Ken Mehrtens, 80, had 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 backward 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 cracked open again,” said the former heavy equipment operator, who was experiencing shortness of breath and fatigue.
But treatment options have evolved in the past two decades, making his concerns moot. In October, Ken became the first person in Wisconsin to have a groundbreaking procedure called LAMPOON, short for Laceration of the Anterior Mitral Leaflet to Prevent Outflow Obstruction. This procedure allowed for his leaky mitral valve to be repaired in a minimally invasive way.
The procedure was done at Froedtert Hospital, the academic medical center of the Froedtert & the Medical College of Wisconsin health network, by Peter Mason, MD, MPH, an interventional cardiologist and MCW faculty member, and Paul Pearson, MD, PhD, cardiothoracic surgeon and MCW faculty member.
“It’s an uncommon 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 capabilities. The combination of expertise and experience available from the Froedtert & MCW cardiovascular team makes these options possible.”
Mitral Valve Leak Complicates Treatment
“For all patients, especially those considered high risk for open-heart surgery, we focus on finding the least invasive treatment options,” Dr. Pearson said. “When we considered Ken’s age and medical complexities, we knew he needed a minimally invasive technique.”
In addition to a leaking mitral valve, Ken has a rare blood disorder called light-chain amyloidosis. “His heart condition came to light during treatment of the amyloidosis,” said Anita D’Souza, MD, MS, hematologist, oncologist and MCW faculty member.
“It became clear the mitral valve leakage was more severe than previously thought,” Dr. Mueller said. “Even after Ken’s 2001 surgery, in which surgeons installed a synthetic ring around his mitral valve to strengthen its structure, it remained moderately leaky.”
Before the LAMPOON procedure, Ken had chemotherapy from November 2019 through February 2020, followed by a stem cell transplant in June, aimed at better controlling the 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 that Ken’s best option was a valve-in-ring procedure, which involves using a catheter to place a new valve inside the synthetic ring.
But Ken’s anatomy presented a challenge. The mitral valve has two leaflets, or gates, that open and close. Dr. Mason said Ken’s anterior leaflet was long enough that placement of the new valve would block blood flow from the heart into the aorta.
The LAMPOON procedure is an elegant solution to the problem. It uses an electrified wire to cut the anterior leaflet tip into two parts.
“It splays the leaflet, so it looks like a pair of pants instead of a skirt,” Dr. Mason said. “The split in the leaflet allows blood to exit the heart.”
During the procedure, a wire is inserted via catheter into each leg. They are then shaped into a “V” and maneuvered to the tip of the anterior mitral leaflet. The electrified “V” is gently moved from the tip of the leaflet toward its base, cutting as it goes. The new valve was installed after the LAMPOON procedure.
Cardiovascular Treatments Options
Ken went home a day after the procedure. “I woke up and felt great, with absolutely no pain,” he said. “I don’t think I could’ve 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 performed via catheters, he never felt apprehensive.
“If you don’t have many alternatives, you’ve got to trust your doctors,” Ken said. “They were terrific.”
Ken’s treatment underscores the value of the cardiovascular team’s multidisciplinary approach to patient care.
“Our team has a lot of different tools we can use to tailor treatments to individual patients,” Dr. Pearson said. “We also have people with different areas of expertise looking at the same problem, and those different perspectives make for a safer patient experience and better outcome.
“Doing the LAMPOON procedure was exciting. It’s always wonderful when you can help people by offering them a minimally invasive procedure. And now we have another tool in our toolbox.”