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Circulation Journal : Official Journal... Jun 2024Abnormal coronary microcirculation is linked to poor patient prognosis, so the aim of the present study was to assess the prognostic relevance of basal microvascular...
BACKGROUND
Abnormal coronary microcirculation is linked to poor patient prognosis, so the aim of the present study was to assess the prognostic relevance of basal microvascular resistance (b-IMR) in patients without functional coronary stenosis.Methods and Results: Analyses of 226 patients who underwent intracoronary physiological assessment of the left anterior descending artery included primary endpoints of all-cause death and heart failure, as well as secondary endpoints of cardiovascular death and atherosclerotic vascular events. During a median follow-up of 2 years, there were 12 (5.3%) primary and 21 (9.3 %) secondary endpoints. The optimal b-IMR cutoff for the primary endpoints was 47.1 U. Kaplan-Meier curve analysis demonstrated worse event-free survival of the primary endpoints in patients with a b-IMR below the cutoff (χ=21.178, P<0.001). b-IMR was not significantly associated with the secondary endpoints (P=0.35). A low coronary flow reserve (CFR; <2.5) had prognostic value for both endpoints (primary endpoints: χ=11.401, P=0.001; secondary endpoints: (χ=6.015; P=0.014), and high hyperemic microvascular resistance (≥25) was associated only with the secondary endpoints (χ=4.420; P=0.036). Incorporating b-IMR into a clinical model that included CFR improved the Net Reclassification Index and Integrated Discrimination Improvement for predicting the primary endpoints (P<0.001 and P=0.034, respectively).
CONCLUSIONS
b-IMR may be a specific marker of the risk of death and heart failure in patients without functional coronary stenosis.
PubMed: 38897975
DOI: 10.1253/circj.CJ-24-0022 -
Intensive & Critical Care Nursing Jun 2024Capillary refill time (CRT) is defined as the time taken for color to return to an external capillary bed after pressure is applied to cause blanching. Recent studies... (Review)
Review
BACKGROUND
Capillary refill time (CRT) is defined as the time taken for color to return to an external capillary bed after pressure is applied to cause blanching. Recent studies demonstrated the benefits of CRT in guiding fluid therapy for sepsis. However, lack of consistency among physicians in how to perform and interpret CRT has led to a low interobserver agreement for this assessment tool, which prevents its availability in sepsis clinical settings.
OBJECTIVE
To give physicians a concise overview of CRT and explore recent evidence on its reliability and value in the management of sepsis.
RESEARCH DESIGN
A narrative review.
RESULTS
This narrative review summarizes the factors affecting CRT values, for example, age, sex, temperature, light, observation techniques, work experience, training level and differences in CRT measurement methods. The methods of reducing the variability of CRT are synthesized. Based on studies with highly reproducible CRT measurements and an excellent inter-rater concordance, we recommend the standardized CRT assessment method. The threshold of normal CRT values is discussed. The application of CRT in different phases of sepsis management is summarized.
CONCLUSIONS
Recent data confirm the value of CRT in critically ill patients. CRT should be detected by trained physicians using standardized methods and reducing the effect of ambient-related factors. Its association with severe infection, microcirculation, tissue perfusion response, organ dysfunction and adverse outcomes makes this approach a very attractive tool in sepsis. Further studies should confirm its value in the management of sepsis.
IMPLICATIONS FOR CLINICAL PRACTICE
As a simple assessment, CRT deserves more attention even though it has not been widely applied at the bedside. CRT could provide nursing staff with patient's microcirculatory status, which may help to develop individualized nursing plans and improve the patient's care quality and treatment outcomes.
PubMed: 38896965
DOI: 10.1016/j.iccn.2024.103743 -
Catheterization and Cardiovascular... Jun 2024In 5%-25% of non-ST-elevation acute coronary syndrome (NSTE-ACS) patients, coronary angiography reveals no obstructive coronary arteries (MINOCA). Coronary microvascular...
Continuous thermodilution and microvascular resistance reserve during the index procedure in acute coronary syndrome without obstructive coronary artery disease: A pilot study.
BACKGROUND
In 5%-25% of non-ST-elevation acute coronary syndrome (NSTE-ACS) patients, coronary angiography reveals no obstructive coronary arteries (MINOCA). Coronary microvascular disease (CMD) is a potential causal pathophysiological mechanism in these patients and can be diagnosed by continuous thermodilution assessment. Recently, the microvascular resistance reserve (MRR) has been introduced as a novel index to assess the vasodilatory capacity of the microcirculation. However, continuous thermodilution and MRR have never been investigated in the acute setting in MINOCA patients and invasive assessment of the microcirculation in these patients are currently lacking.
AIMS
The objectives of the study were to investigate the incidence of CMD (MRR ≤ 2.7) in patients with MINOCA and to evaluate the feasibility and safety of continuous thermodilution-based assessment during index coronary angiography in the acute setting.
METHODS
This study was a prospective, observational, pilot study investigating coronary physiology in the acute setting in MINOCA patients. Patients admitted with a diagnosis of NSTE-ACS were eligible for inclusion.
RESULTS
In total, 19 MINOCA patients were included in this analysis; the mean age was 70 ± 9 years, and 79% were females. CMD was present in 6 patients (32%). Q was significantly higher in the MRR ≤ 2.7 group compared to the MRR > 2.7 group (0.076 [0.057-0.100] vs. 0.049 [0.044-0.071] L/min, p = 0.03). R was significantly lower in the MRR ≤ 2.7 group compared to the MRR > 2.7 group (1083 [710-1510] vs. 1563 [1298-1970] WU, p = 0.04). No periprocedural complications or hemodynamic instability have occurred during continuous thermodilution assessment during the index coronary angiography.
CONCLUSION
In patients admitted for MINOCA undergoing immediate coronary angiography, continuous thermodilution assessment and MRR are feasible and safe in the acute setting, and evidence of functional CMD could be observed in one-third of the MINOCA patients.
PubMed: 38895766
DOI: 10.1002/ccd.31122 -
Diagnostics (Basel, Switzerland) Jun 2024The present study aimed to explore the clinical applicability of ultrasound super-resolution imaging (US SRI) for assessing renal microcirculation in patients with acute...
The present study aimed to explore the clinical applicability of ultrasound super-resolution imaging (US SRI) for assessing renal microcirculation in patients with acute kidney injury (AKI). A total of 62 patients with sepsis were enrolled in the present study-38 with AKI and 24 control patients-from whom renal ultrasounds and clinical data were obtained. SonoVue contrast (1.5 mL) was administered through the elbow vein and contrast-enhanced ultrasound (CEUS) images were obtained on a Mindray Resona A20 ultrasound unit for 2 min. The renal perfusion time-intensity curve (TIC) was analyzed and, after 15 min, additional images were obtained to create a microscopic blood flow map. Microvascular density (MVD) was calculated and its correlation with serum creatinine (Scr) levels was analyzed. There were significant differences in heart rate, Scr, blood urea nitrogen, urine volume at 24 h, and glomerular filtration rate between the two groups ( < 0.01), whereas other characteristics, such as renal morphology, did not differ significantly between the AKI group and control group ( > 0.05). The time to peak and mean transit times of the renal cortex in the AKI group were prolonged compared to those in the control group ( < 0.01), while the peak intensity and area under the TIC were lower than those in the control group ( < 0.05). The MVD of the renal cortex in the AKI group was lower than that in the control group (18.46 ± 5.90% vs. 44.93 ± 11.65%; < 0.01) and the MVD in the AKI group showed a negative correlation with Scr (R = -0.84; < 0.01). Based on the aforementioned results, US SRI can effectively assess renal microcirculation in patients with AKI and is a noninvasive technique for the diagnosis of AKI and quantitative evaluation of renal microcirculation.
PubMed: 38893718
DOI: 10.3390/diagnostics14111192 -
Journal of Clinical Medicine May 2024Erectile dysfunction (ED) most often has vascular etiology and usually is the earliest symptom of vascular dysfunction. The aim of this study was to evaluate vascular...
Erectile dysfunction (ED) most often has vascular etiology and usually is the earliest symptom of vascular dysfunction. The aim of this study was to evaluate vascular dysfunction with the use of the Flow-Mediated Skin Fluorescence (FMSF) technique in men with and without ED. Included were 39 men (median age 53) with ED and 40 men (median age 41.5) without ED. Medical interview, physical examination, and anthropometrical measurements were performed for all participants. The serum total testosterone, LH, and SHBG determinations were performed in patients with ED, and the Free Testosterone Index (FTI) was calculated. The FMSF technique was used to measure the microcirculatory oscillations at the baseline and to determine the flowmotion (FM) and vasomotion (VM) parameters. The Normoxia Oscillatory Index (NOI) was calculated, which represents the contribution of the endothelial (ENDO) and neurogenic (NEURO) oscillations relative to all oscillations detected at low-frequency intervals (<0.15 Hz): NOI = (ENDO + NEURO)/(ENDO + NEURO + VM). In men with ED were found significantly lower FM and VM parameters, but the NOI was significantly higher in comparison to men without ED. VM and FM correlated significantly positively with erectile function, orgasmic function, and general sexual satisfaction in the whole group and the FTI in the ED group. The thresholds of 53.5 FM (AUC = 0.7) and 8.4 VM (AUC = 0.7) were predictive values for discriminating men with ED. It was shown that the FMSF diagnostic technique may be helpful in the early diagnosis of microcirculation dysfunction due to impaired vasomotion caused by decreased testosterone activity.
PubMed: 38892921
DOI: 10.3390/jcm13113210 -
Nutrients Jun 2024Endothelial dysfunction (ED) is associated with progressive changes contributing to clinical complications related to macro- and microvascular diseases. Garlic ( L.) and... (Randomized Controlled Trial)
Randomized Controlled Trial
Endothelial dysfunction (ED) is associated with progressive changes contributing to clinical complications related to macro- and microvascular diseases. Garlic ( L.) and its organosulfur components have been related to beneficial cardiovascular effects and could improve endothelial function. The ENDOTALLIUM Study aimed to evaluate the effect of the regular consumption of encapsulated purple garlic oil on microvascular function, endothelial-related biomarkers, and the components of metabolic syndrome (MetS) in untreated subjects with cardiometabolic alterations. Fifty-two individuals with at least one MetS component were randomized (1:1) in a single-center, single-blind, placebo-controlled, parallel-group study. The participants received encapsulated purple garlic oil (n = 27) or placebo (n = 25) for five weeks. Skin microvascular peak flow during post-occlusive reactive hyperemia significantly increased in the purple garlic oil group compared to the placebo group (between-group difference [95%CI]: 15.4 [1.5 to 29.4] PU; = 0.031). Likewise, hs-CRP levels decreased in the purple garlic group compared to the control group (-1.3 [-2.5 to -0.0] mg/L; = 0.049). Furthermore, we observed a significant reduction in the mean number of MetS components in the purple garlic group after five weeks (1.7 ± 0.9 vs. 1.3 ± 1.1, = 0.021). In summary, regular consumption of encapsulated purple garlic oil significantly improved microvascular function, subclinical inflammatory status, and the overall MetS profile in a population with cardiometabolic alterations.
Topics: Humans; Metabolic Syndrome; Male; Garlic; Female; Middle Aged; Single-Blind Method; Adult; Sulfides; Allyl Compounds; Biomarkers; Plant Oils; Endothelium, Vascular; Skin; Microcirculation; Microvessels
PubMed: 38892688
DOI: 10.3390/nu16111755 -
International Journal of Molecular... May 2024Endothelial cells (ECs) line the inner surface of all blood vessels and form a barrier that facilitates the controlled transfer of nutrients and oxygen from the... (Review)
Review
Endothelial cells (ECs) line the inner surface of all blood vessels and form a barrier that facilitates the controlled transfer of nutrients and oxygen from the circulatory system to surrounding tissues. Exposed to both laminar and turbulent blood flow, ECs are continuously subject to differential mechanical stimulation. It has been well established that the shear stress associated with laminar flow (LF) is atheroprotective, while shear stress in areas with turbulent flow (TF) correlates with EC dysfunction. Moreover, ECs show metabolic adaptions to physiological changes, such as metabolic shifts from quiescence to a proliferative state during angiogenesis. The AMP-activated protein kinase (AMPK) is at the center of these phenomena. AMPK has a central role as a metabolic sensor in several cell types. Moreover, in ECs, AMPK is mechanosensitive, linking mechanosensation with metabolic adaptions. Finally, recent studies indicate that AMPK dysregulation is at the center of cardiovascular disease (CVD) and that pharmacological targeting of AMPK is a promising and novel strategy to treat CVDs such as atherosclerosis or ischemic injury. In this review, we summarize the current knowledge relevant to this topic, with a focus on shear stress-induced AMPK modulation and its consequences for vascular health and disease.
Topics: Humans; AMP-Activated Protein Kinases; Endothelial Cells; Cardiovascular Diseases; Stress, Mechanical; Animals; Mechanotransduction, Cellular
PubMed: 38892235
DOI: 10.3390/ijms25116047 -
International Journal of Molecular... May 2024The deformability of red blood cells (RBCs), expressing their ability to change their shape as a function of flow-induced shear stress, allows them to optimize oxygen...
The deformability of red blood cells (RBCs), expressing their ability to change their shape as a function of flow-induced shear stress, allows them to optimize oxygen delivery to the tissues and minimize their resistance to flow, especially in microcirculation. During physiological aging and blood storage, or under external stimulations, RBCs undergo metabolic and structural alterations, one of which is hemoglobin (Hb) redistribution between the cytosol and the membrane. Consequently, part of the Hb may attach to the cell membrane, and although this process is reversible, the increase in membrane-bound Hb (MBHb) can affect the cell's mechanical properties and deformability in particular. In the present study, we examined the correlation between the MBHb levels, determined by mass spectroscopy, and the cell deformability, determined by image analysis. Six hemoglobin subunits were found attached to the RBC membranes. The cell deformability was negatively correlated with the level of four subunits, with a highly significant inter-correlation between them. These data suggest that the decrease in RBC deformability results from Hb redistribution between the cytosol and the cell membrane and the respective Hb interaction with the cell membrane.
Topics: Humans; Erythrocyte Deformability; Erythrocyte Membrane; Hemoglobins; Erythrocytes; Protein Binding
PubMed: 38892001
DOI: 10.3390/ijms25115814 -
Lasers in Surgery and Medicine Jun 2024Under optimal conditions, afferent and efferent human skin graft microcirculation can be restored 8-12 days postgrafting. Still, the evidence about the reperfusion...
OBJECTIVES
Under optimal conditions, afferent and efferent human skin graft microcirculation can be restored 8-12 days postgrafting. Still, the evidence about the reperfusion dynamics beyond this period in a dermato-oncologic setting is scant. We aimed to characterise the reperfusion of human skin grafts over 4 weeks according to the necrosis extension (less than 20%, or 20%-50%) and anatomic location using laser speckle contrast imaging (LSCI).
METHODS
Over 16 months, all eligible adults undergoing skin grafts following skin cancer removal on the scalp, face and lower limb were enroled. Perfusion was assessed with LSCI on the wound margin (control skin) on day 0 and on the graft surface on days 7, 14, 21 and 28. Graft necrosis extension was determined on day 28.
RESULTS
Forty-seven grafts of 47 participants were analysed. Regardless of necrosis extension, graft perfusion equalled the control skin by day 7, surpassed it by day 21, and stabilised onwards. Grafts with less than 20% necrosis on the scalp and lower limb shared this reperfusion pattern and had a consistently better-perfused centre than the periphery for the first 21 days. On the face, the graft perfusion did not differ from the control skin from day 7 onwards, and there were no differences in reperfusion within the graft during the study.
CONCLUSION
Skin graft reperfusion is a protracted process that evolves differently in the graft centre and periphery, influenced by postoperative time and anatomic location. A better knowledge of this process can potentially enhance the development of strategies to induce vessel ingrowth into tissue-engineered skin substitutes.
PubMed: 38890796
DOI: 10.1002/lsm.23815 -
Echocardiography (Mount Kisco, N.Y.) Jun 2024Persistent microvascular obstruction (MVO) after successful percutaneous coronary intervention (PCI) in acute ST segment elevation myocardial infarction (STEMI) has been... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
Persistent microvascular obstruction (MVO) after successful percutaneous coronary intervention (PCI) in acute ST segment elevation myocardial infarction (STEMI) has been well-described. MVO predicts lack of recovery of left ventricular function and increased mortality. Sonothrombolysis utilizing diagnostic ultrasound induced cavitation of commercially available microbubble contrast has been effective at reducing infarct size and improving left ventricular ejection fraction (LVEF) when performed both pre- and post-PCI. However, the effectiveness of post-PCI sonothrombolysis alone after successful PCI has not been demonstrated.
METHODS
A prospective randomized controlled trial was performed in 50 consecutive consenting patients with anterior STEMI who underwent a continuous microbubble infusion immediately following successful PCI. Intermittent high mechanical index (MI) impulses were applied only in the sonthrombolysis group. Delayed enhancement magnetic resonance imaging (MRI) was performed at 48 h and again at 6-8 weeks to assess for differences in infarct size, LVEF, and MVO.
RESULTS
There were no differences between groups in age, gender, and cardiovascular risk factors. Significant (> 2 segments) MVO following successful PCI was observed in 66% of patients. Although sonothrombolysis reduced the extent of MVO acutely, there were no differences in infarct size, LVEF, or extent of MVO by MRI at 48 h. Twenty-eight patients returned for a follow up MRI at 6-8 weeks. LVEF improved only in the sonothrombolysis group (∆LVEF 7.81 ± 4.57% with sonothrombolysis vs. 1.77 ± 7.02% for low MI only, p = .011).
CONCLUSION
Post-PCI sonothrombolysis had minimal effect on reducing myocardial infarct size but improved left ventricular systolic function in patients with acute anterior wall STEMI.
Topics: Humans; Female; Male; Percutaneous Coronary Intervention; Middle Aged; Prospective Studies; Treatment Outcome; ST Elevation Myocardial Infarction; Recovery of Function; Myocardial Infarction; Microbubbles; Echocardiography; Microcirculation; Contrast Media; Aged
PubMed: 38889076
DOI: 10.1111/echo.15860