No Need for Antithrombotics and Lower Risk of Reoperation… Expanding Treatment Options for Young Women Considering Pregnancy

Abandoned in Korea in the Early 2000s Due to Advances in Valve Replacements… Ross Procedure Returns After 20 Years Following Promising Long-Term Results Abroad

AMC Professor Ho Jin Kim “Will Establish a Stable Foundation for the Ross Procedure, Including Securing Homograft Tissue”

 

▲ Professor Ho Jin Kim of the Department of Thoracic & Cardiovascular Surgery at Asan Medical Center (right) is performing the Ross procedure.

 

 

Professor Ho Jin Kim of the Department of Thoracic & Cardiovascular Surgery at Asan Medical Center recently successfully performed the Ross procedure, replacing a damaged aortic valve with the patient’s own pulmonary valve. This marks the first time in nearly 20 years that the Ross procedure has been performed on an adult patient in Korea, offering new hope for those with heart disease.

 

The Ross procedure, first developed in 1967 by a British physician, Dr. Donald N. Ross, is a surgical method for treating aortic valve disease. By using the patient’s own pulmonary valve tissue, the procedure offers excellent biocompatibility and significantly reduces the burden of reoperation.

 

Traditionally, patients with aortic valve diseases have been treated by implanting mechanical valves or tissue valves derived from animals such as cows or pigs.

 

Mechanical valves can be used indefinitely, but they come with the drawback of requiring lifelong antithrombotic medication due to the risk of blood clots. Tissue valves, on the other hand, have a lifespan of only 10 to 15 years, posing a greater risk of reoperation, especially in younger patients. Transcatheter aortic valve implantation (TAVI), increasingly performed in recent years, also rely on tissue valves. As a result, they require reintervention after a certain period, making them more suitable for elderly patients.

 

▲ Professor Ho Jin Kim of the Department of Thoracic & Cardiovascular Surgery at Asan Medical Center (left) is performing the Ross procedure, carefully examining and removing the patient’s pulmonary valve.

 

The Ross procedure addresses these shortcomings by transplanting the patient’s pulmonary valve in place of the aortic valve and replacing the vacant pulmonary valve position with a pulmonary homograft. This approach eliminates the need for antithrombotic medication associated with the use of artificial valves and significantly lowers the risk of reoperation, making it particularly suitable for younger patients.

 

According to a paper published in the ‘Journal of the American College of Cardiology (JACC)’ in 2017, the 20-year long-term survival rate after the Ross procedure was 95%, significantly higher than the 68% survival rate in patients treated with mechanical valves. In addition to these findings, many recent studies have highlighted the superiority of the Ross procedure, and it is increasingly being performed at major hospitals across the United States and Europe.

 

Previously, young female patients with pregnancy concerns experienced inconvenience because they first used a tissue valve, which requires only 3-6 months of antithrombotic medication, necessitating reoperation 10-15 years later. With the introduction of the Ross procedure, they now have an alternative with a lower possibility of reoperation.

 

The Ross procedure involves simultaneous surgery on both the pulmonary and aortic valves, requiring highly skilled medical professionals and meticulous tissue management to ensure successful outcomes.

 

From the 1990s to the early 2000s, a few hospitals in Korea, including Asan Medical Center, performed Ross procedures on adult patients. However, the lack of advanced technology for obtaining and storing homograft tissue at the time raised concerns about infection risks. Combined with improvements in the performance of mechanical and tissue valves, the procedure was eventually discontinued.

 

Today, advancements in the safe storage of donated homograft tissue have addressed earlier concerns about infection risks. Additionally, with increasing life expectancy, there is growing demand for surgical methods that improve quality of life by reducing the need for reoperations and lifelong anticoagulant therapy.

 

Asan Medical Center has notably made continuous efforts to safely store and provide pulmonary homograft tissues donated by heart transplant recipients. Through the in-house tissue bank, Asan Medical Center follows stringent processing protocols to ensure the tissue’s safety and availability for patients in need.

 

The tissue processing procedure takes approximately 8 hours and involves antibiotic treatment and freezing to prepare for long-term storage. Microbial testing is conducted at each stage of the process, and if no issues are detected, the tissue can be stored safely for up to 10 years.

 

▲ Medical specialists after completing Korea's first Ross procedure in 20 years at Asan Medical Center in late August.

(From the left) Professors Joon Bum Kim and Ho Jin Kim Kim of the Department of Thoracic & Cardiovascular Surgery at Asan Medical Center, and Professor Christopher Malaisrie at Northwestern Memorial Hospital

 

The resumption of the Ross procedure at Asan Medical Center, after a 20-year pause in Korea, was made possible by the unwavering commitment of Professor Ho Jin Kim.

 

From 2021 to 2023, Professor Ho Jin Kim worked as a clinical fellow at Northwestern Memorial Hospital in Chicago, where he learned advanced surgical techniques directly from Professor Christopher Malaisrie, a global authority on the Ross procedure.

 

After returning to Korea in 2023, Professor Ho Jin Kim has taken a hands-on approach at Asan Medical Center, personally overseeing the collection and processing of intact pulmonary homograft tissue from heart transplant recipients to ensure its safe storage.

 

To maintain his surgical skills, Professor Ho Jin Kim conducted five Ross procedure simulations using pig hearts before performing his first surgery. These thorough preparations, combined with the support of Professor Malaisrie, who traveled to South Korea to attend a conference, made the first surgery successful in late August of this year. Two months after the surgery, the patient remains in healthy condition, free from complications or side effects.

 

While the Ross procedure has shown excellent results in the U.S. and Europe, securing pulmonary homograft tissue remains a critical challenge for its successful implementation in South Korea.

 

In South Korea, the acquisition of pulmonary homograft tissue mainly relies on valve donations from heart transplantation recipients. However, the limited number of heart transplantation and the stringent criteria for selecting suitable donor hearts make the process of obtaining and safely storing the tissue challenging.

 

Furthermore, donated pulmonary homograft tissue must undergo complex procedures such as washing and antibiotic treatment to minimize immune rejection and ensure safe storage. If any infection is detected during this process, the homograft tissue must be discarded.

 

In the United States, donated pulmonary homograft tissue is processed into products that hospitals can use for Ross procedures. However, this system has not been introduced in South Korea due to the lack of import procedures, as these products are expensive and classified as human tissue.

 

Previously, the Korea Public Tissue Bank used to store pulmonary homograft tissues, but production has ceased due to low demand. Given the lack of awareness and donation of human tissues and the complexity of acquiring and processing tissues, the availability and storage of pulmonary homograft tissues are expected to be pivotal factors in disseminating and expanding Ross procedure in South Korea.

 

Professor Ho Jin Kim stated, "With the reintroduction of the Ross procedure, young patients with aortic valve disease now have the opportunity to significantly improve their quality of life over the long term."

 

"We will continue to focus on establishing a stable foundation for performing the Ross procedure, including securing pulmonary homograft tissues, to ensure that we can offer the best treatment options to as many patients as possible."