What is the management and treatment approach for dextrocardia (a condition where the heart is located in the right side of the chest)?

Management and Treatment of Dextrocardia

Dextrocardia itself requires no specific treatment when isolated, but management focuses on identifying and treating associated congenital cardiac anomalies, which are present in the vast majority of cases, and adapting diagnostic and surgical approaches to the altered cardiac anatomy. 1, 2

Initial Diagnostic Evaluation

The diagnostic workup must establish both the cardiac position and identify associated structural heart disease:

• Chest X-ray is essential to confirm dextrocardia and determine situs (solitus, inversus, or ambiguous), showing the characteristic straight left heart border due to leftward positioning of the ascending aorta 3
• ECG demonstrates inverted bundle branch patterns with early septal activation from right to left, producing deep Q waves in leads II, III, aVF, and V1-V3 that can be misdiagnosed as myocardial infarction 3
• Echocardiography with color Doppler is the primary diagnostic modality for detailed segmental cardiac analysis, identifying atrioventricular and ventriculoarterial connections and associated malformations 2, 4
• Cardiac MRI or ultrafast CT provides comprehensive anatomical assessment when echocardiography is insufficient, particularly for great vessel relationships and ventricular function 3, 4

Classification and Associated Anomalies

Understanding the situs determines the likelihood and type of associated cardiac defects:

Dextrocardia with Situs Inversus (Mirror-Image)

• Occurs in 39% of dextrocardia cases 2
• 73% have concordant atrioventricular connections, with the majority also having concordant ventriculoarterial connections 2
• Complex anomalies including transposition of great arteries (TGA), single ventricle, and common arterial trunk occur in approximately 62% of cases 4
• Only 29% have normal intracardiac anatomy, with some presenting with acquired conditions like rheumatic heart disease 2

Dextrocardia with Situs Solitus (Dextroversion)

• Occurs in 34% of dextrocardia cases 2
• Most commonly associated with congenitally corrected TGA (C-TGA) in 65% of cases, often combined with ventricular septal defect and pulmonary stenosis 4
• Only 7% have normal intracardiac anatomy 2
• Requires more aggressive surgical intervention due to higher complexity 2

Dextrocardia with Heterotaxy/Situs Ambiguous

• Accounts for 26% of cases (right isomerism 18%, left isomerism 8%) 2
• Right isomerism shows male predominance (2.2:1), cyanosis with decreased pulmonary blood flow in 87%, and high incidence of univentricular connections (39%) 2
• Left isomerism presents with increased pulmonary blood flow in 60% and inferior vena cava interruption in 60% 2

Surgical Management Principles

Technical Considerations

Surgical approach must be adapted to the altered anatomy, with displacement of the heart into the left pleural space allowing surgery in familiar anatomical orientation for the surgeon 5:

• Right atrial approach is typically required for intracardiac repairs in dextrocardia with situs solitus 5
• Standard surgical planes and techniques must be modified based on cardiac position 3
• Surgeons with specific training and expertise in congenital heart disease should perform all operations 3

Specific Surgical Interventions

For complex single-ventricle physiology (present in 58% of adult dextrocardia patients) 1:

• Fontan-type operations, including modified Fontan and total cavopulmonary connection, are the primary surgical options when indications are carefully evaluated 4
• Bilateral bidirectional cavopulmonary shunt demonstrates significantly better outcomes compared to unilateral anastomosis (odds ratio 27, P=0.005) 6
• The side of systemic venous pathway does not influence outcomes 6
• Survival to age 15 years is approximately 56% in single-ventricle patients with dextrocardia 6

For atrioventricular valve regurgitation (present in 61% of cases at presentation) 6:

• Aggressive surgical management of moderate or severe atrioventricular valve regurgitation improves long-term prognosis compared to conservative management 6
• Valve repair should be performed before systemic ventricular function deteriorates (before ejection fraction <45%) 3

For congenitally corrected TGA with dextrocardia 3:

• Anatomic repair with atrial and arterial switch or Rastelli repair when the left ventricle is functioning at systemic pressures 3
• Simple VSD closure when the defect is not favorable for LV-to-aorta baffling 3
• Systemic atrioventricular valve replacement for severe regurgitation before ventricular dysfunction develops 3

Diagnostic Imaging Challenges

Transesophageal echocardiography (TEE) is extremely challenging or impossible in dextrocardia, requiring non-standard imaging planes adjusted to individual patients 3:

• Standard TEE planes cannot be obtained in dextrocardia 3
• Transgastric planes are particularly useful for estimating pressure gradients across outflow tracts 3
• Alternative imaging with cardiac MRI or CT is often necessary for complete anatomical assessment 3

Long-Term Follow-Up

All patients with dextrocardia and associated congenital heart disease require lifelong follow-up in specialized adult congenital heart disease (ACHD) centers, typically annually 3:

• Serial echocardiography-Doppler studies and/or MRI every 1-2 years by staff trained in complex congenital heart disease 3
• Monitoring for systemic ventricular dysfunction, atrioventricular valve function, arrhythmias, and conduit function (if present) 3
• 24-hour Holter monitoring when progression of heart block is suspected 3
• Exercise testing to assess functional capacity 3

Arrhythmia Management

Arrhythmias occur frequently and require careful management 3:

• Electrophysiologic testing followed by ablation therapy is indicated for relevant arrhythmias 3
• 26% of adult patients require ablation procedures 1
• Antiarrhythmic therapy must be started cautiously due to risk of complete AV block and potential need for pacemaker implantation 3
• Sinus rhythm should be maintained when possible 3

Prognosis

Despite complex anatomy, patients with dextrocardia surviving to adulthood and managed in specialized ACHD centers demonstrate good medium-term survival 1:

• Mean follow-up of 7 years shows mortality of only 11% in adult patients 1
• 74% require surgical intervention during their lifetime 1
• Survival is significantly worse in single-ventricle patients (56% to age 15) compared to biventricular anatomy 6

Critical Pitfalls to Avoid

• Do not miss the diagnosis: Always consider dextrocardia when dextrocardia is present on chest X-ray, particularly with gastric bubble on the left and cardiac apex on the right 3
• Do not misinterpret ECG findings as myocardial infarction due to inverted septal activation patterns 3
• Do not delay surgical intervention for atrioventricular valve regurgitation until after ventricular dysfunction develops 3, 6
• Do not attempt TEE without recognizing its severe limitations in dextrocardia patients 3
• Do not perform complex surgical repairs without specialized congenital heart disease surgical expertise 3, 5