Author’s Disclosure Statement: The authors report no actual or potential conflict of interest in relation to this article.
Dr. Worley is Instructor, Department of Emergency Medicine, NewYork-Presbyterian Hospital/Columbia University, New York, NY. Dr. Mattson is Resident, Department of Emergency Medicine, NewYork-Presbyterian Hospital, New York, NY. Dr. Bhatt is Assistant Professor, Department of Emergency Medicine, NewYork-Presbyterian Hospital/Columbia University, New York, NY.
In a second prospective observational cohort of 1458 patient visits, a score of 0 correlated to a 1.7% incidence of adverse outcomes.28 In 2008, Body et al sought to increase the relative weight of EKG and biomarker factors to 5 (instead of 1) in a study of 796 patients, positing that these factors have more importance in the ED setting.29 Comparing the modified TIMI to the original, the modified instrument improved the area under curve (AUC) from 0.77 to 0.87.29 In follow-up validation studies, the modified score has an improved AUC, but the incidence of adverse outcomes at score 0 remains at about 2% for both modified and original score.30,31
In 2010, Hess et al performed a systematic review and meta-analysis of the studies that prospectively validated the TIMI score. They evaluated 10 validation studies, encompassing 17,265 patients across 5 countries, and found a strong linear relation between the TIMI score and adverse cardiac events.32 At TIMI score of 0, the incidence of cardiac events was 1.8%, with sensitivity of 97.2% and specificity of 25%. Subsequently, the ADAPT trial designed a diagnostic protocol consisting of TIMI risk assessment, EKG, and 0- and 2-hour troponin I biomarkers to find ED patients eligible for safe, early discharge.33 Of the 1975 patients, 20% were classified as low risk and eligible for early discharge, in that they had TIMI score of 0, a non-ischemic ECG, and negative troponins. Only one patient had a MACE at 30 days, giving the protocol a sensitivity of 99.7%, specificity of 23.4%, and negative predictive value of 99.7%.33
As the TIMI and HEART scores are both used to evaluate ED chest pain patients, several studies have sought to compare them. In 2015, Cartlon et al published a comparison of 5 established risk scores and 2 troponin assays in 963 patients: modified Goldman, TIMI, GRACE, HEART, and Vancouver Chest Pain Rule in combination with troponin T and I.34 The investigators found that a negative troponin T plus either TIMI score of 0 or a HEART score ≤3 gave a negative predictive value of greater than 99.5% with more than 30% of patients able to be discharged safely.34 In 2017, a comparison of the GRACE, HEART, and TIMI scores in 1833 chest pain patients found the HEART score identified more low risk patients than either of its comparators and had the highest AUC at 0.86.35 Other trials have similarly found HEART outperforming TIMI.36
Comment: The TIMI score was not specifically designed for ED use but has been adapted to serve this purpose. To the EP assessing the undifferentiated chest pain patient, the TIMI score uses clinical variables that may seem curious (eg, aspirin use) or impossible for EPs to ascertain (eg, presence or degree of stenosis). Even for patients with a score of 0, the risk for adverse outcomes remains stubbornly at the 2% level, similar to the original low risk HEART score findings.
Wells’ Criteria for Pulmonary Embolism
The diagnosis of pulmonary embolism (PE) is often challenging, requiring the use of multiple ED resources for timely diagnosis, and is therefore well suited for clinical decision instruments. The Wells’ Criteria were derived from a cohort of 1260 patients using logistic regression to identify 7 significant variables:
Clinical signs and symptoms of deep vein thrombosis (DVT): 3 PE is the most likely diagnosis: 3 Heart rate >100: 1.5 Immobilization or surgery in the previous 4 weeks: 1.5 Previously diagnosed DVT or PE: 1.5 Hemoptysis: 1 Malignancy with treatment within 6 months or palliative: 1
