Stanford Health Care recognized for mitral valve repair

Mia Cadua underwent surgery for mitral valve repair at Stanford Health Care, which was recently recognized for its excellent record with the procedure.

- By Tracie White

Mia Cadua underwent surgery to repair her mitral valve at Stanford Health Care.
Mia Cadua

Two years ago, when she was just 28, Mia Cadua discovered that she had a heart condition called mitral valve prolapse, which, if it worsened, could be fatal.

She had recently married, and the condition complicated her plans to have a baby.

“Of course I started crying,” said Cadua, who lives in Fairfield, in Northern California, with her husband. “They said, ‘Are you OK?’ and I said, ‘I’m just shocked right now.’ The doctors started monitoring me every six months.”

Last fall, things did get worse. Cadua started experiencing shortness of breath and fatigue. She went back to her doctors in Fairfield. Heart-imaging tests showed that her defective mitral valve was failing. Facing heart surgery, Cadua had some serious decisions to make. One of the most significant was whether to repair the valve or replace it.

After interviewing numerous cardiologists and surgeons, Cadua decided to have the valve repaired at Stanford Health Care, a designated a Mitral Valve Repair Reference Center — one of only eight in the country, and the only one in the West. The designation, made by the American Heart Association and Mitral Foundation, recognizes best practices in repairing mitral valves.

‘Superior clinical outcomes’

The designation was established to encourage more patients with severe mitral valve prolapse to get the valve repaired rather than replaced, according to a press release from the American Heart Association. Clinical guidelines, the release said, recommend repair over replacement whenever possible. But not all medical centers have surgeons capable of performing this advanced procedure.

It’s both art and engineering. You have to fix it so the flaps meet up exactly, perfectly.

Stanford Health Care, along with the other centers, demonstrated a record of “superior clinical outcomes in degenerative mitral valve repair,” the release said. 

“I would say that at least one-quarter of the thousands of cases across the country of patients with severely defective mitral valve prolapse, which could technically be repaired, are either having the valve replaced or not operated on at all,” said Joseph Woo, MD, professor and chair of cardiothoracic surgery at Stanford Medicine and the Norman E. Shumway Professor. “Now, with these new designations, patients can be referred to a center like ours with the expertise to do these complex repairs.”

Heart valves

The heart includes four valves that work together to keep the blood flowing in the same direction. With each heartbeat, these valves open and close their flaps, also known as leaflets, which work like doors opening to release blood and then closing to prevent the blood from flowing backward. The mitral valve has two flaps and the aortic valve has three.

Joseph Woo

Mitral valve prolapse is a condition in which the valve’s two flaps turn floppy and fail to close smoothly or evenly. The condition can be caused by genetic defects or wear and tear. Often, it is of minor concern and just needs to be monitored. But when symptoms such as shortness of breath or fatigue occur, it’s often because blood is leaking backward through the valve, as in Cadua’s case. To fix the problem, a surgeon can replace the valve with either a mechanical valve or one made of animal tissue — also called a biological valve. But both of these options have drawbacks. 

Patients implanted with mechanical valves need to take blood thinners for the rest of their lives, and blood thinners can cause birth defects. Patients implanted with biological valves can become pregnant safely but typically must undergo a second heart surgery within 10-20 years because the valves wear out. Even though Cadua planned to become pregnant, she rejected the option of a biological valve because she he did not want to have to face a second heart surgery.

In Cadua’s case, both of the mitral valve leaflets were diseased, making it a complex repair case, Woo said. The heart tissue needed to be rebuilt so the leaflets could close together, preventing blood regurgitation.

It’s sort of like French doors,” Woo said. “They meet each other at the doorjamb. Imagine the doorjamb missing and the doors flapping all over. You have to build a little bit of structure, some internal architecture. It’s both art and engineering. You have to fix it so the flaps meet up exactly, perfectly.”


Cadua said she was initially afraid of having heart surgery. She prayed for a good doctor and a good hospital. On Jan. 20, she was rolled into the operating room at Stanford Hospital. Woo performed the surgery, which lasted three hours.

“The surgeons told me before the operation that they would do their best to repair it, but there was a chance they might have to replace it,” she said.  When she woke up from the anesthesia following the surgery, she learned the news.

“They said, ‘You got what you wanted — you got the repair,’” she said. “I was so grateful. It was a miracle.” She and her husband plan to wait a year to make sure her heart is fully recovered before trying to conceive. 

“The doctors said to wait six months, but we want to be more safe,” she said. “Then we will try to have a baby together.”

About Stanford Medicine

Stanford Medicine is an integrated academic health system comprising the Stanford School of Medicine and adult and pediatric health care delivery systems. Together, they harness the full potential of biomedicine through collaborative research, education and clinical care for patients. For more information, please visit

2024 ISSUE 1

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