Left ventricular outflow tract obstruction in patients with Ebstein anomaly

Area of Science:

• Cardiology
• Cardiac Surgery
• Echocardiography

Background:

• Ebstein anomaly is a rare congenital heart defect affecting the tricuspid valve.
• Left ventricular outflow tract (LVOT) obstruction can complicate Ebstein anomaly, impacting patient management.
• Understanding the mechanisms of LVOT obstruction is crucial for effective treatment strategies.

Purpose of the Study:

• To investigate the clinical characteristics of patients with Ebstein anomaly and LVOT obstruction.
• To identify the mechanisms of LVOT obstruction using 2D echocardiography.
• To evaluate treatment outcomes for LVOT obstruction in this patient population.

Main Methods:

• Retrospective review of echocardiography and surgical databases from 1985-2022.
• Analysis of 14 patients diagnosed with Ebstein anomaly and LVOT obstruction.
• Echocardiographic assessment of obstruction mechanisms, including systolic anterior motion (SAM) and septal bowing.

Main Results:

• LVOT obstruction was identified in 14 Ebstein anomaly patients, with a mean age of 51.9 years; 78% were female.
• Dynamic LVOT obstruction with SAM was the most common mechanism, often associated with hypertrophic cardiomyopathy and leftward septal movement.
• Leftward septal bowing was a sole or contributing factor in 7 patients; 7 of 13 surgically treated patients underwent septal myectomy.

Conclusions:

• Multiple mechanisms, including SAM and septal bowing, cause LVOT obstruction in Ebstein anomaly.
• Septal myectomy during tricuspid valvuloplasty is a safe and effective procedure.
• Surgical intervention may reduce gradients and prevent the need for reintervention.