Lecture on the Circulatory System

Overview

• Focus on vessels running to and from the heart: arteries and veins.
• Arteries: carry blood away from the heart.
• Veins: carry blood toward the heart.
• Systemic circulation color coding:
  • Red: oxygen-rich arteries.
  • Blue: oxygen-poor veins.
  • Exception: pulmonary arteries (oxygen-poor) and pulmonary veins (oxygen-rich).

Arterial Circulation

The Aorta

• Aorta: major artery leaving the heart.
  • Ascending aorta: upward part.
  • Aortic arch.
  • Descending aorta.

Coronary Arteries

• Right and Left Coronary Arteries: nourish heart cells.
• Associated arteries: circumflex artery, marginal artery, anterior interventricular artery.

Major Branches Off the Aorta

1. Brachiocephalic Trunk:
   • Divides into:
     • Right Common Carotid Artery.
     • Right Subclavian Artery.
2. Left Common Carotid Artery.
3. Left Subclavian Artery.

Carotid Arteries

• Right and Left Common Carotid Arteries: supply head and neck.
• Branch into:
  • Internal Carotid Arteries (feed brain).
  • External Carotid Arteries.

Circle of Willis

• Cerebral Arterial Circle ensures blood supply to brain despite blockages.
• Fed by:
  • Internal Carotid Arteries.
  • Vertebral Arteries.
• Components:
  • Anterior/posterior cerebral arteries.
  • Anterior/posterior communicating arteries.
  • Middle cerebral arteries.

Arteries of the Upper Limb

• From Subclavian Arteries to Axillary Arteries, Brachial Arteries, Ulnar and Radial Arteries, Palmar Arch, and Digital Arteries.

Thoracic and Abdominal Aorta

• Descending Thoracic Aorta above the diaphragm.
• Descending Abdominal Aorta below the diaphragm.
• Branches into:
  • Common Iliac Arteries, which further split into internal and external iliac arteries.

Major Arteries in the Thoracic Cavity

• Internal Thoracic Arteries.
• Anterior Intercostal Arteries.
• Posterior Intercostal Arteries.
• Superior and Inferior Epigastric Arteries.

Blood Flow to the Abdominal Organs

• Celiac Trunk:

  • Branches into Left Gastric Artery, Splenic Artery, Common Hepatic Artery.

• Superior Mesenteric Artery:

  • Feeds pancreas, small intestines, right large intestines.

• Inferior Mesenteric Artery:

  • Feeds left large intestines.

• Renal and Suprarenal Arteries feed kidneys and adrenal glands.

• Gonadal Arteries go to reproductive organs.

Arteries of the Lower Limb

• Femoral Arteries branch from external iliac arteries.
• Lead to Deep Femoral Arteries and Popliteal Arteries.
• Further divide into Posterior and Anterior Tibial Arteries.

Venous Circulation

Overview

• Veins accompany arteries but notable exceptions exist.

Major Veins

• Superior and Inferior Vena Cava bring blood back to the heart.

Drainage of the Brain

• Dural Sinuses:
  • Include superior/inferior sagittal sinuses, straight sinus, transverse sinuses, and sigmoid sinus.

Thoracic Venous System

• Hemiozygous and Azygous Veins.

Superficial Veins of Upper Limb

• Basilic, Cephalic, and Median Cubital Veins.

Hepatic Portal System

• Takes blood from digestive organs to the liver for detoxification.
• Main veins: Hepatic Portal Vein, Inferior and Superior Mesenteric Veins, Splenic Vein.

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• Summary: The lecture provided an in-depth look at the major arteries and veins of the circulatory system, focusing on arterial and venous pathways, their branches, and specific regions they supply with blood.