Understanding Heart Sounds

Overview of Heart Sounds

• The lecture explains the causes of heart sounds and how they change with heart conditions.
• Two main concepts: Cardiac Cycle and Blood Flow are essential to understanding heart sounds.

The Cardiac Cycle

• Phases:
  • Systole: contraction phase
  • Diastole: relaxation phase
• More details on the cardiac cycle are available in a series linked in the lecture.

Blood Flow Basics

• Blood enters the atria from the body and is pumped out by the ventricles.
• Right side: Blood goes to the lungs.
• Left side: Blood goes to the body.

Heart Sounds Explained

• S1 (Lub): Occurs when the atrioventricular valves (tricuspid and mitral) close at the start of systole.
• S2 (Dub): Occurs when aortic and pulmonary/pulmonic valves close at the beginning of diastole.

Additional Heart Sounds

• S3:

  • Common in children and young adults.
  • Occurs right after S2 during early diastole as blood rushes into the ventricles.
  • Known as the "ventricular gallop."
  • Sometimes described with the word "Kentucky" for timing.
  • In adults, it can indicate potential heart problems.

• S4:

  • Known as the "atrial gallop."
  • Occurs late in diastole, just before S1.
  • Caused by blood being pushed into a stiff ventricle.
  • Timing described with the word "Tennessee."
  • Indicates possible cardiac issues.

Heart Murmurs

• Abnormal sounds occurring between S1 and S2.
• Can indicate valve problems (leaky or narrowed valves) causing turbulent blood flow.
• Types of Murmurs:
  • Systolic Murmurs: Occur during systole (heart contraction).
  • Diastolic Murmurs: Occur during diastole (heart relaxation).

Listening to Murmurs

• Systolic Murmur: Swishing sound with S1.
• Diastolic Murmur: Swishing sound with S2.
• Combined Murmurs indicate more severe valve problems.

Conclusion

• Abnormal heart sounds should be evaluated by healthcare professionals.
• Recommended to watch the related video on the cardiac cycle for a deeper understanding.

Additional Resources

• Free cardiac cycle guide available in the video description.
• Further exploration in a series on the cardiac cycle.