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M Panteghini

Publications and source records attributed to M Panteghini.

At least 37 records · Page 2Linked to original sources
PubMed2000

Determination of decision limits for ACS:systems cardiac troponin I.

The availability of specific markers of myocardial damage has focused attention on the decision limits to be used in clinical practice. These markers can be employed in the diagnosis of myocardial infarction and risk stratification in patients with acute coronary syndromes but no infarction. The measurement of troponin I was undertaken in two 60 patient cohorts with these disease classifications. The best decision level for patients with acute myocardial infarction was found to be 3.1 microg/l; for the detection of minimal myocardial damage the cut-off was equal to the detection limit of the method (0.2 microg/l).

Humans↗
PubMed2000

[The role of biochemical markers of myocardial damage in clinical practice: the diagnosis of infarct and risk stratification. The Intersociety Interdisciplinary Study Group of the ANMCO-SIBioC-SIMeL, Markers of Muocardial Lesions. L'Associazione Nazionale Medici Cardiologi Ospedalieri-Società Italiana di Biochimica Clinica-Società Italiana di Medicina di Laboratorio].

For many years creatine kinase (CK) and CK-MB isoenzymes were used together with the ECG to confirm the presence of myocardial infarction. During the last decade newer cardiac markers have been introduced and immunological test systems developed for their quantification. Among these new markers, a prominent role has emerged for cardiac troponins (T or I). These technological advanced assays have shown greater sensitivity compared to "conventional cardiac enzymes;, thereby identifying patients with small--at times, microscopic--infarcts who would not have met defining criteria for myocardial infarction in an earlier era. Another major advantage shown by both cardiac troponins with respect to "conventional cardiac enzymes" is their ability to predict clinical outcome over a short- or long-term follow-up in patients with acute coronary syndromes, and this appears to be particularly relevant in patients with micronecrosis, who constitute a high-risk subgroup of unstable angina patients. Recently, myoglobin has also been widely applied as a marker. Although lacking in myocardial specificity, it is the earliest marker to show an increase after coronary occlusion. Thus, the combined use of myoglobin and a cardiospecific structural protein such as troponin T or I may prove an attractive strategy for biochemical testing in chest pain patients. With the routine use of these novel cardiac markers, fascinating opportunities are now open in the field of diagnostic classification (making the World Health Organization definition of myocardial infarction obsolete) and risk stratification in chest pain patients; opportunities that were unforeseen in the era of cardiac enzymes. However, the use of these markers has also posed some important questions on: a) the best and most cost-effective diagnostic strategy in chest pain patients; b) the remaining role of cardiac enzymes; c) the therapeutic consequences of a positive test result.

Biochemical Phenomena↗
PubMed2000

Multicenter evaluation of five assays for myoglobin determination.

BACKGROUND: Lacking assay standardization, different myoglobin methods may produce results that differ significantly. METHODS: A multicenter study was carried out to compare the analytical performance of five commercially available assays for myoglobin measurement. Linearity, imprecision, interferences, and method comparison were studied according to NCCLS guidelines, whereas reference values were determined following IFCC recommendations. RESULTS: The BNA and Opus showed relatively high imprecision (all but one total CV >7.4%). Other assays showed lower CVs, but they varied among laboratories, particularly at a normal myoglobin concentration (Access, 6.0-11%; Hitachi, 3.8-5.8%; Stratus, 3.4-6.5%). Results were lower in anticoagulated samples on the Access, in heparin and citrate samples on the Stratus, and in citrate samples on the BNA and Opus, and increased in heparin and EDTA samples on the Hitachi. Use of separator gel produced results significantly lower (P <0.001) on the Hitachi and higher (P = 0.016) on the Opus. Bilirubin, turbidity, and hemoglobin had no effect on evaluated methods, but rheumatoid factor affected the Access. In method comparisons, high correlation coefficients (>/=0.98) were obtained. The Stratus gave higher results; however, the Access and BNA gave the lowest. The following upper reference limits (microgram/L) for men and women, respectively, were obtained: Access, 70 and 52; BNA, 51 and 49; Hitachi, 67 and 58; Opus, 80 and 50; and Stratus, 86 and 63. CONCLUSION: The possibility of high imprecision and marked disagreement among commercial myoglobin assays should be carefully considered in clinical practice.

Humans↗
PubMed1999

Cardiac troponin elevations in chronic renal failure: prevalence and clinical significance.

OBJECTIVES: The aim of the study was investigate the prevalence of abnormal values of cardiac troponin T (cTnT) and cardiac troponin I (cTnI) in patients with chronic renal failure (CRF) and their clinical significance. DESIGN AND METHODS: We investigated the concentrations of cTnT and cTnI in 49 CRF patients without heart disease or diabetes. Cardiac TnT values were measured with a second generation immunoassay and cTnI with two immunoassays with different analytical sensitivity. All CRF patients underwent regular clinical follow-up over a 18-month period. RESULTS: No patients with CRF had elevated values of cTnI when measured with one assay and only 2 patients displayed minimally elevated values with the second assay. In contrast, 23 CRF patients (47%) displayed cTnT concentrations elevated above the upper reference limit. The elevated cTnT values observed were below the values detected in acute myocardial infarction and were not associated with adverse cardiac events during follow-up. CONCLUSIONS: Mildly elevated cTnT concentrations are common in patients with CRF and do not appear to be associated with adverse coronary events.

Adult↗
PubMed1999

Effect of long term simvastatin administration as an adjunct to ursodeoxycholic acid: evidence for a synergistic effect on biliary bile acid composition but not on serum lipids in humans.

BACKGROUND: Stimulated bile acid synthesis preferentially utilises newly synthesised cholesterol, raising the possibility that combination of simvastatin (an inhibitor of cholesterol synthesis) with ursodeoxycholic acid (UDCA; a stimulator of bile acid synthesis) may result in reduced bile acid synthesis and greater enrichment of the pool with UDCA than that achieved with UDCA treatment alone. AIMS: To investigate the effect of simvastatin and UDCA given alone and in combination on serum and biliary lipid and biliary bile acid composition. METHODS: Eighteen patients with primary non-familial hypercholesterolaemia were studied during treatment with simvastatin 20 mg/day, UDCA 10 mg/kg/day, and a combination of the two drugs. Each regimen was given in random order for three months following a three month lead in period. RESULTS: Simvastatin significantly reduced serum low density lipoprotein (LDL) cholesterol but biliary cholesterol concentration remained unchanged. Combination of the two drugs had no synergistic effect on serum cholesterol concentration, but significantly increased the proportion of UDCA in the bile acid pool from 35% during UDCA to 48% during combination treatment (p<0.04). CONCLUSIONS: Results showed that: (1) simvastatin reduces serum LDL cholesterol but has no effect on biliary cholesterol concentration, supporting the concept that newly synthesised cholesterol is not the preferential source for biliary cholesterol; and (2) combination of simvastatin with UDCA has the predicted effect of enhancing the proportion of UDCA in the pool. This effect may be of benefit in the treatment of cholestatic liver diseases.

Adult↗
PubMed1999

Use of biochemical markers in acute coronary syndromes. IFCC Scientific Division, Committee on Standardization of Markers of Cardiac Damage. International Federation of Clinical Chemistry.

This paper presents evidence and suggestions from the IFCC Committee on "Standardization of Markers of Cardiac Damage" (C-SMCD) on the use of biochemical markers for the triage diagnosis of acute coronary syndromes. There is general agreement that both 'early' and 'definitive' biochemical markers of myocardial damage are necessary and that these assays must be available with a turnaround time of 1 h or less. Currently, myoglobin is the marker that most effectively fits the role as an 'early' marker, whereas 'definitive' markers are cardiac troponins. Since the sensitivity of the initial electrocardiogram is only 50% for detecting myocardial infarction, the use of biochemical markers may significantly contribute to the early diagnosis and become relevant when the electrocardiogram is not diagnostic. In addition, new sensitive biochemical markers, particularly the cardiac troponins, are presently the best to detect the presence of minor myocardial cell damage. With regard to this, two decision limits are probably needed for the optimal use of troponins: a low abnormal value suggesting the presence of myocardial damage and a higher value suggesting the diagnosis of myocardial infarction according to traditionally used criteria. Properly designed studies should be performed to establish limits for each commercially available troponin assay. Finally, it is recognized that there is no need for the use of any biochemical marker when the clinical diagnosis is unequivocal, other than for diagnosing reinfarction, estimating the infarct size, and monitoring thrombolytic therapy.

Acute Disease↗
PubMed1999

Proposals from IFCC Committee on Standardization of Markers of Cardiac Damage (C-SMCD): recommendations on use of biochemical markers of cardiac damage in acute coronary syndromes.

This paper presents evidence and suggestions from the IFCC C-SMCD on the use of biochemical markers for the triage diagnosis of acute coronary syndromes. There is general agreement that both 'early' and 'definitive' biochemical markers are necessary and that these assays must be available with a turnaround time of 1 h or less. Currently, myoglobin is the marker that most effectively fits the role as an 'early' marker, whereas 'definitive' markers are cardiac troponins. Since the sensitivity of the initial electrocardiogram is only 50% for detecting myocardial infarction, the use of biochemical markers may significantly contribute to the early diagnosis. New sensitive biochemical markers, particularly the cardiac troponins, are presently the best criterion to detect the presence of small myocardial cell damage. Two decision limits are probably needed for the optimum use of troponins: a low abnormal value suggesting the presence of myocardial damage and a higher value suggesting the diagnosis of myocardial infarction. Additional studies should be performed to establish limits for each commercially available assay. Finally, it is recognized that there is no need for the use of any biochemical marker when the clinical diagnosis is unequivocal, other than for diagnosing reinfarction, estimating the infarct size, and monitoring thrombolytic therapy.

Acute Disease↗
PubMed1999

Proposals from the IFCC Committee on Standardization of Markers of Cardiac Damage (C-SMCD): strategies and concepts on standardization of cardiac marker assays.

The search for sensitive and specific biochemical markers of cardiac damage has resulted in development of methods for the measurement of cardiac markers such as myoglobin, CK-MB mass and the cardiac troponins (cardiac troponin I and cardiac troponin T). There have been new clinical applications of already known markers based on improved, reformulated methods which often depend on advanced technologies. These developments are connected with analytical and interpretative challenges for the laboratory manager and for the clinician. In this situation, it is essential that international professional societies develop comprehensive and carefully elaborated guidelines for the quality management and use of these measurements and their results. Several professional associations have formed committees working on different issues regarding the measurement of biochemical markers of cardiac damage. Recognizing the huge interest in this field and substantial diagnostic relevance of these markers, the IFCC has established the Committee on "Standardization of Markers of Cardiac Damage" (C-SMCD) in 1997 inviting the already operating American and European groups to designate some of their members into the new committee. The task of the IFCC C-SMCD is to coordinate the different activities of the national groups, with preparation of international documents and recommendations under the auspices of IFCC and to initiate various standardization activities. The establishment of consensus/reference methods as well as development of primary and secondary matrix reference materials for markers of cardiac damage are extremely important in order to achieve comparability of test results, thus leading to an effective patient care.

Biomarkers↗
PubMed1999

Biochemical assessment of myocardial damage with new diagnostic tools.

Knowledge of the pathophysiology of acute coronary syndrome has advanced in parallel with awareness of the significant limitations inherent in clinical and electrocardiographic assessment. In the meantime, biochemical assays, long established as a reliable means of detecting World Health Organization-defined myocardial infarction, have improved significantly. Prior of the late 1980s, diagnostic testing for so-called "cardiac" enzymes was not enough sensitive and cardiac-specific. New immunochemical techniques for measuring the mass rather than the activity of an enzyme permit the detection of smaller amounts of the protein markers, and therefore earlier diagnosis is possible. In addition, new laboratory techniques now allow rapid measurement of a wide variety of markers of myocardial cell death. Several serum proteins have recently been introduced and evaluated to determine sensitivity and specificity for detection of acute myocardial damage, including creatine kinase-MB mass measurements, myoglobin, cardiac troponin I, and cardiac troponin T. Cardiac troponin measurement is probably the most clinically effective test, also offering prognostic information to the clinician unavailable by other methods. The diagnostic superiority of these proteins has been established by clinical studies and rigorous statistical comparison with other markers. Furthermore, there is interesting evidence that minor myocardial cell injury revealed by these markers is strictly associated with a high risk of developing major cardiac events during follow-up. This means that these markers should replace existing traditional strategies to guide patient management. Obviously, there will also be financial benefits in terms of reduction in patient episode cost and improvement in decision-making.

Biomarkers↗
PubMed1998

Diagnostic application of CK-MB mass determination.

Recent advances in analytic techniques have increased the diagnostic value of creatine kinase MB (CK-MB), enabling earlier and more sensitive results. The CK-MB mass immunoassays, that utilise the monoclonal anti-CK-MB in conjunction with anti-M or anti-B antibodies, are able to measure accurately small changes during the early hours after myocardial infarction (MI). CK-MB has two main limitations in diagnosing MI neither of which however undermines its established clinical value: CK-MB is not perfectly specific to cardiac injury, with increase occurring also during massive musculoskeletal injury; furthermore, the early release pattern of CK-MB limits its value for the late MI diagnosis. For the foreseeable future evidence is compelling for greater access to rapid testing capabilities in emergency situations, using protocols incorporating CK-MB mass evaluation together with other biochemical markers, i.e. myoglobin and troponins.

Creatine Kinase↗
PubMed1998

Comparison of the diagnostic performance of two rapid bedside biochemical assays in the early detection of acute myocardial infarction.

BACKGROUND: New biochemical markers have been recently proposed as potential aids in the diagnosis of myocardial infarction. Assessment of these markers in real time by near-patient testing would allow more rapid decisions regarding critical therapeutic interventions. HYPOTHESIS: The diagnostic performance of two qualitative, whole blood assays for measurement of myoglobin/creatine kinase (CK)-MB mass (CARDIAC STATus) and cardiac troponin T (TropT) was compared. Their potential in optimizing the rule-in of patients with infarction in order to initiate revascularization therapies was also evaluated. METHODS: A group of 101 patients admitted to the hospital within 12 h from onset of symptoms suggestive of myocardial infarction was studied. A first blood sample was drawn in all patients immediately after admission. In patients not receiving reperfusion therapy (n = 61), three additional samples were also obtained 2, 4, and 6 h later. RESULTS: CARDIAC STATus showed good performance in patients with an admission time > 2 h from onset of pain (diagnostic efficiency, 71-100%). Conversely, TropT was not sensitive enough for acceptable efficiency. In a subset of 39 patients admitted within 6 h who did not meet standard enrollment criteria for thrombolysis, CARDIAC STATus allowed early detection of almost 50% of infarcts, enabling a significant implementation of alternative revascularization therapies. CONCLUSIONS: In patients admitted to the coronary care unit on the basis of case history and clinical examination, CARDIAC STATus assay is more effective than TropT in the early diagnosis of infarction, providing a valuable aid to cardiologists for confirming a suspected infarction rapidly, thus allowing, if indicated, recourse to revascularization therapy in clinically uncertain cases.

Biomarkers↗
PubMed1998

IFCC Committee on Standardization of Markers of Cardiac Damage: premises and project presentation. International Federation of Clinical Chemistry and Laboratory Medicine.

The field of biochemical markers of cardiac damage is in a dynamic state, with new applications continually appearing and new assays and markers being developed. These significant and sudden advancements in the development of new biochemical assays have led however to several analytical and interpretative problems. In this situation, it is essential that a uniform and rigorous outlook be maintained to ensure optimal test utilization. For these reasons, the IFCC Scientific Division recently agreed to establish a Committee on "Standardization of Markers of Cardiac Damage" (C-SMCD), inviting members from the established American and European groups to become members of this Committee. In this presentation, the premises, the issues, and the proposed plan of action of C-SMCD are presented and discussed.

Biomarkers↗