@article{GramGenslerAlbertovaetal.2022,
  author    = {Gram, Maximilian and Gensler, Daniel and Albertova, Petra and Gutjahr, Fabian Tobias and Lau, Kolja and Arias-Loza, Paula-Anahi and Jakob, Peter Michael and Nordbeck, Peter},
  title     = {Quantification correction for free-breathing myocardial T1ρ mapping in mice using a recursively derived description of a T\(_{1p}\)\(^{*}\) relaxation pathway},
  series = {Journal of Cardiovascular Magnetic Resonance},
  volume    = {24},
  journal   = {Journal of Cardiovascular Magnetic Resonance},
  number    = {1},
  doi       = {10.1186/s12968-022-00864-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300491},
  year      = {2022},
  abstract  = {Background Fast and accurate T1ρ mapping in myocardium is still a major challenge, particularly in small animal models. The complex sequence design owing to electrocardiogram and respiratory gating leads to quantification errors in in vivo experiments, due to variations of the T\(_{1p}\) relaxation pathway. In this study, we present an improved quantification method for T\(_{1p}\) using a newly derived formalism of a T\(_{1p}\)\(^{*}\) relaxation pathway. Methods The new signal equation was derived by solving a recursion problem for spin-lock prepared fast gradient echo readouts. Based on Bloch simulations, we compared quantification errors using the common monoexponential model and our corrected model. The method was validated in phantom experiments and tested in vivo for myocardial T\(_{1p}\) mapping in mice. Here, the impact of the breath dependent spin recovery time T\(_{rec}\) on the quantification results was examined in detail. Results Simulations indicate that a correction is necessary, since systematically underestimated values are measured under in vivo conditions. In the phantom study, the mean quantification error could be reduced from - 7.4\% to - 0.97\%. In vivo, a correlation of uncorrected T\(_{1p}\) with the respiratory cycle was observed. Using the newly derived correction method, this correlation was significantly reduced from r = 0.708 (p < 0.001) to r = 0.204 and the standard deviation of left ventricular T\(_{1p}\) values in different animals was reduced by at least 39\%. Conclusion The suggested quantification formalism enables fast and precise myocardial T\(_{1p}\) quantification for small animals during free breathing and can improve the comparability of study results. Our new technique offers a reasonable tool for assessing myocardial diseases, since pathologies that cause a change in heart or breathing rates do not lead to systematic misinterpretations. Besides, the derived signal equation can be used for sequence optimization or for subsequent correction of prior study results.},
  language  = {en}
}
@article{GhafoorNordbeckRitteretal.2022,
  author    = {Ghafoor, Hina and Nordbeck, Peter and Ritter, Oliver and Pauli, Paul and Schulz, Stefan M.},
  title     = {Can Religiosity and Social Support Explain Effects of Trait Emotional Intelligence on Health-Related Quality of Life: A Cross-Cultural Study},
  series = {Journal of Religion and Health},
  volume    = {61},
  journal   = {Journal of Religion and Health},
  number    = {1},
  issn      = {0022-4197},
  doi       = {10.1007/s10943-020-01163-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232823},
  pages     = {158-174},
  year      = {2022},
  abstract  = {Religion and social support along with trait emotional intelligence (EI) help individuals to reduce stress caused by difficult situations. Their implications may vary across cultures in reference to predicting health-related quality of life (HRQoL). A convenience sample of N = 200 chronic heart failure (CHF) patients was recruited at cardiology centers in Germany (n = 100) and Pakistan (n = 100). Results indicated that trait-EI predicted better mental component of HRQoL in Pakistani and German CHF patients. Friends as social support appeared relevant for German patients only. Qualitative data indicate an internal locus of control in German as compared to Pakistani patients. Strengthening the beneficial role of social support in Pakistani patients is one example of how the current findings may inspire culture-specific treatment to empower patients dealing with the detrimental effects of CHF.},
  language  = {en}
}
@article{SalingerHuLiuetal.2018,
  author    = {Salinger, Tim and Hu, Kai and Liu, Dan and Taleh, Scharoch and Herrmann, Sebastian and Oder, Daniel and Gensler, Daniel and M{\"u}ntze, Jonas and Ertl, Georg and Lorenz, Kristina and Frantz, Stefan and Weidemann, Frank and Nordbeck, Peter},
  title     = {Association between Comorbidities and Progression of Transvalvular Pressure Gradients in Patients with Moderate and Severe Aortic Valve Stenosis},
  series = {Cardiology Research and Practice},
  journal   = {Cardiology Research and Practice},
  doi       = {10.1155/2018/3713897},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227291},
  pages     = {3713897, 1-7},
  year      = {2018},
  abstract  = {Background. Fast progression of the transaortic mean gradient (P-mean) is relevant for clinical decision making of valve replacement in patients with moderate and severe aortic stenosis (AS) patients. However, there is currently little knowledge regarding the determinants affecting progression of transvalvular gradient in AS patients. Methods. This monocentric retrospective study included consecutive patients presenting with at least two transthoracic echocardiography examinations covering a time interval of one year or more between April 2006 and February 2016 and diagnosed as moderate or severe aortic stenosis at the final echocardiographic examination. Laboratory parameters, medication, and prevalence of eight known cardiac comorbidities and risk factors (hypertension, diabetes, coronary heart disease, peripheral artery occlusive disease, cerebrovascular disease, renal dysfunction, body mass index >= 30 Kg/m(2), and history of smoking) were analyzed. Patients were divided into slow (P-mean < 5 mmHg/year) or fast (P-mean >= 5 mmHg/year) progression groups. Results. A total of 402 patients (mean age 78 +/- 9.4 years, 58\% males) were included in the study. Mean follow-up duration was 3.4 +/- 1.9 years. The average number of cardiac comorbidities and risk factors was 3.1 +/- 1.6. Average number of cardiac comorbidities and risk factors was higher in patients in slow progression group than in fast progression group (3.3 +/- 1.5 vs 2.9 +/- 1.7; P = 0.036). Patients in slow progression group had more often coronary heart disease (49.2\% vs 33.6\%; P = 0.003) compared to patients in fast progression group. LDL-cholesterol values were lower in the slow progression group (100 +/- 32.6 mg/dl vs 110.8 +/- 36.6 mg/dl; P = 0.005). Conclusion. These findings suggest that disease progression of aortic valve stenosis is faster in patients with fewer cardiac comorbidities and risk factors, especially if they do not have coronary heart disease. Further prospective studies are warranted to investigate the outcome of patients with slow versus fast progression of transvalvular gradient with regards to comorbidities and risk factors.},
  language  = {en}
}
@article{GramGenslerWinteretal.2022,
  author    = {Gram, Maximilian and Gensler, Daniel and Winter, Patrick and Seethaler, Michael and Arias-Loza, Paula Anahi and Oberberger, Johannes and Jakob, Peter Michael and Nordbeck, Peter},
  title     = {Fast myocardial T\(_{1P}\) mapping in mice using k-space weighted image contrast and a Bloch simulation-optimized radial sampling pattern},
  series = {Magnetic Resonance Materials in Physics, Biology and Medicine},
  volume    = {35},
  journal   = {Magnetic Resonance Materials in Physics, Biology and Medicine},
  number    = {2},
  issn      = {1352-8661},
  doi       = {10.1007/s10334-021-00951-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-268903},
  pages     = {325-340},
  year      = {2022},
  abstract  = {Purpose T\(_{1P}\) dispersion quantification can potentially be used as a cardiac magnetic resonance index for sensitive detection of myocardial fibrosis without the need of contrast agents. However, dispersion quantification is still a major challenge, because T\(_{1P}\) mapping for different spin lock amplitudes is a very time consuming process. This study aims to develop a fast and accurate T\(_{1P}\) mapping sequence, which paves the way to cardiac T1ρ dispersion quantification within the limited measurement time of an in vivo study in small animals. Methods A radial spin lock sequence was developed using a Bloch simulation-optimized sampling pattern and a view-sharing method for image reconstruction. For validation, phantom measurements with a conventional sampling pattern and a gold standard sequence were compared to examine T\(_{1P}\) quantification accuracy. The in vivo validation of T\(_{1P}\) mapping was performed in N = 10 mice and in a reproduction study in a single animal, in which ten maps were acquired in direct succession. Finally, the feasibility of myocardial dispersion quantification was tested in one animal. Results The Bloch simulation-based sampling shows considerably higher image quality as well as improved T\(_{1P}\) quantification accuracy (+ 56\%) and precision (+ 49\%) compared to conventional sampling. Compared to the gold standard sequence, a mean deviation of - 0.46 ± 1.84\% was observed. The in vivo measurements proved high reproducibility of myocardial T\(_{1P}\) mapping. The mean T\(_{1P}\) in the left ventricle was 39.5 ± 1.2 ms for different animals and the maximum deviation was 2.1\% in the successive measurements. The myocardial T\(_{1P}\) dispersion slope, which was measured for the first time in one animal, could be determined to be 4.76 ± 0.23 ms/kHz. Conclusion This new and fast T\(_{1P}\) quantification technique enables high-resolution myocardial T\(_{1P}\) mapping and even dispersion quantification within the limited time of an in vivo study and could, therefore, be a reliable tool for improved tissue characterization.},
  language  = {en}
}
@article{GotschyBauerWinteretal.2017,
  author    = {Gotschy, Alexander and Bauer, Wolfgang R. and Winter, Patrick and Nordbeck, Peter and Rommel, Eberhard and Jakob, Peter M. and Herold, Volker},
  title     = {Local versus global aortic pulse wave velocity in early atherosclerosis: An animal study in ApoE\(^{-/-}\) mice using ultrahigh field MRI},
  series = {PLoS ONE},
  volume    = {12},
  journal   = {PLoS ONE},
  number    = {2},
  doi       = {10.1371/journal.pone.0171603},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171824},
  year      = {2017},
  abstract  = {Increased aortic stiffness is known to be associated with atherosclerosis and has a predictive value for cardiovascular events. This study aims to investigate the local distribution of early arterial stiffening due to initial atherosclerotic lesions. Therefore, global and local pulse wave velocity (PWV) were measured in ApoE\(^{-/-}\) and wild type (WT) mice using ultrahigh field MRI. For quantification of global aortic stiffness, a new multi-point transit-time (TT) method was implemented and validated to determine the global PWV in the murine aorta. Local aortic stiffness was measured by assessing the local PWV in the upper abdominal aorta, using the flow/area (QA) method. Significant differences between age matched ApoE\(^{-/-}\) and WT mice were determined for global and local PWV measurements (global PWV: ApoE\(^{-/-}\): 2.7 ±0.2m/s vs WT: 2.1±0.2m/s, P<0.03; local PWV: ApoE\(^{-/-}\): 2.9±0.2m/s vs WT: 2.2±0.2m/s, P<0.03). Within the WT mouse group, the global PWV correlated well with the local PWV in the upper abdominal aorta (R\(^2\) = 0.75, P<0.01), implying a widely uniform arterial elasticity. In ApoE\(^{-/-}\) animals, however, no significant correlation between individual local and global PWV was present (R\(^2\) = 0.07, P = 0.53), implying a heterogeneous distribution of vascular stiffening in early atherosclerosis. The assessment of global PWV using the new multi-point TT measurement technique was validated against a pressure wire measurement in a vessel phantom and showed excellent agreement. The experimental results demonstrate that vascular stiffening caused by early atherosclerosis is unequally distributed over the length of large vessels. This finding implies that assessing heterogeneity of arterial stiffness by multiple local measurements of PWV might be more sensitive than global PWV to identify early atherosclerotic lesions.},
  language  = {en}
}
@article{LiuHuLauetal.2021,
  author    = {Liu, Dan and Hu, Kai and Lau, Kolja and Kiwitz, Tobias and Robitzkat, Katharina and Hammel, Clara and Lengenfelder, Bj{\"o}rn Daniel and Ertl, Georg and Frantz, Stefan and Nordbeck, Peter},
  title     = {Impact of diastolic dysfunction on outcome in heart failure patients with mid-range or reduced ejection fraction},
  series = {ESC Heart Failure},
  volume    = {8},
  journal   = {ESC Heart Failure},
  number    = {4},
  doi       = {10.1002/ehf2.13352},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258894},
  pages     = {2802-2815},
  year      = {2021},
  abstract  = {Aims The role of diastolic dysfunction (DD) in prognostic evaluation in heart failure (HF) patients with impaired systolic function remains unclear. We investigated the impact of echocardiography-defined DD on survival in HF patients with mid-range (HFmrEF, EF 41-49\%) and reduced ejection fraction (HFrEF, EF < 40\%). Methods and results A total of 2018 consecutive hospitalized HF patients were retrospectively included and divided in two groups based on baseline EF: HFmrEF group (n = 951, aged 69 ± 13 years, 74.2\% male) and HFrEF group (n = 1067, aged 68 ± 13 years, 76.3\% male). Clinical data were collected and analysed. All patients completed ≥1 year clinical follow-up. The primary endpoint was defined as all-cause death (including heart transplantation) and cardiovascular (CV)-related death. All-cause mortality (30.8\% vs. 24.9\%, P = 0.003) and CV mortality (19.1\% vs. 13.5\%, P = 0.001) were significantly higher in the HFrEF group than the HFmrEF group during follow-up [median 24 (13-36) months]. All-cause mortality increased in proportion to DD severity (mild, moderate, and severe) in either HFmrEF (17.1\%, 25.4\%, and 37.0\%, P < 0.001) or HFrEF (18.9\%, 30.3\%, and 39.2\%, P < 0.001) patients. The risk of all-cause mortality [hazard ratio (HR) = 1.347, P = 0.015] and CV mortality (HR = 1.508, P = 0.007) was significantly higher in HFrEF patients with severe DD compared with non-severe DD after adjustment for identified clinical and echocardiographic covariates. For HFmrEF patients, severe DD was independently associated with increased all-cause mortality (HR = 1.358, P = 0.046) but not with CV mortality (HR = 1.155, P = 0.469). Conclusions Echocardiography-defined severe DD is independently associated with increased all-cause mortality in patients with HFmrEF and HFrEF.},
  language  = {en}
}
@article{HeidenreichWengDonhauseretal.2019,
  author    = {Heidenreich, Julius F. and Weng, Andreas M. and Donhauser, Julian and Greiser, Andreas and Chow, Kelvin and Nordbeck, Peter and Bley, Thorsten A. and K{\"o}stler, Herbert},
  title     = {T1- and ECV-mapping in clinical routine at 3 T: differences between MOLLI, ShMOLLI and SASHA},
  series = {BMC Medical Imaging},
  volume    = {19},
  journal   = {BMC Medical Imaging},
  doi       = {10.1186/s12880-019-0362-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201999},
  pages     = {59},
  year      = {2019},
  abstract  = {Background T1 mapping sequences such as MOLLI, ShMOLLI and SASHA make use of different technical approaches, bearing strengths and weaknesses. It is well known that obtained T1 relaxation times differ between the sequence techniques as well as between different hardware. Yet, T1 quantification is a promising tool for myocardial tissue characterization, disregarding the absence of established reference values. The purpose of this study was to evaluate the feasibility of native and post-contrast T1 mapping methods as well as ECV maps and its diagnostic benefits in a clinical environment when scanning patients with various cardiac diseases at 3 T. Methods Native and post-contrast T1 mapping data acquired on a 3 T full-body scanner using the three pulse sequences 5(3)3 MOLLI, ShMOLLI and SASHA in 19 patients with clinical indication for contrast enhanced MRI were compared. We analyzed global and segmental T1 relaxation times as well as respective extracellular volumes and compared the emerged differences between the used pulse sequences. Results T1 times acquired with MOLLI and ShMOLLI exhibited systematic T1 deviation compared to SASHA. Myocardial MOLLI T1 times were 19\% lower and ShMOLLI T1 times 25\% lower compared to SASHA. Native blood T1 times from MOLLI were 13\% lower than SASHA, while post-contrast MOLLI T1-times were only 5\% lower. ECV values exhibited comparably biased estimation with MOLLI and ShMOLLI compared to SASHA in good agreement with results reported in literature. Pathology-suspect segments were clearly differentiated from remote myocardium with all three sequences. Conclusion Myocardial T1 mapping yields systematically biased pre- and post-contrast T1 times depending on the applied pulse sequence. Additionally calculating ECV attenuates this bias, making MOLLI, ShMOLLI and SASHA better comparable. Therefore, myocardial T1 mapping is a powerful clinical tool for classification of soft tissue abnormalities in spite of the absence of established reference values.},
  language  = {en}
}
@article{TolstikAliGuoetal.2022,
  author    = {Tolstik, Elen and Ali, Nairveen and Guo, Shuxia and Ebersbach, Paul and M{\"o}llmann, Dorothe and Arias-Loza, Paula and Dierks, Johann and Schuler, Irina and Freier, Erik and Debus, J{\"o}rg and Baba, Hideo A. and Nordbeck, Peter and Bocklitz, Thomas and Lorenz, Kristina},
  title     = {CARS imaging advances early diagnosis of cardiac manifestation of Fabry disease},
  series = {International Journal of Molecular Sciences},
  volume    = {23},
  journal   = {International Journal of Molecular Sciences},
  number    = {10},
  issn      = {1422-0067},
  doi       = {10.3390/ijms23105345},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284427},
  year      = {2022},
  abstract  = {Vibrational spectroscopy can detect characteristic biomolecular signatures and thus has the potential to support diagnostics. Fabry disease (FD) is a lipid disorder disease that leads to accumulations of globotriaosylceramide in different organs, including the heart, which is particularly critical for the patient's prognosis. Effective treatment options are available if initiated at early disease stages, but many patients are late- or under-diagnosed. Since Coherent anti-Stokes Raman (CARS) imaging has a high sensitivity for lipid/protein shifts, we applied CARS as a diagnostic tool to assess cardiac FD manifestation in an FD mouse model. CARS measurements combined with multivariate data analysis, including image preprocessing followed by image clustering and data-driven modeling, allowed for differentiation between FD and control groups. Indeed, CARS identified shifts of lipid/protein content between the two groups in cardiac tissue visually and by subsequent automated bioinformatic discrimination with a mean sensitivity of 90-96\%. Of note, this genotype differentiation was successful at a very early time point during disease development when only kidneys are visibly affected by globotriaosylceramide depositions. Altogether, the sensitivity of CARS combined with multivariate analysis allows reliable diagnostic support of early FD organ manifestation and may thus improve diagnosis, prognosis, and possibly therapeutic monitoring of FD.},
  language  = {en}
}
@article{ChenLiuWeidemannetal.2021,
  author    = {Chen, Menjia and Liu, Dan and Weidemann, Frank and Lengenfelder, Bj{\"o}rn Daniel and Ertl, Georg and Hu, Kai and Frantz, Stefan and Nordbeck, Peter},
  title     = {Echocardiographic risk factors of left ventricular thrombus in patients with acute anterior myocardial infarction},
  series = {ESC Heart Failure},
  volume    = {8},
  journal   = {ESC Heart Failure},
  number    = {6},
  doi       = {10.1002/ehf2.13605},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261067},
  pages     = {5248-5258},
  year      = {2021},
  abstract  = {Aims This study aimed to identify echocardiographic determinants of left ventricular thrombus (LVT) formation after acute anterior myocardial infarction (MI). Methods and results This case-control study comprised 55 acute anterior MI patients with LVT as cases and 55 acute anterior MI patients without LVT as controls, who were selected from a cohort of consecutive patients with ischemic heart failure in our hospital. The cases and controls were matched for age, sex, and left ventricular ejection fraction. LVT was detected by routine/contrast echocardiography or cardiac magnetic resonance imaging during the first 3 months following MI. Formation of apical aneurysm after MI was independently associated with LVT formation [72.0\% vs. 43.5\%, odds ratio (OR) = 5.06, 95\% confidence interval (CI) 1.65-15.48, P = 0.005]. Echocardiographic risk factors associated with LVT formation included reduced mitral annular plane systolic excursion (<7 mm, OR = 4.69, 95\% CI 1.84-11.95, P = 0.001), moderate-severe diastolic dysfunction (OR = 2.71, 95\% CI 1.11-6.57, P = 0.028), and right ventricular (RV) dysfunction [reduced tricuspid annular plane systolic excursion < 17 mm (OR = 5.48, 95\% CI 2.12-14.13, P < 0.001), reduced RV fractional area change < 0.35 (OR = 3.32, 95\% CI 1.20-9.18, P = 0.021), and enlarged RV mid diameter (per 5 mm increase OR = 1.62, 95\% CI 1.12-2.34, P = 0.010)]. Reduced tricuspid annular plane systolic excursion (<17 mm) significantly associated with increased risk of LVT in anterior MI patients (OR = 3.84, 95\% CI 1.37-10.75, P = 0.010), especially in those patients without apical aneurysm (OR = 5.12, 95\% CI 1.45-18.08, P = 0.011), independent of body mass index, hypertension, anaemia, mitral annular plane systolic excursion, and moderate-severe diastolic dysfunction. Conclusions Right ventricular dysfunction as determined by reduced TAPSE or RV fractional area change is independently associated with LVT formation in acute anterior MI patients, especially in the setting of MI patients without the formation of an apical aneurysm. This study suggests that besides assessment of left ventricular abnormalities, assessment of concomitant RV dysfunction is of importance on risk stratification of LVT formation in patients with acute anterior MI.},
  language  = {en}
}
@article{WeidemannMaierStoerketal.2016,
  author    = {Weidemann, Frank and Maier, Sebastian K. G. and St{\"o}rk, Stefan and Brunner, Thomas and Liu, Dan and Hu, Kai and Seydelmann, Nora and Schneider, Andreas and Becher, Jan and Canan-K{\"u}hl, Sima and Blaschke, Daniela and Bijnens, Bart and Ertl, Georg and Wanner, Christoph and Nordbeck, Peter},
  title     = {Usefulness of an implantable loop recorder to detect clinically relevant arrhythmias in patients with advanced fabry cardiomyopathy},
  series = {The American Journal of Cardiology},
  volume    = {118},
  journal   = {The American Journal of Cardiology},
  number    = {2},
  doi       = {10.1016/j.amjcard.2016.04.033},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188093},
  pages     = {264-274},
  year      = {2016},
  abstract  = {Patients with genetic cardiomyopathy that involves myocardial hypertrophy often develop clinically relevant arrhythmias that increase the risk of sudden death. Consequently, guidelines for medical device therapy were established for hypertrophic cardiomyopathy, but not for conditions with only anecdotal evidence of arrhythmias, like Fabry cardiomyopathy. Patients with Fabry cardiomyopathy progressively develop myocardial fibrosis, and sudden cardiac death occurs regularly. Because 24-hour Holier electrocardiograms (ECGs) might not detect clinically important arrhythmias, we tested an implanted loop recorder for continuous heart rhythm surveillance and determined its impact on therapy. This prospective study included 16 patients (12 men) with advanced Fabry cardiomyopathy, relevant hypertrophy, and replacement fibrosis in "loco typico." No patients previously exhibited clinically relevant arrhythmias on Holier ECGs. Patients received an implantable loop recorder and were prospectively followed with telemedicine for a median of 1.2 years (range 0.3 to 2.0 years). The primary end point was a clinically meaningful event, which required a therapy change, captured with the loop recorder. Patients submitted data regularly (14 +/- 11 times per month). During follow-up, 21 events were detected (including 4 asystole, i.e., ECG pauses >= 3 seconds) and 7 bradycardia events; 5 episodes of intermittent atrial fibrillation (>3 minutes) and 5 episodes of ventricular tachycardia (3 sustained and 2 nonsustained). Subsequently, as defined in the primary end point, 15 events leaded to a change of therapy. These patients required therapy with a pacemaker or cardioverter defibrillator implantation and/or anticoagulation therapy for atrial fibrillation. In conclusion, clinically relevant arrhythmias that require further device and/or medical therapy are often missed with Holier ECGs in patients with advanced stage Fabry cardiomyopathy, but they can be detected by telemonitoring with an implantable loop recorder.},
  language  = {en}
}