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Effects of hyperbaric oxygen on vascular endothelial function in patients with slow coronary flow

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Abstract

Background: To improve therapy for slow coronary flow (SCF), the effects of hyperbaric oxygen (HBO) therapy on vascular endothelial function in SCF patients is the focus of this investigation. Methods: Ninety-eight patients who exhibited chest discomfort were retrospectively analyzed, and di-agnosed with SCF by coronary artery angiography at the Third Hospital of Hebei Medical University, Shijiazhuang, China from 2014 to 2016. The patients were divided into two groups according to the following treatment: HBO group (n = 48) and the control group (n = 50). Patients in the control group were administrated with conventional treatment, while those in the HBO group were administrated HBO therapy for 4 weeks in addition to conventional treatment. To evaluate the effects of HBO on vas-cular endothelial functions, plasma levels of nitric oxide (NO), calcitonin gene-related peptide (CGRP), endothelin-1 (ET-1), high sensitivity C-reactive protein (hsCRP) as well as endothelial-dependent flow-mediated vasodilation (FMD) of the brachial artery were measured in both groups before and after their respective treatments. Results: There were no significant differences in plasma levels of NO, ET-1, CGRP, hsCRP nor in FMD measurements between the two groups before treatment (p > 0.05). Moreover, the levels of all the parameters measured showed no significant changes before and after treatment in the control group. However, when comparing the control group, FMD and plasma NO and CGRP levels were significantly increased in the HBO group after treatment (p < 0.01), whereas hsCRP and ET-1 levels decreased dramatically (p < 0.001). Conclusions: The HBO treatment in addition to conventional therapy may significantly improve the vascular endothelial function in SCF patients. (Cardiol J 2018; 25, 1: 106-112).

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... These factors are considered to be biomarkers of vascular endothelial function. The ET-1 plasma concentration is the main systolic vascular factor and has been found to be noticeably increased in patients with coronary slow flow [41]. The main diastolic vascular factor, NO-and endothelium-dependent hyperpolarization-mediated digital vasodilatations, have been found to be markedly impaired in microvascular angina patients [42]. ...
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... Tambe proposed that the CSF phenomenon might be related to abnormal microcirculation in 1972 [2]. Oğuzhan Çelik et al. identified a correlation between the extent of disruption in endothelial function and the CSF level using the flowmediated dilation (FMD) method [21]. Several studies have found that the imbalance between endothelin-1 and nitric oxide in patients with CSF supports the involvement of endothelial dysfunction in CSF etiopathogenesis [22]. ...
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Acute heart attacks associated with coronary artery disease are collectively referred to as 'acute coronary syndrome' ( ACS). ACS is very common and may lead to severe complications including death. Hyperbaric oxygen therapy (HBOT) involves people breathing pure oxygen at high pressures in a specially designed chamber. It is sometimes used as a treatment to increase the supply of oxygen to the damaged heart in an attempt to reduce the area of the heart that is at risk of dying. We found some evidence that people with ACS are less likely to have major adverse cardiac events, and to have more rapid relief from their pain, if they receive hyperbaric oxygen therapy as part of their treatment. However, there is no good evidence that people are more likely to survive following HBOT. Our conclusions are based on five randomised trials (four of which included only patients with confirmed heart muscle death), and with a limited number of patients. Hyperbaric oxygen may therefore reduce the time to pain relief and the chance of adverse heart events in people with heart attack and unstable angina, but it is not clear if the risk of dying is reduced. Further research is needed.
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Slow coronary flow (SCF) in a normal coronary angiogram is a well-recognized clinical entity, but its etiopathogenesis remains unclear. However, previous studies have suggested that microvascular abnormalities and endothelial dysfunction responsible for SCF. Accordingly, we hypothesized that SCF phenomenon may be a form, at least early phase, of atherosclerosis that involve both small vessels and epicardial coronary arteries, and therefore we investigated coronary flow reserve (CFR) reflecting coronary microvascular function in patients with SCF. Twenty subjects with SCF and 15 control subjects with normal coronary flow were studied. Coronary flow was quantified according to TIMI frame count (TFC). Coronary diastolic peak flow velocities were measured at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak velocities. Demographic features, coronary risk factors, echocardiographic measurements except diastolic function parameters, and biochemical measurements were similar between the groups. CFR values were significantly lower in subjects with SCF than in the control group (1.99+/-0.38 versus 2.99+/-0.47, P<0.0001). In addition, TIMI frame count independently correlated with CFR. These findings suggest that CFR, which reflects coronary microvascular function, is impaired in patients with SCF, and corrected TFC well correlates with CFR.
Article
Ischemia-reperfusion injury (IRI) occurs following coronary artery revascularization. Reactive oxygen species (ROS) were initially thought to play a role in the pathogenesis of this injury. However, the evidence for this is inconclusive. Recent studies involving ischemic preconditioning have identified ROS as potential mediators for the cardioprotective effects observed following this technique. Furthermore, cardiac studies involving IRI and the use of hyperbaric oxygen (HBO) have demonstrated the ability of HBO to induce cardioprotection and to attenuate IRI. This review suggests the possible role for HBO as a new drug in the arena of myocardial revascularization and cellular protection. While there is mounting clinical evidence for this, a methodological understanding of HBO's cellular mechanisms of actions appears to be lacking. As such, this article attempts to draw the similarity between HBO and other protective oxidative stress mechanisms and then to speculate in an evidence-based manner its possible cellular mechanistic role as a drug via the generation of ROS.
Article
Statins improve endothelial functioning in patients with coronary artery disease and hypercholesterolemia, while substantially little is known about induced changes in myocardial microcirculation. However, although previous studies have suggested that microvascular abnormalities and endothelial dysfunction is responsible for slow coronary flow (SCF), there is no study investigating possible effects of statins on coronary microvascular function in patients with SCF. We prospectively investigated the effects of short-term lipid-lowering therapy with atorvastatin on coronary flow reserve (CFR) reflecting coronary microvascular function in patients with SCF assessed by transthoracic Doppler echocardiography (TTDE). In an open clinical trial, CFR was studied in 20 subjects with SCF. TTDE was used to assess CFR at baseline as well as after 8 weeks of atorvastatin therapy. Coronary flow was quantified according to TIMI frame count (TFC). Coronary diastolic peak flow velocities were measured at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak velocities. CFR was independently correlated with TFC. After 8 weeks of atorvastatin therapy, CFR values increased significantly (1.95 +/- 0.38 vs. 2.54 +/- 0.56, (p < 0.001). No change in hemodynamic parameters was noted during the entire study. The improvement in CFR was not correlated to the amount of lipid-lowering effect of atorvastatin. These findings suggest that short-term lipid-lowering therapy with atorvastatin improved CFR, which reflects coronary microvascular functioning in patients with SCF.
Article
The slow coronary flow (SCF) phenomenon is a coronary microvascular disorder characterized by the delayed passage of contrast in the absence of obstructive epicardial coronary disease. Recent studies showed the possible role of endothelial dysfunction, diffuse atherosclerosis and inflammation in the pathogenesis of this phenomenon. We aimed to investigate the effect of statin on myocardial perfusion in patients with SCF. The study population consisted of 97 patients with SCF. Coronary flow patterns of the cases are determined by thrombolysis in myocardial infarction (TIMI) frame count method. Single-photon emission computed tomographic myocardial perfusion imaging studies and lipid parameters of the patients were obtained before and after 6 months of simvastatin treatment period. During the study, daily single dose of 40 mg simvastatin has been given to each subject. We found a significant positive correlation between mean TIMI frame count and basal reversibility score (r = 0.84, p = 0.0001). In addition, analysis of the reversibility scores demonstrates that simvastatin treatment has significantly improved the myocardial perfusion abnormality at the end of the follow-up period. Present findings allow us to conclude that simvastatin improved myocardial perfusion in patients with SCF.
Article
The present study examined the hypothesis that cerebral ischemic tolerance induced by hyperbaric oxygen preconditioning (HBO-PC) is associated with an increase of antioxidant enzyme activity. Male Sprague-Dawley rats (250-280 g, n=74) were divided into sham, middle cerebral artery occlusion (MCAO) for 90 min, and MCAO plus HBO-PC groups. HBO-PC was conducted four times by given 100% oxygen at 2.5 atmosphere absolute (ATA), for 1 h at every 12 h interval for 2 days. At 24 h after the last HBO-PC, MCAO was performed and at 24 h after MCAO, neurological function and Nissl Staining were performed to evaluate the effect of HBO-PC. Malondialdehyde (MDA) content, activity of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) sampled from the hippocampus, ischemic penumbra or core of cortex were measured. HBO-PC decreased mortality rate, improved neurological recovery, lessened neuronal injury, reduced the level of MDA and increased the antioxidant activity of CAT and SOD. These observations demonstrated that an upregulation of the antioxidant enzyme activity by HBO preconditioning plays an important role in the generation of tolerance against brain ischemia-reperfusion injury.
The association of serum albumin with coronary slow flow
  • M Cetin
  • C Zencir
  • H Tasolar
Cetin M, Zencir C, Tasolar H, et al. The association of serum albumin with coronary slow flow. Wien Klin Wochenschr. 2014; 126(15-16): 468-473, doi:10.1007/s00508-014-0559-8, indexed in Pubmed: 24981407.
Early detection system of vascular disease and its application prospect
  • H Liu
  • H Wang
Liu H, Wang H. Early detection system of vascular disease and its application prospect. Biomed Res Int. 2016; 2016: 1723485, doi:10.1155/2016/1723485, indexed in Pubmed: 28042567.