Clinical Hemorheology and Microcirculation - Volume 64, issue 3

Authors: Jung, F. | Rampling, M.

Article Type: Editorial

DOI: 10.3233/CH-168108

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 251-254, 2016

Authors: Gori, Tommaso | von Henning, Urs | Muxel, Selina | Schaefer, Sarina | Fasola, Federica | Vosseler, Marcus | Schnorbus, Boris | Binder, Harald | Parker, John D. | Münzel, Thomas

Article Type: Research Article

Abstract: INTRODUCTION: Flow-mediated dilation (FMD) quantifies endothelium-dependent vasomotor responses to short-term increases in blood flow. Low-flow mediated vasoconstriction (L-FMC) has been more recently introduced as additional measure of endothelial function, and its relationship with changes in blood flow, cardiovascular risk factors and FMD ha∧ s been less well characterized. MATERIALS AND METHODS: We evaluated radial artery FMD and L-FMC along with the changes in blood flow and shear rate/stress in 584 patients with known or suspected coronary artery disease (72.9% men, mean age 67+/–11 years). Baseline blood flow and shear rate showed a modest association with radial artery …FMD and L-FMC (R2  = 0.04 and R2  = 0.02, P  < 0.0001). Resting diameter showed a stronger association with FMD but not with L-FMC (R2  = 0.11, P  < 0.0001 and R2  = 0.005, P  = 0.09). Analysis with generalized additive models showed that age, sex and presence and extent of coronary artery disease were strongly related to both endothelial function measures (P  < 0.001 for both), but they explained only 12.4% and 10.1% of the variance in L-FMC and FMD. When the corresponding changes in blood flow were added to these statistical models, the % of variance explained raised to 20.4% and 17.7% for L-FMC and FMD. L-FMC was a strong predictor of FMD even after correction for the changes in blood flow. DISCUSSION: Changes in blood flow are the most important determinants of both L-FMC and FMD. These observations support the concept that both FMD and L-FMC measure endothelium-dependent, shear-induced, vasomotion. Show more

Keywords: Endothelium/vascular type/nitric oxide, pathophysiology, coronary circulation

DOI: 10.3233/CH-168102

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 255-266, 2016

Authors: Orphal, Dörte | Gori, Tommaso

Article Type: Research Article

Abstract: A number of studies consistently report higher rates of all clinical outcomes including postinfarction mortality, need for repeat revascularization, and reinfarction in women with cardiovascular diseases than in men. As well, the gender gap in the prevalence of cardiovascular diseases decreases progressively with increasing age. Yet, the diagnosis and treatment of these diseases differ between genders and women remain underdiagnosed for coronary heart disease. In a recent retrospective analysis we showed that, along with vessel under study and age, gender is a determinant of adenosine responses during studies of fractional flow reserve, an effect that was probably due to differences …in microvascular function and that influenced the interpretation of fractional flow reserve data. These data demonstrate that not only the clinical presentation is different, but also the diagnostic approach to coronary artery disease might differ between sexes. A gap still exists in the understanding of the mechanisms, awareness, and treatment of coronary artery disease in women, but also, as we show, in the application of diagnostic modalities that are well established in men. Show more

Keywords: Microvascular function, coronary, sex

DOI: 10.3233/CH-168103

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 267-272, 2016

Authors: Ullrich, Helen | Gori, Tommaso

Article Type: Research Article

Abstract: Triple anticoagulant therapy is necessary in patients who are at increased risk for both arterial (in stent) and venous thrombosis, or have atrial fibrillation. Triple therapy however also poses a very high risk for bleeding events, particularly because this subset of patients is particularly frail due to the high incidence of comorbidities and advanced age. Very little randomized studies have tested the impact of the many possible combinations of anticoagulant/antiaggregant drugs, and surveys among practicing physicians show that the use of off-label therapies is very common. In a recent survey from our group, we observed that physicians are very divided …in terms of what therapy should be recommended to patients with indication to anticoagulation and with a history of stenting. The use of novel anticoagulants was as frequent as that of vitamin K antagonists, and the duration of triple therapy was very variable. While these data probably show that decisions are usually taken on an individual basis, considering the patient’s risk of ischemia and hemorrhagic events, much of this variability probably depends on the fact that, failing randomized trials, guidelines in this area are relatively less specific than in other ones. Show more

Keywords: Antiplatelet therapy, coronary stenting, anticoagulants

DOI: 10.3233/CH-168104

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 273-278, 2016

Authors: Kiouptsi, Klytaimnistra | Reinhardt, Christoph

Article Type: Research Article

Abstract: The plasmatic coagulation system is tightly controlled by natural anticoagulant mechanisms, preventing thrombosis to ensure the supply of tissues with oxygen and nutrients without provoking susceptibility to bleeding diatheses. The membrane receptor tissue factor (TF) is the principal initiator of coagulation, forming a high affinity complex with coagulation factor VIIa, thus catalyzing quantitative formation of the coagulation factor Xa. While it has been well-established that the TF-VIIa complex is efficiently blocked by factor Xa associated with tissue factor pathway inhibitor (TFPI), it was uncovered during the last decade that TF contains an intramolecular allosteric disulfide, which is prone to reduction …and is crucial for TF’s procoagulant and prothrombotic function. The compromised integrity of the allosteric TF disulfide pair Cys186/Cys209 was demonstrated to be responsible for the cryptic nature of TF procoagulant activity on monocytes and other cell types as well as in mouse thrombosis models. Cell surface associated protein disulfide-isomerases (PDI) were identified as activators of cryptic tissue factor. Here, we review this current concept of TF de-encryption by PDI oxidoreductases that have become interesting targets for the development of new antithrombotic treatment strategies. Show more

Keywords: Thrombosis, tissue factor, protein disulfide-isomerase, PDI

DOI: 10.3233/CH-168106

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 279-286, 2016

Authors: Lamby, P. | Jung, F. | Falter, J. | Mrowietz, C. | Graf, S. | Schellenberg, L. | Platz Batista da Silva, N. | Prantl, L. | Franke, R.P. | Jung, E.M.

Article Type: Research Article

Abstract: BACKGROUND: Intra-arterial administration of radiographic contrast media (CM) is discussed to impair renal perfusion. The pathogenesis of contrast-induced Nephropathy (CIN) is still not clarified. OBJECTIVE: This trial was performed to prove the effects of two CM with different molecular structure on renal perfusion. METHODS: A prospective, randomized study on 16 pigs was designed to compare the outcome after application of a low-osmolar iodinated CM (770 mOsm/kg H2 O – Group1) and an iso-osmolar iodinated CM (290 mOsm/kg H2 o – Group2). Color Coded Doppler Sonography (LOGIQ E9, GE, Milwaukee, USA) was applied for measuring the Renal …Resistive Index (RRI) before and after the first, fifth, and tenth bolus of CM. Statistics was performed using analysis of variance for repeated measurements with the Factor “CM”. RESULTS: All flow spectra were documented free of artifacts and Peak Systolic Velocity (PSV), Enddiastolic Velocity (EDV) and RRI respectively could be calculated. Mean PSV in Group 1 led to a decrease while in Group 2 PSV showed a significant increase after CM (p  = 0,042). The course of the mean EDV in both groups deferred accordingly (p  = 0,033). Mean RRI over time significantly deferred in both groups (p  = 0,001). It showed a biphasic course in Group 2 and a decrease over time in Group 2. CONCLUSION: While iso-osmolar CM induced an increase of PSV and EDV together with a decrease of RRI, low-osmolar CM could not show this effect or rather led to the opposite. Show more

Keywords: Renal perfusion, radiographic contrast media, contrast agent, CCDS, color coded Doppler sonography, contrast-induced Nephropathy, CIN

DOI: 10.3233/CH-168110

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 287-295, 2016

Authors: Gerk, U. | Mrowietz, C. | Sternitzky, R. | Franke, R.P. | Spitzer, S.G. | Jung, F.

Article Type: Research Article

Abstract: Radiographic contrast media (RCM) can initiate microcirculatory disorders. This study was performed to investigate effects of Ioxaglate on the cutaneous microcirculation. The investigation was carried out as prospective randomized double-blind comparison in parallel-group design on two groups of n  = 10 patients each who had to undergo a diagnostic coronary angiography. The confirmatory parameter of the study was mean erythrocyte capillary velocity [v RBC in mm/sec]. V RBC in the ipsilateral nail-fold capillaries was recorded continuously for 3 min before and 6 min after injection of RCM or isotonic saline solution in the A. axillaris respectively, and was evaluated off-line. …V RBC in nailfold capillaries was found to be decreased by Ioxaglate by 34% 150 seconds after injection, while isotonic NaCl solution immediately induced a slight increase of 14%. Show more

Keywords: Cutaneous microcirculation, Ioxaglate, coronary artery disease

DOI: 10.3233/CH-168101

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 297-304, 2016

Authors: Kehrer, Andreas | Lamby, Philipp | Miranda, Benjamin H. | Prantl, Lukas | Dolderer, Juergen H.

Article Type: Research Article

Abstract: BACKGROUND AND OBJECTIVES: Radical excisions of the rectum often result in large perineal and intrapelvic defects. Compromised wound healing can delay adjuvant therapies and limit the patient’s prognosis. With current treatment, integrity of the abdominal wall may be maintained. The defect geometry is unique and requires extensive volume for reconstruction. This study describes the surgical technique and reports clinical outcomes of fasciocutaneous posterior thigh flaps as preliminary data for this indication. METHODS: Thirteen posterior thigh flaps were used in eleven patients between 2013–2015. Patients were prospectively followed-up for the pursposes of this case series. Flap dimensions and …volume were measured in two representative cases. The surgical technique is described in detail. RESULTS: Dead space occlusion was achieved in 100% of cases. No intestinal herniation was detected. Vaginal wall defects were concurrently reconstructed in two patients. Total flap volume was calculated as 315–360 cm3 . The fasciocutaneous flaps were easy to harvest, versatile to manipulate and did not result in significant function deficits. CONCLUSIONS: In contrast to classic Vertical Rectus Abdominis Muscle (VRAM) flaps, the posterior thigh flaps preserve abdominal wall function and should be considered as a reliable alternative option in reconstruction of intrapelvic defects including neighboring organs. Future studies of larger patient series should be executed to verify our findings and determine the optimal point in time for reconstruction. Show more

Keywords: Rectum resection, rectum extirpation, pelvic defect, perineal defect, posterior thigh flap, VRAM flap

DOI: 10.3233/CH-168105

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 305-318, 2016

Authors: Mandlik, V. | Kehrer, A. | Jiga, L. | Hoinoiu, B. | Ionac, M. | Jung, F. | Staudenmaier, R. | Prantl, L.

Article Type: Research Article

Abstract: BACKGROUND: The technique of flap-prefabrication has been successfully established in tissue engineering: missing intrinsic vascularisation of engineered tissue can be generated in vivo by microsurgical vesselloop construction. It is possible to move engineered tissue into a defect with microsurgery. In the literature, the combination of engineered tissue covered with skin is not widely reported. OBJECTIVE: Aim of this study was to establish a model to investigate scaffold prefabrication with full thickness skin graft coverage with subsequent free tissue transfer. METHODS: 8 Wistar rats were operated in 2 separate steps: 1) after creating an arteriovenous …loop with the femoral vessels, a porous scaffold was placed on the loop and covered with an inguinally based skin flap. A control was implanted without loop into the contralateral groin. 2) 6 weeks later the prefabricated composite flaps were microsurgically transferred to the cervical region. Skin-island monitoring was performed with Laser Doppler-scanner after the transfer. RESULTS: Continuous loss of the skin islands was observed within 72 hours. Complications included wound-dehiscence, thrombosis and death from anaesthesia; in spite of consistent loop viability. CONCLUSION: Evaluation showed that modifications are necessary to maintain the skin-island cove. Show more

Keywords: Composite tissue, tissue engineering applications, animal models, enabling technologies, angiogenesis and vasculogenesis, fundamentals of tissue engineering

DOI: 10.3233/CH-168120

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 319-331, 2016

Authors: Bachleitner, K. | Blank, B. | Klein, S. | Geis, S. | Aung, T. | Prantl, L. | Dolderer, J.H.

Article Type: Research Article

Abstract: BACKGROUND: The reconstruction of metacarpal- and interphalangeal joints after severe hand injuries has been proven to be challenging. Commonly used procedures like arthrodesis, amputation or ray resection of the finger compromise the functionality of the injured finger. Especially for young patients, the restoration of all functions of the fingers is a priority. Local tissue transfers for finger joint reconstructions is not an option due to inacceptable donor site morbidity; microsurgical tissue transfers in terms of free toe joint transfers have proven to be a valuable method. METHODS: We present the case of a patient who suffered an …excessive injury from a circular saw to his dominant hand. The MCP Joints of D2-D4 were fully destroyed, along with the PIP joint of a subtotally amputated D4. Arteries, nerves and tendons could be coapted directly, while primarily reconstructing of the finger joints was impossible. To ensure a possible regain of full functionality, two coherent joints, the MTP and the PIP of one toe, were transferred to the ring finger as a single transplant, reconstructing the MCP and the PIP joints of the injured finger in a one step procedure. Additionally the MCP joint of the D2 was reconstructed by the use of a free PIP-joint transfer, further the MCP joint of the D3 was replaced by an MCP endoprosthesis. RESULTS: After a follow up of 3 years the patient displayed full function of his dominant hand including sensitivity, and has gone back to manual work without limitations. The result was cosmetically acceptable and the donor site defect was easily being tolerated by the patient who is playing soccer in the regional soccer league. CONCLUSION: Free double toe joint transfer has been proven feasible in this patient. While transferring a single toe joint to reconstruct a finger joint is a well-established method, our review of the latest literature showed no case of a free transfer of two coherent joints and three transplanted joints in one hand. The applied microsurgical technique should be considered by microsurgically trained hand surgeons for the treatment of comparable severe hand injuries. In comparison to the most common procedures described for the repair and reconstruction of severely injured finger joints this method showed superior results. Show more

Keywords: Free vascularized toe joint transfer, coherent double toe joint transfer, PIP-MCP-Joint-Defect, microsurgery, complex hand surgery

DOI: 10.3233/CH-168100

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 333-344, 2016