Update on current practice in laboratory medicine in respect of natriuretic peptide testing for heart failure diagnosis and management in Europe. The CARdiac MArker guideline Uptake in Europe (CARMAGUE) study.

BACKGROUND: The European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) initiated the CArdiac MARker Guidelines Uptake in Europe (CAMARGUE) Study to survey if current biomarker testing for heart failure (HF) in Europe is in accordance with up-dated guidelines. METHODS: A web-based questionnaire was distributed to clinical laboratories via European biochemical societies in 2019. Questions covered the type of natriuretic peptide (NP) assays performed, decision limits for HF, and opinion concerning requirement of different thresholds in patients with renal failure or obesity. RESULTS: There were 347 participating laboratories mostly from European countries with 266 offering NP testing. NP testing was increased from 67% to 77% between 2013 and 2019. NT-proBNP remained the preferred biomarker. Recommended decision limits were implemented for BNP (85%) and better focused for NT-proBNP (40%) than in the previous survey. The survey revealed that laboratorians are willing to support the translation of adjusted cut-off values for age, gender and for patients with conditions like renal insufficiency. CONCLUSION: Guidelines stimulate clinical laboratories to offer NP testing with high value for the diagnosis and management of HF, and to present adjusted medical decision limits. Future guidelines should encourage the use of personalized cut-offs for some confounding factors.

How well do laboratories adhere to recommended guidelines for dyslipidaemia management in Europe? The CArdiac MARker Guideline Uptake in Europe (CAMARGUE) study.

BACKGROUND: The CArdiac MARker Guidelines Uptake in Europe Study (CAMARGUE) initiated by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) aims to survey the current use of evidence-based guidelines for dyslipidemia testing in Europe. METHODS: In 2019 a web-based questionnaire was distributed via EFLM National Societies to clinical laboratories in Europe. Questions covered pre-analytics, analytical methods, measurement units, flagging of decision thresholds, and use of decision-enhancing comments. RESULTS: Returns were obtained from 452 laboratories from 28 countries. Most laboratories always use nonfasting blood samples for lipid assays (66%). Lipid profiles are reported in mmol/L by 59% of the laboratories, mainly from 14 countries promoting the use of SI units. Important differences in flagging of decision thresholds were observed, with less than half of the laboratories applying the guideline-recommended LDL cholesterol threshold. Only 17% of the laboratories add an alert comment when familial hypercholesterolemia is suspected and 23% when risk of pancreatitis from hypertriglyceridemia is high. CONCLUSIONS: There are marked differences among laboratories in Europe in terms of pre-analytical, analytical, and post-analytical lipid management that could have an important clinical impact. This relates to different availability of assays or different laboratory practices on reporting and flagging of lipid profiles.

Quantifying atherogenic lipoproteins for lipid-lowering strategies: Consensus-based recommendations from EAS and EFLM.

The joint consensus panel of the European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) recently addressed present and future challenges in the laboratory diagnostics of atherogenic lipoproteins. Total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, and calculated non-HDL cholesterol (=total - HDL cholesterol) constitute the primary lipid panel for estimating risk of atherosclerotic cardiovascular disease (ASCVD) and can be measured in the nonfasting state. LDL cholesterol is the primary target of lipid-lowering therapies. For on-treatment follow-up, LDL cholesterol shall be measured or calculated by the same method to attenuate errors in treatment decisions due to marked between-method variations. Lipoprotein(a)-cholesterol is part of measured or calculated LDL cholesterol and should be estimated at least once in all patients at risk of ASCVD, especially in those whose LDL cholesterol decline poorly upon statin treatment. Residual risk of ASCVD even under optimal LDL-lowering treatment should be also assessed by non-HDL cholesterol or apolipoprotein B, especially in patients with mild-to-moderate hypertriglyceridemia (2-10 mmol/L). Non-HDL cholesterol includes the assessment of remnant lipoprotein cholesterol and shall be reported in all standard lipid panels. Additional apolipoprotein B measurement can detect elevated LDL particle numbers often unidentified on the basis of LDL cholesterol alone. Reference intervals of lipids, lipoproteins, and apolipoproteins are reported for European men and women aged 20-100 years. However, laboratories shall flag abnormal lipid values with reference to therapeutic decision thresholds.

Quantifying atherogenic lipoproteins for lipid-lowering strategies: consensus-based recommendations from EAS and EFLM.

The joint consensus panel of the European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) recently addressed present and future challenges in the laboratory diagnostics of atherogenic lipoproteins. Total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), LDL cholesterol (LDLC), and calculated non-HDLC (=total - HDLC) constitute the primary lipid panel for estimating risk of atherosclerotic cardiovascular disease (ASCVD) and can be measured in the nonfasting state. LDLC is the primary target of lipid-lowering therapies. For on-treatment follow-up, LDLC shall be measured or calculated by the same method to attenuate errors in treatment decisions due to marked between-method variations. Lipoprotein(a) [Lp(a)]-cholesterol is part of measured or calculated LDLC and should be estimated at least once in all patients at risk of ASCVD, especially in those whose LDLC declines poorly upon statin treatment. Residual risk of ASCVD even under optimal LDL-lowering treatment should be also assessed by non-HDLC or apolipoprotein B (apoB), especially in patients with mild-to-moderate hypertriglyceridemia (2-10 mmol/L). Non-HDLC includes the assessment of remnant lipoprotein cholesterol and shall be reported in all standard lipid panels. Additional apoB measurement can detect elevated LDL particle (LDLP) numbers often unidentified on the basis of LDLC alone. Reference intervals of lipids, lipoproteins, and apolipoproteins are reported for European men and women aged 20-100 years. However, laboratories shall flag abnormal lipid values with reference to therapeutic decision thresholds.

Are Heart Failure Management Recommendations and Guidelines Followed in Laboratory Medicine in Europe and North America? The Cardiac Marker Guideline Uptake in Europe (CARMAGUE) Study.

BACKGROUND: The aim of this survey was to investigate how well heart failure (HF) guidelines for use of natriuretic peptides (NPs) have been implemented in laboratory practice in Europe and North America. METHODS: In 2013 and 2014, a web-based questionnaire was distributed via North American and European biochemical societies. Questions covered assay performed, reason for method choice, decision limits for HF, and laboratory accreditation status. RESULTS: There were 442 European Union and 91 North American participating laboratories with response rates of 50% and 64% from major or university hospitals, respectively. NP measurements were offered in 67% of European Union and 58% of North American respondents. N-terminal pro-B-type natriuretic peptide (NT-proBNP) was most widely used in Europe (68%) and B-type natriuretic peptide (BNP) was more commonly used (58%) in North America. The most frequent reason for use of a specific assay was the availability of instruments that measure either NT-proBNP (51%) or BNP (67%). For diagnosis of acute HF, NT-proBNP decision limits were diverse; age-dependent limits based on the 2012 European Society of Cardiology (ESC) recommendations were used in only 17% of European sites and 26% of North American sites. For BNP, the guideline-recommended acute HF decision limit of 100 ng/L was better adhered to in Europe (48%) and North America (57%). Surprisingly, similar decision limits were stated for acute and chronic HF by >50% of respondents. CONCLUSIONS: NP measurement for HF diagnosis was available in >50% of responding laboratories. However, guideline recommended cutoff values for both acute and chronic HF were still implemented in <30% of participating medical centers.

How Well Do Laboratories Adhere to Recommended Clinical Guidelines for the Management of Myocardial Infarction: The CARdiac MArker Guidelines Uptake in Europe Study (CARMAGUE).

BACKGROUND: We undertook an assessment of current use of evidence-based guidelines for the use of cardiac biomarkers in Europe (EU) and North America (NA). METHODS: In 2013-2014 a web-based questionnaire was distributed via NA and EU biochemical societies. Questions covered cardiac biomarkers measured, analytical methods used, decision thresholds, and use of decision-making protocols. Results were collated using a central database and analyzed using comparative and descriptive nonparametric statistics. RESULTS: In EU, returns were obtained from 442 hospitals, 50% central or university hospitals, and 39% from local hospitals from 35 countries with 395/442 (89%) provided an acute service. In NA there were 91 responses (63.7% central or university hospitals, 19.8% community hospitals) with 76/91 (83.5%) providing an acute service. Cardiac troponin was the preferred cardiac biomarker in 99.5% (EU) and 98.7% (NA), and the first line marker in 97.7% (EU) and 97.4% (NA). There were important differences in the choice of decision limits and their derivations. The origin of the information was also significantly different, with EU vs NA as follows: package insert, 61.9% vs 40%; publications, 17.1% vs 15.0%; local clinical or analytical validation choice, 21.0% vs 45.0%; P = 0.0003. CONCLUSIONS: There are significant differences between EU and NA use of cardiac biomarkers. This probably relates to different availability of assays between EU and NA (such as high-sensitivity troponin assays) and different laboratory practices on assay introduction (greater local evaluation of assay performance occurred in NA).

Do laboratories follow heart failure recommendations and guidelines and did we improve? The CARdiac MArker Guideline Uptake in Europe (CARMAGUE).

BACKGROUND: Natriuretic peptides (NP) are well-established markers of heart failure (HF). During the past 5 years, analytical and clinical recommendations for measurement of these biomarkers have been published in guidelines. The aim of this follow-up survey was to investigate how well these guidelines for measurement of NP have been implemented in laboratory practice in Europe. METHODS: Member societies of the European Federation of Clinical Chemistry and Laboratory Medicine were invited in 2009 to participate in a web-based audit questionnaire. The questionnaire requested information on type of tests performed, decision limits for HF, turn-around time and frequency of testing. RESULTS: There was a moderate increase (12%) of laboratories measuring NP compared to the initial survey in 2006. The most frequently used HF decision limits for B-type NP (BNP) and N-terminal BNP (NT-proBNP) were, respectively, 100 ng/L and 125 ng/L, derived from the package inserts in 55%. Fifty laboratories used a second decision limit. Age or gender dependent decision limits were applied in 10% (8.5% in 2006). The vast majority of laboratories (80%) did not have any criteria regarding frequency of testing, compared to 33% in 2006. CONCLUSIONS: The implementation of NP measurement for HF management was a slow process between 2006 and 2009 at a time when guidelines had just been established. The decision limits were derived from package insert information and literature. There was great uncertainty concerning frequency of testing which may reflect the debate about the biological variability which was not published for most of the assays in 2009.

Dioxins and human toxicity.

The term dioxins usually refers to polychlorinated dibenzo-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). As 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) has the highest toxic potential, the toxic potentials of other PCDDs and PCDFs are defined in comparison with it. Human exposure to dioxins can be environmental (background), occupational, or accidental pollution. In the human body, dioxins are in part metabolised and eliminated, and the rest is stored in body fat. People vary in their capacity to eliminate TCDD, but it is also dose-dependent; the elimination rate is much faster at higher than lower levels. The liver microsomal P4501A1 enzyme oxygenates lipophilic chemicals such as dioxins. It is encoded by the CYP1A1 gene. Cytosolic aryl hydrocarbon receptor (AhR) mediates their carcinogenic action. It binds to dioxin, translocates to nucleus and together with hydrocarbon nuclear translocator (ARNT) and xenobiotic responsive element (XRE) increases the expression of CYP1A1.Dioxins are classified as known human carcinogens, but they also cause noncancerous effects like atherosclerosis, hypertension, and diabetes. Long-term exposures to dioxins cause disruption of the nervous, immune, reproductive, and endocrine system. Short-term exposure to high levels impairs the liver function and causes chloracne. The most sensitive population to dioxin exposure are the foetuses and infants.A large number of health effects have been documented in the scientific literature, and they all place dioxins among the most toxic chemicals known to man.

Impact of FXIII-A Val34Leu polymorphism on coronary artery disease in Croatian patients.

Arterial thrombosis is the major reason for severe complications of coronary artery disease (CAD). Recently it has been suggested that the FXIII-A Val34Leu polymorphism, affecting clot stability, provides protection against thrombosis. Results published up to date implicate that there is a significant correlation between geographical area and the Leu34 allele prevalence and that its contribution to arterial thrombosis is different in different populations. The purpose of this study was to determine frequency of Leu34 allele in Croatian subjects as well as to estimate its association with a CAD. FXIII-A Val34Leu genotyping was carried out by real-time PCR method on the LightCycler using melting curve analysis with forward 5'-AACTTCCAGGACCGGCTTT-3' and reverse 5'-ACCCAGAGTGGTGGGGAA-3' primers. The Leu34 allele frequency in studied Croatian subjects was 24.3%. No significant differences were found in the prevalence of FXIII-A Val34Leu genotype or Leu34 allele distribution between studied subjects (P > 0.05). Carriage of the Leu34 allele was not significantly associated with CAD or MI risk reduction (P > 0.05). This is the first report that studies the prevalence of the Leu34 allele frequency in Croatian subjects and our results suggest that possession of the Leu 34 alele does not provide protection against MI.

A pilot survey of the use and implementation of cardiac markers in acute coronary syndrome and heart failure across Europe. The CARdiac MArker Guideline Uptake in Europe (CARMAGUE) study.

BACKGROUND: Guidelines on preferred cardiac marker strategies for investigation of patients with acute coronary syndromes (ACS) are available from the laboratory medicine and cardiology communities. Therefore, implementation of these guidelines into daily clinical practice should be a joint effort of laboratory specialists and clinicians. This was investigated in this survey. METHODS: A pilot study was performed sponsored by the European Federation of Clinical Chemistry and Laboratory Medicine. A link to an online questionnaire was e-mailed to 990 laboratories from eight European countries in May 2006. The requested information included tests performed, clinical protocol development, and reference limits. RESULTS: We obtained a total of 220 responses. Out of these, 208 responses (95%) were from hospitals that provide 24-h admission of patients. The suggested turn-around-time (<60 min) was apparently met by >88% for cardiac troponin T/I and for CK-MB mass. The majority of the laboratories derive their decision limits from kit inserts provided by the manufacturers. The results revealed a worrying fact that external quality assessments are not used in all testing. CONCLUSIONS: Our survey demonstrated that cardiac troponin is the preferred biomarker for the diagnosis of ACS. Half of the participants had written protocols, mostly as a result of collaboration between laboratorians and clinicians.

C-reactive protein gene polymorphisms affect plasma CRP and homocysteine concentrations in subjects with and without angiographically confirmed coronary artery disease.

Human C-reactive protein (CRP) is a reactant involved in the acute phase response and one of the many molecular factors involved in pathogenesis of coronary artery disease (CAD). CRP gene variants potentially mediate CRP plasma concentrations and the development of CAD. 220 Croatian subjects with angiographically confirmed CAD and 132 control subjects were included in the study. CRP gene polymorphisms 1059G/C and -717G/A were determined by RFLPs, using MaeIII and KspI endonuclease, respectively. Plasma concentrations of CRP and homocysteine were determined by immunoturbidimetry and FPIA, respectively. CRP 1059G/C gene variants were significantly associated with CAD (OR = 0.50; 95% CI = 0.27, 0.94; P = 0.032). Wild GG genotype and rare allele C carrier genotypes were 184 and 22 in CAD(+) group, and 101 and 24 in CAD(-) group, respectively. Multivariate analysis with age, gender, BMI, smoking status, hypertension and diabetes as covariates showed that 1059C carriers had lower CRP concentrations in CAD(-) (P = 0.010) and CAD(+) subjects (P = 0.028). This allele was also significantly associated with lower plasma homocysteine concentrations in both groups (P = 0.018 for CAD(-) and 0.002 for CAD(+). There was no significant difference between CAD(+) and CAD(-) subjects in absolute frequencies for CRP -717A/G gene variant, but multivariate analysis showed that carriers of the rarer G allele had significantly higher CRP plasma concentrations in CAD(-) subjects (P = 0.031) and higher homocysteine concentrations in CAD(+) group (P < 0.001). Atherosclerosis is an inflammatory disease resulting from different genetic and environmental factors. Results presented here support the contribution of CRP genetic variations in the development of CAD.

Association of angiotensin-converting enzyme insertion-deletion polymorphism with preeclampsia.

The aim of this study was to determine if insertion-deletion polymorphism of angiotensin-converting enzyme is a risk factor for the development of preeclampsia. Sixty women with preeclampsia and 50 normotensive pregnant women were included in this study. Preeclampsia was defined as blood pressure >140/90 mmHg in a previously normotensive women with proteinuria >300 mg/L in a 24-hours. Twelve women also had preeclampsia in previous pregnancy. The genotyping of polymorphism in the intron 16 of the angiotensin-converting enzyme was performed by the polymerase chain reaction followed by the agarose electrophoresis. The patients were divided into three groups according to the presence (I) or absence (D) of insertional polymorphism (II, ID, and DD). Genotype distribution and allele frequencies were compared by Mantel-Haenszel chi2 testing. The frequency of DD genotype was not significantly higher in women with preeclampsia (26/60) than in the control group (14/50, p=0.096). The D allele frequency was significantly higher in 17 women with preeclampsias who required delivery before 34 weeks of pregnancy (0.735), than in 43 women in whom obstetric complications took place after 34 weeks of pregnancy (0.56, p=0.036). The D allele frequency was 0.83 in women having recurrent preeclampsia, i.e. significantly higher compared with women, who were for the first time, experienced preeclampsia (0.57, p=0.013). This study showed a significantly positive association between D allele frequency and risk of recurrent preeclampsia and preterm delivery before 34 weeks of pregnancy. The deletion genotype could be an important contributing factor for an early onset and recurrent preeclampsia.

[Influence of gene polymorphisms in adhesion molecules and inflammation mediators as risk factors for coronary heart disease and myocardial infarction--an overview]. / Utjecaj polimorfizama gena za adhezijske molekule i medijatore upale kao cimbenika rizika za koronarnu bolest srca i infarkt miokarda.

Cardiovascular diseases are influenced by inheritance and environmental factors. There is a growing number of genetic variants, which may be included in the genesis and development of coronary artery disease (CAD). CAD or ischemic heart disease is a set of clinical symptoms caused by inadequate transport of oxygen because of changes in coronary circulation leading to myocardial ischemia. The most common cause of CAD is atherosclerosis of coronary arteries, which primarily narrows or occludes the lumen of coronary arteries or stimulates thrombosis. In this review, the role of the most important polymorphisms in adhesion molecules, intracellular adhesion molecule-1, integrins alpha2beta1 and beta3, E-selectin as well as of inflammation mediators, tumor necrosis factors alpha and beta, in the development of CAD risk and myocardial infarction is discussed. A review of different genotyping results provides an insight into the mechanisms responsible for the disease risk and helps detect the key sets of predictive markers that are clinically informative.

[Quality in health care]. / Kvaliteta zdravstvene skrbi.

Quality in health care is the basic requirement in each medical intervention based on good medical praxis and principles of medicine based on scientific evidence. However, health systems and medical personnel in health insitutions in Europe as well as other parts of the world are nowadays confronted with public requirements for better care and more quality in health system, less risks and undesirable outcomes of medical interventions. Based on recent results of investigations on sources for mistakes it was persumed that it might be the consequence of more complex technologies used in diagnosis and treatment, as well as shortage of time between new development and application in medical practice, the lack of information technologies needed for follow up of interventions, ageing of population and more chronicaly ill patients etc. Therefore, systematic approach in implementation of quality improvement programs is first priority for any health system which is oriented to patients needs and satisfaction. In this rewiev article the basic terms and methods used for quality improvement in health care is presented, including quality assessment, quality control and management of quality.

[Lipoprotein lipase--physiological and pathophysiological roles of this gene variant in Croatian population]. / Lipoprotein lipaza--fizioloske i patofizioloske uloge te genske varijante u Hrvatskoj populaciji.

Lipoprotein lipase is a key enzyme in hydrolysis of triglyceride and exchange of lipids between lipoproteins in circulation. It has also been found for lipoprotein lipase to play key roles in number of pathophysiological conditions. Over hundred different lipoprotein lipase gene variants have been described in the literature. Lipoprotein lipase gene has been observed as a key factor involved in the pathogenesis of hypertriglyceridemia, coronary heart disease and pancreatitis. In Croatian population the following gene variants have been described: -93T/G, D9N, V108V, N291S, S447X, Pvu II i Hind III. The most important finding was the first mutation W86R which caused familial hypertriglyceridemia. The investigation of mutations and polymorphisms may open the new directions for molecular diagnostics of hypertriglyceridemia and help us recognize the new mutations. Differential diagnosis of hypertriglyceridemia and medical practice involved in their prevention and treatment may be improved by knowing the frequency of lipoprotein lipase gene variants as well as their influence on lipid profile.

Association of two genetic variations of lipoprotein lipase, S447X and Hind III, with coronary artery disease and hypertriglyceridemia.

This study was performed to assess the effect of the S447X and Hind III lipoprotein lipase gene polymorphisms on development of coronary artery disease and hypertriglyceridemia. The study included 132 patients and 98 healthy control subjects of Croatian descent. The lipoprotein lipase S447X polymorphism was associated with coronary artery disease and hypertriglyceridemia, as indicated by the lower frequency of S447 allele in the patient group (p = 0.005) and odds ratio (O.R = 0.40, p = 0.006). The patient and control groups also showed a significant difference in the distribution of Hind III/S447X genotype combinations (p = 0.013). There were no significant associations with lipid parameters for any genotype or genotype combination in the patient group. Frequencies of the S447X polymorphism and S447X/Hind III combinations differed between the CAD/TG and control group, thus these polymorphisms may be associated with CAD and hypertriglyceridemia.