART WILL BEAT APPROXIMATELY 100,000 TIMES A DAY, EVERY DAY IMAGINE TRYING TO SQUEEZE A TENNIS BALL 70 TIMES A MINUTE…..THAT IS WHAT YOUR HEART DOES EVERYDAY Why do you think your heart rate increases during exercise?????

Apex of Heart Lowest tip of the organ that points downward at the base, forming what almost looks like a rounded point. Strongest beat can be heard and even felt here!!! Stethoscope – instrument used to hear the heartbeat

The Heart Size of a closed fist Weighs 12-13 oz Location – thoracic cavity, pericardial cavity within the mediastinum

Structure Hollow, muscular, double pump that circulates blood At rest = 2 oz blood with each beat, 5 qts./min., 75 gallons per hour Ave = 72 beats per minute 100,000 beats per day PERICARDIUM – double layer of fibrous tissue that surrounds the heart MYOCARDIUM – cardiac muscle tissue, forms 4 chambers ENDOCARDIUM – smooth inner lining of heart SEPTUM – partition (wall) that separates right half from left half

CORONARY ARTERIES Supply the myocardium with oxygenated blood Blockage OR Infarction of one of these arteries. Causes a Myocardial Infarction (MI) Left main artery – called “widow maker” because it pumps blood to rest of artery

Structure 1. Aorta – takes blood away from left ventricle to rest of the body 2. Superior vena cava and 3. inferior vena cava – bring deoxygenated blood to right atrium Pulmonary artery (6) – takes blood away from right ventricle to the lungs for O2 Pulmonary veins (7) – bring oxygenated blood from lungs to left atrium

Chambers and Valves SEPTUM (11) divides into R and L halves Upper chambers – RIGHT ATRIUM (4) and LEFT ATRIUM (5) Lower chambers – RIGHT VENTRICLE (8) and LEFT VENTRICLE (9) Four heart valves permit flow of blood in one direction

VALVES Tricuspid – 3 flaps or cusps – prevents backflow into R atrium Pulmonary (12)– 3 flaps – prevents backflow into R ventricle Mitral (bicuspid) (10) – 2 flaps – prevents backflow into L atrium Aortic – prevents backflow into L ventricle

RIGHT SIDE OF THE HEART DEOXYGENATED BLOOD SUPERIOR VENA CAVA INFERIOR VENA CAVA RIGHT ATRIUM TRICUSPID VALVE RIGHT VENTRICLE PULMONARY SEMILUNAR VALVE PULMONARY ARTERIES RIGHT AND LEFT LUNGS

LEFT SIDE OF THE HEART OXYGENATED BLOOD PULMONARY VEINS LEFT ATRIUM BICUSPID (MITRAL) VALVE Left VENTRICLE AORTIC SEMILUNAR VALVE AORTA

PHYSIOLOGY OF THE HEART The heart is a double pump PHYSIOLOGY OF THE HEART The heart is a double pump. When the heart beats… Right Heart Deoxygenated blood flows into heart from vena cava  right atrium  tricuspid valve  right ventricle  pulmonary semilunar valve  pulmonary artery  lungs (for oxygen) Left Heart Oxygenated blood flows from lungs via pulmonary veins  left atrium  mitral valve  left ventricle  aortic semilunar valve  aorta  general circulation (to deliver oxygen)

CARDIAC CYCLE Creates Heart sounds Heard through stethoscope “LUB-DUB” sound 1st sound – longest and loudest (closure of AV valves) 2nd sound – closure of aortic and pulmonary valves If valves do not close properly – you will hear an extra sound called a heart murmur

Heart Rate Measured in beats per minute Normal Heart Rate Adults – 60-100 Abnormal Heart Rates <60 BPM – Bradycardia >100 BPM – Tachycardia Your heart rate is: 70 BPM (70 beats per minute)

Heart Rate State if normal, bradycardia, tachycardia 176 BPM 44 BPM

THE CARDIAC CYCLE SYSTOLE – CARDIAC CONTRACTION THE BLOOD IS FORCED OUT OF THE HEART TO THE LUNGS FOR OXYGENATION AND TO THE BODY FOR CIRCULATION (CONTRACTION) DIASTOLE – CARDIAC RELAXATION THE BLOOD IS RETURNED TO THE HEART FROM THE LUNGS AND THE BODY (RELAXATION)

Blood Pressure Measured in mmHg (milimeters of mercury) Normal Blood Pressure Range 120-140/60-90 Systolic – pressure when your heart beats (top number) Diastolic – pressure when your heart relaxes between beats (bottom number)

Blood Pressure High blood pressure Low blood pressure >140/90 mmHg Hypertension Low blood pressure <90/60 mmHg Hypotension

Blood Pressure Blood pressure readings: State if normal, hypertensive or hypotensive 165/98 mmHg 78/44 mmHg 128/76 mmHg 220/126 mmHg 132/88 mmHg

Objective By the end of class, student will be able to Understand main functions of the heart Identify the 4 chambers of the heart and the 4 heart valves Interpret the meaning of heart sounds and blood pressure