Publications by authors named "Niklas Neumann"

Background: There has been an increasing interest in the development and prevention of sports injuries from a complex dynamic systems perspective. From this perspective, injuries may occur following critical fluctuations in the psychophysiological state of an athlete. Our objective was to quantify these so-called Early Warning Signals (EWS) as a proof of concept to determine their explanatory performance for injuries.

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Cardiac output can be estimated non-invasively by electrical cardiometry with the ICON® monitor (Osypka Medical GmbH, Berlin, Germany). Conflicting results have been reported regarding the cardiac output measurement performance of electrical cardiometry. In this prospective method comparison study, we compared cardiac output measured using electrical cardiometry (EC-CO; test method) with cardiac output measured using intermittent pulmonary artery thermodilution (PATD-CO; reference method) in patients after coronary artery bypass graft (CABG) surgery.

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Athletes are exposed to various psychological and physiological stressors, such as losing matches and high training loads. Understanding and improving the resilience of athletes is therefore crucial to prevent performance decrements and psychological or physical problems. In this review, resilience is conceptualized as a dynamic process of bouncing back to normal functioning following stressors.

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Purpose: The study of load and recovery gained significant interest in the last decades, given its important value in decreasing the likelihood of injuries and improving performance. So far, findings are typically reported on the group level, whereas practitioners are most often interested in applications at the individual level. Hence, the aim of the present research is to examine to what extent group-level statistics can be generalized to individual athletes, which is referred to as the "ergodicity issue.

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Objectives: We aimed to elucidate the correlation between expression patterns of aortic tissue microRNAs and the aortopathy formation in bicuspid aortic valve (BAV) disease.

Methods: All 65 patients who underwent elective aortic valve repair/replacement +/- proximal aortic replacement due to BAV disease with or without concomitant aortic aneurysm were identified from our BAV registry. Aortic tissue was collected intraoperatively from the ascending aorta at the greater and lesser curvature.

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Background: Aortic valve (AV) repair has evolved towards a treatment alternative in young patients with AV regurgitation and was accompanied by the development of surgical repair strategies. An efficient and reproducible AV annulus stabilization (i.e.

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Objective: Aortic size-based criteria are of limited value in the prediction of aortic events, while most aortic events occur in patients with proximal aortic diameters < 50 mm. Serological biomarkers and especially circulating microRNAs (miRNAs) have been proposed as an elegant tool to improve risk stratification in patients with different aortopathies. Therefore, we aimed to evaluate the levels of circulating miRNAs in a surgical cohort of patients presenting with bicuspid aortic valve disease and distinct valvulo-aortic phenotypes.

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Objective:  Long-term prognosis of patients with aortic regurgitation (AR) and reduced left ventricular ejection fraction (LVEF) who undergo aortic valve surgery (AVS) is unknown. Due to the congenital origin, bicuspid aortic valve (BAV) morphotype might be associated with a more severe cardiomyopathy. We aimed to evaluate the LVEF recovery after aortic valve replacement (AVR) surgery in patients with AR and reduced preoperative LVEF.

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MicroRNAs (miRNAs) may serve as elegant tool to improve risk stratification in bicuspid aortic valve (BAV)-associated aortopathy. However, the exact pathogenetic pathway by which miRNAs impact aortopathy progression is unknown. Herewith, we aimed to analyze the association between circulating miRNAs and rare variants of aortopathy-related genes.

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Bicuspid aortic valve (BAV) disease is the most common congenital malformation of the human heart with a prevalence of 1⁻2% in the general population. More than half of patients with a BAV present with a dilated proximal aorta (so-called bicuspid aortopathy) which is associated with an enhanced risk of life-threatening aortic complications. Up to now, the pathogenesis of bicuspid aortopathy as well as the risk stratification of aortic complications has not yet been sufficiently clarified.

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Objectives: We herein report a single-center experience with the Portico TAVI system. Main focus was set on outcomes in patients with impaired left ventricular (LV) function and predictors for permanent pacemaker (PPM) implantation.

Methods: Between 05/2014 and 10/2017, 106 consecutive patients received TAVI using the Portico device.

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Objectives: The growing experience in aortic valve (AV) repair showed that annular stabilization is a crucial component to achieve stable long-term results after AV repair. Dynamic changes in the AV annulus during the cardiac cycle may have an impact on annuloplasty design.

Methods: We retrospectively analysed full cardiac cycle multislice computed tomography data from 58 consecutive patients (mean age 75.

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Objectives: We aimed to evaluate the impact of microRNAs to predict the bicuspid aortic valve (BAV)-associated aortopathy.

Methods: Sixty-three BAV patients (mean age 47 ± 11 years, 92% men) with root dilatation, who underwent aortic valve ± proximal aortic surgery (mean post-AVR follow-up 10.3 ± 6.

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Background: Valve-preserving aortic surgery is increasingly used in acute aortic dissection type A (AADA). The object of this study was to compare the long-term results of aortic root remodeling (remodeling) for patients with and without AADA.

Methods and results: Between October 1995 and December 2013, 776 patients underwent valve-preserving root replacement, of whom 59 patients with AADA (<2 weeks from onset, 56±16 years, 48 male) underwent remodeling (the remodeling-group); 7 patients had bicuspid anatomy (12%), 3 had Marfan syndrome (5%), and 1 had undergone previous cardiac surgery (2%).

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Objectives: To evaluate the long-term results of aortic root remodeling in the setting of acute aortic dissection type A (AADA).

Methods: Between October 1995 and May 2013, a total of 215 patients were treated surgically for AADA. Of these, 59 patients with AADA (<2 weeks from onset, age 56 ± 16 years, 53 males) with a root diameter of ≥43 to 45 mm (depending on patient size) underwent aortic root remodeling and were analyzed further.

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