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The Heart 2 muscular pumps in one: - left heart pumps blood to the body tissues - right heart pumps blood to the lungs The heart circulates the blood through the circulatory system. Blood carries oxygen and nutrients to cells. Anatomy of the Heart. Consists of 4 chambers
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The Heart • 2 muscular pumps in one: - left heart pumps blood to the body tissues - right heart pumps blood to the lungs The heart circulates the blood through the circulatory system. Blood carries oxygen and nutrients to cells
Anatomy of the Heart • Consists of 4 chambers - 2 atria – superior chambers, thin walls - 2 ventricles – inferior chambers, thicker walls • Valves - Tricuspid – separates right atrium and right ventricle - Bicuspid – separates left atrium and left ventricle Valves direct the flow of blood and prevents any backflow Heart murmur – if a valve is damaged or does not close properly, blood leaks backwards, causing a “noise”
The Path of Blood in the Heart • Enter Right Atrium from superior and inferior vena cava (largest veins in body) • Right atrium to the right ventricle through tricuspid valve • Right ventricle through pulmonary semilunar valve into pulmonary arteries • Pulmonary arteries to lungs (gets oxygen) • Exit lungs via pulmonary veins • Pulmonary veins into left atrium • Left atrium into left ventricle through bicuspid valve • Left ventricle into aorta through semilunar valve Aorta is the largest artery in the body
Blood is forced out of the ventricles with each heartbeat – walls of the left ventricle are thicker • Cardiac Output – volume of blood pumped by left ventricle per minute (5 L) • Stroke volume – volume of blood pumped by each ventricle per minute
Death on the Soccer Field • Antonio Puerta, a midfielder for Sevilla FC, collapsed during a game on August 25, 2007. • He regained consciousness and was walked to the locker room where he collapsed again. • He was resuscitated and brought to the ICU of a nearby hospital. • He suffered multiple prolonged cardiac arrests over the next several hours resulting in anoxic brain injury and multisystem organ failure. • He died 3 days after his initial collapse at age 22. • Work-up revealed arrhythmogenic right ventricular cardiomyopathy (ARVC). Antonio Puerta (November 26, 1984 – August 28, 2007) http://soccernet.espn.go.com/news/story?id=457723&cc=5901
The Physiological Adaptations in the Trained Athlete • Athletic training for competitive endurance (aerobic) or isometric (static or power) sports results in characteristic changes in cardiac structure and function. • This physiological form of left ventricular (LV) hypertrophy is known as the “athlete’s heart” and must be distinguished from pathological conditions that may predispose to SCD. • Depending on the nature of the exercise training benign increases in LV mass, wall thickness, and cavity size as well as left atrial volume may be observed in healthy athletes. N Engl J Med 2003;349:11
The Physiological Adaptations in the Trained Athlete Endurance Training Isometric Training • Increase in LV cavity size • Minimal increase in LV wall thickness • Increase in LV wall thickness out of proportion to increase in cavity size Circulation 2000;101:336
Extrinsic Risk Factors for SCD • The risk of SCD in competitive sports increases with “burst” exertion (rapid acceleration and deceleration; common in basketball, tennis, and soccer). • Extreme environmental conditions (temperature, humidity, and altitude) that affect blood volume and electrolyte balance also contribute to the risk. • Progressive and systematic training to achieve higher levels of conditioning and performance may further increase the risk by resulting in a total cardiovascular demand that often exceeds that of competition. Circulation 2004;109:2807 J Am Coll Cardiol 2005;45:1364
Other Extrinsic Risk Factors for SCD • Cocaine abuse • Amphetamine abuse • Performance enhancing drugs (anabolic steroids) • Dietary and nutritional supplements (including ephedra-containing products) N Engl J Med 2001;345:351 J Am Coll Cardiol 2002;39:1083
An inherited, degenerative disorder of the connective tissue • It affects the eyes, heart and blood vessels, and the bones and joints • More than 50,000 Americans affected • Signs and Symptoms: • Dislocated lenses of the eye • Aortic aneurysm • Above average height • Signs – unusually tall, near sighted (glasses), arm span exceeds height, flexible or limber, flat feet, possible scoliosis
Treatment: • Cannot be cured • Annual echocardiograms • Eye exams • Avoidance of strenuous activities such as weight lifting, high impact aerobics, and scuba diving • Avoid contact sports such as boxing, football, rugby
Commotio Cordis • June 6, 2006 – 12 year old Steven Domalewski was hit by a line drive in the chest – vegetative state (Wayne, NJ) • December, 2010 – 16 year old Thomas Adams from Garfield, NJ died when struck in the chest by a baseball in Paterson, NJ • http://www.northjersey.com/sports/145_million_settlement_reached_in_Louisville_slugger_case.html
Commotio Cordis • A condition that results from a blow to the chest wall at a specific point between heartbeatsthat disrupts the electrical activity of the heart • The heart stops beating and instead shakes and quivers • Only about 230 people have died from it since records began in 1998 • Once it happens, the only treatment is defibrillation, but work less than 20% of the time
Protection from Commotio Cordis • Metal/Composite bats vs. wooden bats • Chest guards
Websites • http://www.kbtx.com/news/features/9/1112742.html • http://stjosephaspirin.com/