Cardiovascular · Topic 34 of 48

Adult Congenital Heart Disease

Cardiovascular · congenital heart disease

Adult Congenital Heart Disease

Unrepaired shunts can reverse into Eisenmenger syndrome; in the cyanotic adult, filter every IV line and protect systemic vascular resistance and volume.

Key numbers

Phlebotomy only for symptomatic hyperviscosityHct > 65%

01 · Look forASD: wide, fixed split S2

An atrial septal defect gives a soft midsystolic (pulmonary flow) murmur at the upper left sternal border with a widely split, fixed S2 and a right ventricular heave from right-sided volume overload.

02 · What it isEisenmenger: shunt reverses, cyanosis follows

Eisenmenger syndrome: a large unrepaired left-to-right shunt causes irreversible pulmonary vascular disease, so the shunt becomes right-to-left with cyanosis, clubbing and secondary erythrocytosis; the defect can no longer be closed.

03 · FirstAir filters on every IV line

Any right-to-left shunt lets venous air reach the brain: put air filters on all IV lines and place central access carefully in cyanotic or Eisenmenger patients.

Causes & risk factors

Why it happens

Cyanotic patients both bleed and clotCyanotic heart disease brings platelet and clotting-factor defects with hemoptysis and intracranial bleeding, yet also thrombosis and paradoxical embolism; anticoagulation is individualized because warfarin risks pulmonary hemorrhage.

Noncardiac surgery: highest risk in cyanotic patientsEisenmenger, other cyanotic lesions and Fontan circulation carry the highest noncardiac surgery risk (hypotension, desaturation, arrhythmia, bleeding); plan with an ACHD team and favor regional anesthesia when feasible.

Presentation

What you'll see

ASD ECG: rSR′ in V1, right-axis deviationA significant ASD shows right-axis deviation, right ventricular hypertrophy or an rSR′ (RV conduction delay) pattern in V1; chest x-ray shows a dilated right heart and prominent pulmonary artery.

VSD: harsh holosystolic murmur, lower left sternal borderA VSD gives a harsh holosystolic murmur at the lower left sternal border with a normally split S2 when small; the shunt volume-loads the left ventricle, and small restrictive VSDs do not cause Eisenmenger syndrome.

Do right now

In this order

First moves

Air filters on every IV line

→

Avoid hypotension, vasodilation and dehydration

→

Phlebotomy only for symptomatic hyperviscosityHct > 65%

Why each step

Air filters on every IV lineAny right-to-left shunt lets venous air reach the brain: put air filters on all IV lines and place central access carefully in cyanotic or Eisenmenger patients.

Avoid hypotension, vasodilation and dehydrationWith fixed pulmonary resistance, any fall in systemic vascular resistance (anesthetic induction, vasodilators) increases right-to-left shunting and hypoxemia; avoid volume depletion and support SVR with vasopressors.

Phlebotomy only for symptomatic hyperviscosityDo not phlebotomize compensated, asymptomatic erythrocytosis at any hematocrit; reserve cautious isovolumic phlebotomy (saline replacement) for hyperviscosity symptoms, or before surgery when hematocrit exceeds about 65%; replete iron deficiency.

Management

Orders

Close ASDs with right ventricular volume overloadASDs causing right ventricular volume overload are closed — by transcatheter device for most secundum defects with adequate rims; ostium primum and sinus venosus defects need surgery.

PFO-associated stroke at 18–60: close itFor patients 18–60 with an ischemic stroke attributed to a PFO, SCAI recommends transcatheter PFO closure plus antiplatelet therapy over antiplatelet therapy alone.

Eisenmenger: pulmonary vasodilatorsPulmonary vasodilators — endothelin antagonists (bosentan), PDE-5 inhibitors (sildenafil, tadalafil) and prostacyclins — improve exercise capacity and likely survival; heart–lung transplant is reserved for severe symptoms.

Endocarditis prophylaxis for Eisenmenger patientsGive endocarditis prophylaxis before bacteremia-prone procedures in Eisenmenger syndrome; after ASD repair it is needed only for the first 6 months or with a residual defect next to a patch.

Red flags & don'ts

Avoid harm

Unrepaired ASD: atrial arrhythmias and paradoxical emboli complicationAfter about age 20, an unrepaired ASD causes atrial flutter or fibrillation, exercise intolerance, right heart failure, pulmonary hypertension and paradoxical emboli (stroke).

Cyanosis complications: brain abscess, stroke, gout, gallstones complicationChronic cyanosis causes brain abscess and stroke (paradoxical emboli), gout from hyperuricemia, and gallstones from increased red-cell turnover.

ASD or VSD?

Commonly confused

Murmur	Soft midsystolic ejection murmur, upper left sternal border
S2	Wide, fixed split
Volume overload	Right atrium and right ventricle
Eisenmenger risk	Late — usually age 20–40 if large and unrepaired
Closure	Transcatheter device for most secundum defects

Teach & follow up

Patient education

Eisenmenger: avoid pregnancy, altitude, dehydrationTeach Eisenmenger patients to avoid pregnancy, volume depletion, isometric exercise, high altitude and smoking.

More detail

Reference

Show 7 reference facts

Pre-tricuspid shunts (ASD, partial anomalous pulmonary venous return) usually cause Eisenmenger symptoms at age 20–40; post-tricuspid shunts (VSD, PDA) can do so within the first years of life.

Clubbing and cyanosis of the feet but not the hands (differential cyanosis) point to Eisenmenger physiology through a patent ductus arteriosus.

Eisenmenger examination: central cyanosis, clubbing, RV heave, a loud single S2, and murmurs of tricuspid or pulmonary regurgitation; the original shunt murmur may be soft or absent.

Subpulmonary (outlet) VSDs are often associated with aortic leaflet prolapse into the defect, causing aortic regurgitation.

Fontan circulation is preload dependent: positive-pressure ventilation and high PEEP lower venous return and cardiac output, and acidosis raises pulmonary vascular resistance.

Treat hyperuricemia in cyanotic patients with allopurinol; supplemental oxygen may give some symptomatic benefit.

VSD closure is usually surgical (mortality < 2%; complications include residual shunt and complete heart block); transcatheter device closure is possible for some defects but rarely preferred.

Pearl

In Eisenmenger syndrome the pulmonary resistance is fixed — any fall in systemic resistance sends more blue blood to the body.

Sources · Merck Manual Professional — Atrial Septal Defect (ASD) · Merck Manual Professional — Ventricular Septal Defect (VSD) · Merck Manual Professional — Eisenmenger Syndrome · Perioperative Risk in Adults with Congenital Heart Disease Undergoing Non-Cardiac Surgery: Challenges and Tailored Strategies. J Clin Med 2025 · Kavinsky CJ et al. SCAI Guidelines for the Management of Patent Foramen Ovale. J Soc Cardiovasc Angiogr Interv 2022 · Starter sheet built from the verified AGACNP fact map (facts reviewed 2026-10-15).