872 cardio pulm review

Cardiac output

The volume of blood ejected out of the left ventricle into the systemic vasculature per minute

Stroke volume

The volume ejected from the left ventricle per beat

Autonomic innervation and catecholamine hormones

Two main factors that influence HR

Branch from the CV control center located in the medulla to the heart

Location of autonomic neurons

End diastolic volume

Cardiac contractility

Afterload

Three main factors that regulate stroke volume

EDV

The amount of blood in the ventricle at the end of diastole (filling phase)

Cardiac contractility

The force by which the heart contracts

Afterload

The opposing pressure that the left ventricle has to overcome in order to eject blood into the aorta

Preload

Measurement of the amount of pressure/stretch placed on the walls of the ventricle

Frank-starling mechanism

If more blood fills the ventricle during diastole then there will be a greater stretch on the cardiac muscle cells

This increase in stretch causes the heart to contract with more force

The pressure in the left ventricle must be greater than the pressure in the aorta (Afterload)

In order for blood to flow out of the left ventricle into the aorta

Ejection fraction

The volume of blood ejected from the ventricles relative to the volume of blood that entered the ventricles during diastole

End systolic volume ESV

The volume of blood that remains in the ventricles after contraction

Systolic BP

The pressure that the blood exerts on the walls of the blood vessel when the heart contracts

Diastolic BP

Represents the pressure that the blood exerts on the walls of the blood vessel when the heart is relaxed

Cardiac output and total vascular resistance

Two main factors that influence BP

The diameter of the lumen of a blood vessel

Factor that influences vascular resistance

Done by the kidneys via the regulation of blood volume

The long term regulation of BP

Done by cardiac baroreceptors

Short term regulation of BP

Cardiac baroreceptors

Pressure receptors that are located in the walls of the aortic arch and the carotid sinus

Mediastinum

Central component of the thorax between the two pleural cavities

• heart

• Trachea

• Esophagus

• Great vessels

• Lymph nodes

• Nerves

• Fat

Contents of the mediastinum

Parietal pericardium

Fibrous outer layer of the pericardium

Visceral pericardium or epicardium

Inner layer of the pericardium and forms the outer layer of the heart

Epicardium

Thin outer layer with adipose tissue and blood vessels that supply the heart and is the inner layer of the pericardium

Myocardium

Thick middle layer composed of cardiac muscle that facilitates the pumping action of the heart

Mechanical cells and conductive cells

Two categories of myocardial cells

Endocardium

Internal layer of simple squamous epithelium

Right AV valve (tricuspid)

Blood gets sent from the right atrium to the right ventricle via the

Bicuspid/mitral valve

Blood gets sent from the left atrium to the left ventricle via the

Left coronary artery

Supplies left atrium, left ventricle, and interventricular septum

Circumflex artery

Reaches posterior surface of the heart by traveling the AV groove around the L side

Left anterior descending

Supplies the left ventricle and is called the widowmaker

Right coronary artery

Supplies the right atrium, right ventricle, AV and SA nodes

Coronary sinus

Wide vein that runs transversely across the posterior surface of the heart in the coronary groove

Collects deoxygenated blood from the cardiac muscles and empties into the right atrium