Heart and Neck Vessels (Neck vessles)

Pulse

  • The pulse is a pressure wave generated by each systole, pumping blood into the aorta.
  • The carotid artery is a central artery, close to the heart, and its timing closely coincides with ventricular systole.
  • Location:
    • In the groove between the trachea and the sternomastoid muscle.
    • Medial to and alongside that muscle.
  • Waveform characteristics:
    • Smooth, rapid upstroke.
    • Rounded and smooth summit.
    • More gradual downstroke with a dicrotic notch caused by the closure of the aortic valve.

Jugular Venous Pulse and Pressure

  • Jugular veins empty deoxygenated blood directly into the superior vena cava.
  • There's no cardiac valve separating the superior vena cava from the right atrium.
  • Jugular veins provide information about the right side of the heart's activity, reflecting fluid pressure and volume changes.
  • Increased volume and pressure occur when the right side of the heart fails to pump effectively, leading to jugular vein distention.
  • Two jugular veins on each side of the neck:
    • Internal jugular:
      • Lies deep and medial to the sternomastoid muscle.
      • Usually not visible, but diffuse pulsations may be seen in the sternal notch when supine.
    • External jugular:
      • More superficial.
      • Lies lateral to the sternomastoid muscle above the clavicle.

Arterial vs. Jugular Pulse

  • Arterial pulse: Caused by forward propulsion of blood.
  • Jugular venous pulse: Results from a backwash, a waveform moving backward due to upstream events.

Five Components of the Jugular Venous Pulse

  • Occur due to events on the right side of the heart.

    • A wave:
      • Reflects atrial contraction.
      • Some blood flows backward to the vena cava during right atrial contraction.
    • C wave:
      • Ventricular contraction.
      • Backflow from the bulging upward of the tricuspid valve at the beginning of ventricular systole.
      • Not from the neighboring carotid artery pulsation.
    • X descent:
      • Atrial relaxation.
      • The right ventricle contracts during systole, pulling the bottom of the atria downward.
    • V wave:
      • Passive atrial filling.
      • Increase in volume in the right atria and increased pressure.
    • Y descent:
      • Passive ventricular filling.
      • The tricuspid valve opens, and blood flows from the right atrium (RA) to the right ventricle (RV).