Browsing by Author "Singer, Adam J"
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Item Open Access Ideal high sensitivity troponin baseline cutoff for patients with renal dysfunction.(The American journal of emergency medicine, 2022-06) Limkakeng, Alexander T; Hertz, Julian; Lerebours, Reginald; Kuchibhatla, Maragatha; McCord, James; Singer, Adam J; Apple, Fred S; Peacock, William F; Christenson, Robert H; Nowak, Richard MItem Open Access International, multicenter evaluation of a new D-dimer assay for the exclusion of venous thromboembolism using standard and age-adjusted cut-offs.(Thrombosis research, 2018-04-05) Parry, Blair Alden; Chang, Anna Marie; Schellong, Sebastian M; House, Stacey L; Fermann, Gregory J; Deadmon, Erin K; Giordano, Nicholas J; Chang, Yuchiao; Cohen, Jason; Robak, Nancy; Singer, Adam J; Mulrow, Mary; Reibling, Ellen T; Francis, Samuel; Griffin, S Michelle; Prochaska, Jürgen H; Davis, Barbara; McNelis, Patricia; Delgado, Joao; Kümpers, Philipp; Werner, Nikos; Gentile, Nina T; Zeserson, Eli; Wild, Philipp S; Limkakeng, Alexander T; Walters, Elizabeth Lea; LoVecchio, Frank; Theodoro, Daniel; Hollander, Judd E; Kabrhel, ChristopherWe sought to determine the test characteristics of an automated INNOVANCE D-dimer assay for the exclusion of pulmonary embolism (PE) and deep venous thrombosis (DVT) in emergency department (ED) patients using standard and age-adjusted cut-offs.Cross-sectional, international, multicenter study of consecutive patients with suspected DVT or PE in 24 centers (18 USA, 6 Europe). Evaluated patients had low or intermediate Wells PE or DVT scores. For the standard cut-off, a D-dimer result <500 ng/ml was negative. For the age adjusted cut-off, we used the formula: Age (years) ∗ 10. The diagnostic standard was imaging demonstrating PE or DVT within 3 months. We calculated test characteristics using standard methods. We also explored modifications of the age adjustment multiplier.We included 3837 patients and excluded 251. The mean age of patients evaluated for PE (n = 1834) was 48 ± 16 years, with 676 (37%) male, and 1081 (59%) white. The mean age of evaluated for DVT (n = 1752) was 53 ± 16 years, with 710 (41%) male, and 1172 (67%) white. D-dimer test characteristics for PE were: sensitivity 98.0%, specificity 55.4%, negative predictive value (NPV) 99.8%, positive predictive value (PPV) 11.4%, and for DVT were: sensitivity 92.0%, specificity 44.8%, NPV 98.8%, PPV 10.3%. Age adjustment increased specificity (59.6% [PE], 51.1% [DVT]), but increasing the age-adjustment multiplier decreased sensitivity without increasing specificity.INNOVANCE D-dimer is highly sensitive and can exclude PE and DVT in ED patients with low- and intermediate- pre-test probability. Age-adjustment increases specificity, without increasing false negatives.Item Open Access Outcomes in ED patients with non-specific ECG findings and low high-sensitivity troponin.(Journal of the American College of Emergency Physicians open, 2022-12) Alshaikh, Lamees M; Apple, Fred S; Christenson, Robert H; deFilippi, Christopher R; Limkakeng, Alexander T; McCord, James; Nowak, Richard M; Singer, Adam J; Peacock, W FrankBackground
Although some emergency department risk stratification tools consider non-specific ECG findings as an aid in disposition decisions, their clinical value in patients with an initially low high-sensitivity cardiac troponin I (hsTnI) is unclear.Objective
Our purpose was to determine if non-specific ECG (ns-ECG) findings are associated with 30-day major adverse cardiac events (MACE) in ED patients presenting with suspected acute coronary syndromes (ACS) who have a low initial hsTnI.Methods
Using the prospective Siemens Atellica hsTnI Food and Drug Administration submission observational database, we conducted a retrospective cohort study of the association between ns-ECG findings (defined as left bundle branch block [LBBB], ST depression [STD], or T-wave inversions [TWI]) and 30-day MACE (death, myocardial infarction, heart failure hospitalization, or coronary revascularization). Eligible patients presented with suspected ACS to one of 29 US EDs from April 2015 to April 2016, had stable vital signs, a blood sample for hsTnI (Siemen's Atellica, Siemens Healthineers, Inc, Malvern, PA) obtained at 1, 3, and 6 hours after ED presentation, and were followed for 30 days. The relationship between 30-day outcome, initial hsTnI, and ns-ECG was evaluated using chi-square testing.Results
Of 2676 enrolled, 1313 patients met the inclusion criteria and are included in the analysis. Median (interquartile range) age was 62 years (54, 72), 54% were male, with 56% white, and 39% African American. Median (interquartile range) times from symptom onset to presentation and presentation to specimen collection were 92 (0, 216) and 146 (117, 177) minutes, respectively. The most common presenting symptoms were chest pain (84%), followed by dyspnea (9%). ECG findings were categorized as T-wave inversion or non-specific T wave changes (42%), ST depression ns-ECG ST changes (16%), or LBBB (2%). Thirty-day MACE occurred in 72 (5.5%) patients, with coronary revascularization (35 patients, 2.7%) and heart failure (25 patients, 1.9%) being the most frequent outcomes. In patients with an initial hsTnI below the limit of quantitation (LOQ) of 2.5 ng/L (n = 449), there was no association between ns-ECG changes and 30-day MACE (P = 0.42). If the hsTnI was ≥LOQ (2.5 ng/L), there were increased rates of 30-day MACE and ns-ECG findings (P = 0.01).Conclusion
In ED suspected ACS patients without unstable vital signs, and an initial hsTnI less than the LOQ (2.5 ng/L), ns-ECG findings are not associated with 30-day major adverse cardiac events. The use of ns-ECG findings in ACS disposition should be considered in the context of hsTnI levels.Item Open Access Outpatient versus observation/inpatient management of emergency department patients rapidly ruled-out for acute myocardial infarction: Findings from the HIGH-US study.(American heart journal, 2021-01) Nowak, Richard M; Jacobsen, Gordon; Limkakeng, Alexander; Peacock, William F; Christenson, Robert H; McCord, James; Apple, Fred S; Singer, Adam J; deFilippi, Christopher RBackground
The actual Emergency Department (ED) dispositions of patients enrolled in observational studies and meeting criteria for rapid acute myocardial infarction (AMI) rule-out are unknown. Additionally, their presenting clinical profiles, cardiac testing/treatments received, and outcomes have not been reported.Methods
Patients in the HIGH-US study (29 sites) that ruled-out for AMI using a high-sensitivity cardiac troponin I 0/1-hour algorithm were evaluated. Clinical characteristics of patients having ED discharge were compared to patients placed in observation or hospital admitted (OBS/ADM). Reports of any OBS/ADM cardiac stress test (CST), cardiac catheterization (Cath) and coronary revascularization were reviewed. One year AMI/death and major adverse cardiovascular event rates were determined.Results
Of the 1,020 ruled-out AMI patients 584 (57.3%) had ED discharge. The remaining 436 (42.7%) were placed in OBS/ADM. Patients with risk factors for AMI, including personal or family history of coronary artery disease, hypertension, previous stroke or abnormal ECG were more often placed in OBS/ADM. 175 (40.1%) had a CST. Of these 32 (18.3%) were abnormal and 143 (81.7%) normal. Cath was done in 11 (34.3%) of those with abnormal and 13 (9.1%) with normal CST. Of those without an initial CST 85 (32.6%) had Cath. Overall, revascularizations were performed in 26 (6.0%) patients. One-year AMI/death rates were low/similar (P = .553) for the groups studied.Conclusions
Rapidly ruled-out for AMI ED patients having a higher clinician perceived risk for new or worsening coronary artery disease and placed in OBS/ADM underwent many diagnostic tests, were infrequently revascularized and had excellent outcomes. Alternate efficient strategies for these patients are needed.Item Open Access Performance of Novel High-Sensitivity Cardiac Troponin I Assays for 0/1-Hour and 0/2- to 3-Hour Evaluations for Acute Myocardial Infarction: Results From the HIGH-US Study.(Annals of emergency medicine, 2020-07) Nowak, Richard M; Christenson, Robert H; Jacobsen, Gordon; McCord, James; Apple, Fred S; Singer, Adam J; Limkakeng, Alexander; Peacock, William F; deFilippi, Christopher RSTUDY OBJECTIVE:We determine the accuracy of high-sensitivity cardiac troponin I (hs-cTnI), European-derived, rapid, acute myocardial infarction, rule-out/rule-in algorithms applied to a US emergency department (ED) population. METHODS:Adults presenting to the ED with suspected acute myocardial infarction were included. Plasma samples collected at baseline and between 40 and 90 minutes and 2 and 3 hours later were analyzed in core laboratories using the Siemens Healthineers hs-cTnI assays. Acute myocardial infarction diagnosis was independently adjudicated. The sensitivity, specificity, and negative and positive predictive values for rapid acute myocardial infarction rule-out/rule-in using European algorithms and 30-day outcomes are reported. RESULTS:From 29 US medical centers, 2,113 subjects had complete data for the 0/1-hour algorithm analyses. With the Siemens Atellica Immunoassay hs-cTnI values, 1,065 patients (50.4%) were ruled out, with a negative predictive value of 99.7% and sensitivity of 98.7% (95% confidence interval 99.2% to 99.9% and 96.3% to 99.6%, respectively), whereas 265 patients (12.6%) were ruled in, having a positive predictive value of 69.4% and specificity of 95.7% (95% confidence interval 63.6% to 74.7% and 94.7% to 96.5%, respectively). The remaining 783 patients (37.1%) were classified as having continued evaluations, with an acute myocardial infarction incidence of 5.6% (95% confidence interval 4.2% to 7.5%). The overall 30-day risk of death or postdischarge acute myocardial infarction was very low in the ruled-out patients but was incrementally increased in the other groups (rule-out 0.2%; continued evaluations 2.1%; rule-in 4.8%). Equivalent results were observed in the 0/2- to 3-hour analyses and when both algorithms were applied to the hs-cTnI ADVIA Centaur measurements. CONCLUSION:The European rapid rule-out/rule-in acute myocardial infarction algorithm hs-cTnI cut points can be harmonized with a demographically and risk-factor diverse US ED population.