Symptomatic orthostatic hypotension due to standing mid-left ventricular obstruction: a case report.

Background: Orthostatic hypotension (OH) is a common cardiovascular disorder typically associated with autonomic dysfunction. However, various other mechanisms can contribute to its occurrence. Case summary: An 88-year-old woman was referred to the cardiology unit due to recurrent syncope episodes while standing. Echocardiography revealed a normally contracting left ventricle with severe hypertrophy, a restrictive filling pattern, reduced stroke volume, and a decreased inferior vena cava diameter (4 mm/m²). In the standing position, she experienced syncope, and invasive blood pressure monitoring confirmed OH, alongside a normal increase in heart rate and evidence of mid-left ventricular obstruction (MVO) on echocardiogram. Discontinuation of diuretics and administration of fluids and beta-blockers effectively resolved the OH. Discussion: This case underscores the importance of considering mechanisms beyond autonomic dysfunction and volume depletion in the aetiology of OH in elderly patients. Notably, this is the first documented case of OH associated with MVO occurring in an upright posture, resulting in a significant decrease in cardiac output and subsequent syncope. Preventing volume depletion and using non-vasodilating beta-blockers may represent optimal therapeutic strategies in such cases.