Capability of ischemia-modified albumin to predict serious cardiac outcomes in the short term among patients with potential acute coronary syndrome

Ischemia-modified albumin in rheumatic diseases: A systematic review and meta-analysis

INTRODUCTION

The identification of novel, easily measurable disease biomarkers might enhance the diagnosis and management of patients with rheumatic diseases (RDs). We conducted a systematic review and meta-analysis of ischemia-modified albumin (IMA), a marker of oxidative stress, acidosis, and ischemia, in RD patients and healthy controls.

METHODS

We searched PubMed, Web of Science, and Scopus from inception to January 15, 2024. The risk of bias and the certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and GRADE, respectively.

RESULTS

In 20 studies investigating a total of 1188 RD patients (mean age 45 years, 64% females) and 981 healthy controls (mean age 44 years, 66% females), RD patients had significantly higher IMA concentrations when compared to controls (standard mean difference, SMD = 0.50, 95% CI: 0.18-0.83, p = .003; I2 = 92.4%, p < .001; low certainty of evidence). In subgroup analysis, the pooled SMD was significantly different in studies investigating ankylosing spondylitis (p < .001), Behçet's disease (p < .001), and rheumatoid arthritis (p = .033), but not familial Mediterranean fever (p = .48). Further associations were observed between the pooled SMD and the broad classification of autoimmune and/or autoinflammatory diseases, the study country, and the method used to measure IMA.

CONCLUSION

Our study suggests that IMA is a promising biomarker of oxidative stress, acidosis, and ischemia, as it can effectively discriminate between patients with different types of RDs and healthy controls. Our results warrant confirmation in longitudinal studies of patients with different types of RDs and different ethnicities (PROSPERO registration number: CRD42024509126).

Evaluation of Ischemic Modified Albumin Levels in Coronavirus Disease 2019-Positive and -Negative Patients with Acute Cardiac Injury

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 is the source of the global pandemic known as coronavirus disease 2019, and the disease prognosis is also linked to the prevalence of cardiac problems. In our study, we aimed to contribute to the early diagnosis and treatment of cardiac complications by evaluating ischemic modified albumin levels in adults with coronavirus disease 2019 disease.

METHODS

Our study was conducted with a total of 176 cases: group 1 (n = 70) with cardiac injury and coronavirus disease 2019 (+), group 2 (n = 57) with cardiac injury and coronavirus disease (-), and group 3 (n = 49) with healthy volunteers. The Mann-Whitney U test, the average, SD, minimum and maximum values, intergroup comparison of the results, and statistical significance were evaluated with the Pearson correlation coefficient.

RESULTS

As a result of the bilateral comparisons, ischemic modified albumin measurements of the coronavirus disease 2019 (+) and coronavirus disease 2019 (-) groups were higher than the control group (P =.006 and P =.006, respectively). There was no statistically significant difference between ischemic modified albumin measurements of coronavirus disease 2019 (+) and coronavirus disease 2019 (-) groups.

CONCLUSION

Ischemic modified albumin measurement accelerates the diagnosis and treatment process in the evaluation of cardiac injuries in coronavirus disease 2019 patients.

Association of neutrophil gelatinase associated lipocalin, ischemia modified albumin with uric acid in the etiopathogenesis of preeclampsia

Objectives

Preeclampsia is a multisystem illness that manifests in the third trimester of pregnancy after 20 weeks of gestation and is marked by proteinuria and hypertension (PE). Changes in lifestyle, such as eating a high-calorie diet and delaying delivery, have raised the likelihood of developing PE. Eclampsia, abrupt renal failure, thromboembolic episodes leading to cardiac and brain problems, pulmonary embolism, and coagulopathy associated with HELLP syndrome are a few of the complications that might follow preeclampsia in pregnant moms. The objects of this study is to estimate and correlate the levels of NGAL (neutrophil gelatinase associated lipocalin), IMA (ischemia modified albumin) and Uric acid in prreclampsia.

Methods

40 diagnosed cases of preeclampsia and 40 healthy age and gestational age matched healthy controls were included in the study. Blood samples were collected from them and serum NGAL, IMA and Uric acid levels were estimated. Estimation of NGAL (neutrophil gelatinase associated lipocalin), IMA (ischemia modified albumin) was done by commercially available ELISA kits standard spectrophotometry methods in autoanalyzer Mind ray BS300 using commercially available kits.

Results

The parameters of NGAL and IMA were significantly increased in patients with PE (p<0.001) when compared with the healthy control subjects. γ-glutamyl transferases and OPN were found in patients with ALD (p<0.001) when compared with the control subjects. OPN showed significant positive correlations with AST (r=0.76, p<0.001), ALT (r=0.64 p<0.001), ALP (r=0.68, p<0.001), and GGT (r=0.61, p<0.001).

Conclusions

The current study focuses on the roles of NGAL and IMA, two sensitive markers of kidney injury that are particularly useful in identifying widespread endothelial dysfunction. As a result, the pattern of elevated NGAL and IMA levels can be useful for diagnosis.

The effects of serum ischemia modified albumin on diagnosis of cerebral infarction and vertebral basilar artery stenosis

OBJECTIVES

Serum ischemia-modified albumin (IMA) is higher in patients with cerebral infarction (CI). In this study, we aimed at studying the association between IMA and CI.

METHODS

Patients with CI were divided to severe stenosis group and mild stenosis group according to the stenosis of vertebrobasilar artery. Digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) were used for diagnosis. Cobalt-combined with Albumin test was used to determine the serum IMA levels. Serum IMA levels in patients with CI and healthy volunteers were compared by t test. Receiver operating characteristic (ROC) curve was performed for evaluating the diagnostic efficiency of serum IMA for CI. The correlation between IMA level and the National Institute of Health Stroke Scale(NIHSS) score after treatment was analyzed.

RESULTS

Serum IMA levels in patients with CI was increased compared to healthy volunteers(P < .05). Patients in severe stenosis group had a higher serum IMA level than mild stenosis group(P < .05). Serum IMA level at admission was associated with NIHSS score on the 7th day after treatment(P < .05).

CONCLUSIONS

Serum IMA level was correlated with vertebrobasilar artery stenosis and  short-term prognosis in patients with acute CI.

Can the Addition of NT-proBNP and Glucose Measurements Improve the Prognostication of High-Sensitivity Cardiac Troponin Measurements for Patients with Suspected Acute Coronary Syndrome?

Guidelines published in 2021 have supported natriuretic peptide (NP) testing for the prognostication in patients with acute coronary syndrome (ACS) and for the diagnosis of chronic and acute heart failure (HF). Our objective was to determine if the addition of N-terminal pro B-type NP (NT-proBNP) and glucose to high-sensitivity cardiac troponin (hs-cTn) could better identify emergency department (ED) patients with potential ACS at low- and high-risk for a serious cardiovascular outcome over the next 72 h. The presentation sample in two different ED cohorts which enrolled patients with symptoms suggestive of ACS within six hours of pain onset (Cohort-1, n = 126 and Cohort-2, n = 143) that had Abbott hs-cTnI, Roche hs-cTnT, NT-proBNP and glucose were evaluated for NT-proBNP alone and combined with hs-cTn and glucose for the primary outcome (composite which included death, myocardial infarction, HF, serious arrhythmia and refractory angina) via receiver-operating characteristic (ROC) curve analyses with area under the curve (AUC) and diagnostic estimates derived. The AUC for NT-proBNP for the primary outcome was 0.68 (95% confidence interval (CI): 0.59-0.76) and 0.75 (95%CI: 0.67-0.82) in Cohort-1 and 2, respectively, with the 125 ng/L cutoff yielding a higher sensitivity (≥75%) as compared to the 300 ng/L cutoff (≥58%). Using the 125 ng/L cutoff for NT-proBNP with the published glucose and hs-cTn cutoffs for risk-stratification produced a new score (GuIDER score for Glucose, Injury and Dysfunction in the Emergency-setting for cardiovascular-Risk) and yielded higher AUCs as compared to NT-proBNP (p < 0.05). GuIDER scores of 0 and 5 using either hs-cTnI/T yielded sensitivity estimates of 100% and specificity estimates > 92% for the primary outcome. A secondary analysis assessing MI alone in the overall population (combined Cohorts 1 and 2) also achieved 100% sensitivity for MI with a GuIDER cutoff ≥ 2, ruling-out 48% (Roche) and 38% (Abbott) of the population at presentation for MI. Additional studies are needed for the GuIDER score in both the acute and ambulatory setting to further refine the utility, however, the preliminary findings reported here may present a pathway forward for inclusion of NP testing for ruling-out serious cardiac events and MI in the emergency setting.

Correlation IMA with TIMI frame count in slow coronary flow: can it be a guide for treatment?

AIM

Coronary slow flow (CSF) is defined as late opacification in epicardial coronary arteries with no significant stenosis. The aim of this study is to evaluate the relationship between ischemia-modified albumin (IMA) by using Spectrophotometer in CSF.

METHODS

Level of IMA was measured by spectrophotometer. CSF patients were chosen for the determination of IMA level. All obtained data were compared with control groups.

RESULTS

Serum IMA levels increased in the CSF group. It was observed that there was a significant increase in IMA levels in patients with CSF when compared to controls (p < 0.05).

CONCLUSION

IMA may play a role in the pathogenesis of CSF. IMA levels in the serum can be considered as a marker to predict coronary slow flow. IMA level can be used as a guide for coronary slow flow. Also, as increases number square frame, value IMA Increases similarly. It was found that the severity of impotence was correlated with CSF. Therefore, the IMA level may be predictive of the course of treatment. This study is the first one to show the relationships of IMA in CSF. In addition, further studies should be performed on IMA in CSF patients.

The evaluation of thiol-disulfıte balance, ischemıa albumın modıfıcation and seruloplazmine as a new oxidatıve stress in mild cognitive impairment and early stage alzheimer's disease patients

BACKGROUND

Alzheimer's Disease (AD) is the most common form of dementia seen in advanced age. It is characterized by progressive deterioration in cognitive functions. The prevalence of Alzheimer's disease increasing day by day due to the increase in the share of the elderly population in the general population due to developing health and living conditions, is limited and early diagnosis and effective treatment possibilities are very limited. From this point of view, a specific biomarker for AD is very important. As a new oxidative stress biomarker, the levels of thiol-disulfide balance, ischemia-modified albumin and seroloplazminin were evaluated. The aim of this study was to determine the serum levels of oxidative stress biomarkers in the early stages of the disease and to compare these oxidative stress markers with patients with mild cognitive impairment as a precursor form of Alzheimer's disease and to determine whether these markers develop at an earlier stage.

METHODS

30 volunteers with early stage AD according to NINCDS-ARDRA criteria, 19 volunteers with Midl Cognitive İmpairment according to PCA criteria and 30 volunteers with defined criteria were selected from the subjects aged between 55 and 88 who applied to Gazi University Health Research. Statistical analysis of the data showed that there was a significant difference between the endgroups and biomarkers for the early diagnosis of Alzheimer's disease, but this complicated matter has to be investigated in more comprehensive and detailed studie.

RESULTS

In the present study, we investigated oxidative stress parameters, thiol-disulphide balance, ischemia modified abumin and seruloplasmin in parallel with the impairment in cognitive dysfunction from control group to Mild Cognitive Impairment (MCD) and AD group by using a newly-developed method.

CONCLUSIONS

This is the first study in literature comparing Early Stages Alzheimer Disease (ESAD), MCD and healthy volunteer groups. Our study has revealed that these newly developed tests may be candidates as oxidative stress biomarkers in pathgenesis of AD. However it was concluded that more comprehensive and detailed studies are required to enlighten this issue.

Ischemia-Modified Albumin, a Novel Predictive Marker of In-Hospital Mortality in Acute Aortic Dissection Patients

Background

This work explored the prognostic prediction capabilities of ischemia-modified albumin (IMA) in patients suffering from acute aortic dissection (AAD).

Methods

We conducted a retrospective analysis using electronic health records. This study included AAD patients admitted to the Second Xiangya Hospital of Central South University from January 2015 to December 2018 in ≤24 h from the onset of symptoms to hospital admission. The levels of IMA were recorded upon admittance and the final was the all-cause mortality during hospitalization.

Results

This study enrolled 731 AAD patients. Among who, 160 passed away in the course of medication while 571 of them survived. Those who passed away exhibited higher levels of IMA (94.35 ± 26.84 vs. 69.14 ± 14.70, p < 0.001) than the survivors. Following the adjustment confounders, the fully adjusted model showed IMA to be an independent forecastor for in-hospital mortality for AAD patients (OR 1.10, 95% CI 1.08–1.13, p < 0.001). Analysis based on receiver operating characteristic (ROC) revealed that 79.35 μ/ml was the best threshold of IMA level. The area under the curve (AUC) based on this IMA level was 0.854 (95% CI 0.822–0.898) while the specificity and sensitivity to anticipate in-hospital death were 84.8 and 80.6%, respectively.

Conclusion

Admission IMA was an independent forecastor for in-hospital mortality among people suffering from AAD.

Profiling thiol metabolites in myocardial infarction human serum by stable isotope labeling assisted liquid chromatography-mass spectrometry

Myocardial Infarction (MI) is one of the most common causes of deaths worldwide. Thiols have been reported to play a key role in physiological and pathological processes of MI. Comprehensive analysis of thiols would be conducive to fully elucidate the relation between thiols and MI. In the current study, we analyze the metabolomic differences of thiols in serum between MI patients (n = 30) and healthy controls (HCs, n = 30) by stable isotope labeling-dispersive solid phase extraction-liquid chromatography-full scan-Orbitrap-mass spectrometry analysis (IL-DSPE-LC-full scan-Orbitrap MS) method. We detected 300 potential thiols in serum of MI patients and HCs, among which, 67 thiols were positively or putatively identified. Furthermore, we found that the levels of 71 thiols in serum exhibited significant difference between MI patients and HCs. In the transsulfuration pathway, we observed that Cys and Hcys were upregulated, while GSH were downregulated. Our results provide a comprehensive understanding of thiols metabolome in human serum between MI patients and HCs.

Status of Ischemia Modified Albumin in Athletes Before and After Moderate Exercise

Background:

Ischemia Modified Albumin (IMA) is considered as an early marker of ischemia. Its levels may be altered in any clinical condition where an ischemic event is involved. Skeletal muscle ischemia is associated with severe exercise but may also occur in moderate form of exercise.

Objective:

The levels of IMA were estimated before and after thirty minutes of moderate exercise in students undergoing athletic training.

Methods:

The present study was conducted on 120 young adult students undergoing athletic training program in the physical education department. All the subjects were healthy with normal body mass index and blood pressure. Their serum samples were collected before and after running for half an hour on the racing track and were analyzed for IMA colorimetrically and the data was subjected to appropriate statistical analysis.

Results:

The levels of IMA were found to be statistically significantly higher after exercise as compared to those before exercise (p = 0.005). The ratio of IMA to albumin (IMAR) was also found to be significantly higher after exercise as compared to that before exercise (p=0.000).

Conclusion:

It may be concluded that the skeletal muscle ischemia induced by moderate aerobic exercise is associated with an increased conversion of albumin to IMA.

Evaluation of the Siemens ADVIA Centaur high-sensitivity cardiac troponin I assay in serum

BACKGROUND

International recommendations on high-sensitivity cardiac troponin (hs-cTn) testing recommend that laboratories select only one sample type for testing. We evaluated the Siemens ADVIA Centaur hs-cTnI assay in serum and thereby provide information on imprecision, long-term storage stability, freeze-thaw stability, method comparison to other hs-cTnI assays, and clinical performance.

METHODS

Patients with chest pain onset <6 h who already had Roche hs-cTnT, Beckman hs-cTnI and Abbott hs-cTnI results recorded and had non-thawed and frozen serum aliquots formed the study population (n = 134 patients with 305 serum aliquots obtained at either 0, 3 or 6 h stored below -70 °C since 2003) for measurement with the Siemens hs-cTnI assay in 2018. Receiver-operating characteristic curve analyses for myocardial infarction (MI) using the highest obtained hs-cTn concentration was performed. Additional comparison testing on serum samples stored frozen (at -70 °C for <1 month in 2018) for the Siemens and Abbott hs-cTnI assays were performed, as well as precision testing in serum pools and freeze-thaw stability testing.

RESULTS

The Siemens hs-cTnI assay had an area under the curve (AUC) of 0.978 (95%CI: 0.937-0.996) for MI in the study cohort (Roche hs-cTnT AUC = 0.965 and Abbott AUC = 0.973). The Siemens hs-cTnI assay yielded higher cTnI concentrations than the other hs-cTn assays, with the same proportional bias (slope = 1.4) between the Siemens and Abbott hs-cTnI assays obtained from serum samples collected in 2003 and 2018. Over 3 months, a low serum pool of 3.5 ng/l achieved a CV of 20% (SD = 0.7, n = 42) and a high serum pool of 820 ng/l achieved a CV of 2.3% (SD = 20, n = 42). Three different serum pools recovered within 10% from baseline concentration after 5 freeze-thaw cycles for the Siemens hs-cTnI assay.

CONCLUSIONS

In serum, the Siemens ADVIA Centaur hs-cTnI assay had excellent clinical performance for MI in an early chest pain onset population, acceptable precision at normal and highly elevated cTnI concentrations, long-term storage stability (15 y storage below -70 °C) and acceptable freeze-thaw stability, all of which supports serum as an acceptable sample type to use in clinical studies and in clinical practice.

The Collocation of Ischemia-Modified Albumin and Blood Gas Parameters in the PICU Setting

Ischemia modified albumin (IMA) is a marker that has been determined to be elevated in hypoxic conditions. This study aimed to investigate the relationships between serum IMA and blood gas parameters (BGPs) and evaluate whether IMA can be used as a parameter clinically in terms of reflecting tissue hypoxia in ventilator management. BGPs and serum IMA level were measured in blood samples drawn simultaneously from patients. Mean serum IMA levels, mean pCO₂, mean pO₂, and lactate levels were 82.56 ± 25.47 ng/mL, 47.99 ± 22.81 mm Hg, 53.62 ± 30.43 mm Hg, and 2.13 ± 3.22 mmol/L, respectively. No correlation was found between serum IMA level and BGPs. Our findings showed that serum IMA level can be concluded not to be a suitable parameter in ventilator management. However, IMA can be a reliable guide if used together with venous BGPs in terms of the estimating of tissue oxygenation, especially within the last few hours.

The Effect of the Antioxidant Drug U-74389G on Albumin Levels during Ischemia Reperfusion Injury in Rats

This experimental study examined the effect of the antioxidant drug U-74389G on a rat model and particularly in a liver ischemia - reperfusion protocol. The effects of that molecule were studied biochemically using blood mean albumin levels. 40 rats of mean weight 231.875 g were used in the study. Albumin levels were measured at 60th min of reperfusion (groups A and C) and at 120th min of reperfusion (groups B and D). The drug U-74389G was administered only in groups C and D. U-74389G administration significantly decreased the predicted albumin levels by 3.63% ± 0.87% (p = 0.0001). Reperfusion time non-significantly increased the predicted albumin levels by 0.72% ± 1.04% (p = 0.4103). However, U-74389G administration and reperfusion time together significantly decreased the predicted albumin levels by 2.02% ± 0.54% (p = 0.0005). U-74389G administration whether it interacted or not with reperfusion time has significant decreasing short - term effects on albumin levels. It seems that the antioxidant capacity is associated with albumin catabolism.

Role of "Ischemia Modified Albumin" (IMA) in acute coronary syndromes

BACKGROUND

Diagnosis of acute coronary syndrome (ACS) is important, due to the associated very high mortality. Failure to diagnose ACS is a problem both for the patients and the clinicians. Ischemia modified albumin (IMA) has already been licensed by the US Food and Drug Administration for the diagnosis of suspected myocardial ischemia.

METHODS

Patients attending the emergency department (ED) within 6 h after having features of ACS were selected. IMA was done on admission. Blinded to the IMA results patients were fully evaluated and a diagnosis of non-ischemic chest pain (NICP), unstable angina (UA) or myocardial infarction (MI) was made. Later IMA results were correlated in each group.

RESULTS

Mean IMA value was 56.38 ± 23.89 u/ml in NICP group whereas in UA group it was 89.00 ± 7.76 u/ml and MI group was 87.50 ± 9.62 u/ml. This showed a sensitivity of 92% and specificity of 87%. The positive predictive value of the test was 88% and negative predictive value was 94%. In 16 patients an early diagnosis could be made when compared with Trop-T. Of the 89 patients 11 patients died in hospital. The IMA value was compared between this group and the patients who survived. Patients who died had a mean IMA value of 88.5 with a standard deviation of 5.33 whereas in patients who survived the mean value was 78.26 which was not statistically significant.

CONCLUSION

In conclusion the benefit of the test would be to rule out ACS in patients who present early to ED with inconclusive diagnosis.

Serum ischemia-modified albumin levels in children with epileptic seizures

OBJECTIVES

The aim of the present study was to determine the level of ischemia-modified albumin (IMA) in children with epileptic seizures (ESs) and its relation with the seizure duration.

METHODS

The study was performed with 88 children as a prospective case-control study. Blood samples for IMA were obtained from 57 patients (mean age [SD], 50.86 [51.15] months) within 3 hours after ES and 31 healthy control subjects (mean age [SD], 53.13 [40.87] months). Ischemia-modified albumin was measured by the albumin cobalt binding test.

RESULTS

Although the mean (SD) of serum IMA level of the patients with seizure was 13.66 (13.16) U/mL, the mean (SD) of serum IMA level for the control group was 3.73 (1.93) U/mL. Ischemia-modified albumin levels were significantly higher in patients with seizure, compared with that in the control group (P < 0.01). When patients were grouped in itself according to the duration of ESs, the levels of IMA were detected to be increased in patients as the duration of seizures was lengthened.

CONCLUSIONS

Increased IMA levels after seizures suggest that IMA assay during seizure may be useful for predicting the diagnosis and severity of convulsion.

Biomarkers for Predicting Serious Cardiac Outcomes at 72 Hours in Patients Presenting Early after Chest Pain Onset with Symptoms of Acute Coronary Syndromes

BACKGROUND

Most outcome studies of patients presenting early to the emergency department with potential acute coronary syndromes have focused on either the index diagnosis of myocardial infarction (MI) or a composite end point at a later time frame (30 days or 1 year). We investigated the performance of 9 biomarkers for an early serious outcome.

METHODS

Patients (n = 186) who presented to the emergency department within 6 h of chest pain onset had their presentation serum sample measured for the following analytes: creatine kinase, creatine kinase isoenzyme MB, enhanced AccuTnI troponin I (Beckman Coulter), high-sensitivity cardiac troponin T (hs-cTnT), ischemia-modified albumin, interleukin-6, investigation use only hs-cTnI (Beckman Coulter), N-terminal pro–B-type natriuretic peptide, and cardiac troponin I (Abbott AxSym). We followed patients until 72 h after presentation and determined whether they experienced the following serious cardiac outcomes: MI, heart failure, serious arrhythmia, refractory ischemic cardiac pain, or death. ROC curves were analyzed to determine the area under the ROC curve (AUC) and optimal cutoffs for the biomarkers.

RESULTS

The AUCs for the hs-cTnI assay (0.86; 95% CI, 0.76–0.96), the AccuTnI assay (0.86; 95% CI, 0.78–0.95), and the hs-cTnT assay (0.82; 95% CI, 0.71–0.94) assays were significantly higher than those for the other 6 assays (AUC values ≤0.71 for the rest of the biomarkers, P &lt; 0.05). The ROC curve–derived optimal cutoffs were ≥19 ng/L (diagnostic sensitivity, 80%; specificity, 88%), ≥0.018 μg/L (diagnostic sensitivity, 75%; specificity, 86%), and ≥32 ng/L (diagnostic sensitivity, 68%; specificity, 92%) for the hs-cTnI, AccuTnI, and hs-cTnT assays, respectively.

CONCLUSIONS

The optimal cutoffs for predicting serious cardiac outcomes in this low-risk population are different from the published 99th percentiles. Larger studies are required to verify these findings.

Current role of ischemia-modified albumin in routine clinical practice

BACKGROUND

Ischemia-modified albumin has been proposed as a useful rule-out marker for the diagnosis of acute coronary syndrome in the emergency department.

OBJECTIVE

To perform a review of ischemia-modified albumin use in the clinical practice.

METHODS

We performed a comprehensive literature search by using electronic bibliographic databases.

CONCLUSION

Although the main limitation of ischemia-modified albumin at present is its low specificity, it may be a useful test to rule out acute coronary syndrome from low to moderate pre-test probability conditions with negative cardiac troponins and a negative ECG.

Ischemia-modified albumin levels predict long-term outcome in patients with acute myocardial infarction. The French Nationwide OPERA study

BACKGROUND

Little is known about the capacity of ischemia-modified albumin (IMA) plasma concentration to predict long-term cardiac outcome in patients with established acute myocardial infarction (AMI). Because IMA is a marker of ischemia rather than myocardial cell damage, we hypothesized that IMA plasma levels could provide additional prognostic value to classic clinical and biological risk markers in patients with AMI. Therefore, we investigated the predictive value of plasma IMA in patients with AMI enrolled in the French Nationwide OPERA study.

METHODS

Plasma concentrations of IMA and other cardiac biomarkers (troponin, C-reactive protein, B-type natriuretic peptide) were measured within 24 hours of hospital admission in 471 patients hospitalized with an AMI (defined using European Society of Cardiology/American College of Cardiology criteria). Patients' characteristics, cardiovascular risk factors and treatments, and clinical outcomes were recorded. Univariate and multivariable predictors of cardiac outcome in-hospital and at 1 year were identified.

RESULTS

The primary composite end point (death, resuscitated cardiac arrest, recurrent myocardial infarction or ischemia, heart failure, stroke) occurred in 75 (15.6%) patients in-hospital and in 144 (30.6%) at 1 year: 40% of patients in the highest IMA quartile (>104 IU/mL) reached the end point compared with 20% in the lowest (<83 IU/mL) by 1 year. Multivariable logistic regression analysis identified 4 independent predictors of composite end point at 1 year: plasma concentrations of IMA (P = .01), brain natriuretic peptide (P = .001), heart failure (P = .005), and age (P = .003).

CONCLUSIONS

In patients with AMI, IMA measured within 24 hours is a strong and independent predictor of cardiac outcome at 1 year and may help identify those requiring more aggressive medical management.

Diagnostic value of ischemia-modified albumin in patients with suspected acute coronary syndrome

INTRODUCTION

Ischemia-modified albumin (IMA) has been proposed as a useful rule-out marker for the diagnosis of acute coronary syndrome (ACS) in the emergency department. This study evaluated the ability of IMA to predict the acute myocardial infarction (AMI) diagnosis in a population of chest pain patients.

METHODS

The study population comprised 107 subjects (men, 62%; women, 38%) admitted with suspected ACS. None of the patients had ST-segment elevations that qualified for immediate revascularization. Ischemia-modified albumin was determined from serum with albumin cobalt binding test (Inverness Medical Innovations Inc, Stirling, UK). Furthermore, cardiac troponin T, creatinine kinase MB mass, myoglobin, and heart-type fatty acid binding protein (H-FABP) were determined on arrival, after 6 to 9 hours, and after 12 to 24 hours. All patients had at least 2 blood samples taken to exclude/verify the AMI. AMI was defined by a cardiac troponin T level greater than 0.03 microg/L.

RESULTS

Thirty-three percent of the patients (n = 35) had a final diagnosis of AMI. The sensitivity of admission IMA for a final diagnosis of ACS was 0.86 (95% confidence interval [95% CI], 0.69-0.95). Specificity was 0.49 (95% CI, 0.36-0.60). Negative predictive value was 0.88 (95% CI, 0.72-0.95). The optimal cutoff threshold derived from the receiver operating characteristics (ROC) curve (ROC analysis) was determined as 91 U/mL. The area under the ROC curve was 0.73. Ischemia-modified albumin did not, at any time, provide superior sensitivity or specificity compared with other biomarkers. We do not find the data supportive of IMA as a standard marker in the emergency department.

Ischemia modified albumin: a novel biomarker for the detection of cardiac ischemia

SUMMARY

The diagnosis of cardiac ischemia remains a challenge in contemporary emergency medicine. A blood-borne biomarker is an attractive alternative to cardiac imaging or stress testing as it would be cheaper and logistically faster to obtain. A number of candidate biomarkers have been proposed for the detection of cardiac ischemia; however, only Ischemia Modified Albumin (IMA) has been released for clinical use. IMA is a good discriminator between ischemic and non-ischemic patients. Changes in IMA concentration have shown to occur during coronary angioplasty-induced ischemia. Clinical studies indicate that IMA appears to offer on admission an early test which can be combined with electrocardiographic findings and cardiac troponin measurements for the early exclusion of acute coronary syndrome. IMA is an independent predictor of short and long term adverse outcomes in patients with acute chest pain. However, this test is relatively new and uncertainties remain. Elevations of IMA occur in conditions other than chest pain, thus questioning its specificity. The mechanism of IMA formation and the precise entity being measured are not fully known. Nevertheless, IMA measurement remains the only current clinical biomarker which may be used for the diagnosis of patients suspected of cardiac ischemia.

Derivation and validation of a sensitive IMA cutpoint to predict cardiac events in patients with chest pain

OBJECTIVES

In patients with acute chest pain, we derived a cutpoint for ischaemia-modified albumin (IMA) and prospectively validated this cutpoint to predict 30-day major adverse cardiac events (MACEs).

METHODS

We prospectively recruited a derivation cohort (18-month period) to establish a serum IMA cutpoint targeting 80% sensitivity. This was followed by a prospective validation cohort study of emergency department patients with acute chest pain at two university hospitals over a 3-month period. A MACE was defined as myocardial infarction, revascularisation or death at 30-day follow-up.

RESULTS

In the derivation cohort of 151 patients, the IMA cutpoint that achieved 80% sensitivity for MACEs was 75 KU/litre. The sensitivity was prospectively validated in 171 patients consecutively enrolled, of whom 106 underwent multiple-biomarker analysis (19.8% MACE rate, 81% sensitivity of IMA). Furthermore, IMA by itself (81%, p<0.01) and in combination with initial highly sensitive cardiac troponin T (hsTnT) (90%, p<0.001) had significantly higher sensitivity than initial hsTnT (29%) for prediction of MACEs.

CONCLUSIONS

We prospectively validated the sensitive IMA cutpoint of 75 KU/litre with 80% sensitivity for MACEs in patients with acute chest pain. Our data suggest that IMA alone and in combination with initial hsTnT are more sensitive than the initial hsTnT for MACEs.

PAPP-A as a marker of increased long-term risk in patients with chest pain

OBJECTIVES

Long-term risk stratification in patients presenting with acute coronary syndromes (ACS) is possible by measuring cardiac troponin (cTn). The present study examined whether PAPP-A measured in an emergency department (ED) chest pain population in association with conventional and novel high sensitivity cTn (hs-cTnI) assays can predict long-term mortality.

METHODS

In 320 patients with cTn measurements the earliest heparinized plasma PAPP-A concentration after presentation was used for risk stratification for death by Kaplan-Meier and Cox analyses. Subgroup analyses using the earliest PAPP-A concentrations were also performed in a cohort of subjects with presentation cTnI < or = 99th percentile but with significantly changing cardiac troponin concentrations as measured by the AccuTnI assay and the hs-cTnI assay (n=45 and 120 subjects, respectively).

RESULTS

Subjects with PAPP-A concentrations in the highest tertile were at higher risk for death (HR > 2.00; p < or = 0.05 at 2 years) even after adjusting for cTnI at presentation. In the cohort with cTnI < or = 99th percentile but with changing hs-cTnI concentrations, subjects in the top PAPP-A tertile had a higher probability for death (p=0.02).

CONCLUSION

Early measurement of PAPP-A may identify chest pain patients at higher risk for long-term death. Additional prospective ACS studies are required to fully elucidate PAPP-A's role.

Biomarkers in Acute Coronary Syndrome

BACKGROUND: Evaluation of patients who present to the hospital with acute undifferentiated chest pain or other symptoms and signs suggestive of Acute Coronary Syndrome (ACS) is often a clinical challenge. The initial assessment, requiring a focused history (including risk factors analysis), a physical examination, an electrocardiogram (EKG) and serum cardiac marker determination, is time-consuming and troublesome. Recent investigations have indicated that increases in biomarkers of necrosis, inflammation, ischemia and myocardial stretch may provide earlier assessment of overall patient risk, help in identifying the adequate diagnostic and therapeutic management for each patient and allow for prevention of substantial numbers of new events. APPROACH AND CONTENT: The purpose of this review is to provide an overview of the characteristics of several biomarkers that may have potential clinical utility to identify ACS patients. Patho-physiology, analytical and clinical characteristics have been evaluated for each marker, underlying the properties for potential routine clinical use. SUMMARY: The biomarkers discussed in this review are promising and might lead to improved diagnosis and risk stratification of patients with ACS, however their clinical application requires further studies. It is important to define their clinical role as diagnostic markers, their predictive value and the specificity, standardization and detection limits of the assays.

Diagnostic value of ischaemia-modified albumin for predicting myocardial ischaemia during myocardial perfusion scintigraphy

During acute ischaemia the N-terminal site of albumin is altered, reducing its binding capacity; the modified protein is termed ischaemia-modified albumin (IMA). IMA is a sensitive marker of acute myocardial ischaemia but its diagnostic value in chronic angina pectoris patients is unclear. We investigated changes in blood levels of IMA during myocardial perfusion scintigraphy in patients with chronic angina pectoris in a study including 26 male and 20 female patients, with mean age 60 years. Technetium 99m perfusion imaging detected myocardial ischaemia in 26 patients. Coronary angiography was carried out in these 26 ischaemic patients. Mean IMA values at rest and peak exercise were significantly higher in the ischaemic than the nonischaemic group. All IMA values were considered negative for cardiac ischaemia. Peak exercise IMA was significantly lower than the pre-exercise level only in the non-ischaemic group. IMA measurements during myocardial perfusion scintigraphy are not helpful in the diagnosis of myocardial ischaemia in patients with stable angina pectoris.

Biomarkers in Cardiovascular Disease: Integrating Pathophysiology into Clinical Practice

Biomarkers play an important role in the diagnosis, prognostic assessment, and management of patients with suspected acute coronary syndromes (ACS). Specific biomarkers identify different components of the pathophysiology of ACS: troponins are prototype markers of myocyte necrosis, natriuretic peptides reflect neurohormonal activation and hemodynamic stress, soluble CD40 ligand is an indicator of platelet activation, and C-reactive protein, myeloperoxidase, and monocyte chemoattractant protein-1 reflect various inflammatory processes. When combined, multiple biomarkers reflecting different pathophysiologic processes appear to enhance risk stratification, as compared with using individual markers alone. Advances in proteomic technology promise to identify additional novel biomarkers that facilitate diagnosis, risk stratification, and selection of therapies in ACS. In the future, it is hoped that multiple biomarker panels will form the basis of an individualized approach to the treatment of ACS, in which therapy is tailored to individual biomarker profiles.

Influence of physical exercise and relationship with biochemical variables of NT-pro-brain natriuretic peptide and ischemia modified albumin

BACKGROUND

The diagnostic approach and the clinical management of patients presenting with suspected acute coronary syndrome or cardiac dysfunction are as yet challenging. Although ischemia modified albumin (IMA) and natriuretic peptides were recently proposed for detection of myocardial ischemia and cardiac dysfunction, little information is available on preanalytical and metabolic sources of variability of these markers.

METHODS

To establish the influence of a regular endurance training and the relationship with conventional biochemical variables, NT-pro-brain natriuretic peptide (NT-proBNP) and IMA were assayed, along with cardiac troponin T (cTnT), lactate dehydrogenase (LDH), creatine kinase (CK), creatinine and albumin, in 35 sedentary healthy individuals and 50 male professional road cyclists, 12-24 h following the last demanding training session.

RESULTS

Athletes displayed higher values of both LDH (299+/-61 vs. 257+/-36 U/l, P=0.002) and CK (184+/-123 vs. 115+/-74 U/l, P=0.011), and slightly lower concentrations of creatinine (82+/-12 vs. 87+/-9 micromol/l, P=0.044). No athlete or sedentary control displayed cTnT concentrations exceeding the lower sensitivity limit of the assay. As compared to the sedentary controls, main IMA concentration was increased in athletes (100+/-13 vs. 94+/-6 KU/l, P=0.035), whereas that of NT-proBNP appeared significantly decreased (2.8+/-1.6 vs. 4.3+/-34, P=0.005). The percentage of subjects displaying values exceeding the upper reference limit for the IMA assay was significantly different between athletes and sedentary controls (50% vs. 7%; P<0.001). Pearson correlation analysis revealed an inverse association between IMA and albumin in both athletes (r=-0.640; P<0.001) and sedentary controls (r=-0.583; P=0.001).

CONCLUSIONS

Results of our investigation indicate that a demanding and regular aerobic training regimen, though able to trigger skeletal muscle sufferance, is not associated with any biochemical sign of severe and irreversible chronic cardiac involvement. Moreover, we suggest the adoption of specific IMA diagnostic thresholds following patients' stratification according to serum albumin concentration and physical activity.

La troponine et les autres marqueurs de souffrance myocardique, quelle signification en médecine interne ?

PURPOSE

Troponin is now the gold standard for the diagnosis of myocardial infarction. Aiming at improving the management of a patient suspect of an acute coronary syndrome, this article will point the interpretation of troponin dosages according to the clinical presentation and concomitant diseases.

ACTUALITIES

First, the interest of troponin dosage as compared with other markers of myocardial ischemia will be underlined. Then, the literature available about troponin in cardiovascular diseases but also in extracardiac diseases will be analysed. Finally, the difficulties of assay will be discussed.

PERSPECTIVES

The availability of a sensitive and specific marker such as troponin is definitively a progress in the management of patients with an acute coronary syndromes. But it remains a biological contribution to the global management of the patient. It is important to know the causes susceptible to increase the levels of troponin to avoid a wrong interpretation of the dosage, leading to diagnostic but also therapeutic mistakes.