Overview of Heart Anatomy

Overview of the Heart Anatomy

• The heart is a muscular organ responsible for pumping blood throughout the body.
• Located in the thoracic cavity, between the lungs, tilted slightly to the left.

Heart Structure

1. Chambers:

   • Atria (2):
     • Right atrium: receives deoxygenated blood from the body via superior and inferior vena cava.
     • Left atrium: receives oxygenated blood from the lungs via pulmonary veins.
   • Ventricles (2):
     • Right ventricle: pumps deoxygenated blood to the lungs via the pulmonary artery.
     • Left ventricle: pumps oxygenated blood to the body via the aorta.

2. Valves:

   • Atrioventricular Valves:
     • Tricuspid valve: between right atrium and right ventricle.
     • Mitral valve (bicuspid): between left atrium and left ventricle.
   • Semilunar Valves:
     • Pulmonary valve: between right ventricle and pulmonary artery.
     • Aortic valve: between left ventricle and aorta.

3. Walls:

   • Epicardium: outer layer (visceral pericardium).
   • Myocardium: middle layer, composed of cardiac muscle, responsible for contractions.
   • Endocardium: inner layer lining the heart chambers.

Blood Flow Through the Heart

1. Deoxygenated blood enters the right atrium from the body.
2. Blood flows through the tricuspid valve into the right ventricle.
3. The right ventricle pumps blood through the pulmonary valve into the pulmonary artery to the lungs.
4. Oxygenated blood returns to the left atrium via pulmonary veins.
5. Blood flows through the mitral valve into the left ventricle.
6. The left ventricle pumps blood through the aortic valve into the aorta, distributing it to the body.

Electrical Conduction System

• Sinoatrial (SA) Node: primary pacemaker of the heart, initiates heartbeat.
• Atrioventricular (AV) Node: delays impulse before passing it to ventricles.
• Bundle of His and Purkinje Fibers: conduct electrical signals throughout the ventricles, causing contraction.

Coronary Circulation

• The heart receives its own blood supply through coronary arteries:
  • Right coronary artery: supplies right atrium, right ventricle, and parts of the left ventricle.
  • Left coronary artery: divides into the left anterior descending artery (LAD) and circumflex artery, supplying the left atrium and ventricle.

Function

• The heart maintains systemic and pulmonary circulation, ensuring oxygen and nutrient delivery and waste removal.

Heart Health Considerations

• Common diseases: coronary artery disease, heart failure, arrhythmias.
• Importance of lifestyle factors: diet, exercise, and regular check-ups for cardiovascular health.

Overview of the Heart Anatomy

• The heart is a muscular organ responsible for circulating blood throughout the body.
• Positioned in the thoracic cavity, it lies between the lungs and tilts slightly to the left.

Heart Structure

• Chambers:

  • Atria (2):
    • Right atrium: receives deoxygenated blood from the body via superior and inferior vena cava.
    • Left atrium: receives oxygenated blood from the lungs through pulmonary veins.
  • Ventricles (2):
    • Right ventricle: pumps deoxygenated blood to the lungs via the pulmonary artery.
    • Left ventricle: sends oxygenated blood to the body through the aorta.

• Valves:

  • Atrioventricular Valves:
    • Tricuspid valve: located between the right atrium and ventricle.
    • Mitral valve (bicuspid): positioned between the left atrium and ventricle.
  • Semilunar Valves:
    • Pulmonary valve: found between the right ventricle and pulmonary artery.
    • Aortic valve: located between the left ventricle and aorta.

• Walls:

  • Epicardium: the outermost layer, also known as visceral pericardium.
  • Myocardium: the thick middle layer made of cardiac muscle responsible for heart contractions.
  • Endocardium: the innermost lining of the heart chambers.

Blood Flow Through the Heart

• Deoxygenated blood enters the right atrium from the body.
• Blood flows through the tricuspid valve into the right ventricle.
• Right ventricle sends blood through the pulmonary valve into the pulmonary artery towards the lungs.
• Oxygenated blood returns to the left atrium via pulmonary veins.
• Blood flows through the mitral valve into the left ventricle.
• Left ventricle pumps blood through the aortic valve into the aorta for distribution to the body.

Electrical Conduction System

• Sinoatrial (SA) Node: acts as the primary pacemaker of the heart, initiating the heartbeat.
• Atrioventricular (AV) Node: delays the electrical impulse before transmitting it to the ventricles.
• Bundle of His and Purkinje Fibers: distribute electrical signals through the ventricles, prompting contraction.

Coronary Circulation

• The heart's blood supply is provided by coronary arteries:
  • Right coronary artery: supplies blood to the right atrium, right ventricle, and parts of the left ventricle.
  • Left coronary artery: bifurcates into the left anterior descending artery (LAD) and circumflex artery, serving the left atrium and ventricle.

Function

• The heart supports systemic and pulmonary circulation, facilitating oxygen and nutrient distribution while removing waste products.

Heart Health Considerations

• Common diseases include coronary artery disease, heart failure, and arrhythmias.
• Lifestyle factors such as diet, exercise, and regular check-ups play a crucial role in cardiovascular health.

This quiz covers the essential anatomy of the heart, focusing on its structure, including chambers, valves, and walls. Understand how the heart functions as a muscular organ in the thoracic cavity to pump blood throughout the body.