Conditions causing arrhythmia are among the most common heart conditions. A study by Professor Georg Schmidt from the Technical University of Munich (TUM) has shown for the first time that the night breathing rate can help with important predictions: It is an indication of whether a defibrillator helps by ‘extends the life of patients with arrhythmia.
Sudden cardiac death is one of the leading causes of mortality in western industrialized countries. It can be prevented with a portable cardioverter defibrillator (ICD). This automatically detects life-threatening heart rhythms and sends out electrical signals to stop them. The guidelines recommend the application of ICDn in patients with severely weakened pump action of the left ventricle. According to the German Heart Surgery Report, more than 42,000 defibrillators were installed in Germany in 2018.
However, there are doubts about the efficacy of ICDn insertion. The latest report on heart surgery by the German Heart Foundation also notes that the benefits of defibrillator therapy are not as clear as previously believed. In addition, they are often made up of relatively common complications arising both during and after the implantation procedure.
Predictive value of night breathing rate
Researchers at TUM have now proven that the night – time breathing rate of heart patients – which has received little attention to date – cannot help predict the success of ICD treatment. Between May 2014 and September 2018 they monitored 1,971 cardiac patients at 44 European cardiac centers. 1,363 of the patients received ICD, while the control group was treated conservatively. The different treatment options were tested based on the availability of ICD therapy at the participating European centers. As a result, the study was not randomized. However, the resulting biases were compensated for by sophisticated statistical analysis. The study is now published in eClinicalMedicine, an open access magazine produced by the renowned magazine The Lancet.
In each group the scientists measured the average night breathing rate between midnight and 6 in the morning based on the ECG protocol. ICD patients had a survival benefit of 31.3 percent across the control group. At the same time, a significant association was observed between low night breathing rate and reduced mortality: ICD patients with a survival rate of less than 18 breaths per minute had a 50 percent survival rate compared with the control group, while those with higher night relief a rate that did not have a survival benefit through the defibrillator.
So far biosignal has been neglected by cartographers
“The breathing rate was largely ignored as a biologist in the field of cartography,” says Dr. Georg Schmidt, the last author of the study, who heads the working group for biosignal processing at TUM Klinikum rechts der Isar university hospital. “Our decisions will now focus more on this parameter,” says Dr. Schmidt, noting that the study demonstrates the predictive value of respiratory frequency for therapeutic efficacy. “Especially in borderline cases, monitoring the patient’s breathing rate can help decide on the right treatment.”
Random examination is required
Against this background, Schmidt, who is also chair of the TUM Ethics Commission, considers that it would be reasonable to focus on random analysis against established guidelines.
This would involve dividing the patients observed not to have benefited from the ICD in our study into two groups, with one with ICD applied and the other involved. receive maintenance treatment. If a randomized study of this type reveals that cardiac patients with a higher nighttime respiratory rate do not benefit from the ICD implant, they may be prevented by this invasive treatment in the future. “
Professor Georg Schmidt, Final Author of the study
Source:
Munich Technical University (TUM)
Magazine Reference:
Dommasch, M., et al. (2020) Night breathing rate predicts ICD benefit: A prospective, controlled, multicenter cohort study. EClinicalMedicine. doi.org/10.1016/j.eclinm.2020.100695.