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Major Blood Vessels Overview

Jun 15, 2025

Overview

This lecture covers the major arteries and veins of the human body, describing their pathways, branches, and functions in blood circulation.

Arterial System: Major Arteries

  • The pulmonary arteries carry blood from the heart to the lungs.
  • The aorta is the largest artery and can be divided into the ascending aorta, aortic arch, and descending aorta.
  • Major branches of the aorta include coronary arteries, brachiocephalic, left common carotid, and left subclavian arteries.
  • The descending aorta gives rise to the thoracic and abdominal aorta.
  • The abdominal aorta branches into right and left renal arteries (to kidneys) and right and left common iliac arteries.

Arterial System: Major Branches to Regions

  • The brachiocephalic artery branches into the right subclavian and the right common carotid arteries.
  • The common carotid arteries diverge into external and internal carotid arteries.
  • Subclavian arteries become axillary (chest wall), then brachial (upper arm), then ulnar (ulna side) and radial (radius side) arteries.
  • The radial artery at the wrist is used for taking the radial pulse.
  • Abdominal aorta splits into right and left common iliac arteries, each dividing into internal (pelvis) and external (main lower limb supply) iliac arteries.
  • External iliac artery becomes femoral (thigh), then popliteal (knee), and then anterior and posterior tibial arteries (lower leg).

Venous System: Pathways and Major Veins

  • Veins return blood to the heart and often parallel arteries with similar names.
  • Pulmonary veins carry blood from the lungs to the heart.
  • Superior vena cava and inferior vena cava drain into the right atrium.

Venous System: Veins by Region

  • External jugular veins (R & L) drain face, scalp, superficial neck; internal jugular veins (R & L) drain brain and deep face/neck.
  • Jugular veins drain into subclavian veins, then brachiocephalic veins, forming the superior vena cava.
  • Arm veins (radial, ulnar, brachial, axillary, subclavian, brachiocephalic) mostly parallel their respective arteries.
  • Renal veins (kidneys) and hepatic veins (liver) drain into the inferior vena cava.
  • Leg veins (anterior/posterior tibial, popliteal, femoral, external/internal/common iliac) follow arterial counterparts.
  • The great saphenous vein is the body's longest vein, running up the medial leg and joining the femoral vein.

Key Terms & Definitions

  • Aorta — The largest artery in the body, carrying blood from the heart to systemic circulation.
  • Common Carotid Artery — Major artery supplying blood to the head and neck.
  • Subclavian Artery — Supplies blood to the arms, becoming axillary and then brachial arteries.
  • Radial Pulse — Pulse felt at the wrist, over the radial artery.
  • Vena Cava — Large veins (superior and inferior) returning blood to the right atrium.
  • Jugular Vein — Veins draining blood from the head and neck.
  • Great Saphenous Vein — The longest vein, running the length of the lower limb.

Action Items / Next Steps

  • Review diagrams of the arterial and venous systems to reinforce anatomical pathways.
  • Memorize the main branches and regions supplied by major arteries and veins.
  • Practice labeling arteries and veins on blank diagrams as study prep.