“I feel very well, both physically and mentally,” said Attila János Szikora, one of two young patients who recently underwent a groundbreaking cardiac procedure at the Department of Cardiac Surgery of the University of Szeged’s Albert Szent-Györgyi Clinical Center. With this operation, SZTE’s surgical team became the first in Europe – and the third worldwide – to implant an innovative vascular graft incorporating a biological heart valve.
What makes the procedure unique is that Dr. Gábor Bari and Dr. Sándor Varga, cardiac surgeons at the University of Szeged, implanted the vascular graft in an anatomical position different from the one originally intended by the manufacturer. This pioneering approach enabled the two young patients, János Hadabás and Attila János Szikora, to receive a biological heart valve expected to offer significantly greater durability, potentially reducing the need for future surgeries and improving their long-term quality of life.
Recovery off to a promising start
After pioneering procedures in the United States and Australia, the same groundbreaking cardiac surgery has now been successfully performed at the University of Szeged on János Hadabás and Attila János Szikora, both of whom were born with congenital heart defects and had undergone multiple heart surgeries before requiring this latest operation.
The early recovery of both patients has been remarkably encouraging. Just days after the procedure, both reported feeling well. János said he expects to be transferred soon to the Department of Cardiac Rehabilitation at Békés County Hospital in Gyula, marking what he hopes will be the next – and likely final – stage of his recovery. Attila, who had undergone surgery less than a week earlier, also reported excellent progress, saying he feels “very well, both physically and mentally.”
The surgeons who performed the groundbreaking procedures: Dr. Gábor Bari and Dr. Sándor Varga. Photo: István Sahin-Tóth
An innovation from the United States
The innovative procedure first came to the attention of Dr. Gábor Bari, senior assistant professor and head of the Department of Cardiac Surgery at the University of Szeged’s Albert Szent-Györgyi Clinical Center, during a visit to California in 2025, where he had the opportunity to learn about the latest developments from one of the world’s oldest heart valve manufacturers. Among the company’s newest innovations was a biological heart valve made from bovine pericardial tissue. As Dr. Bari explained, the valve undergoes a specialized preservation process designed to minimize the local inflammatory response and greatly reduce calcium buildup. As a result, it is expected to function effectively for a significantly longer period than conventional alternatives.
During his 2025 visit to California, Dr. Bari was also introduced to a newly developed vascular graft with an integrated biological heart valve. Previously, surgeons had to suture the biological valve and the synthetic vascular graft together during the operation. In this new design, the two components come preassembled, streamlining the procedure and reducing the complexity of the surgery.
“Compared with conventional solutions, this vascular graft offers far more than a modern biological heart valve,” explained Dr. Sándor Varga, Senior Assistant Professor at the Department of Cardiac Surgery of the University of Szeged’s Albert Szent-Györgyi Clinical Center. “The graft itself is designed to closely replicate the natural anatomy of the blood vessel, including the valve sinuses that help maintain normal physiological blood flow. While this feature is particularly important when the valve is implanted in the aorta, it may be even more beneficial on the right side of the heart, where blood pressure in the pulmonary circulation is much lower. Under these conditions, proper blood flow around the valve helps ‘wash’ its surfaces, which may further enhance its long-term durability.”
Dr. Sándor Varga. Photo: István Sahin-Tóth
A more durable solution
As Dr. Gábor Bari explained, one of the main limitations of biological heart valves treated with the advanced preservation technology is their high cost. For the indication originally intended by the manufacturer, their use has generally not been considered cost-effective, particularly because less expensive alternatives are already available. The University of Szeged team, however, recognized an opportunity to apply the technology in a way that could provide greater long-term benefits for a different group of patients.
“When we began discussing the best treatment options for patients who had undergone surgery for congenital heart defects in late childhood or early adulthood and whose previously implanted valves had reached the end of their lifespan, we wanted to offer them a more durable solution that would minimize the need for another valve replacement for many years,” Dr. Bari said. “It was Dr. Sándor Varga who proposed adapting the approach seen in California for these patients. For this patient group, we believe this solution could help postpone the need for another valve replacement for up to 20 years.”
Dr. Bari emphasized that every additional heart surgery significantly increases the risk of complications for patients with congenital heart disease. Because many of these patients undergo their first operation in childhood, they often require multiple procedures throughout their lives, with each repeat surgery involving reopening the chest carrying additional risks.
“We have a responsibility to reduce the number of these operations whenever possible,” Dr. Bari said. “The best way to achieve that is by using the most durable and advanced heart valves available.”
Dr. Gábor Bari. Photo: István Sahin-Tóth
From launch to approval in just 10 months
Using the new approach required special regulatory authorization because the vascular graft containing the biological heart valve was to be implanted for an indication other than the manufacturer’s original intended use. As Dr. Gábor Bari explained, the University of Szeged team ultimately received approval from Hungary’s National Center for Public Health and Pharmacy (NNGYK), which also enabled funding for the high-cost device. According to Dr. Bari, the authorization was granted on the basis of the team’s scientifically supported clinical rationale, reinforced by the successful outcome of the first procedure previously performed in the United States.
The specialists emphasized that the significance of this achievement extends well beyond the introduction of a new medical device. Equally important was the clinical innovation and interdisciplinary collaboration that made its application possible. Just 10 months after the manufacturer had introduced the valved vascular graft, the University of Szeged team completed the scientific and clinical groundwork required to obtain regulatory approval. They then became the first in Europe to use the device in a novel way – adapting it for a different clinical indication than the one originally intended by the manufacturer.
“The innovation lies in the fact that this device was originally developed for the complete replacement of the ascending aorta, the first section of the body’s main artery,” the specialists explained. “That was the indication for which it was clinically tested and approved. By contrast, the pulmonary artery and pulmonary valve are part of a much lower-pressure circulatory system, meaning the device was not originally intended for this application. However, our experience so far suggests that it performs exceptionally well in this setting as well.”
Dr. Sándor Varga and Dr. Gábor Bari. Photo: István Sahin-Tóth
A matter of pressure
As Dr. Sándor Varga explained, the aortic and pulmonary valves are remarkably similar in both their embryological development and anatomical structure. The key difference lies in the pressures they are designed to withstand: while the aortic valve functions under high pressure, the pulmonary valve operates in the heart’s much lower-pressure pulmonary circulation.
Both János and Attila underwent heart surgery in childhood, during which their own pulmonary valve was transferred to replace the diseased aortic valve, while the pulmonary valve was reconstructed using a pulmonary homograft – donor tissue transplanted from another person.
“Over time, pulmonary homografts can become calcified,” the specialists explained. “In János’s and Attila’s cases, however, the primary challenge was different. Their own pulmonary valves, which had been moved into the high-pressure position of the aortic valve, gradually became dilated over the years. Replacing the valve alone was therefore not sufficient. Because the ascending aorta had also gotten enlarged, both the valve and the affected section of the aorta had to be replaced.”
Patients Attila János Szikora and János Hadabás. Photo: István Sahin-Tóth
A new chapter for patients
János and Attila welcomed the opportunity to benefit from the innovative procedure. János had originally been scheduled for a different type of surgery, but on the day before the operation he learned that the team would be able to use a groundbreaking new device instead. As he recalled, the prospect of a shorter operation and a more durable heart valve made the decision straightforward.
“People born with congenital heart disease often have to undergo multiple heart surgeries throughout their lives. If innovations like this can reduce the number of those operations, that is an enormous benefit,” János said.
Attila shared the same perspective, adding that the opportunity to undergo the new procedure meant a great deal to him, particularly because he had already begun experiencing symptoms before the operation.
“I had started to notice signs that something wasn’t right – for example, my hands and feet would turn bluish. Since the operation, those symptoms have completely disappeared,” Attila said.
Dr. Gábor Bari expressed confidence in the long-term durability of the new device, noting that clinical studies indicate it can remain functional for up to 25 years even in high-pressure circulatory systems. In the lower-pressure pulmonary circulation, its lifespan may prove to be even longer, although this has yet to be confirmed through long-term clinical evidence.
Dr. Bari emphasized that the University of Szeged is committed to introducing innovative surgical techniques and advanced medical technologies into clinical practice as quickly as possible. He said the University’s strong institutional support allows promising developments to reach patients within a remarkably short time. He described the current case as an outstanding example of this approach and expressed confidence that it will pave the way for further surgical innovations in the years ahead.
Advancing cardiac surgery
Since his appointment as head of the Department of Cardiac Surgery in November 2024, Dr. Gábor Bari has identified innovation as one of his key priorities. As he explained, this commitment extends across several areas: from modernizing perioperative care – the entire process of preparing patients for surgery and supporting their recovery – to advancing surgical techniques and introducing cutting-edge medical technologies into everyday clinical practice.
Innovation in cardiac surgery also aligns closely with the vision of Prof. Dr. Tamás Szili-Török, Director of the University of Szeged’s Cardiology Center, whose strategic priorities include technological advancement, organizational development, and disease prevention. Under his leadership, the Center has established specialized departments, divisions, and multidisciplinary teams that together provide comprehensive expertise across the full spectrum of cardiovascular care.
Building on its long-standing strengths in cardiac surgery, interventional cardiology, electrophysiology, and angiology, the Cardiology Center has also launched dedicated programs in sports cardiology, cardio-oncology, and cardio-obstetrics, also providing specialized care for pregnant patients with complex cardiovascular conditions. The Center has further strengthened its multidisciplinary approach through the creation of a heart–brain team. The experts believe that this more integrated and transparent organizational model is a key driver of the continued advancement of cardiovascular care at the University of Szeged.
As Dr. Gábor Bari pointed out, cardiac surgery has long been associated with procedures requiring large chest incisions. Over the past few decades, however, minimally invasive techniques have transformed the field and become a major driving force behind surgical innovation worldwide. Reflecting this global trend, the University of Szeged has steadily expanded its use of minimally invasive endoscopic procedures, with the long-term goal of establishing a robotic cardiac surgery program.
Dr. Bari added that another key priority is to ensure that patients from the Department’s catchment area of approximately 1.2 million people have access to the highest-quality heart valve prostheses available. In line with this commitment, the Department has consistently selected prosthetic heart valves from the world’s leading manufacturers. This approach also reflects a clear international shift away from mechanical heart valves, which are made of carbon or synthetic materials, and toward biological valve prostheses. Thanks to continuous advances in valve technology, today’s biological prostheses can function for 15 to 20 years without significant deterioration and, in some cases, for as long as 25 years, according to current clinical studies.
As Dr. Gábor Bari explained, patients around the age of 50 would previously have been more likely to receive a mechanical heart valve. Although these valves are generally durable enough to last a lifetime, they require lifelong anticoagulant therapy, increasing the risk of complications such as bleeding and stroke. Recent advances, however, have transformed the field, with biological heart valves now achieving an expected lifespan of up to 25 years. As a result, these prostheses are increasingly being offered to younger patients, reflecting a major shift in international cardiac surgery.
Dr. Bari emphasized that the Department of Cardiac Surgery at the University of Szeged is committed to translating the latest advances into clinical practice, ensuring that patients benefit from the safest, most effective, and most durable treatment options available.
Original Hungarian article by Tímea Fülöp
Feature image: Dr. Gábor Bari, Attila János Szikora, János Hadabás, and Dr. Sándor Varga. Photo: István Sahin-Tóth
