What is the treatment for sigmoid septum?

Treatment of Sigmoid Septum

Percutaneous transluminal septal myocardial ablation (PTSMA) is the recommended treatment for symptomatic sigmoid septum causing left ventricular outflow tract obstruction (LVOTO) when patients are refractory to medical therapy. 1

Understanding Sigmoid Septum

• Sigmoid septum is characterized by angulation between the basal interventricular septum and the ascending aorta 1
• While often considered clinically insignificant, it can cause left ventricular outflow tract obstruction, particularly during hypercontractile states 1
• Symptoms typically include exertional dyspnea that may be cryptogenic (without obvious cause) if not properly evaluated 1

Diagnostic Approach

• Echocardiography is the primary diagnostic tool, with special attention to dynamic assessment 1
• At rest, pressure gradients may be minimal with no systolic anterior motion (SAM) of the mitral valve 1
• Provocative maneuvers such as Valsalva are essential for diagnosis, as they can reveal significant increases in pressure gradients and demonstrate SAM 1

Treatment Algorithm

1. First-line: Medical therapy

   • Though not explicitly detailed in the evidence, standard medical management for LVOTO typically includes beta-blockers or calcium channel blockers 1

2. Second-line: Percutaneous transluminal septal myocardial ablation (PTSMA)

   • Indicated for patients with drug-refractory symptoms 1
   • Demonstrated effectiveness in significantly lowering pressure gradients 1
   • Can eliminate systolic anterior motion of the mitral valve 1
   • Results in dramatic symptom improvement, often by the following day 1

Clinical Pearls and Pitfalls

• Sigmoid septum may be misdiagnosed or overlooked if dynamic testing (Valsalva maneuver) is not performed during echocardiography 1
• PTSMA is a catheter-based therapy originally developed for hypertrophic obstructive cardiomyopathy but has shown effectiveness for sigmoid septum 1
• Rapid symptom improvement can be expected following successful PTSMA 1

Special Considerations

• The evidence specifically documents success in a 71-year-old female patient with long-standing exertional dyspnea 1
• PTSMA should be considered in patients with confirmed LVOTO due to sigmoid septum who remain symptomatic despite medical therapy 1