Reperfusion treatment delays amongst patients with painless ST segment elevation myocardial infarction

Abstract

Objective: Early reperfusion therapy in the treatment of ST segment elevation myocardial infarction (STEMI) patients can improve outcomes. Silent myocardial infarction is associated with poor prognosis, but little is known about its effect on treatment delays. We aimed to characterize STEMI patients presenting without complaints of pain to the emergency departments (EDs) in Singapore. Methods: Retrospective data were requested from the Singapore Myocardial Infarction Registry (SMIR), a national level registry in Singapore. Painless STEMI was defined as the absence of pain (chest, back, shoulder, jaw, and epigastric pain) during ED presentation. The primary outcome was door-to-balloon (D2B) time, defined as the earliest time a patient arrived in the ED to balloon inflation. Secondary outcomes were 1-month and 1-year mortality and occurrence of adverse events. Results: From January 2010 to December 2012, the SMIR collected 6412 cases; 10.9% of patients presented without any pain. These patients were older (median age = 75 v. 58 years old), more likely to be females (39.9% v. 16.1%), Chinese (74.9% v. 62.7%), obese (median body mass index [BMI] = 24.5 v. 22.1), and with history of hypertension (71.1% v. 54.6%), diabetes mellitus (48.6% v. 37.0%), and acute myocardial infarction (20.0% v. 12.3%). They had a longer median D2B (80.5 v. 63 minutes, p < 0.001) and a higher occurrence of 30-day (38.4% v. 5.7%) and 1-year mortality rates (47.3% v. 8.5%). Conclusion: A small proportion of STEMI patients presented without any pain to the ED. They tended to have a higher D2B and risks of mortality. Targeted effort is required to improve diagnostic and treatment efficiency in this group. RÉSUMÉContexte: La reperfusion précoce dans le traitement de l'infarctus du myocarde avec sus-décalage du segment ST (STEMI) peut améliorer les résultats cliniques. L'infarctus du myocarde silencieux est associé à un sombre pronostic, mais on en connaît peu sur l'incidence qu'il a sur les retards de traitement. L'étude visait donc à caractériser les patients qui souffraient d'un STEMI, sans ressentir de douleur thoracique, et qui ont consulté dans un service des urgences (SU), à Singapour. Méthode: Il y a eu une collecte de données rétrospectives, tirées du Singapore Myocardial Infarction Registry (SMIR), un registre national établi à Singapour. Le STEMI indolore a été défini comme l'absence de douleur (à la poitrine, dans le dos, à l'épaule, à la mâchoire ou à l'épigastre) durant le séjour au SU. Le principal critère d'évaluation était le temps écoulé depuis la première minute d'arrivée au SU jusqu'au gonflement du ballonnet. Les critères d'évaluation secondaires consistaient en la mortalité au bout de 1 mois et de 1 an et en la survenue d'événements indésirables.

ST-segment elevation myocardial infarction with non-chest pain presentation at the Emergency Department: Insights from the Singapore Myocardial Infarction Registry

“…Non-chest pain presentations of AMI have also been associated with delayed hospital presentation, less aggressive treatment, and increased mortality [6][7][8]. Previous studies have utilised different methods to define the population of patients who present atypically, with many defining them by the absence of pain in any body region [11,13]. This is opposed to the more clinically relevant absence of pain in the chest (non-chest pain STEMI presentation).…”

Using ECG-To-Activation Time to Assess Emergency Physicians’ Diagnostic Time for Acute Coronary Occlusion

“…This requires interpreting the ECG in the context of the patient's symptoms, sometimes taking the time to compare the ECG with a previous one, repeating serial ECGs, or measuring a troponin level. The clinical decision of calling a code STEMI is complicated by patients presenting without classic chest pain, ECGs with other causes of ST elevation, errors in automated interpretation, concerns about false-positive cath lab activation, and evolving criteria for cath lab activation (34)(35)(36)(37)(38)(39)(40)(41)(42)(43). ETA time measures this overall diagnostic time and can suggest and assess strategies to reduce it, from shifting the activation of the cath lab to emergency physician to improving ECG diagnosis of acute coronary occlusion.…”

Nebyliojo Miokardo Infarkto Apibrėžimas, Rizikos Veiksniai Ir Ryšys Su Staigia Mirtimi

“…Europos širdies asociacijos definicijoje išskirti kriterijai netiesiogiai nurodo, kad NMI nėra būklė, reikalaujanti skubios kardiologinės intervencijos; tai patvirtina dauguma tyrimų, rodančių, jog minėta patologija dažniau susijusi su mažesniu nei kliniškai atpažintu MI širdies raumens pažeidimo plotu [3]. Kita vertus, kai kurie autoriai NMI išskiria tik kaip patologiją, susijusią su netipiškais simptomais ar jų nebuvimu (akcentuojant vėlyvą kreipimąsi į gydymo įstaigas, pavėluotą diagnostiką bei gydymą), tačiau nekoreliuojančią su miokardo pažeidimo plotu [4][5][6][7].…”

“…Simptomų, ypač skausmo, nebuvimas pavėlina kreipimąsi į gydymo įstaigas, sunkina MI diagnostiką, prailgina laiką iki reperfuzinės terapijos pradžios (angl. door-to-balloon time) [4], todėl labai tikėtina, kad tokiose situacijose NMI būtų susijęs su dar didesne staigios mirties rizika, nei tipinis MI.…”