The Heart Lecture Presentation

These flashcards cover key concepts related to the anatomy and physiology of the heart, cardiovascular system functions, electrical conduction, and clinical relevance.

Cardiovascular system

System that includes the heart, blood, and blood vessels.

Heart rate

The number of beats per minute of the heart.

Stroke volume

The amount of blood pumped by the left ventricle in one contraction.

Cardiac output

The volume of blood the heart pumps per minute; calculated as heart rate multiplied by stroke volume.

Atrioventricular (AV) valves

Valves located between the atria and ventricles, including the tricuspid and mitral valves.

Semilunar valves

Valves located between the ventricles and arteries, including the aortic and pulmonary valves.

Fossa ovalis

An oval-shaped scar on the interatrial septum of the heart, a remnant of the foramen ovale.

Foramen ovale

An opening in the fetal heart that allows blood to bypass the lungs.

Pericardium

The fibrous sac that encloses the heart.

Myocardium

The muscular layer of the heart responsible for contraction.

Endocardium

The innermost layer of the heart lining the chambers and valves.

Coronary arteries

Blood vessels that supply blood to the heart muscle.

Capillaries

Small blood vessels where exchange of substances occurs.

Pacemaker cells

Cells in the heart that initiate and regulate the heartbeat.

Sinoatrial (SA) node

The primary pacemaker of the heart located in the right atrium.

Atrioventricular (AV) node

A cluster of cells that serves as an electrical relay station between the atria and ventricles.

Electrical conduction system

A network of pacemaker and conducting cells that coordinate heart contractions.

Cardiac cycle

The sequence of events in one heartbeat involving contraction (systole) and relaxation (diastole).

Atrial contraction

Phase when the atria push blood into the ventricles.

Ventricular contraction

Phase when the ventricles eject blood into the arteries.

Cardiac tamponade

Restriction of heart function due to fluid accumulation in the pericardial cavity.

Coronary circulation

The flow of blood to and from the tissues of the heart.

Coronary artery disease (CAD)

A condition characterized by the narrowing of coronary arteries due to plaque.

Myocardial infarction (MI)

A heart attack caused by insufficient blood flow to the heart muscle.

Angina pectoris

Chest pain due to reduced blood flow to the heart muscle.

Ejection fraction

The percentage of end-diastolic volume that is ejected from the heart during contraction.

Preload

The degree of stretch of the heart muscle prior to contraction.

Afterload

The pressure against which the heart must work to eject blood.

Frank–Starling principle

The relationship between preload and stroke volume.

Bradycardia

Abnormally slow heart rate.

Tachycardia

Abnormally fast heart rate.

Ectopic pacemaker

An abnormal pacemaker that generates an action potential outside of the SA node.

Electrocardiogram (ECG or EKG)

A test to detect electrical activity of the heart.

P wave

The wave on an ECG representing atrial depolarization.

QRS complex

The wave on an ECG representing ventricular depolarization.

T wave

The wave on an ECG representing ventricular repolarization.

Pathophysiology

The study of disordered physiological processes.

Cardiac constrictions

Phenomena where the heart chambers momentarily lose their ability to pump effectively.

Calcium ions

Electrolytes crucial for heart contraction and signaling.

Refractory period

The period during which the heart muscle cannot be stimulated to contract again.

Desmosomes

Structures that provide adhesion between cardiac muscle cells.

Gap junctions

Protein channels that allow the passage of ions and electrical signals between cells.

Atrial systole

The contraction of the atria pushing blood into the ventricles.

Ventricular systole

The contraction of the ventricles pushing blood into the arteries.

Resting membrane potential

The electrical potential across the cell membrane when the cell is not firing.

Intercalated discs

Specialized connections between cardiac cells that facilitate electrical impulses.

Cardiomyocytes

Cardiac muscle cells responsible for the heart's contraction.

Tissue perfusion

The flow of blood to supply the tissues with nutrients and oxygen.

Ventricular diastole

The phase of the cardiac cycle when ventricles are relaxed and filling with blood.

Atrial diastole

The phase of the cardiac cycle when atria are relaxed.

Isovolumetric contraction

Phase in the cardiac cycle when the ventricles contract but no blood is ejected.

Flow of blood

The movement of blood through the circulatory system.

Aortic arch

The portion of the aorta that bends between the ascending and descending aorta.

Pulmonary circuit

The pathway of blood between the heart and lungs.

Systemic circuit

The pathway of blood between the heart and the rest of the body.

Mitral valve

The heart valve between the left atrium and left ventricle.

Tricuspid valve

The heart valve between the right atrium and right ventricle.

Pulmonary valve

The valve that opens into the pulmonary artery from the right ventricle.

Aortic valve

The valve that opens into the aorta from the left ventricle.

Ventricular filling

The process of blood entering the ventricles from the atria.

Diastolic pressure

Pressure in the arteries when the heart rests between beats.

Systolic pressure

Pressure in the arteries during heart contraction.

Cardiac reserve

The difference between resting and maximal cardiac outputs.

End-diastolic volume (EDV)

The volume of blood in the ventricles at the end of diastole.

End-systolic volume (ESV)

The volume of blood remaining in the ventricles after contraction.

Deoxygenated blood

Blood that is lacking in oxygen, returning to the heart from the body.

Oxygenated blood

Blood rich in oxygen, pumped from the heart to the body.

Pulmonary veins

Veins that return oxygenated blood from the lungs to the left atrium of the heart.

Superior vena cava

The large vein that carries deoxygenated blood from the upper body to the right atrium.

Inferior vena cava

The large vein that carries deoxygenated blood from the lower body to the right atrium.

Coronary sinus

A collection of veins that join to form a large vessel that collects blood from the heart muscle.

Chamber of the heart

One of the four separate compartments of the heart (atria and ventricles).

Compartmentalization of heart

The division of the heart into chambers to prevent mixing of oxygenated and deoxygenated blood.

Action potential

A momentary change in electrical potential on the surface of a cell.

Resting potential

The stable, negative charge of a cell when it is not generating an action potential.

Main arteries

Major blood vessels that carry oxygenated blood from the heart to the body.

Major veins

Large blood vessels that carry deoxygenated blood back to the heart.

Blood flow direction

The path blood takes as it traverses the circulatory system.

Valve function

To ensure unidirectional blood flow through the heart and vessels.

Valve types

Includes AV valves and semilunar valves.

Coronary circulation path

The route blood takes to supply the heart itself.

Plateau phase

In a cardiac action potential, the period during which the cell remains depolarized.

Calcium influx

The entrance of calcium ions into the cells, critical for muscle contraction.

Skeletal muscle vs cardiac muscle

Cardiac muscle has a longer action potential duration than skeletal muscle.

Domestic serenity

A term referring to the peaceful state of the heart when it is at rest.

Hemodynamic factors

Factors that influence blood flow properties.

Activity level

Physical exertion level which affects heart rate.

Electrical events

Changes in electrical potential that coordinate heartbeat.

Arterial blood flow

The movement of blood through arteries leading away from the heart.

Blood volume

Total amount of blood circulating in the body.

Electrophysiological characteristics

Properties of heart cells that enable them to generate electrical impulses.

Fluid mechanics

The study of how fluids move and behave.

Blood vessel structure

The composition of arteries, veins, and capillaries.

Venous return

The flow of blood back to the heart from the body.

Autonomic nervous system

The part of the nervous system that controls involuntary actions.

Sympathetic stimulation

Nervous signals that increase heart rate and strength of contractions.

Parasympathetic stimulation

Nervous signals that decrease heart rate.

Hemodynamics

The dynamics of blood flow.

Medulla oblongata

Part of the brain that controls autonomic functions, including heart rate.

Rheumatic fever

An inflammatory disease that can affect the heart.