@article{BeningSalesAlhussinietal.2021,
  author    = {Bening, Constanze and Sales, Virna L. and Alhussini, Khaled and Radakovic, Dejan and Cris Benitez, R. and Madrahimov, Nodir and Keller, Daria M. and Leyh, Rainer},
  title     = {Clinically inapparent right heart dysfunction is associated with reduced myofilament force development in coronary artery disease},
  series = {BMC Cardiovascular Disorders},
  volume    = {21},
  journal   = {BMC Cardiovascular Disorders},
  number    = {1},
  doi       = {10.1186/s12872-021-01926-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259213},
  pages     = {125},
  year      = {2021},
  abstract  = {Background Right ventricular dysfunction after CABG is associated with poor peri- and postoperative outcomes. We aimed to identify clinical and experimental predictors for preoperative inapparent right ventricular dysfunction and therefore hypothesized that reduced myofilament force development as well as altered levels of biomarkers might predict inapparent right ventricular dysfunction. Methods From 08/2016 to 02/2018, 218 patients scheduled for CABG were divided into two groups (TAPSE ≥ 20 mm, n = 178; TAPSE < 20 mm, n = 40). Baseline serum samples for biomarkers (Galectin, TGFß1, N Acyl-SDMA, Arginine, ADMA and Pentraxin-3), clinical laboratory and transthoracic echocardiographic parameters were evaluated. To examine the myocardial apparatus of the right ventricle intraoperative right auricular tissue was harvested for stepwise skinned fiber force measurements. Results Patients with TAPSE < 20 mm had a higher incidence of DM (55 vs. 34\%, p = 0.018), preoperative AFib (43 vs. 16\%, p < 0.001), reduced GFR (67 ± 18 vs. 77 ± 24 ml/min/1.73 m\(^2\), p = 0.013), larger LA area (22 ± 6 vs. 20 ± 5 cm\(^2\), p = 0.005) and reduced LVEF (50 vs. 55\%, p = 0.008). Furthermore, higher serum ADMA (0.70 ± 0.13 vs. 0.65 ± 0.15 µmol/l, p = 0.046) and higher serum Pentraxin-3 levels (3371 ± 1068 vs. 2681 ± 1353 pg/dl, p = 0.004) were observed in these patients. Skinned fiber force measurements showed significant lower values at almost every step of calcium concentration (pCa 4.52 to pCa 5.5, p < 0.01 and pCa 5.75-6.0, p < 0.05). Multivariable analysis revealed DM (OR 2.53, CI 1.12-5.73, Euro Score II (OR 1.34, CI 1.02-1.78), preoperative AF (OR 4.86, CI 2.06-11.47), GFR (OR 7.72, CI 1.87-31.96), albumin (OR 1.56, CI 0.52-2.60), Pentraxin-3 (OR 19.68, CI 14.13-25.24), depressed LVEF (OR 8.61, CI 6.37-10.86), lower force values: (pCa 5.4; OR 2.34, CI 0.40-4.29 and pCa 5.2; OR 2.00, CI 0.39-3.60) as predictors for clinical inapparent right heart dysfunction. Conclusions These preliminary data showed that inapparent right heart dysfunction in CAD is already associated with reduced force development of the contractile apparatus.},
  language  = {en}
}
@article{BeningHamoudaLeyh2016,
  author    = {Bening, C. and Hamouda, K. and Leyh, R.},
  title     = {Sex differences in volume overload in skinned fibers},
  series = {BMC Cardiovascular Disorders},
  volume    = {16},
  journal   = {BMC Cardiovascular Disorders},
  number    = {197},
  doi       = {10.1186/s12872-016-0370-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147896},
  year      = {2016},
  abstract  = {Background The impact of sex on cardiac morphology and function in chronic volume overload has been described in detail. However, the relation between sex and contractile properties at the actin-myosin level has not been well defined. Therefore, we evaluated the influence of sex on the contractile capacities of patients with chronic volume overload. Methods In 36 patients (18 males, 65 ± 9 years; 18 females, 65 ± 13 years) scheduled for elective mitral valve surgery due to severe mitral regurgitation (MR) with preserved left ventricular function, right auricle samples were obtained prior to extracorporal circulation. The fibers were prepared and skinned and exposed to a gradual increase in the calcium concentration (from pCa of 6.5-4.0) for calcium-induced force-developing measurements. Calcium sensitivity was also measured and recorded. Results The pCa-force relationship of the fibers obtained from males and females was significantly different, with the force values of the female fibers greater than those of male fibers at maximum calcium concentrations (pCa of 4.0: 3.6 ± 0.3 mN versus 3.2 ± 0.4 mN, p 0.02) and pCa of 4.5 2.6 ± 0.6 versus 2.0 ± 0.5, p 0.002). In contrast, the force values of female fibers were lower at mean calcium concentrations compared to those of male fibers (at 5.5 and pCa of 6.0: 1.0 ± 0.3 mN versus 1.2 ± 0.5 mN, p 0.04; 0.61 ± 0.05 versus 0.88 ± 0.09, p 0.04). Calcium sensitivity was observed at pCa of 5.0 in females and pCa of 4.5 in males. Conclusion This study demonstrated that female fibers from patients exposed to chronic volume overload developed higher force values at a given calcium concentration compared to fibers from male patients. We assume that female patients might tap the full force potential, which is required when exposed to the highest calcium concentrations in our experimental cycle. The calcium sensitivity among genders was significantly different, with the results suggesting that males have higher calcium sensitivity and might compensate for lower force values at maximal calcium concentrations by a higher affinity for calcium. Hence, female patients with MR seem to work more "energy efficient".},
  language  = {en}
}