Is a right heart catheterization indicated for a patient with ASD secundum and shortness of breath, confirmed by TEE with bubble study?

Right Heart Catheterization for ASD Secundum with Shortness of Breath

Diagnostic right heart catheterization is not routinely indicated for your patient with confirmed ASD secundum by TEE with bubble study, provided the noninvasive imaging adequately assessed pulmonary artery pressures, shunt magnitude (Qp:Qs), and right ventricular enlargement. 1

When Catheterization is NOT Needed

For most younger patients with straightforward ASD secundum where TEE has clearly demonstrated the defect morphology, right ventricular volume overload, adequate estimation of pulmonary pressures, and shunt magnitude, proceed directly to closure planning without diagnostic catheterization. 1 This represents a Class III recommendation (not indicated) from the ACC/AHA guidelines. 1

The key is that your TEE with bubble study has already confirmed:

• The defect is secundum type 2
• Defect size and morphology are clear 1
• Evidence of right ventricular volume overload can be assessed 1
• Shunt direction is established 2

When Catheterization IS Indicated

You must perform diagnostic right heart catheterization in specific high-risk scenarios: 1

Mandatory Indications:

• Elevated or uncertain pulmonary artery pressures - If noninvasive imaging suggests PA systolic pressure ≥50% of systemic pressure or pulmonary vascular resistance >1/3 systemic resistance, invasive hemodynamic assessment is required before closure decisions 2
• Age >40 years - Older adults frequently have acquired left ventricular diastolic dysfunction that can paradoxically worsen after ASD closure, making hemodynamic assessment critical 1
• Discrepant or inconclusive noninvasive data - When echo estimates of pressures or shunt magnitude are unreliable or conflicting 1
• Coronary artery disease risk factors - Consider coronary angiography during the same procedure in older patients 1
• Exercise-induced desaturation - Suggests possible pulmonary hypertension requiring invasive confirmation 1

Critical Hemodynamic Thresholds:

Closure is recommended (Class I) only when: 2

• PA systolic pressure <50% of systemic pressure
• Pulmonary vascular resistance <1/3 systemic resistance
• Qp:Qs ≥1.5:1
• Right atrial and/or RV enlargement present
• No cyanosis at rest or exercise

Closure should NOT be performed (Class III) when: 2

• PA systolic pressure >2/3 systemic
• Pulmonary vascular resistance >2/3 systemic
• Net right-to-left shunt present

Practical Algorithm for Your Patient

For a symptomatic patient with shortness of breath and confirmed ASD secundum by TEE: 1

1. Review the TEE findings carefully:

   • Does it clearly show RV volume overload? 1
   • What is the estimated PA pressure? 1
   • Is the patient >40 years old? 1
   • Any exercise-induced desaturation? 1

2. If PA pressure appears elevated on echo (>50% systemic) OR patient is >40 years OR echo data is unclear → Perform diagnostic right heart catheterization 1

3. If patient is young, echo shows clear RV enlargement, PA pressures appear normal (<50% systemic), and Qp:Qs ≥1.5 → Skip diagnostic catheterization and proceed to closure planning 1

Important Caveat About Procedural Catheterization

If you plan percutaneous device closure, cardiac catheterization will be performed at the time of the procedure itself for device deployment, balloon sizing, and hemodynamic confirmation. 1 This is standard practice and distinct from a separate diagnostic catheterization. 1 The procedure itself requires catheterization for device placement under fluoroscopic and echocardiographic guidance. 3, 4

Common Pitfalls to Avoid

Do not assume that "confirmed by TEE" automatically means catheterization is unnecessary. 1 The ACC explicitly states routine diagnostic catheterization carries a Class III recommendation (not indicated) only when noninvasive imaging is adequate. 1 The critical word is "adequate" - if there's any uncertainty about pulmonary pressures or the patient has risk factors (age >40, symptoms, elevated pressures), catheterization becomes necessary. 1

Adults over 40 with ASD often have acquired left ventricular diastolic dysfunction that can cause paradoxical worsening after closure. 1 This makes hemodynamic assessment particularly important in this age group, even if the ASD appears straightforward on imaging. 1