Current status, challenges, and future directions of heart transplantation in the United States and Western Europe

Current status, challenges, and future directions of heart transplantation in the United States and Western Europe

In nearly 60 years, heart transplantation has evolved from a daring vision to a mainstream surgical procedure. Since the first adult heart transplant in the United States was performed at Stanford Hospital in 1968, the field has made significant progress. However, challenges remain, including a shortage of donor organs and socioeconomic inequalities.

A recent study conducted by researchers at Stanford's Department of Cardiothoracic Surgery in collaboration with Germany's Helios Hospital examines the current status, challenges and future direction of adult heart transplantation in the two highest volume regions - the United States and Western Europe. Although both areas have achieved notable successes, they take different approaches to their transplant systems, shaped by the region's cultural and political attitudes.

As a leader in the field, Stanford has a decades-long history of pioneering and advancing heart transplantation. Our goal with the review was to provide clinicians around the world with insight into how other transplant systems work and to promote opportunities to learn from each other.”

Carol Chen, MD, lead author of the article and surgical director of adult heart transplantation at Stanford Health Care

Structures and guidelines in transplant organizations

Based on extensive literature research and studies over the last decades, Dr. Chen explains how transplant management systems in the United States have evolved differently than in many European countries. The donation frameworks “opt-in” and “opt-out” (presumed consent) stood out in particular.

“Despite having an opt-in organ donation system, the United States has one of the highest donation rates in the world,” said Dr. Chen. In the United States, both organ donation and transplant rates have increased steadily since 2015. Over the past decade, the overall rate of heart transplants has increased by more than 80%, reflecting changes in national allocation policies and more aggressive organ recovery practices. She found that European countries, in contrast, experienced minimal growth in transplant volumes over the same period.

In Europe, organ donation policies and practices vary widely, and many countries have implemented an organ donation opt-out system. International organizations such as Eurotransplant and Scandiatransplant play a crucial role in optimizing cross-border organ exchange and increasing the availability of donor organs. Despite this framework, many European countries continue to struggle with low donation rates due to limited resources, public awareness and ethical concerns surrounding opt-out systems.

“Compared to the single centralized organ allocation system used in the United States, the burden of the many layers of regional, national and international donation and allocation policies may play a role in fewer transplants being performed in Europe compared to the United States,” said Dr. Chen.

Addressing the donor shortage through innovation

With thousands of patients waiting for a heart transplant around the world, the demand for organs far exceeds the available supply. The authors highlight how each region has taken different approaches to this problem, including the use of mechanical circulatory support devices, marginal donors, and hearts from patients donated after circulatory death (DCD).

Recently, researchers have also explored the use of bioengineered hearts, mechanical devices, and xenotransplantation to address the shortage of donor organs. All have had varying degrees of success, but none have yet been able to replace a donated heart.

The technology is also transforming organ transport, helping to overcome the logistical challenges of time and distance. "By using new technologies, we can safely bridge greater distances between donor and recipient. This ability expands the donor pool and gives more of our patients at Stanford a chance at a new life," said Dr. William Hiesinger, associate professor of cardiothoracic surgery and division chief of heart and lung transplantation and mechanical circulatory support at Stanford.

In 2022, Stanford cardiothoracic surgeons developed and used a method to transplant a beating heart, supported by an organ perfusion system machine, into the recipient. Many transplant programs across the country have now adopted this technique. The use of these organ preservation systems has the potential to enable the global exchange of organs, thereby increasing the possibility of finding a suitable recipient.

“Addressing challenges such as donor shortages, geographic barriers and regulatory inconsistencies requires a concerted effort to ensure equitable access to life-saving therapies for all patients now and in the future,” said Dr. Chen.

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