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Sandoval, Yader

https://orcid.org/0000-0003-4800-2972

Mayo Clinic

Abbott Northwestern Hospital

Citations 68

Abstract 12578: Development and Validation of a Scoring System For Predicting Technical Failure During Percutaneous Coronary Interventions of Chronic Total Occlusions: The Updated PROGRESS-CTO Score
Karácsonyi, Judit , KUTUZIS, MICHAEL, Sheikh, Abdul Malik, Jaber, Wissam , Rinfret, Stéphane , Yeh, Robert W. , Guindy, Ahmed El, Göktekín, Ömer , Rafeh, Nidal Abi, Jefferson, Brian , Karmpaliotis, Dimitrios, Kirtane, Ajay J. , McEntegart, Margaret , Mastrodemos, Olga , Rangan, Bavana V. , Ungi, Imre , Sandoval, Yader , Simsek, Bahadir , Kostantinis, Spyridon , Alaswad, Khaldoon , Krestyaninov, Oleg V. , Khatri, Jaikirshan J , Poommipanit, Paul B. , Görgülü, Şevket , Jaffer, Farouc A , Patel, Taral N. , Allana, Salman , Burke, M. Nicholas , Brilakis, Emmanouil S.

Circulation | June 15, 2023 | Volume: 146 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.146.suppl_1.12578 Get It

Background: Predicting technical failure in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) can assist with decision making and planning of the procedure. Methods: We analyzed 6,946 CTO PCIs performed between 2016 and June 2022 at 36 international centers in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) and created a score for risk of technical failure. Logistic regression prediction modeling was used to identify independently associated variables with technical failure and model were internally validated with bootstrapping. Results: Mean patient age was 64.0±10 years, 82% were men and technical success was 86%. The following variables were independently associated with technical failure and were included in the final model: age (odds ratio [OR]: 1.08, 95% Confidence Intervals [CI]: [1.00-1.15], p=0.039; age≥ 65 years; 1 point), CTO length (OR: 1.13, 95% CI [1.10, 1.17]; length≥ 20 mm; 1 point), moderate/severe calcification (OR: 1.35, 95% CI [1.17, 1.56]; 1 point), proximal cap ambiguity (OR: 2.25, 95% CI [1.95, 2.59]; 2 points), lack of interventional collaterals (OR: 1.60, 95% CI [1.39, 1.84]; 1 point), and lack of good distal landing zone (OR: 1.51, 95% CI [1.31, 1.75]; 1 point). The resulting score showed acceptable performance on receiver-operating characteristic (ROC) curve, AUC: 0.68 (95% CI [0.67-0.71]). Internal validation with bootstrapping of 1000 samples demonstrated a good agreement with the model, observed AUC: 0.68, (95% bias corrected CI [0.67, 0.70]). PROGRESS-CTO technical failure score and corresponding risk percentage and the percentage of patients in the respective risk group within the PROGRESS-CTO registry are represented in Figure 1. Conclusion: The updated PROGRESS CTO score may be useful for assessing the likelihood of technical failure success in CTO PCI.
Abstract 11505: Predicting In-Hospital All-Cause Mortality in Chronic Total Occlusion Percutaneous Coronary Intervention: PROGRESS-CTO Mortality Score
Karácsonyi, Judit , Göktekín, Ömer , Guindy, Ahmed El, Chandwaney, Raj, Patel, Mitul , Karmpaliotis, Dimitrios, Rangan, Bavana V. , Sandoval, Yader , Choi, James W. , Nicholson, William , Jaber, Wissam , Rinfret, Stéphane , KUTUZIS, MICHAEL, Yeh, Robert W. , Mastrodemos, Olga , Simsek, Bahadir , Kostantinis, Spyridon , Alaswad, Khaldoon , Krestyaninov, Oleg V. , Khelimskii, Dmitrii A. , Davies, Rhian E. , Görgülü, Şevket , Khatri, Jaikirshan J , Jaffer, Farouc A , KUTUZIS, MICHAEL, Tsiafoutis, Ioannis N. , Burke, M. Nicholas , Allana, Salman , Brilakis, Emmanouil S.

Circulation | June 15, 2023 | Volume: 146 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.146.suppl_1.11505 Get It

Introduction: Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is associated with increased risk of periprocedural complications. Estimating the risk of complications facilitates risk-benefit assessment and procedural planning. Methods: We analyzed the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO, NCT02061436) and created a risk score for in-hospital all-cause mortality. Logistic regression prediction modeling was used to identify independently associated variables and the model was internally validated with bootstrapping. Results: Of the 10,480 CTO PCI cases performed between 2012-2022 at 40 US and non-US centers, in-hospital mortality occurred in 47 (0.45%). The final prediction model identified 4 independent predictors of mortality: Age ≥65 years, Odds Ratio [OR]: 2.83 (95% confidence interval [CI], 1.30-6.16), 1-point; Left ventricular ejection fraction ≤45%, OR: 2.13 (95% CI, 1.14-3.98), 1-point; Moderate-severe calcification, OR: 2.45 (95% CI, 1.18-5.08), 1-point; and Antegrade dissection re-entry, OR: 2.81 (95% CI, 1.06-7.43), 1-point; or Retrograde strategy, OR: 3.51 (95% CI, 1.67-7.37), 1-point; with a bootstrap corrected c-statistics of 0.71 (95% confidence interval: 0.63-0.81). The calculated risk percentages for mortality based on the PROGRESS-CTO mortality score ranged from 0.05-2.42% for mortality, and 63% of patients in the PROGRESS-CTO cohort had PROGRESS-CTO mortality score of 1 or 2, corresponding to a mortality risk of 0.1-0.5% (Figure 1). Conclusions: The PROGRESS-CTO in-hospital mortality risk score can facilitate risk-benefit assessment and procedural planning in patients undergoing CTO PCI.
Abstract 11108: Implementation of High-Sensitivity Cardiac Troponin Assays in the United States: A Report From the NCDR Chest Pain - MI Registry
McCarthy, Cian P. , Li, Shuang , Wang, Tracy Y , Raber, Inbar , Sandoval, Yader , Smilowitz, Nathaniel R. , Kontos, Michael C. , Apple, Fred S. , Daniels, Lori B. , Newby, L. Kristin , Jaffe, Allan S. , Daniels, Lori B , Wasfy, Jason H. , Pandey, Ambarish , Lemos, James A. de , Jaffe, Allan S. , Januzzi, James Louis

Circulation | June 15, 2023 | Volume: 146 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.146.suppl_1.11108 Get It

Introduction: High-sensitivity cardiac troponin (hs-cTn) assays were first approved for use in the U.S. in 2017. They are the guideline preferred biomarker to evaluate patients with acute chest pain. Few data exist regarding implementation of hs-cTn assays in the U.S. Hypothesis: We hypothesize that use of hs-cTn assays has increased over time and that patients assessed with hs-cTn have a shorter length of stay (LOS) and similar use of cardiac testing. Methods: We examined trends in implementation of hs-cTn assays among participating hospitals in the NCDR Chest Pain MI Registry from 1/1/2019 through 9/30/2021. Excluding STEMI patients, associations between hs-cTn use, in-hospital diagnostic imaging, and patient outcomes were assessed using logistic or negative binomial regression models. Results: Among 550 participating hospitals with 251,000 patients in the registry, implementation of hs-cTn assays increased from 3.3% in Q1, 2019 to 32.6% in Q3, 2021 (P trend <0.0001; Figure ). Implementation was similar by hospital size, type, and geographic location. hs-cTn use was associated with more echocardiography among patients with NSTE-ACS (82% vs. 75%; aOR: 1.43, 95% CI, 1.19-1.73) but not in low-risk chest pain. hs-cTn use was associated with decreased odds of invasive coronary angiography in low-risk patients (3.7% vs. 4.5%; aOR: 0.73, 95% CI, 0.58-0.92) but similar use in NSTE-ACS. There was no association between hs-cTn use and non-invasive stress/CTCA testing. Among NSTE-ACS patients, hs-cTn use was not associated with PCI, CABG, or in-hospital mortality. Use of hs-cTn was associated with shorter LOS (47.6 hours vs. 48 hours; IRR: 0.96, 95% CI, 0.93-0.98). Conclusions: Although implementation of hs-cTn among U.S. hospitals is increasing, most U.S hospitals continue to use less-sensitive troponin assays. hs-cTn use was associated with shorter LOS overall, greater use of echocardiography in NSTE-ACS, and lower use of invasive angiograms in low-risk patients.
Artificial intelligence–augmented electrocardiography for left ventricular systolic dysfunction in patients undergoing high-sensitivity cardiac troponin T
Knott, Jonathan D , Attia, Zachi I. , Ola, Olatunde , Mehta, Ramila A. , Akula, Ashok , Hodge, David O. , Gulati, Rajiv , Friedman, Paul A. , Jaffe, Allan S. , Sandoval, Yader , Attia, Zachi I , Friedman, Paul A , Sandoval, Yader , Michieli, Laura De , Jaffe, Allan S.

European Heart Journal. Acute Cardiovascular Care | December 20, 2022 | Volume: 12 | Issue: 2 | Pages: 106-114

10.1093/ehjacc/zuac156 Get It

Abstract Aims Our goal was to evaluate a previously validated artificial intelligence–augmented electrocardiography (AI-ECG) screening tool for left ventricular systolic dysfunction (LVSD) in patients undergoing high-sensitivity-cardiac troponin T (hs-cTnT). Methods and results Retrospective application of AI-ECG for LVSD in emergency department (ED) patients undergoing hs-cTnT. AI-ECG scores (0–1) for probability of LVSD (left ventricular ejection fraction ≤ 35%) were obtained. An AI-ECG score ≥0.256 indicates a positive screen. The primary endpoint was a composite of post-discharge major adverse cardiovascular events (MACEs) at two years follow-up. Among 1977 patients, 248 (13%) had a positive AI-ECG. When compared with patients with a negative AI-ECG, those with a positive AI-ECG had a higher risk for MACE [48 vs. 21%, P &lt; 0.0001, adjusted hazard ratio (HR) 1.39, 95% confidence interval (CI) 1.11–1.75]. This was largely because of a higher rate of deaths (32 vs. 14%, P &lt; 0.0001; adjusted HR 1.26, 95% 0.95–1.66) and heart failure hospitalizations (26 vs. 6.1%, P &lt; 0.001; adjusted HR 1.75, 95% CI 1.25–2.45). Together, hs-cTnT and AI-ECG resulted in the following MACE rates and adjusted HRs: hs-cTnT &lt; 99th percentile and negative AI-ECG: 116/1176 (11%; reference), hs-cTnT &lt; 99th percentile and positive AI-ECG: 28/107 (26%; adjusted HR 1.54, 95% CI 1.01–2.36), hs-cTnT &gt; 99th percentile and negative AI-ECG: 233/553 (42%; adjusted HR 2.12, 95% CI 1.66, 2.70), and hs-cTnT &gt; 99th percentile and positive AI-ECG: 91/141 (65%; adjusted HR 2.83, 95% CI 2.06, 3.87). Conclusion Among ED patients evaluated with hs-cTnT, a positive AI-ECG for LVSD identifies patients at high risk for MACE. The conjoint use of hs-cTnT and AI-ECG facilitates risk stratification.
Artificial intelligence-enabled electrocardiographic algorithm for the detection of left ventricular dysfunction in emergency department patients undergoing high-sensitivity cardiac troponin T
Knott, J D, Ola, Oluwabukola Mary , Akula, Ashok , Mehta, Ramila A. , Dworak, Marshall , Lobo, R , Hodge, Dave, Tak, Tahir , Cagin, C, Friedman, Perry , Gulati, R, Jaffe, Allan S. , Sandoval, Yader , Michieli, Laura De , Knott, Jonathan D , Attia, Zachi I. , Ola, O, Friedman, P, Jaffe, Allan S.

European Heart Journal | October 14, 2022 | Volume: 43 | Issue: Supplement_2 | Pages: No page available

10.1093/eurheartj/ehac544.1330 Get It

Abstract Background Artificial intelligence-augmented electrocardiogram (AI-ECG) algorithms have been developed from the standard 12-lead ECG and validated for the recognition of left ventricular systolic dysfunction (LVSD), defined as LV ejection fraction (LVEF)≤35%. Whether AI-ECG facilitates identification of LVSD and is associated with adverse outcomes in emergency department (ED) patients undergoing high-sensitivity cardiac troponin (hs-cTnT) testing is uncertain. Purpose To investigate the diagnostic and prognostic performance of AI-ECG in ED patients undergoing hs-cTnT measurement. Methods Observational US cohort study of ED patients undergoing hs-cTnT measurement. Cases with hs-cTnT increases &gt;sex-specific 99th percentiles were adjudicated following the Fourth Universal Definition of Myocardial Infarction (MI). Post-discharge major adverse cardiac events (MACE) included death, MI, heart failure (HF) hospitalization, stroke or transient ischemic attack, and new onset atrial fibrillation/flutter during 2-years follow-up. The AI-ECG network output, which is a continuous number between 0–1, that provides a probability of LVSD, was obtained for each patient from the first ECG during the index presentation. An AI-ECG threshold of ≥0.256 indicates a positive screen that correlates with a high probability of LVSD. Results Among 1977 patients, 1729 (87%) had a negative AI-ECG screen, while 248 (13%) had a positive AI-ECG screen. Patients with a positive AI-ECG screen were older and had more comorbidities. As compared to patients with hs-cTnT≤99th percentile in whom AI-ECG was positive in 5.8%, those with hs-cTnT&gt;99th percentile had a positive AI-ECG in 22% of cases (p&lt;0.0001). Based on adjudicated diagnoses, the frequency of a positive AI-ECG was 20% in myocardial injury, 38% in type 1 MI, and 20% in type 2 MI. At 2-years follow-up, as compared to patients with a negative AI-ECG, those with a positive AI-ECG had a higher risk for MACE (48% vs. 21%, p&lt;0.0001, adjusted HR 1.39, 95% CI 1.11–1.75) (Figure 1), mainly because of more deaths (43% vs. 30%, p=0.004) and HF hospitalizations (36% vs. 13%, p&lt;0.0001). A positive AI-ECG was associated with a higher risk for MACE (60% vs. 41%, p&lt;0.0001, adjusted HR 1.30, 95% CI 1.02–1.64) in those with hs-cTnT increases &gt;99th percentile, but not in those without hs-cTnT increases. Among patients with an echocardiogram during index presentation or within 30-days (n=452), the diagnostic accuracy of AI-ECG for LVEF ≤35% was 81.4% (95% CI 77.5, 84.9) with a negative predictive value of 96.5% (95% CI 94.0, 98.2). A normal LVEF (&gt;50%) was observed in 87% of those with a negative AI ECG, whereas in those with a positive AI-ECG LVEF was reduced (&lt;50%) in 60%. Conclusions Among ED patients evaluated with hs-cTnT, a positive AI-ECG screen for LVSD identifies patients at high risk of MACE. These findings are largely because of more deaths and HF hospitalizations in those with hs-cTnT increases &gt;sex-specific 99th percentiles. Funding Acknowledgement Type of funding sources: None.
Contemporary Techniques for Femoral and Radial Arterial Access in the Cardiac Catheterization Laboratory
Gladden, James D., Gulati, Rajiv , Sandoval, Yader

Reviews in Cardiovascular Medicine | September 16, 2022 | Volume: 23 | Issue: 9 | Pages: No page available

10.31083/j.rcm2309316 Get It

Safe and efficient arterial access is critical for optimal patient outcomes and procedural success in the cardiac catheterization laboratory. Because of the lower risk for vascular and bleeding complications, as well as patient comfort, transradial access has become the predominant approach for diagnostic coronary angiography and percutaneous coronary intervention. Transfemoral access, however, is still required for selected complex percutaneous coronary interventions, mechanical circulatory support, and structural heart procedures. The use of adjunctive technology and techniques such as ultrasound guidance and micropuncture can be combined with fluoroscopy and palpation to improve outcomes associated with vascular access. The importance of optimal access techniques has augmented due to increasing volume of structural heart and mechanical circulatory support procedures requiring large bore sheaths. In this document we review the contemporary techniques for femoral and radial access in the cardiac catheterization laboratory.
High-Sensitivity Cardiac Troponin and the 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guidelines for the Evaluation and Diagnosis of Acute Chest Pain
Sandoval, Yader , Apple, Fred S. , Mahler, Simon A. , Jaffe, Allan S. , Jaffe, Allan S. , Body, Richard , Collinson, Paul

Circulation | August 15, 2022 | Volume: 146 | Issue: 7 | Pages: 569-581

10.1161/circulationaha.122.059678 Get It

The 2021 American Heart Association/American College of Cardiology/American Society of Echocardiography/American College of Chest Physicians/Society for Academic Emergency Medicine/Society of Cardiovascular Computed Tomography/Society for Cardiovascular Magnetic Resonance guidelines for the evaluation and diagnosis of acute chest pain make important recommendations that include the recognition of high-sensitivity cardiac troponin (hs-cTn) as the preferred biomarker, endorsement of 99th percentile upper reference limits to define myocardial injury, and the use of clinical decision pathways, as well as acknowledgment of the uniqueness of women and other patient subsets. Details on how to integrate hs-cTn into clinical practice are less extensively addressed. Clinicians should be aware of some of the analytical aspects related to hs-cTn assays regarding the limit of detection and the limit of quantitation and how they are used clinically, especially for the single sample strategy to rule out acute myocardial infarction. Likewise, it is important for clinicians to understand issues related to the derivation of the 99th percentile upper reference limit; the value of sex-specific 99th percentile upper reference limits; how to use changing concentrations (deltas) to facilitate diagnosis and risk stratification of patients with suspected acute coronary syndrome, including the differentiation of acute from chronic myocardial injury; and how to best integrate the use of hs-cTn with clinical decision pathways. With the use of hs-cTn, conditions such as type 2 myocardial infarction become more common, whereas others such as unstable angina become less frequent but still occur. Sections relating to these issues are included.
Intravascular lithotripsy in chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS‐CTO registry
Kostantinis, Spyridon , Karácsonyi, Judit , Benton, Stewart M., Nicholson, William , Rinfret, Stéphane , Jaber, Wissam , Raj, Leah, Sandesara, Pratik B. , Basir, Mir B. , Young, Laura , Rafeh, Nidal Abi, Patel, Mitul , Kerrigan, Jimmy , Haddad, Elias V., Sandoval, Yader , Sheikh, Abdul Malik, ElGuindy, Ahmed , Göktekín, Ömer , Mastrodemos, Olga , Rangan, Bavana V. , Simsek, Bahadir , Sandesara, Pratik B , Basir, Mir B , Khatri, Jaikirshan J , Young, Laura D , Jaffer, Farouc A , Kerrigan, Jimmy L , Dattilo, Phil , Sandoval, Yader , Brilakis, Emmanouil S , Kostantinis, Spyridon , Megaly, Michael S. , Davies, Rhian E. , Alaswad, Khaldoon , Schimmel, Daniel R. , Burke, M. Nicholas , Brilakis, Emmanouil S.

Catheterization and Cardiovascular Interventions | August 2, 2022 | Volume: 100 | Issue: 4 | Pages: 512-519

10.1002/ccd.30354 Get It

AbstractBackgroundThe use of intravascular lithotripsy (IVL) in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study.MethodsWe analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 82 CTO PCIs that required IVL at 14 centers between 2020 and 2022.ResultsDuring the study period, IVL was used in 82 of 3301 (2.5%) CTO PCI procedures (0.4% in 2020 and 7% in 2022; p for trend < 0.001). Mean patient age was 69 ± 11 years and 79% were men. The prevalence of hypertension (95%), diabetes mellitus (62%), and prior PCI (61%) was high. The most common target vessel was the right coronary artery (54%), followed by the left circumflex (23%). The mean J‐CTO and PROGRESS‐CTO scores were 2.8 ± 1.1 and 1.3 ± 1.0, respectively. Antegrade wiring was the final successful crossing strategy in 65% and the retrograde approach was used in 22%. IVL was used in 10% of all heavily calcified lesions and 11% of all balloon undilatable lesions. The 3.5 mm lithotripsy balloon was the most commonly used balloon (28%). The mean number of pulses per lithotripsy run was 33 ± 32 and the median duration of lithotripsy was 80 (interquartile range: 40−103) seconds. Technical and procedural success was achieved in 77 (94%) and 74 (90%) cases, respectively. Two (2.4%) Ellis Class 2 perforations occurred after IVL use and were managed conservatively.ConclusionIVL is increasingly being used in CTO PCI with encouraging outcomes.
Major adverse cardiovascular events after diagnosis of myocardial injury and types 1 and 2 myocardial infarction
Knott, Jonathan D , Ola, Olatunde , Akula, Ashok , Mehta, Ramila A. , Dworak, Marshall , Crockford, Erika, Lobo, Ronstan , Rastas, Nicholas, Karturi, Swetha, Wohlrab, Scott, Hodge, David O. , Grube, Eric , Tak, Tahir , Cagin, Charles , Gulati, Rajiv , Jaffe, Allan S. , Sandoval, Yader , Sandoval, Yader , Michieli, Laura De , Grube, Eric, Jaffe, Allan S.

European Heart Journal. Acute Cardiovascular Care | June 18, 2022 | Volume: 11 | Issue: 7 | Pages: 546-557

10.1093/ehjacc/zuac075 Get It

Abstract Aims Limited US outcome data exist among patients with myocardial injury and types 1 and 2 myocardial infarction (MI) evaluated with high-sensitivity cardiac troponin (hs-cTn). Methods and results This is an observational US cohort study of emergency department (ED) patients undergoing hs-cTnT measurement. Cases with ≥1 hs-cTnT increase &gt;99th percentile were adjudicated following the Fourth Universal Definition of MI. Post-discharge major adverse cardiovascular events (MACE) included death, MI, heart failure (HF) hospitalization, stroke or transient ischaemic attack, and new-onset atrial fibrillation or flutter during 2 years follow-up. Among 2002 patients, 857 (43%) had ≥1 hs-cTnT &gt;99th percentile. Among these, 702 (81.9%) had myocardial injury, 64 (7.5%) had type 1 MI, and 91 (10.6%) had type 2 MI. Compared with patients without myocardial injury, type 2 MI [8.4 vs. 50%; adjusted hazard ratio (HR) 2.31, 95% confidence interval (CI) 1.49–3.58] and myocardial injury (8.4 vs. 47%; adjusted HR 3.13, 95% CI 2.39–4.09) had a higher risk of MACE, in large part because of death and HF hospitalizations. Compared with patients with type 1 MI, type 2 MI (23 vs. 50%; adjusted HR 2.24; 95% CI 1.23–4.10) and myocardial injury (23 vs. 47%; adjusted HR 2.02; 95% CI 1.20–3.40) also have a higher risk of MACE. Conclusion Among unselected US ED patients undergoing hs-cTnT measurement, most increases are due to myocardial injury, and type 2 MI is more frequent than type 1 MI. Patients with myocardial injury and type 2 MI have morbid outcomes, in large part due to death and HF.
Rapid Exclusion of Acute Myocardial Injury and Infarction With a Single High-Sensitivity Cardiac Troponin T in the Emergency Department: A Multicenter United States Evaluation
Sandoval, Yader , Lewis, Bradley R., Mehta, Ramila A. , Ola, Olatunde , Knott, Jonathan D , Michieli, Laura De , Akula, Ashok , Lobo, Ronstan , Gharacholou, S. Michael , Dworak, Marshall , Crockford, Erika, Rastas, Nicholas, Grube, Eric , Karturi, Swetha, Wohlrab, Scott, Hodge, David O. , Tak, Tahir , Cagin, Charles , Gulati, Rajiv , Jaffe, Allan S. , Lewis, Bradley R , De Michieli, Laura , Dworak, Marshall , Gulati, Rajiv , Jaffe, Allan S. , Yang, Eric H. , Grube, Eric

Circulation | May 10, 2022 | Volume: 145 | Issue: 23 | Pages: 1708-1719

10.1161/circulationaha.122.059235 Get It

Background: There are good data to support using a single high-sensitivity cardiac troponin T (hs-cTnT) below the limit of detection of 5 ng/L to exclude acute myocardial infarction. Per the US Food and Drug Administration, hs-cTnT can only report to the limit of quantitation of 6 ng/L, a threshold for which there are limited data. Our goal was to determine whether a single hs-cTnT below the limit of quantitation of 6 ng/L is a safe strategy to identify patients at low risk for acute myocardial injury and infarction. Methods: The efficacy (proportion identified as low risk based on baseline hs-cTnT<6 ng/L) of identifying low-risk patients was examined in a multicenter (n=22 sites) US cohort study of emergency department patients undergoing at least 1 hs-cTnT (CV Data Mart Biomarker cohort). We then determined the performance of a single hs-cTnT<6 ng/L (biomarker alone) to exclude acute myocardial injury (subsequent hs-cTnT >99th percentile in those with an initial hs-cTnT<6 ng/L). The clinically intended rule-out strategy combining a nonischemic ECG with a baseline hs-cTnT<6 ng/L was subsequently tested in an adjudicated cohort in which the diagnostic performance for ruling out acute myocardial infarction and safety (myocardial infarction or death at 30 days) were evaluated. Results: A total of 85 610 patients were evaluated in the CV Data Mart Biomarker cohort, among which 24 646 (29%) had a baseline hs-cTnT<6 ng/L. Women were more likely than men to have hs-cTnT<6 ng/L (38% versus 20%, P <0.0001). Among 11 962 patients with baseline hs-cTnT<6 ng/L and serial measurements, only 1.2% developed acute myocardial injury, resulting in a negative predictive value of 98.8% (95% CI, 98.6–99.0) and sensitivity of 99.6% (95% CI, 99.5–99.6). In the adjudicated cohort, a nonischemic ECG with hs-cTnT<6 ng/L identified 33% of patients (610/1849) as low risk and resulted in a negative predictive value and sensitivity of 100% and a 30-day rate of 0.2% for myocardial infarction or death. Conclusions: A single hs-cTnT below the limit of quantitation of 6 ng/L is a safe and rapid method to identify a substantial number of patients at very low risk for acute myocardial injury and infarction.