Retinal microcirculation reflects retinal perfusion abnormalities and retinal arterial structural changes at relatively early stages of various cardiovascular diseases. Our objective has been to establish reference values for major functional and structural parameters of retinal microcirculation in a randomly selected urban population sample. A total of 398 randomly selected individuals from an urban population aged 25 to 65 years, resident in Pilsen, Czech Republic, were screened for major cardiovascular risk factors. Retinal microcirculation was assessed using scanning laser Doppler flowmetry (SLDF), with data evaluable in 343 patients. Of this number, complete data were available for 256 individuals free from manifest cardiovascular disease, diabetes and drug treatment for hypertension and/or dyslipidemia, constituting the reference value population. Juxtapapillary retinal capillary blood flow has increased significantly with age whereas vessel and luminal diameters have decreased. No sex differences in retinal microcirculation parameters have been found. Therefore, reference values for retinal microcirculation parameters have been established by age groups. Unattended automated office systolic BP, after adjusting for age, correlated significantly with wall-to-lumen ratio (WLR) and wall thickness (WT). Moreover, after adjusting for age and mean BP, a positive relationship has been found between carotid femoral pulse wave velocity and WT, WLR and wall cross-sectional area, indicating the interaction between micro- and macro-vasculature. In conclusion, our study is the first to provide reference values of retinal microcirculation parameters in a random Caucasian population sample. Our results have shown that, at the population level, the first structural changes in retinal microcirculation are those in lumen diameters. Of note, a close relationship between BP and vascular remodeling of retinal arterioles and between aortic stiffness and WLR of retinal arterioles suggests an interaction between micro- and macro-vasculature.
- MeSH
- běloši MeSH
- dospělí MeSH
- krevní tlak MeSH
- laser doppler flowmetrie * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikrocirkulace * MeSH
- prediktivní hodnota testů MeSH
- průřezové studie MeSH
- rasové faktory MeSH
- referenční hodnoty MeSH
- regionální krevní průtok MeSH
- remodelace cév MeSH
- retinální cévy patofyziologie MeSH
- rychlost toku krve MeSH
- senioři MeSH
- tuhost cévní stěny MeSH
- věkové faktory MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Micro-vascular flaps have been used for the repair of challenging defects for over 45 years. The risk of failure is reported to be around 5-10% which despite medical and technical advances in recent years remains essentially unchanged. Precise, continuous, sensitive and specific monitoring together with prompt notification of vascular compromise is crucial for the success of the procedure. In this review, we provide a classification and brief description of the reported methods for monitoring the micro-vascular flap and a summary of the benefits over direct visual monitoring. Over 40 different monitoring techniques have been reported but their comparative merits are not always obvious. One looks for early detection of a flap's compromise, improved flap salvage rate and a minimal false-positive or false-negative rate. The cost-effectiveness of any method should also be considered. Direct visualisation of the flap is the method most generally used and still seems to be the simplest, cheapest and most reliable method for flap monitoring. Considering the alternatives, only implantable Doppler ultrasound probes, near infrared spectroscopy and laser Doppler flowmetry have shown any evidence of improved flap salvage rates over direct visual monitoring.
AIMS: Analysis of microvascular parameters in the retinal circulation-known to reflect those in the systemic circulation-allows us to differentiate between eutrophic and hypertrophic remodelling of small arteries. This study aimed to examine microvascular changes in patients with congestive heart failure (CHF) and reduced as well as mid-range ejection fraction. METHODS AND RESULTS: Forty subjects with CHF underwent measurement of retinal capillary flow (RCF), wall-to-lumen ratio (WLR), vessel and lumen diameter, wall thickness, and wall cross-sectional area (WCSA) of retinal arterioles of the right eye by scanning laser Doppler flowmetry (SLDF). Applying a matched pair approach, we compared this group with reference values of age-matched controls from a random sample in the population of Pilsen, Czech Republic. There was no significant difference in RCF and WLR between the groups (RCF: P = 0.513; WLR: P = 0.106). In contrast, wall thickness and WCSA, indicators of hypertrophic remodelling, were higher in CHF subjects (WT: 15.0 ± 4.2 vs. 12.7 ± 4.2 μm, P = 0.021; WCSA: 4437.6 ± 1314.5 vs. 3615.9 ± 1567.8 μm2 , P = 0.014). Similarly, vessel (109.4 ± 11.1 vs. 100.5 ± 14.4 μm, P = 0.002) and lumen diameter (79.0 ± 7.9 vs. 75.2 ± 8.5 μm, P = 0.009) were increased in CHF. CONCLUSIONS: In CHF subjects, we observed hypertrophic remodelling of retinal arterioles indicative of similar changes of small resistance arteries in the systemic circulation. Microvascular structure and function assessed by SLDF may thereby represent a useful, non-invasive method for monitoring of microvascular damage in patients with CHF and may offer innovative treatment targets for new CHF therapies.
- MeSH
- arterioly MeSH
- kapiláry MeSH
- laser doppler flowmetrie MeSH
- lidé MeSH
- retinální cévy * MeSH
- srdeční selhání * diagnóza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Pancreatic microcirculatory dysfunction emerged as a novel mechanism in the development of hypertension. However, the changes of pancreatic microcirculation profiles in hypertension remain unknown. Pancreatic microcirculatory blood distribution pattern and microvascular vasomotion of spontaneously hypertensive rats (SHRs) and Wistar Kyoto rats (WKYs) were determined by laser Doppler. Wavelet transform analysis was performed to convert micro-hemodynamic signals into time-frequency domains, based on which amplitude spectral scalograms were constructed. The amplitudes of characteristic oscillators were compared between SHRs and WKYs. The expression of eNOS was determined by immunohistochemistry, and plasma nitrite/nitrate levels were measured by Griess reaction. Additionally, endothelin-1, malondialdehyde, superoxide dismutase and interleukin-6 were determined by enzyme-linked immunosorbent assay. SHRs exhibited a lower scale blood distribution pattern with decreased average blood perfusion, frequency and amplitude. Wavelet transform spectral analysis revealed significantly reduced amplitudes of endothelial oscillators. Besides reduced expression of eNOS, the blood microcirculatory chemistry complements micro-hemodynamic profiles as demonstrated by an increase in plasma nitrite/nitrate, endothelin-1, malondialdehyde, interleukin-6 and a decrease of superoxide dismutase in SHRs. Here, we described abnormal pancreatic microcirculation profiles in SHRs, including disarranged blood distribution pattern, impaired microvascular vasomotion and reduced amplitudes of endothelial oscillators.
- MeSH
- endotelin-1 metabolismus MeSH
- hypertenze patofyziologie MeSH
- krevní tlak fyziologie MeSH
- krysa rodu rattus MeSH
- laser doppler flowmetrie metody MeSH
- mikrocirkulace MeSH
- modely nemocí na zvířatech MeSH
- oxid dusnatý metabolismus MeSH
- pankreas krevní zásobení patofyziologie MeSH
- potkani inbrední SHR MeSH
- potkani inbrední WKY MeSH
- vlnková analýza MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Background: We tested whether the level of endothelial dysfunction assessed by digital tonometry, and expressed as reactive hyperemia index (RHI), is related to occurrences of a discrepancy between fractional flow reserve (FFR) and the instantaneous wave free ratio (iFR) (ClinicalTrials.gov identifier: NCT03033810).Methods: We examined patients with coronary stenosis in the range of 40-70%, assessed by both FFR and iFR (system Philips-Volcano) for stable angina. We included consecutive patients with FFR and iFR in one native coronary artery, and who had had no previous intervention.Results: We included 138 patients. Out of those, 24 patients (17.4%) had a negative FFR (with an FFR value >0.8) and positive iFR (with a iFR value ≤0.89) - designated the FFRn/iFRp discrepancy group, and 22 patients (15.9%) had a positive FFR (≤0.8) and negative iFR (>0.89) - designated the FFRp/iFRn discrepancy. RHI was higher in the discrepancy groups compared the group without discrepancy (1.73 ± 0.79 vs. 1.48 ± 0.50, p = 0.025). However, this finding was not confirmed in multivariant logistic regression analyses. Patients with any type of discrepancy differed from the agreement group by having a higher occurrence of diabetes mellitus [9 patients (21.4%) vs. 36 patients (39.6%), p = 0.029], active smoking (23 patients or 54.8% vs. 26 patients or 28.6%, p = 0.003) and lower use of calcium channel blockers (9 patients, 21.4%, vs. 43 patients, 46.7%, p = 0.004).Conclusion: The presence of endothelial dysfunction can be associated with a discrepancy in FFR/iFR. However, RHI correlated with risk factors of atherosclerosis, not with FFR or iFR.
- MeSH
- cévní endotel patofyziologie MeSH
- cévní rezistence MeSH
- frakční průtoková rezerva myokardu * MeSH
- koronární stenóza * diagnóza patofyziologie MeSH
- laser doppler flowmetrie * přístrojové vybavení metody MeSH
- lidé MeSH
- manometrie přístrojové vybavení metody MeSH
- mikrocirkulace fyziologie MeSH
- navrhování softwaru * MeSH
- počítačové zpracování obrazu MeSH
- senioři MeSH
- software MeSH
- zobrazování myokardiální perfuze metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
Syndrom diabetické nohy znamená přítomnost patologie na noze diabetika distálně od kotníku, jedná se o závažnou a velmi obtížně léčitelnou komplikaci diabetes mellitus. Léčba musí být komplexní a musí zahrnovat odlehčení postižené končetiny, revaskularizaci v případě ischemie, antibiotickou léčbu v případě infekce, debridement a přípravu spodiny rány a volbu vhodného krytí rány. Zdá se, že rozhodujícím momentem pro zhojení diabetické ulcerace je dobře fungující mikrocirkulace. V popředí zájmu jsou tedy vedle metod nefarmakologických, jako jsou systémově účinkující hyperbarická oxygenoterapie či rheoferézní terapie a různé typy lokálních, převážně fyzikálních metod, i metody farmakologické podpory mikrocirkulace, zejména použití alprostadilu a sulodexidu.
Diabetic foot syndrome is a debilitating diabetic complication. The treatment must be complex, containing offloading of theaffected foot, revascularization procedures in presence of ischemia, antibiotic treatment if infection is present, debridement andproper wound bed preparation and optimal wound care choice. It seems that the most important role in healing process playsfunctional microcirculation. In support of microcirculation we can use non-pharmacological (hyperbaric oxygenotherapy, localphysical treatments) and pharmacological methods as alprostadile or sulodexide.
- Klíčová slova
- vakuově-kompresní terapie, rheoferézní terapie, SULODEXID, optická neinvazivní technologie,
- MeSH
- alprostadil farmakologie terapeutické užití MeSH
- cévní endotel fyziologie patologie účinky léků MeSH
- diabetická noha * diagnostické zobrazování diagnóza terapie MeSH
- diagnostické techniky a postupy klasifikace MeSH
- diosmin terapeutické užití MeSH
- glykosaminoglykany farmakologie klasifikace terapeutické užití MeSH
- hesperidin terapeutické užití MeSH
- hyperbarická oxygenace metody MeSH
- inzuliny terapeutické užití MeSH
- kombinovaná farmakoterapie MeSH
- komplikace diabetu diagnostické zobrazování diagnóza terapie MeSH
- laser doppler flowmetrie metody MeSH
- laserová terapie s nízkou intenzitou světla MeSH
- lidé MeSH
- mikrocirkulace * fyziologie účinky léků účinky záření MeSH
- mikroskopická angioskopie metody MeSH
- terapie ran pomocí řízeného podtlaku MeSH
- termografie metody MeSH
- transkutánní měření krevních plynů metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
BACKGROUND: The optimal surgical approach to reconnecting bowel ends safely after resection is of great importance. OBJECTIVES: This project is focused on assessment of the perianastomotic microcirculation quality in the short postoperative period when using three different anastomosis techniques in experimental animal. METHODS: The experimental study involved 27 young female domestic pigs divided into three subgroups of 9 animals according to each surgical method of anastomosis construction in the sigmoid colon region: by manual suture, by stapler, or by gluing. Blood microcirculation in the anastomosis region was monitored using Laser Doppler Flowmetry (LDF). Anastomosis healing was evaluated by macroscopic and histological examination. RESULTS: Evaluation of the microcirculation in the anastomosis region showed the smallest decrease in perfusion values in animals reconstructed by suturing (Δ= -38.01%). A significantly more profound drop was observed postoperatively after stapling or gluing (Δ= -52.42% and Δ= -59.53%, respectively). All performed anastomoses healed without any signs of tissue and function pathology. CONCLUSIONS: Sewing, stapling, and gluing techniques for bowel anastomosis each have a different effect on regional microcirculation during 120 min. postoperatively. Nevertheless, the final results of anastomosis healing were found without of any pathology in all experimental animals managed by above mentioned anastomotic techniques.
- MeSH
- anastomóza chirurgická metody MeSH
- kolon patologie chirurgie MeSH
- laser doppler flowmetrie metody MeSH
- lidé MeSH
- mikrocirkulace fyziologie MeSH
- pooperační období MeSH
- prasata MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND Paracrine factors secreted by adipose-derived stem cells can be captured, fractionated, and concentrated to produce therapeutic factor concentrate (TFC). The present study examined whether TFC effects could be enhanced by combining TFC with a biological matrix to provide sustained release of factors in the target region. MATERIAL AND METHODS Unilateral hind limb ischemia was induced in rabbits. Ischemic limbs were injected with either placebo control, TFC, micronized small intestinal submucosa tissue (SIS), or TFC absorbed to SIS. Blood flow in both limbs was assessed with laser Doppler perfusion imaging. Tissues harvested at Day 48 were assessed immunohistochemically for vessel density; in situ hybridization and quantitative real-time PCR were employed to determine miR-126 expression. RESULTS LDP ratios were significantly elevated, compared to placebo control, on day 28 in all treatment groups (p=0.0816, p=0.0543, p=0.0639, for groups 2-4, respectively) and on day 36 in the TFC group (p=0.0866). This effect correlated with capillary density in the SIS and TFC+SIS groups (p=0.0093 and p=0.0054, respectively, compared to placebo). A correlation was observed between miR-126 levels and LDP levels at 48 days in SIS and TFC+SIS groups. CONCLUSIONS A single bolus administration of TFC and SIS had early, transient effects on reperfusion and promotion of ischemia repair. The effects were not additive. We also discovered that TFC modulated miR-126 levels that were expressed in cell types other than endothelial cells. These data suggested that TFC, alone or in combination with SIS, may be a potent therapy for patients with CLI that are at risk of amputation.
- MeSH
- extracelulární matrix metabolismus MeSH
- ischemie genetika patologie terapie MeSH
- kmenové buňky cytologie MeSH
- končetiny krevní zásobení patologie MeSH
- králíci MeSH
- kůže patologie MeSH
- laser doppler flowmetrie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikro RNA genetika metabolismus MeSH
- mikropartikule metabolismus MeSH
- modely nemocí na zvířatech MeSH
- perfuze MeSH
- regulace genové exprese MeSH
- reperfuzní poškození patologie terapie MeSH
- střevní sliznice fyziologie MeSH
- tenké střevo fyziologie MeSH
- transplantace kmenových buněk * MeSH
- tuková tkáň cytologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Laser speckle contrast imaging (LSCI) is a noninvasive method, which uses scattered light to estimate the flow of a fluid containing scatterers. Thus, it can be especially used to estimate blood flow. Laser light is randomly scattered on the tissue and this refracted light interfere with reflected light, giving birth to laser speckle noise. As the light scatters on moving red blood cells, the speckle pattern is blurred due to the exposition time. This blurring is a function of velocity which can be estimated from the degree of blur, termed as speckle contrast. Therefore, blood cells act like contrast agent, outlining blood vessels. The simple setup, unnecessary contrast agent and unharming nature are making LSCI a popular tool for studying blood flow dynamics and vascular structure. This paper presents a new, simple experimental setup and image processing methods to treat laser speckle images aiming to estimate relative blood flow and vascular structure.
