Heart surgery

Pioneers: Minimally Invasive Cardiac Surgery

Ken Mehrtens, 80, underwent open-heart surgery 21 years ago to repair a leaking mitral valve. When doctors determined last year that the same valve was leaking again, allowing blood to flow back into his heart, the last thing the Grafton resident wanted was another round of invasive surgery.

“I wasn’t looking forward to having my chest open again,” said the former heavy equipment operator, who suffered from shortness of breath and fatigue.

But treatment options have evolved over the past two decades, rendering his concerns moot. In October, Ken became the first person in Wisconsin to have a breakthrough procedure called LAMPOON, short for Laceration of the Anterior Mitral Leaflet to Prevent Outflow Obstruction. This procedure repaired her leaking mitral valve in a minimally invasive way.

The procedure was performed at Froedtert Hospital, the academic medical center of the Froedtert Health Network & the Medical College of Wisconsin, by Peter Mason, MD, MPH, interventional cardiologist and MCW faculty member, and Paul Pearson, MD, PhD, cardiothoracic surgeon and MCW faculty member.

“It’s a rare procedure,” Dr. Mason said. “The clinical situation doesn’t come up often, and you need a strong team with the experience, the will and the ability. The combination of expertise and experience of the Froedtert & MCW cardiovascular team makes these options possible.

Mitral valve leak complicates treatment

“For all patients, especially those considered to be at high risk for open heart surgery, we are focused on finding the least invasive treatment options,” Dr. Pearson said. “When we considered Ken’s age and the medical complexities, we knew he needed a minimally invasive technique.”

In addition to a leaky mitral valve, Ken suffers from a rare blood disorder called light chain amyloidosis. “His heart condition came to light during treatment for amyloidosis,” said Anita D’Souza, MD, MS, hematologist, oncologist, and MCW faculty member.

Chris Mueller, MD, cardiologist and MCW faculty member, diagnosed the valve leak after performing an echocardiogram at Froedtert & MCW Pleasant Valley Health Center in West Bend.

“It became clear that the mitral valve leak was more serious than previously thought,” Dr. Mueller said. “Even after Ken’s surgery in 2001, in which surgeons fitted a synthetic ring around his mitral valve to reinforce its structure, it remained moderately leaky.”

Prior to the LAMPOON procedure, Ken underwent chemotherapy from November 2019 to February 2020, followed by a stem cell transplant in June, aimed at better controlling amyloidosis.

“The treatment was successful with no detectable trace of the underlying disease,” Dr. D’Souza said.

Minimally Invasive Heart Valve Procedure

Dr. Mason and Dr. Pearson decided Ken’s best option was a valve-in-ring procedure, which involves using a catheter to place a new valve inside the synthetic annulus.

But Ken’s anatomy presented a challenge. The mitral valve has two leaflets, or gates, which open and close. Dr. Mason said Ken’s anterior leaflet was long enough for the placement of the new valve to block blood flow from the heart to the aorta.

The LAMPOON procedure is an elegant solution to the problem. He uses an electrified wire to cut the anterior tip of the leaflet into two parts.

“It flares out the flyer, so it looks like pants instead of a skirt,” Dr. Mason said. “The slit in the leaflet allows blood to exit the heart.”

During the procedure, a wire is inserted through a catheter into each leg. They are then shaped into a “V” and maneuvered to the end of the anterior mitral leaflet. The electrified “V” is gently moved from the tip of the leaflet to its base, cutting as it goes. The new valve was installed after the LAMPOON procedure.

Cardiovascular treatment options

Ken returned home a day after the procedure. “I woke up and felt great with no pain whatsoever,” he said. “I don’t think I could have received better care anywhere else. Everyone was so good to me – so friendly, happy and helpful.

Ken also said that while he was amazed the procedure could be done via catheters, he never felt apprehensive.

“If you don’t have many alternatives, you have to trust your doctors,” Ken said. “They were great.”

Ken’s treatment underscores the value of the cardiovascular team’s multidisciplinary approach to patient care.

“Our team has many different tools that we can use to tailor treatments to each patient,” Dr. Pearson said. “We also have people with different areas of expertise looking at the same issue, and those different perspectives allow for a safer patient experience and better outcomes.

“Doing the LAMPOON procedure was exciting. It’s always wonderful to be able to help people by offering them a minimally invasive procedure. And now we have another tool in our toolbox.

To learn more about the minimally invasive treatment options performed by our team of cardiovascular experts, visit froedtert.com/heart-care. Call 414-777-7700 for an appointment or a second opinion.