Fidji Simo announced on Thursday that she's stepping down from her executive role at OpenAI. JOEL SAGET / AFP Fidij Simo is stepping down from her executive role at OpenAI. Simo took medical leave in April to treat postural tachycardia syndrome, or POTS. POTS is a disorder that can cause heart palpitations, lightheadedness, and fainting. Fidji Simo is stepping down from her executive role at OpenAI. Simo, the company's applications CEO, said she is leaving her full-time role due to her chronic