Pediatric Cardiology: Congenital and Acquired Conditions

These vocabulary flashcards cover pediatric cardiology topics including fetal circulation, inflammatory diseases like myocarditis and endocarditis, cardiomyopathies, congenital heart defects (shunts), and functional disorders such as syncope and rheumatic fever.

Congenital heart disease

Structural, anatomical defects with the heart that are present from birth.

Acquired heart conditions

Conditions that develop during infancy or later in life, often due to infectious or inflammatory causes.

Fetal circulation pressures

In utero, the pulmonary vascular resistance ($PVR$) is high because the lungs are fluid-filled, and the systemic vascular resistance ($SVR$) is low.

Ductus venosus

A fetal shunt that directs oxygenated blood past the liver directly to the inferior vena cava ($IVC$) to preserve oxygen content.

Foramen ovale

A fetal opening between the right and left atria that allows oxygen-rich blood to bypass the lungs and move to the left side of the heart.

Ductus arteriosus

A fetal vessel connecting the pulmonary artery to the aorta, diverting right ventricle output away from high-resistance lungs.

Myocarditis

Inflammation of the middle muscle layer of the heart, usually resulting from viral invasion of the myocytes (e.g., enterovirus or parvovirus).

Endocarditis

Infection of the inner lining and valves of the heart, requiring both damaged endocardium and an infectious agent (usually bacterial) for diagnosis.

Pericarditis

Inflammation of the outer sac around the heart, which can present with precordial chest pain, a friction rub, and muffled heart sounds.

Pulses paradoxus

A pulse change during inspiration versus expiration due to pressure changes within the heart, often found in cardiac tamponade.

Dilated cardiomyopathy

Enlargement and dilation of the heart chambers without thickening of the myocardium, leading to pump failure and systolic dysfunction.

Hypertrophic cardiomyopathy

Asymmetrical septal hypertrophy that causes a thick, stiff ventricle; it is the most common cause of sudden cardiac death in people under $35$, often seen in young athletes.

Restrictive cardiomyopathy

A diastolic problem where stiff ventricles cannot fill or relax, leading to atrial enlargement and often requiring early transplant evaluation.

Noncompaction cardiomyopathy

A condition where the fetal myocardium fails to compact correctly between five to eight weeks in utero, resulting in a spongy, trabeculated left ventricle.

Secondary effects of oxygen ($O_2$)

Oxygen acts as a pulmonary vasodilator, reducing pulmonary vascular resistance ($PVR$).

Atrial septal defect ($ASD$)

A left-to-right shunt characterized by a wide fixed split $S2$ and a systolic ejection murmur.

Ventricular septal defect ($VSD$)

The most common heart defect overall, presenting with failure to thrive and a harsh holosystolic regurgitant murmur.

Patent ductus arteriosus ($PDA$)

Failure of the fetal ductus to close after birth, common in premature infants, resulting in a continuous machinery murmur.

Atrioventricular ($AV$) canal defect

An endocardial cushion defect strongly associated with trisomy $21$ (Down syndrome).

Truncus arteriosus

A congenital defect with a single large vessel and a large $VSD$, associated with DiGeorge syndrome.

Tetralogy of Fallot

The most common cyanotic (right-to-left) shunt, consisting of an overriding aorta, $VSD$, pulmonary stenosis, and right ventricular hypertrophy; it appears as a boot-shaped heart on X-ray.

Transposition of the great arteries ($TGA$)

A defect where the aorta arises from the right ventricle and the pulmonary artery from the left, resulting in two parallel (not series) circulations.

Coarctation of the aorta

A narrowing near the ductus of the artery that can be identified via four-extremity blood pressure checks and absent or weak femoral pulses.

Hypoplastic left heart syndrome ($HLHS$)

A defect with a tiny left ventricle and hypoplastic aorta; it requires staged palliations known as the Norwood, Glenn, and Fontan procedures.

VA ECMO

Veno-arterial extracorporeal membrane oxygenation, which supports both the heart and the lungs by draining a large vein and returning blood to a large artery.

Pulmonary hypertension diagnosis

Defined as a mean pulmonary artery pressure of $\ge 25\,mmHg$ at rest, measured via cardiac catheterization.

Syncope

A transient loss of consciousness and muscle tone due to cerebral hypoperfusion, followed by spontaneous complete recovery.

POTS

Postural orthostatic tachycardia syndrome, characterized by a sustained tachycardia within $10$ minutes of standing without orthostatic hypotension.

Supraventricular tachycardia ($SVT$)

The most common symptomatic dysrhythmia in children, defined by heart rates over $220\,bpm$ in infants or over $180\,bpm$ in children.

Junctional ectopic tachycardia ($JET$)

A common early postoperative complication where the atria and ventricles dissociate, often requiring cooling, pacing, or amiodarone.

Rheumatic fever

A preventable post-strep autoimmune disease following untreated group A strep pharyngitis that scars the heart valves, especially the mitral valve.

Jones Criteria (Major)

Criteria for diagnosing rheumatic fever: joint involvement (polyarthritis), carditis, subcutaneous nodules, erythema marginatum, and Sydenham's chorea.