Biochemical and Hematological Profile of Covid-19 Patients on Mechanical Ventilation.

Beakground: The prevalence of cardiovascular diseases in COVID-19 patients, such as hypertension, diabetes mellitus, and chronic obstructive pulmonary disease, which are the most common comorbid conditions in COVID-19 patients, is considered a risk factor for premature mortality in the population. The aim of the study is to compare the standard biochemical and hematological markers of COVID-19 patients on mechanical ventilation and those who have recovered, and to identify differences by gender and comorbidities, as well as the dominant marker in comorbidities that frequently shows statistical significance, in order to investigate its prognostic value in further research. METHODS: The study is a retrospective study of patients with RT-PCR confirmed presence of the Sars-CoV-2 virus who were hospitalized at the Zenica Cantonal Hospital. The study lasted from February to April 2021. RESULTS: The results of the study, which included a sample of 302 participants, indicate that men were more represented in both the mechanical ventilation group and the recovered group, with 59.6% compared to women with 40.4%. Among the investigated biochemical and hematological parameters, there was a significantly higher number of leukocytes, urea, creatinine, LDH, and troponin in patients on mechanical ventilation, while the number of platelets was significantly higher in recovered patients. The most common comorbidity was hypertension in both groups of patients, with 24.5%. In patients on mechanical ventilation with cardiovascular disease, there was a significantly higher number of leukocytes, urea, creatinine, LDH, and troponin. In the same patients with three comorbidities, there was a significantly higher number of leukocytes, troponin, and LDH, while recovered patients without comorbidities had a significantly higher number of platelets. CONCLUSIONS: The male gender and comorbidities remain a vicious circle in COVID-19 infection, while biochemical and hematological markers can help in forecasting and improve the clinical treatment of these high-risk patients.

Characteristics of Patients With Acute Coronary Syndrome and Normal Electrocardiogram.

Background: Patients with acute coronary syndrome (ACS) and normal electrocardiogram (ECG) may have an increased risk of late diagnosis and complications of the disease. Objective: To study the demographic, angiographic and echocardiographic characteristics of patients hospitalized for ACS in whom the ECG was normal on admission to the hospital. Methods: This retrospective study included patients who were hospitalized for ACS without ST-elevation between 2015 and 2023 and who had coronary artery disease (CAD) confirmed by coronary angiography. By further inspection of the electronic databases, patients with ACS who had a normal ECG on admission were filtered out and analyzed separately. Results: Of the total 3137 patients with suspected ACS without ST-elevation, 129 patients (4.1%) were diagnosed as having ACS with a normal ECG. In three patients a non-atherosclerotic cause for the ACS was found. A significantly higher proportion of patients had single-vessel (54.3%) compared to two-vessel (29.5%) and three-vessel (14%) CAD. In addition to a normal ECG, 5.7% of patients with single-vessel CAD and 3.5% of patients with multi-vessel CAD had normal troponin levels and normal regional LV systolic function on echocardiography. Conclusion: Less than 5% of hospitalized patients with ACS without ST-elevation had a normal ECG on admission. The majority of these patients have single-vessel CAD. In about 5% of patients with single-vessel CAD, neither elevated troponin levels nor LV asynergy are detected.

Could paramedics use the HEART Pathway to identify patients at low-risk of myocardial infarction in the prehospital setting?

In the Emergency Department, patients with suspected myocardial infarction can be risk stratified using the HEART pathway, which has recently been amended for prehospital use and modified for the incorporation of a high-sensitivity cardiac troponin test. In a prospective analysis, the performance of both HEART pathways in the prehospital setting, with a high-sensitivity cardiac troponin test using 3 different thresholds, was evaluated for major adverse cardiac events at 30 days. We found that both low-risk HEART pathways, when using the most conservative cardiac troponin thresholds, approached but did not reach accepted rule-out performance in the Emergency Department.

Myosin's powerstroke transitions define atomic scale movement of cardiac thin filament tropomyosin.

Dynamic interactions between the myosin motor head on thick filaments and the actin molecular track on thin filaments drive the myosin-crossbridge cycle that powers muscle contraction. The process is initiated by Ca2+ and the opening of troponin-tropomyosin-blocked myosin-binding sites on actin. The ensuing recruitment of myosin heads and their transformation from pre-powerstroke to post-powerstroke conformation on actin produce the force required for contraction. Cryo-EM-based atomic models confirm that during this process, tropomyosin occupies three different average positions on actin. Tropomyosin pivoting on actin away from a TnI-imposed myosin-blocking position accounts for part of the Ca2+ activation observed. However, the structure of tropomyosin on thin filaments that follows pre-powerstroke myosin binding and its translocation during myosin's pre-powerstroke to post-powerstroke transition remains unresolved. Here, we approach this transition computationally in silico. We used the myosin helix-loop-helix motif as an anchor to dock models of pre-powerstroke cardiac myosin to the cleft between neighboring actin subunits along cardiac thin filaments. We then performed targeted molecular dynamics simulations of the transition between pre- and post-powerstroke conformations on actin in the presence of cardiac troponin-tropomyosin. These simulations show Arg 369 and Glu 370 on the tip of myosin Loop-4 encountering identically charged residues on tropomyosin. The charge repulsion between residues causes tropomyosin translocation across actin, thus accounting for the final regulatory step in the activation of the thin filament, and, in turn, facilitating myosin movement along the filament. We suggest that during muscle activity, myosin-induced tropomyosin movement is likely to result in unencumbered myosin head interactions on actin at low-energy cost.

Comparison of Del Nido (a different application) and crystalloid blood cardioplegia on arrhythmia and early results.

BACKGROUND: The results of the use of del-Nido(DN) solution using a different method or crystalloid blood cardioplegia in coronary bypass patients were compared. We aimed to investigate the effects on intraoperative and postoperative arrhythmias, arrhythmia durations and early results. METHODS: The study included 175 patients using crystalloid blood cardioplegia (Group 1) and 150 patients using DN solution(Group 2). In the DN group, 75% of the calculated plegia dose was given first. the remaining part was applied by giving from grafts. Intraoperative/postoperative data were compared. RESULTS: There was no significant difference between the groups in terms of demographic characteristics. Preop troponin level was similar.(p = 0.190) However, there was a statistical difference between the postoperative 6th hour.(p = 0.001) There was no difference in troponin values at the postoperative 24th hour. (p = 0.631) Spontaneous rhythm occurred at the cardiopulmonary by pass (CPB) weaning stage in most of the patients in Group 2 (95.3%). Although the need for temporary pacing was less in Group 2, it was not significant.(p = 0.282) No patient required permanent pacing. CPB duration, cross clamp times and intraoperative glucose levels, intensive care follow-up times and hospitalization times were found to be shorter in Group 2. Although the postoperative atrial fibrillation frequency was similar (p = 0.261), the time to return to sinus was lower in Group 2.(p = 0.001). CONCLUSION: The use of DN cardioplegia solution provides significant positive contributions to avoid arrhythmias compared to crystalloid blood cardioplegia. DN solution applied with this method may contribute to reducing the anxieties associated with its use in isolated coronary artery bypass surgery.

Ablação septal por radiofrequência na cardiomiopatia hipertrófica obstrutiva: a troponina é bom marcador de sucesso terapêutico? / Radiofrequency septal ablation in obstructive hypertrophic cardiomyopathy: is troponin a good marker of therapeutic success?

INTRODUÇÃO: A terapia de redução septal na Cardiomiopatia Hipertrófica Obstrutiva (CMHO) é indicada quando há sintomas refratários à terapêutica otimizada. Dentre estas terapias, recentemente foi proposta a ablação septal por radiofrequência (RF) com cateteres utilizados na eletrofisiologia para ablação de arritmias atriais e ventriculares. A ablação por RF é realizada com auxílio de ecocardiograma transesofágico com melhor controle da área abordada e redução do risco de lesões ao sistema de condução. Este trabalho tem como intuito apresentar uma série de casos de pacientes com CMHO que foram abordados por meio de ablação septal por RF, avaliando-se se a elevação dos níveis séricos de troponina, se correlacionam com a redução do gradiente intraoperatório e sucesso terapêutico. MÉTODOS: Estudo observacional, do tipo coorte histórica por análise de prontuário. As variáveis foram descritas por estatísticas de posição e escala para variáveis contínuas e frequências absolutas e relativas para variáveis categóricas (ou categorizadas). As análises foram realizadas com auxílio do software R (R Core Team, 2022). E os testes de hipótese utilizarão nível de significância de 5%. RESULTADOS: Analisaram-se 36 pacientes, sendo 18 (50%) do sexo masculinos. A troponina foi dosada no pré-operatório e no pós-operatório imediato, porém foi realizada usando tipos diferentes entre os pacientes, seguindo descrita como número de vezes acima do valor de referência. Observou-se uma elevação acima dos valores de referência em 83,3% dos pacientes analisados, e antes do procedimento, dois pacientes já apresentavam troponina acima do valor de referência, e se mantiveram acima após. Também se observou uma redução do GVSVE no intraoperatório de 38.3mmHg [30.7 a 45.8] com p<0,01. O gráfico 1 apresenta a relação do logaritmo do número de vezes da troponina acima do valor de referência contra o gradiente máximo pós-procedimento e das respectivas diferenças em relação ao valor de base (pré-procedimento). A correlação de Spearman foi respectivamente 0,47 (p = 0,065), não evidenciando uma correlação entre os achados. Gráfico 1. Dispersão do logaritmo diferença do número de vezes da troponina acima do valor de referência contra a redução gradiente máximo pós-procedimento. CONCLUSÃO: Apesar dos valores de troponina estarem maiores pós procedimento, concluímos que a troponina não deve ser usada como marcador de sucesso terapêutico.

Differentiating electrocardiographic indications of massive and submassive pulmonary embolism: A cross-sectional study in Southern Iran from 2015 to 2020.

BACKGROUND: Although using electrocardiogram (ECG) for pulmonary embolism (PE) risk stratification has shown mixed results, it is currently used as supplementary evidence in risk stratification. This cross-sectional study aimed to assess and compare ECG findings of massive and submassive PE versus segmental PE. METHODS: This cross-sectional study included 250 hospitalized patients with a confirmed diagnosis of acute PE from 2015 to 2020 in Southern Iran. Demographic variables, clinical data, troponin levels, on-admission ECG findings, echocardiography findings, and ECG findings 24 h after receiving anticoagulants or thrombolytics were extracted. RESULTS: Patients diagnosed with submassive or massive PE exhibited significantly higher rates of right axis deviation (p = .010), abnormal ST segment (p < .0001), S1Q3T3 pattern (p < .0001), inverted T wave in leads V1-V3 (p < .0001), inverted T wave in leads V4-V6 (p < .0001), and inverted T wave in leads V1-V6 (p < .0001). In a multivariable model, inverted T wave in leads V1-V3, inverted T wave in leads V4-V6, pulse rate, and positive troponin test were the statistically independent variables for predicting submassive or massive PE. Furthermore, inverted T wave in leads V1-V3 (sensitivity: 85%, specificity: 95%, accuracy: 93%, AUC: 0.902) and troponin levels (sensitivity: 72%, specificity: 86%, accuracy: 83%, AUC: 0.792) demonstrated the best diagnostic test performance for discriminating submassive or massive PE from segmental PE. CONCLUSION: In addition to clinical rules, ECG can serve as an ancillary tool for assessing more invasive testing and earlier aggressive treatments among patients with PE, as it can provide valuable information for the diagnosis and risk stratification of submassive or massive PE.

Clinical Value of Troponin Levels to Cardiac Function and Prognosis in Patients with Fulminant Myocarditis.

Troponin (Tn) is a biomarker related to myocardial necrosis and is elevated in patients with myocarditis. This study aimed to investigate the association between cardiac Tn levels and the course of cardiac function, and prognosis in patients with fulminant myocarditis (FM) receiving percutaneous mechanical circulatory support (MCS).We used data from a multicenter retrospective registry, CHANGE PUMP 2, which included 216 patients with FM who required MCS. Among them, 141 patients whose Tn levels were available were analyzed. The patients were divided into low and high Tn groups according to the median values of TnT and TnI.The median age was 54 years, and 59.6% were male. The TnT and TnI on day 1 (at MCS initiation) were 3.8 (1.4-10.0) and 21.4 (8.4-68.8) ng/mL. While the left ventricular ejection fraction (LVEF) was similar on day 1 (25.0% versus 24.5%), the low Tn group showed better LVEF improvement on day 7 than the high Tn group (45.0% versus 25.3%, P < 0.001). LVEF at 1 year after admission was higher in the low Tn group (65.0% versus 59.7%, P = 0.039). The low Tn group had a better 90-day composite endpoint in death, durable left ventricular assist device implantation, and heart transplantation compared to the high Tn group (hazard ratio 0.47, 95% CI 0.23-0.95).Tn levels were associated with short- and long-term cardiac recovery and adverse outcomes in patients with FM receiving MCS due to cardiogenic shock.

The CRP troponin test (CTT) stratifies mortality risk in patients with non-ST elevation myocardial infarction (NSTEMI).

INTRODUCTION: The C-reactive protein (CRP)-troponin-test (CTT) comprises simultaneous serial measurements of CRP and cardiac troponin and might reflect the systemic inflammatory response in patients with acute coronary syndrome. We sought to test its ability to stratify the short- and long-term mortality risk in patients with non-ST elevation myocardial infarction (NSTEMI). METHODS: We examined 1,675 patients diagnosed with NSTEMI on discharge who had at least two successive measurements of combined CRP and cardiac troponin within 48 h of admission. A tree classifier model determined which measurements and cutoffs could be used to best predict mortality during a median follow-up of 3 years [IQR 1.8-4.3]. RESULTS: Patients with high CRP levels ( > 90th percentile, >54 mg/L) had a higher 30-day mortality rate regardless of their troponin test findings (16.7% vs. 2.9%, p < 0.01). However, among patients with "normal" CRP levels ( < 54 mg/L), those who had high troponin levels ( > 80th percentile, 4,918 ng/L) had a higher 30-day mortality rate than patients with normal CRP and troponin concentrations (7% vs. 2%, p < 0.01). The CTT test result was an independent predictor for overall mortality even after adjusting for age, sex, and comorbidities (HR = 2.28 [95% CI 1.56-3.37], p < 0.01 for patients with high troponin and high CRP levels). CONCLUSIONS: Early serial CTT results may stratify mortality risk in patients with NSTEMI, especially those with "normal" CRP levels. The CTT could potentially assess the impact of inflammation during myocardial necrosis on the outcomes of patients with NSTEMI and identify patients who could benefit from novel anti-inflammatory therapies.

Intensive Blood Pressure Lowering in Individuals With Low Diastolic Blood Pressure and Elevated Troponin Levels in SPRINT.

BACKGROUND: Among individuals with hypertension and low diastolic blood pressure (DBP), the optimal BP target remains controversial due to concerns that BP lowering may reduce coronary perfusion. We determined the impact of intensive BP control among individuals with elevated systolic BP who have low DBP and elevated hs-cTnT (high-sensitivity cardiac troponin T) levels. METHODS AND RESULTS: A total of 8828 participants in SPRINT (Systolic Blood Pressure Intervention Trial) were stratified by baseline DBP. Those with low DBP (<70 mm Hg) were further stratified by elevated hs-cTnT (≥14 ng/L) at baseline. The effects of intensive versus standard BP lowering on a cardiovascular disease composite end point, all-cause death, and 1-year change in hs-cTnT were determined. The combination of low DBP/high hs-cTnT was independently associated with a higher risk for cardiovascular disease and all-cause death, as well as greater 1-year increases in hs-cTnT, compared with DBP ≥70 mm Hg. However, randomization to intensive versus standard BP lowering led to similar reductions in cardiovascular disease risk among individuals with low DBP/high hs-cTnT (hazard ratio [HR], 0.82 [95% CI, 0.57-1.19]), low DBP/low hs-cTnT (HR, 0.48 [95% CI, 0.29-0.79]), and DBP ≥70 mm Hg (HR, 0.73 [95% CI, 0.60-0.89]; P for interaction=0.20). Intensive BP lowering also led to a reduction in all-cause death that was similar across groups (P for interaction=0.57). CONCLUSIONS: In this nonprespecified subgroup analysis of SPRINT, individuals with low DBP and elevated hs-cTnT, low DBP and nonelevated hs-cTnT, and DBP ≥70 mm Hg derived similar cardiovascular disease and mortality benefits from intensive BP lowering. These findings warrant confirmation in other studies.

Comparison of troponin and natriuretic peptides in Takotsubo syndrome and acute coronary syndrome: a meta-analysis.

OBJECTIVE: Takotsubo syndrome (TTS) is an acute heart failure syndrome which resembles acute coronary syndrome (ACS) at presentation. Differentiation requires coronary angiography, but where this does not occur immediately, cardiac biomarkers may provide additional utility. We performed a meta-analysis to compare troponin and natriuretic peptides (NPs) in TTS and ACS to determine if differences in biomarker profile can aid diagnosis. METHODS: We searched five literature databases for studies reporting NPs (Brain NP (BNP)/NT-pro-BNP) or troponin I/T in TTS and ACS, identifying 28 studies for troponin/NPs (5618 and 1145 patients, respectively). RESULTS: Troponin was significantly lower in TTS than ACS (standardised mean difference (SMD) -0.86; 95% CI, -1.08 to -0.64; p<0.00001), with an absolute difference of 75 times the upper limit of normal (×ULN) higher in ACS than TTS. Conversely, NPs were significantly higher in TTS (SMD 0.62; 95% CI, 0.44 to 0.80; p<0.00001) and 5.8×ULN greater absolutely. Area under the curve (AUC) for troponin in ACS versus TTS was 0.82 (95% CI, 0.70 to 0.93), and 0.92 (95% CI, 0.80 to 1.00) for ST-segment elevation myocardial infarction versus TTS. For NPs, AUC was 0.69 (95% CI, 0.48 to 0.89). Combination of troponin and NPs with logistic regression did not improve AUC. Recursive Partitioning and Regression Tree analysis calculated a troponin threshold ≥26×ULN that identified 95% cases as ACS where and specificity for ACS were 85.71% and 53.57%, respectively, with 94.32% positive predictive value and 29.40% negative predictive value. CONCLUSIONS: Troponin is lower and NPs higher in TTS versus ACS. Troponin had greater power than NPs at discriminating TTS and ACS, and with troponin ≥26×ULN patients are far more likely to have ACS.

Prognostic value of perioperative high sensitivity troponin in patients undergoing hip and knee arthroplasty.

The authors conducted a prospective observational study to investigate the prognostic value of high-sensitivity Troponin I (hs-TnI) in the short- and long-term periods after orthopedic surgery, including Total Hip and Knee Arthroplasty (THA and TKA, respectively), in a tertiary orthopedic center in Brazil. Perioperative Myocardial Injury (PMI) was defined as an absolute increase in hs-TnI of ≥ 26 ng/L above preoperative values. The primary endpoint was all-cause mortality assessed at 30 days and 18 months after surgery. The secondary endpoint consisted of a composite outcome: cardiovascular death, acute myocardial infarction, angina requiring revascularization, and/or stroke. The authors compared Relative Risks (RR) of all-cause mortality and composite outcomes in patients with or without PMI at 30 days and 18 months. A Cox proportional hazards model for long-term outcomes was calculated and adjusted for age > 70 years, gender, and Revised Cardiac Risk Index (RCRI) class ≥ 2. PMI occurred in 3.4 % of all surgeries. At 30-days, 6.6 % of patients with PMI had died versus none without PMI. At 18 months, 20.0 % of PMI versus 4.7 % without PMI had died (RR = 5.0; 95 % Confidence Interval [95 % CI 1.3-19.3]). Based on composite outcomes in short and long-term periods, the RRs were 16.2 (95 % CI 2.7-96.5) and 7.7 (95 % CI 2.2-26.6), respectively. PMI was associated with all-cause mortality after 18 months and increased risk for a composite outcome (Hazard Ratio [HR = 3.97], 95 % CI 1.13-13.89 and HR = 5.80, 95 % CI 1.93-17.45, respectively). Patients with PMI who underwent THA or TKA presented worse short- and long-term prognoses compared to those without PMI.

Imprecision of high-sensitivity cardiac troponin assays at the female 99th-percentile.

BACKGROUND: An analytical benchmark for high-sensitivity cardiac troponin (hs-cTn) assays is to achieve a coefficient of variation (CV) of ≤ 10.0 % at the 99th percentile upper reference limit (URL) used for the diagnosis of myocardial infarction. Few prospective multicenter studies have evaluated assay imprecision and none have determined precision at the female URL which is lower than the male URL for all cardiac troponin assays. METHODS: Human serum and plasma matrix samples were constructed to yield hs-cTn concentrations near the female URLs for the Abbott, Beckman, Roche, and Siemens hs-cTn assays. These materials were sent (on dry ice) to 35 Canadian hospital laboratories (n = 64 instruments evaluated) participating in a larger clinical trial, with instructions for storage, handling, and monthly testing over one year. The mean concentration, standard deviation, and CV for each instrument type and an overall pooled CV for each manufacturer were calculated. RESULTS: The CVs for all individual instruments and overall were ≤ 10.0 % for two manufacturers (Abbott CVpooled = 6.3 % and Beckman CVpooled = 7.0 %). One of four Siemens Atellica instruments yielded a CV > 10.0 % (CVpooled = 7.7 %), whereas 15 of 41 Roche instruments yielded CVs > 10.0 % at the female URL of 9 ng/L used worldwide (6 cobas e411, 1 cobas e601, 4 cobas e602, and 4 cobas e801) (CVpooled = 11.7 %). Four Roche instruments also yielded CVs > 10.0 % near the female URL of 14 ng/L used in the United States (CVpooled = 8.5 %). CONCLUSIONS: The number of instruments achieving a CV ≤ 10.0 % at the female 99th-percentile URL varies by manufacturer and by instrument. Monitoring assay precision at the female URL is necessary for some assays to ensure optimal use of this threshold in clinical practice.

The significance of B-type natriuretic peptide in predicting early mortality among pulmonary embolism patients, alongside troponin: insights from a multicentric registry.

BACKGROUND: Early mortality assessment in acute pulmonary embolism (PE) is crucial for treatment decisions. The role of natriuretic peptides in this context is debated. This study explores elevated B-type natriuretic peptide (BNP) levels, relative to the upper normal limit (UNL), predicting mortality in PE, comparing with troponin (Tn). METHODOLOGY: A multicenter PE registry analyzed predictive values for early mortality risk using BNP and Tn, based on proportional elevation to the UNL. Patients followed current PE guidelines. RESULTS: Among 1677 PE patients, BNP's AUC exceeded Tn for all-cause (0.727 vs. 0.614) and PE-related mortality (0.785 vs. 0.644), though nonsignificant. BNP's cutoff was 3.5 times UNL for both all-cause and PE-related mortalities; Tn cutoffs were 1.38 and 1.23 times UNL, respectively. CONCLUSION: Elevated BNP relative to UNL significantly predicts all-cause and PE-related mortality. While akin to Tn, BNP merits consideration in assessing acute PE risk, especially in intermediate-high-risk cases.

Could Computed Tomography Coronary Angiography Replace Invasive Coronary Angiography as a First-Line Diagnostic Investigation in Suspected Acute Coronary Syndromes? A Decision-Analytic Model.

BACKGROUND: The implementation of high-sensitivity cardiac troponin (hs-cTn) assays into clinical practice has resulted in the identification of a novel cohort of patients with modestly increased troponin concentrations. Subsequent increases in rates of coronary angiography have been observed, without significant increases in rates of coronary revascularisation. Computed tomography coronary angiography (CTCA) is a non-invasive investigation that offers the opportunity to decouple investigation from the impetus to revascularise, and may provide an alternative, more risk-appropriate initial investigative strategy for the cohort with low to moderate hs-cTn increases. This analysis seeks to define the threshold of pre-test probability of coronary revascularisation in patients with suspected acute coronary syndrome at which a strategy of initial CTCA is safe and a more cost-effective approach than standard invasive coronary angiography (ICA). METHODS: A cost-benefit evaluation was conducted using a decision-analytic model. The primary outcome measure was the incremental cost-effectiveness ratio (ICER) of CTCA in comparison with ICA as an initial diagnostic investigation for patients with hs-cTnT levels between 5 and 100 ng/L. Secondary outcome measures of costs, patient outcomes, and quality-adjusted life years were analysed. RESULTS: Median base case ICER over 1,000 trials was $17,163 AUD but demonstrated large variability. Sensitivity analysis demonstrated that CTCA was cost-effective until the probability of requiring revascularisation was ∼60%, beyond which point CTCA was associated with higher costs and poorer outcomes than ICA. CONCLUSIONS: Computed tomography coronary angiography may be a cost-effective first-line investigation for patients with moderate hs-cTnT rises until/up to a 60% pre-test probability for receiving coronary revascularisation. To objectively assess the optimal circumstances of cost-effectiveness, prospective evaluation incorporating the estimated probability of revascularisation will be required.