Congenital Heart Diseases: Acyanotic

Congenital Heart Diseases: Acyanotic

Congenital Heart Diseases: Acyanotic

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Acyanotic CHDs Overview - No Blue Babies!

  • No initial cyanosis; blood shunts Left → Right or faces outflow obstruction.
  • Classification & Presentation:
    • Left-to-Right (L-R) Shunts: ↑ Pulmonary blood flow (PBF).
      • Examples: Ventricular Septal Defect (VSD), Atrial Septal Defect (ASD), Patent Ductus Arteriosus (PDA).
      • Symptoms: Murmur, recurrent respiratory infections, failure to thrive (FTT), signs of Congestive Heart Failure (CHF).
    • Obstructive Lesions: No shunt; restricted ventricular outflow.
      • Examples: Aortic Stenosis (AS), Pulmonary Stenosis (PS), Coarctation of Aorta (CoA).
      • Symptoms: Murmur, exercise intolerance, syncope (AS), differential BP (CoA).

Left-to-Right vs. Right-to-Left Shunts

⭐ Most common congenital heart disease overall, Ventricular Septal Defect (VSD), is acyanotic and an L-R shunt lesion.

VSD & ASD - Septal Shunt Stories

ASD and VSD Anatomy and Transcatheter Closure

FeatureVentricular Septal Defect (VSD)Atrial Septal Defect (ASD)
EpidemiologyMost common CHDCommon CHD; F>M
TypesPerimembranous (most common), muscular, inlet, supracristalOstium secundum (most common), primum, sinus venosus
MurmurHarsh pansystolic, LLSB; thrillEjection systolic, ULSB; 📌 Fixed wide split S2
ECGLVH (mod VSD), BVH (large VSD)RAD, rsR' in V1 (RV vol overload); Crochetage (primum)
CXRCardiomegaly, ↑ pulmonary vascular markingsCardiomegaly (RA, RV enlarge), ↑ pulmonary vascular markings
ComplicationsEisenmenger syndrome, IE, ARPulmonary HTN, paradoxical embolism, arrhythmias (AF)
Management HighlightsSpontaneous closure (muscular); Surgery if $Qp/Qs$ > 1.5-2:1Device/Surgery if $Qp/Qs$ > 1.5:1; Often asymptomatic

PDA & Coarctation - Duct & Constriction Dramas

Patent Ductus Arteriosus (PDA) and Coarctation of Aorta (CoA) represent significant acyanotic congenital heart diseases, one a persistent duct, the other a critical aortic narrowing.

FeaturePDA (Patent Ductus Arteriosus)Coarctation of Aorta (CoA)
Pathophys.Aorta-PA shunt (L→R)Aortic narrowing (juxtaductal)
Murmur📌 Continuous "machinery" (Gibson) L infraclavicularSystolic (L interscapular); possible ejection click
PulsesBounding; Wide pulse pressureRadio-femoral delay; BP: Upper > Lower limbs (> 20 mmHg)
CXRCardiomegaly, ↑ pulm. vascularity"3" sign; 📌 Rib notching (Roesler's sign, collaterals)
RxPreterm: Indomethacin/Ibuprofen; Device/Surgical closureNeonates: PGE1; Surgical/Balloon angioplasty
Coarctation of Aorta Anatomy

PDA Management Algorithm:

⭐ Indomethacin or Ibuprofen promotes PDA closure in preterms. Prostaglandin E1 (PGE1) keeps the ductus arteriosus open, vital in duct-dependent lesions like severe CoA.

Valvular Stenoses (AS & PS) - Outlet Obstruction Ops

FeatureAortic Stenosis (AS)Pulmonary Stenosis (PS)
TypesValvular, Subvalvular (membranous/muscular), SupravalvularValvular (most common), Subvalvular (infundibular), Supravalvular
MurmurEjection systolic @ RUSB, radiates to carotids; ↑squattingEjection systolic @ LUSB, radiates to back/axilla; ↑inspiration
Symptoms📌 SAD: Syncope, Angina, Dyspnea; CHF (infants)Often asymptomatic; Dyspnea, fatigue; RV failure (severe)
ECGLVH (strain pattern)RVH (strain pattern)
EchoThickened valve, ↓mobility, LVH; Post-stenotic aortic dilatationThickened valve, doming, RVH; Post-stenotic PA dilatation
Severity (Peak Gradient mmHg)Mild: <25; Mod: 25-49; Severe: ≥50Mild: <30; Mod: 30-60; Severe: >60
ManagementBalloon valvuloplasty (children), Valve replacement; PGE1 (critical AS)Balloon valvuloplasty (preferred), Surgical valvotomy

High‑Yield Points - ⚡ Biggest Takeaways

  • VSD: Most common CHD overall; presents with harsh holosystolic murmur at left lower sternal border.
  • ASD: Characterized by wide, fixed split S2; carries risk of paradoxical emboli in adults.
  • PDA: Features continuous machine-like murmur; indomethacin for closure, prostaglandins maintain patency.
  • Coarctation of Aorta: Shows BP discrepancy (↑upper, ↓lower limbs), weak femoral pulses, and rib notching.
  • Syndromic associations: Down syndrome (AVSDs, VSD), Turner syndrome (coarctation, bicuspid aortic valve).
  • All left-to-right shunts can eventually lead to pulmonary hypertension and Eisenmenger syndrome (cyanosis).

Practice Questions: Congenital Heart Diseases: Acyanotic

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Commonest congenital heart disease is:

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Flashcards: Congenital Heart Diseases: Acyanotic

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_____ is the commonest congenital heart disease

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_____ is the commonest congenital heart disease

Ventricular septal defect (VSD)

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