91 terms



Terms in this set (...)

What's another name for muscle cell?
Muscle fiber
What about the cardiac muscle makes the characteristic wave of contraction (depolarization) that leads to a wringing out of the heart ventricles.
The cardiac muscle the fibers that branch and connect/bind to each other.
The first part of the heart to contract is?
The atria
What is a specialized feature of the cardiac muscle?
Intercalated Discs. Specialized cell junctions you see in cardiac that allows electrical current / depolarization to go through the cardiac muscle.
What is the Sarcolema
The cell membrane of cardiac tissue/cell.
How many chambers does the heart have?
Two Atria - (Superior)
Two Ventricle (Inferior)
What are the name of the two circuits the heart uses to pump blood?
What circuit is used to pump blood into the right side of the heart?
The pulmonary circuit
What circuit is used to pump blood into the general circulation of the body?
The systemic circuit
What side of the body is usually associated with heart failure?
The left. The left side of the heart is no longer efficient as a pump.
What is connected to the atria?
The pulmonary veins.
Signs and Sx of left sided pump failure.
Cold limbs, hair loss, necrosis of the limbs.
Signs/Sx of not enough blood going to the carotid arteries?
Syncope, fatigue and weakness
What happens if the right heart is not effective in pumping out blood?
Hypoxia, Increase jugular vein pressure.
Describe blood flow through the heart.
R. Atrium -> R. Ventricle -> Pulmonary trunk, -> Pulmonary arteries (No Oxygen in Pulm. Art. -> Pulm Capillaries -> Organs for gas exchange -> Pulmonary Veins (have Oxygen) -> Left Atrium->Left Ventricle -> Aorta (largest artery of body) -> General Circulation-> Systemic circulation through capillary bed.
Where is the heart located?
Left of the midline just left of the medial steinum.
Where is the R ventricle
The anterior surface of the heart
Why would the heart be bigger than normal?
Hypertension. When there is increased systemic pressure, the heart has to pump harder to overcome the increased pressure..

Which leads to...
Hypertrophy (a muscle that gets bigger). By making more Actin and Myosin, the protein.

The apical point of index then has to move over to the left.
What is the beginning part of the aorta called?
Ascending aorta, then Aortic Arch
Name the first branches off the ascending aorta just distal to the valve?
Coronary arteries
What do the coronary arteries do?
Oxygenate the heart. The most oxygenated blood coming from the aorta comes goes to the coronary arteries.
When do the coronary arteries get fed?
During diastilly. When the aortic valve closes and there is back flow. The back flow then goes into the coronary arteries.
Where does the Pulmonary trunk come off of?
The right ventricle
What does the pulmonary trunk bifurcate into?
R and L pulmonary arteries. (low oxygen content)
What is an Artery?
A vessel that brings blood AWAY from the heart.
Where does the oxygenated blood come from?
Pulmonary veins (Coming back from the lungs)
Where does the oxygenated blood go to?
Left Atrium
What is the outside casing of the heart called?
The Pericardium
What is the pericardium?
The serous (double layer with potential space and a small amount of fluid) membrane lining the pericardial cavity.
What are the two forms of layers making up the pericardial membrane?
- Visceral pericardium (also called the epicardium)
- Parietal pericardium
What layer of the pericardium is closest to the organ/heart?
The Visceral Layer
What layer of the pericardium is closest to the wall of the body?
The Parietal pericardium
What is the fibrous pericardium?
The the part of the Parietal pericardium that attaches to diaphragm.
Name the 3 layers of the heart wall.
- Epicardium: External surface
-Myocardium: Consists of cardiac muscle cell
-Endocardium: Internal surface (also the VALVES of the heart)
What is the endocardium?
The inner layer of the heart and the VALVES of the heart.
How many heart valves?
Two semi lunars Valves
Aorta valve
AV Valve
Where are the Semi Lunar valves?
At the junction of the pulmonary trunk and right ventricle.
Where is the Aorta Valve?
Between the left ventricle and the Aorta.
Where is the Mitral Valve / bicuspid valve? (An AV valve)
Between the left atrium and the right atrium. It's an Atrial Ventricular valve
Tricuspid Valve (An AV valve)
Between the right atrium and right ventricle.
What do the valves do?
They open and close during the cardiac cycle.
- The semi lunar valves are like the front door.
-The AV Vales are like the back door.
What happens if the mitral valve does not close all the way?
Blood regurgitates back into the Left Atrium.
What are the Characteristics of Cardiac Muscle Cells?
- Dependent on aerobic respiration (oxygen from the coronary arteries)
- Cardiocytes contract without information coming from the CNS
-Cardiocytes are interconnected by intercalated discs.
Where does the Cardiocytes (heart cells)get its information to contract?
The cardiac conduction system
Where is most input to the heart come from.
- The sympathetic system.
- But the CNS does have some control too.
The histological functioning unit. The area between the Z lines. Inside the Sarcolemmae is micro-fillaments, Actin and myosin
How many anchoring parts does the pericardium have
The pericardium has two anchoring points
How can the the four chambers of the heart be identified?
By sulci on the external surface
Name the four sulci.
-Interatrial sulcus: separates the left and right atria.
-Coronary Sulcus: Separates the atria and the ventricles.
-Anterior interventricular Sulcus: Separates the left and right ventricles.
-Posterior interventricular sulcus: also separates the left and right ventricles.
What is the Ligamentum arteriosum?
The fetus gets its oxygen from its mother. It connects the pulmonary trunk to the aorta. A way to bypass the lungs.
Where does the heart get its nutirents/oxygen?
The coronary arteries.
What is the superior vena cava?
The main vein that brings blood back to the right atrium.
What does the inferior vena cava do.
Brings blood back to the heart from the body.
How are the left and right atria oriented?
- Positioned superior to the coronary sulcus
- Both have thin walls
- Both consist of expandable extensions called auricles
How are the left and right ventricles oriented?
- Positioned inferior to the coronary sulcus
- Much of the right ventricle forms the diaphragmatic surface
Where does the secondary heart sound come from?
The ascending aorta
What is the Superior vena cave?
The main vein that brings blood back to the right atrium from the head and neck.
What is the Inferior vena cava
Brings blood back to the right atrium from the body.
Where does the right atrium receive blood from?
Superior/inferior Vena cava and the Coronary sinus.
What is the Coronary sinus?
The venus section of the coronary system. Brings blood into the right atrium.
Where does blood come from in the right ventricle?
Deoxygenated blood comes from the right atrium.
- Blood enters the ventricle by passing through the tricuspid valve.
What does chordae tendineae do?
Connects to three papilary muscles to prevent inversion when the VENTRICLES contract.
What is papillary muscle?
It connects to the chordea tendineae which holds the valves. (prevent inversion upon contraction)
What does the right ventricle consist of?
Trabeculae carneae
- A meaty meshwork (not solid)

Moderator band

Pulmonary valve
- Leads to the pulmonary trunk, then to the right and left pulmonary arteries
Where does the Ascending aorta begin?
The semi lunar valve.
Left Atrium Anatomy
- Receives oxygenated blood from the lungs via the right and left pulmonary veins

- Does not have pectinate muscles

- Blood passes through the bicuspid valve
Why does the left ventricle have a thicker wall?
Because the left ventricle works against the resistance of the "entire" systemic arterial blood pressure.
What is after-load?
The load that the heart has to pump against.
What is preload?
The amount of blood going to the heart.
What is the Left Ventricles after-load?
systemic arterial pressure
What does the Right Ventricle pump against (after load)?
Pulmonary pressure - not a lot of pressure.
Structure of the Heart Valves
- Ring of connective tissue that connects to the heart tissue
- Cusps
- Chordae tendineae
- Papillary muscles
What is the function of heart valves?
To ensure correct flow of blood into the heart and outside the heart.
Where is the Tricuspid Valve (Atrialventricular Valve)
The right atria and right ventricle
What doe the Coronary Blood Vessels do?
Supply blood to the heart muscles.
Where do the coronary arteries begin?
They branch off the ascending aorta near its base.
Name the three coronary vessels.
- Right coronary artery (RCA)
- Left coronary artery (LCA)
- Cardiac veins
Where does the coronary sinus dump its blood?
Right atrium
What are the Major branches off the right coronary artery.
-Atrial branches
-Right marginal branch
-Posterior interventricular branch
-Conducting system branches
The new word for LAD
Anterior Interventricular Artery
What are the major branches off the left coronary arteries?
Circumflex branch
Anterior interventricular branch
What is anastomoses?
When two vessels join. In the heart, anastomoses is normal.
Name the cardiac veins.
- Posterior vein of the left ventricle
- Middle cardiac vein
- Small cardiac vein
- Anterior cardiac veins

All the above drain into the great cardiac vein

Great cardiac vein drains into the coronary sinus

All the above eventually lead to the right atrium
What is the cardiac cycle?
The cardiac cycle consists of alternate periods of contraction and relaxation.
What part of the cardiac cycle is contraction?
- Blood is ejected into the ventricles
- Blood is ejected into the pulmonary trunk and the ascending aorta
What part of the cardiac cycle is relaxation?
- Chambers are filling with blood
Are the AV valves open in diastole?
Where does the cardiac conduction system begin?
At the SA Node (pace maker). Which is in the sinus of the right atrium.
What is the autonomic nervous system?
Visceral efferent (Exit)
The motor system going to the viscera.
What regulates the heart
Autonomic Nervous System
Autonomic Nervous System
- Sympathetic nervous system (SNS) stimulation is activated by stress, anxiety, excitement, or exercise

- Parasympathetic nervous system (PNS) stimulation is mediated by acetylcholine and opposes the SNS
- PNS dominates the autonomic stimulation, slowing heart rate and causing vagal tone