Cardiovascular System and Electrophysiology

A collection of vocabulary flashcards to assist in the review of key concepts related to the cardiovascular system and its electrophysiological properties.

Chambers of the heart

The four main sections of the heart: right atrium, right ventricle, left atrium, left ventricle.

Atria purpose

Low-pressure primer pumps that receive venous return and top off ventricles.

Ventricles function

Generate pressure to eject blood into the pulmonary and systemic circuits.

Right heart function

Receives deoxygenated blood and sends it to the lungs for gas exchange.

Left heart function

Receives oxygenated blood and sends it to systemic tissues at high pressure.

Calcium-induced calcium release (CICR)

Mechanism where L-type Ca²⁺ influx triggers a massive release of Ca²⁺ from the sarcoplasmic reticulum.

Pacemaker cell action potential

Characterized by a diastolic (pre-) potential due to If (funny) Na⁺ current and T-type Ca²⁺.

Bradycardia

Heart rate less than 60 bpm.

Tachycardia

Heart rate greater than 100 bpm.

Atrial fibrillation (AF)

Chaotic atrial activity leading to decreased atrial kick.

Ejection fraction

The percentage of blood pumped out of the ventricles with each heartbeat; typically 50-65% at rest.

Stroke volume (SV)

Volume of blood ejected by the ventricle with each contraction; calculated as EDV - ESV.

Cardiac output (CO)

Volume of blood the heart pumps per minute; calculated as HR × SV.

Preload

The degree of stretch of the myocytes at the end of diastole; related to EDV.

Afterload

The arterial pressure the ventricle must overcome to eject blood.

Respiratory exchange

The process of oxygen and carbon dioxide exchange in the lungs.

Heart Rate (HR) regulation

Modulated by sympathetic (increases HR) and parasympathetic (decreases HR) nervous systems.