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Xiong H, Zhu C, Dai C, Ye X, Li Y, Li P, Yang S, Ashraf G, Wei D, Chen H, Shen H, Kong J, Fang X. An Alternating Current Electroosmotic Flow-Based Ultrasensitive Electrochemiluminescence Microfluidic System for Ultrafast Monitoring, Detection of Proteins/miRNAs in Unprocessed Samples. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307840. [PMID: 38070186 PMCID: PMC10853704 DOI: 10.1002/advs.202307840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/16/2023] [Indexed: 02/10/2024]
Abstract
Early diagnosis of acute diseases is restricted by the sensitivity and complex process of sample treatment. Here, an ultrasensitive, rapid, and portable electrochemiluminescence-microfluidic (ECL-M) system is described via sandwich-type immunoassay and surface plasmonic resonance (SPR) assay. Using a sandwich immunoreaction approach, the ECL-M system employs cardiac troponin-I antigen (cTnI) as a detection model with a Ru@SiO2 NPs labeled antibody as the signal probe. For miR-499-5p detection, gold nanoparticles generate SPR effects to enhance Ru(bpy)3 2+ ECL signals. The system based on alternating current (AC) electroosmotic flow achieves an LOD of 2 fg mL-1 for cTnI in 5 min and 10 aM for miRNAs in 10 min at room temperature. The point-of-care testing (POCT) device demonstrated 100% sensitivity and 98% specificity for cTnI detection in 123 clinical serum samples. For miR-499-5p, it exhibited 100% sensitivity and 97% specificity in 55 clinical serum samples. Continuous monitoring of these biomarkers in rats' saliva, urine, and interstitial fluid samples for 48 hours revealed observations rarely documented in biotic fluids. The ECL-M POCT device stands as a top-performing system for ECL analysis, offering immense potential for ultrasensitive, rapid, highly accurate, and facile detection and monitoring of acute diseases in POC settings.
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Affiliation(s)
- Huiwen Xiong
- Department of ChemistryFudan UniversityShanghai200438P. R. China
| | - Chenxin Zhu
- Institutes of Biomedical Sciences and Minhang HospitalFudan UniversityShanghai200032P. R. China
| | - Changhao Dai
- State Key Laboratory of Molecular Engineering of PolymersDepartment of Macromolecular ScienceFudan UniversityShanghai200438P. R. China
| | - Xin Ye
- Department of Laboratory MedicineThe First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShaanxi710061P. R. China
| | - Yuanyuan Li
- Yizheng Hospital of Traditional Chinese MedicineYangzhou211400P. R. China
| | - Pintao Li
- Department of ChemistryFudan UniversityShanghai200438P. R. China
| | - Shuang Yang
- Institutes of Biomedical Sciences and Minhang HospitalFudan UniversityShanghai200032P. R. China
| | - Ghazala Ashraf
- Department of ChemistryFudan UniversityShanghai200438P. R. China
| | - Dacheng Wei
- State Key Laboratory of Molecular Engineering of PolymersDepartment of Macromolecular ScienceFudan UniversityShanghai200438P. R. China
| | - Hui Chen
- Department of ChemistryFudan UniversityShanghai200438P. R. China
| | - Huali Shen
- Institutes of Biomedical Sciences and Minhang HospitalFudan UniversityShanghai200032P. R. China
| | - Jilie Kong
- Department of ChemistryFudan UniversityShanghai200438P. R. China
| | - Xueen Fang
- Department of ChemistryFudan UniversityShanghai200438P. R. China
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Wang L, Zhang W, Song B, Zhang Z, Li J, Li X, Yao J. Development of a system for detecting cardiac troponin I by background fluorescence quenching based on internal filtration effect. NANOTECHNOLOGY 2023; 35:115705. [PMID: 38035391 DOI: 10.1088/1361-6528/ad1163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Accepted: 11/30/2023] [Indexed: 12/02/2023]
Abstract
The present study sought to develop a cardiac troponin I (cTnI) detection system based on background fluorescence quenching of internal filtration effect (IFE) and study the influence of IFE on the sensitivity of cTnI detection. Three nanogold materials were synthesized as fluorescence quenchers, and rhodamine 6 G (R6G) and Cy5 were used as fluorescence probes. Six experimental systems were established to detect cTnI in negative serum test solutions and clinical serum samples. The sensitivity of each system was compared to explore the contribution of IFE to the detection sensitivity of cTnI. When applied to negative serum test solutions, the R6G-nanogold material I system exhibited a superior detection effect for cTnI, with a limit of detection (LOD) of 0.15 ng ml-1. When applied to clinical serum samples, the Cy5-nanogold material Ⅲ system yielded a better detection effect for cTnI, with the lowest concentration of cTnI detected at 2 ng ml-1. The first and second internal filtering effects in the proposed system can be achieved simultaneously, effectively avoiding light absorption interference from clinical serum samples and enhancing the sensitivity of the background fluorescence quenching detection of cTnI.
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Affiliation(s)
- Lei Wang
- College of Pharmacy, Xinjiang Medical University, Urumqi, Xinjiang 830017, People's Republic of China
- Key Laboratory of Active Components of Xinjiang Natural Medicine and Drug Release Technology, Urumqi, Xinjiang 830017, People's Republic of China
| | - Wei Zhang
- The Second Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830063, People's Republic of China
| | - Bailing Song
- Xinjiang Hu Suan Research Institute (Co., LTD), Urumqi, 830020, People's Republic of China
| | - Ziyi Zhang
- College of Pharmacy, Xinjiang Medical University, Urumqi, Xinjiang 830017, People's Republic of China
- Key Laboratory of Active Components of Xinjiang Natural Medicine and Drug Release Technology, Urumqi, Xinjiang 830017, People's Republic of China
| | - Jiutong Li
- College of Pharmacy, Xinjiang Medical University, Urumqi, Xinjiang 830017, People's Republic of China
- Shanghai Simp Bio-Science Co., Ltd, Shanghai 201800, People's Republic of China
| | - Xinxia Li
- College of Pharmacy, Xinjiang Medical University, Urumqi, Xinjiang 830017, People's Republic of China
- Key Laboratory of Active Components of Xinjiang Natural Medicine and Drug Release Technology, Urumqi, Xinjiang 830017, People's Republic of China
- Xinjiang Hu Suan Research Institute (Co., LTD), Urumqi, 830020, People's Republic of China
| | - Jun Yao
- College of Pharmacy, Xinjiang Medical University, Urumqi, Xinjiang 830017, People's Republic of China
- Key Laboratory of Active Components of Xinjiang Natural Medicine and Drug Release Technology, Urumqi, Xinjiang 830017, People's Republic of China
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Niu P, Jiang J, Liu K, Wang S, Jing J, Xu T, Wang T, Liu Y, Liu T. Fiber-integrated WGM optofluidic chip enhanced by microwave photonic analyzer for cardiac biomarker detection with ultra-high resolution. Biosens Bioelectron 2022; 208:114238. [PMID: 35390720 DOI: 10.1016/j.bios.2022.114238] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 02/28/2022] [Accepted: 03/29/2022] [Indexed: 12/30/2022]
Abstract
Cardiac troponin I (cTnI) plays an important role in emergency diagnosis of cardiovascular diseases, which exists predominately in the form of cardiac troponin I-C (cTnI-C) complex. We proposed a fiber-integrated optofluidic chip immunosensor with time-delay-dispersion based microwave photonic analyzer (MPA) for cTnI-C detection. The whispering gallery mode (WGM) fiber probe was fabricated by embedding a polydopamine functionalized hollow glass microsphere (HGMS) into the etched capillary-fiber structure, and the WGMs could be excited through the efficient coupling between the thin-wall capillary and the HGMS. The reflective WGM optofluidic chip functioned as a wavelength tuner to construct fiber ring laser cavity, whose laser output wavelength was cTnI-C concentration-dependent. The tiny wavelength variation of sensing laser was converted into a radio-frequency (RF) response, which was retrieved by measuring the change of RF-domain free spectrum range (FSR) in time-delay-dispersion based MPA, and the quantitative detection of cTnI-C complex can be achieved with high resolution. Experimental results show that this immunosensor had a limit of detection (LOD) of 0.59 ng/mL, and a detection resolution of 1.2 fg/mL. The relative resolving power was 102-104-fold higher than that of others optical fiber cTnI biosensors. The proposed fiber-integrated optofluidic chip provides an innovative lab-on-chip diagnostic tool for myocardial damage.
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Affiliation(s)
- Panpan Niu
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Junfeng Jiang
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China.
| | - Kun Liu
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Shuang Wang
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Jianying Jing
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Tianhua Xu
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Tong Wang
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Yize Liu
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
| | - Tiegen Liu
- School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China
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Adamcová M, Kokštein Z, Vávrová J. Clinical Utility of Cardiac Troponin I and Cardiac Troponin T Measurements. ACTA MEDICA (HRADEC KRÁLOVÉ) 2020. [DOI: 10.14712/18059694.2020.50] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The measurement of CK-MB remains the test of choice for confirmation or exclusion of AMI and probably will remain the test of choice for routine diagnosis in the near future. Nowadays determination of cardiac troponin T (cTnT) and cardiac troponin I (cTnI) as a method relatively expensive and time-consuming should be restricted to clinical settings that really require their high specificity.
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Zhu L, Ye J, Yan M, Zhu Q, Wang S, Huang J, Yang X. Electrochemiluminescence Immunosensor Based on Au Nanocluster and Hybridization Chain Reaction Signal Amplification for Ultrasensitive Detection of Cardiac Troponin I. ACS Sens 2019; 4:2778-2785. [PMID: 31571481 DOI: 10.1021/acssensors.9b01369] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Measurement of cardiac troponin I in the blood is crucial for the early diagnosis of acute myocardial infarction. Herein, a novel and ultrasensitive electrochemiluminescence (ECL) immunosensor has been developed for determination of cardiac troponin I (cTnI) by using Au nanoclusters and hybridization chain reaction (HCR) signal amplification. In this ECL immunosensor, Au nanoclusters were dual-labeled at each end of hairpin DNA (H1 and H2) and acted as the luminophore. DNA initiator strands (T1) and secondary antibody (Ab2) were conjugated on Au nanoparticles (AuNPs) to obtain a smart probe (Ab2-AuNP-T1). In the presence of target cTnI, the sandwiched immunocomplex composed of cTnI, Ab1, and Ab2-AuNP-T1 was formed. Then the initiator strands T1 of Ab2-AuNP-T1 opened the hairpin DNA structures and triggered a cascade of hybridization events. Consequently, a large number of Au NCs were indirectly modified on the surface of the electrode, which could react with the coreactant (K2S2O8) and emit a strong ECL signal. Under the optimal conditions, the immunosensor exhibited a wide detection range for cTnI from 5 fg/mL to 50 ng/mL and a low detection limit of 1.01 fg/mL (S/N = 3). Because of the excellent specificity, stability, and reproducibility of the proposed ECL-HCR sensor, it has a great application prospect for cTnI detection in clinical diagnosis.
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Affiliation(s)
- Liping Zhu
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Jing Ye
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Mengxia Yan
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Qiuju Zhu
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Shuang Wang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Jianshe Huang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Xiurong Yang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
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6
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El-Kased RF. Immuno-analytical approach and its application for cardiac disease marker detection. J Immunoassay Immunochem 2018; 39:538-550. [PMID: 30212265 DOI: 10.1080/15321819.2018.1518241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Cardiac troponin-I is a promising diagnostic marker for cardiovascular diseases. Troponin-I immunoassays rely on monoclonal antibodies, while polyclonal antibodies, cheaper to manufacture, are uncommonly used. The current study established an immuno-analytical assay using a polyclonal antibody capable of mapping troponin-I antigenic determinant. Proteolytic digestion of troponin-I was performed. Antigenic determinant was assigned by separation of fragments using gel electrophoresis followed by Western blot and high-performance liquid chromatography followed by dot blot. The antigenic determinant region appeared within amino acid sequence 30-90. This robust procedure is suitable for early prognosis of diseases, stratification of patients, and possibly individualized therapy.
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Affiliation(s)
- Reham F El-Kased
- a Microbiology and Immunology, Faculty of Pharmacy , The British University in Egypt (BUE) , Cairo , Egypt
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Bose A, Jain V, Kawthekar G, Chhabra C, Hemvani N, Chitnis DS. The Importance of Serial Time Point Quantitative Assessment of Cardiac Troponin I in the Diagnosis of Acute Myocardial Damage. Indian J Crit Care Med 2018; 22:629-631. [PMID: 30294127 PMCID: PMC6161573 DOI: 10.4103/ijccm.ijccm_8_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE The present study was aimed to establish a threshold value for cardiac troponin I (cTnI) for nonacute coronary syndrome (ACS) participants from the local population and also to determine the importance of serial time point estimation of cTnI in acute myocardial infarction (AMI), non-ST-elevated MI (NSTEMI), and unstable angina cases. METHODS The present study included 194 cases, admitted in ICCU with the complaint of anginal pain; 31 were diagnosed with AMI with typical electrocardiography (ECG) changes; whereas, 48 cases were diagnosed with NSTEMI. The latter group of cases was selected for the time point study of cTnI release at 0-4 h, 6-12 h, 72 h, and 144 h of admission. cTnI levels were assessed using the Abbott ARCHITECT i1000SR system. RESULTS ACS was clinically ruled out in 98 cases, and cTnI level for them was used to decide cTnI threshold for the non-ACS group. cTnI level was checked in 17 cases of unstable angina. The threshold value of cTnI for non-ACS participants was 0.1 ng/ml and can be considered as cut-off value for the regional population. The data suggested that the peak of cTnI levels in most of the AMI cases reached during 6-12 h. The cTnI levels were lower than 0.1 ng/ml, and no significant change in ECG was noticed in 17 cases of unstable angina. CONCLUSION The present study suggested that the repeat of cTnI assay after 4-6 h of admission is required if the initial value is <3 ng/ml.
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Affiliation(s)
- Arindam Bose
- Department of Pathology, Choithram Hospital and Research Centre, Indore, Madhya Pradesh, India
| | - Vidyut Jain
- Department of Cardiology, Choithram Hospital and Research Centre, Indore, Madhya Pradesh, India
| | - Girish Kawthekar
- Department of Cardiology, Choithram Hospital and Research Centre, Indore, Madhya Pradesh, India
| | - Chandrabala Chhabra
- Department of Cardiology, Choithram Hospital and Research Centre, Indore, Madhya Pradesh, India
| | - Nanda Hemvani
- Department of Pathology, Choithram Hospital and Research Centre, Indore, Madhya Pradesh, India
| | - Dhananjay S. Chitnis
- Department of Pathology, Choithram Hospital and Research Centre, Indore, Madhya Pradesh, India
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Wu Q, Sun Y, Zhang D, Li S, Zhang Y, Ma P, Yu Y, Wang X, Song D. Ultrasensitive magnetic field-assisted surface plasmon resonance immunoassay for human cardiac troponin I. Biosens Bioelectron 2017; 96:288-293. [PMID: 28505563 DOI: 10.1016/j.bios.2017.05.023] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 05/09/2017] [Accepted: 05/11/2017] [Indexed: 10/19/2022]
Abstract
An ultrasensitive surface plasmon resonance (SPR) immunoassay was developed for the specific detection of human cardiac troponin I (cTnI), a principle diagnostic marker for myocardial damage. The thin gold film evaporated on a glass slate, which was employed as the SPR sensing film, was modified by hollow gold nanoparticles (HGNPs) and polydopamine (PDA) sequentially, and then was immobilized with antibodies for specific recognition of target analyte. Electronic coupling of the surface plasmon waves originating from the HGNPs and the gold film leads to the remarkable amplification of SPR response. The PDA film modified on the gold film via self-polymerization of dopamine (DA) facilitates the direct immobilization of capture antibodies (cAb). To separate and enrich the target analyte, PDA-wrapped magnetic multi-walled carbon nanotubes (MMWCNTs-PDA) were conjugated with detection antibodies (dAb) and used as the extracting agent for the magnetic extraction of cTnI in sample. Large surface area of MMWCNTs-PDA ensures its loading capacity for dAb, as well as its extraction efficiency for cTnI. By serving as the "vehicles" for fast delivering the concentrated analyte to the SPR sensing surface, MMWCNTs-PDA-dAb also overcomes the disadvantage of slow diffusion-limited mass transfer and matrix interference effect in regular patterns. The combination of the above improvements results in the significant sensitivity enhancement of the SPR immunoassay. The concentration of cTnI with minimum detectable SPR response obtained by the present assay is 1.25ngmL-1, which is 1000-fold lower than that obtained by the traditional SPR immunoassay based on PDA-modified gold film.
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Affiliation(s)
- Qiong Wu
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Ying Sun
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Di Zhang
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Shuo Li
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Yue Zhang
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Pinyi Ma
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Yang Yu
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Xinghua Wang
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China
| | - Daqian Song
- College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, PR China.
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Sharma A, Han CH, Jang J. Rapid electrical immunoassay of the cardiac biomarker troponin I through dielectrophoretic concentration using imbedded electrodes. Biosens Bioelectron 2016; 82:78-84. [DOI: 10.1016/j.bios.2016.03.056] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 03/08/2016] [Accepted: 03/22/2016] [Indexed: 12/31/2022]
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Iribarren C, Chandra M, Rana JS, Hlatky MA, Fortmann SP, Quertermous T, Go AS. High-sensitivity cardiac troponin I and incident coronary heart disease among asymptomatic older adults. Heart 2016; 102:1177-82. [PMID: 27030599 DOI: 10.1136/heartjnl-2015-309136] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 02/25/2016] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE High-sensitivity cardiac troponin I (hs-cTnI) is a novel biomarker of myocardial injury and ischaemia. Our objective was to ascertain correlates of hs-cTnI and its incremental prognostic utility for incident coronary heart disease (CHD) among older asymptomatic subjects. METHODS We performed a cohort study among 1135 asymptomatic control participants in the ADVANCE (Atherosclerotic Disease, VAscular FunctioN and GenetiC Epidemiology) study at Kaiser Permanente Northern California and Stanford University, with follow-up through 31 December 2014. Hs-cTnI was measured in stored baseline (2002-2004) serum samples. RESULTS After a median follow-up of 11.3 years, 164 CHD events were documented. The most significant correlates of hs-cTnI were black race, body mass index, hypertension, LDL cholesterol and estimated glomerular filtration rate (eGFR) (R(2)=0.16) After adjustment for race/ethnicity, education level, diabetes status, ATP-III Framingham risk score (FRS), C reactive protein and eGFR, each 1 SD increment of log-transformed Hs-cTnI was associated with 1.11 (95% CI 1.01 to 1.23, p=0.04) increased hazard of CHD. The c-statistic increased to 0.70 from 0.68 (p=0.16) and the category-based net reclassification index was 18% (95% CI 8% to 30%) after adding hs-cTnI to the model containing the ATP-III FRS. CONCLUSIONS Hs-cTnI conveys incremental prognostic information for incident CHD among asymptomatic older adults.
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Affiliation(s)
- Carlos Iribarren
- Kaiser Permanente Northern California Division of Research, Oakland, California, USA San Francisco Departments of Epidemiology, University of California, Biostatistics and Medicine, San Francisco, California, USA
| | - Malini Chandra
- Kaiser Permanente Northern California Division of Research, Oakland, California, USA
| | - Jamal S Rana
- Division of Cardiology, Kaiser Permanente Oakland Medical Center, Oakland, California, USA
| | - Mark A Hlatky
- Stanford University School of Medicine, Palo Alto, California, USA
| | - Stephen P Fortmann
- Stanford University School of Medicine, Palo Alto, California, USA Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon, USA
| | | | - Alan S Go
- Kaiser Permanente Northern California Division of Research, Oakland, California, USA San Francisco Departments of Epidemiology, University of California, Biostatistics and Medicine, San Francisco, California, USA Stanford University School of Medicine, Palo Alto, California, USA
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Tuteja SK, Kukkar M, Suri C, Paul A, Deep A. One step in-situ synthesis of amine functionalized graphene for immunosensing of cardiac marker cTnI. Biosens Bioelectron 2015; 66:129-35. [DOI: 10.1016/j.bios.2014.10.072] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 10/21/2014] [Accepted: 10/27/2014] [Indexed: 11/15/2022]
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12
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Li Y, Wang X, Xu L, Wen X. Rapid Identification of Falsely Elevated Serum Cardiac Troponin I Values in a Stat Laboratory. Lab Med 2014; 45:82-5. [DOI: 10.1309/lmo7hli8eodnazsg] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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13
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Aldous SJ. Cardiac biomarkers in acute myocardial infarction. Int J Cardiol 2012; 164:282-94. [PMID: 22341694 DOI: 10.1016/j.ijcard.2012.01.081] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 12/16/2011] [Accepted: 01/26/2012] [Indexed: 01/11/2023]
Abstract
Each year, a large number of patients are seen in the Emergency Department with presentations necessitating investigation for possible acute myocardial infarction. Patients can be stratified by symptoms, risk factors and electrocardiogram results but cardiac biomarkers also have a prime role both diagnostically and prognostically. This review summarizes both the history of cardiac biomarkers as well as currently available (established and novel) assays. Cardiac troponin, our current "gold standard" biomarker criterion for the diagnosis of myocardial infarction has high sensitivity and specificity for this diagnosis and therapies instituted in patients with elevated troponin have been shown to influence outcomes. Other markers of myocardial necrosis, inflammation and neurohormonal activity have also been shown to have either diagnostic or prognostic utility, but none have been shown to be superior to troponin. The measurement of multiple biomarkers and the use of point of care markers may accelerate current diagnostic protocols for the assessment of such patients.
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Shen W, Tian D, Cui H, Yang D, Bian Z. Nanoparticle-based electrochemiluminescence immunosensor with enhanced sensitivity for cardiac troponin I using N-(aminobutyl)-N-(ethylisoluminol)-functionalized gold nanoparticles as labels. Biosens Bioelectron 2011; 27:18-24. [DOI: 10.1016/j.bios.2011.05.022] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 05/09/2011] [Accepted: 05/12/2011] [Indexed: 11/29/2022]
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LeLeiko RM, Vaccari CS, Sola S, Merchant N, Nagamia SH, Thoenes M, Khan BV. Usefulness of elevations in serum choline and free F2)-isoprostane to predict 30-day cardiovascular outcomes in patients with acute coronary syndrome. Am J Cardiol 2009; 104:638-43. [PMID: 19699337 DOI: 10.1016/j.amjcard.2009.04.047] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Revised: 04/26/2009] [Accepted: 04/26/2009] [Indexed: 11/19/2022]
Abstract
Our objectives were to evaluate the prognostic value of several biomarkers in patients with acute coronary syndrome (ACS) through an evaluation of the 30-day clinical outcomes. Multiple biomarkers have emerged as potentially useful in risk stratification of ACS. Specifically, markers of vascular inflammation and oxidative stress might be helpful in the determination of clinical outcomes. We evaluated patients presenting with chest pain. ACS was defined by symptoms of cardiac ischemia plus electrocardiographic changes or positive troponin I. Levels of serum troponin I, high sensitivity C-reactive protein, serum choline, and free F(2)-isoprostane were obtained. Patients were followed up for 30 days (n = 108) with determination of nonfatal myocardial infarction, congestive heart failure, need for revascularization, and death. Of the 108 patients, 26 had a cardiac event. Free F(2)-isoprostane and choline levels (but not high-sensitivity C-reactive protein levels) predicted 30-day cardiac events. To determine the value of choline and F(2)-isoprostane levels in predicting 30-day cardiac events, receiver operating curves were generated. The optimal cutoff point of these markers was a serum F(2)-isoprostane level of 124.5 pg/ml (r = 0.82) and a serum choline level of 30.5 mumol/L (r = 0.76). F(2)-isoprostane and choline had a positive predictive value of 57% and 44% and a negative predictive value of 90% and 89%, respectively. In conclusion, serum choline and free F(2)-isoprostane are predictors of cardiac events in ACS. A model that includes an array of biomarkers, including troponin, choline, and free F(2)-isoprostane, might be useful in predicting patients at greater risk of future events in ACS.
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Affiliation(s)
- Rebecca M LeLeiko
- Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
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Abstract
Coronary artery bypass graft (CABG) surgery, performed for the control of angina pectoris, leads to postoperative relief from symptoms in most patients. Amelioration of ischemia and improvement in exercise capacity after CABG are well documented. However, patients currently undergoing CABG are more complex than in the past--they are older and are maintained on medical therapy for longer periods. A large number of these patients have had one or more previous myocardial revascularization procedures. The post-operative period would appear to be a time of vulnerability for coronary events. However, previous investigators have focused on the pre- and intraoperative aspects of peri-CABG ischemia. Outcome data suggest that the postoperative interval is at least equally important as a determinant of short- and long-term morbidity and mortality. We discuss the epidemiology, etiology, pathophysiology, and treatment of ischemic syndromes in the postoperative period after CABG. In addition, we review recent data from a series of 14 patients, observed at our institution, who underwent cardiac catheterization and, in some cases, angioplasty of the culprit vessel in the immediate postoperative period.
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Affiliation(s)
- W S Hirsch
- Division of Cardiovascular Disease, Albert Einstein Medical Center, Philadelphia, Pennsylvania 19141, USA
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Iser DM, Thompson AJV, Sia KK, Yeomans ND, Chen RYM. Prospective study of cardiac troponin I release in patients with upper gastrointestinal bleeding. J Gastroenterol Hepatol 2008; 23:938-42. [PMID: 17559373 DOI: 10.1111/j.1440-1746.2007.04940.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND AIM The rate of cardiac injury in upper gastrointestinal hemorrhage is unclear. The aims of this study were to determine prospectively the risk of cardiac troponin I release and associated adverse cardiac events in patients with acute upper gastrointestinal hemorrhage. METHODS From January to September 2003, we prospectively studied patients with documented hematemesis and melena referred to the gastroenterology unit in a tertiary teaching hospital in Melbourne, Australia. Serial assays for cardiac troponin I were performed at 0, 12 and 24 h. Serial creatine kinase levels and electrocardiographs were also performed. Clinical and biochemical data were collected. The primary endpoint was a troponin level >0.5 microg/L within 24 h of recruitment. Various clinical variables were then compared between the groups of patients with or without troponin rise. RESULTS A total of 156 patients were included in the study. The mean age was 67 years (range 19-96). There were 104 (67%) male patients. A troponin level of greater than 0.5 microg/L was found in 30/156 (19%); 126 (81%) patients had normal troponin levels. Age greater than 65 years, signs of hemodynamic instability at presentation, a recent history of cardiac disease, cardiovascular compromise following endoscopy, and re-bleeding were associated with troponin release. CONCLUSION Upper gastrointestinal bleeding is associated with a risk of cardiac injury of up to 19%. Troponin assay could be used to screen for cardiac damage, especially in elderly patients who present with hemodynamic instability.
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Affiliation(s)
- David M Iser
- Department of Medicine, The University of Melbourne, Western Hospital, Melbourne, Victoria, Australia.
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Ko S, Kim B, Jo SS, Oh SY, Park JK. Electrochemical detection of cardiac troponin I using a microchip with the surface-functionalized poly(dimethylsiloxane) channel. Biosens Bioelectron 2007; 23:51-9. [PMID: 17462876 DOI: 10.1016/j.bios.2007.03.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Revised: 01/26/2007] [Accepted: 03/19/2007] [Indexed: 10/23/2022]
Abstract
A sensitive and rapid electrochemical microchip fabricated by assembling a surface-functionalized poly(dimethylsiloxane) (PDMS) microchannel with an interdigitated array (IDA) gold electrode was developed for the detection of human cardiac troponin I (cTnI) in the early diagnosis of acute myocardial infarction. Anti-cTnI was immobilized onto the internal surface of the PDMS channel on which protein G layer had been generated by silanization. To reduce electrode fouling, a PDMS channel was assembled with an IDA chip after surface treatment. The detection experiments were performed with successive injection of cTnI, alkaline phosphatase (AP)-labeled anti-cTnI, and p-aminophenylphosphate. Then, cyclic voltammograms were obtained by the oxidation peak current proportionally to the concentration of enzymatic product, p-aminophenol. The optimal packing density of anti-cTnI on the surface of the PDMS channel was determined at the anti-cTnI concentration of 30 microg/ml for the highest electrochemical signal. These demonstrate that the proper orientation and best packing density of antibody as well as no electrode fouling contributed to the low detection limit (148 pg/ml) of cTnI within 8 min.
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Affiliation(s)
- Sungho Ko
- Food Nanotechnology Research Group, Korea Food Research Institute, San 46-1, Baekyun-dong, Bundang-gu, Seongnam, Gyeonggi-do 463-746, Republic of Korea
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Johansson AM, Gardner SY, Atkins CE, LaFevers DH, Breuhaus BA. Cardiovascular Effects of Acute Pulmonary Obstruction in Horses with Recurrent Airway Obstruction. J Vet Intern Med 2007. [DOI: 10.1111/j.1939-1676.2007.tb02964.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Adamcova M, Sterba M, Simunek T, Potacova A, Popelova O, Mazurova Y, Gersl V. Troponin as a marker of myocardiac damage in drug-induced cardiotoxicity. Expert Opin Drug Saf 2006; 4:457-72. [PMID: 15934853 DOI: 10.1517/14740338.4.3.457] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Cardiac troponins T and I (cTnT and cTnI) are becoming the serum biomarkers of choice for monitoring potential drug-induced myocardial injury in both clinical and preclinical studies. The utility of cardiac troponins has been mainly demonstrated following the administration of antineoplastic drugs and beta-sympathomimetics, although the routine use of these markers in the monitoring in patients who received anthracyclines therapy is far from settled. Unlike the previous markers, which suffered from numerous shortages, the main advantages of cardiac troponins are their high specificity and sensitivity, wide diagnostic window and the possibility to use commercially available assays in clinical settings as well as in a broad range of laboratory animals. Nevertheless, in spite of vigorous research in this area, a number of questions are still unanswered and these are discussed in this review. The main problems seem to be the lack of standardisation of variety of troponin immunoassays, the assessment of suitable cutoff for drug-induced cardiotoxicity and determination of critical diagnostic window related to the optimal timing of sample collection, which may be drug-dependent.
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Affiliation(s)
- Michaela Adamcova
- Department of Physiology, Charles University in Prague, Faculty of Medicine, Simkova 870, 500 38, Hradec Králové, Czech Republic.
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Rajan GP, Zellweger R. Cardiac Troponin I as a Predictor of Arrhythmia and Ventricular Dysfunction in Trauma Patients With Myocardial Contusion. ACTA ACUST UNITED AC 2004; 57:801-8; discussion 808. [PMID: 15514534 DOI: 10.1097/01.ta.0000135157.93649.72] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Myocardial contusion during blunt chest trauma is common and may lead to potentially fatal cardiac complications. Therefore, it is useful to identify a serum marker reflecting the myocardial damage that can predict risk for cardiac complications. In this study, the authors determined the strength of the association between cardiac troponin I (cTnI) levels and the risk of arrhythmia or the development of left ventricular dysfunction in a cohort of patients with blunt chest trauma. METHODS AND RESULTS In 187 multiply injured patients with blunt chest trauma, serial measurements of cTnI, total creatine kinase (CK), and isoenzyme of creatine kinase with muscle and brain subunits (CK-MB) were combined with sequential electrocardigraphic and echocardiographic recordings. The results showed that 63 patients (34%) had myocardial contusion, as defined by positive cTnI levels, of which 47 (25%) were symptomatic and 16 (9%) showed no abnormalities. The remaining 124 patients (66%) displaying negative CTnI levels were asymptomatic during the entire study. Severity of arrhythmia correlated directly with increase in cTnI levels. The levels of cTnI in the symptomatic group remained elevated significantly longer than the levels in the asymptomatic group. The depression of left ventricular ejection fraction was inversely correlated with the increase in cTn levels. The patients whose cTnI levels were below 1.05 microg/L at admission and during the first 6 hours afterward showed no cardiac abnormalities throughout the entire study period CONCLUSIONS Levels of cTnI below 1.05 microg/L in asymptomatic patients at admission and within the first 6 hours after admission rule out myocardial injury, whereas positive cTn levels above 1.05 microg/L mandate further cardiologic workup for the detection and management of myocardial injury. Furthermore, the dynamics and peak levels of pathologic cTnI levels allow estimation of arrhythmia risk and left ventricular dysfunction in trauma patients with myocardial contusion.
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Affiliation(s)
- Gunesh P Rajan
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Zurich, Zurich, Switzerland.
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Wei J, Mu Y, Song D, Fang X, Liu X, Bu L, Zhang H, Zhang G, Ding J, Wang W, Jin Q, Luo G. A novel sandwich immunosensing method for measuring cardiac troponin I in sera. Anal Biochem 2004; 321:209-16. [PMID: 14511686 DOI: 10.1016/s0003-2697(03)00407-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Common methods for monitoring human cardiac troponin I (cTn I) are based on using antibodies against cTn I labeled with horseradish peroxidase, radioactive isotopes, or other labels. In this study, a novel label-free sandwich immunosensing method for measuring cTn I was developed. Three monoclonal antibodies (mAbs 9F5, 2F11, and 8C12) against human cTn I were generated by the commonly used hybridoma technique and characterized by a surface plasmon resonance (SPR) biosensor. An optimal pair of mAbs for measuring human cTn I was selected, as both mAbs have high affinities for cTn I and do not compete against each other for cTn I binding. An optical immunosensor for measuring cTn I in sera based on SPR was developed by using avidin as an intermediate layer and biotinylated-2F11 as the capturing antibody. Two detection methods for cTn I with the immunosensor were performed: (1) the direct detection of cTn I with a detection range of 2.5 to 40 microg/L and (2) the sandwich immunosensing method. In the sandwich assay mode, the second antibody 9F5 biologically amplified the sensor response. As a result, the sandwich assay showed a sensitivity of 0.25 microg/L and a detection range of 0.5 to 20 microg/L with within-run variation of 4.9 to 6.7% and between-run variation of 5.2 to 8.4%. This method has greatly enhanced the sensitivity for detection compared to that previously reported in the literatures.
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Affiliation(s)
- Jingyan Wei
- Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education, and College of Pharmacy, Jilin University, Changchun 130023, China
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Checchia PA, Sehra R, Moynihan J, Daher N, Tang W, Weil MH. Myocardial injury in children following resuscitation after cardiac arrest. Resuscitation 2003; 57:131-7. [PMID: 12745180 DOI: 10.1016/s0300-9572(03)00003-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Myocardial dysfunction occurs immediately after successful cardiac resuscitation. Our purpose was to determine whether measurement of cardiac troponin I in children with acute out-of-hospital cardiac arrest predicts the severity of myocardial injury. METHODS AND RESULTS This prospective, observational study was performed in the Pediatric Intensive Care Unit (PICU) on 24 patients following arrest, ranging in age from 8 months to 17 years. Troponin measurements were obtained on admission, and at 12, 24, and 48 h. Transthoracic echocardiograms were performed within 24 h after admission. Survival to hospital discharge was 29% (7/24). The mean age was 5.9+/-4.6 years for survivors and 4.2+/-5.3 years for non-survivors. The median (range) duration of cardiac arrest times for survivors was 6 min (3 to 63 min) versus 34 min (4 to 70 min) for nonsurvivors (P=0.02). Survivors received 1.3+/-2.2 doses of epinephrine (adrenaline) compared with 2.9+/-1.6 doses for non-survivors (P=0.02). Only one patient had ventricular fibrillation and defibrillation was unsuccessful. The ejection fraction for survivors averaged 73.2+/-11.2%, but for nonsurvivors only 55.4+/-19.8% (P=0.04). Ejection fraction correlated inversely with troponin at 12 h (r=-0.54, P=0.01) and at 24 h (r=-0.59, P=0.02). Circumferential fiber shortening for survivors was 37.5+/-7.8 and 25.5+/-10.7% for nonsurvivors (P=0.02). It also correlated inversely with troponin (r=-0.46, P=0.03 for survivors and r=-0.65, P=0.01, for nonsurvivors). CONCLUSION After cardiac arrest and resuscitation in pediatric patients, the severity of myocardial dysfunction was reflected in troponin I levels.
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Affiliation(s)
- Paul A Checchia
- Division of Pediatric Critical Care Medicine, Loma Linda University Children's Hospital, Loma Linda, CA, USA.
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Smith A, Grattan A, Harper M, Royston D, Riedel BJCJ. Coronary revascularization: a procedure in transition from on-pump to off-pump? The role of glucose-insulin-potassium revisited in a randomized, placebo-controlled study. J Cardiothorac Vasc Anesth 2002; 16:413-20. [PMID: 12154417 DOI: 10.1053/jcan.2002.125151] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To investigate an optimized glucose-insulin-potassium (GIK) solution regimen as an alternate myocardial protective strategy in off-pump coronary artery bypass graft (OP-CAB) surgery and as a supplement to conventional coronary artery bypass graft (CABG) surgery using cardiopulmonary bypass (CPB). DESIGN Prospective, randomized, placebo-controlled. SETTING Single institution, cardiothoracic specialty hospital. PARTICIPANTS Forty-four patients scheduled for elective multivessel coronary artery surgery using either conventional CPB (n = 22) or OP-CAB techniques (n = 22). INTERVENTIONS Preischemic, ischemic, and postischemic administration of GIK solution was carried out, optimally dosed to ensure nonesterified fatty acid (NEFA) suppression, and supplemented with magnesium, a glycolytic enzymatic cofactor. MEASUREMENTS AND MAIN RESULTS GIK solution therapy reduced plasma NEFA levels (p < 0.001) in OP-CAB surgery and CPB groups but failed to affect the incidence of non-Q wave perioperative myocardial infarction, incidence of postoperative atrial fibrillation, incidence of postoperative infection, reduction in creatinine clearance, or duration of postoperative intensive care unit or hospital length of stay. After adjusting for GIK solution therapy, OP-CAB surgery resulted in significantly less ischemic injury (troponin I >15 microg/L, 19.0% v 91.3%; p = 0.0001) and reduced postoperative infections (14.3% v 43.5%; p = 0.049). CONCLUSION GIK solution therapy achieved NEFA suppression and an insignificant trend toward reduced biochemical parameters of ischemic injury in OP-CAB surgery and CPB groups, but no major clinical benefit (perioperative myocardial infarction, intensive care unit length of stay, or hospital length of stay) was shown after elective CABG surgery in low-risk patients. Compared with CPB, OP-CAB surgery significantly reduced ischemic injury and postoperative infections.
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Affiliation(s)
- Andrew Smith
- Department of Anesthesiology, Royal Brompton and Harefield NHS Trust, London, United Kingdom
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Choragudi NL, Aronow WS, Prakash A, Kurup SK, Chiaramida S, Lucariello R. Does the serum cardiac troponin I level increase with stress test-induced myocardial ischemia? HEART DISEASE (HAGERSTOWN, MD.) 2002; 4:216-9. [PMID: 12147181 DOI: 10.1097/00132580-200207000-00004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To evaluate the sensitivity of the serum cardiac troponin I level in detecting stress test-induced myocardial ischemia, the authors conducted a prospective study including patients admitted for chest pain to the telemetry floor of Our Lady of Mercy Medical Center at Bronx, NY. Consecutive 134 telemetry patients that agreed to participate in this study were included. All of these patients had a nuclear stress test and were divided into various groups based on the prestress test probability of having coronary artery disease. To assess serum cardiac troponin I levels, blood samples were drawn before and after stress testing and compared with the stress test results. Overall, 30 patients (22%) had reversible perfusion defects on stress images, and none (0%) had increased serum cardiac troponin I levels. One patient of 18 patients (6%) in group C with negative stress test results had an elevated serum cardiac troponin I level after the stress test, but none of group A or group B patients had elevated troponin I levels. These data show that serum cardiac troponin I levels do not increase with stress test-induced myocardial ischemia.
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Fellahi JL, Léger P, Philippe E, Arthaud M, Riou B, Gandjbakhch I, Coriat P. Pericardial Cardiac Troponin I Release After Coronary Artery Bypass Grafting. Anesth Analg 1999. [DOI: 10.1213/00000539-199910000-00004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Bertinchant JP, Robert E, Polge A, de la Coussaye JE, Pignodel C, Aya G, Fabbro-Peray P, Poirey S, Ledermann B, Eledjam JJ, Dauzat M. Release kinetics of cardiac troponin I and cardiac troponin T in effluents from isolated perfused rabbit hearts after graded experimental myocardial contusion. THE JOURNAL OF TRAUMA 1999; 47:474-80. [PMID: 10498300 DOI: 10.1097/00005373-199909000-00007] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Few experimental studies report effects of direct contusion on cardiac enzyme release. Cardiac troponins I (cTnI) and T (cTnT) have been shown to be highly sensitive and specific markers of myocardial cell injury. This investigation was designed to determine and compare the acute effects of quantified magnitudes of blunt cardiac trauma upon release of cTnI and cTnT in comparison with creatine kinase (CK) and lactate dehydrogenase (LD). METHODS In 24 rabbit hearts prepared on a standard Langendorff apparatus, myocardial contusion (MC) was produced by a single blow with a ball falling from a predefined height, delivered directly to the surface of the heart. Hearts were divided into control (n = 6) and various quantified impacts: 75 mJoules (mJ) (n = 6), 100 mJ (n = 6), 200 mJ (n = 6). Coronary effluent samples for cTnI, cTnT, CK, and LD were collected at baseline, immediately after MC and 5, 15, 30, 45, and 60 minutes after MC. At the end of experiment, histologic condition was evaluated. RESULTS The anti-cTnI and cTnT MAbs used in the cTnI (Access) and cTnT (Elecsys) assays cross-react with cTnI and cTnT of the rabbit. The time-courses of cTnI, cTnT, CK, and LD were monophasic in form. After MC, all parameters rose significantly compared with baseline and with control group. The maximal release occurred immediately after MC. The area under the cTnI curve and the maximal cTnI concentration were linked to the contusion energy when increased at 200 mJ. Maximal concentrations and areas under cTnT, CK, LD time activity curve were not linked to the contusion energy level and showed no between-energy group differences. The correlation found between maximal cTnI and maximal cTnT concentrations was 0.70 (p = 0.0001). Histologic examination showed cellular disruption and after the more severe impact, the extent of pathologic changes was more extensive. CONCLUSION After graded experimental MC, maximal cTnI concentration and area under cTnI curve increase with the power of impact kinetic energy. Levels of cTnI allow a much higher accuracy in detecting the extent of myocardial injury postMC in comparison with cTnT, CK, and LD in this experimental study. These results should be consistent with the more extensive cTnI release with more severe impact in patients with blunt chest trauma. Furthermore, because specificity and time-course of release, both cTnI and cTnT should have a role in the diagnosis and evaluation of such patients.
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Affiliation(s)
- J P Bertinchant
- Laboratory of Cardiovascular Physiology, University of Montpellier-Nîmes, Nîmes, France
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Haider KH, Stimson WH. Cardiac myofibrillar proteins: biochemical markers to estimate myocardial injury. Mol Cell Biochem 1999; 194:31-9. [PMID: 10391121 DOI: 10.1023/a:1006831217137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Ischaemic heart disease represents the most common of the serious health problems in the contemporary society and acute myocardial infarction (AMI) is the major cause of cardiovascular morbidity and death. The accurate localization and determination of the infarct size and the volume of myocardium at risk at the time of insult is crucial and vital for the choice of treatment. Initially the ischaemic cells are reversibly injured. However, if these changes are not reverted at the earliest, it results in the death of the myocyte. This irreversible myocyte necrosis travels transmurally towards epicardium in the form of a wavefront. A timely intervention during evolving infarct could reduce and delimit the infarct and preserve the left ventricular function. Enzyme analysis and electrocardiography (ECG) along with the clinical history of the patient is still considered to constitute a reliable triad in the diagnosis of myocardial infarction (MI). Efforts have been made to relate infarct size with the serum enzyme level changes without much success. In addition, a number of specialist techniques such as planar radioisotope imaging, single photon emission computed tomography (SPECT), positron emission tomography (PET), Echocardiography, Ventriculography and nuclear magnetic resonance (NMR) imaging have been devised to support diagnosis in the patients who show ambiguous symptoms and ECG findings. However most of these procedures are unavailable to the patients due to economic reasons while others have suffered due to non-availability of ideal radiopharmaceuticals. Major advances have been made in the methods based on immunological techniques to improve the detection and estimation of infarct. These methods are exclusively based upon the production and availability of specific antibodies against intracellular, cardiac specific components.
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Affiliation(s)
- K H Haider
- Faculty of Pharmacy, University of the Punjab, Lahore, Pakistan
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Hobisch-Hagen P, Schobersberger W, Falkensammer J, Luz G, Innerhofer P, Frischhut B, Puschendorf B, Mair J. No release of cardiac troponin I during major orthopedic surgery after acute normovolemic hemodilution. Acta Anaesthesiol Scand 1998; 42:799-804. [PMID: 9698956 DOI: 10.1111/j.1399-6576.1998.tb05325.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Normovolemic hemodilution is a well-accepted method for intraoperative blood salvage. However, some controversy exists concerning the possible risk of myocardial fiber injury as consequence of the reduced oxygen content. Laboratory diagnosis of perioperative myocardial fiber injury is difficult, since biochemical markers are elevated postoperatively due to the surgical trauma. Cardiac troponin I (cTnI) is a new, highly sensitive and specific marker for the detection of myocardial injury. The aim of our study was to investigate whether normovolemic hemodilution in patients with major orthopedic surgery (13 hemodiluted patients, 15 control) induces a release of cTnI. METHODS cTnI as a highly specific and sensitive cardiac parameter, as well as total creatine kinase (CK), creatine kinase isoenzyme MB mass (CKMB mass) and myoglobin were measured after induction of anesthesia, after normovolemic hemodilution, prior to retransfusion of blood components, 3 h after surgery, and on the first and third postoperative days. RESULTS Prior to retransfusion of blood components the hematocrit was decreased to 25.4 +/- 1.2% (mean +/- SEM; range: 18%-34%) in the control group and to 20.2 +/- 0.8% (mean +/- SEM; range: 17%-24%) in the hemodilution group. Total CK, CKMB mass as well as myoglobin concentration increased significantly in both groups, reaching their maxima within the first day of surgery. In contrast, cTnI was below the detection limit of assay (< 0.5 micrograms/L) at any time. CONCLUSIONS We suggest that pre- and intraoperative hemodilution to a hematocrit of approximately 20% by maintaining normovolemia does not induce myocardial fiber injury in patients without preexisting cardiac diseases.
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Affiliation(s)
- P Hobisch-Hagen
- Clinic for Anesthesia and General Intensive Care Medicine, University of Innsbruck, Austria
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Sarko J, Pollack CV. Beyond the twelve-lead electrocardiogram: diagnostic tests in the evaluation for suspected acute myocardial infarction in the emergency department, Part II. J Emerg Med 1998; 16:67-78. [PMID: 9472763 DOI: 10.1016/s0736-4679(97)00244-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
On a daily basis the emergency physician is faced with the difficult task of determining whether or not a patient with acute chest pain is sustaining an acute myocardial infarction. In most cases this is not a straightforward decision. Although observation units are being used more often for chest pain evaluations, many emergency physicians currently admit such patients to an intensive care setting. Because fewer than one-third of emergency department chest pain patients actually suffer an acute myocardial infarction, expensive resources are, in retrospect, used unnecessarily. Conversely, patients who are infarcting, and are inadvertently discharged home from the emergency department, have a worse prognosis than those admitted. This two-part series reviews the newer modalities available that may help the emergency physician arrive at a more accurate diagnosis. This article, Part II, will review the use of biochemical assays of cardiac proteins and discuss the Chest Pain Observation Unit.
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Affiliation(s)
- J Sarko
- Department of Emergency Medicine, Maricopa Medical Center, Phoenix, Arizona 85008, USA
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Ferjani M, Droc G, Dreux S, Arthaud M, Goarin JP, Riou B, Coriat P. Circulating cardiac troponin T in myocardial contusion. Chest 1997; 111:427-33. [PMID: 9041992 DOI: 10.1378/chest.111.2.427] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
STUDY OBJECTIVE Myocardial contusion may induce life-threatening complications, but its diagnosis is difficult. Circulating cardiac troponin T is considered a highly sensitive and specific marker of myocardial cell injury. We investigate the value of cardiac troponin T measurement in the diagnosis of myocardial contusion. DESIGN Prospective study. SETTING Level 1 trauma center. METHODS We prospectively measured circulating cardiac troponin T and performed echocardiography and continuous Holter monitoring in patients who had suffered blunt trauma. Myocardial contusion was diagnosed in patients who fulfilled one of the following criteria: (1) an abnormal echocardiography compatible with myocardial contusion; (2) severe cardiac rhythm abnormalities; (3) severe cardiac conduction abnormalities; and (4) hemopericardium. MEASUREMENTS AND RESULTS One hundred twenty-eight patients were included and myocardial contusion was diagnosed in 29 patients. Patients with myocardial contusion had more severe trauma, experienced more frequently associated thoracic lesions, and had a lower left ventricular ejection fraction area (48 +/- 15 vs 61 +/- 10%; p < 0.001). Elevated circulating cardiac troponin T concentrations were significantly more frequent in patients with a myocardial contusion (31 vs 9%; p < 0.007). An elevated circulating cardiac troponin T concentration (> or = 0.5 microgram/L) was more accurate than MB fraction of creatine kinase (CK) (CK-MB) and CK-MB/CK ratio in the diagnosis of myocardial contusion, as shown by an area under the receiver operating characteristic (ROC) curve (AROC), which was significantly different from 0.50 (AROC = 0.69; 95% confidence interval, 0.56 to 0.80). However, this improvement was not clinically acceptable (sensitivity, 0.31; specificity, 0.91). CONCLUSIONS Circulating cardiac troponin T measurement had a slightly greater diagnostic value than usual biological parameters (CK-MB, CK-MB/CK) in myocardial contusion. Nevertheless, it was concluded that an elevated circulating cardiac troponin T concentration has no important clinical value in the diagnosis of myocardial contusion.
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Affiliation(s)
- M Ferjani
- Département d'Anesthésie-Réanimation, Groupe Hospitalier Pitié-Salpêtrière, Paris VI University, France
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Panteghini M, Bonora R, Pagani F. Rapid and specific immunoassay for cardiac troponin I in the diagnosis of myocardial damage. INTERNATIONAL JOURNAL OF CLINICAL & LABORATORY RESEARCH 1997; 27:60-4. [PMID: 9144029 DOI: 10.1007/bf02827244] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We evaluated a new immunometric assay for the quantitation of cardiac troponin I with the Behring Opus analyzer. All assay steps are performed automatically by the analyzer, the complete procedure requiring 20 min for the first test result. Total precision (coefficient of variation) varied between 5.6% and 13.0%. Comparison with the Pasteur immunoenzymometric assay showed good correlation (r = 0.959), but the Opus assay gave approximately tenfold higher values. Cardiac troponin I was undetectable (< 0.5 microgram/l) in sera from healthy subjects (n = 46), patients with severe skeletal muscle damage (n = 8), and all but 1 patient with chronic renal failure (n = 39). In patients with myocardial infarction (n = 21), investigated for 4 days after onset by frequent sampling, cardiac troponin I peaked at 20.8 +/- 8.1 h after onset with a mean concentration of 164.8 +/- 361.3 micrograms/l, remaining elevated in 89% of patients on the 4th day. In patients with unstable angina (n = 15), cardiac troponin I measurement was valuable in predicting the type of lesion morphology on coronary angiography and the short-term outcome.
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Affiliation(s)
- M Panteghini
- 1st Laboratory of Clinical Chemistry, Spedali Civili, Brescia, Italy
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Bertinchant JP, Larue C, Pernel I, Ledermann B, Fabbro-Peray P, Beck L, Calzolari C, Trinquier S, Nigond J, Pau B. Release kinetics of serum cardiac troponin I in ischemic myocardial injury. Clin Biochem 1996; 29:587-94. [PMID: 8939408 DOI: 10.1016/s0009-9120(96)00105-1] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES The study was undertaken to evaluate the release kinetics of cardiac troponin I (cTn-I) in ischemic myocardial injury. DESIGN AND METHODS The reference range for cTn-I was established by determination of cTn-I in sera and plasma obtained from 622 healthy volunteers (Group 1). cTn-I was compared to: (a) Creatine kinase (CK) MB mass and myoglobin in 12 patients with severe skeletal muscle damage (Group 2); (b) CK-MB activity in 48 patients with myocardial infarction (MI) receiving intravenous thrombolysis (Group 3) (in this group, an additional 43 patients with MI were analyzed separately to characterize cTn-I patterns in thrombolyzed and nonthrombolyzed populations): and in 44 patients with unstable angina (Group 4). RESULTS In Groups 1 and 2, no positive results (> or = 0.1 microgram/L) were obtained. In Group 3, the time-courses of cTn-I were mostly monophasic in form. A pathologic increase occurred earlier in cTn-I than in CK-MB activity (p = 0.0002); the period with increased cTn-I was longer (p = 0.001), the overall sensitivity of cTn-I (93.9%) was higher than that of CK-MB activity (p = 0.00001). cTn-I was more sensitive at admission (p = 0.0004). In additional patients, the cTn-I peak occurred and cTn-I disappeared significantly later in nonthrombolyzed than in the thrombolyzed group. In Group 4, positive tests results were detected in 45% of patients for cTn-I, 16% for CK-MB activity, and 32% for CK-MB mass. CONCLUSIONS The cTn-I assay appears to be ideally suited for the detection of ischemic myocardial injury in complex clinical situations because of its high specificity; cTn-I indicates myocardial tissue damage in patients with unstable angina and is superior to CK-MB activity and mass in this respect.
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Affiliation(s)
- J P Bertinchant
- Department of Cardiology, University Hospital of Nîmes, France
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Chocron S, Alwan K, Toubin G, Kantelip B, Clement F, Kantelip JP, Etievent JP. Effects of myocardial ischemia on the release of cardiac troponin I in isolated rat hearts. J Thorac Cardiovasc Surg 1996; 112:508-13. [PMID: 8751520 DOI: 10.1016/s0022-5223(96)70279-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND The twofold aim of this experimental study was (1) to verify the correlation between the duration of ischemia and concentration of cardiac troponin I and (2) to compare the release of cardiac troponin I with histologic findings. METHODS Experiments were done on 18 rat hearts, which were perfused according to the Langendorff method, immediately after excision in group I (control group) and after immersion for 3 hours (group II) and 6 hours (group III) in St. Thomas' Hospital solution at 4 degrees C. During reperfusion, the release of cardiac troponin I, creatine kinase isoenzyme MB, and lactate dehydrogenase, the recovery of left ventricular pressure, and heart rates were compared among the three groups. After the experiment, three samples of myocardium (left ventricle, right ventricle, and septum) were taken for histologic examination. RESULTS Cardiac troponin I concentration was significantly higher in group III than in groups I and II and in group II compared with group I. Cardiac troponin I concentration increased as the ischemic period increased. The relation between cardiac troponin I release and ischemic duration tended to be linear. Creatine kinase MB and lactate dehydrogenase concentrations did not differ from one group to the other. Left ventricular pressure was not significantly different among the groups. In the control group, no heart had more than 10% of the myocytes affected. One of six hearts in group II and three of six in group III had more than 10% of myocytes affected. CONCLUSION This experimental study showed (1) that cardiac troponin I is an early marker of ischemic injury and (2) that cardiac troponin I concentration increases as the ischemic period increases. Early cardiac troponin I release appears to correlate with the extent of ischemic injury in rats undergoing buffer perfusion.
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Affiliation(s)
- S Chocron
- Department of Thoracic and Cardiovascular Surgery, Saint-Jacques Hospital, Besançon, France
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Etievent JP, Chocron S, Toubin G, Taberlet C, Alwan K, Clement F, Cordier A, Schipman N, Kantelip JP. Use of cardiac troponin I as a marker of perioperative myocardial ischemia. Ann Thorac Surg 1995; 59:1192-4. [PMID: 7733719 DOI: 10.1016/0003-4975(95)00129-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Troponin I is a contractile protein comprising three isoforms, two related to the skeletal muscle and one to the cardiac fibers. Cardiac troponin I (CTn I) is specific, without any cross-reactivity with the other two. Several studies have demonstrated its release after acute myocardial infarction. In contrast, CTn I never has been found in a healthy population, marathon runners, people with skeletal disease, or patients undergoing non-cardiac operations. Thus, CTn I is a more specific marker of cardiac damage than common serum enzymes. It is also more sensitive, allowing diagnosis of perioperative microinfarction and detection of acute myocardial infarction much earlier after the onset of ischemia (4 hours). Using a rapid one-step assay, we measured the release of CTn I in two groups of patients after operation: 20 with calcified aortic stenosis and normal coronary arteries (aortic valve replacement group and control group) and 20 undergoing coronary artery bypass grafting. In the overall population CTn I peaked at hour 6 and practically disappeared after day 5. Mean values were higher in the coronary artery bypass grafting group. In the aortic valve replacement group, a positive correlation was found between aortic cross-clamping time and CTn I, which is a reliable marker of cardiac ischemia during heart operations and can be used to evaluate cardioprotective procedures.
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Affiliation(s)
- J P Etievent
- Department of Thoracic and Cardiovascular Surgery, Saint-Jacques Hospital, Besancon, France
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Abstract
OBJECTIVE To assess various biochemical markers of myocardial damage. METHODS AND RESULTS Before routinely using any test as a biochemical marker of myocardial damage, the published evidence for its diagnostic utility must be critically assessed. Such assessment includes receiver operator curve (ROC) curve analyses, confidence interval estimates of claimed sensitivity and specificity values, and the effects of testing in serial and parallel modes. It is also necessary to establish the test's rule-in (high specificity) and rule-out (high sensitivity) decision thresholds that may vary with time after the onset of symptoms. The spectrum of ischemic heart disease includes acute (sudden death, non-Q- and Q-wave infarctions) and chronic (stable, unstable, and variant angina) conditions. Biochemical markers of myocardial damage are of most value in the diagnosis of acute ischemic heart disease, although increasingly some of these markers are being found to possess a prognostic value in chronic ischemic heart disease. The markers of enzymatic activity include aspartate aminotransferase, creatine kinase (together with isoenzymes and isoforms), and lactate dehydrogenase and isoenzymes. Creatine kinase isoenzyme-2 may also be measured immunologically, and this type of assay is in increasing use both because of its speed and because its blood levels rise earlier than the corresponding activities. The commercially available nonenzymatic markers are myoglobin and troponin T; troponin I is expected to become available in late 1995. While myoglobin is a nonspecific indicator of myocardial damage, its diagnostic value is due to its early appearance in blood. Troponin T is more cardiac specific, but the published data appears to suggest that the cardiac specificity of troponin I is superior. Troponin levels become abnormal at about the same time after the onset of symptoms as mass assays of creatine kinase isoenzyme-2; therefore, they are not useful as early markers of myocardial damage. CONCLUSION The availability of these nonenzymatic markers of myocardial damage must force a reassessment of the continued use of the enzymatic markers. Are they necessary, and if so, which ones should be retained?
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Affiliation(s)
- V Bhayana
- Department of Laboratory Medicine, University Hospital (University of Western Ontario), London, Canada
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