The Physician's Role in Minimizing Prehospital Delay in Patients at High Risk for Acute Myocardial Infarction: Recommendations from the National Heart Attack Alert Program

A dramatically decreased mortality rate has been seen with early administration of thrombolytic therapy in acute myocardial infarction in several large, randomized clinical trials [1-6]. The administration of thrombolytic drugs within 1 hour of symptom onset results in little or no evidence of myocardial damage in many patients [7-10]. An effect of time to treatment has also been seen in patients with primary angioplasty [11], but more data are needed. If patients and their families seek and receive expeditious care, many effective interventions are available for the early management of acute myocardial infarction, acute cardiac ischemia, potentially fatal arrhythmia, and cardiogenic shock. Not all patients with acute myocardial infarction receive the benefits of these dramatic advances in treatment. Data from a national registry of more than 240 000 patients with acute myocardial infarction showed that only 35% of patients who had a diagnosis of acute myocardial infarction at discharge received thrombolytic therapy [12]. Data from the National Registry of Myocardial Infarction [12] and the TIMI (Thrombolysis in Myocardial Infarction) 9 Registry [13] indicate that patients who did not receive a thrombolytic agent were also not treated aggressively with such drugs as aspirin, -blockers, and heparin, all of which have been shown to effectively reduce morbidity and mortality rates. Arrival at the hospital more than 6 hours after symptom onset and lack of ST-segment elevation are frequently cited as reasons for not administering a thrombolytic drug [13-17]. Studies have documented that treatment is most often delayed because patients do not seek care promptly [18]. The median delay in seeking care after the onset of symptoms of acute myocardial infarction ranges from 2 to 6.4 hours [19]. The median delay to treatment recorded by the National Registry of Myocardial Infarction was 2.2 hours [12]. Although early treatment is potentially beneficial, few patients are treated within the first 60 to 90 minutes. For example, only 3% of patients in the GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries) trial [20], 3% of patients in the TIMI phase II trial [21], and 10.9% of patients in the GISSI (Gruppo Italiano per lo Studio della Streptochinasi nell'Infarto Miocardico) I trial [1] were treated within the first hour after symptom onset. The National Heart Attack Alert Program is a national education program that was launched in 1991 to educate health care providers, health care systems administrators, patients, and the general public about the importance of rapid and appropriate response to symptoms and signs of acute myocardial infarction. The ultimate goal of the program is to reduce morbidity and mortality rates through the early treatment of patients with acute myocardial infarction. The program has directed its initial efforts toward reducing delays to assessment, diagnosis, and treatment in the emergency department. A current objective is to encourage physicians and other health care providers to instruct their high-risk patients to seek immediate and appropriate medical care if they have symptoms that suggest acute myocardial infarction or ischemia. The program plans to begin other public education efforts after further educating health care providers and evaluating the results of community-based research being done by the National Heart, Lung, and Blood Institute. In this paper, which is based on a report of a National Heart Attack Alert Program working group, we describe 1) the rationale for targeting a high-risk group, 2) predictors of patient delay, and 3) recommendations for the education of patients who are at high risk for acute myocardial infarction. Rationale for Targeting a High-Risk Group Education about the symptoms and signs of acute myocardial infarction and the need to seek treatment promptly should ideally be directed to all patients; educating all patients is a long-term goal of the National Heart Attack Alert Program. However, education and counseling should aim to reduce delay for persons who are at high risk for an acute myocardial infarction so that resources can be focused on persons who might benefit most. According to results of health interviews done in 1994, about 8 million persons in the United States have coronary heart disease, about 3 million have cerebrovascular disease, and about 2 million have peripheral vascular disease [22]. Patients with coronary heart disease, clinical atherosclerotic disease of the aorta or peripheral arteries, or clinical cerebrovascular disease are at high risk for subsequent myocardial infarction or death from coronary heart disease [23-25]. About 50% of all myocardial infarctions and at least 70% of deaths from coronary heart disease occur in persons who have had previous manifestations of cardiovascular disease [26, 27]. The risk for subsequent myocardial infarction and death is five- to seven-fold higher in patients who have coronary heart disease or other atherosclerotic disease than in the general population [23]. Predictors of Patient Delay Researchers have identified sociodemographic factors, clinical characteristics, and patient and bystander behaviors that are associated with a long delay in seeking care for acute myocardial infarction. These findings can help clinicians 1) identify patients who are likely to delay seeking treatment and 2) guide strategies for reducing delay. Sociodemographic characteristics, including older age [17, 28-33], female sex [29, 32, 34-37], and being in certain minority groups [18, 35], are associated with a longer delay before care is sought for acute myocardial infarction. Delays also seem to be associated with low socioeconomic status [38, 39], but this finding is not consistent [40]. Several clinical characteristics also affect delay. Severe chest pain is associated with a shorter delay but only if the pain is sudden in onset [34, 37] or is accompanied by hemodynamic instability [28, 32]. Patients who have severe chest pain of gradual onset do not respond more quickly than patients who have pain that is less severe, possibly because these patients adjust to gradually increasing pain [28, 41]. Patients with a history of angina or diabetes are more likely to delay than patients without these conditions [29, 32, 42-44]. A striking finding of all studies is that delays among patients who have already received a diagnosis of coronary heart disease, heart failure, or myocardial infarction are the same as or greater than those among patients who have not previously had a myocardial infarction or diagnosis of coronary heart disease. Physicians, other health care providers, family members, significant others, and friends, in helping patients make decisions about seeking emergency care, can influence the time to therapy. Most patients consult someone, either a layperson or a physician, before calling an ambulance or taking other transportation to the hospital [34, 45]. If a patient telephones a physician or other health care provider who may not be available at the time of the call, delay is substantially increased [34, 44-47]. Patients report to the emergency department more quickly if they consult a friend, coworker, or stranger than if they consult a family member or significant other [34, 48]. In managed care settings, requiring patients to contact their primary care physician or an authorization service before proceeding to the emergency department may contribute to delay. However, delays associated with managed care have not been systematically compared with those associated with fee-for-service. The National Heart Attack Alert Program is working with managed care organizations to develop standards of care that minimize any potential negative effects of preauthorization regulations. Recommendations for the Education of Patients at High Risk for Acute Myocardial Infarction Physicians and other health care providers who are preparing to educate their high-risk patients will need to decide whom to educate, what to tell them, and how to present the message in the most effective manner. All instructions should be entered in patient records so that other members of the health care team can reinforce these instructions during subsequent visits. Whom To Educate Providers should focus their educational efforts on patients who are known to have cardiovascular disease; they should give special attention to women, elderly patients, and patients of low socioeconomic status. Patients with a known history of coronary heart disease who present to the emergency department with chest pain and are discharged from the emergency department have a subsequent rate of death from cardiovascular disease similar to that of patients who are discharged after hospitalization for angina or myocardial infarction [49]. Therefore, providers of emergency care should recommend that such patients see their personal physician soon after the episode. What To Tell High-Risk Patients The message that providers must convey to their patients includes three essential components: provision of information, discussion of emotional issues, and discussion of social factors. Patients should be informed about the typical symptoms of acute myocardial infarction and the actions that should be taken if the symptoms occur. Although the presentation of acute myocardial infarction can be atypical [50, 51], most patients present with chest pain or discomfort, pain or heaviness in the left arm, shortness of breath, or a sense of dread [52]. Analyses of 1027 patients who presented with a myocardial infarction and a history of angina or previous myocardial infarction showed that most patients had chest pain that may have radiated to the arm, neck, or jaw (Table 1). More women than men presented with symptoms of congestive heart failure; nausea; and, to a lesser extent, dyspnea (King County, Washington. Unpublished data). Ta