The relationship between total ischemic time and mortality in patients with STEMI: every second counts

Abstract

We read with great interest the recently published article in the October 2016 issue of JACC Cardiovasc Interv by Rashid et al. (1). Briefly, it was a retrospective, single center study that analyzed ST-elevation myocardial infarction (STEMI) patients with symptom onset <12 hours. Patients with primary percutaneous intervention (PCI) were compared with those who received fibrinolytic therapy prior to arrival at the hospital due to non-availability of primary PCI. The authors concluded that the pharmaco-invasive strategy was associated with similar rates of the composite endpoint of mortality, reinfarction, or stroke as compared with a primary PCI strategy. There was propensity for increased bleeding in the pharmaco-invasive group, with a significant fraction (approximately 1 in every 21 patients) having major bleeding, including intracranial bleeding.Non-inferiority of pharmaco-invasive strategy compared to primary PCI strategy in this study emphasizes the importance of total ischemic time. These are patients who received fibrinolytic therapy within few minutes of presentation at the initial hospital (with no primary PCI capability) which could have led to dissolution of the thrombus and re-canalization of the culprit artery, and hence reduction of the total ischemic time. The similar outcomes between the groups despite a big difference in the door-to-balloon times are most likely due to the shortening of the total ischemic time by the administration of fibrinolysis. However, we must not ignore the limitations of the study. There was a disparity between the control group vs. test group, i.e., 236 pharmaco-invasive strategy patients vs. 980 primary PCI patients (approximately 4:1 ratio), which may have influenced the statistical model. As the patients were not randomized, unknown confounders may have affected the results owing to the retrospective nature of the study. For example, the median time from symptom onset to arrival at the first hospital was significantly shorter in the pharmacoinvasive group, which may have favored these patients. The study only studied the in-hospital results and the long-term outcomes are not known. The infarct size as measured by peak creatinekinase MB levels, was significantly higher in pharmacoinvasive group, and we already know that the peak infarct size is related to worse long-term outcomes from several large trials in the past (2). However, this difference may not be clinically significant as the composite of mortality, reinfarction, or stroke was similar between the two groups. Nevertheless, the long-term outcomes are unknown in these patients. Also, the infarct zone at risk was not defined so that the selection bias for patients who were destined to have larger infarcts was not eliminated. To better define the zone at risk an MRI study like the one done by Eitel et al. would have been very useful (3). Furthermore, the pharmacologic regimen used for the groups were different. The pharmaco-invasive group patients received a lower dose of clopidogrel and an infusion of heparin...

Analysis of the hospitalization time impact on hospital mortality from acute myocardial infarction

“…The results obtained in our study demonstrated the effect of the total time of hospitalization of patients on mortality in patients with AMI. This confirms the findings of a number of previous studies, in which the total time of myocardial ischemia was also an important predictor of death both in the hospital and in the long-term period [15,16].…”

Expert assessment of the suitability of treatment and diagnostic measures in providing emergency care to patients with acute coronary syndrome

“…However, in re-cent years, new data and new treatment and diagnostic approaches have emerged that allow more successful treatment of patients with ACS [1,13]. Today, the importance of early contact of the patient with a health worker and the beginning of reperfusion therapy is not in doubt [2,8]. That is why the effective organization of treatment, close interaction of prehospital and subsequent stages of medical care becomes especially important.…”

“…The influence of various factors on the course and prognosis in patients with acute coronary syndrome (ACS) with ST segment elevation has been proven [1,2]. Such factors include demographic indicators, such as gender, age [3], anamnesis data (death of parents from heart disease, self-administration of antianginal drugs [3,4], hemodynamic parameters), blood pressure, heart rate [5,6], etiology and pathogenesis (nature of coronary artery occlusion, severity of coronary artery disease) [7], time factors (therapeutic window up to 12 h from the moment of clinical symptoms of the disease or a time interval up to 24 h from the moment of development of the clinical picture of ACS for percutaneous coronary interventions (PCI) [8,9].…”

“…A patient with ACS who was hospitalized in a specialized cardiac hospital for the first 90 minutes after the onset of an angina attack has a better chance of success [2]. The results of the analysis of time indicators of patient care at the prehospital stage suggest that 90 minutes should include the time from the onset of pain to the receipt and processing of the call by the emergency department of the emergency medical service (EMS), the time of transfer of the call to the EMS, time spent on providing emergency medical care at the scene, time of transportation of the patient to a specialized health care institution [6,10,11].…”

Various Delays and Its Determinants in the Timeline of St-Segment Elevation Myocardial Infarction

“…10 It is well established that the time of presentation of STEMI from the onset of chest pain and timely treatment determines prognosis of patient. [11][12][13][14][15] For a number of reasons the time between emergency room (ER) arrival and symptom onset was the primary concern among the cardiologists and efforts have made it possible to brought it down to less than 90 minutes of recommended cutoff in most of the situations. 10,16 However, up until recent years the scientific community was less attentive towards the pre-hospital delays.…”