Cardiac Output, Blood Flow, and Blood Pressure

These flashcards encapsulate key concepts related to cardiac output, blood flow, blood pressure, and their regulation mechanisms as discussed in your lecture.

Cardiac Output

The volume of blood pumped each minute by each ventricle; calculated as stroke volume multiplied by heart rate.

Stroke Volume

The amount of blood pumped by the heart with each beat, typically averaging 70-80 ml/beat.

Heart Rate

The number of times the heart beats per minute, with an average of 70 bpm.

Frank-Starling Law

The principle stating that stroke volume is proportional to end-diastolic volume (EDV), indicating that the heart pumps out more blood with more volume loaded.

Ejection Fraction

The percentage of end-diastolic volume that is ejected during ventricular contraction.

Autonomic Regulation of Heart Rate

Regulation of heart rate through the autonomic nervous system, modifying heart rate via sympathetic and parasympathetic activity.

Baroreceptor Reflex

A reflex mechanism that helps regulate blood pressure via stretch receptors that respond to changes in the arterial wall tension.

Vascular Resistance

Resistance controlled by small arteries and arterioles, affecting blood pressure and flow.

Total Peripheral Resistance

The overall resistance to blood flow within the systemic circulation, influencing blood pressure.

Atrial Natriuretic Peptide (ANP)

A hormone released by the heart that reduces blood pressure by promoting fluid loss and inhibiting ADH release.

Venous Return

The amount of blood that returns to the heart from the venous circulation, crucial for determining end-diastolic volume.

ADH (Antidiuretic Hormone)

A hormone that promotes water reabsorption in the kidneys, thereby increasing blood volume.

Aldosterone

A hormone released in response to low blood volume/pressure, which helps in sodium retention and indirectly increases water retention.

Sympathetic Innervation

The part of the autonomic nervous system that increases heart rate and myocardial contractility.

Parasympathetic Innervation

The part of the autonomic nervous system that decreases heart rate and myocardial contractility.

Systolic Pressure

Aortic pressure during ventricular systole, the highest pressure in the arteries.

Diastolic Pressure

Aortic pressure during ventricular diastole, the lowest pressure in the arteries.

Korotkoff Sounds

The sounds heard through a stethoscope during blood pressure measurement, indicative of blood flow through an artery.

Pulse Pressure

The difference between systolic and diastolic pressure, reflecting the strength of the pressure wave.

Mean Arterial Pressure (MAP)

An average arterial pressure during a single cardiac cycle, important for driving blood flow to organs.