High-Sensitivity Cardiac Troponin Levels in Supraventricular Tachyarrhythmias.

BACKGROUND: High-sensitivity cardiac troponin assays have provided a significant contribution for the early diagnosis of cardiovascular events. However, elevated cardiac troponin levels may occur in other clinical situations as supraventricular tachyarrhythmias with concerns about the mechanism of this elevation. OBJECTIVES AND METHODS: The goal of this study was to describe the performance of high-sensitivity cardiac troponin T (hs-cTnT) assay in patients presenting to the emergency department with a primary diagnosis of supraventricular tachyarrhythmia and to evaluate its relation with cardiovascular events during follow-up. RESULTS: One hundred patients were included; mean age was 64 ± 12 years and 59.8% were men. The most common arrhythmia at admission was atrial fibrillation (68%), followed by atrial flutter (16%) and reentrant tachycardia (16%). The results of the first determination of hs-cTnT were positive (>14 ng/L) in 44.2% of the patients and the second determination was positive in 50.7% of the cases. The variation between the first and the second troponin levels was 1 (0-5) ng/L, and was >7 ng/L in 24.6% of the cases, with a clear trend toward higher troponin values in reentrant tachycardias. Four events were reported at 30 days; in all the cases the patients had presented atrial fibrillation and there were no significant differences in hs-cTnT values. CONCLUSIONS: There are a significant number of patients with supraventricular tachyarrhythmias who present elevated hs-cTnT levels. The association of this elevation with cardiovascular events seems to be very low.

Predictors of conversion of recent-onset atrial fibrillation treated with vernakalant.

BACKGROUND: Vernakalant is an available drug for the treatment of recent-onset atrial fibrillation, producing conversion between 55% and 87% of the patients treated. In this sense, little is known about the predictors of conversion with this agent. The aim of our study was to analyze the predictors of conversion in our 2-year experience using vernakalant for the treatment of recent-onset atrial fibrillation. METHODS: One hundred twenty-one patients with recent-onset atrial fibrillation without hemodynamic impairment received pharmacological treatment with vernakalant. Clinical variables, history of cardiovascular diseases, and echocardiographic data were recorded. RESULTS: Mean age was 58.1 ± 13.9 years and 13.4% of patients had structural heart disease. Conversion to sinus rhythm was achieved in 84.5% of patients, and 46% required the second dose of vernakalant. After analyzing the predictors of conversion, the presence of structural heart disease was significantly larger in the group without conversion (35.3 vs 9.7%; P = 0.02). The mean ejection fraction in the group with conversion was 61.05 ± 5.7% versus 54.9 ± 8.4% in the group without conversion (P = 0.016). After dichotomizing the variable ejection fraction, patients with ejection fraction <55% had a lower conversion rate (P = 0.001). CONCLUSION: In our study, the absence of any kind of structural heart disease and preserved systolic function were associated with greater conversion rate with vernakalant.

Algorithm for probable acute coronary syndrome using high-sensitivity troponin T assay vs fourth-generation troponin T assay.

BACKGROUND: Chest pain represents between 5% and 10% of annual visits to emergency departments (EDs) and near 25% of hospitalizations. Characterization of chest pain is sometimes difficult, and strategies should focus on preventing inappropriate discharge of patients with acute coronary syndrome. The goal of our study is to compare negative predictive value of the algorithm in the chest pain unit using the fourth-generation troponin T assay (4GTT) vs high-sensitivity troponin T assay (HSTT). METHODS: We included 600 patients with probable acute coronary syndrome, who were discharged from the chest pain unit without an acute coronary syndrome: 300 patients in the 4GTT group and 300 patients in the HSTT group. Clinical and laboratory variables were analyzed. All the patients were followed up at 30 days, and the cardiovascular events were recorded. RESULTS: Major cardiac events occurred in only 3 (1.2%) in the HSTT group vs 5 (1.7%) in the 4GTT group (P, nonsignificant). The negative predictive value was 99% in both groups. Emergency department length of stay was 4.3 ± 2.6 hours in HSTT group vs 10 ± 3.4 hours in the 4GTT group (P = .01). CONCLUSION: The algorithm in the chest pain unit using HSTT showed to have the same negative predictive value as the algorithm with the 4GTT but with a shorter stay in the ED.

High-Sensitivity Troponin T For The Risk Assessment Of Patients With Acute Atrial Fibrillation.

Elevations of high-sensitivity troponin T (Hs-TnT) in the setting of acute atrial fibrillation (AF) are not clearly understood. This study evaluated factors associated with these elevations and its prognostic implication. We prospectively included 413 consecutive patients who presented to our institution with acute AF. The median Hs-TnT on admission was 12 ng/l and 39.4% had values above the 99th percentile. At 1-year, AF recurrence occurred in 38.3% of patients, and MACE in 5.6%. Hs-TnT levels were not associated with AF reversion (p 0.869) or with 1-year AF recurrence (p 0.132) but they were with MACE (12 vs 24 ng/l, p 0.001). Thus, Hs-TnT was a strong predictor of MACE (HR 3.486, 95% CI 1.256-5.379, p 0.009) in this population. In conclusion, Hs-TnT elevation was frequently observed in patients with acute AF, and although it was not associated with AF reversion or recurrence, it was highly predictive of MACE at 1-year.

The HEART score in the era of the European Society of Cardiology 0/1-hour algorithm.

BACKGROUND: The European Society of Cardiology's 0/1-hour algorithm improves the early triage of patients towards "rule-out" or "rule-in" of non-ST-segment elevation myocardial infarction. The HEART score is a risk stratification tool for patients with undifferentiated chest pain. We sought to evaluate the performance of the European Society of Cardiology 0/1-hour algorithm and the HEART score to evaluate chest pain patients in the emergency department. METHODS: In this prospective study, we applied the European Society of Cardiology 0/1-hour algorithm and the HEART score in 1355 consecutive patients who presented to the emergency department with symptoms suggestive of acute coronary syndrome without ST-segment elevation. Patients were followed for non-ST-segment elevation myocardial infarctions and major adverse cardiac events at 30 days: death, non-ST-segment elevation myocardial infarction, or unplanned coronary revascularization. RESULTS: The European Society of Cardiology 0/1-hour algorithm classified 921 (68.0%) patients as "rule-out" and the HEART score classified 686 (50.6%) patients as "low-risk". The 30-day incidence of non-ST-segment elevation myocardial infarctions was 0.32% in the European Society of Cardiology 0/1-hour algorithm "rule-out" patients versus 0.29% in the HEART score "low-risk" patients (p=0.75). The rate of major adverse cardiac events was 7.7% in the European Society of Cardiology 0/1-hour algorithm "rule-out" patients versus 1.1% in the HEART score "low-risk" patients (p<0.001). CONCLUSION: The European Society of Cardiology 0/1-hour algorithm identified more patients with low risk of non-ST-segment elevation myocardial infarctions at 30 days whereas for major adverse cardiac events, the HEART score had a greater capacity to detect low-risk patients.

Outcome of Applying the ESC 0/1-hour Algorithm in Patients With Suspected Myocardial Infarction.

BACKGROUND: The European Society of Cardiology (ESC) recommends the 0/1-h algorithm for rapid triage of patients with suspected non-ST-segment elevation myocardial infarction (MI). However, its impact on patient management and safety when routinely applied is unknown. OBJECTIVES: This study sought to determine these important real-world outcome data. METHODS: In a prospective international study enrolling patients presenting with acute chest discomfort to the emergency department (ED), the authors assessed the real-world performance of the ESC 0/1-h algorithm using high-sensitivity cardiac troponin T embedded in routine clinical care and its associated 30-day rates of major adverse cardiac events (MACE) (the composite of cardiovascular death and MI). RESULTS: Among 2,296 patients, non-ST-segment elevation MI prevalence was 9.8%. In median, 1-h blood samples were collected 65 min after the 0-h blood draw. Overall, 94% of patients were managed without protocol violations, and 98% of patients triaged toward rule-out did not require additional cardiac investigations including high-sensitivity cardiac troponin T measurements at later time points or coronary computed tomography angiography in the ED. Median ED stay was 2 h and 30 min. The ESC 0/1-h algorithm triaged 62% of patients toward rule-out, and 71% of all patients underwent outpatient management. Proportion of patients with 30-day MACE were 0.2% (95% confidence interval: 03% to 0.5%) in the rule-out group and 0.1% (95% confidence interval: 0% to 0.2%) in outpatients. Very low MACE rates were confirmed in multiple subgroups, including early presenters. CONCLUSIONS: These real-world data document the excellent applicability, short time to ED discharge, and low rate of 30-day MACE associated with the routine clinical use of the ESC 0/1-h algorithm for the management of patients presenting with acute chest discomfort to the ED.

Predicción de riesgo de sufrir un síndrome coronario agudo mediante un algoritmo de Machine Learning (ANGINA) / A Machine Learning Algorithm to Predict Risk for Acute Coronary Syndrome

RESUMEN Introducción: Las consultas por dolor torácico son frecuentes en los servicios de emergencias médicas (SEM). Aún no se ha identificado una estrategia diagnóstica que utilice tanto los datos objetivos como los subjetivos del dolor. Objetivos: Evaluar un clasificador de machine learning para predecir el riesgo de presentar un síndrome coronario agudo (SCA) sin elevación del segmento ST, en pacientes que consultan a un SEM con dolor torácico. Material y métodos: Se analizaron 161 pacientes que consultaron al SEM con dolor torácico. Se registró mediante un clasificador de machine learning las variables objetivas y subjetivas de caracterización del dolor. Resultados: La edad promedio fue de 57 mas/menos 12, 72,7% masculinos eran de sexo masculino y 17,4 % presentaban evento coronario previo. El 57,8% presentaba un síndrome coronario agudo con una incidencia de IAM de 29,8%, de los cuales requirieron revascularización por ATC el 35%, y CRM el 9,9% en el período de seguimiento a 30 días. Como modelo de clasificación se utilizó un Random Forest Classifier que presentó un área bajo la curva ROC de 0,8991, sensibilidad de 0,8552, especificidad de 0,8588 y una precisión de 0,8441. Las variables predictoras más influyentes fueron peso (p = 0,002), edad (p = 5,011e-07), intensidad del dolor (p = 3,0679e-05), tensión arterial sistólica (p = 0,6068) y características subjetivas del dolor (p = 1,590e-04). Conclusiones: Los clasificadores de machine learning son una herramienta útil a fin de predecir el riesgo de sufrir un síndrome coronario agudo a 30 días de seguimiento.

ABSTRACT Background: Consultations for chest pain are common in emergency medical services (EMS). A diagnostic strategy using both objective and subjective pain has not been identified yet. Objective: To evaluate a machine learning classifier as a tool for prediction of the risk of presenting a non-ST segment elevation acute coronary syndrome (ACS) in patients consulting an SEM with chest pain. Methods: 161 patients consulting SEM with chest pain were analyzed. Objective variables of the patient and subjective variables of pain characterization were recorded during the triage stage by means of a machine learning classifier. Results: The mean age was 57.43±12 years, 75% male and 16% had prior cardiovascular disease. 57.8% presented an ACS with an incidence of 29.8%, which 35% required PCI and 9.9% CRM in a 30-day follow-up period. A Random Forest Classifier was used as a classification model. The Random Forest Classifier presented an area under the ROC curve of 0.8991, sensitivity of 0.8552, specificity of 0.8588 and precision of 0.8441. The most strongest predictor variables were weight (p=0.002), age (p=5.011e-07), pain intensity (p=3.0679e-05), systolic blood pressure (p = 0.6068) and subjective pain characteristics (p=1.590e-04). Conclusions: Machine learning classifiers are a useful tool for predicting the risk of acute coronary syndrome at 30 days follow-up period.

Vernakalant: Perception of state of health in patients with a recent-onset atrial fibrillation.

BACKGROUND: Vernakalant is a new, safe and effective drug used intravenously, which has proved to be more rapid in converting recent onset atrial fibrillation (AF) to sinus rhythm compared to placebo, amiodarone, propafenone, and flecainide in clinical studies. Until now no study has been conducted comparing the perception of state of health in patients who received vernakalant versus propafenone or flecainide for conversion of recent-onset AF. The aim of our study is to compare the change of perception of state of health from screening to hour 2 in patients treated with vernakalant and propafenone or flecainide for conversion of recent-onset AF. METHODS: Eighty hemodynamically stable patients with recent onset AF without structural heart disease were prospectively included. A single oral dose of propafenone 600 mg was administered to 30 patients, 30 patients received intravenous vernakalant and the remaining 20 patients received a single oral dose of flecainide 300 mg. Clinical, laboratory variables and perception of state of health from screening to hour 2 treated with these drugs measured by the EQ-5 D quality-of-life assessments visual analog scale were recorded. RESULTS: Baseline characteristics were similar in the three groups. Treatment with vernakalant resulted in a significantly greater improvement in patient perception of state of health at hour 2 compared with propafenone and flecainide. In the vernakalant group, a mean increase (from baseline) of 12.1 points was seen compared with a mean increase of 5.4 points in the propafenone group or 5.2 points in flecainide group (p < 0.01). CONCLUSIONS: The change of perception of state of health from screening to hour 2 treated with vernakalant had a significantly statistical improvement compared with propafenone or flecainide for conversion recent-onset AF.

Resultados de los primeros pacientes con sospecha de síndrome coronario agudo evaluados con el algoritmo de 1 hora propuesto por la Sociedad Europea de Cardiología / Results of the First Patients with Suspected Acute Coronary Syndrome Evaluated with the 1-hour Algorithm Proposed by the European Society of Cardiology

RESUMEN Introducción: La Sociedad Europea de Cardiología recomienda para la evaluación del dolor torácico un algoritmo con medición seriada de dos troponinas de alta sensibilidad separadas por una hora. Sin embargo, la alta eficacia y seguridad solo se han estimado según supuestos basados en modelos teóricos. Probamos por primera vez su desempeño en nuestro medio cuando se integra en la rutina diaria. Métodos: Estudio prospectivo unicéntrico que incluyó a pacientes no seleccionados que presentaban sospecha de infarto sin elevación del ST en el servicio de emergencias, a los que se les practicó el algoritmo SEC 0/1h utilizando troponina T de alta sensiblidad. Se evaluó el comportamiento en términos de incidencia a 30 días de los eventos de infarto agudo de miocardio, muerte cardiovascular y el combinado de infarto agudo de miocardio, muerte o revascularización coronaria. Resultados: Se incluyeron 1351 pacientes con una edad media de 61 ± 14 años, 12,4% de diabéticos y 35,8% de evento coronario previo. La tasa de infarto agudo de miocardio fue del 11% con una mortalidad del 0,29%. De acuerdo con la aplicación del algoritmo, 917 pacientes fueron catalogados como "externar" (67%); 270, como "observar" (20%); y 164, como "internar" (13%). La tasa del evento infarto agudo de miocardio resultó del 0,3% en "externar"; del 7%, en "observar"; y del 77,4%, en "internar" (p < 0,001). Por su lado, la muerte o revascularización coronaria resultó de 7,7% en "externar"; del 17,7%, en "observar"; y del 80,4%, en "internar" (p < 0,001). Conclusiones: El algoritmo de 1 hora presentó una buena capacidad para estratificar a pacientes que consultan con sospecha de infarto agudo de miocardio con un gran valor predictivo negativo para excluir el evento de infarto a los 30 días, aunque dicho valor disminuye cuando el evento considerado es la necesidad de revascularización coronaria.

ABSTRACT Background: The European Society of Cardiology (ESC) recommends an algorithm for the evaluation of chest pain with serial measurement of two high sensitivity troponins separated by one hour. However, the high efficacy and safety of the algorithm has only been estimated according to assumptions based on theoretical models. We tested for the first time its performance in the real world by incorporating it into the daily routine of our center. Methods: This is a prospective, single center study using the ESC 0/1h algorithm with high sensitivity troponin T on unselected patients who presented at the emergency department with suspected non-ST-segment elevation acute myocardial infarction. Efficacy and safety were assessed in terms of the 30-day incidence of acute myocardial infarction, cardiovascular death and the composite of acute myocardial infarction, death or coronary revascularization. Results: A total of 1,351 patients were included in the study. Mean age was 61±14 years, 12.4% were diabetics and 35.8% had previous history of coronary events. The rate of acute myocardial infarction was 11% and the rate of mortality 0.29%. According to the application of the algorithm, 917 patients were catalogued as "rule out" (67%), 270 as "observe" (20%) and 164 as "rule in" (13%). The rate of acute myocardial infarction was 0.3% in "rule out", 7% in "observe" and 77.4% in "rule in" (p <0.001). Moreover, death or coronary revascularization was 7.7% in "rule out", 17.7% in "observe" and 80.4% in "rule in" (p <0.001). Conclusions: The 1-hour algorithm showed a good capacity to stratify patients presenting with suspicion of acute myocardial infarction and a high negative predictive value to exclude infarction at 30 days, although this capacity decreases when the event considered is the need for coronary revascularization.

Conversion of Recent-Onset Atrial Fibrillation: Which Drug is the Best?

Introduction: Vernakalant is a new, safe and effective drug used intravenously. It has proven to be more rapid in converting recent onset atrial fibrillation (AF) to sinus rhythm compared to placebo, amiodarone, propafenone and flecainide in clinical studies with few patients. At present no study has been conducted comparing these three drugs with a more substantial number of patients. The aim of our study is to compare the time to conversion to sinus rhythm, hospital stay and adverse events between vernakalant versus flecainide and propafenone in patients with a recent-onset AF. Materials and Methods: 150 hemodynamically stable patients with recent onset AF without structural heart disease were prospectively included. A single oral dose of propafenone 600 mg was administered to 50 patients; 50 patients received intravenous vernakalant; and 50 patients received a single oral dose of flecainide 300 mg. Clinical and laboratory variables were recorded. Results: Baseline characteristics were similar in the three groups.Time to conversion to sinus rhythm was 12 minutes in the vernakalant group versus 151 minutes in the propafenone group and 162 minutes in flecainide group (p< 0.01) The hospital stay was 243 minutes in the vernakalant group versus 422 minutes in the propafenone group and 410 minutes in flecainide group (p<0.01) (Figure 2). No adverse events were reported. Conclusion: The time to conversion to sinus rhythm and hospital stay were statistically shorter in vernakalant group compared to flecainide and to propafenone. There were no adverse events in the three groups.

Propafenone versus vernakalant for conversion of recent-onset atrial fibrillation.

INTRODUCTION: An oral loading dose of propafenone 600 mg is used in our center as in other places around the world for conversion of recent-onset atrial fibrillation (AF) in patients without structural heart disease. Vernakalant is a novel, safe, and effective drug used intravenously and has proved to be more rapid in converting recent-onset AF to sinus rhythm compared with placebo and amiodarone. There is no study that compares vernakalant with propafenone. The aim of our study is to compare the time taken for conversion of recent-onset AF in patients treated with vernakalant and propafenone. METHODS: Thirty-six hemodynamically stable patients with recent-onset AF without structural heart disease were prospectively included. A single oral dose of propafenone 600 mg was administered to 19 patients and 17 received intravenous vernakalant. Clinical and laboratory variables, conversion rate, and time to conversion were recorded. RESULTS: Baseline characteristics were similar in both groups. Time to conversion to sinus rhythm was of 166 min (120-300) in the propafenone group versus 9 min (6-18) in the vernakalant group (P = 0.0001). Conversion rate was of 78% in the propafenone group at 8 h and of 93% in the vernakalant group at 2 h; yet, this difference was not statistically significant (P = 0.4). Time to conversion had a direct impact in hospital stay, which was 43% shorter in the vernakalant group (P = 0.0001). CONCLUSION: Time to conversion of AF to sinus rhythm was significantly shorter in the vernakalant group compared with the propafenone group and was associated with shorter hospital stay.

Flecainide versus vernakalant for conversion of recent-onset atrial fibrillation.

BACKGROUND: An oral single dose of flecainide is used worldwide for conversion of recent onset atrial fibrillation (AF) in hemodynamically stable patients without structural heart disease. Vernakalant is a novel, rapid drug, which is used intravenously, with proven effectiveness and safety compared to placebo and amiodarone in randomized clinical trials. The aim of our study was to compare the time taken for conversion of recent onset AF in patients treated with vernakalant or flecainide. METHODS: This is a sequential study in which 32 hemodynamically stable patients with recent onset AF without structural heart disease were prospectively and consecutively included in two periods, one for each drug. A single oral dose of flecainide 300 mg was administered to 15 patients and 17 patients received intravenous vernakalant. Clinical and laboratory variables, conversion rate and time to conversion were recorded. RESULTS: Baseline characteristics were similar in both groups. Time to conversion to sinus rhythm was of 163 min (120-300) in the flecainide group versus 10 min (6-18) in the vernakalant group (p=0.0001). CONCLUSION: Time to conversion of AF to sinus rhythm was significantly shorter in the vernakalant group compared with the flecainide group, and was associated with shorter hospital stay. This reduction in hospital stay length may produce benefits in patients' medical care, costs and welfare.

Evaluación de un nuevo algoritmo diagnóstico para el síndrome coronario agudo con determinación de troponina T de alta sensibilidad / Evaluation of a New Diagnostic Algorithm for Acute Coronary Syndrome Using High-Sensitivity Troponin T Assay

Introducción El dolor precordial representa el 5% al 10% de las consultas anuales en los departamentos de emergencias; su diagnóstico suele ser dificultoso y a ello se le suma el problema que implican la externación de pacientes con patología coronaria aguda o las internaciones innecesarias. Esto ha llevado al desarrollo de diferentes sistemáticas para la evaluación de estos pacientes. Objetivo Validar en términos de seguridad y tiempos de estadía hospitalaria un nuevo algoritmo incorporado en nuestro centro que incluye la medición de troponina T de alta sensibilidad en pacientes con sospecha de síndrome coronario agudo. Material y métodos Se incluyeron 528 pacientes que consultaron en el servicio de emergencias con sospecha de síndrome coronario agudo y se les realizó el protocolo de unidad de dolor. Se analizaron variables clínicas, de laboratorio y el resultado de las pruebas funcionales efectuadas. En todos los pacientes se efectuó seguimiento a los 30 días. Resultados El 90,7% de los pacientes fueron externados luego de la observación y al seguimiento el 1,25% había presentado un evento cardíaco, representado por angioplastia coronaria e internación por síndrome coronario agudo; la especificidad del algoritmo global para el diagnóstico de síndrome coronario agudo fue del 97% y el valor predictivo negativo fue del 99%. El tiempo de estadía en el servicio de emergencias del total de los pacientes fue de 4,5 ± 2,5 horas. Conclusión El nuevo algoritmo incorporado en nuestro centro con determinación de troponina T de alta sensibilidad en pacientes con sospecha de síndrome coronario agudo demostró que es seguro al evitar la externación de pacientes que cursaban un síndrome coronario agudo y, a la vez, requiere una corta estadía hospitalaria en el servicio de emergencias.(AU)

Introduction Chest pain represents 5 to 10% of annual visits to emergency departments. Its diagnosis is sometimes difficult, with the added problem of inappropriate discharge of patients with acute coronary syndrome or unnecessary hospitalizations. This has led to the development of different algorithms for the evaluation of these patients. Objective The aim of this study was to validate, in terms of safety and length of hospital stay, a novel algorithm incorporated in our center, which includes measurement of high-sensitivity troponin T in patients with suspected acute coronary syndrome. Methods The study included 528 consecutive patients attending the emergency department with suspected acute coronary syndrome and evaluated according to the chest pain unit protocol. Clinical and laboratory variables and functional tests were analyzed. Follow-up at 30 days was performed in all the patients. Results After observation, 90.7% of the patients were discharged and 1.25% presented a cardiovascular event during follow-up, represented by percutaneous coronary intervention and hospitalization due to acute coronary syndrome. The specificity of the global algorithm for the diagnosis of acute coronary syndrome was 97% with a negative predictive value of 99%. Emergency department length of stay was 4.5 ± 2.5 hours for all the patients. Conclusion The novel algorithm incorporated in our center with measurement of high-sensitivity troponin T in patients with suspected acute coronary syndrome has proved to be safe, as it prevents the discharge of patients with acute coronary syndrome and at the same time reduces emergency department length of stay.(AU)

Evaluación de un nuevo algoritmo diagnóstico para el síndrome coronario agudo con determinación de troponina T de alta sensibilidad / Evaluation of a New Diagnostic Algorithm for Acute Coronary Syndrome Using High-Sensitivity Troponin T Assay

Introducción El dolor precordial representa el 5% al 10% de las consultas anuales en los departamentos de emergencias; su diagnóstico suele ser dificultoso y a ello se le suma el problema que implican la externación de pacientes con patología coronaria aguda o las internaciones innecesarias. Esto ha llevado al desarrollo de diferentes sistemáticas para la evaluación de estos pacientes. Objetivo Validar en términos de seguridad y tiempos de estadía hospitalaria un nuevo algoritmo incorporado en nuestro centro que incluye la medición de troponina T de alta sensibilidad en pacientes con sospecha de síndrome coronario agudo. Material y métodos Se incluyeron 528 pacientes que consultaron en el servicio de emergencias con sospecha de síndrome coronario agudo y se les realizó el protocolo de unidad de dolor. Se analizaron variables clínicas, de laboratorio y el resultado de las pruebas funcionales efectuadas. En todos los pacientes se efectuó seguimiento a los 30 días. Resultados El 90,7% de los pacientes fueron externados luego de la observación y al seguimiento el 1,25% había presentado un evento cardíaco, representado por angioplastia coronaria e internación por síndrome coronario agudo; la especificidad del algoritmo global para el diagnóstico de síndrome coronario agudo fue del 97% y el valor predictivo negativo fue del 99%. El tiempo de estadía en el servicio de emergencias del total de los pacientes fue de 4,5 ± 2,5 horas. Conclusión El nuevo algoritmo incorporado en nuestro centro con determinación de troponina T de alta sensibilidad en pacientes con sospecha de síndrome coronario agudo demostró que es seguro al evitar la externación de pacientes que cursaban un síndrome coronario agudo y, a la vez, requiere una corta estadía hospitalaria en el servicio de emergencias.

Introduction Chest pain represents 5 to 10% of annual visits to emergency departments. Its diagnosis is sometimes difficult, with the added problem of inappropriate discharge of patients with acute coronary syndrome or unnecessary hospitalizations. This has led to the development of different algorithms for the evaluation of these patients. Objective The aim of this study was to validate, in terms of safety and length of hospital stay, a novel algorithm incorporated in our center, which includes measurement of high-sensitivity troponin T in patients with suspected acute coronary syndrome. Methods The study included 528 consecutive patients attending the emergency department with suspected acute coronary syndrome and evaluated according to the chest pain unit protocol. Clinical and laboratory variables and functional tests were analyzed. Follow-up at 30 days was performed in all the patients. Results After observation, 90.7% of the patients were discharged and 1.25% presented a cardiovascular event during follow-up, represented by percutaneous coronary intervention and hospitalization due to acute coronary syndrome. The specificity of the global algorithm for the diagnosis of acute coronary syndrome was 97% with a negative predictive value of 99%. Emergency department length of stay was 4.5 ± 2.5 hours for all the patients. Conclusion The novel algorithm incorporated in our center with measurement of high-sensitivity troponin T in patients with suspected acute coronary syndrome has proved to be safe, as it prevents the discharge of patients with acute coronary syndrome and at the same time reduces emergency department length of stay.