Human Heart Cheat Sheet

Key Definitions

• Heart: A muscular organ that pumps blood through the circulatory system. ✅

• Atria: Upper chambers of the heart (right and left) that receive blood. ✅

• Ventricles: Lower chambers of the heart (right and left) that pump blood out. ✅

• Valves: Structures that prevent backflow of blood (e.g., tricuspid, mitral). ✅

Important Concepts

Heart Structure

• Right Side: Pumps deoxygenated blood to the lungs via the pulmonary artery. ✅

• Left Side: Pumps oxygenated blood to the body via the aorta. ✅

Cardiac Cycle

• Systole: Contraction phase of the heart. ✅

• Diastole: Relaxation phase of the heart. ✅

Blood Flow Pathway

1. Deoxygenated blood enters the right atrium from the body.
2. Passes through the tricuspid valve to the right ventricle.
3. Pumped to the lungs via the pulmonary valve.
4. Oxygenated blood returns to the left atrium from the lungs.
5. Passes through the mitral valve to the left ventricle.
6. Pumped to the body via the aortic valve.

Key Formulas

Cardiac Output (CO) = Stroke Volume (SV) × Heart Rate (HR) ✅

• CO: Volume of blood pumped per minute.

• SV: Volume of blood pumped per heartbeat.

• HR: Number of heartbeats per minute.

Common Mistakes to Avoid

Common Mistake: Confusing the roles of the right and left sides of the heart.

Memory Tricks

Tip: "RA-LA-RV-LV" — Right Atrium, Left Atrium, Right Ventricle, Left Ventricle.

Key Diagrams

          +---------------------+
          |                     |
          |       LUNGS        |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |      LEFT ATRIUM    |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |     LEFT VENTRICLE  |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |       AORTA        |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |     BODY (TISSUES)  |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |     RIGHT ATRIUM    |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |     RIGHT VENTRICLE  |
          |                     |
          +----------+----------+
                     |
          +----------v----------+
          |                     |
          |  PULMONARY ARTERY   |
          |                     |
          +---------------------+