Heart Murmurs and Valve Disorders

Introduction to Heart Murmurs

• Heart murmurs are sounds created by turbulent blood flow within the heart.
• Detected using a stethoscope and can indicate anything from normal findings to significant abnormalities.
• Normal heart sounds are from valve closures:
  • S1: Mitral and Tricuspid valves (start of systole)
  • S2: Aortic and Pulmonary valves (start of diastole)
• Turbulent blood flow produces audible sound waves.

Types of Murmurs

• Physiological Murmurs: Expected in certain situations, such as in hyperdynamic states like anemia.
• Pathological Murmurs: Due to structural heart changes.

Describing Murmurs: Mnemonic 'SCRIPT'

• S - Site: Location where the murmur is best heard.

  • Aortic Stenosis: Best heard at the aortic area (Right sternal border, second intercostal space).
  • Pulmonic Area: Left sternal border, second intercostal space.
  • Erb's Point: Left sternal border, third intercostal space.
  • Tricuspid Area: Fourth intercostal space, left sternal edge.
  • Mitral Area: Fifth intercostal space, midclavicular line.

• C - Character: Nature of the sound.

  • Aortic Stenosis: Crescendo-decrescendo sound (diamond-shaped on phonogram).

• R - Radiation: Other areas where the murmur is heard.

  • Aortic Stenosis: Radiates to carotid arteries.

• I - Intensity: Loudness of the murmur (Grades 1-6).

  • Non-pathological murmurs usually less than grade 3.

• P - Pitch: Frequency of the murmur.

  • Aortic Stenosis: High-pitched.

• T - Timing: When in the cardiac cycle the murmur is heard.

  • Aortic Stenosis: Systolic murmur (between S1 and S2).

Valve Disorders and Associated Murmurs

Aortic Stenosis

• Narrow pulse pressure.
• Maneuvers: Squatting increases murmur intensity.
• Right-sided murmurs louder with inspiration (mnemonic: 'RYLE').

Aortic Regurgitation

• Blood flows back into left ventricle during early diastole.
• Best heard: 2nd-4th intercostal spaces on left side.
• Character: Blowing, decrescendo.
• Clinical signs:
  • de Musset's sign: Head nodding with heartbeat.
  • Corrigan's sign: Visible carotid artery distension/collapse.
  • Water hammer pulse.
• Maneuvers: Squatting increases sound.

Mitral Stenosis

• Narrowing of mitral valve.
• Best heard at the apex.
• Character: Rumbling, mid-diastolic with opening snap.
• Signs: Malar flush, irregular pulse.
• Maneuvers: Valsalva release, squatting increase murmur.

Mitral Regurgitation

• Blood flows back into left atrium during systole.
• Best heard at the apex.
• Character: Blowing, high-pitched pan-systolic murmur.
• Radiation to the axilla.
• Maneuvers: Squatting increases intensity.
• Mitral Valve Prolapse: Mid-systolic click.

Pulmonary Stenosis

• Affects pulmonary valve.
• Best heard at pulmonary area.
• Crescendo-decrescendo systolic murmur.
• Split S2 sound.

Pulmonary Regurgitation

• Insufficiency of pulmonic valve.
• Best heard at pulmonic area.
• Early diastolic, high-pitched decrescendo.

Tricuspid Stenosis

• Rare, often caused by rheumatic fever.
• Best heard at tricuspid area.
• Character: Scratching, rumbling with soft opening snap.
• Signs: Raised JVP, liver discomfort.

Tricuspid Regurgitation

• Blood leaks back into right atrium.
• High-pitched pan-systolic murmur at tricuspid area.
• Possible epigastric audibility.
• Epstein's anomaly association.
• Louder with inspiration (Cavallo's sign).