Acyanotic Heart Disease and VSD

• Congenital heart disease involves various subtypes with differing clinical signs, investigations, and management strategies.

Acyanotic Lesions

• Acyanotic lesions involve left-to-right shunting, leading to increased pulmonary blood flow and potential pulmonary hypertension.
• Untreated, acyanotic heart disease can result in Eisenmenger syndrome.
• Ejection systolic murmurs typically arise from lesions above the nipple level.
• Pan-systolic murmurs usually originate from lesions below the nipple level.

Ventricular Septal Defect (VSD)

• VSD is the most common congenital heart lesion, accounting for 15-20% of cases and is associated with Down's syndrome.
• Small VSDs may be asymptomatic, while moderate ones cause poor feeding, failure to thrive (FTT), and shortness of breath (SOB).
• Large VSDs lead to poor feeding, FTT, SOB, sweating, and pallor during feeds.
• Clinical findings may include a palpable thrill, enlarged liver, pan-systolic murmur at the lower left sternal border (LLSB), and a loud P2 indicative of pulmonary hypertension.
• Investigation involves pulse oximetry, echocardiography, chest X-ray (CXR) for cardiomegaly and pulmonary edema, and ECG for left ventricular hypertrophy (LVH) or right ventricular hypertrophy (RVH).
• Management includes no repair for small VSDs, diuretics and high-caloric feeds for moderate VSDs, and surgical intervention before 12 months for large VSDs to prevent pulmonary hypertension.

Atrial Septal Defect (ASD)

• ASD is the second most common acyanotic heart lesion (5-10%).
• Patients are typically asymptomatic but some children experience recurrent chest infections.
• Clinical features include an ejection systolic murmur at the upper-left sternal border (ULSB) and a widely fixed splitting of the second heart sound.
• Diagnosis includes pulse oximetry, ECHO to visualize the defect, CXR (usually normal), and ECG showing an incomplete right bundle branch block (RBBB).
• Management involves monitoring for spontaneous closure in small lesions and percutaneous or surgical repair for large defects.

Patent Ductus Arteriosus (PDA)

• PDA accounts for 5-10% of all congenital heart defects, is common in preterm infants.
• Small PDAs are often asymptomatic, moderate PDAs cause congestive heart failure and FTT, and large PDAs result in poor feeding, severe FTT, and recurrent lower respiratory tract infections.
• Clinical signs include bounding pulses, wide pulse pressure, and a continuous machinery murmur at the ULSB.
• Diagnosis is confirmed by 2D echocardiography and Doppler.
• Management options range from spontaneous closure in preterm infants to medical treatment with indomethacin/ibuprofen or surgical intervention with catheter closure or PDA ligation.

Coarctation of the Aorta

• Coarctation of the aorta represents approximately 5% of all congenital heart defects and is associated with Turner's syndrome.
• Symptoms manifest 3-5 days after birth as the ductus arteriosus closes.
• Clinical features include high systolic blood pressure, absent femoral pulses, cold extremities, and a murmur between the scapulae.
• Diagnosis is made via 2D echocardiogram and Doppler.
• Management involves prostaglandin E1 infusion to maintain ductal patency, dopamine or dobutamine to improve contractility, and surgical repair via balloon angioplasty or resection with end-to-end anastomosis.

Cyanotic Lesions

• Cyanotic lesions result from the mixing of deoxygenated blood with oxygenated blood (right → left shunt).
• Differential diagnoses of cyanotic lesions include Tetralogy of Fallot, Transposition of great arteries, Truncus arteriosus, Total anomalous pulmonary venous connection, Tricuspid valve abnormalities, and other conditions like hypoplastic left heart.

Tetralogy of Fallot

• Tetralogy of Fallot involves a ventricular septal defect, overriding aorta, pulmonary stenosis, and right ventricular hypertrophy.
• Symptoms include cyanosis, poor feeding, and sweating during feeds.
• Clinical findings encompass cyanotic "tet" spells and a murmur due to right ventricular outflow tract obstruction (RVOTO).
• Diagnosis is through echocardiography and Doppler, ECG, CXR showing a "boot-shaped heart", and cardiac catheterization.
• Management includes prostaglandin infusion for severe cyanosis, knee-to-chest position, oxygen, morphine, beta-blockers, digoxin, loop diuretics, endocarditis prophylaxis, and surgical repair with a Blalock-Taussig shunt.

Transposition of the Great Arteries (TGA)

• TGA involves the aorta arising from the right ventricle (RV) and the pulmonary artery from the left ventricle (LV).
• Symptoms are cyanosis, poor feeding, and sweating during feeds.
• Diagnosed via fetal ultrasound, echocardiogram, and CXR showing an "egg on a string" appearance.
• Management entails balloon atrial septostomy and an arterial switch procedure.

Innocent Murmurs

• Types of innocent murmurs include Still's murmur, venous hum, and turbulent flow in the pulmonary artery bifurcation.
• Innocent murmurs share the following features: soft, systolic, short, normal S1 and S2 sounds, symptomless, normal special tests (X-ray and ECG), variation with position, and association with sternal depression.

Still's Murmur

• A soft vibratory murmur heard over the lower-left sternal border, common in childhood.

Venous Hum

• Continuous murmur heard loudest over the clavicles, varies with position.

Turbulent Flow in Pulmonary Artery Bifurcation

• Soft ejection systolic murmur caused by turbulent flow in the pulmonary artery bifurcation due to small PA branches.