What is the treatment for lipomatous interatrial septal hypertrophy?

Treatment for Lipomatous Interatrial Septal Hypertrophy

For symptomatic lipomatous interatrial septal hypertrophy causing obstruction or significant arrhythmias, surgical resection with reconstruction of the interatrial septum is the recommended treatment approach. 1, 2

Clinical Presentation and Diagnosis

• Lipomatous hypertrophy of the interatrial septum (LHIS) is characterized by abnormal accumulation of fatty tissue in the interatrial septum, often with a distinctive dumbbell configuration visible on imaging 1
• Patients may present with:
  • Atrial arrhythmias (most common symptomatic presentation) 3
  • Obstructive symptoms, particularly at the superior vena cava-right atrial junction 4, 5
  • Exertional dyspnea due to right atrial inflow obstruction 2
  • Syncope in severe cases of obstruction 5
• Diagnosis is typically made through echocardiography (particularly transesophageal), CT, or MRI, which show the characteristic fatty infiltration of the interatrial septum 1

Treatment Algorithm

1. Asymptomatic Patients

• Observation without intervention is appropriate for asymptomatic patients with incidentally discovered LHIS 1
• Regular follow-up with cardiac imaging to monitor for progression is recommended 1

2. Symptomatic Patients with Arrhythmias

• Initial management should focus on controlling arrhythmias with appropriate medications:
  • Beta-blockers or non-dihydropyridine calcium channel blockers (similar to management principles for other cardiac arrhythmias) 6
  • Antiarrhythmic medications may be considered based on the specific arrhythmia type 1

3. Symptomatic Patients with Obstruction

• For patients with significant symptoms due to obstruction (dyspnea, syncope) or intractable arrhythmias despite medical therapy, surgical intervention is indicated 4, 2
• Surgical approach includes:
  • Partial or complete resection of the lipomatous mass 4
  • Reconstruction of the interatrial septum, typically using a pericardial patch 4, 2
  • Concomitant procedures (e.g., coronary artery bypass) can be performed if other cardiac conditions are present 3, 4

Perioperative Considerations

• Preoperative assessment should include:

  • Comprehensive evaluation of the extent of obstruction via echocardiography 6
  • Assessment for concomitant cardiac conditions that may require intervention 3, 4

• Intraoperative management:

  • Maintain adequate preload to prevent hemodynamic instability 6
  • Avoid excessive vasodilation which may worsen any dynamic obstruction 6
  • Use transesophageal echocardiography to guide the extent of resection 2

• Postoperative care:

  • Monitor for conduction abnormalities and atrial arrhythmias 6
  • Continue antiarrhythmic medications if previously indicated 6

Special Considerations and Pitfalls

• LHIS may be confused with other cardiac masses, including malignancies, so proper histological confirmation is important 1
• Complete resection may not always be feasible or necessary; partial resection to relieve obstruction may be sufficient 4
• The fatty infiltration may recur after resection, so follow-up imaging is recommended 1
• In elderly or high-risk patients where surgery poses significant risk, a conservative approach with medical management of symptoms may be preferred 1

Outcomes

• Surgical resection typically provides good symptomatic relief in appropriately selected patients 2
• Mortality from the condition itself is rare but has been associated with sudden death in some cases, highlighting the importance of intervention for significantly symptomatic patients 1