II. Pathophysiology
- Occurs with conditions that impair left ventricular filling
III. Causes
-
Hypertrophic Cardiomyopathy
- Abnormally thickened Myocardium and abnormal mitral valve movement impair filling
- Subaortic Stenosis
- Bicuspid Aortic Valve stenosis
- Supravalvular Aortic Stenosis (SVAS)
- Rare condition, associated with Williams Syndrome (most common), as well as Familial Hypercholesterolemia
- Aortic Coarctation
- Hyperdynamic left ventricle
- Systolic anterior motion of the mitral valve (SAM)
- May complicate Mitral valve regurgitation or Mitral Valve Prolapse
- Mitral valve lodges in the left ventricular outflow tract resulting in mechanical obstruction
IV. Findings
V. Differential Diagnosis
VI. Imaging
VII. Management: Acute Emergent
- Early, emergent cardiology Consultation
- Stabilize Hypotension
- Intravenous Fluids (expand left ventricle and slows Heart Rate)
- Vasopressors
- Peripheral Vasoconstrictors (e.g. Vasopressin) are preferred
- Avoid inotropes (increase Heart Rate and contractility) that worsen obstruction
- Manage Tachydysrhythmias
- Other measures
- Avoid initial diuresis (decreases Preload)
VIII. Resources
- Left Ventricular Outflow Obstruction (StatPearls)
IX. References
- DeMeester and Swaminathan (2024) EM:Rap, 9/2/2024