Cardiovascular System: Anatomy, Conduction, Blood Vessels, and Blood Pressure

Comprehensive vocabulary flashcards covering the cardiovascular system, heart anatomy, circulation circuits, cardiac conduction, electrocardiogram waves, vascular structures, and blood pressure categories.

Path of Blood Through the Heart

The sequential pathway of blood flow: Vena Cava (Superior/Inferior) $\rightarrow$ Right Atrium $\rightarrow$ Tricuspid Valve $\rightarrow$ Right Ventricle $\rightarrow$ Pulmonary Valve $\rightarrow$ Pulmonary Artery $\rightarrow$ Lungs $\rightarrow$ Pulmonary Veins $\rightarrow$ Left Atrium $\rightarrow$ Mitral (Bicuspid) Valve $\rightarrow$ Left Ventricle $\rightarrow$ Aortic Valve $\rightarrow$ Aorta $\rightarrow$ Body.

Pulmonary Circuit

The circuit that re-oxygenates the blood and releases carbon dioxide waste; the right ventricle pumps deoxygenated blood through the pulmonary arteries into the lungs (where blood drops off $CO_2$ and picks up $O_2$), and oxygenated blood returns to the left atrium via pulmonary veins.

Systemic Circuit

The circuit that delivers oxygen and nutrients to tissues and collects waste; the left ventricle pumps oxygenated blood through the aorta to the upper and lower body (where blood drops off $O_2$ and picks up $CO_2$), and deoxygenated blood returns to the right atrium via the vena cavae.

Systole

The phase of the cardiac cycle where the heart muscle actively contracts and squeezes blood out of its chambers.

Diastole

The phase of the cardiac cycle where the heart muscle relaxes, allowing the chambers to open up and passively fill with incoming blood.

Lubb

The lower-pitched, longer heart sound caused by the closure of the atrioventricular (AV) valves (the tricuspid and mitral valves), which prevents blood from flowing backward into the atria.

Dupp

The sharper, higher-pitched, shorter heart sound caused by the closure of the semilunar valves (the aortic and pulmonary valves) at the beginning of ventricular diastole, preventing blood from rushing backward into the ventricles from the arteries.

Sinoatrial (SA) Node

Specialized nodal tissue located in the upper wall of the right atrium near the superior vena cava that initiates each electrical impulse of the heart.

Internodal Tracts / Atrial Pathways

Specialized muscle fibers in the right atrium that carry the electrical impulse from the SA node across the atrial myocardium.

Atrioventricular (AV) Node

Nodal structure located in the lower part of the interatrial septum that temporarily delays the electrical signal to allow the atria to fully empty blood into the ventricles.

Bundle of His (Atrioventricular Bundle)

The bridge of specialized fibers that receives the impulse from the AV node and carries it from the atria down into the interventricular septum.

Right and Left Bundle Branches

The split paths of the bundle of His that travel down either side of the interventricular septum toward the apex of the heart.

Electrocardiogram (ECG)

A diagnostic recording that measures the electrical activity passing through the heart muscle over time.

P Wave

The portion of an ECG representing atrial depolarization, in which the electrical signal spreads from the SA node across both atria, causing atrial muscle cells to contract.

QRS Complex

The portion of an ECG representing ventricular depolarization; the signal travels through Purkinje fibers and sweeps across the ventricles as a steep, rapid spike, triggering a strong ventricular contraction.

T Wave

The portion of an ECG representing ventricular repolarization, during which ventricular muscle cells reset their electrical charges to a resting state to relax and prepare for the next impulse.

Arteries

Strong, most elastic blood vessels that transport blood away from the heart under high pressure.

Arterioles

Smaller, branched tubes that stem from arteries and lead toward capillaries.

Capillaries

Blood vessels with the smallest diameter and thin walls where blood moves the slowest and which wrap around organs.

Venules

Small blood vessels that branch off from capillaries and lead into veins.

Veins

Vessels that bring blood back to the heart and possess thinner walls than arteries.

Vasoconstriction

A sympathetic nervous system response that reduces blood vessel diameter, leading to increased blood pressure.

Vasodilation

A sympathetic nervous system response that increases blood vessel diameter, leading to decreased blood pressure.

Aorta

The major artery that originates from the heart, travels down the center of the body, and becomes the abdominal aorta.

Carotid Artery

A major artery that supplies blood to the neck and head.

Brachial Artery

A major artery that travels down the arm.

Femoral Artery

A major artery that travels down the leg.

Blood Pressure

The force blood exerts against the inner walls of arteries, typically represented as systolic pressure over diastolic pressure.

Systolic Pressure

The top number in a blood pressure measurement, which reflects the pressure in the arteries when the heart beats or contracts.

Diastolic Pressure

The bottom number in a blood pressure measurement, which reflects the pressure in the arteries when the heart rests between beats.

Normal Blood Pressure

A blood pressure measurement defined as less than $120 / 80\,\text{mm Hg}$.

Elevated Blood Pressure

A blood pressure category defined by a systolic reading between $120\text{–}129\,\text{mm Hg}$ and a diastolic reading of less than $80\,\text{mm Hg}$.

Stage 1 Hypertension

A blood pressure classification defined by a systolic reading of $130\text{–}139\,\text{mm Hg}$ or a diastolic reading of $80\text{–}89\,\text{mm Hg}$.

Stage 2 Hypertension

A blood pressure classification defined by a systolic reading of $140\,\text{mm Hg}$ or higher or a diastolic reading of $90\,\text{mm Hg}$ or higher.

Hypertensive Crisis

A severe cardiovascular state defined by a systolic reading over $180\,\text{mm Hg}$ and/or a diastolic reading over $120\,\text{mm Hg}$.

Cardiac Output

The total volume of blood pumped by each ventricle of the heart over a given period, typically measured in liters per minute ($\text{L/min}$).