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ACC/AHA PRACTICE GUIDELINES

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)³

Writing Committee Members, Elliott M. Antman, MD, FACC, FAHA, Chair, Daniel T. Anbe, MD, FACC, FAHA, Paul Wayne Armstrong, MD, FACC, FAHA, Eric R. Bates, MD, FACC, FAHA, Lee A. Green, MD, MPH, Mary Hand, MSPH, RN, FAHA, Judith S. Hochman, MD, FACC, FAHA, Harlan M. Krumholz, MD, FACC, FAHA, Frederick G. Kushner, MD, FACC, FAHA, Gervasio A. Lamas, MD, FACC, Charles J. Mullany, MB, MS, FACC, Joseph P. Ornato, MD, FACC, FAHA, David L. Pearle, MD, FACC, FAHA, Michael A. Sloan, MD, FACC, Sidney C. Smith, Jr, MD, FACC, FAHA Task Force Members, Elliott M. Antman, MD, FACC, FAHA, Chair, Sidney C. Smith, Jr, MD, FACC, FAHA, Vice-chair, Joseph S. Alpert, MD, FACC, FAHA^*, Jeffrey L. Anderson, MD, FACC, FAHA, David P. Faxon, MD, FACC, FAHA, Valentin Fuster, MD, PhD, FACC, FAHA, Raymond J. Gibbons, MD, FACC, FAHA^*, Gabriel Gregoratos, MD, FACC, FAHA^*, Jonathan L. Halperin, MD, FACC, FAHA, Loren F. Hiratzka, MD, FACC, FAHA, Sharon Ann Hunt, MD, FACC, FAHA, Alice K. Jacobs, MD, FACC, FAHA, Joseph P. Ornato, MD, FACC, FAHA

	Table of contents

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

II. Pathology 673

A. Epidemiology 673

III. Management Before STEMI 673

A. Identification of Patients at Risk of STEMI 673

B. Patient Education for Early Recognition and Response to STEMI 673

IV. Onset of STEMI 675

A. Out-of-Hospital Cardiac Arrest 675

V. Prehospital Issues 675

A. Emergency Medical Services Systems 675

B. Prehospital Chest Pain Evaluation and Treatment 675

C. Prehospital Fibrinolysis 675

D. Prehospital Destination Protocols 677

VI. Initial Recognition and Management in the Emergency Department 677

A. Optimal Strategies for Emergency Department Triage 677

B. Initial Patient Evaluation 677

1. History 678

2. Physical Examination 678

3. Electrocardiogram 678

4. Laboratory Examinations 678

5. Biomarkers of Cardiac Damage 678

a. Bedside Testing for Serum Cardiac Biomarkers 679

6. Imaging 679

C. Management 679

1. Routine Measures 679

a. Oxygen 679

b. Nitroglycerin 679

c. Analgesia 679

d. Aspirin 680

e. Beta-Blockers 680

f. Reperfusion 680

• General Concepts 680

• Selection of Reperfusion Strategy 680

• Pharmacological Reperfusion 682

• Percutaneous Coronary Intervention 684

• Acute Surgical Reperfusion 688

• Patients With STEMI Not Receiving Reperfusion 688

• Assessment of Reperfusion 688

• Ancillary Therapy 688

• Other Pharmacological Measures 690

VII. Hospital Management 691

A. Location 691

1. Coronary Care Unit 691

2. Stepdown Unit 691

B. Early, General Measures 692

1. Level of Activity 692

2. Diet 692

3. Patient Education in the Hospital Setting 692

4. Analgesia/Anxiolytics 692

C. Risk Stratification During Early Hospital Course 692

D. Medication Assessment 693

1. Beta-Blockers 693

2. Nitroglycerin 693

3. Inhibition of the Renin-Angiotensin-Aldosterone System 693

4. Antiplatelets 694

5. Antithrombotics 694

6. Oxygen 694

E. Estimation of Infarct Size 694

1. Electrocardiographic Techniques 694

2. Cardiac Biomarker Methods 694

3. Radionuclide Imaging 694

4. Echocardiography 694

5. Magnetic Resonance Imaging 694

F. Hemodynamic Disturbances 694

1. Hemodynamic Assessment 694

2. Hypotension 695

3. Low-Output State 695

4. Pulmonary Congestion 695

5. Cardiogenic Shock 696

6. Right Ventricular Infarction 697

7. Mechanical Causes of Heart Failure/Low-Output Syndrome 697

a. Diagnosis 697

b. Mitral Valve Regurgitation 697

c. Ventricular Septal Rupture After STEMI 698

d. Left Ventricular Free-Wall Rupture 698

e. Left Ventricular Aneurysm 698

f. Mechanical Support of the Failing Heart 698

• Intra-Aortic Balloon Counterpulsation 698

G. Arrhythmias After STEMI 698

1. Ventricular Arrhythmias 698

a. Ventricular Fibrillation 698

b. Ventricular Tachycardia 699

c. Ventricular Premature Beats 699

d. Accelerated Idioventricular Rhythms and Accelerated Junctional Rhythms 699

e. ICD Implantation in Patients After STEMI 700

2. Supraventricular Arrhythmias/Atrial Fibrillation 700

3. Bradyarrhythmias 701

a. Acute Treatment of Conduction Disturbances and Bradyarrhythmias 701

• Ventricular Asystole 701

b. Use of Permanent Pacemakers 701

• Permanent Pacing for Bradycardia or Conduction Blocks Associated With STEMI 701

• Sinus Node Dysfunction After STEMI 701

• Pacing Mode Selection in Patients With STEMI 701

H. Recurrent Chest Pain After STEMI 701

1. Pericarditis 701

2. Recurrent Ischemia/Infarction 703

I. Other Complications 704

1. Ischemic Stroke 704

2. DVT and Pulmonary Embolism 704

J. Coronary Artery Bypass Graft Surgery After STEMI 704

1. Timing of Surgery 704

2. Arterial Grafting 704

3. CABG for Recurrent Ischemia After STEMI 704

4. Elective CABG Surgery After STEMI in Patients With Angina 705

5. CABG Surgery After STEMI and Antiplatelet Agents 705

K. Convalescence, Discharge, and Post-Myocardial Infarction Care 705

1. Risk Stratification at Hospital Discharge 705

a. Role of Exercise Testing 705

b. Role of Echocardiography 705

c. Exercise Myocardial Perfusion Imaging 707

d. Left Ventricular Function 707

e. Invasive Evaluation 707

f. Assessment of Ventricular Arrhythmias 707

L. Secondary Prevention 708

1. Patient Education Before Discharge 708

2. Lipid Management 708

3. Weight Management 708

4. Smoking Cessation 710

5. Antiplatelet Therapy 710

6. Inhibition of Renin-Angiotensin-Aldosterone-System 710

7. Beta-Blockers 711

8. Blood Pressure Control 711

9. Diabetes Management 712

10. Hormone Therapy 712

11. Warfarin Therapy 712

12. Physical Activity 712

13. Antioxidants 712

VIII. Long-Term Management 713

A. Psychosocial Impact of STEMI 713

B. Cardiac Rehabilitation 713

C. Follow-Up Visit With Medical Provider 713

References 714

	I. Introduction

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

 
Although considerable improvement has occurred in the process of care for patients with ST-elevation myocardial infarction (STEMI), room for improvement exists (1–3). The purpose of the present guideline is to focus on the numerous advances in the diagnosis and management of patients with STEMI since 1999. This is reflected in the changed name of the guideline: "ACC/AHA Guidelines for the Management of Patients With ST-Elevation Myocardial Infarction." The final recommendations for indications for a diagnostic procedure, a particular therapy, or an intervention in patients with STEMI summarize both clinical evidence and expert opinion (Table 1). To provide clinicians with a set of recommendations that can easily be translated into the practice of caring for patients with STEMI, this guideline is organized around the chronology of the interface between the patient and the clinician. The full guideline is available at http://www.acc.org/clinical/guidelines/stemi/index.htm.

	II. Pathology

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

	III. Management before STEMI

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

 
A. Identification of patients at risk of STEMI.   Class I

1. Primary care providers should evaluate the presence and status of control of major risk factors for coronary heart disease (CHD) for all patients at regular intervals (approximately every 3 to 5 years). (Level of Evidence: C)
   
2. Ten-year risk (National Cholesterol Education Program [NCEP] global risk) of developing symptomatic CHD should be calculated for all patients who have 2 or more major risk factors to assess the need for primary prevention strategies (14) (Level of Evidence: B).
   
3. Patients with established CHD should be identified for secondary prevention, and patients with a CHD risk equivalent (eg, diabetes mellitus, chronic kidney disease, or 10-year risk greater than 20% as calculated by Framingham equations) should receive equally intensive risk factor intervention as those with clinically apparent CHD. (Level of Evidence: A)
   

B. Patient education for early recognition and response to STEMI.   Class I

1. Patients with symptoms of STEMI (chest discomfort with or without radiation to the arms[s], back, neck, jaw, or epigastrium; shortness of breath; weakness; diaphoresis; nausea; lightheadedness) should be transported to the hospital by ambulance rather than by friends or relatives. (Level of Evidence: B)
   
2. Healthcare providers should actively address the following issues regarding STEMI with patients and their families:
   1. The patient's heart attack risk (Level of Evidence: C)
      
   2. How to recognize symptoms of STEMI (Level of Evidence: C)
      
   3. The advisability of calling 9-1-1 if symptoms are unimproved or worsening after 5 minutes, despite feelings of uncertainty about the symptoms and fear of potential embarrassment (Level of Evidence: C)
      
   4. A plan for appropriate recognition and response to a potential acute cardiac event that includes the phone number to access emergency medical services (EMS), generally 9-1-1 (15). (Level of Evidence: C)
      
   
   
3. Healthcare providers should instruct patients for whom nitroglycerin has been prescribed previously to take ONE nitroglycerin dose sublingually in response to chest discomfort/pain. If chest discomfort/pain is unimproved or worsening 5 minutes after 1 sublingual nitroglycerin dose has been taken, it is recommended that the patient or family member/friend call 9-1-1 immediately to access EMS. (Level of Evidence: C)
   

Morbidity and mortality due to STEMI can be reduced significantly if patients and bystanders recognize symptoms early, activate the EMS system, and thereby shorten the time to definitive treatment. Patients with possible symptoms of STEMI should be transported to the hospital by ambulance rather than by friends or relatives because there is a significant association between arrival at the emergency department (ED) by ambulance and early reperfusion therapy (16–19). Although the traditional recommendation is for patients to take 1 nitroglycerin dose sublingually, 5 minutes apart, for up to 3 doses before calling for emergency evaluation, this recommendation has been modified by the writing committee to encourage earlier contacting of EMS by patients with symptoms suggestive of STEMI (20,21).

	IV. Onset of STEMI

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

 
A. Out-of-hospital cardiac arrest.   Class I

1. All communities should create and maintain a strong "Chain of Survival" for out-of-hospital cardiac arrest that includes early access (recognition of the problem and activation of the EMS system by a bystander), early cardiopulmonary resuscitation (CPR), early defibrillation for patients who need it, and early advanced cardiac life support (ACLS). (Level of Evidence: C)
   
2. Family members of patients experiencing STEMI should be advised to take CPR training and familiarize themselves with the use of an automated external defibrillator (AED). In addition, they should be referred to a CPR training program that has a social support component for family members of post-STEMI patients. (Level of Evidence: B)
   

The links in the chain include early access (recognition of the problem and activation of the EMS system by a bystander), early CPR, early defibrillation for patients who need it, and early ACLS.

	V. Prehospital issues

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

 
A. Emergency medical services systems.   Class I

1. 1.All EMS first responders who respond to patients with chest pain and/or suspected cardiac arrest should be trained and equipped to provide early defibrillation. (Level of Evidence: A)
   
2. 2.All public safety first responders who respond to patients with chest pain and/or suspected cardiac arrest should be trained and equipped to provide early defibrillation with AEDs. (Provision of early defibrillation with AEDs by nonpublic safety first responders is a promising new strategy, but further study is needed to determine its safety and efficacy.) (Level of Evidence: B)
   
3. 3.Dispatchers staffing 9-1-1 center emergency medical calls should have medical training, should use nationally developed and maintained protocols, and should have a quality-improvement system in place to ensure compliance with protocols. (Level of Evidence: C)
   

Early access to EMS is promoted by a 9-1-1 system currently available to more than 90% of the US population. To minimize time to treatment, particularly for cardiopulmonary arrest, many communities allow volunteer and/or paid firefighters and other first-aid providers to function as first responders, providing CPR and, increasingly, early defibrillation using automated external defibrillators (AEDs) until emergency medical technicians and paramedics arrive. Most cities and larger suburban areas provide EMS ambulance services with providers from the fire department, a private ambulance company, and/or volunteers.

B. Prehospital chest pain evaluation and treatment.   Class I

1. Prehospital EMS providers should administer 162 to 325 mg of aspirin (chewed) to chest pain patients suspected of having STEMI unless contraindicated or already taken by patient. Although some trials have used enteric-coated aspirin for initial dosing, more rapid buccal absorption occurs with non–enteric-coated formulations. (Level of Evidence: C)
   

Class IIa

1. It is reasonable for all 9-1-1 dispatchers to advise patients without a history of aspirin allergy who have symptoms of STEMI to chew aspirin (162 to 325 mg) while awaiting arrival of prehospital EMS providers. Although some trials have used enteric-coated aspirin for initial dosing, more rapid buccal absorption occurs with non–enteric-coated formulations. (Level of Evidence: C)
   
2. It is reasonable that all ACLS providers perform and evaluate 12-lead electrocardiograms (ECGs) routinely on chest pain patients suspected of STEMI. (Level of Evidence: B)
   
3. If the ECG shows evidence of STEMI, it is reasonable that prehospital ACLS providers review a reperfusion "checklist" and relay the ECG and checklist findings to a predetermined medical control facility and/or receiving hospital. (Level of Evidence: C)
   

It is reasonable for physicians to encourage the prehospital administration of aspirin via EMS personnel (ie, EMS dispatchers and providers) in patients with symptoms suggestive of STEMI unless its use is contraindicated (22). For patients who have ECG evidence of STEMI, it is reasonable that paramedics review a reperfusion checklist and relay the ECG and checklist findings to a predetermined medical control facility and/or receiving hospital.

C. Prehospital fibrinolysis.   Class IIa

1. Establishment of a prehospital fibrinolysis protocol is reasonable in 1) settings in which physicians are present in the ambulance or in 2) well-organized EMS systems with full-time paramedics who have 12-lead ECGs in the field with transmission capability, paramedic initial and ongoing training in ECG interpretation and STEMI treatment, online medical command, a medical director with training/experience in STEMI management, and an ongoing continuous quality-improvement program. (Level of Evidence: B)
   

Randomized controlled trials of fibrinolytic therapy have demonstrated the benefit of initiating fibrinolytic therapy as early as possible after onset of ischemic-type chest discomfort (Figure 1) (23–25). It appears reasonable to expect that if fibrinolytic therapy could be started at the time of prehospital evaluation, a greater number of lives could be saved. Prehospital fibrinolysis is reasonable in those settings in which physicians are present in the ambulance or prehospital transport times are more than 60 minutes in high-volume (more than 25,000 runs per year) EMS systems (26). Other considerations for implementing a prehospital fibrinolytic service include the ability to transmit ECGs, paramedic initial and ongoing training in ECG interpretation and myocardial infarction (MI) treatment, online medical command, a medical director with training/experience in management of STEMI, and full-time paramedics (27).

View larger version (30K): [in this window] [in a new window]   Figure 1 Options for transportation of STEMI patients and initial reperfusion treatment. Panel A, : Reperfusion in patients with STEMI can be accomplished by the pharmacological (fibrinolysis) or catheter-based (primary PCI) approaches. Implementation of these strategies varies based on the mode of transportation of the patient and capabilities at the receiving hospital. Transport time to the hospital is variable from case to case, but the goal is to keep total ischemic time within 120 minutes. There are 3 possibilities: (1) If EMS has fibrinolytic capability and the patient qualifies for therapy, prehospital fibrinolysis should be started within 30 minutes of EMS arrival on scene. (2) If EMS is not capable of administering prehospital fibrinolysis and the patient is transported to a non–PCI-capable hospital, the hospital door-to-needle time should be within 30 minutes for patients in whom fibrinolysis is indicated. (3) If EMS is not capable of administering prehospital fibrinolysis and the patient is transported to a PCI-capable hospital, the hospital door-to-balloon time should be within 90 minutes. : It is also appropriate to consider emergency interhospital transfer of the patient to a PCI-capable hospital for mechanical revascularization if (1) there is a contraindication to fibrinolysis; (2) PCI can be initiated promptly. (within 90 minutes after the patient presented to the initial receiving hospital or within 60 minutes compared to when fibrinolysis with a fibrin-specific agent could be initiated at the initial receiving hospital); or (3) fibrinolysis is administered and is unsuccessful (ie, "rescue PCI"). Secondary nonemergency interhospital transfer can be considered for recurrent ischemia. : Patient self-transportation is discouraged. If the patient arrives at a non–PCI-capable hospital, the door-to-needle time should be within 30 minutes. If the patient arrives at a PCI-capable hospital, the door-to-balloon time should be within 90 minutes. The treatment options and time recommendations after first hospital arrival are the same. Panel B, For patients who receive fibrinolysis, noninvasive risk stratification is recommended to identify the need for rescue PCI (failed fibrinolysis) or ischemia-driven PCI. See Sections 6.3.1.6 [EC] .4.5. and 6.3.1.6 [EC] .7. in the full-text guidelines. Regardless of the initial method of reperfusion treatment, all patients should receive late hospital care and secondary prevention of STEMI. EMS indicates Emergency Medical System; PCI, percutaneous coronary intervention; CABG, coronary artery bypass graft surgery; Hosp, hospital; Noninv., Noninvasive. * Golden hour = First 60 minutes; The medical system goal is to facilitate rapid recognition and treatment of patients with STEMI such that door-to-needle (or medical contact–to-needle) time for initiation of fibrinolytic therapy is within 30 minutes or that door-to-balloon (or medical contact–to-balloon) time for PCI is within 90 minutes. These goals should not be understood as ideal times but rather as the longest times that should be considered acceptable for a given system. Systems that are able to achieve even more rapid times for treatment of patients with STEMI should be encouraged. Modified with permission from Armstrong et al. Circulation. 2003;107:2533–7 (25).

1. Patients with STEMI who have cardiogenic shock and are less than 75 years of age should be brought immediately or secondarily transferred to facilities capable of cardiac catheterization and rapid revascularization (percutaneous coronary intervention [PCI] or coronary artery bypass graft surgery [CABG]) if it can be performed within 18 hours of onset of shock. (Level of Evidence: A)
   
2. Patients with STEMI who have contraindications to fibrinolytic therapy should be brought immediately or secondarily transferred promptly (ie, primary-receiving hospital door-to-departure time less than 30 minutes) to facilities capable of cardiac catheterization and rapid revascularization (PCI or CABG). (Level of Evidence: B)
   
3. Every community should have a written protocol that guides EMS system personnel in determining where to take patients with suspected or confirmed STEMI. (Level of Evidence: C)
   

Class IIa

1. It is reasonable that patients with STEMI who have cardiogenic shock and are 75 years of age or older be considered for immediate or prompt secondary transfer to facilities capable of cardiac catheterization and rapid revascularization (PCI or CABG) if it can be performed within 18 hours of onset of shock. (Level of Evidence: B)
   
2. It is reasonable that patients with STEMI who are at especially high risk of dying, including those with severe congestive heart failure (CHF), be considered for immediate or prompt secondary transfer (ie, primary-receiving hospital door-to-departure time less than 30 minutes) to facilities capable of cardiac catheterization and rapid revascularization (PCI or CABG). (Level of Evidence: B)
   

Every community should have a written protocol that guides EMS system personnel in determining where to take patients with suspected or confirmed STEMI. Active involvement of local healthcare providers, particularly cardiologists and emergency physicians, is needed to formulate local EMS destination protocols for these patients. In general, patients with suspected STEMI should be taken to the nearest appropriate hospital. However, patients with STEMI and shock are an exception to this general rule. Whenever possible, STEMI patients less than 75 years of age with shock should be transferred to facilities capable of cardiac catheterization and rapid revascularization (PCI or CABG). On the basis of observations in the SHOCK Trial Registry and other registries, it is reasonable to extend such considerations of transfer to invasive centers for elderly patients with shock (see VII.F.5 and Section 7.6.5 of the full-text guidelines). Patients with STEMI who have contraindications to fibrinolytic therapy should be brought immediately or secondarily transferred promptly (ie, primary-receiving hospital door-to-departure time less than 30 minutes) to facilities capable of cardiac catheterization and rapid revascularization (PCI or CABG).

	VI. Initial recognition and management in the emergency department

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

 
A. Optimal strategies for emergency department triage.   Class I

1. Hospitals should establish multidisciplinary teams (including primary care physicians, emergency medicine physicians, cardiologists, nurses, and laboratorians) to develop guideline-based, institution-specific written protocols for triaging and managing patients who are seen in the prehospital setting or present to the ED with symptoms suggestive of STEMI. (Level of Evidence: B)
   

B. Initial patient evaluation.   Class I

1. The delay from patient contact with the healthcare system (typically, arrival at the ED or contact with paramedics) to initiation of fibrinolytic therapy should be less than 30 minutes. Alternatively, if PCI is chosen, the delay from patient contact with the healthcare system (typically, arrival at the ED or contact with paramedics) to balloon inflation should be less than 90 minutes. (Level of Evidence: B)
   
2. The choice of initial STEMI treatment should be made by the emergency medicine physician on duty based on a predetermined, institution-specific, written protocol that is a collaborative effort of cardiologists (both those involved in coronary care unit management and interventionalists), emergency physicians, primary care physicians, nurses, and other appropriate personnel. For cases in which the initial diagnosis and treatment plan is unclear to the emergency physician or is not covered directly by the agreed-on protocol, immediate cardiology consultation is advisable. (Level of Evidence: C)
   

Regardless of the approach used, all patients presenting to the ED with chest discomfort or other symptoms suggestive of STEMI or unstable angina should be considered high-priority triage cases and should be evaluated and treated based on a predetermined, institution-specific chest pain protocol. The goal for patients with STEMI should be to achieve a door-to-needle time within 30 minutes and a door-to-balloon time within 90 minutes (Figure 1)(25).

1. History
Class I

1. The targeted history of STEMI patients taken in the ED should ascertain whether the patient has had prior episodes of myocardial ischemia such as stable or unstable angina, MI, CABG, or PCI. Evaluation of the patient's complaints should focus on chest discomfort, associated symptoms, sex- and age-related differences in presentation, hypertension, diabetes mellitus, possibility of aortic dissection, risk of bleeding, and clinical cerebrovascular disease (amaurosis fugax, face/limb weakness or clumsiness, face/limb numbness or sensory loss, ataxia, or vertigo). (Level of Evidence: C)
   

2. Physical examination
Class I

1. A physical examination should be performed to aid in the diagnosis and assessment of the extent, location, and presence of complications of STEMI. (Level of Evidence: C)
   
2. A brief, focused, and limited neurological examination to look for evidence of prior stroke or cognitive deficits should be performed on STEMI patients before administration of fibrinolytic therapy. (Level of Evidence: C)
   

A brief physical examination may promote rapid triage, whereas a more detailed physical examination aids in the differential diagnosis and is useful for assessing the extent, location, and presence of complications of STEMI.

3. Electrocardiogram
Class I

1. A 12-lead ECG should be performed and shown to an experienced emergency physician within 10 minutes of ED arrival for all patients with chest discomfort (or anginal equivalent) or other symptoms suggestive of STEMI. (Level of Evidence: C)
   
2. If the initial ECG is not diagnostic of STEMI but the patient remains symptomatic, and there is a high clinical suspicion for STEMI, serial ECGs at 5- to 10-minute intervals or continuous 12-lead ST-segment monitoring should be performed to detect the potential development of ST elevation. (Level of Evidence: C)
   
3. In patients with inferior STEMI, right-sided ECG leads should be obtained to screen for ST elevation suggestive of right ventricular (RV) infarction. (See Section 7.6.6 of the full-text guidelines and the ACC/AHA/ASE 2003 Guideline Update for the Clinical Application of Echocardiography.) (Level of Evidence: B)
   

The 12-lead ECG in the ED is at the center of the therapeutic decision pathway because of the strong evidence that ST-segment elevation identifies patients who benefit from reperfusion therapy (28).

4. Laboratory examinations
Class I

1. Laboratory examinations should be performed as part of the management of STEMI patients but should not delay the implementation of reperfusion therapy. (Level of Evidence: C)
   

In addition to serum cardiac biomarkers for cardiac damage, several routine evaluations have important implications for management of patients with STEMI. Although these studies should be ordered when the patient is first seen, therapeutic decisions should not be delayed until results are obtained because of the crucial role of time to therapy in STEMI.

5. Biomarkers of cardiac damage
Class I

1. Cardiac-specific troponins should be used as the optimum biomarkers for the evaluation of patients with STEMI who have coexistent skeletal muscle injury. (Level of Evidence: C)
   
2. For patients with ST elevation on the 12-lead ECG and symptoms of STEMI, reperfusion therapy should be initiated as soon as possible and is not contingent on a biomarker assay. (Level of Evidence: C)
   

Class IIa

1. Serial biomarker measurements can be useful to provide supportive noninvasive evidence of reperfusion of the infarct artery after fibrinolytic therapy in patients not undergoing angiography within the first 24 hours after fibrinolytic therapy. (Level of Evidence: B)
   

Class III

1. Serial biomarker measurements should not be relied on to diagnose reinfarction within the first 18 hours after the onset of STEMI. (Level of Evidence: C)
   

For patients with ST-segment elevation, the diagnosis of STEMI is secure; initiation of reperfusion therapy should not be delayed to wait for the results of a cardiac biomarker assay (29). Quantitative analysis of cardiac biomarker measurements provides prognostic information and a noninvasive assessment of the likelihood that the patient has undergone successful reperfusion when fibrinolytic therapy is administered.

a. Bedside testing for serum cardiac biomarkers
Class I

1. Although handheld bedside (point-of-care) assays may be used for a qualitative assessment of the presence of an elevated level of a serum cardiac biomarker, subsequent measurements of cardiac biomarker levels should be performed with a quantitative test. (Level of Evidence: B)
   
2. For patients with ST elevation on the 12-lead ECG and symptoms of STEMI, reperfusion therapy should be initiated as soon as possible and is not contingent on a bedside biomarker assay. (Level of Evidence: C)
   

A positive bedside test should be confirmed by a conventional quantitative test. However, reperfusion therapy should not be delayed to wait for the results of a quantitative assay.

6. Imaging.   Class I

1. Patients with STEMI should have a portable chest X-ray, but this should not delay implementation of reperfusion therapy (unless a potential contraindication, such as aortic dissection, is suspected). (Level of Evidence: C)
   
2. Imaging studies such as a high-quality portable chest X-ray, transthoracic and/or transesophageal echocardiography, and a contrast chest computed tomographic scan or a MRI scan should be used to differentiate STEMI from aortic dissection in patients for whom this distinction is initially unclear. (Level of Evidence: B)
   

Class IIa

1. Portable echocardiography is reasonable to clarify the diagnosis of STEMI and allow risk stratification of patients with chest pain on arrival at the ED, especially if the diagnosis of STEMI is confounded by left bundle-branch block (LBBB) or pacing, or there is suspicion of posterior STEMI with anterior ST depressions. (See Section 7.6.7 Mechanical Causes of Heart Failure/Low Output Syndrome of the full-text guidelines.) (Level of Evidence: B)
   

Class III

1. Single-photon emission computed tomography (SPECT) radionuclide imaging should not be performed to diagnose STEMI in patients for whom the diagnosis of STEMI is evident on the ECG. (Level of Evidence: B)
   

	C. Management

Top Table of contents I. Introduction II. Pathology III. Management before STEMI IV. Onset of STEMI V. Prehospital issues VI. Initial recognition and... C. Management Acute surgical reperfusion Patients with STEMI not... Assessment of reperfusion Ancillary therapy Antiplatelets VII. Hospital management B. Early, general measures C. Risk stratification during... D. Medication assessment E. Estimation of infarct... F. Hemodynamic disturbances G. Arrhythmias after STEMI 2. Supraventricular... 3.Bradyarrhythmias a. Acute treatment of... References

 
1. Routine measures.   a. Oxygen
Class I

1. Supplemental oxygen should be administered to patients with arterial oxygen desaturation (SaO₂ less than 90%). (Level of Evidence: B)
   

Class IIa

1. It is reasonable to administer supplemental oxygen to all patients with uncomplicated STEMI during the first 6 hours. (Level of Evidence: C)
   

b. Nitroglycerin
Class I

1. Patients with ongoing ischemic discomfort should receive sublingual nitroglycerin (0.4 mg) every 5 minutes for a total of 3 doses, after which an assessment should be made about the need for intravenous nitroglycerin. (Level of Evidence: C)
   
2. Intravenous nitroglycerin is indicated for relief of ongoing ischemic discomfort, control of hypertension, or management of pulmonary congestion. (Level of Evidence: C)
   

Class III

1. Nitrates should not be administered to patients with systolic blood pressure less than 90 mmHg or greater than or equal to 30 mmHg below baseline, severe bradycardia (less than 50 bpm), tachycardia (more than 100 bpm), or suspected RV infarction. (Level of Evidence: C)
   
2. Nitrates should not be administered to patients who have received a phosphodiesterase inhibitor for erectile dysfunction within the last 24 hours (48 hours for tadalafil). (Level of Evidence: B)
   

Nitroglycerin may be administered to relieve ischemic pain and is clearly indicated as a vasodilator in patients with STEMI associated with left ventricular (LV) failure. Nitrates in all forms should be avoided in patients with initial systolic blood pressures less than 90 mmHg or greater than or equal to 30 mmHg below baseline, in patients with marked bradycardia or tachycardia (30), and in patients with known or suspected RV infarction. In view of their marginal treatment benefits, nitrates should not be used if hypotension limits the administration of beta-blockers, which have more powerful salutary effects.

c. Analgesia
Class I

1. Morphine sulfate (2 to 4 mg IV with increments of 2 to 8 mg IV repeated at 5- to 15-minute intervals) is the analgesic of choice for management of pain associated with STEMI. (Level of Evidence: C)
   

d. Aspirin
Class I

1. Aspirin should be chewed by patients who have not taken aspirin before presentation with STEMI. The initial dose should be 162 mg (Level of Evidence: A) to 325 mg (Level of Evidence: C). Although some trials have used enteric-coated aspirin for initial dosing, more rapid buccal absorption occurs with non–enteric-coated aspirin formulations.
   

In a dose of 162 mg or more, aspirin produces a rapid clinical antithrombotic effect caused by immediate and near-total inhibition of thromboxane A2 production. Aspirin now forms part of the early management of all patients with suspected STEMI and should be given promptly, and certainly within the first 24 hours, at a dose between 162 and 325 mg and continued indefinitely at a daily dose of 75 to 162 mg (31). Although some trials have used enteric-coated aspirin for initial dosing, more rapid buccal absorption occurs with non–enteric-coated formulations (32).

e. Beta-blockers
Class I

1. Oral beta-blocker therapy should be administered promptly to those patients without a contraindication, irrespective of concomitant fibrinolytic therapy or performance of primary PCI. (Level of Evidence: A)
   

Class IIa

1. It is reasonable to administer IV beta-blockers promptly to STEMI patients without contraindications, especially if a tachyarrhythmia or hypertension is present. (Level of Evidence: B)
   

Immediate beta-blocker therapy appears to reduce the magnitude of infarction and incidence of associated complications in subjects not receiving concomitant fibrinolytic therapy, the rate of reinfarction in patients receiving fibrinolytic therapy, and the frequency of life-threatening ventricular tachyarrhythmias.

f. Reperfusion
General concepts
   Class I

1. All STEMI patients should undergo rapid evaluation for reperfusion therapy and have a reperfusion strategy implemented promptly after contact with the medical system. (Level of Evidence: A)
   

Evidence exists that expeditious restoration of flow in the obstructed infarct artery after the onset of symptoms in STEMI patients is a key determinant of short- and long-term outcomes regardless of whether reperfusion is accomplished by fibrinolysis or PCI (33–35). As discussed previously (also see Section 4.1 of the full- text guidelines), efforts should be made to shorten the time from recognition of symptoms by the patient to contact with the medical system. All healthcare providers caring for STEMI patients from the point of entry into the medical system must recognize the need for rapid triage and implementation of care in a fashion analogous to the handling of trauma patients. When considering recommendations for timely reperfusion of STEMI patients, the Writing Committee reviewed data from clinical trials, focusing particular attention on enrollment criteria for selection of patients for randomization, actual times reported in the trial report rather than simply the allowable window specified in the trial protocol, treatment effect of the reperfusion strategy on individual components of a composite primary end point (eg, mortality, recurrent nonfatal infarction), ancillary therapies (eg, antithrombin and antiplatelet agents), and the interface between fibrinolysis and referral for angiography and revascularization. When available, data from registries were also reviewed to assess the generalizability of observations from clinical trials of reperfusion to routine practice. Despite the wealth of reports on reperfusion for STEMI, it is not possible to produce a simple algorithm, given the heterogeneity of patient profiles and availability of resources in various clinical settings at various times of day. This section introduces the recommendations for an aggressive attempt to minimize the time from entry into the medical system to implementation of a reperfusion strategy using the concept of medical system goals. More detailed discussion of these goals and the issues to be considered in selecting the type of reperfusion therapy are discussed in the Selection of Reperfusion Therapy section of VI.C.1.f (Section 6.3.1.6 [EC] .2 of the full-text guidelines), followed by a discussion of available resources.

The medical system goal is to facilitate rapid recognition and treatment of patients with STEMI such that door-to-needle (or medical contact–to-needle) time for initiation of fibrinolytic therapy can be achieved within 30 minutes or that door-to-balloon (or medical contact–to-balloon) time for PCI can be kept under 90 minutes. These goals may not be relevant for the patients with an appropriate reason for delay, such as uncertainty about the diagnosis (particularly for the use of fibrinolytic therapy), need for the evaluation and treatment of other life-threatening conditions (eg, respiratory failure), or delays associated with the patient's informed choice to have more time to consider the decision. In the absence of such types of circumstances, the emphasis is on having a system in place such that when a patient with STEMI presents for medical care, reperfusion therapy is able to be provided as soon as possible within these time periods. Because there is not considered to be a threshold effect for the benefit of shorter times to reperfusion, these goals should not be understood as "ideal" times but the longest times that should be considered acceptable. Systems that are able to achieve even more rapid times for patients should be encouraged. Also, this goal should not be perceived as an average performance standard but a goal of an early treatment system that every hospital should seek for every appropriate patient.

Selection of reperfusion strategy
Several issues should be considered in selecting the type of reperfusion therapy:

• Time From Onset of Symptoms. Time from onset of symptoms to fibrinolytic therapy is an important predictor of MI size and patient outcome 36. The efficacy of fibrinolytic agents in lysing thrombus diminishes with the passage of time 37. Fibrinolytic therapy administered within the first 2 hours (especially the first hour) can occasionally abort MI and dramatically reduce mortality 23,38.
  In contrast, the ability to produce a patent infarct artery is much less dependent on symptom duration in patients undergoing PCI. Several reports claim no influence of time delay on mortality rates when PCI is performed after 2 to 3 hours of symptom duration 39,40. Importantly, after adjustment for baseline characteristics, time from symptom onset to balloon inflation is significantly correlated with 1-year mortality in patients undergoing primary PCI for STEMI 41. The Task Force on the Management of Acute Myocardial Infarction of the European Society of Cardiology 42 and this Committee both recommend a target of medical contact–to-balloon or door-to-balloon time within 90 minutes.
  
• Risk of STEMI. Several models have been developed that assist clinicians in estimating the risk of mortality in patients with STEMI 43–47. Although these models vary somewhat in the factors loaded into the risk-prediction tool and also vary with respect to statistical measures of their discriminative power (eg, C statistic), all the models provide clinicians with a means to assess the continuum of risk from STEMI. When the estimated mortality with fibrinolysis is extremely high, as is the case in patients with cardiogenic shock, compelling evidence exists that favors a PCI strategy.
  
• Risk of Bleeding. Choice of reperfusion therapy is also affected by the patient's risk of bleeding. When both types of reperfusion are available, the higher the patient's risk of bleeding with fibrinolytic therapy, the more strongly the decision should favor PCI. If PCI is unavailable, then the benefit of pharmacological reperfusion therapy should be balanced against the risk.
  
• Time Required for Transport to a Skilled PCI Laboratory. The availability of interventional cardiology facilities is a key determinant of whether PCI can be provided. For facilities that can offer PCI, the literature suggests that this approach is superior to pharmacological reperfusion 48. The trials comparing pharmacological and PCI strategies, however, were conducted before the advent of more recent pharmacological and PCI strategies. When a composite end point of death, nonfatal recurrent MI, or stroke is analyzed, much of the superiority of a PCI strategy is driven by a reduction in the rate of nonfatal recurrent MI (Figure 2) 36. The rate of nonfatal recurrent MI can be influenced both by the adjunctive therapy used and by the proportion of patients who are referred for PCI when the initial attempt at fibrinolysis fails or myocardial ischemia recurs after initially successful pharmacological reperfusion.
  

View larger version (33K): [in this window] [in a new window]   Figure 2 PCI vs fibrinolysis for STEMI. Short-term (4 to 6 weeks; top left) and long-term (top right) outcomes for various end points shown are plotted for STEMI patients randomized to PCI or fibrinolysis for reperfusion in 23 trials (n=7739). Given the frequency of events for each end point in the 2 treatment groups, the number needed to treat (NNT) or number needed to harm (NNH) is shown for the short-term (bottom left) and long-term (bottom right) outcomes. The magnitude of treatment differences for death, nonfatal reinfarction, and stroke varies depending on whether PCI is compared with streptokinase or a fibrin-specific lytic. For example, when primary PCI is compared with alteplase and the SHOCK trial is excluded, the mortality rate is 5.5% vs 6.7% (odds ratio 0.81, 95% confidence interval 0.64 to 1.03, P=0.081) 76a. See references 76 and 76a for additional discussion. Modified with permission from Elsevier (Keeley et al. The Lancet. 2003;361:13–20) 76 ReMI indicates recurrent MI; Rec. Isch, recurrent ischemia; Hem. Stroke, hemorrhagic stroke; and CVA, cerebrovascular accident.

A decision must be made when a STEMI patient presents to a center without interventional cardiology facilities. Fibrinolytic therapy can generally be provided sooner than primary PCI. As the time delay for performing PCI increases, the mortality benefit associated with expeditiously performed primary PCI over fibrinolysis decreases 49. Compared with a fibrin-specific lytic agent, a PCI strategy may not reduce mortality when a delay greater than 60 minutes is anticipated versus immediate administration of a lytic.

Given the current literature, it is not possible to say definitively that a particular reperfusion approach is superior for all patients, in all clinical settings, at all times of day (Danchin N; oral presentation at American Heart Association Scientific Sessions 2003, Orlando, FL, November 2003) 50–52. The main point is that some type of reperfusion therapy should be selected for all appropriate patients with suspected STEMI. The appropriate and timely use of some reperfusion therapy is likely more important than the choice of therapy, given the current literature and the expanding array of options. Clinical circumstances in which fibrinolytic therapy is generally preferred or an invasive strategy is generally preferred are shown in Figure 3.

View larger version (31K): [in this window] [in a new window]   Figure 3 Assessment of reperfusion options for patients with STEMI. STEMI indicates ST-elevation myocardial infarction; PCI, percutaneous coronary intervention; ICH, intracranial hemorrhage. *Applies to fibrin-specific agents (see Figure 15 in the full-text STEMI guidelines). Operator experience greater than a total of 75 primary PCI cases per year. Team experience greater than a total of 36 primary PCI cases per year. This calculation implies that the estimated delay to the implementation of the invasive strategy is greater than 1 hour vs initiation of fibrinolytic therapy immediately with a fibrin-specific agent.

1. STEMI patients presenting to a facility without the capability for expert, prompt intervention with primary PCI within 90 minutes of first medical contact should undergo fibrinolysis unless contraindicated. (Level of Evidence: A)
   

Pharmacological reperfusion
   Indications for fibrinolytic therapy
   Class I

1. In the absence of contraindications, fibrinolytic therapy should be administered to STEMI patients with symptom onset within the prior 12 hours and ST elevation greater than 0.1 mV in at least 2 contiguous precordial leads or at least 2 adjacent limb leads. (Level of Evidence: A)
   
2. In the absence of contraindications, fibrinolytic therapy should be administered to STEMI patients with symptom onset within the prior 12 hours and new or presumably new LBBB. (Level of Evidence: A)
   

   Class IIa

1. In the absence of contraindications, it is reasonable to administer fibrinolytic therapy to STEMI patients with symptom onset within the prior 12 hours and 12-lead ECG findings consistent with a true posterior MI. (Level of Evidence: C)
   
2. In the absence of contraindications, it is reasonable to administer fibrinolytic therapy to patients with symptoms of STEMI beginning within the prior 12 to 24 hours who have continuing ischemic symptoms and ST elevation greater than 0.1 mV in at least 2 contiguous precordial leads or at least 2 adjacent limb leads. (Level of Evidence: B)
   

   Class III

1. Fibrinolytic therapy should not be administered to asymptomatic patients whose initial symptoms of STEMI began more than 24 hours earlier. (Level of Evidence: C)
   
2. Fibrinolytic therapy should not be administered to patients whose 12-lead ECG shows only ST-segment depression except if a true posterior MI is suspected. (Level of Evidence: A)
   

Because the benefit of fibrinolytic therapy is directly related to the time from symptom onset, treatment benefit is maximized by the earliest possible application of therapy. The constellation of clinical features that must be present (although not necessarily at the same time) to serve as an indication for fibrinolysis includes symptoms of myocardial ischemia and ST elevation greater than 0.1 mV, in at least 2 contiguous leads, or new or presumably new LBBB on the presenting ECG 23,54.

Contraindications/cautions
   Class I

1. Healthcare providers should ascertain whether the patient has neurological contraindications to fibrinolytic therapy, including any history of intracranial hemorrhage (ICH), significant closed head or facial trauma within the past 3 months, uncontrolled hypertension, or ischemic stroke within the past 3 months. (See Table 2 for a comprehensive list.) (Level of Evidence: A)
   
2. STEMI patients at substantial (greater than or equal to 4%) risk of ICH should be treated with PCI rather than with fibrinolytic therapy. (See Figure 3 for further management considerations.) (Level of Evidence: A)
   

Complications of fibrinolytic therapy: neurological and other
   Class I

1. The occurrence of a change in neurological status during or after reperfusion therapy, particularly within the first 24 hours after initiation of treatment, is considered to be due to ICH until proven otherwise. Fibrinolytic, antiplatelet, and anticoagulant therapies should be discontinued until brain imaging scan shows no evidence of ICH. (Level of Evidence: A)
   
2. Neurology and/or neurosurgery or hematology consultations should be obtained for STEMI patients who have ICH as dictated by clinical circumstances. (Level of Evidence: C)
   
3. In patients with ICH, infusions of cryoprecipitate, fresh frozen plasma, protamine, and platelets should be given, as dictated by clinical circumstances. (Level of Evidence: C)
   

   Class IIa

1. In patients with ICH, it is reasonable to:
   1. Optimize blood pressure and blood glucose levels. (Level of Evidence: C)
      
   2. Reduce intracranial pressure with an infusion of mannitol, endotracheal intubation, and hyperventilation. (Level of Evidence: C)
      
   3. Consider neurosurgical evacuation of ICH. (Level of Evidence: C)
      
   
   

Combination therapy with glycoprotein IIb/IIIa inhibitors
   Class IIb

1. Combination pharmacological reperfusion with abciximab and half-dose reteplase or tenecteplase may be considered for prevention of reinfarction (Level of Evidence: A) and other complications of STEMI in selected patients: anterior location of MI, age less than 75 years, and no risk factors for bleeding. In two clinical trials of combination reperfusion, the prevention of reinfarction did not translate into a survival benefit at either 30 days or 1 year 54a. (Level of Evidence: B)
   
2. Combination pharmacological reperfusion with abciximab and half-dose reteplase or tenecteplase may be considered for prevention of reinfarction and other complications of STEMI in selected patients (anterior location of MI, age less than 75 years, and no risk factors for bleeding) in whom an early referral for angiography and PCI (ie, facilitated PCI) is planned. (Level of Evidence: C)
   

   Class III

1. Combination pharmacological reperfusion with abciximab and half-dose reteplase or tenecteplase should not be given to patients aged greater than 75 years because of an increased risk of ICH. (Level of Evidence: B)
   

Percutaneous coronary intervention
Coronary Angiography
   Class I

1. Diagnostic coronary angiography should be performed:
   1. In candidates for primary or rescue PCI. (Level of Evidence: A)
      
   2. In patients with cardiogenic shock who are candidates for revascularization. (Level of Evidence: A)
      
   3. In candidates for surgical repair of ventricular septal rupture or severe mitral regurgitation (MR). (Level of Evidence: B)
      
   4. In patients with persistent hemodynamic and/or electrical instability. (Level of Evidence: C)
      
   
   

   Class III

1. Coronary angiography should not be performed in patients with extensive comorbidities in whom the risks of revascularization are likely to outweigh the benefits. (Level of Evidence: C)
   

Primary PCI
   Class I

1. General considerations: If immediately available, primary PCI should be performed in patients with STEMI (including true posterior MI) or MI with new or presumably new LBBB who can undergo PCI of the infarct artery within 12 hours of symptom onset, if performed in a timely fashion (balloon inflation within 90 minutes of presentation) by persons skilled in the procedure (individuals who perform more than 75 PCI procedures per year). The procedure should be supported by experienced personnel in an appropriate laboratory environment (performs more than 200 PCI procedures per year, of which at least 36 are primary PCI fo