Episode 119: Left Ventricular Outflow Tract Obstruction (LVOTO)

Left Ventricular Outflow Tract Obstruction (LVOTO) is a critical but often under-recognized cause of worsening shock in ICU-boarded or critically ill ED patients.

LVOTO results from systolic anterior motion of the mitral valve causing outflow obstruction and mitral regurgitation, which worsens cardiac output. It is commonly precipitated by hyperdynamic states like sepsis, inotropes, or decreased preload.

Key clinical clues include persistent hypotension despite escalating vasopressors, new end-systolic murmur, and pulmonary edema refractory to diuretics. Diagnosis hinges on echocardiography showing narrowing of the LV outflow tract and a characteristic dagger-shaped Doppler profile.

Treatment involves a four-step approach: stopping inotropes and afterload reducers, cautious fluid administration to increase preload, using pure vasoconstrictors without beta-agonism like phenylephrine, and adding beta-blockers (e.g., esmolol) to reduce obstruction by prolonging LV filling time.

Early recognition and targeted management can dramatically improve outcomes in this complex hemodynamic emergency often missed in the ED.

• A 43-year-old man with mitral valve replacement develops LVOTO during septic shock in the ED while waiting for ICU.

• LVOTO results from systolic anterior motion of the mitral valve causing obstruction and mitral regurgitation.