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Mackenzie IS, Hawkey CJ, Ford I, Greenlaw N, Pigazzani F, Rogers A, Struthers AD, Begg AG, Wei L, Avery AJ, Taggar JS, Walker A, Duce SL, Barr RJ, Dumbleton JS, Rooke ED, Townend JN, Ritchie LD, MacDonald TM. Allopurinol and cardiovascular outcomes in patients with ischaemic heart disease: the ALL-HEART RCT and economic evaluation. Health Technol Assess 2024; 28:1-55. [PMID: 38551218 PMCID: PMC11017142 DOI: 10.3310/attm4092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/02/2024] Open
Abstract
Background Allopurinol is a xanthine oxidase inhibitor that lowers serum uric acid and is used to prevent acute gout flares in patients with gout. Observational and small interventional studies have suggested beneficial cardiovascular effects of allopurinol. Objective To determine whether allopurinol improves major cardiovascular outcomes in patients with ischaemic heart disease. Design Prospective, randomised, open-label, blinded endpoint multicentre clinical trial. Setting Four hundred and twenty-four UK primary care practices. Participants Aged 60 years and over with ischaemic heart disease but no gout. Interventions Participants were randomised (1 : 1) using a central web-based randomisation system to receive allopurinol up to 600 mg daily that was added to usual care or to continue usual care. Main outcome measures The primary outcome was the composite of non-fatal myocardial infarction, non-fatal stroke or cardiovascular death. Secondary outcomes were non-fatal myocardial infarction, non-fatal stroke, cardiovascular death, all-cause mortality, hospitalisation for heart failure, hospitalisation for acute coronary syndrome, coronary revascularisation, hospitalisation for acute coronary syndrome or coronary revascularisation, all cardiovascular hospitalisations, quality of life and cost-effectiveness. The hazard ratio (allopurinol vs. usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis. Results From 7 February 2014 to 2 October 2017, 5937 participants were enrolled and randomised to the allopurinol arm (n = 2979) or the usual care arm (n = 2958). A total of 5721 randomised participants (2853 allopurinol; 2868 usual care) were included in the modified intention-to-treat analysis population (mean age 72.0 years; 75.5% male). There was no difference between the allopurinol and usual care arms in the primary endpoint, 314 (11.0%) participants in the allopurinol arm (2.47 events per 100 patient-years) and 325 (11.3%) in the usual care arm (2.37 events per 100 patient-years), hazard ratio 1.04 (95% confidence interval 0.89 to 1.21); p = 0.65. Two hundred and eighty-eight (10.1%) participants in the allopurinol arm and 303 (10.6%) participants in the usual care arm died, hazard ratio 1.02 (95% confidence interval 0.87 to 1.20); p = 0.77. The pre-specified health economic analysis plan was to perform a 'within trial' cost-utility analysis if there was no statistically significant difference in the primary endpoint, so NHS costs and quality-adjusted life-years were estimated over a 5-year period. The difference in costs between treatment arms was +£115 higher for allopurinol (95% confidence interval £17 to £210) with no difference in quality-adjusted life-years (95% confidence interval -0.061 to +0.060). We conclude that there is no evidence that allopurinol used in line with the study protocol is cost-effective. Limitations The results may not be generalisable to younger populations, other ethnic groups or patients with more acute ischaemic heart disease. One thousand six hundred and thirty-seven participants (57.4%) in the allopurinol arm withdrew from randomised treatment, but an on-treatment analysis gave similar results to the main analysis. Conclusions The ALL-HEART study showed that treatment with allopurinol 600 mg daily did not improve cardiovascular outcomes compared to usual care in patients with ischaemic heart disease. We conclude that allopurinol should not be recommended for the secondary prevention of cardiovascular events in patients with ischaemic heart disease but no gout. Future work The effects of allopurinol on cardiovascular outcomes in patients with ischaemic heart disease and co-existing hyperuricaemia or clinical gout could be explored in future studies. Trial registration This trial is registered as EU Clinical Trials Register (EudraCT 2013-003559-39) and ISRCTN (ISRCTN 32017426). Funding This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.
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Affiliation(s)
- Isla S Mackenzie
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | | | - Ian Ford
- The Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK
| | - Nicola Greenlaw
- The Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK
| | - Filippo Pigazzani
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | - Amy Rogers
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | - Allan D Struthers
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | - Alan G Begg
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | - Li Wei
- School of Pharmacy, University College London, London, UK
| | - Anthony J Avery
- Centre for Academic Primary Care, School of Medicine, University of Nottingham, Nottingham, UK
| | - Jaspal S Taggar
- Centre for Academic Primary Care, School of Medicine, University of Nottingham, Nottingham, UK
| | | | - Suzanne L Duce
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | - Rebecca J Barr
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | | | - Evelien D Rooke
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
| | - Jonathan N Townend
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | | | - Thomas M MacDonald
- MEMO Research, Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK
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Ye Y, Liao G, Liu T, Hu X, Chen X, Bai L, Peng Y. Allopurinol for Secondary Prevention in Patients with Cardiovascular Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Cardiovasc Dev Dis 2023; 10:379. [PMID: 37754808 PMCID: PMC10532321 DOI: 10.3390/jcdd10090379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/18/2023] [Accepted: 08/30/2023] [Indexed: 09/28/2023] Open
Abstract
BACKGROUND The effects of allopurinol in patients with cardiovascular disease are not well defined; therefore, the latest evidence is summarized in this study. METHODS PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched for randomized controlled trials (RCTs) of allopurinol in patients with cardiovascular disease published up to 11 February 2023. The primary outcome was cardiovascular death. RESULTS We combined the results of 21 RCTs that included 22,806 patients. Compared to placebo/usual care, allopurinol treatment was not associated with a significant reduction in cardiovascular death (RR 0.60; 95% CI 0.33-1.11) or all-cause death (RR 0.90; 95% CI 0.72-1.12). However, evidence from earlier trials and studies with small sample sizes indicated that allopurinol might confer a protective effect in decreasing cardiovascular death (RR 0.34; 95% CI 0.15-0.76) across patients undergoing coronary artery bypass grafting (CABG) or having acute coronary syndrome (ACS). In comparisons between allopurinol and febuxostat, we observed no difference in cardiovascular death (RR 0.92; 95% CI 0.69-1.24) or all-cause death (RR 1.02; 95% CI 0.75-1.38). CONCLUSION Allopurinol could not reduce cardiovascular (CV) death or major adverse CV outcomes significantly in patients with existing cardiovascular diseases. Given the limitations of the original studies, the potential advantages of allopurinol observed in patients undergoing CABG or presenting with ACS necessitate further confirmation through subsequent RCTs. In the comparisons between allopurinol and febuxostat, our analysis failed to uncover any marked superiority of allopurinol in reducing the risk of adverse cardiovascular incidents.
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Affiliation(s)
- Yuyang Ye
- Department of Cardiology, West China Hospital, Sichuan University, 37 Guoxue Street, Chengdu 610041, China; (Y.Y.); (G.L.); (T.L.); (X.C.); (L.B.)
| | - Guangzhi Liao
- Department of Cardiology, West China Hospital, Sichuan University, 37 Guoxue Street, Chengdu 610041, China; (Y.Y.); (G.L.); (T.L.); (X.C.); (L.B.)
| | - Ting Liu
- Department of Cardiology, West China Hospital, Sichuan University, 37 Guoxue Street, Chengdu 610041, China; (Y.Y.); (G.L.); (T.L.); (X.C.); (L.B.)
| | - Xinru Hu
- School of Medicine, Zhengzhou University, Zhengzhou 450052, China;
| | - Xuefeng Chen
- Department of Cardiology, West China Hospital, Sichuan University, 37 Guoxue Street, Chengdu 610041, China; (Y.Y.); (G.L.); (T.L.); (X.C.); (L.B.)
| | - Lin Bai
- Department of Cardiology, West China Hospital, Sichuan University, 37 Guoxue Street, Chengdu 610041, China; (Y.Y.); (G.L.); (T.L.); (X.C.); (L.B.)
| | - Yong Peng
- Department of Cardiology, West China Hospital, Sichuan University, 37 Guoxue Street, Chengdu 610041, China; (Y.Y.); (G.L.); (T.L.); (X.C.); (L.B.)
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Gelosa P, Castiglioni L, Camera M, Sironi L. Drug repurposing in cardiovascular diseases: Opportunity or hopeless dream? Biochem Pharmacol 2020; 177:113894. [DOI: 10.1016/j.bcp.2020.113894] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 02/27/2020] [Indexed: 12/14/2022]
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Ullah W, Khanal S, Khan R, Basyal B, Munir S, Minalyan A, Alraies MC, Fischman DL. Efficacy of Allopurinol in Cardiovascular Diseases: A Systematic Review and Meta-Analysis. Cardiol Res 2020; 11:226-232. [PMID: 32595807 PMCID: PMC7295562 DOI: 10.14740/cr1066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 04/17/2020] [Indexed: 11/17/2022] Open
Abstract
Background Given current evidence, the use of allopurinol for the prevention of major cardiovascular events (acute cardiovascular syndrome (ACS) or cardiovascular mortality) in patients undergoing coronary artery bypass graft (CABG), after index ACS or heart failure remains unknown. Methods Multiple databases were queried to identify studies comparing the efficacy of allopurinol in patients undergoing CABG, after ACS or heart failure. The unadjusted odds ratio (OR) was calculated using a random effect model. Results A total of nine studies comprising 850 patients (allopurinol 480, control 370) were identified. The pooled OR of periprocedural ACS (OR: 0.25, 95% confidence interval (CI): 0.06 - 0.96, P = 0.05) and cardiovascular mortality (OR: 0.22, 95% CI: 0.07 - 0.71, P = 0.01) was significantly lower in patients receiving allopurinol during CABG compared to patients in the control group. The overall number needed to treat (NNT) to prevent one ACS event was 11 (95% CI: 7 - 28), while the NNT to prevent one death was 24 (95% CI: 13 - 247). By contrast, the odds of cardiovascular mortality in the allopurinol group were not significantly different from the control group in patients on long-term allopurinol after ACS or heart failure (OR: 0.33, 95% CI: 0.01 - 8.21, P = 0.50) and (OR: 1.12, 95% CI: 0.39 - 3.20, P = 0.83), respectively. Similarly, the use of allopurinol did not reduce the odds of recurrent ACS events at 2 years (OR: 0.32, 95% CI: 0.03 - 3.18, P = 0.33). Conclusions Periprocedural use of allopurinol might be associated with a significant reduction in the odds of ACS and cardiovascular mortality in patients undergoing CABG. Allopurinol, however, offers no long-term benefits in terms of secondary prevention of ACS or mortality. Larger scale studies are needed to validate our findings.
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Affiliation(s)
- Waqas Ullah
- Abington Jefferson Health, Abington, PA, USA
| | | | - Rozi Khan
- Medstar Union Memorial Hospital, Baltimore, MD, USA
| | | | | | | | - M Chadi Alraies
- Detroit Medical Center, DMC Heart Hospital, Detroit, MI, USA
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Singh TP, Skalina T, Nour D, Murali A, Morrison S, Moxon JV, Golledge J. A meta-analysis of the efficacy of allopurinol in reducing the incidence of myocardial infarction following coronary artery bypass grafting. BMC Cardiovasc Disord 2018; 18:143. [PMID: 29996770 PMCID: PMC6042232 DOI: 10.1186/s12872-018-0881-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/03/2018] [Indexed: 01/28/2023] Open
Abstract
Background The xanthine oxidase inhibitor allopurinol that is commonly used to treat gout, has been suggested to have pleiotropic effects that are likely to reduce the incidence of myocardial infarction (MI) in at risk individuals. The aim of this meta-analysis was to assess the efficacy of allopurinol treatment in reducing the incidence of MI. Method MEDLINE, Scopus, Web of Science, and Cochrane Library databases were searched for randomised controlled trials examining the efficacy of allopurinol in reducing the incidence of MI. The quality of study methodology was assessed by two independent reviewers using the Cochrane Collaboration’s tool for assessing risk of bias. This meta-analysis was conducted using a fixed-effects model, and heterogeneity was assessed with the I2 index. Results One thousand one hundred twenty-three citations were screened and only six studies satisfied the inclusion criterion. Published between 1988 and 1995, all studies examined the cardioprotective efficacy of allopurinol in the setting of coronary artery bypass graft (CABG). From a total pooled sample size of 229, MI was reported in 2 (1.77%) allopurinol and 14 (12.07%) control patients. A fixed-effects meta-analysis (I2 = 0%) identified a statistically significant reduced incidence of myocardial infarction (RR 0.21, 95% CI: 0.06, 0.70, p = 0.01) in patients allocated to allopurinol. However, in the leave-one-out sensitivity analyses, the treatment effect became non-significant with the removal of one of the studies. Conclusion Based on the limited evidence available, allopurinol appears to reduce the incidence of perioperative MI following CABG. Further research is required to confirm these findings. Electronic supplementary material The online version of this article (10.1186/s12872-018-0881-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tejas P Singh
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia.,The Department of Vascular and Endovascular Surgery, The Townsville Hospital, Townsville, QLD, Australia
| | - Tristan Skalina
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia
| | - Daniel Nour
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia
| | - Aarya Murali
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia
| | - Sean Morrison
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia
| | - Joseph V Moxon
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia
| | - Jonathan Golledge
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD, 4811, Australia. .,The Department of Vascular and Endovascular Surgery, The Townsville Hospital, Townsville, QLD, Australia.
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Nidorf M, Jelinek M. Serendipity: How the search for meaning of serum uric acid might lead to the repurposing of an old drug in patients with cardiovascular disease. Eur J Prev Cardiol 2017; 25:231-232. [PMID: 29243514 DOI: 10.1177/2047487317749039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
| | - Michael Jelinek
- 2 Department of Medicine, University of Melbourne, Australia.,3 Department of Cardiology, St Vincent's Hospital, Melbourne, Australia
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Postconditioning with Intralipid emulsion protects against reperfusion injury in post-infarct remodeled rat hearts by activation of ROS-Akt/Erk signaling. Transl Res 2017. [PMID: 28641075 DOI: 10.1016/j.trsl.2017.05.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The clinically used lipid emulsion Intralipid (ILE) reduces ischemia reperfusion injury in healthy rodent hearts. We tested whether ILE is cardioprotective in postinfarct remodeled hearts. Post-infarct remodeled and sham Sprague-Dawley rat hearts were perfused in working mode and subjected to ischemia (15 minutes) and reperfusion (30 minutes). Left ventricular (LV) work was measured in hearts that were untreated or that received ILE (1%) postconditioning administered at the onset of reperfusion, or the reactive oxygen species (ROS) scavenger N-(2-mercaptopropionyl)-glycine (10 μM) alone or in combination with ILE. Mitochondrial O2 consumption was measured in LV muscle fibers. Acetyl CoA production was calculated from the oxidation of [U-14C]glucose and [9,10-3H]palmitate. ROS production was assessed by loss of aconitase activity as well as by release of hydrogen peroxide. Phosphorylation of Akt, Erk1/2, and STAT3 were used to evaluate protection signaling. Remodeled hearts exhibited LV dysfunction and signs of hypertrophy consistent with significant postinfarct remodeling. ILE postconditioning enhanced the recovery of postischemic LV function in remodeled hearts, preserved energy metabolism in mitochondria, accelerated palmitate oxidation and acetyl CoA production, and activated Akt/Erk/STAT3 in a ROS-dependent manner. Protection by ILE postconditioning evolved rapidly within the first minutes of reperfusion without evidence of additional cardiotonic effects due to provision of supplementary energy substrates potentially released from ILE during reperfusion. ILE represents a novel and clinically feasible cardioprotective strategy that is highly effective in remodeled hearts. Our data provide a rationale for the clinical evaluation of ILE postconditioning where ILE is administered as a bolus at the onset of reperfusion.
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Okafor ON, Farrington K, Gorog DA. Allopurinol as a therapeutic option in cardiovascular disease. Pharmacol Ther 2017; 172:139-150. [DOI: 10.1016/j.pharmthera.2016.12.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Singh P, Chauhan S, Jain G, Talwar S, Makhija N, Kiran U. Comparison of cardioprotective effects of volatile anesthetics in children undergoing ventricular septal defect closure. World J Pediatr Congenit Heart Surg 2014; 4:24-9. [PMID: 23799751 DOI: 10.1177/2150135112457580] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Volatile anesthetic agents may precondition the myocardium and protect against ischemia and infarction. Preconditioning by volatile anesthetic agents is well documented in adults but is underinvestigated in children. The present study compares the effect of preconditioning in children by three volatile anesthetic agents along with several other variables associated with cardioprotection. METHOD Eighty children scheduled for ventricular septal defect closure under cardioplegic arrest were assigned to preconditioning for five minutes after commencement of cardiopulmonary bypass (CPB) with one minimum alveolar concentration (MAC) of one of the following agents: isoflurane, sevoflurane, desflurane, or placebo (oxygen-air mixture). The plasma concentration of creatine kinase MB (CK-MB) was determined after initiation of CPB, and again 6 and 24 hours after admission to the intensive care unit (ICU) after surgery. Duration of inotropic support, mechanical ventilation, and length of ICU stay in all the groups were also recorded. RESULTS Preconditioning with isoflurane, sevoflurane, and desflurane was associated with significantly decreased postoperative release of CK-MB as compared to placebo group at 6 (group 1: 237.2 ± 189, group 2: 69.8 ± 15.8, group 3: 64.7 ± 37.8, and group 4: 70.4 ± 26.7) and 24 hours (group 1: 192.4 ± 158.2, group 2: 67.7 ± 25.0, group 3: 85.7 ± 66.8, and group 4: 50.4 ± 31.6) after admission to ICU. No significant differences were observed in the CK-MB levels among the three volatile anesthetic agents. Duration of inotropic support, mechanical ventilation, and length of ICU stay were greater in placebo group as compared to other groups without reaching statistical significance. CONCLUSION Volatile anesthetic appear to provide definite cardioprotection to pediatric myocardium. No conclusion can be drawn regarding the best preconditioning agent among isoflurane, sevoflurane, and desflurane.
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Affiliation(s)
- Pooja Singh
- Department of Cardiac Anaesthesia, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
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Qin C, Yap S, Woodman OL. Antioxidants in the prevention of myocardial ischemia/reperfusion injury. Expert Rev Clin Pharmacol 2014; 2:673-95. [DOI: 10.1586/ecp.09.41] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Bhimaraj A, Tang WHW. Role of oxidative stress in disease progression in Stage B, a pre-cursor of heart failure. Heart Fail Clin 2011; 8:101-11. [PMID: 22108730 DOI: 10.1016/j.hfc.2011.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxidative stress represents a persistent imbalance between the production and the compensation of reactive oxygen species. Though predominantly found in advanced heart failure, the most frequent "at-risk" condition has been associated with underlying oxidative stress. It is therefore conceivable that timely detection and early intervention to reduce oxidative stress processes provide an opportunity to prevent disease progression to overt heart failure. This article reviews the current understanding of the current evidence of oxidative stress involvement in the pathophysiology of human heart failure and its potential therapeutic interventions in patients with Stage A and B heart failure.
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Affiliation(s)
- Arvind Bhimaraj
- Methodist DeBakey Cardiology Associates, Smith Tower, 6550 Fannin, Suite 1901, Houston, TX 77030, USA
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George J, Struthers AD. Role of urate, xanthine oxidase and the effects of allopurinol in vascular oxidative stress. Vasc Health Risk Manag 2009; 5:265-72. [PMID: 19436671 PMCID: PMC2672460 DOI: 10.2147/vhrm.s4265] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Oxidative stress plays an important role in the progression of vascular endothelial dysfunction. The two major systems generating vascular oxidative stress are the NADPH oxidase and the xanthine oxidase pathways. Allopurinol, a xanthine oxidase inhibitor, has been in clinical use for over 40 years in the treatment of chronic gout. Allopurinol has also been shown to improve endothelial dysfunction, reduce oxidative stress burden and improve myocardial efficiency by reducing oxygen consumption in smaller mechanistic studies involving various cohorts at risk of cardiovascular events. This article aims to explain the role of xanthine oxidase in vascular oxidative stress and to explore the mechanisms by which allopurinol is thought to improve vascular and myocardial indices.
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Affiliation(s)
- Jacob George
- Division of Medicine and Therapeutics, Ninewells Hospital and Medical School, Dundee, UK.
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Lorne E, Zmijewski JW, Zhao X, Liu G, Tsuruta Y, Park YJ, Dupont H, Abraham E. Role of extracellular superoxide in neutrophil activation: interactions between xanthine oxidase and TLR4 induce proinflammatory cytokine production. Am J Physiol Cell Physiol 2008; 294:C985-93. [DOI: 10.1152/ajpcell.00454.2007] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Reactive oxygen species (ROS) contribute to neutrophil activation and the development of acute inflammatory processes in which neutrophils play a central role. However, there is only limited information concerning the mechanisms through which extracellular ROS, and particularly cell membrane-impermeable species, such as superoxide, enhance the proinflammatory properties of neutrophils. To address this issue, neutrophils were exposed to superoxide generating combinations of xanthine oxidase and hypoxanthine or lumazine. Extracellular superoxide generation induced nuclear translocation of nuclear factor-κB (NF-κB) and increased neutrophil production of the NF-κB-dependent cytokines tumor necrosis factor-α (TNF-α) and macrophage inhibitory protein-2 (MIP-2). In contrast, there were no changes in TNF-α or MIP-2 expression when neutrophils lacking Toll-like receptor-4 (TLR4) were exposed to extracellular superoxide. Immunoprecipitation, confocal microscopy, and fluorescence resonance energy transfer (FRET) studies demonstrated association between TLR4 and xanthine oxidase. Exposure of neutrophils to heparin attenuated binding of xanthine oxidase to the cell surface as well as interactions with TLR4. Heparin also decreased xanthine oxidase-induced nuclear translocation of NF-κB as well as production of proinflammatory cytokines. These results demonstrate that extracellular superoxide has proinflammatory effects on neutrophils, predominantly acting through an TLR4-dependent mechanism that enhances nuclear translocation of NF-κB and increases expression of NF-κB-dependent cytokines.
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Boueiz A, Damarla M, Hassoun PM. Xanthine oxidoreductase in respiratory and cardiovascular disorders. Am J Physiol Lung Cell Mol Physiol 2008; 294:L830-40. [PMID: 18344415 DOI: 10.1152/ajplung.00007.2008] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In addition to its critical role in purine metabolism, xanthine oxidoreductase (XOR) has been implicated in the development of tissue oxidative damage in a wide variety of respiratory and cardiovascular disorders such as acute lung injury, ischemia-reperfusion injury, atherosclerosis, heart failure, and arterial hypertension. Although much remains to be clarified about the regulation and signaling pathways of this enzyme, it is quite evident from abundant investigation in animal models and some human trials that XOR inhibition can favorably alter critical disease processes and impact outcomes. From promising bench-to-bedside data, a better understanding of this enigmatic enzyme is emerging. However, the positive findings related to XOR inhibition need to be confirmed in large-scale, well-designed clinical trials. This will hopefully provide new opportunities for therapeutic intervention. This article reviews the available evidence involving XOR in oxidative states with specific emphasis on respiratory and cardiovascular diseases.
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Affiliation(s)
- Adel Boueiz
- Division of Pulmonary and Critical Care Medicine, Dept. of Medicine, Johns Hopkins Univ. School of Medicine, 5501 Hopkins Bayview Circle, Baltimore, MD 21224, USA
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Raja SG, Dreyfus GD. Modulation of systemic inflammatory response after cardiac surgery. Asian Cardiovasc Thorac Ann 2006; 13:382-95. [PMID: 16304234 DOI: 10.1177/021849230501300422] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cardiac surgery and cardiopulmonary bypass initiate a systemic inflammatory response largely determined by blood contact with foreign surfaces and the activation of complement. It is generally accepted that cardiopulmonary bypass initiates a whole-body inflammatory reaction. The magnitude of this inflammatory reaction varies, but the persistence of any degree of inflammation may be considered potentially harmful to the cardiac patient. The development of strategies to control the inflammatory response following cardiac surgery is currently the focus of considerable research efforts. Diverse techniques including maintenance of hemodynamic stability, minimization of exposure to cardiopulmonary bypass circuitry, and pharmacologic and immunomodulatory agents have been examined in clinical studies. This article briefly reviews the current concepts of the systemic inflammatory response following cardiac surgery, and the various therapeutic strategies being used to modulate this response.
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Affiliation(s)
- Shahzad G Raja
- Department of Cardiac Surgery, Royal Hospital for Sick Children, Yorkhill NHS Trust, Dalnair Street, Glasgow G3 8SJ, Scotland, United Kingdom.
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Pacher P, Nivorozhkin A, Szabó C. Therapeutic effects of xanthine oxidase inhibitors: renaissance half a century after the discovery of allopurinol. Pharmacol Rev 2006; 58:87-114. [PMID: 16507884 PMCID: PMC2233605 DOI: 10.1124/pr.58.1.6] [Citation(s) in RCA: 791] [Impact Index Per Article: 43.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The prototypical xanthine oxidase (XO) inhibitor allopurinol, has been the cornerstone of the clinical management of gout and conditions associated with hyperuricemia for several decades. More recent data indicate that XO also plays an important role in various forms of ischemic and other types of tissue and vascular injuries, inflammatory diseases, and chronic heart failure. Allopurinol and its active metabolite oxypurinol showed considerable promise in the treatment of these conditions both in experimental animals and in small-scale human clinical trials. Although some of the beneficial effects of these compounds may be unrelated to the inhibition of the XO, the encouraging findings rekindled significant interest in the development of additional, novel series of XO inhibitors for various therapeutic indications. Here we present a critical overview of the effects of XO inhibitors in various pathophysiological conditions and also review the various emerging therapeutic strategies offered by this approach.
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Affiliation(s)
- Pál Pacher
- Laboratory of Physiological Studies, National Institute on Alcohol Aabuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane MSC 9413, Room 2N-17, Bethesda, Maryland 20892-9413, USA.
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17
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Gavin AR, Struthers AD. Hyperuricemia and adverse outcomes in cardiovascular disease: potential for therapeutic intervention. Am J Cardiovasc Drugs 2003; 3:309-14. [PMID: 14728064 DOI: 10.2165/00129784-200303050-00001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
High uric acid levels are associated with increased morbidity and mortality rates in cardiovascular disease. In this article we explore the relationship between cardiovascular disease and xanthine oxidase activity. We look at the evidence that uric acid and its production via the xanthine oxidase pathway, may directly contribute to this increased cardiovascular risk. We examine the relationship between uric acid and other established cardiovascular risk factors and look at the evidence that reducing uric acid production may have a beneficial impact on cardiovascular morbidity and mortality. We conclude that although there is currently insufficient evidence to recommend the routine use of xanthine oxidase inhibitors in those with cardiovascular disease and asymptomatic hyperuricemia, there is sufficient evidence to warrant a large scale morbidity and mortality trial.
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Affiliation(s)
- Andrew R Gavin
- Department of Clinical Pharmacology, Ninewells Hospital, Dundee DD1 9SY, Scotland
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18
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Chen T, Pan T. Variation of perioperative blood cTnT levels in patients undergoing cardiopulmonary bypass and its clinical implication. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 2002; 20:225-6. [PMID: 11215056 DOI: 10.1007/bf02886998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The clinical value of cardiac Troponin T (cTnT) as a marker in assessing myocardial cell damage in the patients undergoing open heart surgery was studied. Serum cTnT and CK-MB levels were measured in serial blood samples from 20 patients undergoing open heart surgery before operation, at aorta clamping, aorta opening, the end of CPB and the operation, and subsequently one h, one day, 3 days and one week after operation respectively. Ten patients receiving thoracic surgery were also subjected to the measurement of cTnT and CK-MB before and 24 h after operation. The results showed that peak concentrations were reached earlier in cTnT than in CK-MB, and the circulation cTnT remained high when CK-MB had already decreased to normal. In 10 patients receiving thoracic surgery, cTnT level was normal and CK-MB was increased in 4 patients after surgery. It was concluded that the sensitivity and specificity of cTnT was more than those of CK-MB and cTnT could be used as a routine indicator for myocardiac protection.
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Affiliation(s)
- T Chen
- Department of Cardiovascular and Thoracic Surgery, Tongji Hospital, Tongji Medical University, Wuhan 430030
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19
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Clancy RR, McGaurn SA, Goin JE, Hirtz DG, Norwood WI, Gaynor JW, Jacobs ML, Wernovsky G, Mahle WT, Murphy JD, Nicolson SC, Steven JM, Spray TL. Allopurinol neurocardiac protection trial in infants undergoing heart surgery using deep hypothermic circulatory arrest. Pediatrics 2001; 108:61-70. [PMID: 11433055 DOI: 10.1542/peds.108.1.61] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE This pharmacologic protection trial was conducted to test the hypothesis that allopurinol, a scavenger and inhibitor of oxygen free radical production, could reduce death, seizures, coma, and cardiac events in infants who underwent heart surgery using deep hypothermic circulatory arrest (DHCA). DESIGN This was a single center, randomized, placebo-controlled, blinded trial of allopurinol in infant heart surgery using DHCA. Enrolled infants were stratified as having hypoplastic left heart syndrome (HLHS) and all other forms of congenital heart disease (non-HLHS). Drug was administered before, during, and after surgery. Adverse events and the clinical efficacy endpoints death, seizures, coma, and cardiac events were monitored until infants were discharged from the intensive care unit or 6 weeks, whichever came first. RESULTS Between July 1992 and September 1997, 350 infants were enrolled and 348 subsequently randomized. A total of 318 infants (131 HLHS and 187 non-HLHS) underwent heart surgery using DHCA. There was a nonsignificant treatment effect for the primary efficacy endpoint analysis (death, seizures, and coma), which was consistent over the 2 strata. The addition of cardiac events to the primary endpoint resulted in a lack of consistency of treatment effect over strata, with the allopurinol treatment group experiencing fewer events (38% vs 60%) in the entire HLHS stratum, compared with the non-HLHS stratum (30% vs 27%). In HLHS surgical survivors, 40 of 47 (85%) allopurinol-treated infants did not experience any endpoint event, compared with 27 of 49 (55%) controls. There were fewer seizures-only and cardiac-only events in the allopurinol versus placebo groups. Allopurinol did not reduce efficacy endpoint events in non-HLHS infants. Treated and control infants did not differ in adverse events. CONCLUSIONS Allopurinol provided significant neurocardiac protection in higher-risk HLHS infants who underwent cardiac surgery using DHCA. No benefits were demonstrated in lower risk, non-HLHS infants, and no significant adverse events were associated with allopurinol treatment.congenital heart defects, hypoplastic left heart syndrome, induced hypothermia, ischemia-reperfusion injury, neuroprotective agents, allopurinol, xanthine oxidase, free radicals, seizures, coma.
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Affiliation(s)
- R R Clancy
- Division of Neurology, Pennsylvania, USA.
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20
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Nayak DU, Karmen C, Frishman WH, Vakili BA. Antioxidant vitamins and enzymatic and synthetic oxygen-derived free radical scavengers in the prevention and treatment of cardiovascular disease. HEART DISEASE (HAGERSTOWN, MD.) 2001; 3:28-45. [PMID: 11975768 DOI: 10.1097/00132580-200101000-00006] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Oxygen-derived free radical formation can lead to cellular injury and death. Under normal situations, the human body has a free radical scavenger system (catalase, superoxide dismutase) that can detoxify free radicals. Antioxidant vitamins and enzymatic and synthetic oxygen-derived free radical scavengers have been used clinically to prevent the formation of oxidized LDL and to prevent reperfusion injury, which is often caused by free radicals. In this article, the pathogenesis of free radical production and cell injury are discussed, and therapeutic approaches for disease prevention are presented.
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Affiliation(s)
- D U Nayak
- Department of Medicine, New York Medical College/Westchester Medical Center, Valhalla, New York, USA
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21
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Taggart DP. Biochemical assessment of myocardial injury after cardiac surgery: effects of a platelet activating factor antagonist, bilateral internal thoracic artery grafts, and coronary endarterectomy. J Thorac Cardiovasc Surg 2000; 120:651-9. [PMID: 11003744 DOI: 10.1067/mtc.2000.106325] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Platelet activating factor antagonists reduce ischemia-reperfusion injury in experiments, but there is no supportive clinical evidence. METHODS A single-center, double-blind, minimized, placebo-controlled, randomized trial of low-dose (10 mg) or high-dose (100 mg) platelet activating factor antagonist was conducted in 150 patients undergoing coronary artery bypass grafting. Myocardial injury was determined by serial measurements of the MB isoenzyme of creatine kinase and cardiac troponin T. The effects of single or bilateral internal thoracic artery grafting and coronary endarterectomy on myocardial injury were also assessed. RESULTS The placebo and platelet activating factor antagonist groups were similar with respect to preoperative, intraoperative, and postoperative factors. Four patients (2.7%) died before discharge, 3 from cardiac events. Thirteen patients (9%) had biochemical evidence of myocardial infarction, of whom 3 died. Stepwise multiple regression analysis demonstrated that duration of cardiopulmonary bypass was the most important determinant of elevations in creatine kinase MB isoenzyme and cardiac troponin T up to 6 hours after the operation and that the use of a platelet activating factor antagonist and the number of internal thoracic artery grafts did not influence myocardial injury at any time. Endarterectomy was performed in 11 patients (7%), of whom 6 (55%) had biochemically defined myocardial infarction and of whom 1 died (9%). Endarterectomy was the most important determinant of elevated levels of creatine kinase MB isoenzyme and cardiac troponin T 24 and 48 hours after the operation. CONCLUSION Platelet activating factor antagonists do not reduce perioperative myocardial injury. Bilateral and single internal thoracic artery grafting results in similar levels of myocardial injury, whereas endarterectomy is frequently associated with biochemical evidence of myocardial injury.
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Affiliation(s)
- D P Taggart
- Oxford Heart Centre, John Radcliffe Hospital, Oxford, United Kingdom.
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22
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Butler R, Morris AD, Belch JJ, Hill A, Struthers AD. Allopurinol normalizes endothelial dysfunction in type 2 diabetics with mild hypertension. Hypertension 2000; 35:746-51. [PMID: 10720589 DOI: 10.1161/01.hyp.35.3.746] [Citation(s) in RCA: 316] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Therapeutic strategies against free radicals have mostly focused on the augmentation of antioxidant defenses (eg, vitamins C and E). A novel approach is to prevent free radical generation by the enzyme system xanthine oxidase. We examined whether the inhibition of xanthine oxidase with allopurinol can improve endothelial function in subjects with type 2 diabetes and coexisting mild hypertension compared with control subjects of a similar age. We examined 23 subjects (11 patients with type 2 diabetes and 12 healthy age-matched control subjects) in 2 parallel groups. The subjects were administered 300 mg allopurinol in a randomized, placebo-controlled study in which both therapies were administered for 1 month. Endothelial function was assessed with bilateral venous occlusion plethysmography, in which the forearm blood flow responses to intra-arterial infusions of endothelium-dependent and -independent vasodilators were measured. Allopurinol significantly increased the mean forearm blood flow response to acetylcholine by 30% (3.16+/-1.21 versus 2.54+/-0.76 mL. 100 mL(-1). min(-1) allopurinol versus placebo; P=0.012, 95% CI 0.14, 1.30) but did not affect the nitroprusside response in patients with type 2 diabetes. There was no significant impact on either endothelium-dependent or -independent vascular responses in age-matched control subjects. Allopurinol improved endothelial function to near-normal levels. Regarding markers of free radical activity, the level of malondialdehyde was significantly reduced (0.30+/-0.04 versus 0. 34+/-0.05 micromol/L for allopurinol versus placebo, P=0.03) in patients with type 2 diabetes but not in control subjects. The xanthine oxidase inhibitor allopurinol improves endothelial dysfunction in patients with type 2 diabetes with mild hypertension but not in matched control subjects. In the former group, allopurinol restored endothelial function to near-normal levels.
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Affiliation(s)
- R Butler
- University Department of Clinical Pharmacology and Therapeutics, University Department of Medicine, and The Diabetes Centre, Ninewells Hospital and Medical School, Dundee, UK
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23
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Chaturvedi RR, Shore DF, Lincoln C, Mumby S, Kemp M, Brierly J, Petros A, Gutteridge JM, Hooper J, Redington AN. Acute right ventricular restrictive physiology after repair of tetralogy of Fallot: association with myocardial injury and oxidative stress. Circulation 1999; 100:1540-7. [PMID: 10510058 DOI: 10.1161/01.cir.100.14.1540] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Acute right ventricular (RV) restrictive physiology after tetralogy of Fallot repair results in low cardiac output and a prolonged stay in the intensive care unit (ICU). However, its mechanism remains uncertain. METHODS AND RESULTS In the first 24 hours after tetralogy of Fallot repair (n=11 patients), serial prospective measurements were performed of cardiac troponin T, indexes of NO production (NO(2)(-) and NO(3)(-) combined as NOx), and iron metabolism and antioxidants. RV diastolic function was assessed by transthoracic Doppler echocardiography. Patients who had a long stay in the ICU were characterized by restrictive RV physiology (nonrestrictive group [n=7]: 3.0+/-0.6 days [mean+/-SD]; restrictive group [n=4]: 10.7+/-3.1 days). Troponin T peak concentration and the area under its concentration-time curve (AUC) were higher in the restrictive RV group (peak: restrictive group 17. 0+/-2.8 microg/L, nonrestrictive group 10.4+/-4.6 microg/L, P<0.03; AUC: restrictive group 268.8+/-73.6 microg. h(-1). L(-1), nonrestrictive group 136.2+/-48.3 microg. h(-1). L(-1), P<0.03). Plasma NOx/creatinine concentrations were higher in the restrictive group than the nonrestrictive group at 2 hours after bypass (restrictive group 1.3+/-0.4, nonrestrictive group 0.8+/-0.2; P=0. 04) but were similar by 24 hours. Iron loading peaked 2 to 10 hours after bypass and was more severe in the restrictive group (peak transferrin saturation: restrictive group 83.9+/-13.0%, nonrestrictive group 58.3+/-16.2%, P=0.05; minimum total iron-binding capacity: restrictive group 0.59+/-0.21%, nonrestrictive group 0.76+/-0.06%, P=0.04; minimum iron-binding antioxidant activity to oxyorganic radicals: restrictive group 9. 5+/-22.4%, nonrestrictive group 50.6+/-11.4%, P=0.01). CONCLUSIONS After tetralogy of Fallot repair, acute restrictive RV physiology is associated with greater intraoperative myocardial injury and postoperative oxidative stress with severe iron loading of transferrin.
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Affiliation(s)
- R R Chaturvedi
- Department of Paediatric Cardiology, Royal Brompton Hospital, National Heart and Lung Institute, Imperial College of Science, Technology and Medicine, London. UK
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24
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Koh TW, Hooper J, Kemp M, Ferdinand FD, Gibson DG, Pepper JR. Intraoperative release of troponin T in coronary venous and arterial blood and its relation to recovery of left ventricular function and oxidative metabolism following coronary artery surgery. HEART (BRITISH CARDIAC SOCIETY) 1998; 80:341-8. [PMID: 9875109 PMCID: PMC1728823 DOI: 10.1136/hrt.80.4.341] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To investigate the intraoperative release of troponin T during uncomplicated coronary artery surgery and to determine its relation to ischaemic time and to recovery of left ventricular function and oxidative metabolism. DESIGN A prospective observational study. SETTING Cardiac surgical unit in a tertiary referral centre. METHODS Troponin T, creatine kinase, and lactate were analysed from arterial and coronary sinus samples taken before operation, and 1, 4, 6, 10, 20, 35, and 45 minutes after cross clamp release. Net myocardial troponin T release and lactate extraction were derived from their respective arteriovenous differences. Haemodynamic measurements were made using a thermodilution pulmonary artery catheter. PATIENTS 45 patients, mean (SD) age 62 (9) years, with two or three vessel coronary artery disease and chronic stable angina undergoing routine coronary artery surgery. RESULTS Before operation, troponin T concentrations were not raised, but within one minute of cross clamp release they increased progressively in both coronary sinus and arterial blood for the entire 45 minutes of reperfusion studied. Coronary sinus troponin T concentrations were consistently higher than arterial concentrations at all time points (p < 0.001), indicating net troponin T release by the myocardium. Peak net troponin T release and area under the curve of net troponin T release correlated closely with ischaemic time (r = 0.58 and r = 0.61, p < 0.0001 for both). Area under the curve of arterial troponin T concentration was also significantly correlated with ischaemic time (r = 0.44, p < 0.01). Patients with cross clamp times longer than 72 minutes (upper quartile for ischaemic time) had greater troponin T release, delayed reversion to lactate extraction, and lower left ventricular stroke work index three hours after surgery, compared with patients who had short (< 50 minutes, lower quartile) and intermediate (51-71 minutes, interquartile) cross clamp times. Peak net troponin T release and area under the curve of arterial troponin T concentration were inversely correlated with left ventricular stroke work index three hours after surgery (r = -0.57, r = -0.38, p < 0.01). CONCLUSIONS Troponin T concentrations increased in every patient after cross clamp release, and were consistently higher in coronary sinus blood than in arterial blood, indicating net myocardial release of troponin T during the period of reperfusion. Intraoperative net troponin T release has functional significance, as it is closely related to ischaemic time and reflects delayed recovery of left ventricular function and oxidative metabolism; therefore, its measurement may contribute to the perioperative assessment of myocardial injury sustained during coronary artery surgery.
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Affiliation(s)
- T W Koh
- Academic Department of Cardiac Surgery, Royal Brompton Hospital, London, UK
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25
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Khan F, Butler R. Free Radicals in Cardiovascular Disease. J R Coll Physicians Edinb 1998. [DOI: 10.1177/147827159802800111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- F. Khan
- Ninewells Hospital and Medical School, Dundee
| | - R. Butler
- Ninewells Hospital and Medical School, Dundee
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26
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Taggart DP, Hadjinikolas L, Hooper J, Albert J, Kemp M, Hue D, Yacoub M, Lincoln JC. Effects of age and ischemic times on biochemical evidence of myocardial injury after pediatric cardiac operations. J Thorac Cardiovasc Surg 1997; 113:728-35. [PMID: 9104982 DOI: 10.1016/s0022-5223(97)70231-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION The vulnerability of pediatric myocardium to ischemia is poorly documented in the clinical setting. METHODS Serial measurements of serum concentrations of myoglobin, the MB isoenzyme of creatine kinase, and cardiac troponins T and I and their respective areas under the curve were obtained, with particular reference to age and ischemic time, in 80 children undergoing cardiac operations. Sixteen (the control group) did not require cardiopulmonary bypass and 64 did. RESULTS In the control group there were increases (p < 0.01) in myoglobin and creatine kinase MB isoenzyme but no increase in cardiac troponin T or I; by contrast, the group treated with cardiopulmonary bypass had significant increases in all four markers but with differing temporal patterns. Younger age (especially < 12 months) was a highly significant explanatory variable only for the release of cardiac troponins T and I, and ischemic time was a significant explanatory variable for the release of creatine kinase MB isoenzyme, cardiac troponins T and I, but not myoglobin. In comparison with previous studies in adults, creatine kinase MB and cardiac troponin T concentrations were three times greater in children than in adults. CONCLUSIONS This study supports the specificity of cardiac troponins T and I as markers of myocardial injury after pediatric cardiac operations and defines the importance of age and ischemic time in determining their release. In comparison with previous data in adults, our results raise the possibility that the pediatric heart may be more vulnerable to the effects of ischemia and reperfusion. Cardiac troponins will permit comparison of new myocardial protective strategies or other potentially therapeutic myocardial interventions.
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Affiliation(s)
- D P Taggart
- Department of Cardiothoracic Surgery, Royal Brompton Hospital, London, United Kingdom
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27
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Abstract
The evaluation of myocardial damage in relation to cardiac operation from a clinical and a research perspective is of great importance, particularly for the evaluation of different cardioprotective strategies. Although measurements of serum biochemical markers have often been used, their value has been limited by their lack of sensitivity and specificity in the presence of skeletal muscle damage. A newer range of markers are now available that may reliably indicate both perioperative myocardial infarction, as well as more subtle degrees of subclinical myocyte injury. In this review, the application of biochemical markers for clinical and research purposes during cardiac operation is considered.
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Affiliation(s)
- I Birdi
- Bristol Heart Institute, University of Bristol, United Kingdom
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28
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Taggart DP, Hadjinikolas L, Wong K, Yap J, Hooper J, Kemp M, Hue D, Yacoub M, Lincoln JC. Vulnerability of paediatric myocardium to cardiac surgery. Heart 1996; 76:214-7. [PMID: 8868978 PMCID: PMC484509 DOI: 10.1136/hrt.76.3.214] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVE Myocardial injury is an important cause of mortality and morbidity after paediatric cardiac surgery. Data obtained from studies in animals imply that juvenile myocardium is more resistant to the effects of ischaemia and reperfusion than adult myocardium but there is little confirmatory evidence in the clinical setting. DESIGN Prospective observational study of biochemical markers of myocardial injury in a paediatric population undergoing cardiac surgery. SETTING Tertiary referral centre for paediatric cardiac surgery. PATIENTS Forty patients undergoing paediatric cardiac surgery of varying complexity including closure of atrial and ventricular septal defects and arterial switch for simple transposition. A control group included patients undergoing thoracotomy for closure of a patent ductus arteriosus or repair of a coarctation. INTERVENTIONS Serial measurements of myoglobin, the MB isoenzyme of creatine kinase (CK-MB), and the highly specific markers of myocardial damage cardiac troponin T (cTnT) and I (cTnI) were made before and 1, 6, 24, and 48 to 72 hours after operation. RESULTS There were significant increases in myoglobin and CK-MB, but not cTnT or cTnI, in the control group. There were significant increases in the four biochemical markers in all the cardiac operations but especially in the ventricular septal defect and transposition group. Increases in CK-MB and cTnT were about five times greater than those previously reported in adult patients. CONCLUSIONS (i) Cardiac troponins are more specific markers of myocardial injury in paediatric cardiac surgery than myoglobin and CK-MB. (ii) Paediatric myocardium seems to be more vulnerable to injury during cardiac surgery than adult myocardium.
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Affiliation(s)
- D P Taggart
- Department of Cardiothoracic Surgery, Royal Brompton Hospital, London
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29
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Taggart DP, Aratari C, Wong P, Paul EA, Wright JE, Atari C. Applicability of intermittent global ischemia for repeat coronary artery operations. J Thorac Cardiovasc Surg 1996; 112:501-7. [PMID: 8751519 DOI: 10.1016/s0022-5223(96)70278-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Despite the increasing popularity of cardioplegic techniques there is no consensus as to the optimal myocardial protective technique for first-time or repeat coronary artery bypass grafting. Intermittent global ischemia was used in 159 consecutive patients (142 male; 17 female) undergoing repeat coronary artery bypass grafting during a 6-year period (1987 to 1992). The median age of the patients was 60 years (90% confidence interval: 47 to 70 years) and the median interval from the first operation was 9 years (90% confidence interval: 2 to 14 years). One third of the patients required emergency (within 24 hours) or urgent (within 7 days) operations because of failure of symptoms to resolve with medical therapy. Compared with events at the initial operation there was an increased prevalence of impaired ventricular function (ejection fraction < 50%) and increased use of the internal thoracic artery (48% versus 9%). Two of 12 patients who required emergency operations died in the hospital, which resulted in an overall mortality rate at 30 days of 1%. Intraaortic balloon pump support was required in five patients (3%) and cardiac dose inotropic support in 21% of patients for up to 24 hours after operation. There was definite electrocardiographic evidence of infarction in 11 patients (7%). The mean postoperative blood loss, without aprotinin, was 627 ml (standard deviation 327 ml) and two patients required reexploration because of bleeding. Five patients had a hemiparesis (3%) and a further four patients (3%) had a mild or transient postoperative focal neurologic deficit. The median postoperative hospital stay was 9 days (90% confidence interval: 7 to 20 days) although 10% of patients required a hospital stay in excess of 21 days. No patient was lost to follow-up. The median (and interquartile range) period of follow-up was 1.6 (1 to 3) years. Eight patients died in the follow-up period, which resulted in an estimated survival of 80% at 5 years. At a mean follow-up period of 2 years (and with or without antianginal medication) 83% of patients had no or minimal angina, 12% had angina on moderate exertion, and 5% had angina on minimal exertion. In comparison with other current series of repeat coronary revascularization our results suggest that repeat coronary artery bypass grafting can be done with intermittent global ischemia with early and intermediate results at least equivalent to those obtained with cardioplegic methods.
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Affiliation(s)
- D P Taggart
- Department of Cardiac Surgery, London Chest Hospital, England
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30
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Taggart DP, Jenkins M, Hooper J, Hadjinikolas L, Kemp M, Hue D, Bennett G. Effects of short-term supplementation with coenzyme Q10 on myocardial protection during cardiac operations. Ann Thorac Surg 1996; 61:829-33. [PMID: 8619701 DOI: 10.1016/0003-4975(95)01120-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Coenzyme Q10 (CoQ10) is a naturally occurring vitamin-like substance that may have a beneficial role in ischemia-reperfusion injury. Coenzyme Q10 administered either as an additive to cardioplegia or as long-term preoperative oral supplementation has been reported to ameliorate myocardial injury after cardiac operations. METHODS To determine whether short-term supplementation with large doses of CoQ10 (600 mg in divided doses 12 hours before operation) was effective in myocardial protection, 20 patients with well-preserved left ventricular function (ejection fraction greater than 0.50) undergoing elective coronary revascularization were enrolled in a prospective, double-blind, placebo-controlled randomized trial. Serial concentrations of CoQ10, myoglobin, creatine kinase MD fraction, and cardiac troponin T were measured preoperatively and 1, 6, 24, 72, and 120 hours postoperatively. Efficacy of myocardial protection was also assessed by clinical outcome and serial changes in electrocardiographic indices. RESULTS The patient groups were similar with respect to preoperative and intraoperative characteristics. There was no significant difference in the preoperative plasma levels of CoQ10. These levels fell significantly in both groups after operation, although the magnitude of the decrease was less in the CoQ10-supplemented group (43% versus 60%). In both groups, there were significant postoperative increases in myoglobin, creatine kinase MB fraction, and cardiac troponin T. The magnitude of increases in cardiac troponin T was greater in the CoQ10-supplemented group, reaching marginal overall statistical significance (p = 0.06). CONCLUSIONS Short-term supplementation with large doses of CoQ10 does not lead to improved myocardial protection in patients undergoing coronary revascularization with well-preserved ventricular function and relatively short ischemic times.
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Affiliation(s)
- D P Taggart
- Department of Cardiothoracic Surgery, Royal Brompton Hospital, London, England
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31
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Taggart DP, Bhusari S, Hopper J, Kemp M, Magee P, Wright JE, Walesby R. Intermittent ischaemic arrest and cardioplegia in coronary artery surgery: coming full circle? Heart 1994; 72:136-9. [PMID: 7917685 PMCID: PMC1025476 DOI: 10.1136/hrt.72.2.136] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVE To compare the cardioprotective efficacy of cold crystalloid cardioplegia and intermittent ischaemic arrest in patients undergoing elective coronary artery surgery. DESIGN Prospective randomised trial. SETTING London teaching hospital. SUBJECTS 20 patients with at least moderately good left ventricular function undergoing elective coronary artery surgery by one experienced surgeon and needing at least two bypass grafts. INTERVENTIONS Patients were randomised to cold crystalloid cardioplegia or intermittent ischaemic arrest. MAIN OUTCOME MEASURES The primary determinant of the efficacy of myocardial protection was serial measurement (before and at 1, 6, 24, and 72 hours after the end of cardiopulmonary bypass) of cardiac troponin T (cTnT), a highly sensitive and specific marker of myocardial damage. RESULTS There was no significant difference in age, ejection fraction, number of grafts, bypass times, or cross clamp times between the two groups. One patient in the cardioplegia group had a perioperative infarct and was excluded from further study. In both groups there was a significant increase in cTnT, with peak concentrations being reached 6 hours after the end of cardiopulmonary bypass and remaining significantly high at 72 hours. At 6 hours the median (75% interquartile range) concentrations of cTnT were similar in both groups (1.8 (1.0-3.6) micrograms/l for cardioplegia v 1.9 (1.0-3.5) micrograms/l for intermittent ischaemic arrest). CONCLUSION This trial shows that intermittent ischaemic arrest, even without systemic cooling or venting of the left ventricle, provides a similar level of myocardial protection to cardioplegia in patients with moderate left ventricular function and short ischaemic times.
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Affiliation(s)
- D P Taggart
- Department of Cardiothoracic Surgery, London Chest Hospital
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Grech ED, Baines M, Steyn R, Faragher EB, Page RD, Fabri BM, Ramsdale DR, Rashid A. Normothermic versus hypothermic coronary bypass surgery. Lancet 1994; 343:1155-6. [PMID: 7910240 DOI: 10.1016/s0140-6736(94)90258-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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