(Vienna, 25 February 2026) In January 2026, eight lung transplant recipients and their companions from five countries, together with a team of doctors from MedUni Vienna, climbed Aconcagua (6,961 metres) in Argentina – the highest peak in America. During the expedition, they received medical care and were examined; the data collected is now being scientifically evaluated at MedUni Vienna. After returning to their home countries following this sporting and medical feat, the patients and doctors reported on their experiences at a press conference.
After Kilimanjaro in 2017 and Jebel Toubkal in 2019, Aconcagua in 2026 was already the third destination for high-altitude expeditions for lung transplant patients, which were initiated, organised and accompanied by lung specialist Peter Jaksch (Department of Thoracic Surgery). The main aim of these tours is to highlight the capabilities of people after organ transplants: "Lung transplant patients in particular are perceived by the public as permanently disabled. The expedition shows a different picture: carefully selected patients are physically resilient, adaptable and capable of performing even under extreme conditions – with scientific support and medical supervision," says Jaksch.
Of the eight lung transplant recipients from Austria, Switzerland, the USA, Croatia and Denmark, as well as a liver transplant recipient from Switzerland, the majority reached altitudes of over 5,500 metres together with their support team – all without the aid of additional oxygen. Helmut Steigersdorfer was the only patient to reach the summit of Aconcagua, accompanied by eight team members. The Upper Austrian had a donor lung implanted at University Hospital Vienna in 2002: "I wanted to show what is possible under controlled conditions with a lung transplanted 24 years ago, and thus give hope and confidence," says the 50-year-old about his motivation for participating. Reaching the summit was an "extraordinary experience for him – physically, mentally, but also personally". Steigersdorfer had no fear of medical complications: "With such a high concentration of competent doctors on the mountain, I didn't need any additional insurance."
A sporting challenge and scientific field laboratory
Medical monitoring of the participants and scientific support for the expedition was provided primarily by a team of doctors from MedUni Vienna. "The expedition was not only an extraordinary sporting challenge, but above all a scientific field laboratory under real conditions," says Jakob Mühlbacher (Department of General Surgery), who provided organisational and medical support for the expedition. The wide range of tests not only closely monitored the climbers' state of health, but also provided valuable data for research.
Regular blood gas analyses, for example, measured how well the body, and in particular the transplanted lung, functioned under oxygen deprivation at high altitude. In addition to other values, stool and saliva samples were also collected before and after the expedition, as well as immunological markers. AI-supported evaluation models were also used to analyse lung function and stress adaptation. Daily digital documentation was carried out using a structured system that recorded vital parameters, heart rate variability, oxygen saturation and standardised values as possible indicators of acute altitude sickness.
Summit success demonstrates the potential of modern transplant medicine
There were no medical emergencies during the Aconcagua expedition. "During the ascent, several participants – both transplant and non-transplant – experienced expected symptoms of acute altitude sickness, including headaches, sleep disturbances and nausea," reports Clemens Aigner, head of the Department of Thoracic Surgery, who also climbed to the summit as a member of the medical-scientific support team. The symptoms were easily controlled medically and did not lead to any life-threatening situations. Aigner: "The successful expedition symbolises the potential of modern transplant medicine. Projects like this highlight the achievements and quality of life that are possible after a successful lung transplant – and the role that the combination of surgical expertise and long-term aftercare plays in this."
"For me, the project stands for courage, team spirit and trust – in myself, in my body and in the people by my side," says Stefanie Krenmayer (31) from Upper Austria, who has been living with a transplanted lung since 2016. The fact that she made it to over 5,500 metres above sea level on Aconcagua fills her with "pride and gratitude". Stefanie Eigner from Vienna, born in 1984, who underwent a lung transplant at the University Hospital Vienna in 2017, expresses it similarly: "Joy and pride in my achievement and that of my fellow campaigners made this trip something very special. By taking part, I wanted not only to prove to myself what I can achieve, but also to inspire others to lead an active life and not to be afraid of a lung transplant."
With 100 to 110 lung transplants per year, the Department of Thoracic Surgery at MedUni Vienna and University Hospital Vienna is one of the ten leading centres in this field worldwide. The procedure is often the last life-saving treatment option for patients with severe lung disease. Despite major medical advances, long-term aftercare remains crucial, particularly with regard to immunosuppression, infection prophylaxis and possible rejection reactions. The high-altitude expeditions organised by MedUni Vienna and University Hospital Vienna with lung transplant patients provide valuable insights for research and further development in transplant medicine.