Lecture Notes Human Anatomy & Physiology

Human anatomy and physiology
Lecture 1 – Anatomy of the heart
- What is the anatomical position of the heart in the thorax?  sternal angle, 5th intercostal
space: parasternal on the right, midclavicular on the left
- What is the mediastinum?  space within the rib cage between the lung cavities
- What is the structure of the heart?

Sternal angle: base of heart
Intercostal: between ribs
Parasternal: next to the sternum
Midclavicular: mid of “sleutelbeen”

Mediastinum:

- Superior mediastinum  above the heart
1. Thymus  lymphoid tissue, regression
2. Nerves
Vagal nerves: regulation of internal organ functions
Left recurrent laryngeal nerve: control intrinsic muscles of the larynx (except cricothyroid
muscle)
Phrenic nerves: causes hiccups, enters the diaphragm (major muscle of respiration,
located below the lungs)
Sympathetic trunk: component of the autonomic nervous system
3. Thoracic duct  lymphatic drainage
4. Vessels  aa. and vv. thoracicae internae (internal thoracic arteries)
- Inferior mediastinum  contains the heart
1. Anterior  space between the sternum and the heart
2. Middle  the heart
3. Posterior  descending aorta, esophagus, vessels, thoracic duct, nerves (vagal nerves,
sympathetic trunk)

Pericardial cavity: balloon in which everything moves smoothly, fluid causes cardiac tamponade

- Visceral pleura  membrane that covers each lung
- Parietal  membrane that is attached to the thoracic (or other body) cavity
Transverse sinus(/cavity): transition from visceral to parietal
Oblique sinus:
Coronary sinus: collects blood from the heart (independent circulation)
Interventricular sulcus: 2 grooves (anterior and posterior) that separates the
ventricles of the heart
 When parietal cavity is punctured  fills with blood; heart cannot expand

Trunk + anatomical context  it will split at some point
E.g., pulmonary trunk: 2 pulmonary arteries

Right atrium (posterior):

- Right auricula (pectinate muscles)
- Vena cava (inferior + superior)
- Coronary sinus

, - Interatrial septum (oval fossa)
- Crista terminalis  ridge between the smooth and rough wall

Right ventricle (anterior):

- Tricuspid valve  septal, anterior, posterior cusps; chordae tendinae, papillary muscles
- Pulmonary valve (semilunar)
- Pulmonary trunk

Left atrium:

- Left auricle
- Pulmonary veins
- Interatrial septum

Left ventricle:

- Thicker wall  greater circulation to entire body
- Ascending aorta
- Aortic valve (semilunar)
- Left atrioventricular valve (mitral, bicuspid)

What do valves need to function?  firm connective tissue around the valves, arteries

Diastole  relaxation of the heart after contraction
Systole  contraction of the ventricles to pump blood
 Heart receives blood during relaxation (diastole)

Conduction system:

- SA node  gives off rhythm without brain interference (own rhythm)
- AV node  stops the signal and gives off signal after x milliseconds (own rhythm)
- Bundle of His  bundle branches
- Purkinje fibers

4 heart valves:

- Tricuspid valve  between the right atrium and the right ventricle
- Pulmonary valve  between the right ventricle and the pulmonary artery
- Mitral valve  between the left atrium and the left ventricle
- Aortic valve  between the left ventricle and the aorta

, Lecture 2 – Embryology of the heart
Heart formation:

1. Forming straight heart tube  lateral heart tubes form together to form one tube
- Venous pole  blood comes in, up)
- Arterial pole  blood comes out, down (dorsal aorta)
2. Forming primitive heart
- Looping  atrium migrates to cranial (up)
- Rotation  right atrium and ventricle rotate to ventral
 Pericardium development:
1. Primordial heart tube in pericardial sac
2. Primordial transverse pericardial sinus
3. Heart loops ventrally
4. Primordial arterial and venous poles  form transverse pericardial sinus
5. Veins expansion + pericardial reflection  form oblique pericardial sinus
3. Forming fetal heart
1. Septation atria  septum/foramen 1primum and secundum  foramen ovale
2. Septation ventricles
4. Post-natal changes

Situs inversus  malformation in which the apex is on the right (dextrocardia)

Ventricular septum defect  last step; therefore the most common defect

Tetralogy of Fallot (4 things happening):

1. Pulmonary stenosis (narrowing)
2. VSD (ventricular septum defect)  right ventricle has to work harder to pump blood into
narrow pulmonary artery
3. Blood gets pumped into the aorta  overriding aorta
4. Enlarged right ventricle