He left medicine to build an AI tool – now, it’s worth $460 million

In 2017, Thomas Kelly graduated from medical school and finally became a doctor — a career he had dreamt about as a kid and spent years working towards. But once he started practicing, Kelly realized that the job was different from what he’d imagined.

“My time as a doctor [was] very constrained. I only get 10 minutes for the patient,” he told CNBC Make It. “I was finding I had, you know, 100 patients to see in a day, and [was] always in a rush and always coordinating 700 tests and a million tasks.”

“In a perfect world … I would spend as much time with [patients] as they need … I would understand their family, I would remember them deeply, and then I would check in on them regularly,” he said. However, the reality is that, like many other clinicians, he faced “incredible burnout” working in the field.

Inspired to tackle this problem, Kelly created an AI tool that helps transcribe medical visits, generates clinical notes and more, with the goal of lessening the load on doctors and clinicians.

Now, the 33-year-old is the co-founder and CEO of Heidi, an AI medical scribe. The company announced its $65 million Series B round in October, valuing the company at $465 million.

Growing up in Melbourne, Australia, Kelly was inspired by his primary care doctor to pursue medicine.

“I just loved my primary care doctor … He was like, the pinnacle of using your intelligence and knowledge for good,” said Kelly. “He always had an amazing plan. He was very warm, great bedside manner, but also, just incredibly sharp and intelligent always.”

That experience stayed with him. During university, he explored other interests such as math and computer science before ultimately deciding to go into medicine. In 2013, he enrolled into the University of Melbourne where he began medical school.

While studying medicine, Kelly also started a side hustle where he posted educational videos on YouTube and tutored students interested in getting into medicine.

To his surprise, the videos began to attract many students, more than he could handle at the time, and what started as a hobby steadily grew into a small business. To better manage his time during his tutoring business, Kelly began experimenting with building out artificial intelligence tools.

“The first AI product I ever tried to build was an interview tutor that people could practice with,” said Kelly. This tool, called “Oscar” allowed students to practice conversations with a medical interviewer, and by 2020, about 20,000 students were using it, he added.

“That was the seed that grew into Heidi,” he said.

As Oscar improved, Kelly began to notice its broader potential. “There was no [single] lightbulb moment,” Kelly said, however, he realized that if an AI tool could understand a conversation between a student and a medical examiner, it could do the same for a patient and a doctor.

“You could then create clinical notes. You could do differential diagnosis, potentially. You could complete tasks,” he said. “That is the root [of] medicine. It’s a very advanced, very technical, deep, complicated conversation, but it’s still a conversation.”

By 2021, Kelly was faced with a big decision: go all-in on his medical career and begin vascular surgery training or take a career break and try to build out his AI tool to help serve not just medical students but also clinicians and doctors.

“I took the leap,” said Kelly. “[I thought] I’ll regret it forever if I don’t take this chance. How many surgical trainees are good enough in math and have had business experience and can build this product? I think not many.”

“Maybe it was hubris, but I thought if anyone can start this company, it would be me, and let’s try and see what happens,” he said.

So in 2021, Kelly officially left his medical career behind and went all-in on building Heidi. Today, the tool assists in helping doctors offload some administrative tasks such as creating documentation, clinical notes and more.

Heidi has grown into a strong business and has attracted nearly $100 million in funding.

“At some point I just [did the] introspection … if you’re sitting in an aged care home and your family’s around you, what are the things you’re going to regret? And for me, it was, I definitely would have regretted not having tried,” said Kelly.

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