Three Years Experience ComparingThe Fast Track System and Patient Education on ST-Segment Elevation Myocardial Infarction in Phrae Hospital

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1 Three Years Experience ComparingThe Fast Track System and Patient Education on ST-Segment Elevation Myocardial Infarction in Phrae Hospital Cardiovascular Unit, Department of Medicine, Phrae Hospital, Phrae Thailand. Abstract Objective: To study and compare the epidemiology, management and outcome of patients with ST-segment elevation Myocardial Infarction (STEMI) before and after the development of a fast track system and patient education campaign in Phrae hospital over 3 years. Methods: This was a cross--sectional study of patients with STEMI who were admitted to Phrae Hospital from 1 August 2004 to 30 September 2007, excluding August September 2005 which was used for systems and educational preparation. Patients were classified into 3 groups : before, 1 st and 2 nd year after the fast track system. The epidemiology, management and outcome of patients were compared. Results: There were 278 cases of STEMI admitted to Phrae hospital during the study period. Of these patients, the mean age was 64.9 ± 11.4 years old. Over half of these patients (57.2%) were 65 years old, 44.2% were women and 83.7% had at least one risk factor. Thrombolytic therapy was used in 60.4% of cases; 14.3% received it within 30 minutes of admission, and 33.3% within 3 hours of the onset of symptoms. There was a trend toward decreasing the door to needle time and symptom onset to admission times in patients in the 2 nd and 3 rd group. Thrombolytic therapy was used in the 2 nd group less than the 1 st and 3 rd group. The patients who received beta-blockers and angiotensin converting enzyme inhibitors (ACEI) or angiotensin II receptor blockers (ARB) were found significantly more in the first group than the second or third group.the overall in-hospital mortality was 22.7% and the 31.6% mortality for the second group was significantly higher than the 15.0% for the first group. Factors associated with mortality were age 75 years, cardiogenic shock, ventricular arrhythmia, post-cardiac arrest, complete heart block, initial systolic blood pressure < 100 mmhg and suboptimal important drug usage. Conclusions: Although door to needle time and symptom onset to admission time had a trend to be shortened, there was still a high rate of both in-hospital mortality and complications. These findings suggest that adhering to medical prescription guidelines, cardiopulmonary resuscitation training and referral systems for patients with failed reperfusion should be performed in parallel with a fast track system and patient education campaign. Key words: ST-elevated myocardial infarction, Fast track system, Patient education campaign Thai Heart J 2008; 21 : E-Journal : Introduction Acute myocardial infarction is the most common cause of death in most western industrialized countries (1-3). There have been several studies published concerning acute myocardial infarction in the Thai population (4-5). Mortality in patients with ST-segment elevation myocardial Correspondence: Cardiovascular Unit, Department of Medicine, Phrae Hospital, Phrae Thailand. E mail: mhongknk@phraehospital.go.th infarction (STEMI) has declined substantially in the developed countries over the past 20 years (6), but mortality in Thai patients was higher than reports from Western countries (4-5, 7). Timely reperfusion of the infarct-related coronary artery using fibrinolysis or percutaneous coronary intervention (PCI) is crucial to optimal STEMI treatment. These benefits are greatest when reperfusion is given at the earliest opportunity after symptom onset. In non-pci-capable hospitals, the hospital door-to-needle times should be within 30 minutes for patients in whom thrombolysis is indicated. In PCI-capable hospitals, the hospital door-to-balloon time should be within 90 minutes (8). There have been several studies published

2 Three Years Experience ComparingThe Fast Track System and Patient Education on ST-Segment Elevation Myocardial Infarction in Phrae Hospital concerning the fast track system of care to optimize timeliness of reperfusion therapy for STEMI (9-11). Although door to needle time was shortened by fast track systems, many deaths from STEMI before hospital arrival were still found. The impact of patient education campaigns for the reduction the treatment delay have been reported in several studies (12-14). In Phrae hospital, thrombolysis is only one choice of reperfusion therapy, and in hospitalmortality was 15% higher than western countries (4, 7). The purpose of this article was to study and compare the epidemiology, management and outcome of patients with STEMI before and after the development of a fast track system and a patient education campaign in Phrae hospital over a 3 year period. Methods Operational Definition ST-segment elevated myocardial infarction (STEMI): New or presumed new left bundle branch block (LBBB) or ST-segment elevation at the J point in 2 or more contiguous leads with the cutoff points greater than or equal to 0.2 mv in leads V 1, V 2, or V 3, or greater than or equal to 0.1 mv in other leads and presence of one or both of the following 2 criteria 1) a clinical history of ischemictype chest discomfort > 20 minutes, 2) a rise of CK-MB 25 ng/ml or troponin T 0.1 ng/ml. Diabetes mellitus (DM): history of DM, regardless of duration of disease, need for antidiabetic agents, or fasting blood sugar > 126 mg/dl. Hypertension (HT): HT as documented by 1) History of HT diagnosed and treated with medication, diet, and/or exercise 2) BP>140 mmhg systolic or >90 mmhg diastolic on at least 2 occasions 3) Current use of antihypertensive pharmacological therapy Dyslipidemia: history of dyslipidemia diagnosed and/or treated by a physician. National Cholesterol Education Program criteria include documentation of the following 1) Total cholesterol >200 mg/dl or 2) Low-density lipoprotein (LDL) > 130 mg/dl or 3) High-density lipoprotein (HDL) < 40 mg/dl Smoking: cigarettes within 1 year of admission. Fast track system: included the following - A 12-lead ECG was performed within 10 minutes after emergency room arrival for all patients with chest discomfort or other symptoms suggestive of acute coronary syndrome (ACS). - Emergency room nurses were allowed to administer 300 mg of aspirin (chewed) to patients with suspected ACS unless contraindicated or already taken by another referral-hospital. - If STEMI was diagnosed, a reperfusion checklist for the evaluation of the patient with STEMI was applied by the emergency room physician. An internist was called for the evaluation and decision making use of Streptokinase in the emergency room. - If the initial ECG was not diagnostic of STEMI but the patient remained symptomatic, serial ECGs in the ward were performed to detect the potential development of ST elevation. If ST elevation was detected, Streptokinase was given at the earliest opportunity by the staff internist. - All patients with suspected ACS were labeled FAST TRACK on the OPD card and in the standing orders and were the first priority patient for ward or coronary care unit (CCU) admittance. - For all patients with a FAST TRACK label, a portable chest X-ray was performed in the ward or CCU. Patient education campaign: included the following - Annual WORLD HEART DAY campaign in September. - Those high risk patients with known DM, HT, Dyslipidemia, previous ACS or stable coronary artery disease were registered by the Phrae cardiac care team for the Chom Rom Ruk Hua Jai Phrae club. - Members of the Chom Rom Ruk Hua Jai club had meetings in Phrae hospital three times a year to encourage early recognition of ischemic symptoms and improve self care of their underlying disease. - Letters that contained knowledge about heart attacks, diabetic care, hypertensive care and any new knowledge for the preventeion of heart attacks were sent to members every month. Study Patients This was a cross--sectional study of 278 patients with STEMI who were admitted into Phrae hospital from 1 August 2004 to 30 September 2007, excluding August

3 September 2005, which was used for systems and and patient education preparation. Patients were classified into 3 groups by each year of the study. - First group were patients with STEMI between 1 August 2004 to 31 July These patients in the first group were before the development of the fast track system and patient education campaign. - Second group were patients with STEMI between 1 October 2005 to 30 September Third group were patients with STEMI between 1 October 2006 to 30 September The patients in the second and third groups were patients after the development of the fast track system, and were during the patient education campaign. The epidemiology, management and outcome of patients with STEMI in the 2 nd and 3 rd groups were compared to the 1st group. Statistical Analysis Continuous variables were expressed as mean ± SD or median where appropriate. Discrete variables were expressed as a percentage. Differences in the distribution of selected characteristics between patient groups were examined using the Chi-square test for categorical variables. Differences in continuous variables between study groups were analyzed using either analysis of variance or t tests. A p-value of less than 0.05 was considered as statistically significant. All statistical data were analyzed by the SPSS program for windows version Results 278 patients with STEMI were enrolled from 1 August 2004 to 30 September The baseline characteristics and risk factors for these patients are listed in Table 1 Ṫhe mean age was 64.9 ± 11.4 years and 123 (44.2%) were women. More than half the patients (57.2%) were 65 years old. The patients admitted to the 1 st group were significantly younger than the 2 nd and 3 rd groups. Most patients (83.7%) had at least one risk factor; 158 (56.8%) had hypertension and 76 (27.3%) had diabetes. A history of coronary artery disease was more prevalent among patients within the 1 st group than the 2 nd or 3 rd group. The referral-patients admitted to the 1 st group were significantly less than those for the 2 nd and 3 rd groups. There was a trend towards decreasing time for symptom onset to hospital arrival for patients in the 2 nd and 3 rd groups. 170 (61.2%) patients with STEMI had anterior wall infarction with the first group having significantly more of these patients than the 3 rd group. The pharmacologic treatment of patients is listed in Table 2. A thrombolytic agent was used in 60.4% of the patients with STEMI. Thrombolytic therapy was used less in the 2 nd group than the 1 st or 3 rd groups. Aspirin was used in 95.3% of patients. 42.1% of patients received a beta-blocker whereas 61.2% of patients received an angiotensin converting enzyme inhibitor (ACEI) or an angiotensin II receptor blocker (ARB), and 52.5% of patients received a statin. The patients who received a betablocker and ACEI or ARB were found significantly more in the 1st group than the 2nd or 3rd groups. There was a trend toward a decreasing number of patients receiving aspirin and a statin for the 2 nd and 3 rd groups. The overall median door to needle time for patients who received thrombolysis was 59.5 minutes and there was a trend toward decreasing door to needle time and symptom onset to treatment times for patients in the 2 nd and 3 rd groups (Table 2.). The thrombolytic therapy was initiated within 30 minutes in 14.3 % of the cases and was initiated within 3 hours after symptoms in 33.3% of the cases (Table 3). Hospital mortality overall was 22.7% for these patients, whereas it was significantly higher for patients in the second group (31.6%) compared to patients in the1 st group (15.0%). The other outcomes are listed in Table 4. Except for congestive heart failure patients in the 2 nd group suffered from more complications than patients in the 1 st group. The overall mean patient length of hospital stay was 5.90 days. It was 4.99 days for patients in the 2 nd group which was less than the 6.51 days for patients in the 1 st group. Except for the 2 nd group more than 70% of patients improved and were discharged. The characteristics, risk factors and associated complications of the fatal cases are listed in Table 5. Most of the fatal cases were more elderly and had a significantly higher number of life-threatening complications such as cardiogenic shock, ventricular tachycardia/ventricular fibrillation (VT/VF), complete heart block or low initial systolic blood pressure than the non-fatal cases. Important Drugs (aspirin, beta-blockers, ACEI or ARB and statins)

4 Three Years Experience ComparingThe Fast Track System and Patient Education on ST-Segment Elevation Myocardial Infarction in Phrae Hospital Table 1. Baseline characteristics of Patients 1 st year Gr 2 nd year 3 rd year Gr Total N = 100 GrN = 98 N = 80 N = 278 Mean age [y] 61.4 ± ± ± ± 11.4 Age class (%) < Male (%) Risk factor Diabetes (%) Hypertension (%) Dyslipidemia (%) Smoking* (%) Hx of CAD (%) Number of risk factors** (%) Referral patients (%) Time to admission# Median (IQ); min ( ) ( ) ( ) ( ) Diagnostic (%) Anterior wall STEMI Inferior wall STEMI Other wall STEMI Statistical significant between 1 st vs 2 nd, Statistical significant between 1 st vs 3 rd *Current smoker or history of smoking < 1 year; **Risk factors = diabetes, hypertension, dyslipidemia and smoking; # From symptom onset to hospital arrival; STEMI = STelevation myocardial infarction; CAD = coronary artery disease. were significantly used less in fatal cases than non-fatal cases, but thrombolytic therapy was not a statistically significant factor. The use of inotropic drugs was used more in fatal cases than non-fatal cases. Median door to needle time was 61 (IQ = ) minutes in fatal cases which was longer than the 55 (IQ = ) minutes in non-fatal cases. However, there was no significant difference (P = 0.056) between these times. Fatal cases had significantly shorter hospital stays than nonfatal cases. Discussion Our data provides information about the treatment of acute ST-segment elevation myocardial infarction in a primary care hospital with a rural population that had one cardiologist, one nephrologist and five

5 Table 2. Pharmacologic Treatments* During Hospital Stay and at Discharge 1 st year Gr 2 nd year Gr 3 rd year Gr Total N = 100 N = 98 N = 80 N = 278 Streptokinase(%) Enoxaparin(%) Neither streptokinase & enoxaparin (%) Aspirin (%) B-blockers (%) ACEI or ARB (%) Statins (%) Nitrates (%) IV. Inotropic drug (%) Door to needle time** median (IQ); min ( ) ( ) ( ) ( ) Pain to treatment time** median (IQ); min ( ) ( ) ( ) ( ) *Some patients received > 1 treatment.**only patients with thrombolytic therapy. # from symptom onset to thrombolytic therapy. Statistical significant between 1 st vs 2 nd, Statistical significant between 1 st vs 3 rd ACEI = angiotensin-converting enzyme inhibitor, ARB = Angiotensin II receptor blockage Table 3. Golden period in patients with thrombolytic therapy 1 st year Gr 2 nd year Gr 3 rd year Gr Total N = 60 N = 54 N = 54 N = 168 Door to Needle time (%) 30 minutes minutes minutes minutes > 180 minutes Symptom to thrombolytic time (%) 3.00 hours hours hours > hours

6 Three Years Experience ComparingThe Fast Track System and Patient Education on ST-Segment Elevation Myocardial Infarction in Phrae Hospital Table 4. Hospital Outcomes 1 st year Gr 2 nd year Gr 3 rd year Gr Total N = 100 N = 98 N = 80 N = 278 Death Congestive heart failure Cardiogenic shock VT/VF, Post-cardiac arrest Complete heart block Major bleeding* Hospital stay (mean+/-sd;day) 6.51 ± ± ± ± 5.32 Improved & survive until discharge Not improved & reject treatment Refer to tertiary care hospital VT/VF = ventricular tachycardia/ventricular fibrillation *Major bleeding: intracerebral hemorrhage and Gastrointestinal bleeding Statistical significant between 1 st vs 2 nd, Statistical significant between 1 st vs 3 rd internists, with no fibrin-specific thrombolytic agents, no invasive strategies for revascularization, no intra-aortic balloon pump and only had a two bed coronary care unit. The management of STEMI has been well defined and summarized in guidelines (8). Moreover, there have been several studies published concerning new treatments for STEMI (15-17). However, the earliest reperfusion of the infarct-related coronary artery using fibrinolysis or PCI is central to optimal STEMI treatment. The effectiveness of a fast track system to shortened door to needle time has been demonstrated in previous reports (9-11). However, in our study, we cannot prove that the fast track system is effective. Although door to needle time was shortened by the fast track systems in the 2 nd year group, the in hospitalmortality was higher than the 1 st year group. The goal for patients with STEMI is to achieve a door to needle time within 30 minutes and fibrinolysis is generally preferred in the case of early presentation within 3 hours from symptom onset and delay in invasive strategy (8). In our study, streptokinase was the only thrombolytic agent of choice and was used in sixty percent of patients. The referral patients as well as time delay may be the cause of the absence of thrombolytic therapy seen in our patients. However, 31.8% of the cases arrived within 12 hours and did not receive thrombolytic therapy. Moreover, patients with ambiguous indications for thrombolysis, for example an unusual history or equivocal ECG, or with relative contraindications to thrombolysis, may be reasons why no thrombolytic therapy was received. Notwithstanding the above reasons,the experience of the emergency room physician and staff internist as well as the cardiologist s available time for patients with suspected ACS may be a cause of the absence of received thrombolytic therapy as well. The benefits of a cardiology nurse specialist, who has wide ranging coronary care experience and, can diagnose STEMI and initiate thrombolysis was reported to reduce door to needle time (18). Thus, If a cardiology nurse specialist services the emergency room patients can receive thrombolysis and door to needle times may be improved. Although door to needle time was the shortest in the 2 nd group percentages of patients receiving Streptokinase, aspirin, ACEI or ARB, beta-blockers and statins was not optimal in this group. Moreover, this group also had the highest mortality among the three groups. The reduction of use of thrombolytic agents and other important drugs may be central to hospital outcomes. Our results suggest that adhering to medical prescription guidelines, which improves the outcome of STEMI, should be encouraged.

7 Table 5. Character of Fatal outcomes Factor (%) Non-fatal Fatal p Value N = 215 N = 63 Age (mean+/-sd,years) 63.8 ± ± * Age 75 yr * Female Risk factor - Diabetes Hypertension Dyslipidemia * - Smoking Refer cases Anterior wall STEMI Complication - Congestive heart failure Cardiogenic shock <0.0001* - VT/VF, Post-cardiac arrest <0.0001* - heart block * - Initial SBP<100 mmhg * Treatment - streptokinase** Aspirin <0.0001* - B-blocker * - ACEI or ARB <0.0001* - Statin <0.0001* - Nitrate <0.0001* - IV inotropic drugs <0.0001* Time to admission# 180 ( ) 163 (60-300) Door to needle time#** 61 ( ) 55 ( ) Hospital stay (mean+/-sd; day) 6.69 ± ± 4.68 <0.0001* *Statistical significant, ** Only patients with thrombolytic, # median (IQ); minute From this study, there was high in-hospital mortality and cardiogenic shock which is similar to Thai ACS registry but were higher than GRACE registry. The patients with cardiogenic shock in our study, which usually require an intraaortic balloon pump and invasive strategies for revascularization, was high (23.7%). However, only 5% of patients were referred to a PCI-capable hospital. The benefits of a referral protocol for primary PCI or rescue PCI has been reported in western countries (11, 19). Our results suggest that improving a referral-protocol or PCIcapable hospital-network, which may improve the outcome of STEMI in Phrae hospital, should be developed. There was a high rate of arrhythmic complications, which was an acute complication within hours of symptom onset. Hospital stay in fatal cases was shorter than nonfatal cases. Cardiopulmonary resuscitation training should be performed every year, which should improve complications of arrhythmia and mortality.

8 Three Years Experience ComparingThe Fast Track System and Patient Education on ST-Segment Elevation Myocardial Infarction in Phrae Hospital Study Limitations The present observational study was not intended to compare the outcome of different fast track systems or patient education. STEMI diagnoses were not strictly validated. Some patients may not have been enrolled in our fast track system. Forty percent of the 2 nd and 3 rd groups were referral-patients which did not receive an education campaign. The reason that some patients did not receive thrombolysis was not identified. Conclusion The results of this study provide additional data concerning the fast track system and the patient education campaign in a rural population. Although door to needle time and symptom onset to admission time was shortened there still was a high rate of both in-hospital mortality and complications. These findings suggest that adhering to medical prescription guidelines, cardiopulmonary resuscitation training and referral systems of patients with failed reperfusion should be performed in parallel to the fast track system and patient education campaign. References 1. Roger WJ, Bowlby LJ, Chandra NC, et al. United States (1990 to 1993) Observations from the National Registry of Myocardial Infarction. Circulation 1994; 90: Steg PG, Robert J, Goldberg, et al. Baseline Characteristics, Management Practices and In-Hospital Outcomes of Patients Hospital with Acute Coronary Syndromes in the Global Registry of Acute Coronary Events (GRACE). Am J Cardiol 2002; 90: Rosamond W, Flegal K, Friday G, et al. Heart disease and stroke statistics-2007 update: a report from the American Heart Association Statistics Committee and Stroke Statistic Subcommittee. Circulation 2007; 115: e Maraprasertsak M. Acute coronary syndrome in Phrae Hospital. Thai Heart J 2006; 19: Thai acute coronary syndrome registry (Data 1 August 2002 to 31 October 2005). The Heart Association of Thailand under The Royal Patronage. 6. Boersma E, Mercado N, Poldermans D, Gardien M, Vos J, Simoons ML. Acute myocardial infarction. Lancet 2003; 361: Carruthers KF, Dabbous OH, et al. Comtemporary management of Acute coronary syndromes: does the practice match the evidence? The global registry of acute coronary events (GRACE). Heart 2005; 91: Antman EM, Anbe DT, Armstrong PW, et al.acc/aha Guidelines for the Management of Patients with ST-Elevation Myocardial Infarction Executive Summary. A Report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1999 Guidelines for the Management of Patients with Acute Myocardial Infarction). J Am Coll Cardiol 2004; 44: Alastair CH, Hugh CM, Colin ER, Keith AA. Effect of fast track admission for acute myocardial infarction on delay to thrombolysis. BMJ 1992; 304: Worachotekamjorn K, Suithichaiyakul T, Srimahachota S, Bhuddari W, Udayachalerm W. Effect of fast-track system on door-to-balloon time and door-to-needle time for acute myocardial infarction patients. Thai Heart J 2002; 15: Henry HT, Charanjit SH, Bernard JG, et al. Regional system of care to optimize Timeliness of Reperfusion Therapy for STelevation Myocardial infarction. (The Mayo Clinic STEMI protocol). Circulation 2007; 116: Rowley JM, Hill JD, Hampton JR, Mitchell JRA. Early reporting of myocardial infarction: impact of and experiment in patient education. BMJ 1982; 284: McGinn AP, Rosamond WD, Goff Dc Jr, Tayler HA, Miles JS, Chambless L. Trends in prehospital delay time and use of emergency medical services for acute myocardial infarction: experience in 4 US communities from Am Heart J 2005; 150: Luepker RV, Raczynski JM, Osganian S, el al. Effect of a community intervention on patient delay and emergency medical service use in acute coronary heart disease: the Rapid Early Action for Coronary Treatment (REACT) Trial. JAMA 2000; 284: Sabatine MS, Cannon CP, Gibson CM, et al. Addition of clopidogrel to aspirin and fibrinolytic therapy for myocardial infarction with ST-segment elevation. N Engl J Med 2005; 352: Antman EM, Morrow DA, McCabe CH. the ExTRACT-TIMI 25 Investigators. Enoxaparin versus Unfractionated Heparin with fibrinolysis for ST-elevation myocardial infarction. N Engl J Med 2006; 354: Yusuf S, Granger CB, Budaj A, et al. Effects of Fondaparinux on mortality and reinfarction in patients with acute ST-segment elevation myocardial nfarction (The OASIS-6 Randomized Trial). JAMA 2006; 295: Heath SM, Bain RJI, Andrews A, Chida S, Kitchen SI, Walters MI. Nurse initiated thrombolysis in the accident and emergency department: safe, accurate, and faster than fast track. Emerg Med J 2003; 20: Dalby M, Bouzamondo A, Lechat P, Montalescot G. Transfer for Primary angioplasty Versus Immediate Thrombolysis in Acute Myocardial Infarction, A Meta-analysis. Circulation 2003; 108:

9 การศ กษา ผ ป วยกล ามเน อห วใจตายเฉ ยบพล นชน ด ST-segment elevation ท เข าร บ การร กษาในโรงพยาบาลแพร ในช วงเวลา 3 ป : ภายหล งม การพ ฒนาช องทางด วนสำหร บ ผ ป วย และการให ความร เก ยวก บโรคแก ผ ป วย มงคล มะระประเสร ฐศ กด, พบ. หน วยห วใจและหลอดเล อด, กล มงานอาย รกรรม, โรงพยาบาลแพร จ งหว ดแพร บทค ดย อ จ ดประสงค : เพ อศ กษาระบาดว ทยา ว ธ การร กษา และผลการร กษาในผ ป วยกล ามเน อห วใจตายเฉ ยบพล นชน ด ST-segment elevation ท เข าร บการร กษาในโรงพยาบาลแพร ในช วง 3 ป และเปร ยบเท ยบระบาดว ทยา ว ธ การร กษา และผลการร กษา ใน ช วงก อน และภายหล งม การพ ฒนาช องทางด วนสำหร บผ ป วย และม การให ความร เก ยวก บโรคแก ผ ป วย ว ธ การศ กษา: โดยรวบรวมข อม ลผ ป วยกล ามเน อห วใจตายเฉ ยบพล นชน ด ST-segment elevation ท เข าร บการร กษาในโรง พยาบาลแพร ในช วง 3 ป ต งแต 1 ส งหาคม 2547 ถ ง 30 ก นยายน 2550 ยกเว นช วงเด อน ส งหาคม ก นยายน 2548 ซ งเป นช วง เตร ยมระบบช องทางด วนสำหร บผ ป วย และได แบ งผ ป วยเป น 3 กล ม และนำข อม ลของผ ป วย ในกล มท 2 และ 3 ซ งเป นกล ม ผ ป วยภายหล งม ช องทางด วน และได ร บความร เก ยวก บโรคกล ามเน อห วใจตายเฉ ยบพล น เปร ยบเท ยบก บกล มท 1 ซ งเป นกล ม ผ ป วยก อนม ช องทางด วน และได ร บความร ผลการศ กษา: ม ผ ป วยกล ามเน อห วใจตายเฉ ยบพล นชน ด ST-segment elevationในการศ กษาท งหมด 278 คน. อาย เฉล ย 64.9 ป. 57.2% ของผ ป วยม อาย มากกว า 65 ป, 44.2% เป นเพศหญ ง และ 83.7% ม ป จจ ยเส ยงต อการเก ดโรค. ม การใช ยาละลายล ม เล อด 60.4% ในผ ป วยท งหมด, 14.3% ม การให ยาละลายล มเล อดภายใน 30 นาท หล งจากร บไว ในโรงพยาบาล, 33.3% สามารถ ให ยาละลายล มเล อดได ภายใน 3 ช วโมงหล งจากท ผ ป วยม อาการ. พบว าระยะเวลาในการให ยาละลาย ล มเล อดภายหล งจากร บ ผ ป วยไว ในโรงพยาบาล และระยะเวลาจากผ ป วยม อาการจนมาโรงพยาบาล จะม แนวโน มลดลง ในผ ป วยกล มท 2 และ 3. อ ตรา การให ยาละลายล มเล อดในผ ป วยกล มท 2 ม น อยกว า ผ ป วยกล มท 1 และ 3. ม การใช ยา ต านเบต า (B-blocker) และยาต าน angiotensin II ( ACEI or ARB) ในกล มท 1 มากกว ากล มท 2 และ 3 อย างม น ยสำค ญ ทางสถ ต. อ ตราตายในโรงพยาบาล 22.7%, ม อ ตราการตายในกล มผ ป วยกล มท 2 เท าก บ 31.6% ซ งมากกว า อ ตราการตาย ในกล มท 1 ซ งเท าก บ 15.0%อย างม น ย สำค ญทางสถ ต. ป จจ ยท ส มพ นธ ก บอ ตราการตายค อ ผ ป วยอาย มากกว า 75 ป, ภาวะช อคจากโรคห วใจ (cardiogenic shock), ภาวะห วใจเต นผ ดจ งหวะชน ด ventricular arrhythmia, ภาวะภายหล ง ห วใจหย ดเต น, complete heart block, การม ความด น โลห ตซ สโตล ค (systolic BP) แรกร บ น อยกว า 100 ม ลล เมตรปรอทและ การให ยาท จำเป นต อการร กษาน อยเก นไป. สร ป: แม ว าระยะเวลาในการให ยาละลายล มเล อดภายหล งจากร บผ ป วยไว ในโรงพยาบาล และระยะเวลาจากผ ป วย ม อาการ จนมาโรงพยาบาลจะม แนวโน มลดลง แต ย งม อ ตราการตายและอ ตราการเก ดภาวะแทรกซ อนท ส ง. ผลการศ กษาน สน บสน น ว า โรงพยาบาลแพร ควรเน นให ม การใช ยาท เป นประโยชน แก ผ ป วยให มากข น, ควรม การฝ กอบรม การก ช ว ตผ ป วย (cardiopulmonary resuscitation) และควรม ระบบส งต อ ผ ป วยท ไม สามารถเป ดหลอดเล อดห วใจได ด วยยาละลาย ล มเล อดให ม ประส ทธ ภาพ ซ งควรทำไปพร อมๆก บการม ระบบช องทางด วนสำหร บผ ป วย และการให ความร แก ผ ป วย