Clinical Med: Cardio

• The right ventricle pumps blood to the lungs, while the left ventricle pumps oxygenated blood throughout the body.
• Pericardium is the outermost layer of the heart and acts as a protective covering
• Myocardium is the middle layer and is the muscular layers that facilitates pumping
• Endocardium is the innermost layer of the heart and lines the chambers of the heart, continuous with heart valves
• IV drug use is the biggest cause of endocarditis
• Aorta delivers oxygenated blood from the left ventricle to the body
• Pulmonary artery delivers deoxygenated blood from the right ventricle to the lungs
• Pulmonary veins delivers oxygenated blood from the lungs to the left atrium
• Superior and inferior vena cavas deliver deoxygenated blood from the body to the right atrium
• the left coronary artery splits into the left anterior descending and the circumflex arteries
• The left anterior descending (LAD) supplies 70% of the left ventricle aka widow maker
• Circumflex artery supplies lateral left ventricle
• Right coronary artery supplies the SA node, AV node, right ventricle, and posterior left ventricle
• an occlusion in a coronary artery causes an infarct in the heart
• the right ventricle has to do with electrical conduction
• the left ventricle is responsible for pumping blood out of the heart
• Bicuspid valve separates the left atrium from the left ventricle
• Tricuspid valve separates the right atrium from the right ventricle
• The mitral valve prevents backflow into the left atrium during systole
• The tricuspid valve prevents backflow into the right atrium during systole
• Atrioventricular valves

  • Bicuspid aka mitral valve is on the left side
  • Tricuspid valve is on the right side
• Semilunar valves

  • aortic
  • pulmonic
• Mitral and aortic valves fail the most
• Papillary muscles connect to the valves via the chordae tendinae

  • contract to prevent prolapse/inversion of the valves
• Chordae tendinae serve to anchor the bicuspid and tricuspid valves

  • attach to valves and papillary muscles
• Trabeculae carneae are irregular muscle ridges in the ventricular wall
• Automaticity is the ability to initiate its own electrical impulse
• Excitability is ability to respond to electrical stimulus
• Conductivity is the ability to transmit electrical impulses from cell to cell
• Contractility is the ability to stretch as a single unit, then passively recoil while actively contracting
• Rhythmicity is the ability to repeat the cycle in synchrony with regularity
• Path of blood through the body

  • left atrium
  • blood goes through the bicuspid AV valve
  • Left ventricle
  • through aortic semilunar valve
  • Aorta
  • Body tissues
  • Vena cava
  • Right atrium
  • blood through the tricuspid AV valve
  • Right ventricle
  • blood through the pulmonary semilunar valve
  • Pulmonary arteries
  • Lungs
  • Pulmonary veins
• Systole is the heart contracting
• Diastole is the heart relaxing
• Early diastole is when blood flows from the vena cavas into the right atrium and from the pulmonary veins into the left atrium
• In early diastole the bicuspid and tricuspid valves open and blood passively flows from the atria to the ventricles
• 70% of blood passively flows from the atria to the ventricles
• Late diastole is when the ventricles are relaxed and the atria are contracting

  • the remaining 30% of blood is pushed to the ventricles by atrial kick
  • Tricuspid/mitral valves are closed
• Early systole is when the ventricles begin to contract and the valves are closed, isovolumetric contraction
• in early systole the valves will open and blood goes to the aorta and pulmonary arteries