Factors Influencing Pre-hospital Patient Delay in Patients with Acute Myocardial Infarction

La Xie，Su-Fang Huang，You-Zhen Hu

Emergency Department，Tongji Hospital of Tongji Medical College，Huazhong Science and Technology University，Hubei，Wuhan 430030，China

Review article

Factors Influencing Pre-hospital Patient Delay in Patients with Acute Myocardial Infarction

La Xie，Su-Fang Huang*，You-Zhen Hu

Emergency Department，Tongji Hospital of Tongji Medical College，Huazhong Science and Technology University，Hubei，Wuhan 430030，China

A R T I C L E I N F O

Article history：

10 February 2015

Accepted 11 April 2015

Published 20 June 2015

Acute myocardial infarction

Pre-hospital delay

Factors

Acute myocardial infarction（AMI）is a dangerous disease with a high mortality rate. For AMI patients，the outcome of the patients depends on time to beginning of effective treatment in addition to other factors such as severity of disease and involved vessels etc.The key is whether reperfusion therapy is started early enough after the onset of symptoms，and the benefit of reperfusion therapy depends on the time，too.The delay of AMI treatment is divided into pre-hospital delay and in-hospital delay.In-hospital delay，Door-to-Balloon Time，has been well controlled. Pre-hospital delay，accounting for 75%of the total delay time，is the most important factor affecting AMI treatment.Patient delay（PD）time for AMI patients is summarised in this study.

?2015 Shanxi Medical Periodical Press.Production and hosting by Elsevier B.V.This is an open access article.under the cc BY-NC-ND license（http://creativecommons.org/license/by-nc-nd/4.0/）.

1.Introduction

Acute myocardial infarction is a dangerous disease with a high mortality rate.For AMI patients，t he fate ofthe heart and the patient's life depends on time to beginning of effective treatment in addition to other factors such as severity of disease and involved vessels etc.The key factor is whether reperfusion therapy is started timely after the onset of symptoms，and the benefit of reperfusion therapy depends on the time.1Guidelines emphasise the need to minimise reperfusion delay time for patients with acute myocardial infarction.2Delay before the initiation of reperfusion therapy for AMI can be divided intotwo distinct time periods：pre-hospital delay and in-hospital delay.Pre-hospital delay is the time from onset of symptoms to arrival to the hospital.In-hospital delay，also known as door-to-treatment，is defined as the time from arriving to the hospital to the initiation of reperfusion therapy.Pre-hospital delay can be divided into two time periods：patient delay（PD）time and transportation delay（TD）time.Patient delay is time from the onset of symptoms to making the initial decision to seek for professional healthcare facility，and transportation delay is the time from making the initial decision to seek professional healthcare facility to arrival at the hospital.3Prehospital delay is mainly caused by the patient's own decisions and is much longer than in-hospital delay and the time needed to decide on initiating reperfusion therapy.4Regardless of how to shorten in-hospital delay，if the pre-hospital delay is not reduced，then reperfusion therapy cannot achieve the best results.5However，patient delay time，which accounts for 75%of the total prehospital delay time，6has not changed in the past 10 years.7，8Thus，reducing patient delay time is very important for AMI patients.9To analyse the literature on pre-hospital delay，the CNKI，Wanfang，PubMed and Yizhi databases were searched.PD for AMI patients is summarised in this study.

2.Essential information

2.1.Age

Increased age has been associated with a longer prehospital delay in many studies.10-18This may be explained by the following several reasons：（1）The elderly have reduced physiological function and a lower ability to perceive pain.（2）Older patients are more likely to have atypical symptoms compared with younger patients and have more comorbidities，which may result in a delay for seeking medical care19，20and limit their correct recognition of warning symptoms.21，22（3）The elderly have insufficient perceptions of AMI and do not want to trouble the family with their symptoms，and thus，the actual rescue time will be longer.23.However，other researchers did not find a statistically significant result for the effect of age on delay.5，24，25

2.2.Gender

Female gender was a significant variable in predicting delay.Female patients with AMI had a prolonged decision-makingprocesscomparedwith males.5，12，15，26，27There are several potential explanations for this finding：（1）The incidence of AMI for males corresponds to that of older females.28-31Older female patients often have other chronic diseases，which is a disadvantage for them in terms of their medical care and treatment.26，32（2）Females are more likely to have atypical symptoms compared with males，28，22，33-37making females less apt to interpret their symptoms，such as being related to a heart attack.38-41（3）Females appear to have a belief that AMI is a“male”disease and that they are associated with a lower risk of AMI.40，41In contrast，other studies have not found significant gender differences.14，20，24，29，42

Age and gender can affect each other.The elderly have a large gender difference for pre-hospital delay，and older females delay significantly longer than males；however，the reason may be because the incidence of heart disease of women corresponds to that of men who are 10 years younger.20，43

2.3.Marital status

Single，widowed or divorced patients have a longer delay time for seeking care compared to patients who are married.14，28，44The reason may be that there is no one to consult immediately.Among males，married or common law status was strongly associated with earlier health-seeking behaviour in the setting of acute myocardial infarction.Among females，married or common law status was not associated with a similar reduction in delay before seeking medical attention.45However，a study reported that marital status is not associated with prehospital delay.42

2.4.Previous history

Patients with a history of diabetes，22，46-48hypertension22or angina pectoris49have been found to delay longer than those without these conditions.However，several studies15have reported that patients with prior AMI delay less，but many others did not find any association between delay and history of AMI.5，9，50

2.5.Health insurance

Patients with health insurance have a shorter delay than those without insurance.51-53

2.6.Economic level

Several studies have reported that the economic level is associated with pre-hospital delay，54，55e.g.，patients with a higher income have an earlier presentation for care.Conversely，other studies have found that economic level has no effect on pre-hospital delay time.56

2.7.Education level

Low-education levels were a significant determinant of longer pre-hospital delay.11，12，44，55，57

2.8.Living condition

Living alone was an independent predictor of longer delay time，4，28but another study reported that living condition was not associated with pre-hospital delay.14

2.9.Race

Minorities who were more likely to have specific cultural health beliefs and perceptions related to medical behaviour were associated with a significantly longer delay.16，58

3.Symptoms

3.1.Types

The classic symptoms of an AMI include chest pain，but some investigators found that 20.0%-33.3%of patients with AMI did not experience central chest pain at all.5，28，59Some atypical symptoms，such as weakness，shortness of breath，anxiety，abdominal discomfort or sweating can occur when experiencing an AMI60and were associated with a substantially longer pre-hospital delay.29，57

3.2.Intensity

Increased symptom intensity and having fast onset symptoms（symptoms that develop rapidly）were associated with a shorter pre-hospital delay.5，24，25，61

3.3.Duration

Having continuous symptoms predicted a short prehospital delay5，37，38and having intermittent symptoms predicted a longer delay.14，42

4.Contextual factors

4.1.Time when the symptoms occur

Having symptom onset at night was associated with a longer pre-hospital delay.62There may be no other person available to help at night，and thus，the patients did not want to trouble others and planned to seek healthcare during the daytime.Another reason may be that it is difficult to find a way of transportation and a person to help at night.46

4.2.Location where symptoms occur

Being home12，24or in a public place24when symptoms began resulted in a longer delay to treatment. However，one study found no significant differences between early and late responders with regard to location of where the symptoms began.63

4.3.Whether there is a bystander when the symptoms occur

Patients who experienced symptoms alone had longer delays compared to patients who had company.25Having someone present when the symptoms occur can not only reduce fear but also lead to a responsible decision regarding treatment and thus a shorter pre-hospital delay.64

5.Cognitive and affective factors

5.1.Cognitive factors

5.1.1.Symptom identification

The patient's correct identification of symptoms was an important predictor for delay time.65Patients who ex-perienced symptoms that are different from those expected to be associated with AMI delayed care，and patients who correctly recognised the symptoms of AMI experienced less delay.14，41，42

5.1.2.Symptom attribution

5.1.3.The perception of severity and susceptibility

Patients who thought that their symptoms were heart related sought treatment faster than individuals who did not relate their symptoms to a heart problem.24，25，56，66

Lackofperceivedseriousnessofsymptoms5，14，42，55，67and lack of perceived susceptibility to heart disease41，68were associated with a longer delay.

5.1.4.Perceived control symptoms

Patients who perceived being able to cope with or control symptoms were associated with an increased delay.24，67

5.1.5.Knowledge related to AMI

Being able to recognize the importance of a short delay when experiencing an AMI was associated with a significant delay when deciding to seek treatment.25

5.2.Affective factors

5.2.1.Fear

Fear of the consequences can significantly shorten the patients'decision time.25

5.2.2.Denial of AMI

Denial is a self-defence mechanism toward illness because people tend to reject ideas that are associated with potentially unpleasant experiences or feelings.69Thus，denial is a common reaction among patients with signs of AMI64，70and can cause considerable pre-hospital delay.47，71，72

5.2.3.Fear of troubling others

Longer pre-hospital delay was perpetuated by the fear of troubling other family members or other persons.14，73，74

6.Behavioural factors

6.1.（Calling）Consulting others

There are two scenarios.First，calling or visiting the primary care provider（PCP），usually in foreign countries，was associated with a substantially long pre-hospital delay.5The potential reason is that the consultation process itself is very time-consuming.However，telling members，friends or colleagues may play a crucial role in helping the victims to overcome their fear of the disease or denial about their symptoms，which occurs more commonly in China，and the patients experienced a shorter delay.5，9，29，75，76

6.2.Self-treatment

Self-treatment with drugs or rest can lead to a long pre-hospital delay.77

6.3.Transportation

This factor is mainly divided into calling for ambulance transport and self-transport.Patients choosing ambulance transportation reduced their pre-hospital delay time.5，24However，patients choosing self-transport delayed treatment due to the lack of timely treatment.46The most frequent reason for not choosing an ambulance was that the patient did not perceive the symptoms to be sufficiently serious to merit a dramatic action，such as calling the EMS.78The second most common reason for not choosing ambulance transport was that the patients believed that self-transport would be faster.79，80The last reason was that the patient became aware of the fact that ambulances are only a mode of transport and did not understand the capability of the paramedics.

7.Conclusions

Factors influencing pre-hospital patient delay for patients with acute myocardial infarction vary，and many research results are also contradictory regarding factors such as age，gender，and previous myocardial infarc-tion.In addition，there are some interplay factors，such as between age and gender，gender and marital status，and cognitive and affective factors on the behavioural reaction.Nevertheless，predicting factors that could lead to delay using investigations of different populations could provide a reference to help professional medical care providers to develop some strategies to reduce the delay time.47Well designed future studies are needed to better understand the influencing factors related to patient delay and to resolve the controversy surrounding these associations.In addition，targeted intervention measures have been undertaken according to these factors with the goal of reducing the extent of pre-hospital delay in patients with signs and symptoms of AMI.

Conflicts of interest

All contributing authors declare no conflicts of interest.

References

1.Wang LJ，Liu Y，Liu XF，et al.Investigating the factors of affecting the treatment delay of AMI patients.Nurs Pract Res. 2012；9：8-10［in Chinese］.

2.Guidelines on myocardial revascularization.The task force on myocardial revascularization of the European society of Cardiology（ESC）and the European association for Cardio-thoracic surgery（EACTS）.Eur Heart J.2010；31：2501.

3.Cui G，Xu WL，Li BH.Researching pre-hospital delay time distribution and influence factor of ST segment elevation acute myocardial infarction patients.Contemporary Medicine.2013；19：30-31［in Chinese］.

4.Perkins-Porras L，Whitehead DI，Strike PC，et al.Pre-hospital delay in patients with acute coronary syndrome：factors associated with pre-hospital delay patient decision time and hometo-hospital delay.Eur J Cardiovasc Nurs.2009；8：26-33.

5.Johansson I，Str?mberg A，Swahn E.Factors related to delay times in patients with suspected acute myocardial infarction，Heart Lung.2004；33：291-300.

6.Hirvonen TP，Halinen MO，Kala RA，Olkinuora JT.Delays in thrombolytic therapy for acute myocardial infarction in Finland.Results of a national thrombolytic therapy delay study. Finnish Hospitals'Thrombolysis Survey Group.Eur Heart J. 1998；19：885-92.

7.Goldberg RJ，Spencer FA，F(xiàn)ox KAA，et al.Prehospital delay in patients with acute coronary syndromes（from the global registry of acute Coronary Events［GRACE］）.Am J Cardiol. 2009；103：598-603.

8.Spencer FA，Montalescot G，F(xiàn)ox KAA，et al.Delay to reperfusion in patients with acute myocardial infarction presenting to acute care hospitals：an international perspective.Eur Heart J. 2010；31：1328-1336.

9.Henriksson C，Larsson M，Arnetz J，et al.Knowledge and attitudes toward seeking medical care for AMI-symptoms.International Journal of Cardiology.2011；147：224-227.

10.Berger AK，Radford MI，Krumholz HM.Factors associated with delay in reperfusion therapy in elderly patients with acute myocardial infarction：analysis of the cooperative cardiovamular project.Am Heart J.2000；139：985-992.

11.Ganova-Iolovska M，Kalinov K，Geraedts M.Quality of care of patients with acute myocardial infarction in Bulgaria：a cross-sectional study.BMC Health Serv Res.2009；9：15.

12.Sail I，Acar Z，Ozer O，et al.Factors associated with prolonged prehospital delay in patients with acute myocardial infarction.Turk Kardiyol Dem Ars.2008；36：156-162.

13.Saezynski JS，Yarzebski J，Lessard D，et al.Trends in prehospital delay in patients with acute myocardial infarction（from the Worcester Heart Attack Study）.Am J Cardiol. 2008；102：1409-1594.

14.McKinley S，Moser DK，Dracup K.Treatment-seeking behaviour for acute myocardial infarction symptoms in North America and Australia.Heart Lung.2000；29：237-247.

15.Sheifer SE，Rathore SS，Gersh BJ，et al.Time to presentation with acute myocardial infarction in the elderly：associations with race，sex，and socioeconomic characteristics.Circulation.2000；102：1651-1656.

16.Goldberg R，Goff D，Cooper L，et al.Age and sex differences in presentation of symptoms among patients with acute coronary disease：the REACT trial.Rapid early action for coronary treatment.Coron Artery Dis.2000；11：399-407.

17.Ting HH，Bradley EH，Wang Y.et al.Factors associated with longer time from symptom onset to hospital presentation for patients with ST-elevation myocardial infarction.Arch Intern Med.2008；168：959-968.

18.Nguyen HL，Saczynski JS，Gore JM，Goldberg RJ.Age and sex differences in duration of prehospital delay in patients with acute myocardial infarction：a systematic review.Circ Cardiovasc Qual Outcomes.2010；3：82-92.

19.Goldberg RJ，Steg PG，Sadiq I，et al.Extent of，and factors associated with，delay to hospital presentation in patients with acute coronary disease（the GRACE registry）.Am J Cardiol. 2002；89：791-796.

20.Isaksson RM，Holmgren L，Lundblad D，Brulin C，Eliasson M.Time trends in symptoms and prehospital delay time in women vs.men with myocardial infarction over a 15-year period.The Northern Sweden MONICA Study.Eur J Cardiovasc Nurs.2008；7：152-158.

21.Ladwig KH，Meisinger C，Hymer H，et al.Sex and age specific time patterns and long term time trends of pre-hospital delay of patients presenting with acute ST-segment elevation myocardial infarction.Int J Cardiol.2011；152：350-355.

22.Fokkema ML，Wieringa WG，Horst IC，Boersma E，Zijlstra F，de Smet BJ.Quantitative analysis of the impact of total is-chemic time on myocardial perfusion and clinical outcome in patients with ST-elevation myocardial infarction.Am J Cardiol.2011；108：1536-1541.

23.Liang H，Liu Y，Zhao YM，et al.Efficacy of different treatments for Elderly AMI patients，Chin J Heart Dis.2010；12：319-322［in Chinese］.

24.Lesneski L.Factors influencing treatment delay for patients with acute myocardial infarction.Appl Nurs Res.2010；23：185-190.

25.Herlitz J，Thuresson M，Svensson L，et al.Factors of importance for patients'decision time in acute coronary syndrome. Int J Cardiol.2010；141：236-242.

26.Waller CG.Undertanding prehospital delay behavior in acute myocardial infarction in women.Crit Pathw Cardiol.2006；5：228-234.

27.Heer T，Schiele R，Schneider S，et al.Gender differences in acute myocardial infarction in the era of reperfusion（the MITRA registry）.Am J Cardiol.2002；89：511-517.

28.Banks AD，Dracup K.Are there gender differences in the reasons why African Americans delay in seeking medical help for symptoms of an acute myocardial infarction？Ethn Dis. 2007；17：221-227.

29.Lovlien M，Schei B，Hole T.Prehospital delay，contributing aspects and responses to symptoms among Norwegian women and men with first time acute myocardial infarction.Eur J Cardiovasc Nurs.2007；6：308-313.

30.Carrabba N，Santoro GM，Balzi D，et al.In-hospital management and outcome in women with acute myocardial infarction（data from the AMI-Florence Registry）.Am J Cardiol. 2004；94：1118-1123.

31.King KB，McGuire MA.Symptom presentation and time to seek care in women and men with acute myocardial infarction.Heart Lung.2007；36：235-243.

32.Rosenfeld AG.State of the heart：building science to improve women's cardiovascular health.Am J Crit Care.2006；15：556-567.

33.Chen W，Woods SL，Puntillo KA.Gender differences in symptoms associated with acute myocardial infarction：a review of the research.Heart Lung.2005；34：240-247.

34.Patel H，Rosengren A，Ekman I.Symptoms in acute coronary syndromes：does sex make a difference？Am Heart J. 2004；148：27-33.

35.Song L，Yan HB，Yang JG，SunYH，Hu DY.Impact of patients'symptom interpretation on care-seeking behaviours of patients with acute myocardial infarction.Chin Med J（Engl）.2010；123：1840-1845.

36.Albarran JW，Clarke BA，Crawford J.'It was not chest pain really，I can't explain it！'An exploratory study on the nature of symptoms experienced by women during their myocardial infarction.J Clin Nurs.2007；16：1292-1301.

37.Canto JG，Goldberg RJ，Hand MM，et al.Symptom presentation of women with acute coronary syndromes：myth vs reality.Arch Intern Med.2007，167：2405-2413.

38.Schoenberg NE，Peters JC，Drew EM.Unravelling the mysteries of timing：women's perceptions about time to treatment for cardiac symptoms.Soc Sci Med.2003；56：271-284.

39.Rosenfeld AG，Lindauer A，Darney BG.Understanding treatment-seeking delay in women with acute myocardial infarction：descriptions of decision-making patterns.Am J Crit Care.2005；14：285-293.

40.Herning M，Hansen PR，Bygbjerg B，Lindhardt T.Women's experiences and behaviour at onset of symptoms of ST segment elevation acute myocardial infarction.Eur J Cardiovasc Nurs.2011；10：241-247.

41.MacInnes JD.The illness perceptions of women following symptoms of acute myocardial infarction：a self-regulatory approach.Eur J Cardiovasc Nurs.2006；5：280-288.

42.Noureddine S，Adra M，Arevian M，et al.Delay in seeking health care for acute coronary syndromes in a Lebanese sample.J Transcult Nurs.2006；17：341-348.

43.Maynard C，Weaver WD，Lambrew C，Bowlby LJ，Rogers WJ，Rubison RM.Factors influencing the time to administration of thrombolytic therapy with recombinant tissue plasminogen activator（data from the National registry of myocardial Infarction）.Participants in the National registry of myocardial Infarction.Am J Cardiol.1995；76：548-552.

44.Fournier S，Muller O，Ludman AJ，Lauriers N，Eeckhout E. Influence of socioeconomic factors on delays，management and outcome amongst patients with acute myocardial infarction undergoing primary percutaneous coronary intervention. Swiss Med Wkly.2013，143：w13817.

45.Atzema CL，Austin PC，Huynh T，et al.Effect of marriage on duration of chest pain associated with acute myocardial infarction before seeking care.CMAJ.2011；183：1482-1491.

46.Xie ZH，Zeng SY，Huang WF.Analysis the factors about before treatment delay time of acute myocardial infarction patients.Chin Pharm Guide.2012；10：460-461［in Chinese］.

47.Khraim FM，Carey MG.Predictors of pre-hospital delay among patients with acute myocardial infarction.Patient Educ Counsel.2009；75：155-161.

48.DeVon HA，Penckofer S，Larimer K.Midwest nursing research society sage best paper award：the association of diabetes and older age with the absence of chest pain during acute coronary syndromes.West J Nurs Res.2008；30：130-144.

49.Yan HB，Li S，Yang J，Sun Y，Hu D.The association between pre-infarction angina and care-seeking behaviours and its effects on early reperfusion rates for acute myocardial infarction.Int J Cardiol.2009；135：86-92［in Chinese］.

50.Fukuoka Y，Dracup K，Moser DK，et al.Is severity of chest pain a cue for women and men to recognize acute myocardial infarction symptoms as cardiac in origin？Prog Cardiovasc Nurs.2007；22：132-7.

51.Liu YJ，Liang Y，Zhu J.Analysis the factors of pre-hospital delay with acute myocardial infarction patients.Hebei Pharmaceutical.2010；32：975-976［in Chinese］.

52.Parikh SV，Jacobi JA，Chu E，et al.Treatment delay in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction：a key process analysis of patient and program factors.Am Heart J.2008；155：290-297.

53.Smolderen KG，Spertus JA，Nallamothu BK，et al.Health care insurance，financial concerns，and delays to hospital presentation in acute myocardial infarction.JAMA.2010；303：1392-1400.

54.Foraker RE，Rose KM，McGinn AP，et al.Neighbourhood income.Health insurance，and prehospital delay for myocardial infarction：the atherosclerosis risk in communities study. Arch Intern Med.2008；168：l874-1879.

55.Okhravi M.Causes for pre-hospital and in-hospital delays in acute myocardial infarction at tehran teaching hospitals.Aust Emerg Nurs J.2002；5：21-26.

56.Dianati M，Mosavi GA，Hajibagheri A，Alavi NM.The prehospital delay in seeking treatment in patients with acute myocardial infarction referring to a central hospital in Kashan，Iran.Indian J Med Sci.2010；64：448-454.

57.Khan MS，Jafary FH，F(xiàn)aruqui AM，et al.High prevalence of lack of knowledge of symptoms of acute myocardial infarction in Pakistan and its contribution to delayed presentation to the hospital.BMC Public Health.2007；7：284.

58.Klingler D，Green-Weir R，Nerenz D，et al.Perceptions of chest pain differ by race.Am Heart J.2002；144：51-59.

59.Thygesen K，Alpert JS，Jaffe AS，et al.Third universal definition of myocardial infarction.Circulation.2012；126：2020-2035.

60.Lefler L.The advanced practice nurse's role regarding women's delay in seeking treatment with myocardial infarction.J Am Acad Nurse Pract.2002；14：449-456.

61.Noureddine S，Arevian M，Adra M，Puzantian H.Response to signs and symptoms of acute coronary syndrome：differences between Lebanese men and women.Am J Crit Care. 2008；17：26-35.

62.Guo JC，Hua Q，Liu DX.Factors related to patient delay time in patients with acute myocardial infarction ST segment elevation and essential hypertension.Am J Hypertens.2005；18：219-220［in Chinese］.

63.Wu Y，Zhang Y，Li YQ，Hong BL，Huang CX.Factors associated with the extent of care-seeking delay for patients with acute myocardial infarction in Beijing.Chin Med J（Engl）. 2004；117：1772-1777.

64.Pattenden J，Watt I，Robert J，et al.Decision making process in people with symptoms of acute myocardial infarction：qualitative study.BMJ.2002；324：1006-1010.

65.Ryan CJ，Zerwic JJ.Perceptions of symptoms of myocardial infarction related to health care seeking behaviors in the elderly.J Cardiovasc Nurs.2003；18：184-196.

66.Fox-Wasylyshyn SM，El-Masri M，Artinian NT.Testing a model of delayed care-seeking for acute myocardial infarction.Clin Nurs Res.2010；19：38-54.

67.Morgan DM.Effect of incongruence of acute myocardial infarction symptoms on the decision to seek treatment in a rural population.J Cardiovasc Nurs.2005；20：365-371.

68.Rosenfeld AG.Treatment-seeking delay among women with acute myocardial infarction：decision trajectories and their predictors.Nurs Res.2004；53：225-236.

69.Stenstrom U，Nilsson AK，Stridh C，et al.Denial in patients with a first-time myocardial infarction：relations to pre-hospital delay and attendance to a cardiac rehabilitation programme.Eur J Cardiovasc Prev Rehabil.2005；12：568-571.

70.Rosenfeld AG，Gilkeson J.Meaning of illness for women with coronary heart disease.Heart Lung.2000；29：105-112.

71.Buckley T，McKinley S，Gallagher R，et al.The effect of education and counselling on knowledge，attitudes and beliefs about responses to acute myocardial infarction symptoms.Eur J Cardiovasc Nurs.2006；6：105-111.

72.Daisy LP，Philip W，Steptoe SA.Causal beliefs，cardiac denial and pre-hospital delays following the onset of acute coronary syndromes.J Behav Med.2008；31：498-505.

73.O'Gara PT，Kushner FG，Ascheim DD，et al.2013 ACCF/ AHA guideline for the management of ST-elevation myocardial infarction：g report of the American College of Cardiology Foundation/American heart association task force on practice guidelines.Circulation.2013；127：e369-e373.

74.Nymark C，Mattiasson AC，Henriksson P，et al.The turning point：from self-regulative illness behaviour to care-seeking in patients with an acute myocardial infarction.J Clin Nurs. 2009；18：3340-3365.

75.Thuresson M，Jarlov MB，Lindahl B，et al.Thoughts，actions，and factors associated with prehospital delay in patients with acute coronary syndrome.Heart Lung.2007；36：398-409.

76.Henriksson C，Lindahl B，Larsson M.Patients'and relatives'thoughts and actions during and after symptom presentation for an acute myocardial infarction.Eur J Cardiovasc Nurs.2007；6：280-286.

77.Leslie WS，Urie A，Hooper J，et al.Delay in calling for help during myocardial infarction：reasons for the delay and subsequent pattern of accessing care.Heart.2000；84：137-141.

78.Lozzi L，Carstensen S，Rasmussen H，et al.Why do acute myocardial infarction patients not call an ambulance？an interview with patients presenting to hospital with acute myocardial infarction symptorns.Intern Med J.2005；35：668-671.

79.Kerr D，Holden D，Smith J，et al.Predictors of ambulance use in patients with acute myocardial infarction in Australia. Emerg Med J.2006；23：948-952.

80.Thuresson M，Jarlov MB，Lindahl B，et al.Factors that influence the use of ambulance in acute eoronarysyndrome.Am Heart J.2008；156：170-176.

21 December 2014

in revised form

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E-mail address：sfhuang2008@163.com（S.-F.Huang）.

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2095-7718/?2015 Shanxi Medical Periodical Press.Production and hosting by Elsevier B.V.This is an open access article.under the cc BY-NC-ND license（http：//creativecommons.org/license/by-nc-nd/4.0/）.