Cardiology: Congenital Heart Defects and Diseases

Pediatric Cardiology

• Congenital Heart Diseases (CHD): 8 per 1000 live births have significant cardiac malformation
• Risk Factors: Genetic predisposition, exposures during pregnancy (drugs or disease), chromosomal abnormalities
• Acyanotic Congenital Heart Diseases (ACHD): 80% of all CHD; left-to-right shunts
• Commonest Lesions: Ventricular septal defect (VSD), patent ductus arteriosus (PDA), atrial septal defect (ASD)
• General Clinical Features (with left-to-right shunts): High pulmonary blood flow, poor feeding, recurrent chest infections & wheezes, recurrent heart failure, and growth failure
• Heart Failure: Usually doesn't occur in full-term neonates, but can occur in infancy as pulmonary vascular pressure declines.
• ACHD without shunts: Obstructive lesions e.g. Aortic coarctation, Aortic stenosis, Pulmonary stenosis

Ventricular Septal Defect (VSD)

• Definition: Defect anywhere in the interventricular septum
• Hemodynamics: Blood shunted from left ventricle (higher pressure) to right ventricle (lower pressure). Increased pulmonary blood flow. Pulmonary congestive symptoms. Volume overload on right ventricle, left atrium, and left ventricle

Atrial Septal Defect (ASD)

• Definition: Defect in the inter-atrial septum

Patent Ductus Arteriosus (PDA)

• Definition: Persistent fetal duct connecting the aorta & the pulmonary artery
• Association: Congenital rubella syndrome & prematures
• Medical Closure: IV indomethacin in the 1st week of life

Atrioventricular Septal Defect (AVSD)

• Definition: Defect in the atrioventricular septum; complete defect
• Association: Common with Down syndrome

Acyanotic Heart Disease

• General Manifestations: Usually asymptomatic, discovered if the defect small, dyspnea during suckling, recurrent chest infections (sign of pulmonary congestion), physical examination (tachypnea, dyspnea, tachycardia, and enlarged tender liver)
• Complications: Infective endocarditis, higher risk of Eisenmenger syndrome, heart failure
• Treatment: Medical - control heart failure, antibiotics for chest infections, avoid infective endocarditis, follow-up Surgical -if symptomatic large defects with uncontrollable heart failure or growth failure

Cyanotic Congenital Heart Disease (CCHD)

• Fallot Tetralogy: Commonest cyanotic CHD, with decreased pulmonary blood flow, composed of pulmonary stenosis, right ventricle hypertrophy, ventricular septal defect (VSD), aortic dextroposition
• Clinical Picture: Central cyanosis, cyanotic clubbing of fingers and toes, growth retardation, squatting position for relief of dyspnea, paroxysmal hypercyanotic spells (hypoxic)

Investigations

• Chest X-ray, Echocardiography, ECG, CBC

Complications of ARF

• Mitral stenosis, heart failure, cardiomyopathy
• Eradicate group A B-Streptoccoci (oral penicillin or erythromycin for 10 days , or a single intramuscular injection of benzathine penicillin )
• Typical migratory arthritis (bed rest for 2 weeks , Anti-inflammatory drug (Salicylates, dose: 100mg/kg/day, for 3-5 days then 50 mg/kg/d for 3 weeks )
• Carditis (bed rest, and anti-inflammatory drugs (corticosteroids or salicylates) )

Infective Endocarditis

• Definition: Infection of the valves and endocardium
• Risk Factor: Prosthetic cardiac valve, previous infective endocarditis, congenital heart disease (except ASD), permanently damaged valves due to rheumatic heart disease.
• Causative Organisms: Streptococcus viridans (50%), Staphylococcus aureus and epidermidis, Group D enterococci, fungal.
• Pathogenesis: Implantation, local inflammation, formation of friable vegetations, composed of platelets, fibrin, inflammatory cells and organisms
• Clinical Picture: Suggestive of risk factor or bacteremia, General manifestations

Heart Failure

• Definition: Heart is unable to pump enough blood to meet body needs
• Causes: Congenital heart disease, rheumatic heart disease, myocarditis, infective endocarditis, severe anemia, nutritional deficiencies (e.g., kwashiorkor), dysrhythmia, dilated cardiomyopathy, and pulmonary disease (cor pulmonale).
• Clinical Features: Infants (poor feeding, dyspnea while sucking, excessive sweating, poor weight gain), older children (dyspnea on exertion, effort intolerance, ankle edema)
• Signs: Tachycardia, gallop rhythm & weak pulse, cold, sweaty skin, cardiomegaly
• Systemic congestion: Enlarged tender liver, congested neck veins, edema in ankles or sacrum(in bed ridden), and periorbital (in infants)

Anemia

• Definition: Reduction of hemoglobin and/or RBCs count below the average value for age and sex, interfering with oxygen-carrying capacity of blood
• General features: Fatigue, headaches, faintness, palpitations, breathlessness, angina, intermittent claudication
• Signs: pallor, tachycardia (palpitation), hemic murmurs (functional, systolic), Heart Failure in severe anemia (hemoglobin < 4 gm/dl)
• Classification : Morphologic, Etiologic (Decreased production, Increased destruction)
• Decreased Production: Pure red cell anemia, Aplastic anemia, Marrow infiltration
• Specific Factor Deficiencies: Iron, copper, vitamins (B1, B6, folic acid and B12), protein
• Increased Destruction: Membrane defects (spherocytosis, elliptocytosis), Hemoglobinopathy (a-thalassemia, B-thalassemia, Sickle cell disease), Enzymatic defects (G6PD deficiency, pyruvate kinase deficiency), Immunologic, Non immunologic (DIC, Hemolytic uremic syndrome (HUS), renal vein thrombosis (RVT), artificial/calcified cardiac valves, Disseminated Cancer), Thrombotic thrombocytopenic purpura (TTP), Septicemia, drugs, malaria, march hemoglobinuria, hypersplenism

Iron Deficiency Anemia (IDA)

• Incidence: Most common cause of anemia in pediatrics.
• Causes: Decreased intake (delayed weaning, low iron content in breast milk or unfortified animal milk), Decreased iron absorption (excess tea, phytate, antiacids, achlorhydria, malabsorption syndromes), Decreased iron stores (iron-deficient pregnant, perinatal blood loss, premature infants), Increased loss (occult blood loss due to ankylostoma, peptic ulcer, polyps, GERD, cow milk protein allergy, Meckle's diverticulum, drug-induced gastritis, esophageal varices), Increased requirements (rapid growth in preterm/adolescent, congenital cyanotic heart disease due to polycythemia)
• Clinical picture: Asymptomatic in mild cases, mild anemia manifestations (anorexia, pallor) and systemic manifestations (decreased alertness, learning & concentration span, atrophic glossitis, angular stomatitis, brittle nails, koilonychia, palpable spleen, pica)
• Investigations: CBC, stool analysis, GIT barium study, endoscopy, tests for achlorhydria, workup for malabsorption/hemorrhagic diseases

Megaloblastic Anemia (Vitamin B12 & Folic Acid deficiency)

• Definition: Anemia with megaloblasts in bone marrow and macrocytes (large RBCs) in peripheral blood
• Vitamin B12 Sources: Animal origin (milk, meat)
• Vitamin B12 Requirements: 5-20 µg/day
• Vitamin B12 Absorption: Intrinsic factor (IF) released by gastric parietal cells binds to B12 → B12/IF complex → absorbed from terminal ileum.
• Folic acid Sources: Animal and plant sources (green leaves, fruits)
• Folic acid Requirements: 20-50 µg/day
• Causes: Decreased intake/absorption(infants (breast fed to vegetarian mums), malabsorption syndrome, intrinsic factor defect), Defective transport (transcobalamin II deficiency), Increased requirement (premature, pregnancy).
• Clinical Picture: Hematologic (anemia (anorexia, pallor, tiredness, slight jaundice), advanced megaloblastic anemia or thrombocytopenic purpura and leucopenia, mild hepatosplenomegaly), Gastrointestinal (atrophic glossitis, beefy red glazed tongue, atrophic gastritis, dyspepsia, vomiting, risk of stomach cancer, atrophy of intestinal mucosa, abdominal pain, chronic diarrhea)

Thalassemia

• Definition: Autosomal recessive disorders due to defective globin chain production
• Types: ą-thalassemia (one/two/three/four genes missing, resulting in mild to moderate microcytic hemolytic anemia, hemoglobin H disease, and fetal hydrops), B-thalassemia (one/two genes mutation, resulting in thalassemia trait, thalassemia major, thalassemia intermedia)
• Clinical Picture: Progressive anemia, jaundice, thalassemic facies, organomegaly, hemosiderosis, cardiac complications.

Sickle Cell Disease

• Etiology: Autosomal recessive disorder, single amino acid substitution (valine for glutamic acid) in the 6th position of the B-globin chain, resulting in abnormal hemoglobin (HbS)
• Clinical Picture: Features of anemia and chronic hemolysis, renal disorders (proteinuria, nephrotic syndrome, chronic renal failure)
• Crises: Aplastic, hemolytic, megaloblastic, hyperhemolytic, vaso-occlusive (painful) crisis
• Investigations: Anemia (low Hb & Ht values), chronic hemolysis (RBC survival and erythropoiesis), cause

Hemophilia A (classical hemophilia)

• Definition: Sex-linked recessive coagulation disorder due to deficiency of factor VIII
• Clinical Picture: Unusual bleeding from circumcision site or umbilical stump, external bleeding (epistaxis, dental/mouth bleeding, GIT bleeding, hematuria, easy bruising, ecchymotic patches, hematomas, muscle hematoma, intracranial hemorrhage, retropenitonal, hemothorax)
• Investigations: Prolonged clotting time, prolonged aPTT, normal PT, normal bleeding time, low FVIII-C assay (diagnostic)
• Treatment: Primary prophylaxis (regular FVIII replacement 20 unit/kg 3 times a week), treatment of bleeding episodes/peri-operative (Factor VIII replacement)

Acute Pharyngitis

• Causes: Viral or bacterial (group A hemolytic streptococci),
• Complaint: Fever, anorexia, malaise, sore throat, dysphagia
• Clinical picture: Red, congested throat, inflamed tonsils with white or yellow exudates, enlarged tender lymph nodes, associations (conjunctivitis, minute vesicles and ulcers)
• Treatment: Symptomatic care for fever, e.g., 10 days course of antibiotics (Zithromax or penicillin V)

Acute Otitis Media (AOM)

• Risk factors: Eustachian tube obstruction, edema in upper respiratory tract infections, impaired host immune defenses, bottle feeding, genetic susceptibility
• Causes: Viral (complication of bronchiolitis), Bacterial (H. influenza, pneumococci, moraxella catarrhalis)
• Clinical picture: Fever, earache (irritability, rubbing ears in infants), otoscopic examination (congested, bulging drum, effusion, perforated drum with discharge)
• Complications: Mastoiditis, chronic ear infection.
• Treatment: -Symptomatic (pain and fever relief [Ibuprofen or acetaminophen]) Specific: Antibiotics (Amoxicillin-clavulanate enhanced strength, Ceftriaxone, Cefdinir, or Cefpodoxime). Surgical intervention (tympanocentesis and drainage or tympanostomy tubes)

Acute Sinusitis

• Major risk factors: Upper respiratory tract infections, immunodeficiency
• Causes: Mixed infections, same as otitis media
• Clinical picture: Fever, headache, purulent/mucopurulent nasal discharge, postnasal discharge, cough, nasal obstruction, halitosis (fetid breath odor), diminished smell, periorbital edema
• Investigations: Culture and sensitivity of sinus aspirate, plain X-ray/CT skull
• Treatment: Symptomatic (pain and fever relief [paracetamol]), specific (antibiotics for at least 10 days or 7 days after symptom resolution - high-dose amoxicillin or amoxicillin/clavulanate; alternatives: Ceftriaxone, Cefdinir, Cefpodoxime, Cefixime, Cefuroxime), saline nasal washes/sprays to liquefy secretions, and act as a mild vasoconstrictor

Acute Infectious Stridor (Laryngotracheobronchitis/Croup)

• Cause: Viral (parainfluenza types 1, 3; RSV, influenza, adenovirus; corona virus)
• Affects: Children 6 months - 6 years in early winter
• Presentation: Upper respiratory catarrh (rhinitis; low-grade fever), croupy, barking cough, hoarseness of voice, toxic appearance.
• Management: Most cases respond to home treatment; indications for hospitalization include progressive stridor and severe stridor at rest.
• Treatment: - Oxygen for oxygen desaturation, - Nebulized epinephrine, - Oral corticosteroids (Dexamethasone 0.6 mg/kg orally or intramuscularly as a single dose).

Acute Epiglottitis (Supraglottitis)

• Causes: Infection of the epiglottis (Haemophilus influenza type B, Streptococcus pyogenes, Streptococcus pneumoniae, nontypeable H. influenzae, Staphylococcus aureus).
• Clinical picture: Peak age 2-7 years, toxic child with high fever, drooling of saliva (severe dysphagia), muffled voice, mild stridor, little or no cough. Upright posture and hyperextended neck in an attempt to maintain airway.
• Management: Medical emergency; admission to PICU, secure airway before any maneuver.
• Treatment: Endotracheal tube or tracheostomy, antibiotics (Ceftriaxone, Cefotaxime, or Meropenem pending culture and sensitivity results), maintenance of supportive care.

Pneumonia

• Definition: Infection of the lower respiratory tract, involving the airways and parenchyma, causing alveolar space consolidation.
• Anatomic Classification: Lobar, broncho-, interstitial pneumonia
• Etiologic Classification: Bacterial (Gram-positive [Streptococcus pneumoniae, group B and A streptococci, Staphylococcus aureus]; Gram-negative [Haemophilus influenzae, Legionella, Klebsiella]), viral (Respiratory syncytial virus [RSV], parainfluenza, influenza, adenovirus, human metapneumovirus, Corona virus), atypical (Mycoplasma pneumoniae, Chlamydophila pneumoniae, Chlamydia trachomatis).
• Symptoms: Variable onset (acute, subacute or gradual), fever, malaise, toxemia, abdominal pain (referred from lower lobe pneumonia), dry then productive cough, dyspnea, and grunting; respiratory distress, tachypnea, nasal flaring, retractions, grunting, cyanosis in severe cases.
• Investigations: Chest X-ray, ultrasonography, contrast CT scan, WBC count, acute phase reactants (ESR and C-reactive protein), organism isolation.
• Complications: Pleural effusion, empyema, pyopneumothorax, lung abscess, unresolved pneumonia, meningismus (especially with right upper lobe pneumonia), heart failure, distant infections (septicimia, meningits, pericarditis), paralytic ileus.
• Treatment: Supportive (bed rest, humidified oxygen, symptomatic treatment, treatment of complications), specific (antibiotics [empirical/specific]; antivirals).

Pertussis (Whooping Cough)

• Etiology: Bacteria (Bordetella pertussis, Bordetella parapertussis)
• Clinical picture: 3 stages (catarrhal [1–2 weeks, mild fever, coryza, conjunctivitis, cough], paroxysmal [4–6 weeks, frequent coughs ending with whooping inspiration], convalescent [1–2 weeks, gradual decline])
• Diagnosis: History of contact, nasopharyngeal swab (direct fluorescent antibody staining, PCR, or culture)
• Treatment: General (isolation, bed rest, avoid triggers, small frequent feeds, or tube feeding, cough sedatives), Antibiotics (azithromycin 10 mg/kg/day for 5 days or clarithromycin 15 mg/kg/day for 7 days or erythromycin 50 mg/kg/day for 10 days)

Measles (Rubeola)

• Etiology: RNA virus (Paramyxoviridae family).
• Clinical Picture: The disease features a catarrhal stage (high fever, non-purulent conjunctivitis, coryza, cough, sore throat, Koplik's spots), and an eruptive stage (maculopapular rash that begins behind the ears and spreads centrifugally).
• Prevention: MMR vaccine (at 9 months, the first dose and at 12-18 months second dose in USA at school age).
• Treatment: Supportive (bed rest, isolation, symptomatic care, antipyretics, care of feeding, soft diet, and fluids), complications (antibiotics for secondary infections).

Rubella (German Measles)

• Etiology: RNA virus (Togaviridae).
• Clinical Picture: Mild fever, mild nasopharyngitis, characteristic tender lymphadenopathy (appears 1 day prior to the rash). The eruptive stage is characterized by a maculopapular rash (starting on the face and spreading to the trunk and limbs), which fades after 3 days.
• Prevention: MMR vaccine.
• Treatment: Symptomatic care.

Chickenpox (Varicella)

• Etiology: DNA virus (Varicella-zoster virus [VZV]), causing varicella or chickenpox.
• Transmission: Droplet infection or contact with skin lesions.
• Clinical picture: Prodroma (fever, malaise, anorexia), rash (starts on the face then spreads to the trunk and limbs, erythematous macules that evolve into vesicles and pustules, characteristic distribution pattern that spreads centripetally).
• Treatment: Supportive (antipruritic therapy [calamine lotion, antihistamines], symptomatic care, antipyretics, antibiotics for secondary infections) and antiviral acyclovir. Prevention: Live attenuated chickenpox vaccine.

Mumps

• Etiology: RNA virus (Paramyxoviridae).
• Transmission: Droplet infection.
• Clinical picture: Characterized by painful parotid gland swelling.
• Complications: Orchitis, mastitis, pancreatitis.
• Treatment: Supportive care; isolation; symptomatic treatment (warm/cold packs, analgesics); treatment of complications

Internal Medicine-Nephrology

• Nephrons: Functional units of the kidneys carrying out urine formation. Each nephron comprises of glomerulus (tuft of capillaries) and renal tubules.
• Renal Functions: Control body fluid, excretion of waste products (BUN, creatinine, H+, excess K+, drugs), regulation of acid-base balance, and hormonal function (erythropoietin, vitamin D).
• Acute Renal Failure (ARF): Rapid deterioration of renal function, characterized by increased waste products and oliguria (reduced urine output)
• Etiology: Pre-renal (60% - reduced renal blood flow - hypovolemia, heart failure, hypoalbuminemia), Renal (30% - damage to the kidney tissue - glomerulonephritis, acute tubular necrosis, pyelonephritis, vascular disorder [renal vein thrombosis]), Post renal (10% - obstruction to urine outflow - kidney stones, tumors, trauma).
• Clinical Picture (in all types): Oliguric phase (water retention, edema, acidotic breathing, hyperkalemia , ↑urea), polyuric phase, recovery.
• Investigations: Urine analysis (oliguria, microscopy), renal function tests (urea, creatinine), arterial blood gases, electrolytes
• Management: Correcting underlying cause, maintaining fluid balance, managing electrolytes, and treating complications (dialysis may be necessary).

Chronic Kidney Disease (CKD)

• Definition: Progressive irreversible deterioration of kidney function for >3 months with development of the clinical syndrome of uremia.
• Causes: Diabetic nephropathy, systemic hypertension, chronic glomerulonephritis, chronic pyelonephritis, obstructive uropathy, analgesic nephropathy, congenital polycystic kidneys
• Stages: Classified according to GFR.
• Pathophysiology: Failure of kidneys to perform normal excretory, metabolic, and endocrine functions.
• Clinical picture: Non-specific (fatigue, weakness, pruritus, shortness of breath [dyspnea]), Specific signs (anorexia , pallor, ecchymoses, pale conjunctiva, shortness of breath during exertion, retrosternal pain with inspiration, rales, pleural effusion, hypertension, cardiomegaly, friction rub , anorexia, weight loss, nausea ,vomiting, restlessness, generalized irritability, stupor, asterixis, myoclonus).
• Complications: Hyperkalemia, acid-base disorders, cardiovascular problems (hypertension, pericarditis, congestive heart failure), hematologic problems (anemia, coagulopathy), bone complications (renal osteodystrophy, osteomalacia), neurologic syndromes, and endocrine problems.
• Investigations: Complete blood count (CBC), serum urea and creatinine, serum electrolytes, serum bicarbonate, urine analysis, serum calcium, phosphorus, PTH, vitamin D.

Nephrotic Syndrome

• Definition: Clinical and laboratory condition with nephrotic-range proteinuria (>3.5 g/24 hours), hypoalbuminemia, generalized edema, and hyperlipidemia.
• Causes: Idiopathic (minimal change disease), genetic causes, infections (post-streptococcal glomerulonephritis), diseases (DM, SLE, etc), tumors (Hodgkin's Lymphoma), Systemic, drugs.
• Pathogenesis: increased glomerular permeability (escape of proteins). Dec in serum protein → ↓ plasma osmotic pressure, ↑fluid retention → edema
• Clinical Picture: Generalized edema (periorbital puffy face, limbs, ascites, pleural effusion), anorexia, abdominal pain, hypertension
• Complications: Hypovolemia (due to diuretics use or diarrhea), infections, acute renal failure, intravascular clotting
• Investigations: Urine analysis (proteinuria, lipiduria, cellular casts), biochemical tests (serum albumin, cholesterol, electrolytes), CBC, complement component 3 (C3), renal biopsy

Urinary Tract Infection (UTI)

• Causes: Upper UTI (acute and chronic pyelonephritis), Lower UTI (acute and chronic cystitis, urethritis), Asymptomatic bacteriuria, septicaemia
• Risk factors: Female gender, uncircumcised boys, obstructive uropathy, instrumentation
• Common Organisms: Gram-negative bacteria (E. coli), Proteus, Pseudomonas
• Clinical Picture: (neonate) sepsis, (infant/child) fever, urgency, dysuria (painful urination), frequency, suprapubic pain, secondary nocturnal enuresis, hematuria
• Investigations: Urinalysis and culture, urine sample (mid-stream), indicators of upper UTI (leukocytosis, neutrophilia, elevated serum ESR and C-reactive protein)
• Imaging: Ultrasound of kidneys and bladder
• Treatment: Antibiotics (empirical and specific, 2 to 4 days IV then oral antibiotics). Supportive care (adequate hydration, diet, rest)

Meningitis

• Definition: Inflammation of the membranes covering the brain and spinal cord.
• Causes: Bacterial (E. coli, Listeria monocytogenes, group B and A streptococci, Nesseria meningitides, Pneumococci, Staphylococcus, H. influenza), Aseptic (viral, fungal), Tuberculous
• Clinical picture: High fever, poor feeding, rose spots, increased intracranial pressure (bulging fontanels, headache, severe bursting headache, projectile vomiting, neck rigidity), meningeal irritation, neurologic signs (drowsiness, convulsions, coma).
• Complications: SIADH, increased intracranial pressure (can cause brain edema or herniation), cranial nerve lesions, peripheral circulatory complications (Waterhouse-Friderichsen syndrome), septicemia, shocke, extensive purpura, adrenal hemorrhage
• Investigations: CBC, blood culture (for bacterial cause), C-reactive protein (CRP), ESR, CSF examination , and lumbar puncture

Seizures

• Definition: Transient, paroxysmal, time-limited, involuntary disturbance of brain function, manifested by abnormal motor, sensory, behavioral or autonomic activities; convulsions (uncontrollable muscle contractions)
• Causes: Acute seizures (Febrile seizures, first epileptic fit, symptomatic seizures - CNS causes like infection or irritation; toxic causes such as tetanus, drugs, lead; other causes; hypoxia or ischemia, hypertension, metabolic imbalances), Recurrent seizures (Epilepsy, symptomatic seizures - degenerative brain diseases, chronic metabolic causes, inborn errors of metabolism, hepatic/uremic encephalopathy).
• Febrile Seizures: Seizures in children due to a rapid rise in body temperature.
• Investigations: EEG, metabolic screen (Na, Ca, Mg, glucose), CSF examination, MRI, or CT brain, ECG

Cerebral Palsy

• Definition: Group of permanent movement and posture disorders resulting from non-progressive lesions to the developing fetal or infant brain.
• Causes: Prenatal (80% - antenatal infections, congenital malformations, fetal asphyxia), Natal (10% - birth asphyxia, birth trauma), Postnatal (10% - VLBW with intracranial hemorrhage, meningitis, encephalitis)
• Clinical Types: Spastic diplegia, spastic hemiplegia, spastic quadriplegia, spastic monoplegia, spastic paraplegia, Ataxic, extrapyramidal (dyskinetic; athetoid), Atonic, Mixed
• Diagnosis: Thorough history and physical examination, exclude other progressive CNS diseases. investigations (CT, MRI, TORCH screen, genetic evaluation, metabolic screen)
• Treatment: Multidisciplinary approach involving various specialists (physical and occupational therapists, speech pathologists).

This quiz covers important definitions related to congenital heart defects and various heart-related diseases. Test your knowledge on conditions such as ventricular septal defect, atrial septal defect, and acute rheumatic fever. Ideal for students studying cardiology or medical professionals looking to refresh their understanding.