Potential performance of a 0 h/1 h algorithm and a single cut-off measure of high-sensitivity troponin T in a diverse population: main results of the IN-HOPE study.

AIMS: Chest pain is a major cause of medical evaluation at emergency department (ED) and demands observation to exclude the diagnosis of acute myocardial infarction (AMI). High-sensitivity cardiac troponin assays used as isolated measure and by 0- and 1-h algorithms are accepted as a rule-in/rule-out strategy, but there is a lack of validation in specific populations. METHODS AND RESULTS: The IN-HOspital Program to systematizE Chest Pain Protocol (IN-HOPE study) is a multicentre study that prospectively included patients admitted to the ED due to suspected symptoms of AMI at 16 sites in Brazil. Medical decisions of all patients followed the standard approach of 0 h/3 h protocol, but, in addition, blood samples were also collected at 0 and 1 h and sent to a central laboratory (core lab) to measure high-sensitivity cardiac troponin T (hs-cTnT). To assess the theoretical performance of 0 h/1 h algorithm, troponin < 12 ng/L with a delta < 3 was considered rule-out while a value ≥ 52 or a delta ≥ 5 was considered a rule-in criterion (the remaining were considered as observation group). The main objective of the study was to assess, in a population managed by the 0 h/3 h protocol, the accuracy of 0 h/1 h algorithm overall and in groups with a higher probability of AMI. All patients were followed up for 30 days, and potential events were adjudicated. In addition to the prospective cohort, a retrospective analysis was performed assessing all patients with hs-cTnT measured during the year of 2021 but not included in the prospective cohort, regardless of the indication of the test. A total of 5.497 patients were included (583 in the prospective and 4.914 in the retrospective analysis). The prospective cohort had a mean age of 57.3 (± 14.8) and 45.6% of females with a mean HEART score of 4.0 ± 2.2. By the core lab analysis, 74.4% would be eligible for a rule-out approach (45.3% of them with a HEART score > 3) while 7.3% would fit the rule-in criteria. In this rule-out group, the negative predictive value for index AMI was 100% (99.1-100) overall and regardless of clinical scores. At 30 days, no death or AMI occurred in the rule-out group of both 0/1 and 0/3 h algorithms while 52.4% of the patients in the rule-in group (0 h/1 h) were considered as AMI by adjudication. In the observation group (grey zone) of 0 h/1 h algorithm, GRACE discriminated the risk of these patients better than HEART score. In the retrospective analysis, 1.091 patients had a troponin value of <5 ng/L and there were no cardiovascular deaths at 30 days in this group. Among all 4.914 patients, the 30-day risk of AMI or cardiovascular death increased according to the level of troponin: 0% in the group < 5 ng/L, 0.6% between 5 and 14 ng/L, 2.2% between 14 and 42 ng/L, 6.3% between 42 and 90 ng/L, and 7.7% in the level ≥ 90 ng/L. CONCLUSION: In this large multicentre study, a 0 h/1 h algorithm had the potential to classify as rule-in or rule-out in almost 80% of the patients. The rule-out protocol had high negative predictive value regardless of clinical risk scores. Categories of levels of hs-cTn T also showed good accuracy in discriminating risk of the patients with a very favourable prognosis for cardiovascular death in the group with value < 5 ng/L. CLINICALTRIALS.GOV: NCT04756362.

Avaliação pela tomografia de coerência óptica de stent nacional recoberto com polímero biodegradável eluidor de sirolimus vs. stent eluidor de biolimus A9 em artérias coronárias porcinas / Assessment by optical coherence tomography of a Brazilian biodegradable polymer-coated sirolimus eluting stent vs a biolimus A9-eluting stent in porcine coronary arteries

Introdução: Está em desenvolvimento em nosso meio o stent InspironTM, um stent nacional metálico de cobalto-cromorecoberto com uma mistura de polímeros bioabsorvíveis exclusivamente em sua face abluminal e com liberação de sirolimus. O objetivo deste estudo foi comparar, em um modelo experimental, os achados da tomografia de coerência óptica dos stents InspironTM e BioMatrixTM. Métodos: Os stents foram implantados em artérias coronárias porcinas. Cada indivíduo recebeu os dois tipos de stent, um em cada artéria (artérias descendente anterior e circunflexa), e após 28 dias foi realizado novo estudo angiográfico e empregada a tomografia de coerência óptica para avaliação da hiperplasia neointimal. Resultados: Sete porcos receberam 7 stents InspironTM e 7 stents BioMatrixTM. O diâmetro de referência dos vasos tratados foi de 2,16 + 0,37 mm e a relação balão de implante do stent/artéria foi de 1,17 + 0,16 atm, sem diferença entre os grupos. A perda tardia intrastent foi de 0,53 + 0,56 mm e de 0,32 + 0,37 mm (P = 0,43) para os stents InspironTM e BioMatrixTM, respectivamente. Ocorreu um caso de reestenose angiográfica no grupo stent InspironTM (14% vs. 0; P = 0,2). A tomografia de coerência óptica evidenciou área neointimal intrastent no stent InspironTM de 1,61 + 0,57 mm² e no stent BioMatrixTM de 1,36 + 0,66 mm² (P = 0,47). A área neointimal porcentual foi de 31% no stent InspironTM vs. 23% no stent BioMatrixTM (P = 0,21). Conclusões: Após 28 dias de implante em artérias coronárias porcinas o stent InspironTM apresentou grau de hiperplasia neointimal intrastent semelhante ao do stent BioMatrixTM.

Background: InspironTM, a chrome-cobalt sirolimus-eluting stent covered by a mixture of bioabsorbable polymers on its abluminal side is being developed in Brazil. Our objective was to compare in an experimental study the findings ofoptical coherence tomography for the InspironTM and BioMatrix™ stents. Methods: Stents were implanted in porcine coronary arteries. Each individual received two types of stents, one in each artery (left anterior descending and left circumflex artery). After 28 days, a new angiography was performed and optical coherence tomography was used to assess neointimal hyperplasia. Results: Seven Inspiron™ stents and 7 BioMatrixTM stents were implanted in 7 domestic pigs. The reference diameter of the treated vessels was 2.16 + 0.37 mm and the balloon to artery ratio was 1.17 + 0.16 atm, with no statisticaldifference between groups. In-stent late loss was 0.53 + 0.56 mm and 0.32 + 0.37 mm (P = 0.43) for the InspironTMand BioMatrixTM stents, respectively. There was one case of angiographic restenosis in the InspironTM group (14% vs 0; P = 0.2). Optical coherence tomography showed an instent neointimal area of 1.61 + 0.57 mm² for the InspironTM stent and 1.36 + 0.66 mm² for the BioMatrixTM stent (P = 0.47). The percentage of neointimal area was 31% for the InspironTM stent vs 23% for the BiomatrixTM stent (P = 0.21). Conclusions: Twenty-eight days after implantation in porcine coronaryarteries the InspironTM stent showed a similar degree of neointimal hyperplasia as the BiomatrixTM stent.