Elevated Troponin Research Articles

Mortality prediction using high-sensitivity troponin after coronary artery bypass surgery

Abstract Introduction Recommendations regarding the threshold levels of cardiac troponin elevations for the definition of peri-operative myocardial infarction and clinically important peri-procedural myocardial injury in patients undergoing cardiac surgery range widely (>10 to ≥70x the upper limit of normal (ULN)) (1,2). Limited evidence is available to support these recommendations. In a recent multicentre cohort study, Devereaux and colleagues (3) characterised appropriate thresholds of high-sensitivity troponin-I (hs-TnI) for defining myocardial injury within 3 days after cardiac surgery. The threshold associated with an increased risk of 30-day mortality after coronary artery bypass grafting (CABG) was 218 xULN (95% confidence interval (CI), 40-318) of the hs-TnI assay. There have been no large studies assessing this threshold using high-sensitivity troponin-T (hs-TnT). Furthermore, the long-term prognostic value of troponin following CABG is unknown. Purpose The aim of our study was to assess the threshold associated with an increased risk of 30-day and 5-year mortality using hs-TnI assays, and to compare these thresholds to those using hs-TnT assays. Methods A retrospective cohort study was carried out using the National Institute for Health Research Health Informatics Collaborative Cardiovascular dataset (4,5) of all consecutive patients who had a troponin measured at five hospitals between 2010 and 2017. Patients who had a troponin measurement within three days following CABG were identified. Results were analysed using multivariable adjusted restricted cubic spline Cox regression. All hazard ratios were adjusted for the following components of the European System for Cardiac Operative Risk Evaluation II (EuroSCORE II); age, gender, renal impairment, poor mobility, chronic lung disease, diabetes, left ventricular function, and pulmonary hypertension. Analyses on troponin were performed using the peak troponin level, which was the highest troponin level measured within the first three days following CABG. All troponin measurements were high-sensitivity and were standardised by using the ratio of the observed troponin value divided by the ULN for each troponin assay. The reference for hazard ratios was a troponin level of 1 xULN. Results A total of 1055 patients (median age 72 years (interquartile range 63 to 78), 79% male) had a troponin measured within three days post-CABG at the five centres between 2010 and 2017. The threshold for hs-TnI associated with an increased mortality risk was 196xULN (95%CI, 42-494) for predicting 30-day mortality (Figure 1A) and 157xULN (95%CI, 32-409) for 5-year mortality (Figure 1B). The thresholds were similar for hs-TnT assays (Figure 1C and 1D). Conclusion The currently recommended troponin thresholds for diagnosing significant myocardial injury following cardiac surgery (>10 to ≥70xULN) are too low. There was good correlation between hs-TnI and hs-TnT measurements for predicting both short- and long-term mortality.Figure 1

The specificity of cardiac troponin elevations for myocardial infarction declines with age

Abstract Background Cardiac troponin T (cTnT) and I (cTnI) are the gold standard biomarkers of myocardial infarction (MI). Studies have shown that the concentration of cTn increases with age among healthy individuals, but the clinical impact of this is unclear. Further, there seem to be a difference in the increases in cTnI and in cTnT - the latter being more sensitive to increasing age. Purpose To investigate the impact of age on the diagnostic ability of cTnT and cTnI for myocardial infarction. Methods This nationwide cohort study includes patients admitted with cTn measurements from 2009-2022 using one of five cTn assays: Roche high-sensitivity cTnT (hs-cTnT), Abbott Alinity high sensitivity cTnI (hs-cTnI), Siemens Vista Hs-cTnI, Siemens Atellica hs-cTnI and Beckman-Coulter hs-cTnI. We selected the peak concentration of cTn on admission and grouped patients into those who had cTnI and those who had cTnT measured which were divided into age groups of <40 years, 40-50 years, 50-60 years, 60-70 years, 70-80 years, 80-90 years and >90 years. The primary outcome was a diagnosis of MI during admission. Receiver operating characteristics (ROC) were used for the concentration of cTn normalized to the assays 99th percentile, and we explored the specificity of elevations of each assay above the 99th percentile. Results A total of 350,428 patients were included in this study with a median age of 67 years (IQR 52-77); 188,382 (54%) were males and 48,262 (14%) had a history of ischemic heart disease prior to the admission. When grouping for type of cTn used, more patients were treated when hs-cTnT (240,660, 69%) was used compared with hs-cTnI (109,768, 31%). The patient treated using hs-cTnT were slightly older than patients treated with hs-cTnI, 67 years (IQR 53-77) vs 65 years (53-77) p<0.001. During the admission 29,023 patients (8.3%) had a MI. Figure 1 panel A shows the ROC curve of hs-cTnT and hs-cTnI for each age group. Both biomarkers showed a decline in the area under the curve (AUC) with increasing age. Figure 1 panel B shows the AUC for each age group. Hs-cTnI had a higher AUC for all age groups and seemed to decrease less with age. Figure 2 shows the specificity for the 99th percentile of each assay for the age groups. There were substantial differences in the specificity at the 99th percentile between cTn assays, with the cTnT assay being the least specific for all age groups, while the two Siemens assays had the highest specificity. An elevation above the 99th percentile of the cTnT assay had a specificity of 3% in the group of patients >90 years old. Conclusion The specificity of elevation of cTn for MI declined with increasing age for all assays. This decline seemed to be largest for the cTnT assay were an elevation above the 99th percentile among patients >90 years old had a specificity of 3% for MI.Figure 1Figure 2

Myocardial injury after transcatheter aortic valve replacement according to VARC-3 criteria

Abstract Background Periprocedural myocardial injury (PPMI) is frequent in patients undergoing transcatheter aortic valve replacement (TAVR). PPMI after TAVR as defined by Valve Academic Research Consortium-2 (VARC-2) criteria occurs in >50% of the patients and had inconsistent results regarding prognostic significance. However, recent VARC-3 definition is more specific, having increased the troponin threshold from 15-times to 70-times the upper reference limit (URL) to define PPMI. This recent definition of PPMI following TAVR lacks the clinical validation. Objective To determine the incidence, predictors and clinical impact of PPMI following TAVR as defined by recent VARC-3 criteria. Methods We included 1,394 consecutive patients who underwent TAVR with a new generation transcatheter heart valve in two tertiary centers in Canada and Italy, from 2015 to 2022. Patients undergoing a trans-aortic or a trans-apical approach were excluded. High-sensitivity troponin levels were assessed at baseline and within 24 hours after the procedure. PPMI was defined according to VARC-3 criteria as an increase ≥70 times in troponin levels (vs. ≥15 times according to VARC-2 definition). Baseline, procedural and follow-up data were prospectively collected in a dedicated database. Results PPMI was diagnosed in 193 patients (14%) according to the VARC-3 criteria. Female sex and peripheral artery disease were found independent predictors of PPMI in the multivariable analysis (p<0.01 for both). PPMI was associated with a higher risk of mortality at 30-day (HR: 2.76, 95% CI: 1.54-4.95, p=0.001 for all-cause mortality; HR: 9.54, 95%CI: 2.69 to 33.80, p<0.001 for cardiovascular mortality) and 1-year-follow-up (HR: 1.52, 95%CI: 1.02-2.27, p=0.037 for all-cause mortality; HR: 3.04, 95%CI: 1.68-5.50, p<0.001 for cardiovascular mortality). PPMI according to VARC-2 criteria had no impact on mortality (Figure 1). According to restricted cubic splines analysis, the minimal threshold at which high-sensitivity troponin elevation is significantly associated with 1-year all-cause mortality is an 82-fold increase above URL (Figure 2). Conclusions About 1 out of 10 patients undergoing TAVR in the contemporary era had PPMI as defined by recent VARC-3 criteria and it had a negative impact on early and late survival. Baseline factors as female gender and peripheral disease increased the risk. Further studies on the prevention of PPMI post-TAVR and implementing measures to improve outcomes in PPMI patients are warranted.Kaplan-Meier estimates of mortalityRestricted cubic splines analysis

Spontaneous Aortic Rupture: A Case Report.

Acute aortic syndrome (AAS) includes the disease processes of aortic dissection, penetrating atherosclerotic ulcer, and intramural hematoma. This case demonstrates an atypical presentation of the disease and offers approaches to potentially prevent missed diagnoses. An 87-year-old female with hypertension and Alzheimer's dementia presented to the emergency department with stable vital signs and a chief complaint of throat pain. Initial work-up was significant for ischemia on electrocardiogram and elevated troponin. Computed tomography of the soft tissue neck revealed evidence of a ruptured aorta. Aortic rupture is a fatal complication of AAS. In an elderly patient with a history of hypertension, ischemic changes on electrocardiogram, and nonspecific pain, AAS should be on the emergency physician's differential even in the setting of a benign or limited history and exam.

Relationship of troponins with in-hospital mortality in adults with covid-19 in a colombian caribbean city: a nested case-control study

Background: myocardial injury, characterized by elevated cardiac troponin levels, is a common finding in severe COVID-19 cases, occurring in up to 38% of patients. It has been identified as an independent predictor of mortality. Objective: our aim is to assess the predictive value of cardiac troponin levels for in-hospital mortality among adults hospitalized with COVID-19 in Barranquilla, Colombia, during the period from January to June 2021. Methods: this study is a nested case-control analysis within a retrospective cohort. It encompasses individuals aged 18 and older with a confirmed diagnosis of COVID-19 who were hospitalized between January and June 2021 (n = 358). We describe the demographic and paraclinical characteristics of the patients and their association with outcomes at the time of discharge. We also estimate the diagnostic accuracy, including sensitivity, specificity, and predictive values, of elevated troponin levels in predicting in-hospital mortality. Results: patients with elevated troponin levels demonstrated a significantly increased risk of in-hospital mortality (OR: 9.4; 95% CI: 5.5-16.0; p < 0.05) and had a notably higher in-hospital mortality rate (55.6%) compared to those with non-elevated troponin levels (11.7%). The troponin biomarker exhibited a sensitivity of 77.9% and specificity of 72.7%, with positive and negative predictive values of 55.6% and 88.3%, respectively, for in-hospital mortality. Conclusion: troponin elevation in subjects with COVID-19 is positively related to in-hospital mortality, independently of other conditions such as age group, comorbidities, or oxygen therapy requirement.

Abstract 12000: Prolonged Arterial Phase is Caused of the Chest Pain in Takotsubo Cardiomyopathy A Dynamics Angiography and Artificial Intelligence Analysis

Introduction: Takotsubo Cardiomyopathy (TCM) known as “Broken Heart Syndrome” is triggered by extreme emotional or physical stress. The typical TCM patient features chest pain, ST elevation, elevated troponin, reduced ejection fraction (EF), patent coronary artery, and apical ballooning. Hypothesis: Could abnormal coronary flow explain chest pain in Takotsubo patients? Methods: The patient with severe chest pain, elevated troponin, ST change, patent coronary arteries, and apical ballooning underwent angiography and review with a new dynamic recording technique. Ten patients without ACS, normal EF, and no coronary artery disease served as control. At first, the angiographic recording started when the contrast was injected into the coronary artery. Then the recording continued with the blood in white color moving in until all contrast disappeared from the arteries. The angiogram was recorded at 15 images per second. The review of coronary images focused on the blood flow in white on top of a background of black contrast. The arterial phase (AP) calculation began when the blood moved in and ended when all the contrast was flushed out of the distal arterial vasculature. The two-layer artificial intelligence program was built based on U-net and Densenet-121. The first layer, with a segmentation model and Convolutional neural network is responsible for detecting the starting frame of AP with a full index of contrast. The second layer with a segmentation model will detect the ending frame of AP. All TCM patient was followed up in one year. Results: Fifteen TCM patients met the criteria (12/15 female). The AP in the TCM group was 3.17 +/- 0.53 seconds compared with 1.62 +/- 0.26 seconds in the control group (P<0.001). The TCM group had a mean EF 33.9 +/- 7.6 %, and all recovered to 58.8 +/- 12.6 % after two weeks. At one year follow-up, all patients had no chest pain and no re-admission, except for one case of non-cardiovascular mortality associated with septic shock from pneumonia 3 months after the index event. Conclusions: Chest pain in TCM was caused by slow flow (measured as prolonged arterial phase) which was detrimental to myocardial contraction. Their prognosis was benign because all patients recovered.

Abstract 16450: Increased Monocyte Count and Neutrophil-to-Lymphocyte Ratio With ICI Myocarditis

Introduction: Diagnosing immune checkpoint inhibitor (ICI) myocarditis remains complex in practice, often requiring advanced imaging or invasive endomyocardial biopsy. We constructed an institutional cohort of patients who received at least 1 dose of ICI and developed probable or definite ICI myocarditis. Hypothesis: We hypothesized that routine serum biomarkers, including troponin I, neutrophil-to-lymphocyte ratio (NLR), monocytes, and AST/ALT, would be elevated and peak at diagnosis. Methods: This retrospective cohort study used EHR data from patients on ICI at a single academic institution who developed probable or definite myocarditis from 7/2015 - 1/2023. Inclusion criteria and diagnosis date were defined using Bonaca criteria and/or documented clinical consensus, e.g. initiation of steroids for presumed myocarditis. Primary outcomes were levels of troponin I/high sensitivity troponin I, monocytes, NLR, and AST/ALT. LOESS regression with default smoothing parameter α = 0.75 was used to evaluate biomarker patterns 7 days pre- and post- diagnosis. Results: We included 16 cases of myocarditis. At diagnosis, most patients had at least 1 significant elevation in troponin I (100%), AST (81%), ALT (63%), or monocytes (69%) while on ICI (Figure 1). After diagnosis, absolute monocyte and lymphocyte count initially decreased before rebounding. Serum NLR rose prior to and briefly after diagnosis (Figure 2). Conclusions: Peripheral cardiac and non-cardiac biomarkers change with ICI myocarditis. Further research on routine non-cardiac biomarkers associated with myocarditis and other ICI toxicities may help prevent high-grade adverse events.

Abstract 202: Liposome-Encapsulated Hemoglobin (HbV) Rescues Hemorrhagic Shock Heart Through Anti-Ischemic and Anti-Arrhythmogenic Effects on Myocardium in Repetitive 65% Bleeding Rat Model

Phase I clinical trial of Liposome-encapsulated hemoglobin vesicles (HbVs) was successfully accomplished. Since several ameliorating mechanisms are not fully understood on HbVs, to investigate its mechanisms of salutary effect on myocardium, optical mapping analysis (OMP) and electrophysiological study (EPS), immunostaining pathological examination for HIF1-alpha in heart and measurement of blood troponin I (TnI) were performed in 30% spontaneous arterial bleedings five times up to approximately total 65% hemorrhage in rats. Eighteen rats in each group were resuscitated by immediately after bleeding by same volume as bleedings each five times by transvenous infusion of 5%albumin solution (ALB-group), washed erythrocytes (wRBC-group) and HbVs (HbV-group). Survival effects over 24 hours were examined. After excising heart, OMP and EPS were performed. All rats died in ALB-group, whereas all survived in wRBC-group and HbV-group. OMP showed impaired (prolonged) action potential duration dispersion (APDd: which is arrhythmogenic index) in LV in ALB-group, whereas APDds were attenuated in HbV-group and wRBC-group (26±4 vs. 11±6, 14±5ms, P<0.05). Lethal arrhythmias (ventricular tachycardia [VT]/ventricular fibrillation [VF]; VT/VF) were provoked by EPS and/or spontaneously occurred in ALB-group whereas not in both wRBC-group and HbV-group. HIF1-alpha was positively stained and TnI levels were significantly elevated only in ALB-group (Peak TnI; 186±47 vs. 64±25, 91±24, 44±10pg/mL, P<0.05: Figure). Conclusions: HbVs rescue lethal hemorrhage through improving lethal arrhythmias and myocardial damages by reflected by inducing HIF1-alpha and elevated TnI. HbVs could be useful for resuscitation and saving life from gun-shot arterial bleeding on-site occurred in terrorisms.

Abstract 19078: Coronary Artery Disease in Very Young Adults: Characteristics, Associated Factors and In-Hospital Mortality

Introduction: Premature CAD carries a poor long-term prognosis. However, there is little data on CAD in very young adults. Understanding the characteristics and associated factors in this population is paramount to the prevention and improvement of outcomes of CAD. Aims To assess characteristics, associated factors, and in-hospital mortality in adults aged 18-35 years with significant CAD (S-CAD) undergoing invasive coronary angiography. Methods: This is a retrospective cohort study of patients who underwent coronary angiography in a single academic center from 2003-2023. S-CAD was defined as major epicardial CAD with at least 50% stenosis. Chi-square, Fischer exact, and Mann Whitney U tests were used to analyze categorical and continuous variables respectively. Logistic regression was used for multivariable analysis. Results: A total of 330 patients were included in the study. Patient characteristics are presented in table 1. Factors associated with the incidence of S-CAD include ST elevation, elevated troponin, total cholesterol, LDL, triglyceride, glucose, high WBC & platelet count, low Platelet: WBC ratio, and no cocaine use (p <0.05). On multivariable analysis, ST elevation (OR 5.67 (2.15 - 14.94), high troponin (OR 1.11 (1.03, 1.19), total cholesterol (OR 1.01 (1.01, 1.03), and glucose levels (OR 1.01 (1.01, 1.01) were statistically significant (p<0.05). There was no significant difference in in-hospital all-cause mortality between the group with and without S-CAD (2.2% and 0.8% respectively; OR 2.75 [0.38, 19.80] p=0.56). Cardiovascular (CV) mortality was 2.2% and 0% respectively (p=0.07). The CV deaths were from STEMI with cardiogenic shock. Conclusions: Total cholesterol and glucose levels were associated with the incidence of S-CAD. STEMI was the presenting syndrome in a high proportion of patients with S-CAD. Despite young age, in-hospital mortality was similar to published rates in the general adult population.

Abstract 17127: Rapid Progression of Conduction System Disease in Suspected Fulminant Nivolumab Myocarditis

Background: Immune checkpoint inhibitors (ICI) have shown efficacy in treating a wide spectrum of malignancies, but have a known risk of cancer therapy related cardiac toxicity. We present a case that demonstrates how conduction system disease can rapidly progress in a patient with suspected nivolumab (PD1) induced fulminant myocarditis. Case: An 82-year-old male with a history of esophageal carcinoma presented with agonal breathing and altered mental status. He had received his second dose of PD1 therapy three days prior. He was intubated and admitted for hypoxic respiratory failure and elevated troponin. His initial EKG demonstrated new marked 1st degree AV block with right bundle branch block (RBBB) morphology. A stat echocardiogram noted an EF of 60-65% with no wall motion abnormalities. Decision-making: On Day 2, Mobitz Type I block was appreciated on telemetry. The patient met criteria for acute myocarditis with his clinical presentation, new conduction system disease, and high sensitivity troponin of 13,000. Given recent PD1 therapy, lack of infectious prodrome, and lack of prior heart disease, suspicion for ICI induced myocarditis was high. High dose steroid therapy was initiated. On Day 3, the patient was noted to have alternating left bundle branch block and RBBB. On Day 4, he progressed to complete heart block, prompting transvenous pacemaker (PM) placement with subsequent permanent PM placement. A repeat echo showed global hypokinesis with an EF of 40-45% and reduced RV function. He also required vasopressor support meeting criteria for fulminant myocarditis. Due to his hemodynamic instability and low clinical suspicion, he did not receive cardiac catheterization. Cardiac MRI and cardiac biopsy were not readily available in this institution. Conclusion: The clinical findings, lack of infectious prodrome, and worsening arrhythmia requiring pacing and vasopressor support, in patient with recent PD1 treatment suggests nivolumab induced fulminant myocarditis. In institutions without advanced testing infrastructure, rapid recognition of progressive conduction system disease may be used as an early marker for diagnosis, treatment initiation, and referral to tertiary care centers for advanced management of fulminant ICI myocarditis.

Abstract 18700: Immune Checkpoint Inhibitor-Related Myocarditis and Overlapping Syndromes

Background: Immune checkpoint inhibitor (ICI)-related myocarditis is a rare adverse effect of ICI's. When accompanied by overlapping myasthenia gravis, prognosis is worsened. While established guidelines aid in the treatment of ICI-associated adverse events, management of overlapping syndromes is complex and challenging. Case description: A 66-year-old man with metastatic renal cell carcinoma recently started on ipilimumab and nivolumab presented with dizziness and diplopia. He had high-grade atrioventricular (AV) block with junctional escape. He had elevated troponin, transaminases, and creatinine kinase. Coronary angiogram showed no evidence of obstructive coronary artery disease. A permanent pacemaker was placed. Cardiac MRI showed no specific features of myocarditis, though quality was limited by pacemaker artifact; left ventricular ejection fraction was 29%. MRI of the orbits showed no signs of extraocular myositis. Acetylcholine receptor (AChR) antibody and muscle-specific kinase (MuSK) antibody was negative. Given ongoing suspicion for ICI-associated adverse events, the patient underwent endomyocardial biopsy. This revealed lymphocytic myocarditis, confirming the diagnosis of ICI-related myocarditis. Despite improvement of troponin, transminases, and creatinine kinase, he developed progressive weakness, dysphagia, and respiratory failure, and died one month after initial presentation. Discussion: We highlight a case of ICI-related myocarditis presenting as high-grade AV block with concurrent hepatitis, myositis, and probable serologic-negative myasthenia gravis (MG). Overlapping syndromes are common in patients with exposure to ICI's, and are associated with significantly higher mortality. Although steroids are first-line for treating ICI-associated adverse events including myocarditis, they can initially lead to acute worsening of MG symptoms. While our patient had laboratory and biomarker improvement of his myocarditis, hepatitis, and myositis, he developed progressive weakness and respiratory failure. Our case highlights the complexity and challenges of managing ICI-related myocarditis and overlapping syndromes, including MG, and its poor prognosis despite prompt treatment.

Abstract 14592: Sepsis Cardiac Edema Related Reversible Injury (SCERRI)

Background: In human septic shock, radionuclide cine angiograms found depression of LVEF and dilatation of the LV (EDV). Peaking at 48h after shock onset, the changes reversed by day 10. Nonsurvivors paradoxically had normal EFs and EDVs. Subsequent TTE studies have not consistently reproduced these findings. To investigate this paradox, we reviewed published clinical studies of cardiac function during sepsis and performed serial CMRIs in a canine model of sepsis-induced cardiac changes. Methods: Clinical studies of sepsis reporting EFs and EDVs in survivors and nonsurvivors were identified from 1980 onward. Sedated purpose-bred beagles (25, 2 y/o) intra-bronchially challenged with S. aureus or saline had serial CMRIs and histology. Results: Mean EF at 24h ranged from 31-69% across 20 clinical studies. Over these studies survivors vs. nonsurvivors, mean EF differences were only 1% (p=0.15; I 2 5%). Twelve clinical sepsis studies reported mean EDVs and showed that survivors had larger EDVs than nonsurvivors (SMD 0.36, p<0.0001; I 2 57%). Like clinical studies, EFs in our S. aureus challenged animal model was similarly depressed in both survivors and nonsurvivors (41% vs. 45%, p=0.34). In animals like humans, LV EDV was significantly higher at 48h in survivors vs . nonsurvivors (40 vs. 30 ml p=0.02) while CVPs and PAOPs were similar throughout (p=ns). From 48 to 96h the septic animals EF recovers towards normal in survivors. CMRIs in septic animals vs. controls showed LV wall thinning with a progressive significant loss of dry mass (~ 1g/24h over 96h) and increased LV wall edema (2-4% total over 96h). There was no histological or biochemical evidence of myocyte necrosis, elevated troponins or BNPs, only endothelial and myocyte edema with mild myofilament loss. Conclusions: Septic shock results in ventricular wall changes not explained by loading conditions or myocardial necrosis. Sepsis-induced cardiac injury is associated with edema as demonstrated by both histopathology and CMRI. The unexpected, acute loss of LV dry mass occurred even as edema increased and the EF recovered, consistent with an adaptive, reparative process. Determining how dry mass is lost and which cells and tissues are affected may clarify mechanisms of cardiac injury and repair in septic shock.

Abstract 16249: A Case of Myocarditis and Pneumonitis Associated With Pembrolizumab Therapy

Introduction: Immune checkpoint inhibitors (ICI) are a novel therapy that activates antitumor immunity but can have varied immune-related adverse effects. As ICI therapy is used to treat malignancy, cases of autoimmune myocarditis and heart failure increase, thought to be due to PD-1 inhibition, which may be potentially fatal. Case presentation: A 37 yo female with history of autoimmune hepatitis and stage III melanoma on Pembrolizumab (ninth cycle 1.5 months prior) presented with chest pain, tachycardia, fatigue, dyspnea, and fever. Lab studies were notable for elevated troponin, lactic acidosis, and disseminated intravascular coagulation (DIC). CT thorax showed asymmetric ground glass opacities, concerning for ICI pneumonitis. Echocardiogram showed an LVEF of 15% with global hypokinesis. She was treated for severe sepsis, DIC, and respiratory failure, temporarily requiring intra-aortic balloon pump. Heart failure guideline-directed medical therapy (GDMT) was started. Clinical presentation was concerning for acute myocarditis related to ICI therapy as a cause for new cardiomyopathy. A cardiac MRI (CMR) revealed subepicardial late gadolinium enhancement (LGE) along the basal inferior/inferolateral wall segments concerning for myocarditis. Corticosteroids with a prolonged taper were started. Endomyocardial biopsy of the septum (EMB) was negative. Her clinical status improved and repeat echo showed LVEF recovery up to 45%. Discussion: Endomyocardial biopsy (EMB) provides definitive diagnosis of myocarditis and is recommended (Class I) for new-onset heart failure with hemodynamic compromise and/or arrhythmias. Although our patient’s EMB was negative (likely due to limitation of sample location), she met the 2013 ESC guideline diagnostic criteria for myocarditis with elevated troponin, functional and structural abnormalities on cardiac imaging. With increased utilization of ICI therapy in the management of aggressive malignancies, it is important to monitor for potentially adverse effects such as autoimmune myocarditis. Standard treatment is prompt initiation of corticosteroids, though newer studies report successful treatment with immunomodulators, such as abatacept and ruxolitinib, if steroids are unsuccessful.

Abstract 14932: Prediction of Pulmonary Embolism Using Random Forest Algorithm: A Study on 917 Patients Over a Period of 1 Year in a New York City Public Hospital

Introduction: Pulmonary Embolism (PE) can be challenging to diagnose. Artificial intelligence (AI)-generated models can help improve the diagnostic accuracy of detecting PE. Aim: Establish the diagnostic accuracy of AI-generated models in predicting PE as compared to routinely used diagnostic predictive tools (Well’s score, YEARS score, and revised Geneva score). Methods: We conducted a single-center retrospective review of patients who underwent computed tomography pulmonary angiography (CTPA) for diagnosing PE over a one-year period. Twenty-five parameters including age, sex, race, BMI, history of deep vein thrombosis or PE, malignancy, hypertension, COPD, CKD, presenting symptoms like chest pain, dyspnea, cough, palpitations, dizziness, lightheadedness/syncope, hemoptysis, fever, pain on palpation of the lower extremity, vitals including heart rate, respiratory rate, oxygen saturation, findings of lower extremity venous duplex, presence of right ventricular dysfunction on echocardiogram, elevated troponin and pro-brain natriuretic peptide were utilized to train the AI model. Random forest algorithms were trained for predicting PE in 80% of the dataset, while the remaining 20% was used to test the AI model. Subsequently, the accuracy of the model was matched with the accuracy of four alternative modalities: clinical judgment of PE being equally or more likely, Well’s score >4, YEARS score ≥1, and revised Geneva score ≥11. CTPA results were used as the gold standard. Analysis was performed using STATA BE/17 and Python 3.8. Results: 917 patients were included in the analysis (median age: 57 years (IQR: 41-68); female: 59%). The AI model correctly classified patients with 84.6% diagnostic accuracy, outperforming every other modality (Figure 1). Conclusion: AI-generated prediction models can be useful in predicting PE with considerable accuracy. Further, large-scale studies are required to validate these results externally.

Abstract 16216: Sociodemographic Disparities in Severity of Multisystem Inflammatory Syndrome in Children: The National MUSIC Study

Introduction: The long-term outcomes after the Multisystem Inflammatory Syndrome in Children (MUSIC) study investigates sequelae in multisystem inflammatory syndrome (MIS-C) post-COVID across 33 US and Canadian sites. Among children with COVID-19, the adjusted MIS-C incidence rate ratios are higher in children who are Hispanic or Black. Our objective was to assess sociodemographic disparities associated with MIS-C severity and adverse outcomes. Methods: This multicenter cross-sectional study included US persons <21 years-old with MIS-C from 6/2020-1/2022. The primary composite outcome of greater illness severity included > 1 findings: vasoactive medications, cardiac dysfunction or elevated troponin, intubation, or mechanical support. Secondary outcomes were days from symptom onset to hospital admission and hospital length of stay (LOS). Predictor variables were patient distance to the hospital, neighborhood social deprivation index (SDI-higher score is worse), race/ethnicity, and non-primary English language. Covariates were age, insurance, asthma, and obesity. Multivariable models used backwards selection at significance p<0.05. Results: There were 1115 MIS-C patients, with a median age of 9 years old (IQR 5.6, 12.7), 39.2% female, 28.1% non-Hispanic Black, 27.8% Hispanic, 47.3% with public insurance, and a median SDI of 54 (IQR 25.0, 82.5). On multivariable analysis, increased odds of more severe illness included Hispanic ethnicity, odds ratio (OR) 1.5 (95% CI 1.1, 2.2); non-Hispanic Black race, OR 1.7 (95% CI 1.1, 2.4) compared to non-Hispanic whites; and ages 13-17 years, OR 3.7 (95% CI 2.4, 5.6) compared to those ages 0-5 years. Longer time to hospital admission was associated with lower SDI (i.e., less deprivation; p=0.009) and further distance from hospital (p=0.006). Risk factors for longer LOS were adolescent age (p=0.002) and non-Hispanic Black race (p=0.018). Asthma and obesity had no association with MIS-C severity. Conclusion: MIS-C severity and adverse outcomes are associated with sociodemographic factors, including being Black and/or Hispanic. Future studies should explore risk mechanisms , including systemic racism, environmental and genetic causes, quality of medical care, or multifactorial interactions.

Abstract 15836: Paraganglioma Presenting as Myocardial Infarction With Decompensated Heart Failure

Description of Case: Paragangliomas are extra-adrenal catecholamine secreting tumors, classically presenting with paroxysmal hypertension, headache, and diaphoresis. However, presentations vary significantly, and can mimic cardiac pathologies including myocardial infarction and aortic dissection. A 52-year-old male with history of hypertension and 1 year of palpitations presented for substernal chest pressure with associated dyspnea, nausea and diaphoresis. He reported two days of cough and nasal congestion, and recent addition of metoprolol for palpitations. His family history was notable for early ACS. On examination, he was tachycardic (140 bpm), hypertensive (220/140 mmHg), and hypoxic requiring non-rebreather mask. EKG revealed sinus tachycardia with 1mm J point elevations in V2 and V3. Chest X-Ray and bedside ultrasound indicated pulmonary edema and reduced systolic function. Nitroglycerin infusion was initiated and he was admitted to the Cardiac ICU. Laboratory testing showed a Troponin-T of 0.15 ng/L (normal <0.01 ng/L), ntPro-BNP 2764 pg/mL, lactic acid 3.2 mmol/L, and respiratory swab positive for Influenza A. A CT Aorta ruled out acute dissection but identified several large retroperitoneal masses. Urgent cardiac catheterization demonstrated non-obstructive CAD. Echocardiography noted severely reduced ejection fraction of 30-35%. With diuresis and alpha blockade, he clinically improved and was discharged. Plasma and urine studies revealed elevated metanephrines. He underwent open paraaortic mass resection and pathology later confirmed paraganglioma. Discussion: With angina, elevated troponins, and acute decompensated heart failure, this presentation was initially concerning for ACS. However, the absence of obstructive CAD warranted further investigation. While concomitant Influenza A infection raised concern for viral myocarditis, abdominal imaging proved crucial in diagnosing paraganglioma.

Abstract 16077: Aortic Valve Thrombus and Acute Right Ventricular Failure in Recent Left Ventricular Assist Device Recipient: A Rare Case

Case reports of aortic root thrombus with embolism leading to right ventricular (RV) failure in patients left ventricular assist devices (LVAD) are extremely rare in the literature, and often result in significant mortality. This is a case of a 52-year-old male who recently underwent destination-therapy HeartMate 3 LVAD implantation, on chronic warfarin, with history of non-ischemic cardiomyopathy, atrial fibrillation, and heparin-induced thrombocytopenia, who presented with chest pain and dyspnea. Initial evaluation was remarkable for tachycardia, troponin of 0.7 ng/dl, BNP 705, and INR 1.68. Argatroban was initiated, along with diuresis for volume overload on examination. Transthoracic echocardiogram showed stable findings with borderline RV dysfunction. On the following day, persistent chest pain and uptrend of troponin to 34 ng/dl were concerning for acute coronary syndrome (ACS), and plans were for left heart catheterization. However, a TEE revealed partial thrombus layering in the aortic valve and sinus of Valsalva with concerns for embolization through the right coronary ostia. RV assessment showed evidence of severe dilation and acute RV failure. Patient underwent emergent RV assist device (RVAD) placement (ProtekDuo and CentriMag) by cardiothoracic surgery. After mechanical RV support, there was progressive improvement of its function, and successful RVAD decannulation was attained. The patient was recently seen in the heart failure clinic with sustained recovery. Cases of aortic root thrombus with embolism leading to ACS in LVAD patients are extremely rare. As in our case, troponin elevation, subtherapeutic INR, and aortic root thrombus, allowed early clinical recognition and appropriate management of patient’s RV failure, which is imperative for successful outcomes in LVAD patients. Aortic valve thrombus should be considered in LVAD patients presenting with ACS, and early invasive strategy without valve assessment should be cautioned.

Abstract 18264: Associations of High-Sensitivity Troponin and Natriuretic Peptide Levels With Cognitive Outcomes in SPRINT

Background: Subclinical elevations in high sensitivity cardiac troponin T (hsc-TnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) identifies a high-risk subgroup with reduction in cardiovascular disease in response to intensive systolic blood pressure (SBP) lowering. However, it remains unknown if these markers also identify subgroups with greater improvement in cognitive outcomes from intensive SBP lowering. Methods: We measured hs-cTnT and NT-proBNP at baseline in Systolic Blood Pressure Intervention Trial (SPRINT). Adjudicated cognitive outcomes were classified as probable dementia (PD) and mild cognitive impairment (MCI). Combined cardiac biomarker categories were defined as elevated, intermediate, and non-elevated. The association of combined biomarker categories with risk of cognitive outcomes was assessed using multivariable Cox proportional hazards models. Heterogeneity in the effect of intensive versus standard SBP lowering on the risk of cognitive outcomes across combined biomarker categories was determined. Results: Of 8,111 SPRINT participants with measured biomarkers and at least one follow-up cognitive assessment, 830 (10.2%) experienced the composite outcome of PD or MCI. After multivariable adjustment, elevated vs. non-elevated cardiac biomarker levels were independently associated with increased risk of composite outcome [HR 95% CI: 1.56 (1.26 - 1.92)]. The effect of intensive SBP lowering on the composite outcome was strongest among participants with non-elevated cardiac biomarkers (see Table). Conclusion: Elevated cardiac biomarkers were associated with higher risk for cognitive impairment. The effect of intensive SBP lowering on preventing cognitive impairment was strongest among patients with non-elevated cardiac biomarkers. This suggests that intensive SBP lowering may be more effective in preventing cognitive impairment in individuals with favorable cardiac biomarker profiles.

Abstract 13592: Addition of the Heart Score to a hsTnT Accelerated Diagnostic Protocol: Effect on Negative Predictive Value at Different hsTnT Thresholds

Background: The majority of pts with CP and low to modest elevations of high sensitivity troponin (hsTn) are safe for discharge from the ED; thus improvement of the negative predictive value (NPV) of the CP accelerated diagnostic protocol (ADP) can have significant impact on ED throughput. Prior studies have examined the role of adding bioclinical risk scores such as the HEART score (HS) to a hsTn ADP. In general these studies suggest the HS does not add to prediction of 30d MACE for pts with low peak troponin levels, i.e. less that the 99 th percentile. Little is known about the effect of the HS on hsTn ADP for higher values of troponin. Research question: How would the addition of the HS affect the NPV of a hsTnT ADP across a range of modest hsTnT elevations? Methods: Retrospective analysis of pts presenting with CP and assessed with a validated hsTnT ADP as well as an EHR-embedded HS decision tool from 5/2022-3/2023. The hsTnT ADP was derived from the ESC guidelines and pts were excluded if peak hsTnT was > 52ng/l (the cutoff for “rule-in”). For calculation of NPV for MACE at 30 days post-discharge pts were grouped by peak hsTnT as <6ng/l, <12ng/l, and <52ng/l. HS was grouped as < 3 (low risk) or >3 (intermediate-high risk). Comparison of NPV results was performed using chi square analysis. Results: Summarized in the Table. The addition of the HS did not significantly change the NPV for 30d MACE for CP pts with peak hsTnT <6ng/l or <12ng/l. In contrast, NPV in pts with peak hsTnT <52ng/l was improved significantly by addition of the HS. Conclusion: The additive value of the HS to a hsTnT ADP for identifying pts safe for ED discharge depends on the range of troponin measurement- HS did not change NPV at very low levels (ie from < limit of quantitation – approx. 99 th percentile) but did improve the NPV at modest elevations between the 99 th percentile and the cutoff for “rule-in” by our ADP. This findings should be considered when designing hsTn CP evaluation protocols that incorporate HS into the algorithm.

Abstract 15960: Mortality Differences Among Myocardial Injury Subtypes in Acute COVID-19, the Omicron Wave Was Different

Introduction: Hospitalization for COVID-19 is often associated with myocardial injury (elevated cardiac troponin [cTn]). In the initial pandemic waves, patients with myocardial injury had increased likelihood of cardiovascular complications and inpatient mortality; however, the differences in impact of distinct subtypes of myocardial injury on mortality is unclear. In addition, little is known about how these outcomes compare with the subsequent, milder, Omicron wave. Methods: Utilizing Mayo Clinic enterprise patients we developed algorithms based on diagnostic/procedural codes, cTn levels, and temporal relationships to positive COVID-19 PCR tests, to determine 5 common subtypes of myocardial injury: stress cardiomyopathy, myocarditis, pericarditis, pulmonary embolism, and myocardial infarction. We examined hospitalized adults with COVID-19; those with elevated cTn designated as cases and others as controls. We fitted Cox models using the following covariates: spline transformed age, sex, race, ethnicity, index date and clinical comorbidities. Patients were analyzed based on admission dates coinciding with either the Alpha-Delta or Omicron waves. Results: Across both wave cohorts, hospitalized patients with acute COVID-19 complicated by myocardial injury had an increased risk of mortality compared to those without ( Figure ). Patients with one of the 5 subtypes examined tended to have higher risk than those in the “other myocardial injury” category. Admission during the Omicron wave, compared to the Alpha-Delta waves, tended to have higher mortality risk in all subtypes except myocarditis. Conclusions: Our algorithms successfully identified subgroups of myocardial injury in patients hospitalized with acute COVID-19 leading to stratification of mortality risk. Surprisingly, among hospitalized patients during the Omicron wave, myocardial injury of most subtypes was tended to have increased risk of mortality compared to the Alpha-Delta waves.