Cardiac Cycle Presentation Notes

Introduction

• Focus: Presentation on the cardiac cycle.
• Key Terms: Cardiac cycle, Diastole, Systole.

Overview of Cardiac Cycle

• Definition: Events related to blood flow from one heartbeat to the next.
• Phases:
  • Diastole: Blood fills the ventricles.
  • Systole: Blood is pumped out into arteries.

Diastolic and Systolic Events

Diastole

• Cardiac Diastole: Heart relaxes after contraction and refills with blood.
• Ventricular Diastole: Ventricles relax.
• Atrial Diastole: Atria relax.
• Process:
  • Pressure drops in the ventricle.
  • Mitral valve opens as pressure falls below left atrium.
  • Phases:
    • Rapid filling
    • Reduced filling
    • Atrial systole

Systole

• Cardiac Systole: Ventricles contract to pump blood.
• Phases:
  • Rapid ejection
  • Reduced ejection
  • Protodiastole

Heart Sounds

• Normal Sounds:
  • S1: Closure of AV valves, beginning of ventricular contraction.
  • S2: Closure of semilunar valves, end of ventricular systole.
  • Components:
    • A2: Aortic component
    • P2: Pulmonary component
  • Physiological Split: During inspiration, A2 precedes P2.

Murmurs

• Definition: Extra or unusual sounds due to turbulent blood flow.
• Types:
  • Innocent Murmurs: Not caused by heart problems.
  • Abnormal Murmurs: Caused by heart defects or valve disease.

Characteristics

• Timing:
  • Systolic
  • Diastolic
  • Continuous

Systolic Murmurs

• Types:
  • Ejection type: Caused by aortic valve stenosis.
  • Configuration: Crescendo-decrescendo.
  • Severity: Affects shape and relationship between A2 and P2.

Diastolic Murmurs

• Types:
  • Early, Mid, Late, or Prolonged
  • Causes: Regurgitation or stenosis of valves.

Continuous Murmurs

• Example: Patent ductus arteriosus (abnormal aorta-pulmonary artery connection).
• Description: Machinery murmur.

Identification and Examination

• Location: Where murmur is best heard; 5 auscultation sites.
• Radiation: Direction sound radiates, usually aligns with blood flow.
• Diagnostic Measures: Echocardiogram and other tests.

Conclusion

• Understanding of heart sounds and murmurs essential for accurate diagnosis and management.
• Importance of subsequent examinations for suspected abnormal murmurs.