What influence does sport have on heart failure?

 (Image: Pixabay CC0)
(Image: Pixabay CC0)

An estimated four million people in Germany suffer from heart failure, and around half of these patients have heart failure with preserved pumping function. What influence does endurance and strength training have on the progression of this often life-threatening disease? The world’s most comprehensive study to date, which was led by scientists from the German Heart Center at Charité Berlin, University Medicine Leipzig, University Medicine Rostock and TUM University Hospital Munich and published in the journal Nature Medicine, provides important insights into this question.

In heart failure, also known as cardiac insufficiency or cardiac insufficiency, the heart is no longer able to supply the body with sufficient blood and therefore oxygen and nutrients. Regardless of the cause, doctors distinguish between two forms of heart failure: if the heart muscle can no longer pump hard enough, this results in "heart failure with reduced ejection fraction" (HFrEF). In contrast, around half of all patients have heart failure with preserved ejection fraction, or HFpEF for short. In this case, the relative ejection capacity of the heart is still within the normal range, but the heart cannot relax properly between two heartbeats and therefore cannot absorb the blood well. HFpEF leads to similar symptoms and risks as HFrEF, but there are far fewer treatment options available for this form of heart failure.

Influence of exercise on the disease and quality of life

What influence does targeted physical training have on the course of the disease and the quality of life of patients? Dieser Frage ist ein Forschungsteam um Prof. Frank Edelmann (Oberarzt der Klinik für Kardiologie, Angiologie und Intensivmedizin am Campus Virchow-Klinikum des Deutschen Herzzentrums der Charité, DHZC, und für kardiovaskuläre Prävention), Prof. Rolf Wachter (Professor für Klinische und Interventionelle Kardiologie an der Universität Leipzig und Stellvertretender Klinikdirektor der Kardiologie am Universitätsklinikum Leipzig), Prof. Burkert Pieske (Head of the Heart Failure Division of the Department of Cardiology, Rostock University Hospital) and Martin Halle (Medical Director of Preventive Sports Medicine and Sports Cardiology at the TUM University Hospital in Munich).

The Exercise training in Diastolic Heart Failure (Ex-DHF) study, funded by the German Research Foundation (DFG), was conducted at eleven sites in Germany and Austria and included 322 patients with HFpEF who were randomly assigned to either a one-year structured training program or standard medical care. "In terms of the number of study participants and the observation period, this is the world’s most comprehensive study on this topic to date," says Frank Edelmann from Charité Berlin.

Structure of the training program

The training program consisted of a combination of endurance and strength training, in which the participants trained three times a week under supervision. At the beginning, the training consisted of 30 minutes of moderate cycling, which was gradually increased to 60 minutes over three months. After four weeks, strength training for the large muscle groups was also integrated. The patients trained for a total of one year.

The success of the training was primarily measured using the so-called "modified Packer score", which combines various parameters such as symptoms, exercise capacity, hospital stays and general well-being. The NYHA class and peak oxygen uptake (VO2) were also recorded. The NYHA class classifies patients according to the severity of their heart failure. Peak oxygen uptake (VO2) indicates how much oxygen the body can absorb during physical exertion.

The scientists recently published the results of the study in Nature Medicine, one of the world’s most important journals for medical research. In summary, no significant improvement in the modified Packer score as a combination of various health parameters was observed in most patients after one year of training. However, two of the five components improved significantly: peak oxygen uptake (VO2) and NYHA class, which indicates increased resilience and reduced symptoms.

Exercise as a valuable addition to treatment

"The results of our study show that physical training leads to an improvement in exercise capacity, but does not prevent patients from having to be hospitalized for heart failure, at least within the first year," concludes Prof. Rolf Wachter, cardiologist at Leipzig University Medicine. "Based on these results, we can recommend structured physical training to our patients with heart failure and preserved ejection fraction, as it is safe and improves performance and symptoms," adds Prof. Burkert Pieske, cardiologist at Rostock University Medical Center. Over the course of the study of one year, only 48 percent of the patients in the training group exercised at least twice a week; this group had the greatest benefit in the study. "The study shows us very clearly where the problem lies with training interventions: We need to do a better job of getting patients to maintain their training over a longer period of time," summarizes Prof. Martin Halle from the Technical University of Munich.

Original publication in Nature Medicine:

"Combined endurance and resistance exercise training in heart failure with preserved ejection fraction: a randomized controlled trial", DOI: https://doi.org/10.1038/s41591-0­24-03342-7