Rapid Review·Cardiovascular
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HY Approach
T1Must knowApproach to Congenital Heart Disease
Focus on
Three physiologies decide the presentation: left-to-right shunts (tachypnea, sweating with feeds, poor weight gain), right-to-left shunts (cyanosis), and obstructed left-sided output (shock when the duct closes). Match the syndrome or exposure to its lesion, know the newborn pulse-oximetry screen, and recognize the classic exam and chest-film signatures.
Key takeaways
How congenital heart disease presents
Prenatal
most defects are diagnosed on the 20-week anatomy scan.After birth
the rest present with faltering growth, cyanosis, or fatigue and sweating with feeds (the infant's heart failure).Critical congenital heart disease screen for every newborn
pulse oximetry of the right hand and a foot.- A cyanotic defect is suspected if any reading is under 90 percent or the foot reads significantly lower than the hand.
Diastolic or continuous murmur
any infant with one gets an echocardiogram.| Cause | Clinical features | Examples |
|---|---|---|
| Left-to-right shunting (acyanotic, pulmonary over-circulation) | Tachypnea, poor weight gain, sweating with feeds; symptoms appear at 1 to 2 months as pulmonary resistance falls | Ventricular Septal Defect, Atrial Septal Defect, Patent Ductus Arteriosus |
| Right-to-left shunting (cyanotic) | Cyanosis unresponsive to oxygen; hours (transposition), days (duct-dependent), months (tetralogy spells) | Transposition of the Great Arteries, Tetralogy of Fallot, Tricuspid Atresia, Total Anomalous Pulmonary Venous Return, Truncus Arteriosus |
| Interrupted left-ventricular output (duct-dependent systemic flow) | Well at birth, then pallor or shock with severe acidosis when the duct closes | Coarctation of Aorta, Hypoplastic Left Heart Syndrome |
Associations and the duct-dependent newborn
| Association | Defects |
|---|---|
| Fetal alcohol syndrome | Ventricular and atrial septal defects, patent ductus, tetralogy of Fallot |
| Congenital rubella | Patent ductus arteriosus, pulmonary artery stenosis, septal defects |
| Down syndrome | Atrioventricular septal (endocardial cushion) defect, ventricular and atrial septal defects |
| Infant of a diabetic mother | Transposition of the great arteries, truncus arteriosus, tricuspid atresia, ventricular septal defect |
| Marfan syndrome | Mitral valve prolapse, thoracic aortic aneurysm and dissection, aortic regurgitation |
| Prenatal lithium | Ebstein anomaly |
| Turner syndrome | Bicuspid aortic valve, coarctation of the aorta |
| Williams syndrome | Supravalvular aortic stenosis |
| 22q11 deletion (DiGeorge) | Truncus arteriosus, tetralogy of Fallot |
Duct-dependent lesions
prostaglandin E1 first.High-yield findings by diagnosis
| Diagnosis | Key findings |
|---|---|
| Tricuspid atresia, total anomalous venous return, hypoplastic left heart, coarctation | Progressive cyanosis in the first 2 weeks as the duct closes |
| Transposition of the great arteries | Cyanosis at birth, tachypnea; a loud single S2 (anterior aorta), murmur absent or faint; egg-shaped heart with a narrow superior mediastinum |
| Total anomalous pulmonary venous return | Cyanosis and tachypnea in the first week, prominent neck veins; snowman (figure-of-eight) silhouette with large pulmonary vascularity |
| Tetralogy of Fallot | Dyspnea with feeds, hypercyanotic "tet" spells relieved by squatting; harsh systolic murmur at the left upper sternal border with a single S2, right-ventricular impulse and thrill; boot-shaped heart |
| Truncus arteriosus | Cyanosis, wide pulse pressure and bounding pulses, harsh systolic murmur with a thrill, loud single S2 |
| Atrial septal defect | Ejection murmur at the left upper sternal border, wide fixed split S2, right-ventricular heave |
| Ventricular septal defect | High-pitched holosystolic murmur at the left sternal border, hyperdynamic apex; cyanosis only late (Eisenmenger) |
| Coarctation of the aorta | Upper-body hypertension, suprasternal pulsations, weak leg pulses with brachial-femoral delay, claudication in older children; ejection or continuous murmur in the back |
Cyanotic disease by age
Infants
cyanosis in the first hours to days is a right-to-left shunt (transposition, truncus, tetralogy, total anomalous return, Ebstein, hypoplastic left heart, tricuspid atresia), often unmasked as the duct closes.Toddlers
a tetralogy not cyanotic in infancy presents as the child who cannot keep up at recess and squats to catch his breath.Young adults
difficult-to-control hypertension with claudication is coarctation.Any age
right heart failure in unrepaired disease means Eisenmenger Syndrome.Vascular rings and endocarditis prophylaxis
Vascular rings
a double aortic arch (Down, DiGeorge, CHARGE) compresses the trachea and esophagus in the first weeks.- Biphasic stridor relieved by arching the neck, dysphagia and choking.
- A lateral film shows anterior tracheal bowing; computed tomography (CT) or magnetic resonance (MR) angiography defines it; surgical division of the minor arch.
Endocarditis prophylaxis
only for unrepaired cyanotic disease, repaired disease with prosthetic material for 6 months (indefinitely with a residual defect), and prior endocarditis (Infective Endocarditis).A 2-week-old who was well at birth is now pale and in shock with severe acidosis and absent femoral pulses. What physiology is this, and what is given before the echocardiogram?
Interrupted left-ventricular output, a duct-dependent systemic lesion (coarctation or hypoplastic left heart) unmasked as the duct closed. Give intravenous alprostadil (prostaglandin E1) before the echocardiogram.
How it's tested
A newborn's screening pulse oximetry reads 88% in the foot and 96% in the right hand: failed critical CHD screen with a preductal–postductal gradient — echocardiogram; think coarctation, PPHN or a duct-level right-to-left shunt.
A 2-month-old who sweats and tires with feeds, breathes fast, and has gained no weight, with a harsh holosystolic murmur: large VSD with pulmonary over-circulation — echo, diuretics, ACE inhibitor, surgical repair.
Infant with Down syndrome and a fixed split S2 with a holosystolic murmur: endocardial cushion (AV canal) defect.
Newborn of a diabetic mother, blue within hours, single S2, no murmur: transposition of the great arteries — PGE1, balloon atrial septostomy, arterial switch.
A 2-week-old in shock with no femoral pulses: critical coarctation or HLHS — prostaglandin E1 now.
Go deeper
Guidelines: 2018 AHA/ACC Adult Congenital Heart Disease Guideline
Related Step 2 pages: Approach to Neonatal Cyanosis, Approach to Pediatric Murmurs, Fetal Circulation & Transition at Birth, Cardiac Embryology Essentials, Ventricular Septal Defect, Tetralogy of Fallot, Transposition of the Great Arteries, Coarctation of Aorta, Eisenmenger Syndrome
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