The Cardiovascular System Lecture Notes

Flashcards covering cardiovascular system anatomy, physiology, cardiac conduction, systemic and pulmonary pathways, blood pressure, and related pathologies based on lecture notes.

What is the primary function of the cardiovascular system?

To deliver oxygen and nutrients and to remove carbon dioxide and other waste products.

Where is the heart located in the body and where is its apex directed?

The heart is located in the thorax between the lungs, with its pointed apex directed toward the left hip.

What are the three layers that make up the heart wall?

1. Epicardium (outside layer, parietal pericardium, connective tissue)
2. Myocardium (middle layer, mostly cardiac muscle)
3. Endocardium (inner layer, endothelium)

Which heart chambers are classified as receiving chambers, and which are discharging chambers?

 The right and left atria are receiving chambers, while the right and left ventricles are discharging chambers.

What structures anchor the atrioventricular valves to prevent backflow during ventricular contraction?

Chordae tendineae (commonly called "heart strings").

What is the functional difference between an incompetent valve and a stenotic valve?

An incompetent valve allows backflow and forces the heart to repump blood, while a stenotic (stiff) valve increases the heart's workload.

Which great vessels exit the right ventricle and the left ventricle, respectively?

The pulmonary arteries leave the right ventricle, and the aorta leaves the left ventricle.

Where does blood from the coronary circulation empty back into the heart?

It empties into the right atrium via the coronary sinus.

What is the complete sequence of blood flow through the heart, starting from the venae cavae?

Superior and inferior vena cava $\rightarrow$ right atrium $\rightarrow$ tricuspid valve $\rightarrow$ right ventricle $\rightarrow$ pulmonary semilunar valve $\rightarrow$ pulmonary trunk and arteries to the lungs $\rightarrow$ pulmonary veins leaving the lungs $\rightarrow$ left atrium $\rightarrow$ bicuspid valve $\rightarrow$ left ventricle $\rightarrow$ aortic semilunar valve $\rightarrow$ aorta to the body.

Which node in the heart's intrinsic conduction system serves as the pacemaker?

The sinoatrial (SA) node, located in the right atrium.

What electrical events correspond to the P wave, QRS complex, and T wave on an electrocardiogram (ECG)?

The P wave represents atrial depolarization, the QRS complex represents ventricular depolarization, and the T wave represents repolarization of the ventricles.

How are tachycardia and bradycardia defined in terms of heart rate?

Tachycardia is a rapid heart rate of more than $100\text{ beats/min}$, whereas bradycardia is a slow heart rate of less than $60\text{ beats/min}$.

What formula is used to calculate Cardiac Output (CO)?

$\text{CO} = \text{HR} \times \text{SV}$ (Cardiac Output = Heart Rate $\times$ Stroke Volume).

What is Starling's law of the heart?

It states that the more the cardiac muscle is stretched, the stronger the resulting contraction will be.

What clinical conditions result from left-sided failure versus right-sided failure in Congestive Heart Failure (CHF)?

Left-sided failure leads to pulmonary congestion and suffocation, while right-sided failure leads to peripheral congestion and edema.

How do structural differences distinguish arteries from veins?

Arteries have thicker walls with a thicker tunica media, smaller lumens, and no valves. Veins have thinner walls with a thicker tunica externa, larger lumens, and valves.

What three factors assist in the movement of venous blood back to the heart?

1. Skeletal muscle contraction ("milking" action)
2. Presence of valves in veins
3. Respiratory movements (pressure changes in thorax and abdomen)

What two types of vessels form capillary beds, and what are their roles?

Vascular shunts directly connect an arteriole to a venule, while true capillaries function as exchange vessels for nutrients and wastes.

What are the standard normal numerical ranges for human systolic and diastolic blood pressure?

Normal systolic pressure ranges from $110\text{--}140\text{ mm Hg}$ and normal diastolic pressure ranges from $75\text{--}80\text{ mm Hg}$.

What drug is used in Congestive Heart Failure to produce a slow, steady, and stronger heartbeat?

Digitalis.

How does tissue plasminogen activator (t-PA) work to dissolve blood clots?

t-PA converts plasminogen into plasmin, which is an enzyme that dissolves blood clots.

At what developmental points in the embryo does the heart start pumping and become a four-chambered organ?

The simple "tube heart" pumps by the fourth week, and it becomes a four-chambered organ by the end of seven weeks.

What are the adult remnants of the fetal foramen ovale and ductus arteriosus?

The remnant of the foramen ovale is the fossa ovale, and the remnant of the ductus arteriosus is the ligamentum arteriosum.