Heart Structure and Function

The left atrium receives oxygen-rich blood from the lungs and pumps it into the left ventricle through the mitral valve.

The left ventricle pumps oxygen-rich blood to the aorta, which distributes it to the rest of the body.

The mitral valve, also known as the bicuspid valve, is located between the left atrium and the left ventricle. It has two cusps: anterior and posterior.

The tricuspid valve is positioned between the right atrium and the right ventricle. It has three cusps: anterior, septal, and posterior.

The semilunar valves prevent backflow from the great vessels (aorta and pulmonary trunk) into the ventricles.

A forceful, outward movement of the heart's apex, often due to increased pressure within the heart chambers.

A feeling of fluttering, pounding, or racing heartbeats, either regular or irregular.

An abnormal awareness of the heart's beat, caused by an increased volume of blood in the heart chambers.

An increased pressure in the pulmonary arteries, causing a rhythmic forceful pulsing in the chest.

A palpable, vibrating sensation felt over a blood vessel, usually caused by turbulent blood flow within the heart.

The upper chamber of the heart that receives deoxygenated blood from the body through the superior and inferior vena cava.

The lower chamber of the heart that pumps deoxygenated blood to the lungs through the pulmonary valve.

A valve located between the right atrium and right ventricle, controlling blood flow.

A valve located between the right ventricle and pulmonary artery, allowing blood to flow to the lungs.

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

The lowest and outermost point of the heart's pulsation, typically formed by the left ventricle.

Located in the 5th intercostal space, along the midclavicular line (nipple line) on the chest. This is where you can feel the heart beat.

A condition where the right ventricle is enlarged, causing the apex to shift outwards and become less forceful.

A condition where the left ventricle is enlarged, causing the apex to shift outwards and downwards, and becoming more forceful.

A condition where the apex is felt only in one intercostal space, typically associated with Left Ventricular Hypertrophy.

The first heart sound, 'S1', is produced by the closure of the mitral and tricuspid valves.

The second heart sound, 'S2', is produced by the closure of the aortic and pulmonary valves, marking the end of ventricular systole.

A palpable murmur, known as a thrill, is a vibration felt when the heart sounds are very loud.

Mitral murmurs often become louder when a patient lies on their left side, as this increases blood flow across the mitral valve.

The intensity of a murmur is graded on a scale from 1 to 6. Grades 1-3 are audible only with a stethoscope, while grades 4-6 are accompanied by a palpable thrill.

A type of congenital heart defect where blood flow is directed from the left side of the heart to the right side, often causing an overload of the right ventricle and pulmonary circulation.

A condition where the ductus arteriosus, a blood vessel connecting the aorta and pulmonary artery, remains open after birth, allowing blood to bypass the lungs.

A group of congenital heart defects characterized by a hole in the ventricular septum, the wall separating the two ventricles of the heart.

A condition where the great arteries, the aorta and pulmonary artery, are switched, resulting in oxygen-poor blood circulating to the body.

A congenital heart defect where the aortic valve is narrowed, restricting blood flow from the left ventricle to the aorta.

Echocardiography with Doppler is a primary diagnostic tool used to investigate congenital heart disease, providing detailed images of the heart's structure and function.

Fetal circulation is a unique circulatory system in the developing fetus, utilizing specialized structures like the foramen ovale and ductus arteriosus to bypass the lungs.

An electrocardiogram (ECG) is a non-invasive test that records the electrical activity of the heart, providing insights into heart rhythm and function.

The fetal circulation diagram illustrates the path of blood flow in the fetus, highlighting key structures like the umbilical vein, ductus arteriosus, and foramen ovale.

The inferior vena cava carries deoxygenated blood from the lower body to the right atrium of the heart.

A congenital heart defect characterized by four specific anomalies: pulmonary stenosis, ventricular septal defect, overriding aorta, and right ventricular hypertrophy. It results in shunting of blood from the right ventricle to the aorta, bypassing the lungs, leading to oxygen-deficient blood circulation.

Narrowing of the pulmonary valve or the outflow tract of the right ventricle, obstructing blood flow to the lungs.

The aorta, the main artery carrying blood from the heart to the body, sitting directly over the VSD, receiving blood from both ventricles.

A thickening of the right ventricle wall due to the increased workload caused by pulmonary stenosis and the VSD.

Deoxygenated blood from the body travels to the heart via the umbilical cord, while oxygenated blood from the placenta flows back to the fetus through the umbilical cord into the heart. This results in mixed blood flowing from the heart to the body.

The ductus arteriosus remains open after birth, allowing oxygenated blood from the aorta to mix with deoxygenated blood from the pulmonary artery. This results in a mixture of oxygenated and deoxygenated blood.

These defects cause blue skin discoloration (cyanosis). Some common examples include Tetralogy of Fallot, resulting in symptoms like squatting, cyanosis, clubbing, and syncope.

These defects do not usually cause cyanosis. Examples include Patent Ductus Arteriosus (PDA), Atrial Septal Defect (ASD), and Ventricular Septal Defect (VSD). These defects usually lead to fatigue, murmurs, and an increased risk of complications.

Tetralogy of Fallot is a complex heart defect that causes a mixture of oxygenated and deoxygenated blood to flow into the body. This leads to cyanosis and other symptoms like squatting, clubbing, and syncope.

Atrial contraction forces blood into the ventricles, marking the start of the cardiac cycle.

The ventricles contract, closing the AV valves, and pushing blood into the aorta and pulmonary artery.

The semilunar valves close, preventing blood from flowing back into the ventricles, while blood returns to the atria.

The heart chambers completely relax, allowing passive filling of the ventricles with blood.

Depolarization of the ventricles, causing them to contract, and is represented by an ECG wave.