Remembering Dr. Jonathan M. Tobis

By Lauren Ingeno

For more than 40 years, Jonathan M. Tobis, MD, was an expert in matters of the heart.

The pioneering interventional cardiologist helped to define an emerging field of medicine, including performing the first digital left ventricular and coronary angiograms in the world, before joining the Division of Cardiology at the David Geffen School of Medicine in 1999.

“Everything that he worked on in his career is something that is making a major difference in taking care of patients throughout the world — that is the legacy he is leaving,” said Ravi Dave, MD, director of interventional cardiology at UCLA Health.

But it was Dr. Tobis’ own heart that his patients, colleagues and family will remember most.

“Regardless of what was happening in the cardiac catheterization lab, whether he was having a good or bad day, he would always have the biggest smile that would light up the room,” said Dr. Dave, who met Dr. Tobis at UCLA. “He was an incredibly kind human being.”

Dr. Tobis died at home in September after a two-year battle with kidney cancer. He was 77. He is survived by his wife, Nancy Greep, MD, two sons and two granddaughters.

Beyond his scientific and clinical contributions to the field, Dr. Tobis was also a beloved teacher and mentor, an adventurous outdoorsman and an athlete with a passion for travel.

Among his many hobbies, “he loved to backpack in the Sierra Nevada mountains,” remembers his son, Scott Tobis, MD. “He was an amateur astronomer and a voracious reader of history.” 

Dr. Tobis remained active well into his seventies. And he continued working until the very end of his life.

“I love being a doctor,” Dr. Tobis said in 2024, one year after receiving his cancer diagnosis. “I love taking care of patients, helping people. I would be bored if I didn’t do this.”

The son of a physician, Dr. Tobis was born and raised in Brooklyn, New York. He attended Amherst College, graduating in 1969 with honors in chemistry. He earned his medical degree from Albert Einstein College of Medicine in 1973 and came to Southern California in 1975 for residency at UC Irvine.

While at UC Irvine, his research ushered the cardiac catheterization laboratory into the digital age and made a lasting impact on the field of interventional cardiology.

At the time, an angiogram — a diagnostic test that uses X-rays to look at the heart’s blood vessels — required film that needed to be developed and viewed on a specialized machine, making it logistically complicated to share information between clinicians.

Dr. Tobis and his mentor, the late Walter Henry, MD, used animal models to investigate whether they could digitize this process and allow for real-time imaging and simpler information sharing.

In the early 1980s, Dr. Tobis performed the first digital left ventricular and coronary angiograms in the world. The innovation transformed the practice of angioplasty, a procedure that opens narrow or blocked arteries.

“Now you could do an angioplasty and get the results back immediately on the computer,” Dr. Tobis said in a 2024 interview.

Dr. Tobis went on to help develop the field of intravascular ultrasound imaging, which led to the safer placement of lifesaving stents to prevent heart attacks. In recognition of his seminal work in the field, he was named a prestigious Master Fellow of the Society of Cardiac Angiography and Interventions (MSCAI). 

“That particular procedure has really changed the way we practice,” Dr. Dave said. “It has been a game changer in our field and has resulted in significantly better outcomes for patients.”

When he was not in the hospital, Dr. Tobis loved to recharge in nature.

He summited Mt. Whitney — the tallest peak in the continental U.S. — twice. In 2017, he decided to combine his scientific and personal interests. Stationed for a week at 12,000 feet on the mountain, Dr. Tobis would chat with hikers and see if they were interested in enrolling in a clinical study about altitude sickness. 

Hikers who enrolled in the study were evaluated at a nearby hospital for patent foramen ovale (PFO), the most frequent congenital cardiac lesion. It has been linked to stroke, migraines and other conditions.

PFO was one of Dr. Tobis’ primary research focuses, and he treated 1,300 patients with PFO closures. The Mt. Whitney study led by Dr. Tobis found that hikers with acute mountain sickness were more likely to have a PFO. 

“It seemed just fascinating to me that here was this condition that we knew about anatomically, from medical school,” he said in an interview earlier this year, “but had no appreciation of the multiple manifestations and clinical syndromes that were associated with it.”

Dr. Tobis also loved traveling to Italy, and his most recent adventure was learning to speak Italian. Colleagues admired his ability to prioritize joy and leisure while juggling a demanding career. 

“He gave me the idea that it is okay to have a fun side — to enjoy a great moment with friends and talk about things unrelated to medicine,” Dr. Dave said. “He would leave on short trips, and I think that was his secret weapon. He would come back fully recharged and full of ideas.”

For several generations of junior-level faculty, Dr. Tobis was a teacher, a mentor and a living legend. 

“His passion for UCLA Cardiology, his patients, his mentees and other faculty was obvious,” said Priscilla Hsue, MD, chief of the Cardiology Division, who met Dr. Tobis when she joined the David Geffen School of Medicine in 2024. 

“Dr. Tobis was a legend in interventional cardiology. He was able to evolve with the times, and then to bring that knowledge to his patients and his mentees. That’s really amazing.”

And despite the long hours it took to achieve his many academic accomplishments, his wife and children were always his top priority, said his son, Dr. Scott Tobis. “He absolutely loved to spend time with his family.”

Dr. Tobis’ extensive body of research and decades of patient care was recognized at a symposium in 2024. The event, sponsored by UCLA Health and the David Geffen School of Medicine, also celebrated a large gift in his honor, which will create an endowed chair in his name upon Academic Senate approval.

“I’ve had a wonderful career and enjoyed what I did,” Dr. Tobis said ahead of the symposium. “I think I helped a lot of people. I have no regrets.” 

In lieu of flowers, Dr. Tobis and his family wish that donations be made to UCLA Health to continue his research projects.