Section 6, Chapter 15

Aorta - Main trunk of the systemic circulation.

Divisions of the aorta
Aortic root = attachment to heart

Ascending Aorta

Aortic arch

Thoracic aorta

Abdominal aorta
Arterial Divisions

STRUCTURES AT Aortic Root
Aortic Valve

Aortic Sinus - Swelling at aortic root

Aortic Bodies
Chemoreceptors - monitor CO2 & O2 levels in blood

4. Right and left coronary arteries

Right Coronary Artery branches
Posterior interventricular artery:
supplies walls of both ventricles

Marginal artery:
supplies right atrium and right ventricle
Coronary Arteries
Left Coronary Artery branches
Anterior interventricular artery:
supplies walls of both ventricles

Circumflex Artery:
supplies left atrium and left ventricle
Blocked coronary artery = myocardial infarction

Brachiocephalic artery
Right common carotid artery: supplies right neck and head

Right subclavian artery:
supplies right arm
2. Left common carotid artery
supplies left neck and head
3. Left subclavian artery
Supplies left arm
Branches of Aortic Arch

Branches of Thoracic Aorta
Grant’s Anatomy. Branches of the thoracic aorta
Bronchial Arteries – supplies bronchi

Pericardial artery – supplies pericardium

Esophageal arteries – supplies esophagus

Branches of Abdominal Aorta
Phrenic arteries
supply diaphragm
Celiac Trunk
Gastric a. - supply stomach
Splenic a. – supply spleen & pancreas
Hepatic a. – supplies liver with O2 blood
Superior Mesenteric a.
Supplies small intestine
Suprarenal a.
Supplies adrenal glands

Branches of Abdominal Aorta
Gonadal arteries.
Male = testicular arteries
Female = Ovarian arteries
Renal arteries
Supplies kidneys
Lumbar arteries
Supplies skin and muscles of lower back
Inferior mesenteric artery
Supplies most of large intestine

Divisions of Common Carotid Arteries
External Carotid Arteries
Supplies blood to face, neck, and scalp
2. Internal Carotid Arteries
Supplies blood to brain

Provides 75% of blood to brain
Carotid Sinus - point of bifurcation
Carotid bodies – chemoreceptors
Carotid baroreceptors
Common site of stenosis (narrowing)
Arteries to the Brain, Head, and Neck

Branches of Internal Carotid Artery
1. Ophthalmic artery
supplies eyes
2. Anterior cerebral artery
supplies medial surface of brain
3. Middle cerebral artery
Supplies lateral surface of brain
Internal carotid arteries
Arteries to the Brain, Head, and Neck

Vertebral Arteries
Provides 25% of blood supply to
brain

Branch from subclavian arteries

Pass through transverse
foramen of cervical vertebrae

Enter skull through foramen
magnum
Arteries to the Brain, Head, and Neck

Basilar Artery
Both vertebral arteries merge to form a basilar
artery at the base of the brain.

Supplies blood to brainstem

Branch: Posterior cerebral artery
Supplies occipital and temporal lobes


Arteries to the Brain, Head, and Neck

Cerebral Arterial Circle (Circle of Willis)
Joins the internal carotid arteries with basilar artery at base of brain

Provides anastomoses (alternate routes) for blood flow


Arteries to the Brain, Head, and Neck

Arteries to the Shoulder and Upper Limb
Axillary Artery
Arises from subclavian artery
Brachial Artery
Continuation of axillary artery
Used for measuring blood pressure
Ulnar Artery
Continues along medial arm to wrist
Radial Artery
Continues along lateral arm to wrist

Convenient vessel for taking your pulse

Veins that drain the head and neck
Dural Venous Sinuses
Located between 2 layers of dura mater
Major CSF draining pathway from brain
Internal Jugular Veins
Drains blood from brain and
deep face
Arise from dural sinuses
External Jugular Veins
Drains blood from face, scalp, and neck

Veins that drain the arm
Ulnar & Radial Veins
drain forearm and hands
Merge for form brachial veins
Basilic Vein
Located on medial aspect of arm
Joins the brachial vein near the axilla
Cephalic Vein
Courses upward on the lateral arm
Joins axillary vein to form subclavian vein
Axillary Vein
Formed from the merging of basilic and brachial veins
Median Cubital Vein
Joins basilic and cephalic veins at elbow
Often the site of venipuncture

Hepatic Portal System
Portal System – drains blood from one capillary bed into a second capillary bed.
Hepatic Portal Vein (HPV)
Carries nutrient rich blood from abdominal viscera to the liver for processing

Hepatic Portal System
Tributaries of Hepatic Portal Vein
Gastric vein – blood from stomach

Splenic vein – blood from spleen & pancreas

Superior mesenteric vein – blood from small intestine

Inferior mesenteric vein – blood from large intestine
Abdominal Sinusoids Inferior
viscera HPV of Liver Hepatic Vein Vena Cava heart
Pathway of Hepatic Portal System
End of Chapter 15