The Circulatory System

How will knowing this help me to be a better Chiropractor? 1) Understanding cardiac anatomy will help me perform a better physical exam. 2) It will allow me to explain cardiac and circulatory dysfunctions to my patients. 3) It will help me in future course work.

Introduction –Functions of the circulatory system Transportation –RBC’s carry O2 and CO2 –nutrients –waste products –hormones Protection –WBC’s, immune cells, antibodies

Major components of the circulatory system Blood Blood vessels Heart

The Heart

Location and General Description –apex is between 5th and 6th ICS –Mediastinum - median portion of the thoracic cavity, contains all thoracic viscera except the lungs. –Pericardium fibrous pericardium serous pericardium –parietal serous pericardium –visceral serous pericardium - epicardium pericardial cavity

Heart wall –epicardium –myocardium –endocardium

Heart Chambers and Valves –4 chambers, 2 upper atria and 2 lower ventricles –interatrial septum –interventricular septum –atrial walls and much thinner than ventricular walls –atrioventricular valves - right and left –semilunar valves - aortic and pulmonary

circulation of blood through the heart Blood from the body returns to the right atrium via the Vena Cavae, then past the right AV valve to the right ventricle. Then past the semilunar valve into the pulmonary trunk to the lungs, blood returns in the pulmonary veins to the left atrium, past the left AV valve to the left ventricle, past the semilunar valve in to the aorta - to be delivered to body

Right Atrium Vessels entering the right atrium –superior Venn cava –inferior Venn cava –coronary sinus Pectinate muscles Fossa ovale

Right Ventricle –Right atrioventricular valve - tricuspid valve –Chordae tendineae –Papillary muscles –Trabeculae carneae –Conus arteriosus –Pulmonary valve - pulmonary semilunar valve –Pulmonary trunk

Left Atrium –Pulmonary veins - 4 Left Ventricle –Left atrioventricular valve - bicuspid valve, mitral valve –Aortic valve - aortic semilunar valve –Aorta

Conduction System of the Heart Sinoatrial node - SA node - internodal fibers - carry impulses down to the ventricles Atrioventricular node - AV node Atrioventricular Bundle - Bundle of His Conduction Myofibers - Purkinje Fibers

Systole - contraction of the heart, especially the ventricles Diastole - postsystolic dilation of the heart, in which the chambers fill with blood

Heart sounds first heart sound - Lub - closing of the AV valves, during ventricular systole second heart sound - dup - closing of the semilunar valves, during ventricular diastole

The Coronary Vessels

Right Coronary Artery –Right marginal artery –Posterior Interventricular artery Left Coronary Artery –Anterior Interventricular artery –Circumflex artery Coronary Veins –Great cardiac vein –Middle cardiac vein –Coronary sinus

The Blood Vessels

BP = CO x PR Peripheral resistance –blood vessel length obesity –viscosity of blood water consumption and renal output –vessel diameter effects of drugs CO = HR x SV –factors that affect heart rate –factors that affect stroke volume

Blood Pressure 120/ = systolic pressure –pressure generated by the contraction of the left ventricle –things that affect systolic pressure 80 = diastolic pressure –pressure present in the arterial system –due to pressure placed on blood by arterial walls

The Arteries Aortic Arch –Brachiocephalic Trunk Right common carotid artery Right subclavian –Left common carotid artery –Left subclavian

Blood Supply to the Neck and Head Common carotid artery –Internal carotid artery ophthalmic artery posterior communicating artery anterior cerebral artery middle cerebral artery

Common Carotid artery, cont. External carotid artery –superior thyroid a. –ascending pharyngeal a. –lingual a. –facial a. –maxillary a. –superficial temporal a. –posterior auricular a. –occipital a.

Arteries to the Shoulder and Upper Extremity

Subclavian artery Vertebral artery –basilar artery –Circle of Willis posterior cerebral artery posterior communicating artery internal carotid artery

Thyrocervical trunk thyroid gland, trachea and larynx –inferior thyroid a. –suprascapular a. –transverse cervical a.

Costocervical trunk upper intercostal m., Spinal cord, meninges, posterior neck muscles. –superior intercostal a. –deep cervical a. Internal thoracic a.

Axillary artery (inferior to first rib) superior thoracic a. thoracoacromial a. –acromial a. –deltoid a. –pectoral a. –clavicular a. lateral thoracic a. subscapular a. –circumflex scapular a. –thoracodorsal a. anterior and posterior circumflex humeral aa.

Brachial artery (inferior to the teres major m.) –profunda a. –superior ulnar collateral a. –inferior ulnar collateral a. Radial artery –joins ulnar to form the superficial palmar arch Ulnar artery –superficial palmar arch

Branches of the Thoracic Portion of the Aorta –pericardial arteries –bronchial arteries –esophageal arteries –posterior intercostal arteries –superior phrenic arteries

Branches of the Abdominal Portion of the Aorta Inferior phrenic a. Celiac Trunk (for foregut derivatives) –left gastric a. –common hepatic a. –splenic a. Superior mesenteric a.(for midgut derivatives) –inferior pancreaticoduodenal a. –jejunal and ileal aa. –Ileocolic a. –right colic a. –middle colic a.

Branches of the Abdominal Aorta, con’t. Inferior mesenteric a. (for hind gut derivatives) –left colic a. –sigmoid a. –superior rectal a. Renal arteries –suprarenal a. Gonadal arteries –testicular a. - male –ovarian a. - female Lumbar arteries Middle sacral a.

Arteries of the Pelvis and Lower Extremity Common iliac arteries –External iliac a. femoral a. –superficial circumflex iliac a. –superficial epigastric a. –superficial external pudendal a. –deep external pudendal a. –profunda femoris a. - medial and lateral femoral circumflex aa. –Popliteal a. –Anterior Tibial a. - dorsal pedal a and arcuate a. –Posterior Tibial a. - peroneal a. and medial and lateral plantar aa. –Internal iliac a. internal pudendal a. and perineal a.

The Veins Veins that Drain the Brain –Dural Sinuses superior sagittal sinus inferior sagittal sinus straight sinus confluence of sinuses transverse sinus sigmoid sinus internal jugular vein

Veins, cont. Miscellaneous Veins –Medial cubital vein –Great saphenous vein

Portal systems Hepatic portal vein –superior mesenteric vein –splenic vein –liver drained by the hepatic vein Hypophyseal portal system –superior hypophyseal a. –primary plexus –long and short hypophyseal portal veins - to adenohypophysis –secondary plexus –efferent hypophyseal veins to cavernous sinus

Fetal circulation

The End of Systemic Anatomy Lecture Material