Subaortic Membrane Mimicking Hypertrophic Cardiomyopathy in the Setting of Mitral Valve Infective Endocarditis.

Infective endocarditis (IE) can present in a wide spectrum of systemic signs and symptoms. Here we report a case of a patient who presented with a headache. Upon further investigation, the patient was found to have mitral valve IE. This likely led to a subarachnoid hemorrhage secondary to a ruptured mycotic aneurysm. In this case report, we emphasize the importance of noticing early neurological signs of IE even when initial imaging is negative for aneurysmal formation. Further, this patient had a subaortic membrane (SAoM) mimicking the sonographic appearance of hypertrophic obstructive cardiomyopathy. Remarkably, SAoM is usually associated with aortic valvular pathology; however, this patient unusually presented with mitral valve involvement.