High-sensitivity Point of Care Testing (POCT) methods for Cardiac Troponins: analytical features and clinical relevance.
A consensus document by the Study Group on Cardiac Biomarkers from the Italian Society of Biochemical Chemistry (SIBioC) and the European Ligand Assay Society (ELAS)

AUTHORS

ABSTRACT

The purpose of this paper is to discuss in detail the analytical features and clinical relevance of the high-sensitivity cardiac troponin I (hs-cTnI) POCT methods in patients suspected of having NSTEMI, especially taking into consideration the possible application of the recommendations reported by the international guidelines in the clinical practice. In the first part, we will describe the analytical performance and clinical results of the new POCT methods for the measurement of hs-cTnI, in comparison with those of hs-cTnI methods used in clinical laboratories with the most common automated analytical platforms, and those of non high-sensitivity POCT. In the second part, we will discuss the 2023 recommendations of the IFCC Committee on the Clinical Application of Cardiac Biomarkers (IFCC C-CB) document, with the aim to provide some useful recommendations on educational paths to implement the use of POCT hs-cTnI methods in clinical practice. In the last part, we will describe some possible technological developments of POCT hs-cTnI methods, with the goal to bring these tests even “closer” to the patient and/or to continuously monitor the circulating biomarker levels.

BACKGROUND
Troponins I (cTnI) and T (cTnT), measured with high-sensitivity methods (hs-cTnI and hs-cTnT), are the first-choice biomarkers recommended by all national and international guidelines for the identification of myocardial damage and for the differential diagnosis of acute coronary syndromes (ACS) in patients admitted to the Emergency Department (ED) (1-4). In the last 10 years, their use has allowed to progressively reduce the time to diagnosis of myocardial infarction (MI) from 6-12 hours to less than 3 hours in most patients (2,5,6). In particular, the 2020 European Society of Cardiology (ESC) guidelines recommended the fastest clinical algorithms with a blood sampling on admission and the second one after 1 or 2 hours (0-1h or 0-2h) for the diagnosis of non ST-segment elevation MI (NSTEMI) (2). This recommendation is based on data suggesting that these algorithms (especially the 0-1h algorithm) allows to reach the diagnosis in the shortest possible time, particularly in ruling out MI. This would reduce the time spent in the ED (2).
However, other recent consensus documents and guidelines have observed that faster algorithms for the diagnosis of NSTEMI can be effectively implemented only in hospitals where the ED works in close connection with the clinical laboratory, enabling a turnaround time (TAT), i.e., the time of measurement, <60 minutes (2,3,7).
Many authors have suggested that the development of Point-Of-Care-Testing (POCT) methods for cTnI and cTnT with high analytical sensitivity could represent a fundamental progress because these methods could further reduce the TAT of cTnI and cTnT measurement in patients with NSTEMI (7-11). Furthermore, the
hs-cTn POCT methods could allow diagnosing NSTEMI at home, in an outpatient clinic or on the ambulance (7-11). In the last 5 years, the analytical characteristics of some hs-cTn POCT methods have been made available, and some preliminary clinical results in patients with suspected STEMI-ACS obtained adopting these POCT systems have also been published (Table 1) (7,8-15). Furthermore, in January 2023, the IFCC Committee on Clinical Applications of Cardiac Bio-Markers (IFCC C-CB) issued a document providing an in-depth analysis of the analytical characteristics and the clinical relevance of these new hs-cTnI methods (12).
The purpose of this consensus document is to discuss in detail the analytical features and clinical relevance of these hs-cTnI POCT methods in patients suspected of having NSTEMI (7-11), especially taking into consideration the possible application of the recommendations by the 2023 IFCC C-CB document in the clinical practice (12).
In the first part, the analytical performance and clinical results of the new POCT methods for the measurement of hs-cTnI, in comparison with those of hs-cTnI methods used in clinical laboratories with the most common automated analytical platforms, will be described, together with those of non high-sensitivity POCT. In the second part, the recommendations of the IFCC C-CB document will be discussed (12) providing recommendations on educational paths to implement the use of POCT methods for the measurement of hs-cTnI in clinical practice. The last part, will consider some possible technological developments of POCT methods to measure hs-cTnI, with the goal to bring these methods even “closer” to the patient and/or to continuously monitor the circulating biomarker levels.

ANALYTICAL PERFORMANCE OF hs-cTnI POCT METHODS AND CLINICAL DATA
General considerations
The IFCC C-CB document (11) defines as POCT all laboratory methods that can be employed close to the patient, carried out by personnel not belonging to a laboratory. POCT methods can be divided into 3 classes (11).
The first class includes all laboratory instruments that can also be used in close proximity to the patient, for example in an acute care unit: these tools can be very similar to those commonly used in hospital clinical laboratories. The second class includes the so-called benchtop or desktop instruments, which can be used both in the central laboratory and in a decentralized and dedicated position close to the patient. Finally, the third class includes portable instrumentation that is easily transported by a single person or using a special trolley (11). In this document, the term “POCT methods for measuring hs-cTnI”, is used only for the third class of POCT instruments, unless otherwise specified. These instruments can be easily transported and used close to the patient, either at home or in an ambulance (or other vehicle, such as a ship or aircraft) or in a decentralized first aid clinic.
In 2018, the document of the American Association for Clinical Chemistry (AACC) and International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) (16) established the quality specifications for high-sensitivity (hs) methods for cardiac troponins measurement. This document has established two criteria to define hs-cTn methods. The first criterion is the ability to measure the 99th percentile of the biomarker distribution in the reference population (99th percentile upper reference limit – URL) with a coefficient of variation (CV) equal to or less than 10%. The second criterion is that these methods must be able to measure the cTn circulating levels corresponding to the limit of detection (LoD) in the majority of normal adult subjects, both in women and men. In particular, to estimate the 99th URL percentile with a 95% confidence limit, it is necessary to calculate this value using a reference population including at least 300 healthy men and 300 healthy women (5,16-18). Indeed, women have on average lower circulating biomarker levels than men of the same age (by about 30-50%), therefore it is essential to demonstrate that the hs-cTnI and hs-cTnT methods are effectively able to measure the circulating levels of the biomarker in the majority of healthy women in the reference population (5,16-18). The compliance of these two criteria requires a considerable effort by manufacturing companies (5). Actually, the measurement of the biomarker in the majority of healthy women, requires that methods can display a sensitivity values (LoD) ​​<3 ng/L (5). Only in the last 10 years some hs-cTnI and hs-cTnT methods have been introduced that can satisfy the quality specifications recommended by international guidelines (5,15-25).
Even more difficult was the methodological path to develop hs POCT methods for the measurement of cTnI and cTnT (7,8). The IFCC C-CB Panel papers, published in 2019 (10) and 2023 (12), respectively, summarize the analytical characteristics and clinical results of the POCT methods for measuring cTnI and cTnT, which were commercially available between 2015 and 2019 and which cannot be considered hs methods. Table 1 summarizes the analytical characteristics of the 3 POCT methods for cTnI currently available in Italy, which demonstrate the analytical performance required for hs-cTnI methods, with LoD values ​​(range 1-3 ng/L) and 99th percentile similar to those of the hs-cTnI methods of the most common automated platforms used in clinical laboratories in Italy (7,8,13-15). These POCT methods for hs-cTnI are based on immunoassay systems similar to those used in automated platforms.

The analyzers

PATHFAST POC hs-cTnI method
The PATHFAST POC hs-cTnI method uses the bench-top immunometric analyzer called PATHFAST™ (PHC Europe B.V., Nijverheidsweg, The Netherlands; distributed in Italy by GEPA, Bollate, Milano), which combines the technologies of chemiluminescence (CLEIA) for signal detection (enzyme alkaline phosphatase bound to anti-cTnI monclonal antibodies) and magnetic migration (called Magtration®) for the separation of the bound phase, using antibodies marked by magnetic particles (13,26). The instrument requires a volume of 100 mL of both whole blood, plasma or serum; up to 6 samples can be analyzed simultaneously. In addition to hs-cTnI, the instrument can also measure other analytes: myoglobin, N-terminal pro-B-type natriuretic peptide (NT-proBNP), hs-C-reactive protein, creatine kinase-MB, and presepsin (26).
Sorensen et al. (13) evaluated the analytical performance of the PATHFAST POC hs-cTnI method based on the STARD 2015 guidelines (27), reporting that level of blank (LoB) and LoD values are 1.5 ng/L and 2.9 ng/L, respectively. The imprecision is <20% CV for values ≥3 ng/L and ≤10% CV for values >10 ng/L, respectively. In a cohort of 474 healthy adults (238 men and 236 women) with a median age of 48 years [interquartile range (IQR) 21-74 years], the 99th percentile URL was 21.1 ng/L in women and 27.0 ng/L in men, respectively (13). In the same cohort, 77.8% of the enrolled individuals had a value greater than LoD (67.8% of women and 84.9% of men). Finally, the same Authors (13) evaluated the diagnostic accuracy of the PATHFAST POC hs-cTnI method using a 0-1h algorithm in 669 patients admitted to the ED with suspected NSTEMI from July 2013 to July 2016, according to the 2015 ESC guidelines (28). The clinical algorithm was calculated in this first cohort of patients considering the value of PATHFAST POC hs-cTnI method measured on admission to the ED and after one hour in those suspected of NSTEMI. The validated algorithm should assume a concentration of hs-cTnI
<4 ng/L at admission or a delta value <3 ng/L between 0 to 1 hour in order to rule out NSTEMI, with a negative predictive value (NPV) of 99.7% [95% confidence interval (95%CI) 98.1-100]. For the rule in of NSTEMI, a hs-cTnI concentration ≥90 ng/L or a difference in the biomarker concentrations (delta) ≥20 ng/L from admission to 1h were identified as cut-off value with a positive predictive value (PPV) of 86.5% (95% CI, 77.6-92.8). As observed by the Authors (13), these clinical results are fully comparable with those reported with hs-cTnI methods using the most common automated platforms (2-5,12).

POCT method Quidel TriageTrue TMHigh Sensitivity Troponin I Tes
The immunofluorescence system called “Quidel TriageTrue TMHigh Sensitivity Troponin I Tes” (REF 97600EU; manufacturer: Quidel Corporation Headquarters, San Diego, CA 92121, USA) is a POCT method meeting the requirements for hs-cTnI methods (7,12,14,16,29). The TRIAGE hs-cTnI POCT method can use a few drops of whole blood or EDTA plasma for biomarker measurement with the Triage® MeterPro instrument, which has the weight of a cell phone (29). The manufacturer declares that LoB, LoD and limit of quantification (LoQ) at 10% using EDTA plasma samples have the following ranges of values: 0.0-0.4 ng/L,
0.7-1.6 ng/L and 4.4-8.4 ng/L respectively, with a linearity range from 1.0 ng/L to 1000 ng/L (29). 99th percentile URL values ​were calculated in a reference population including 789 apparently healthy adults (391 women and 398 men): total population 20.5 ng/L (90%CI, 14.6-28.7), women 14.4 ng/L (90%CI, 13.1-28.7), men 25.7 ng/L (90% CI, 18.3-37.6).
In 2020, Boeddinghaus et al. (14) evaluated the value of LoB, LoD and LoQ 10% CV of this POCT method obtaining values ​of 0.6 ng/L, 1.5 ng/L and 2.1 ng/L, respectively, using samples of EDTA plasma, and 0.6 ng/L, 1.7 ng/L and 2.8 ng/L respectively using whole blood samples. Furthermore, these Authors compared the clinical performance of the POCT TRIAGE hs-cTnI method with those of the Architect hs-cTnI and Elecsys hs-cTnT methods, using the specific 0-1h algorithm in 1261 patients (mean age 60 years, IQR 47-73 years; 32% women), admitted to the ED with symptoms lasting from <12 hours and suggestive of MI (and a final MI diagnosis in 14%) (14). In this study, the area under the curve (AUC) value at time 0 for the POCT TRIAGE hs-cTnI method was 0.95 (95%CI, 0.93-0.96) and therefore, comparable with that of hs-cTnT method (AUC 0.94; 95%CI: 0.93-0.96; p=0.213), and higher than the automatized
hs-cTnI method (AUC 0.92; 95% CI: 0.90-0.93; p<0.001). A POCT TRIAGE hs-cTnI method value <3 ng/L at ED admission was able to identify 45% of low-risk patients with a NPV of about 100% (95%CI, 99.4-100%), while a concentration >60 ng/L identified high-risk patients with a PPV of 76.8% (95%CI, 68.9-83.6%). In addition, the 0/1 h algorithm was able to rule-out MI in 55% of patients (NPV 100%; 95%CI, 98.8-100%), and confirm MI in 18% of patients (PPV 76.8%; 95%CI, 67.2%-84.7%) (14). Finally, patients judged to be at low-risk (i.e. ruled-out MI) showed adverse events in 0% of cases at 30 days and 1.6% after 2 years (14).

Siemens POC Atellica ® VTLi hs-cTnI method
The POCT method called “Siemens POC Atellica ® VTLi hs-cTnI” adopts an innovative system that uses Magnotech® type biosensors to separate the cTnI fraction, bound by antibodies to magnetic beads, from the free fraction, and detects the signal using the imaging technique called Frustrated Total Internal Reflection (FTIR) (30). This method uses the “Atellica® VTLi Patient-side Immunoassay Analyzer” instrument, which has the dimensions of a hand-held instrument (length
25 cm, height 8.5 cm, width 8.5 cm) (Siemens Healthineers, Erlangen, Germany; distributor in Italy: Siemens Healthcare s.r.l., Milan) (30). This hs-cTnI POCT system uses a drop (about 30 μL) of whole blood or heparinized plasma, which is introduced into the reaction chamber. Red blood cells are retained by a specific membrane. After the antigen-antibody reaction, which takes place on the sensor surface, the unbound antigen is rapidly removed by a magnetic field oriented in such a way as to rapidly remove the unbound fraction from the sensor surface (i.e., the Magnotech® technique) (30,31). The reported TAT is <8 minutes, and the LoD declared by manufacturer is 1.2 ng/L for heparinized plasma sample and 1.6 ng/L for whole blood, (30).
In 2021, Apple et al. (15) evaluated the analytical performance and calculated the 99th percentile URL of this new Atellica® VTLi POCT method for hs-cTnI. The calculated LoD value was 1.24 n/L, while the LoQ 10% CV was 6.7 ng/L. The authors enrolled 693 apparently healthy adults (363 men, 330 women, aged 18-91 years, median 39 years), with normal levels of glycated hemoglobin, NT-proBNP, and estimated glomerular filtration rate. The calculated 99th percentile URL values ​​were: in the whole population, 23 ng/L (90% CI 20-32 ng/L); for men, 27 ng/L (21-37 ng/L); for women, 18 ng/L (9-78 ng/L) (15). The percentage of subjects with hs-cTnI POCT values greater than the LoD value were: whole population: 83.7%; men: 87.3%; women: 79.7%. Therefore, the Atellica® VTLi POCT method for hs-cTnI measurement demonstrates the analytical characteristics and performance recommended for high-sensitivity s methods (12,16).
In 2022, Apple et al. (32) evaluated whether the POCT Atellica VTLi hs-cTnI method was able to identify patients at low risk of MI among those admitted to the ED with symptoms suggestive of NSTEMI in two different studies: Safe Emergency Department Discharge Rate (SEIGE) in the USA, and Suspected Acute Myocardial Infarction in Emergency (SAMIE) in Australia. A total of 1 086 patients (8.1% with a final diagnosis of MI, 19% with a diagnosis of myocardial injury) were enrolled in the SEIGE study, and 1 486 patients in the SAMIE study (5.5% with final diagnosis of MI and 6.1% with diagnosis of myocardial injury), respectively. A rule-out cut-off <4 ng/L was first calculated on the blood sample at admission (time 0) with a 99.5% NPV (95%CI, 97.2-100) and a sensitivity of 99.0% (95%CI 93.8-100), using data from the SEIGE study (32). This cut-off value was then validated with plasma samples from the SAMIE study finding a sensitivity of 98.8% (95%CI, 93.3-100), and NPV of 99.8% (95%CI, 99.1-100). Some patients (17.8% in the SEIGE study and 41.8% in the SAMIE study) were defined as low-risk because of hs-cTnI values <LoD at ED admission. The number of adverse events (MACE) after 30 days in low-risk patients was 0.1% in SEIGE and 0.8% in SAMIE studies. Finally, the Authors compared the AUC of the POCT Atellica VTLi hs-cTnI method with those of two other hs-cTnI methods (i.e., Architect
hs-cTnI method, Abbott Diagnostics and Access hs-cTnI, Beckman Coulter Diagnostics), obtaining AUC values non-significantly different between the POCT method and these automated platforms (32). The Authors conclude that the POCT Atellica VTLi hs-cTnI method allows a valid, rapid and safe exclusion of MI in patients admitted to the ED (32).

USE OF hs-cTnI POCT METHODS IN CLINICAL PRACTICE: GUIDELINES AND RECOMMENDATIONS
In January 2023, the IFCC C-CB Committee, issued the document entitled: “Cardiac troponin measurement at the point of care: educational recommendations on analytical and clinical aspects by the IFCC Committee on Clinical Applications of Cardiac Bio-Markers (IFCC C-CB)”. The main purpose of this document is to provide some practical educational pathways and technical information on the analytical characteristics and clinical relevance of POCT methods for cardiac biomarkers (12). In particular, the document contains 7 recommendations on the most appropriate use, the analytical performance and results of the most recent clinical studies obtained using hs-cTnI POCT methods. Overall, hs-cTnI POCT methods should be employed to diagnose NSTEMI, both in the ED and in other clinical settings, because they improve diagnostic efficacy and reduce waiting times, thereby also decreasing healthcare costs (12). This goal can be achieved by implementing a diagnostic pathway that includes hs-cTnI POCT methods using 0/1 h rapid diagnostic algorithms, because patients at low risk of NSTEMI can be identified more quickly in this way (11,12,14,32).
The integration of POCT methods into clinical practice of the healthcare system, is neither simple nor cost-free. Indeed, the instrument must be positioned near to the patient, and the POCT method must be integrated in the workflow of the clinical laboratory [including the Laboratory Information System (LIS)], which covers the quality control and the maintenance of the instrument. This integration must require specific training of the personnel who will be in charge of the measurement, because these personnel often come from the medical-nursing area rather than the clinical laboratory (12).
The first specific recommendation of the IFCC C-CB document underlines the clinical relevance of hs-cTnI POCT methods and the achievement of specific clinical goals by implementing these methods in the diagnostic pathway of patients with suspected ACS (11,12). The hs-cTnI measurement with POCT methods in clinical practice could impose a significant economic burden for the Healthcare System, considering that the measurement of hs-cTnI or hs-cTnT is among the most requested laboratory tests in the ED, as well as in medical and surgical intensive care units for both adults and children (11,12,23,33-36). Indeed, besides the costs of the instrument and its implementation in the clinical path, the cost of examining the single sample with hs-cTnI POCT methods is much higher than the one of the sample measured with hs-cTnI methods performed with the most common automated platforms (on average, 5 euros for each test in italy). For this reason, the IFCC C-CB 2023 document recommends that the cost/benefit of the routine use of hs-cTnI POCT methods in the clinical pathway in Emergency/Urgency departments and intensive care units must be carefully calculated before its implementation in clinical practice (12). Theoretically, the most accurate way to calculate the cost/benefit of employing hs-cTnI POCT methods in the clinical pathway is the development of an ad hoc study aimed at highlighting the positive clinical impact of the new test on patient flows in the ED and in critical wards using rapid clinical algorithms (≤1 h) (11,12).
Currently, only the study by Apple et al. (16) was specifically designed to evaluate both the diagnostic accuracy and the clinical utility of the hs-cTnI POCT method in two different clinical settings. This study verified that the POCT method using a rapid algorithm with a single blood draw on admission, allows for a more rapid exclusion of low-risk patients (i.e., those who have a low probability of MI), leading to a reduction of crowding in the ED compared to the classic hs-cTnI methods used by the clinical laboratory in USA and Australia. As observed in the IFCC C-CB document (12), given the significant disparity of conditions between the health services in different countries, further studies are needed to confirm these results (16).
It is not sure that using the same hs-cTnI POCT method and the same diagnostic algorithm it will be possible to achieve the same diagnostic efficiency and effectiveness and the same improvement in the flow of patients from the ED to the clinical departments or the rapid discharge in different clinical settings. Indeed, the second recommendation of the IFCC C-CB document (12) emphasizes that the use of hs-cTnI POCT methods should be validated before its definitive implementation and should be carried out by the same personnel who will actually perform these tests in clinical practice.
Other recommendations of the IFCC C-CB document (12) deal with the evaluation and monitoring of possible problems during the clinical use of hs-cTnI POCT methods, such as: pre-analytical and analytical (recommendation 3), possible interference and difficulty of interpretation of clinical results (recommendation 4), need for the use of a validated information system and automatic quality control of all procedures and reporting of results (recommendations 5 and 6). Recommendation 7 takes into consideration the possibility, very common in clinical practice, that the same clinical institution employs different methods for measuring hs-cTnI and hs-cTnT, both POCT and non-POCT, which will demonstrate different analytical performances and 99th percentile URL values, which can lead to problems in the interpretation of the results by clinicians (2-7,10,11,17,18,36,37).

FUTURE PERSPECTIVES
The immunometric methods for cTnI and cTnT are recommended by all international guidelines as the reference methods for the diagnosis, treatment and evaluation of cardiovascular risk since 2000 (1-5,16). However, only recently, some immunometric systems with high sensitivity analytical performance have been used for the development of POCT methods, and these tests are now commercially available worldwide (13-15), while other POCT methods are not yet available in Italy (38,39). Furthermore, other techniques that do not use the immunometric system to measure cardiac troponins have been described (40). Some of these innovative techniques, both immunometric and non-immunometric, are very interesting because they allow the detection of cardiac troponin using very interesting tools such as smartphones (39) or even wearable systems (so-called “live test”) (40,41), which could allow the measurement of the biomarker by transdermal route (40).
In 2022, Titus et al. (40) described the analytical performance and some preliminary clinical results of an innovative POCT method using the Attenuated Total Reflectance (ATR) spectrometry technique to measure cTnI levels, not only in blood samples, but also through the skin, using specific sensors that provide the result in about 5 minutes. The authors miniaturized the instrument in order to make it wearable and able to measure the biomarker through the skin (40). The instrument measures cTnI levels in a linear concentration ranging from 2.5 to 250 ng/L showing a correlation of 71% (p=0.0001) with whole blood samples. The results with this POCT method were compared with those obtained using ADVIA Centaur hs-cTnI immunometric method (22). In detail, the Authors tested this method by measuring cTnI values ​​in circulating blood through the skin of the thumb of 4 healthy adults and 5 patients with heart disease (with 52 different measurements overall) (40). The Authors then calculated the correlation between the values ​​of the POCT cTnI method obtained by transdermal route and the ADVIA Centaur hs-cTnI method (r=0.78, p<0.001). According to Fourth Universal Definition of MI (1), the critical threshold of 19 ng/L was calculated by means of a logistic regression comparing the results of the non-invasive transdermal technique and the measurement of the ADVIA Centaur hs-cTnI method (AUC 0.853, sensitivity 100%, specificity 70.59%). Finally, the Authors compared the diagnostic accuracy of the spectrometric POCT and the ADVIA Centaur hs-cTnI method obtaining an AUC of 0.895 (n=52), with a sensitivity of 96% and a specificity of 60% to predict elevated levels of cTnI (i.e., >19 ng/L) (40). Clearly, the results reported by Titus et al. (40) are very preliminary because obtained with a system and instrumentation not yet tested and certified by international bodies and institutions. Nonetheless, these results show what could become possible in the near future (7,8).

CONCLUSIONS
The use of POCT methods for hs-cTn measurement should be considered in many clinical settings, even if hs-cTnI and hs-cTnT measurements with the automated platforms in a clinical laboratory, seem currently still necessary to confirm the results obtained with the hs-cTn POCT methods, at least to rule-in NSTEMI, mainly because of the sub-optimal PPV using the fastest diagnostic algorithms (0/1h) (7,8,10-13). POCT methods demonstrate a positive cost/effectiveness ratio especially when the patient is in rural peripheral areas, in small clinical centres without an equipped clinical laboratory, or when the patient must be transported over long distances (7,8,10-13,42,43).
All the most recent guidelines recommend the use of hs-cTnI POCT methods in particular to rule-out NSTEMI, using the entry sample or the rapid 0/1 h algorithm only. This approach allows to identify low-risk patients, who do not require further invasive tests and can be safely and quickly discharged from the ED (7,8,10-13).
As clearly stated by the international guidelines (11, 12,44), the implementation of hs-cTnI POCT methods requires not only a careful education of the personnel in charge of the biomarker measurement, but also an accurate evaluation of some clinical issues that could arise during routine use of the hs-cTnI POCT methods, especially in the pre-analytical and analytical phases due to possible analytical interferences and clinical difficulties in result interpretation, as well as the need for a validated system in order to guarantee a suitable information system (i.e. connection with the LIS) and the quality control of the procedures and the result reporting.
Another very relevant point is that the Clinical and the Laboratory Medicine Scientific Societies should promote collaborative studies specifically designed for the evaluation of the analytical performance and the cost/benefit ratio of the implementation of the hs-cTn POCT methods in the different countries as well as within the same country. The results of these studies will be able to guide the implementation of the hs-cTn POCT methods into routine clinical practice.

CONFLICT OF INTEREST
None.

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