Breaking News
September 25, 2018 - Gene therapy approach could help treat mitochondrial diseases
September 25, 2018 - Few Yogurt Products Qualify As Low-Sugar
September 25, 2018 - Eye disease can cause blindness, and it’s on the rise
September 25, 2018 - Pawnshop density linked to gun-related suicides, Stanford study finds
September 25, 2018 - Pioneering procedure for common prostate condition offered by The London Clinic
September 25, 2018 - Number of people with respiratory diseases likely to increase if UK air pollution remains unchecked
September 25, 2018 - FARXIGA receives positive results in Phase III DECLARE-TIMI 58 cardiovascular outcomes trial
September 25, 2018 - New program to reduce harmful stress effectively improves mood in cancer patients
September 24, 2018 - Florence’s Lingering Threat: Mold – Drugs.com MedNews
September 24, 2018 - For professional baseball players, faster hand-eye coordination linked to batting performance
September 24, 2018 - Bill for later school start times is defeated, but Stanford sleep specialist isn’t
September 24, 2018 - For Heart Failure Patients, Mitral Valve Procedure Improved Outcomes
September 24, 2018 - Successful recovery from addiction means more than achieving abstinence
September 24, 2018 - New nanoplatform technology may reverse drug-resistance in renal cell carcinoma
September 24, 2018 - October 1918 marks the centenary of Spanish Flu that claimed more lives than World War I
September 24, 2018 - LGBT community reports more number of poor mental health days than general population
September 24, 2018 - New research suggests power of zebrafish as tool for cancer drug discovery
September 24, 2018 - New study finds height as possible risk factor for developing varicose veins
September 24, 2018 - Researchers compare weight loss results of online and in-person diabetes prevention program
September 24, 2018 - New HER2 PET Study Uses Affibody’s ABY-025 Tracer to Individualize Breast Cancer Treatment
September 24, 2018 - Drug combination offers more effective care for patients suffering miscarriage
September 24, 2018 - Tallness linked to varicose veins, Stanford study says
September 24, 2018 - For Heart Failure Patients, Mitral Valve Procedure Improved Outcomes
September 24, 2018 - Ecstasy drug makes octopuses more social
September 24, 2018 - Immediate compression therapy could cut risk of complications after deep-vein thrombosis
September 24, 2018 - Transcatheter mitral valve repair reduces mortality for patients with mitral regurgitation
September 24, 2018 - First intracranial aneurysm patients treated with BRAVO Flow Diverter after CE mark approval
September 24, 2018 - ‘Physicians of the mouth’? Dentists absorb the medical billing drill
September 24, 2018 - People more likely to believe those with confident tone of voice than with accent
September 24, 2018 - Harmony Biosciences Presents 5-Year Data On Pitolisant At International Narcolepsy Symposium
September 24, 2018 - Blood test may identify gestational diabetes risk in first trimester
September 24, 2018 - Height may be risk factor for varicose veins | News Center
September 24, 2018 - King’s commemorates opening of new NMR facility with one-day symposium
September 24, 2018 - Eisai receives approval for partial label change of DC Bead device for transcatheter arterial embolization
September 24, 2018 - High-resolution genomic map gives scientists unprecedented view of brain development
September 24, 2018 - Researchers find impact of neurobehavioral symptoms on employment in adults with TBI
September 24, 2018 - Alexion announces positive results from Phase 3 PREVENT study of Soliris in patients with NMOSD
September 24, 2018 - First evaluation of benefits, harms of Alzheimer’s screening for family members of older adults
September 24, 2018 - Ancora Heart announces positive data of study evaluating AccuCinch Ventricular Repair System
September 24, 2018 - Children of mothers using cannabis may start using it at an earlier age, finds study
September 24, 2018 - Gilead Sciences plans to launch authorized generic versions of Epclusa and Harvoni in the US
September 24, 2018 - Most patients who underwent transcatheter valve replacement experience prosthesis-patient mismatch
September 24, 2018 - Lumos acquires license for LUM-201 drug that promotes secretion of growth hormone
September 24, 2018 - New study provides basis for Air Canada to change its facial hair policy for aircrew
September 24, 2018 - Infant walkers lead to thousands of emergency visits for babies
September 24, 2018 - Genes predicting person’s height may provide clues about causes of varicose veins
September 24, 2018 - EPA Plan Will Maintain Carbon Emissions From Power Plants
September 24, 2018 - Characterizing pig hippocampus could improve translational neuroscience
September 24, 2018 - Element3 Health reports social and mental engagement play key role in overall health
September 24, 2018 - Paralympic medalists support Fight for Sight’s unique virtual event
September 24, 2018 - ADCETRIS drug receives approval in Japan as frontline treatment option for Hodgkin lymphoma
September 24, 2018 - Public awareness of urological conditions found to be alarmingly low across Europe
September 24, 2018 - Fitter Folks Suffer Milder Strokes: Study
September 24, 2018 - Novel botulinum toxin compound relieves chronic pain
September 24, 2018 - CHMP recommends approval of Gilenya for treatment of multiple sclerosis in children, adolescents
September 24, 2018 - National Friendly’s private medical insurance is a hit with women living in the South East
September 24, 2018 - Academics receive prestigious awards for achievements in blood pressure research
September 24, 2018 - Obese pregnant women can restrict weight gain safely with proper nutrition guidance
September 24, 2018 - CHMP adopts positive opinion of Takeda’s ALUNBRIG for treatment of ALK+ non-small cell lung cancer
September 24, 2018 - China NMPA approves LENVIMA for treatment of unresectable hepatocellular carcinoma
September 24, 2018 - A new approach for finding Alzheimer’s treatments
September 24, 2018 - USC research uncovers previously unknown genetic risk factor for dementia
September 24, 2018 - Study examining mental health among students finds significant disparities in treatment across race
September 24, 2018 - Breakthrough discovery paves way for future test to identify drowsy drivers
September 24, 2018 - Transcatheter mitral-valve repair in patients with heart failure
September 24, 2018 - Study opens new avenues for treatment of Laing distal myopathy
September 24, 2018 - Stroke Facts | cdc.gov
September 24, 2018 - Sarcolipin tricks muscle cells into using more energy, burning fat
September 24, 2018 - Enrollment in opioid controlled substance agreement reduces primary care visits
September 24, 2018 - UTA researchers patent new smart seat cushion technology that helps prevent painful ulcers
September 24, 2018 - Second HPV-Related Primary Cancers Common in Survivors
September 24, 2018 - How a virus destabilizes the genome
September 24, 2018 - Old letters provide insight into Spanish flu pandemic horror
September 23, 2018 - Smart textile-based soft robotic exosuit helps wearers save energy and traverse difficult terrain
September 23, 2018 - New research hub to drive radical change in development and manufacturing of vaccines
September 23, 2018 - AHA: For Hispanics, Neighborhood May Be Key Factor in Heart Disease Risk
September 23, 2018 - Excessive airway nerves tied to more severe asthma symptoms, study finds
September 23, 2018 - Study highlights need to remain vigilant in maintaining key infection control processes
September 23, 2018 - Novel therapeutic strategy for blood vessel related disorders, such as cancer and retinopathy
September 23, 2018 - New naturally occurring antibiotic found effective against Mycobacterium tuberculosis
Heart researchers develop a new, promising imaging technique for cardiac arrhythmias

Heart researchers develop a new, promising imaging technique for cardiac arrhythmias

image_pdfDownload PDFimage_print
Maelstroms in the heart
From ultrasound images (left), Max Planck researchers have reconstructed how the heart muscle contracts vortex-like (centre) in cardiac arrhythmia. This also allows the researchers to locate the filaments (right) that form the centre of the vortices. It is hoped that these insights will provide the basis for developing improved treatment methods. Credit: MPI for Dynamics and Self-Organization

Every five minutes in Germany alone, a person dies of sudden cardiac arrest or fibrillation, the most common cause of death worldwide. This is partly due to the fact that doctors still do not fully understand exactly what goes on in the heart during the occurrence. Until now, it was impossible to visualize dynamic processes in the fibrillating heart muscle, or myocardium. In today’s publication in Nature, an international team of researchers headed by Jan Christoph and Stefan Luther of the Max Planck Institute for Dynamics and Self-Organization and Gerd Hasenfuß of the Heart Center at the University Medical Center Göttingen show for the first time how vortex-like, rotating contractions that underlie life-threatening ventricular fibrillation can be observed inside the heart with the help of a new imaging technique, which can be used with existing ultrasound equipment. In the future, this newly developed imaging technique may help medical doctors to image and thus identify heart rhythm disorders, helping them to better understand cardiac disease and further develop new, more effective methods for treatment.

When the heart muscle no longer contracts in a coordinated manner, but simply flutters or twitches – a condition referred to medically as “fibrillation” – it is a highly life-threatening situation. If the ventricles, the main chambers of the heart, twitch in this disorderly way, there is just one opportunity for medical intervention: the heart must be defibrillated within a few minutes with a strong electrical shock, which is very painful and can damage the heart’s tissue. Fibrillation of the atria, on the other hand, is not directly life-threatening; however, if left untreated it can have dire consequences. For over 100 years, researchers have sought to understand the mechanisms behind fibrillation so as to improve treatment options. “The key to a better understanding of fibrillation lies in a new, high-resolution imaging technique that allows processes inside the heart muscle to be observed,” says Stefan Luther, Leader of the Biomedical Physics Research Group at the Max Planck Institute for Dynamics and Self-Organization and Professor at University Medical Center Göttingen.

Diagnostic breakthrough

“The mechanical movements of the myocardium during fibrillation are highly complex, but they are also highly characteristic – almost like a fingerprint of fibrillation,” says Jan Christoph, a researcher at the Max Planck Institute for Dynamics and Self-Organization and the Heart Center at the University Medical Center Göttingen and lead author of the study. Together with Stefan Luther and an international team of researchers, the physicist has presented an imaging method that allows the fibrillating myocardium to be visually time-resolved in three dimensions, and therefore much more accurately than was previously possible – and it does so using clinically available high-resolution ultrasound equipment.

3D ultrasound measurements of mechanical filaments in the fibrillating heart. Credit: Max Planck Society

The new diagnostic method will help to make the treatment of ventricular fibrillation and possibly also atrial fibrillation more effective. The improved understanding of fibrillation, which can be achieved with the procedure, could help to advance the development of novel defibrillation techniques. In low-energy defibrillation, for example, the electrical pulses used to stop fibrillation are much weaker but much more targeted compared to the current, very painful method, which uses high-energy electric shocks. With the new form of ultrasound imaging, researchers could learn how to use low-energy pulses to restore normal heart rhythm.

The Göttingen-based researchers are now refining the method so that it will also be able to visualize the complex excitation dynamics, which occur during atrial fibrillation. In the future, cardiologists will be able to see exactly where pathological foci of excitation need to be removed by ablation. The new ultrasound method may also be helpful in the research, diagnosis and treatment of heart failure, during which the myocardial cells do not work effectively as their coordinated contractile movements are disrupted. Doctors would be able to determine the causes with the help of detailed ultrasound scans, enabling them to detect heart failure earlier and treat it more effectively.

Electrical waves cause mechanical contractions of the heart

Every heartbeat is triggered by electrical waves of excitation that propagate through the myocardium at high speed and cause the myocardial cells to contract. If these waves become turbulent, the result is cardiac arrhythmia. Doctors have long known that in cardiac arrhythmias, rotational electrical waves of excitation swirl through the heart muscle. Until now, their investigations of cardiac arrhythmias have focussed on such electrical vortices. However, they have not been able to ascertain a full picture of the dynamics, neither in the laboratory nor in the clinical setting. The MPIDS researchers took a different approach. Instead of concentrating on electrical stimulation, they looked at the twitching contractions of the fibrillating myocardium. “Until now, little importance was attached to the analysis of muscle contractions and deformations during fibrillation. In our measurements, however, we saw that electric vortices are always accompanied by corresponding vortex-shaped mechanical deformations,” physicist Jan Christoph explains.

Computer simulation of an electromechanical vortex in the heart muscle tissue. Credit: Max Planck Society

Ventricular fibrillation in 3-D

In order to visualize the trembling movements inside the heart muscle in three dimensions and to correlate them with the electrical excitation of the heart, the researchers developed new high-resolution ultrasound measuring methods. They also showed that these methods can be used in high-performance ultrasound equipment that is already in routine use in many cardiology institutions. By analyzing the image data of the muscle contractions, they were able to observe exactly how areas of contracted and relaxed muscle cells move in a vortex through the myocardium during fibrillation. They also observed filament-like structures that were previously known to physicists only in theory and from computer simulations. Such a filament-like structure resembles a thread and marks the eye of the whirlpool-like wave or cyclone moving through the myocardium. It is now possible for the first time to pinpoint these centres of the vortices inside the myocardium.

In addition to ultrasound scans, the researchers used high-speed cameras and fluorescent markers that reveal the electrophysiological processes in the myocardium. The images obtained confirmed that the mechanical vortices correspond very well with the electrical vortices.

According to the researchers in Göttingen, ultrasound technology has progressed tremendously in recent years in terms of image quality and imaging speeds, and the potential of modern ultrasound technology has yet to be fully exploited. “Together with the immensely increased computing power of modern computers and rapid advancements in computer graphics and digital image processing, new measurement and visualization possibilities are being created for investigating the heart. We can apply these developments in medicine today,” Jan Christoph says.

Electrical waves on the heart surface. Credit: Max Planck Society

From physics to medicine

The study is an example of successful interdisciplinary collaboration between physicists and doctors at the DZHK. “This revolutionary development will open up new treatment options for patients with cardiac arrhythmias. As early as 2018, we will use the new technology on our patients to better diagnose and treat cardiac arrhythmias and myocardial diseases,” says Gerd Hasenfuß, co-author of the study, Chairman of the Göttingen Heart Research Center Göttingen and the Heart Center at the University Medical Center Göttingen. Stefan Luther is certain of one thing: “Peering deeply into the inner dynamics of the heart marks a milestone in heart research and will decisively shape our understanding and treatment of heart disease in the future.”


Explore further:
Cause of killer cardiac disease identified by new method

More information:
J. Christoph et al. Electromechanical vortex filaments during cardiac fibrillation, Nature (2018). DOI: 10.1038/nature26001

Journal reference:
Nature

Provided by:
Max Planck Society

Tagged with:

About author

Related Articles