Medical shock waves: New perspectives and treatment options
Mechanotransduction as the basis for a wide range of medical shock wave applications
Shock waves are increasingly being used in various medical specialties. The shock wave is a form of mechanical energy that can penetrate the body through the skin without damaging the body’s surface and that acts specifically at certain depths of the organism. In medicine, shock waves are generated using electrohydraulic, piezoelectric or electromagnetic methods and the underlying principle of action ‘mechanotransduction‘ is becoming increasingly important as its mechanisms are now widely researched. Put simply, mechanotransduction describes a process in which mechanical stimuli are converted into biochemical signals, leading to cellular reactions.
One example of this is Transcranial Pulse Stimulation (TPS), which works with low-energy shock wave pulses. In neurology and psychiatry, TPS shockwave therapy is used for Alzheimer’s dementia and has been extensively researched internationally in relation to other neurodegenerative and neurophysiological diseases. In cardiology, however, a highly regarded recent study by the University of Innsbruck shows how shock waves can improve heart function by reactivating inactive heart muscle cells thanks to these principles of action. The study, published on June 20, 2024 in the “European Heart Journal”, is considered groundbreaking by experts and is currently attracting international attention. This is because it once again shows the possibilities that shock waves can offer in medicine.
Shock waves enable progress in the treatment of ischemic cardiomyopathy
For many years, a large team at the Medical University of Innsbruck has been researching a method for treating ischemic cardiomyopathy and has shown great perseverance in the process. The approximately 1.4 million people affected worldwide, on average 68 years old, suffer from shortness of breath and reduced physical performance.
After one or more heart attacks, heart muscle cells die off, leaving behind scars and leading to so-called ‘hibernating myocardium’. Hibernating myocardium refers to a condition in which heart muscle cells fall into a resting mode after a heart attack. Although these cells remain alive, they cease their activity and fall into a kind of hibernation. This leads to a chronic undersupply of blood to the affected heart muscle tissue. The bypass operations that are then performed can only maintain the remaining heart function, but not improve it.
New option in heart therapy: shock waves reactivate heart muscle cells
The scientists in Innsbruck have succeeded in reactivating heart muscle cells using shock wave therapy as a supplement to bypass surgery and sustainably improving the heart’s pumping capacity. “We know that every improvement of five percentage points significantly reduces hospital readmissions and increases life expectancy. Our method has shown an improvement of almost twelve percentage points. That is spectacular”, reports project leader Johannes Holfeld.
The treatment showed impressive results in the CAST-HF study with 65 patients. One group was treated with bypass surgery alone, while the second group also received shock wave therapy. Due to the remarkable success in the second group, the ethics committee gave its approval earlier than expected to enable all patients to receive shock wave treatment quickly.
Long-term results of the first patients treated with shock waves four years ago are now available: “The effects were clearer than expected and we were able to demonstrate significant improvements in the heart muscle at an early stage,” says Holfeld. The long-term results show that the effect remains stable and the heart recovers sustainably. “The heart recovers and then stays fit”, confirms clinic director Michael Grimm.
Shock waves are sound pressure waves that shear vesicles from the cell surface. These vesicles contain substances that activate the Toll-like receptor-3 (TLR-3), a receptor of the innate immune system. “We were able to prove that this receptor triggers effects that lead to connective tissue cells transforming into vascular wall cells and forming new blood vessels. As a result, new blood vessels sprout in the chronically undersupplied heart muscle, which actively contributes to the heart’s pumping capacity again”, Holfeld explains the mechanism. He and his team estimate that more than a third of all patients with heart failure, especially those with severely restricted pumping capacity, will benefit from shock wave treatment in the future.
Shock waves: Increasingly broad range of applications in medicine
Shock waves have become established in medicine in various specialist areas. This began with lithotripsy in the 1980s, in which kidney stones are broken up using shock waves. The procedure has been used millions of times to date. In orthopaedics, shock waves are used to treat tendon and muscle injuries and bone healing disorders, while dermatology uses shock waves to improve skin structure and treat cellulite and scars. These versatile applications show the broad potential of shock waves in medical therapy.
The fact that, after decades of research, shock waves are now also providing new treatment options in neurology and psychiatry with Transcranial Pulse Stimulation (TPS) and in cardiology, and that the effectiveness and functionality of shock waves is increasingly being proven in clinical studies, gives millions of patients new opportunities to lead a better life despite their illnesses.
Sources:
Johannes Holfeld et al, Cardiac shockwave therapy in addition to coronary bypass surgery improves myocardial function in ischaemic heart failure: the CAST-HF trial, European Heart Journal, 2024;, ehae341, https://doi.org/10.1093/eurheartj/ehae341
