What is the approach to physical exam of a patient with Tetralogy of Fallot?

Physical Examination of a Patient with Tetralogy of Fallot

The physical examination approach differs fundamentally between unoperated patients (rare in developed countries) and post-repair patients (the vast majority), with the latter requiring focused assessment for residual hemodynamic lesions that drive morbidity and mortality.

Unoperated/Palliated Tetralogy of Fallot

General Inspection

• Cyanosis and clubbing are typically present, with severity reflecting the degree of right ventricular outflow tract (RVOT) obstruction 1, 2
• Assess for features of genetic syndromes, particularly 22q11 deletion syndrome 1

Cardiovascular Examination

• Loud precordial systolic ejection murmur from RVOT obstruction, which may be mistaken for a small VSD in "pink tetralogy" patients with mild obstruction 1
• Continuous murmur over the thorax if abundant aortopulmonary collaterals are present 1
• Continuous murmur if a palliative shunt (e.g., Blalock-Taussig) is patent 1
• Diminished or absent brachial and radial pulses on the side of a classic Blalock-Taussig shunt 1

Post-Repair Tetralogy of Fallot (Most Common Presentation)

Cardiac Auscultation Findings

Right Ventricular Outflow Tract Assessment:

• Soft ejection systolic murmur in the pulmonary area is typical in well-repaired patients 1
• A louder systolic murmur suggests residual RVOT obstruction requiring further evaluation 1

Pulmonary Regurgitation (Most Common Residual Lesion):

• Low-pitched, delayed diastolic murmur in the pulmonary area indicates pulmonary regurgitation 1
• Absent P2 component of the second heart sound typically accompanies significant pulmonary regurgitation 1
• This is the most critical finding as pulmonary regurgitation leads to progressive RV dilation and dysfunction 1

Other Valvular Lesions:

• Pansystolic murmur suggests VSD patch leak 1
• Diastolic murmur at the aortic area indicates aortic regurgitation, which can be progressive 1
• Holosystolic murmur at the tricuspid area suggests tricuspid regurgitation secondary to RV dilation 1, 3

Signs of Hemodynamic Compromise

Indicators of RV Volume/Pressure Overload:

• Cardiomegaly on inspection/palpation should prompt search for residual hemodynamic lesions, most commonly pulmonary regurgitation 1
• RV heave suggests RV hypertrophy from residual RVOT obstruction or chronic volume overload 3
• Elevated jugular venous pressure may indicate RV dysfunction or significant tricuspid regurgitation 3

Signs of Decompensation:

• Peripheral edema, hepatomegaly, or ascites suggest right heart failure 3
• Cyanosis in a post-repair patient should prompt immediate evaluation for right-to-left shunting through a patent foramen ovale or residual ASD 1

Pulse and Blood Pressure Assessment

• Bounding pulses may suggest significant aortic regurgitation 1
• Asymmetric pulses indicate previous Blalock-Taussig shunt on the affected side 1
• Assess for right aortic arch (present in 25% of cases), which may be palpable in the right supraclavicular fossa 1

Critical Physical Exam Red Flags

Findings That Mandate Urgent Investigation:

• New or worsening cyanosis suggests right-to-left shunting through residual defects 1
• Signs of heart failure (edema, hepatomegaly, elevated JVP) indicate severe RV dysfunction from pulmonary regurgitation or residual obstruction 1, 3
• Irregular pulse suggests atrial arrhythmias (flutter/fibrillation), which indicate severe hemodynamic abnormalities 1
• Syncope or presyncope history raises concern for ventricular tachycardia, particularly with QRS >180ms on ECG 1, 3

Common Pitfalls to Avoid

• Do not dismiss a "soft" murmur as benign—even mild residual lesions can progress and cause RV dysfunction over time 1
• Absence of symptoms does not exclude significant pathology—many patients with severe pulmonary regurgitation and RV dilation remain asymptomatic until irreversible dysfunction occurs 1, 3
• Always assess for both pulmonary regurgitation AND residual RVOT obstruction—these can coexist and have different management implications 1
• Do not overlook aortic root examination—progressive aortic dilation and regurgitation are important late complications 1

Integration with Diagnostic Testing

The physical examination findings must be correlated with:

• Comprehensive echocardiography to quantify RV size/function, pulmonary regurgitation severity, and residual RVOT obstruction 1, 3
• ECG for QRS duration—QRS ≥180ms indicates increased risk of ventricular tachycardia and sudden cardiac death 1, 3
• Cardiac MRI as the reference standard for RV volume and systolic function assessment 1, 3