ACC/AHA Guidelines for the Management of Patients with ST Elevation Myocardial Infarction;

2004 (Part II)

Ahmad Aslam, M.D.

Prasantha Bathini, M.D.

Robert Smith, M.D.

Cardiac Cath Conference

July 20, 2004

Summary of Initial Management

• Prehospital Issues• Initial ER Evaluation• Targeted History• Targeted Physical

Exam• Laboratory

Evaluations• ECG• Imaging

• Oxygen• Nitrates• Morphine• ASA• Beta Blockers• Selection of

Reperfusion Strategy

Initial Recognition and Management in the ED

“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.”

Class I, Level of Evidence: B

Step II: Determine whether fibrinolysis or invasive strategy is preferred

Step I: Assess time and risk- Time since onset of symptoms- Risk from STEMI- Risk of fibrinolysis- Time required for transport to a skilled PCI lab

Fibrinolysis is generally preferred if

- Early presentation (3 hours or less and delay to invasive strategy) - Invasive strategy is not an option - Cath lab not available - Vascular access difficulties - Lack of access to a skilled lab - Delay to invasive strategy

Invasive strategy is generally preferred if - Skilled PCI lab available with surgical backup - High risk from STEMI - Cardiogenic shock - Killip class > or = to 3 - Contraindications to fibrinolysis including increased risk of bleeding and ICH - Late presentation - Symptom onset more than 3 hours - Diagnosis of STEMI is in doubt

TIMI Risk Score for UA/NSTEMI

Historical

Age > or = to 65 > or = to 3 CAD Risk Factors Known CAD (> or = to 50% stenosis) ASA use in the last 7 days

Presentation

Recent Angina (> or = to 24 hours) Elevated Cardiac Markers ST Deviation > 0.5mm

Points

1 1 1 1

1 1 1

RISK SCORE = TOTAL POINTS (0-7)

TIMI Risk Score for UA/NSTEMI

Antman et al., JAMA 2000;284:835-842

TIMI STEMI Risk ScoreApplies to patients with chest pain >30 min, symptom onset <6 hrs, ST elevation

HistoryAge > or = to 75Age 65-74Previous Angina, HTN, or DM

ExaminationWeight < 67 kg (150#)HR > 100Systolic BP < 100mmHgKillip Class II – IV

PresentationAnterior ST Elevation or LBBBTime to Treatment > 4 hours

Points 3 2 1

1 2 3 2

1 1

RISK SCORE = TOTAL POINTS (0-14)

TIMI STEMI Risk Score

Morrow et al. Circ. 2000;102:2031-2037

Fibrinolytic Therapy

Class I

STEMI patients presenting to a facility without the capacity for expert, prompt intervention (primary PCI with 90 minutes of first medical contact) should undergo fibrinolytic therapy. (Level of Evidence: A)

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 0.1mV in at least 2 contiguous precordial leads or at least 2 adjacent limb leads. (Level of Evidence: A)

In the absence of contraindications, fibrinolytic therapy should be administered to patients with symptom onset within the prior 12 hours and new or presumably new LBBB. (Level of Evidence: A)

Fibrinolytic Therapy

Class IIa

In the absence of contraindications, it is reasonable to administer fibrinolytic therapy to STEMI patients with symptom onset within the prior 12 hours and ECG findings consistent with true posterior MI. (Level of Evidence: C)

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

Fibrinolytic Therapy

Class IIIFibrinolytic therapy should not be administered to asymptomatic patients whose initial symptoms of STEMI began more than 24 hours earlier. (Level of Evidence: C)

Fibrinolytic therapy should not be administered to patients whose ECG shows only ST segment depression unless true posterior MI is suspected. (Level of Evidence: A)

Contraindications and Cautions for Fibrinolysis use in STEMI

Absolute Contraindications - Any prior ICH - Known structural cerebral vascular lesion (e.g., AVM) - Known malignant intracranial neoplasm (1o or 2o) - Ischemic stroke within 3 months except acute ischemic stroke within 3 hours - Suspected aortic dissection - Active bleeding or bleeding diathesis (except menses) - Significant closed head or facial trauma within 3 months

Relative Contraindications - History of chronic, severe, poorly controlled HTN - Severe, uncontrolled HTN on presentation (SBP>180, DBP>110) - Hx of prior ischemic stroke >3 months, dementia, or known IC pathology not listed in contraindications - Traumatic or prolonged CPR (>10 min) or major surgery (<3 weeks) - Recent internal bleeding (2-4 weeks) - Noncompressible vascular punctures - For Streptokinase/Anistreplase: prior exposure (>5 days) or prior allergic rxn - Pregnancy - Active peptic ulcer - Current use of anticoagulants; the higher the INR, the higher the risk

Percutaneous Coronary Intervention

Class I

If immediately available, primary PCI should be performed in patients with STEMI (including posterior MI), or in patients with new LBBB who can undergo PCI of the infarct artery within 12 hours of onset of symptoms. (Level of Evidence: A)

PCI must be performed in a timely fashion (door balloon time 90 minutes) by persons skilled in the procedure (greater than 75/year). (Level of Evidence: A)

Percutaneous Coronary Intervention

Class IPrimary PCI should be performed for patients younger than 75 years with STEMI or LBBB who develop shock within 36 hours of MI and are suitable for revascularization that can be performed within 18 hours of shock. (Level of Evidence: A)

Primary PCI should be performed in patients with severe CHF and/or pulmonary edema (Killip class III) and onset of symptoms within 12 hours. Door balloon should be within 90 minutes. (Level of Evidence: B)

Percutaneous Coronary Intervention

Class IIaPrimary PCI is reasonable for patients >75 yrs who develop shock within 36 hours of MI and are suitable for revascularization that can be performed within 18 hours of shock. (Level of Evidence: B)

It is reasonable to perform primary PCI for patients with onset of symptoms in prior 12-24 hours and severe CHF (Level of Evidence: C), hemodynamic or electrical instability (Level of Evidence: C), or persistent ischemic symptoms (Level of Evidence: C)

Percutaneous Coronary Intervention

Class IIIPCI should not be performed in a non-infarct artery at the time of PCI in patients without hemodynamic compromise. (Level of Evidence: C)

Primary PCI should not be performed in asymptomatic patients more than 12 hours after onset of STEMI if they are hemodynamically and electrically stable. (Level of Evidence: C)

Acute Surgical Reperfusion

Class IFailed PCI with persistent pain or hemodynamic instability in patient with suitable anatomy. (Level of Evidence: B)

Persistent or refractory ischemia in patients with suitable anatomy, with significant myocardium at risk, and who are not candidates for fibrinolysis or PCI. (Level of Evidence: B)

Acute Surgical Reperfusion

Class IAt the time of surgical repair of post-infarction ventricular septal rupture or mitral valve insufficiency. (Level of Evidence: B)

Cardiogenic shock in patients <75yrs with STEMI, LBBB, posterior MI who develop shock within 36 hours of STEMI and have severe multivessel or LM disease. (Level of Evidence: A)

Life threatening ventricular arrhythmias in the presence of severe multivessel or LM disease. (Level of Evidence: B)

Ancillary Therapy: UFH

Class IPatients undergoing PCI or surgical Revascularization should be given UFH. (Level of Evidence: C)

UFH should be given intravenously to patients undergoing reperfusion therapy with alteplase, reteplase, or tenecteplase. (Level of Evidence: C)

Ancillary Therapy: UFHClass I

UFH should be given intravenously to patients treated with nonselective fibrinolytic agents (streptokinase, anistreplase, urokinase) who are at high risk for systemic emboli (e.g., AFIB, large anterior MI, known LV thrombus). (Level of Evidence: C)

Platelet counts should be monitored daily in patients receiving UFH. (Level of Evidence: C)

Class IIBIt may be reasonable to administer UFH to patients undergoing reperfusion therapy with streptokinase

Ancillary Therapy: LMWH

Class IIBLMWH may be acceptable alternative to UFH for patients <75yrs who are receiving fibrinolytic therapy. (Level of Evidence: B)

Class IIIShould not be used for patients >75yrs who are receiving fibrinolytic therapy. (Level of Evidence: B)

Should not be used in patients with significant renal dysfunction (SCr <2.5 for men, 2.0 for women). (Level of Evidence: B)

Ancillary Therapy: Bivalirudin

Class IIa

In patients with known HIT, it is reasonable to consider bivalirudin as an alternative to UFH to be used with streptokinase. (Level of Evidence: B)

Dosing is 0.25mg/kg followed by IV infusion of 0.5mg/kg/hr for the first 12 hours and 0.25mg/kg/hr for the subsequent 36 hours. The infusion rate should be reduced if the PTT is <75 seconds within the first 12 hours.

Ancillary Therapy: Thienopyridines

Class IIn patients who have undergone diagnostic LHC and for whom PCI is planned, clopidogrel should be started and continued for at least 1 month for bare metal stents and several months for DES’s (at least 3 months for SES and 6 months for PES). If patients are not at high risk for bleeding, it should be given for up to 12 months for DES’s. (Level of Evidence: B)

In patients taking clopidogrel in whom CABG is planned, the drug should be withheld for at least 5 days (and preferably 7), unless the urgency of CABG outweighs the risk of bleeding. (Level of Evidence: B)

Ancillary Therapy: Thienopyridines

Class IIaClopidogrel is probably indicated in patients receiving fibrinolytic therapy who are unable to take aspirin because of hypersensitivity or major GI intolerance. (Level of Evidence: C)

General Statements:Clopidogrel combined with ASA is recommended for patients undergoing stent implantation

There are no safety data comparing 300mg vs. 600mg loading doses

Routine administration of clopidogrel is not recommended in patients who have not undergone LHC and in whom CABG might be performed if necessary

Ancillary Therapy: GP IIb/IIIa Inhibitors

Class IIaIt is reasonable to start therapy with abciximab as early as possible before primary PCI (with or without stenting) in patients with STEMI. (Level of Evidence: B)

Class IIbTreatment with tirofiban or eptifibatide may be considered before primary PCI (with or without stenting) in patients with STEMI. (Level of Evidence: C)

Ancillary Therapy: Inhibition of RAAS

Class IIn the absence of hypotension (SBP <100) or other contraindications, an oral ACE-I should be administered within the first 24 hours to patients with anterior MI, pulmonary congestion, or LVEF <40%. (Level of Evidence: A)

An ARB should be administered to patients who are intolerant of ACE-I and who have either clinical or radiographic signs of CHF or if LVEF <40%. Valsartan and Candesartan have established efficacy for this recommendation. (Level of Evidence: C)

Ancillary Therapy: Inhibition of RAAS

Class IIaIn the absence of hypotension (SBP <100) or other contraindications, an oral ACE-I administered within the first 24 hours can be useful in patients without anterior MI, pulmonary congestion, or LVEF <40%. (Level of Evidence: B)

Class IIIAn IV ACE-I should not be given to patients within 24 hours of STEMI because of the risk of hypotension. (Level of Evidence: B)

Strict Glucose Control During STEMI

Class I

An insulin infusion to normalize blood glucose is recommended for patients with STEMI and complicated courses. (Level of Evidence: B)

Class IIa

During the acute phase (first 24-48 hrs) of the management of STEMI in patients with hyperglycemia, it is reasonable to administer an insulin infusion, even in patients with an uncomplicated course. (Level of Evidence: B)

After the acute phase of STEMI, it is reasonable to individualize treatment, selecting from insulin, insulin analogs, and oral hypoglycemics. (Level of Evidence: C)

MagnesiumClass IIa

It is reasonable that documented Mg deficits be corrected, especially in patients receiving diuretics before the onset of STEMI. (Level of Evidence: C)

It is reasonable that episodes of torsades de pointes associated with a prolonged QT interval be treated with 1-2 grams of IV Mg administered as an IV bolus over 5 minutes. (Level of Evidence: C)

Class III

In the absence of electrolyte abnormalities or documented torsades, routine IV Mg should not be administered to STEMI patients at any level of risk. (Level of Evidence: A)

Calcium Channel Blockers

Class IIa

It is reasonable to give verapamil or diltiazem to patients in whom beta blockers are ineffective or contraindicated (e.g., bronchospastic disease) for relief of ongoing ischemia or control of a rapid ventricular response with AFIB or flutter after STEMI. This should be done only in the absence of CHF, LV dysfunction, or AV block. (Level of Evidence: C)

Calcium Channel Blockers

Class IIIDiltiazem and verapamil are contraindicated in patients with STEMI and associated LV systolic dysfunction or AV block. (Level of Evidence: A)

Nifedipine (immediate release form) is contraindicated in treatment of STEMI because of the reflex sympathetic activation, tavhycardia, and hypotension associated with its use. (Level of Evidence: B)

Hospital Management: CCU

Class ISTEMI patients should be admitted to a quiet and comfortable environment that provides continuous ECG monitoring, pulse oximetry, and has ready access to facilities for hemodynamic monitoring and defibrillation. (Level of Evidence: C)

The patients medication regimen should be reviewed to confirm the administration of ASA and beta blockers in an adequate dose to control heart rate and to assess the need for IV NTG for control of angina, HTN, or CHF. (Level of Evidence: A)

Hospital Management: CCU

Class IThe ongoing need for oxygen therapy should be assessed by monitoring arterial oxygen saturation. When stable for 6 hours, the patient should be reassessed for oxygen need (SaO2 <90%) and discontinuation of supplemental O2 should be considered. (Level of Evidence: C)

Nursing care should be provided by individuals certified in critical care, with staffing based on the specific needs of the patients and provider competencies, as well as organizational priorities. (Level of Evidence: C)

Hospital Management: CCU

Class ICare of STEMI patients in the CCU should be structured around protocols derived from practice guidelines. (Level of Evidence: C)

ECG monitoring leads should be based on the rhythm to optimize detection of ST deviation, axis shift, conduction defects, and dysrhythmias. (Level of Evidence: B)

Hospital Management: CCU

Class III

It is not an effective use of the CCU environment to admit terminally ill, “do not resuscitate” patients with STEMI, because clinical and comfort needs can be provided outside of a critical care environment. (Level of Evidence: C)

Hospital Management: Stepdown

Class IIt is a useful triage strategy to admit low-risk STEMI patients who have undergone successful PCI directly to the stepdown unit for post PCI care rather than to the CCU. (Level of Evidence: C)

STEMI patients originally admitted to the CCU who demonstrate 12-24 hours of clinical stability (absence of recurrent ischemia, heart failure, or hemodynamically compromising dysrhythmias) should be transferred to the stepdown unit. (Level of Evidence: C)

Hospital Management: StepdownClass IIa

It is reasonable for patients recovering from STEMI who have clinically symptomatic heart failure to be managed on the stepdown unit, provided that facilities for continuous monitoring of pulse oximetry and appropriately skilled nurses are available. (Level of Evidence: C)

It is reasonable for patients recovering from STEMI who have arrhythmias that are well tolerated (AFIB, NSVT) to be managed on the stepdown unit, provided that facilities for continuous monitoring of the ECG, defibrillators, and appropriately skilled nurses are available. (Level of Evidence: C)

Hospital Management: Stepdown

Class IIb

Patients recovering from STEMI who have clinically significant pulmonary disease requiring high flow supplemental oxygen or non-invasive mask ventilation/BiPAP/CPAP may be considered for care on a stepdown unit, provided that facilities for continuous monitoring of pulse oximetry and appropriately skilled nurses with a sufficient nurse:patient ratio are available. (Level of Evidence: C)

Summary

• Targeted History• Physical (include neuro)• ECG (RV, Posterior)• Lab• CXR• O2

• Nitrates• MSO4

• ASA• Beta Blockers

• Select Reperfusion Strategy

• UFH/LMWH• Thienopyridines • GPIIb/IIIa• ACE-I• Glucose Control• Magnesium• CCB• CCU/Stepdown

PCI Fibrinolysis

Advantages Superior patency rate Widely available

Reduced Mortality, RI, MI

Operator experience

Less ICH Prompt on site

Lower early mortality Simple to give a bolus

Superior in CG shock

Probably superior to fibrinolysis overall

Disadvantages Expertise required Systemic bleeding

Limited access / time ICH

Summary