The heart

• Heart

  Muscular organ that pumps blood throughout the body
• Heart

  • Fist-sized organ
  • Contains four muscular sections (chambers) that briefly hold blood before moving it
  • Electrical impulses make the heart beat, moving blood through the chambers
  • Brain and nervous system direct the heart's function
• Heart

  • Works with nervous system to control heart rate
  • Works with endocrine system to control blood pressure
• The heart controls the rhythm and speed of the heart rate and maintains blood pressure
• Heart walls


  • Endocardium (inner layer), myocardium (muscular middle layer), epicardium (protective outer layer)
• Heart chambers


  • Two upper atria, two lower ventricles
• Heart valves


  • Atrioventricular valves (tricuspid, mitral), semilunar valves (aortic, pulmonary)
• Blood vessels


  • Arteries, veins, capillaries
• Coronary arteries


  • Left coronary artery, circumflex artery, left anterior descending artery, right coronary artery
• Electrical conduction system


  • Sinoatrial node, atrioventricular node, bundle branches, Purkinje fibers
• The heart is located slightly behind and to the left of the sternum, between the right and left lungs
• The average adult heart weighs about 10 ounces and is about the size of a fist
• Common heart conditions


  • Arrhythmia, cardiomyopathy, congestive heart failure, coronary artery disease, diabetes, heart attack, heart valve disease, high blood pressure, high cholesterol, pericarditis
• Common symptoms of heart conditions

  Chest pain, heart palpitations, dizziness, shortness of breath, fatigue, swelling
• Common tests to check heart health

  • Blood pressure measurement, electrocardiogram, echocardiogram, chest X-ray, blood tests, cardiac catheterization, CT scan, heart MRI, stress test
• Common treatments for heart conditions

  • Medications, lifestyle changes, medical devices, procedures, operations
• How to keep the heart healthy

  Achieve and maintain a healthy weight, moderate alcohol intake, eat heart-healthy foods, be physically active, limit sodium, manage stress, quit smoking