History

• Obtaining a thorough history of presenting symptoms, as well as previous similar episodes and known risk factors, is essential
• Pain ^c1
  • Usually characterized as substernal pressure or tightness;^r6 varies in intensity, but may increase in crescendolike pattern to become very severe, especially in ST-elevation myocardial infarction ^c2
  • May be bilateral or unilateral, but occurs more commonly on left side
  • May radiate to left or right arm, both arms, neck, or lower jaw ^r6c3c4c5
  • May be associated with diaphoresis, dyspnea, nausea, vomiting, fatigue, or syncope ^{r6c6c7c8c9c10c11}
  • May be precipitated by exertion but may also occur at rest ^c12c13
  • There is disagreement over the diagnostic significance of relief with nitroglycerin; typical pattern involves prompt relief within several minutes of taking sublingual nitroglycerin ^c14
  • Duration usually exceeds 10 minutes^r3 and may last for hours, especially in ST-elevation myocardial infarction^r7
  • May be absent; may be atypical in nature or distribution
    • Atypical presentations are more common in patients aged 75 years or older, in females, and in patients with diabetes, chronic kidney disease, or dementia ^r1
      • Examples include dyspnea without pain, or pain in arms, neck, or lower jaw without substernal component ^{c15c16c17c18c19c20c21c22c23c24c25c26}
  • Characteristics that suggest nonischemic pain include: ^r1
    • Pleuritic in nature ^c27
    • Predominantly located in mid or lower abdomen ^c28c29
    • Localized by fingertip ^c30
    • Reproducible by palpation or movement ^c31c32
    • Brief duration (eg, seconds) or continuous for more than 24 hours^r6c33
    • Most severe at onset ^c34
    • Radiation to legs ^c35c36
    • Sharp or stabbing quality ^r6c37c38

Physical examination

• Findings may be unremarkable, especially with non–ST-elevation myocardial infarction and unstable angina ^c39
• Appearance may be pale or diaphoretic; patient may be anxious ^c40c41c42
• Heart rate may be within the reference range, low, or rapid ^c43c44c45
• Blood pressure may be within the reference range, elevated (owing to pain), or low (owing to cardiogenic shock) ^c46c47c48
• Respiratory rate is usually within the reference range, but it may be elevated in patients with extensive infarction and heart failure; Cheyne-Stokes respiration may occur in heart failure or cardiogenic shock ^c49c50c51
• Jugular venous distention may indicate heart failure or right ventricular infarction ^c52
• Heart tones are often muffled. An S₄ is common; an S₃ may be audible in patients with heart failure, either preexisting or resulting from acute left ventricular dysfunction due to ischemia or infarction ^c53c54c55
• A new or worse systolic murmur may indicate papillary muscle ischemia or rupture ^c56
• Fine rales may be heard in patients with heart failure or cardiogenic shock ^c57

Causes

• Coronary thrombosis, precipitated by disruption of atheromatous plaque (most common) ^c58
• Other ischemic causes
  • Nonthrombotic causes of partial or complete obstruction to coronary blood flow (eg, embolus, spasm) ^c59c60c61
  • Other conditions in which myocardial oxygen supply cannot meet demand (eg, arrhythmia, thyrotoxicosis, hypotension, anemia, respiratory failure, overexertion) ^{c62c63c64c65c66c67c68}
  • Cocaine and methamphetamine cause acute coronary syndromes through superimposed myocardial demand; cocaine also induces coronary thrombosis, arterial dissection, coronary artery spasm, and direct myocardial toxicity ^r1c69c70
  • Spontaneous coronary artery dissection ^r8c71
    • Epicardial coronary artery dissection not associated with atherosclerosis or trauma; not iatrogenic
    • May be a cause of 1% to 4% of acute coronary syndromes cases overall; most common cause of pregnancy-associated myocardial infarction ^r8
  • Patients with ischemic myocardial infarction but no angiographic obstructive coronary artery disease (at least 50% diameter stenosis in a major epicardial vessel) are described as having MINOCA; prevalence estimated to be about 6% among patients diagnosed with myocardial infarction ^r4r5

Risk factors and/or associations

Primary diagnostic tools

• Primary means of diagnosis are history, physical examination, ECG, and serum biomarkers ^c113c114
  • Features of history and physical examination that correlate with a high likelihood of acute coronary syndromes include: ^r11
    • Chest or left arm pain or discomfort that reproduces symptomatic character of previously documented angina
    • Known history of coronary artery disease
    • New mitral regurgitation murmur
    • Hypotension
    • Diaphoresis
    • Rales or pulmonary edema
  • Always consider a cardiac cause of chest pain even if gastrointestinal medications relieve pain
• All patients with symptoms suggestive of acute coronary syndromes should have a 12-lead ECG performed within 10 minutes of presentation ^r1
  • If the initial ECG result is not diagnostic and the patient continues to experience symptoms, an ECG should be repeated at 15- to 30-minute intervals within the first hour ^r1
  • Serial ECG tests are also helpful in following evolution of ischemic process
  • Supplemental leads should be applied if posterior or inferior infarction is suspected and if 12-lead ECG is not diagnostic
  • Normal ECG results do not preclude diagnosis of acute coronary syndromes; normal tracing results are seen in 1% to 6% of cases ^r1
• Draw blood from all patients at presentation with symptoms suggestive of acute coronary syndromes to measure cardiac biomarkers ^r1
  • Cardiac-specific troponin levels (T or I) are highly sensitive and specific; they are the preferred diagnostic biomarker for initial testing ^c115c116
• Obtain a chest radiograph for all patients ^c117
• Choice of other studies is guided by whether the ECG changes suggest ST-elevation myocardial infarction or non–ST-elevation myocardial infarction/unstable angina; in the latter case, also guided by validated risk assessment tools such as the TIMI score (Thrombolysis in Myocardial Infarction)^r12 and the GRACE score (Global Registry of Acute Coronary Events)^r13
  • Coronary angiography is recommended for most patients with ST-elevation myocardial infarction or high-risk non–ST-elevation myocardial infarction/unstable angina ^r1r2
    • Coronary angiography is essential for visualizing the coronary anatomy and distribution and for locating and quantifying intraluminal blockages; in many cases, it can be coupled with therapeutic intervention (reperfusion) ^r1
    • Immediate coronary angiography (ie, within 90-120 minutes) is recommended when percutaneous intervention is available, such as in: ^r1
      • ST-elevation myocardial infarction ^r2
      • Unstable non–ST-elevation myocardial infarction/unstable angina with: ^r1
        • Refractory ischemic pain
        • Heart failure
        • New or worsening mitral regurgitation
        • Hemodynamic instability
        • Sustained ventricular arrhythmias
    • Early coronary angiography (ie, within 24 hours) is recommended in patients with non–ST-elevation myocardial infarction/unstable angina who are at intermediate or high risk, as follows: ^r1
      • TIMI score:^r14 3 or more
      • GRACE score:^r13 more than 140
      • Elevated troponin levels demonstrating rise or fall
      • New ST depression
    • For patients with non–ST-elevation myocardial infarction who are stable, coronary angiography may be delayed or deferred unless a new ischemic event occurs ^r1
  • Other early imaging studies such as echocardiography and radionuclide testing may be helpful in localizing the area of ischemia or injury, assessing the extent of injury, and evaluating possible alternative diagnoses ^r5
  • CT angiography or stress testing can be used to further evaluate patients in whom an acute coronary syndrome was initially suspected but whose ECGs and troponin levels are not diagnostic ^r1c118c119

Laboratory

• Troponin I or T levels should be obtained at presentation and at 3 to 6 hours after onset of symptoms if using sensitive assays;^r1time intervals can be shortened with the use of highly sensitive cardiac troponin assays^r15c120c121
  • Algorithms to include or exclude acute myocardial infarction have been developed for screening of patients presenting with chest pain based on consecutive high-sensitivity troponin levels measured at 0 and either 1, 2, or 3 hours ^r15r16
  • Both peak level and degree of change are diagnostically important
  • Criteria for a laboratory diagnosis of myocardial necrosis include: ^r5
    • Troponin I or T levels above the 99th percentile of the upper norm, plus a serial increase or decrease of at least 20% of an elevated level
    • For troponin I or T levels that do not exceed the 99th percentile, a change of 3 standard deviations or more from the initial value is diagnostic
  • Further levels should be obtained if interim symptoms or ECG changes suggest ongoing ischemia
• Creatine kinase–MB (myocardial band) fraction (formerly the diagnostic biomarker of choice) is not as sensitive as troponin and is not commonly used diagnostically, but because of its shorter half-life, it is sometimes useful in assessing the magnitude of the infarct and in detecting early extension of an infarct before existing troponin elevation has declined ^r17c122
• B-type natriuretic hormone measured at presentation or shortly thereafter provides a baseline against which subsequent levels can be compared to gain prognostic information and to help guide therapy ^r3c123
  • Rise in level of B-type natriuretic hormone is associated with worse prognosis
• Fasting lipid profile is recommended, preferably within 24 hours of admission, to assess for dyslipidemia ^r1r2c124

Imaging

• Obtain a chest radiograph as a baseline for subsequent comparison and to assess for pulmonary vascular congestion ^r17c125
• Echocardiography is recommended to evaluate regional and global left ventricular function and to evaluate differential diagnoses ^r15c126
  • Regional wall motion abnormalities seen on echocardiogram may provide indirect evidence and localization of ischemia or necrosis (eg, in patients with nondiagnostic ECG or in whom cardiac biomarkers were not measured) ^r2
  • Additionally, echocardiography is often used early during the post–myocardial infarction period to assess left ventricular function, an important prognostic indicator
• Radionuclide imaging can be used to assess wall motion, but it also reliably detects loss of myocardial tissue viability ^r15c127
  • Useful means of diagnosing myocardial necrosis when biomarkers have not been measured
  • Can also be used to exclude a diagnosis of myocardial infarction when normal function and viability are demonstrated
• CT angiography is recommended as a reasonable means of excluding acute coronary syndrome in patients with a low to intermediate likelihood of coronary artery disease and whose ECG and troponin levels are not diagnostic ^r1r15c128

Functional testing

• ECG ^r5c129
  • Always compare ECG with a previous tracing if available
  • If inferior myocardial infarction is suspected, apply right-sided leads V4R, V5R, and V6R and posterior leads V7 to V9, in addition to traditional leads
  • ECG patterns
    • New ST-segment elevation at the J point of 2 contiguous leads, persisting for 20 minutes or longer, suggests ST-elevation myocardial infarction ^r5
      • Cut point of 1 mm or greater in all leads other than V2 and V3, where the following cut points apply: ^r5
        • 2 mm or greater in males aged 40 years or older
        • 2.5 mm or greater in males younger than 40 years
        • 1.5 mm or greater in females regardless of age
      • May be preceded by hyperacute T waves
      • Reciprocal ST-segment depression may be observed
    • New horizontal or down-sloping ST-segment depression and T-wave changes suggest non–ST-elevation acute coronary syndrome ^r5
      • Criteria are as follows:
        • 0.5 mm or greater ST-segment depression in 2 contiguous leads and/or T-wave inversion 0.1 mV or higher in 2 contiguous leads with prominent R wave or R/S ratio greater than 1 ^r5
  • Other findings that commonly accompany myocardial ischemia include conduction delays, arrhythmias, and decrease in amplitude of precordial R waves (compared with previous tracings)
  • Left bundle branch blocks may obscure typical findings of infarction
  • An acute coronary syndrome is not excluded by a normal ECG result or a result in which the criteria are not fully met
  • Pseudonormalization may occur during the evolution of an acute coronary syndrome as ST-segment depression transitions to ST-segment elevation

Procedures

Other diagnostic tools

• Risk assessment stratification
  • TIMI score ^r12r14c132
    • Used to stratify risk in patients with non–ST-elevation myocardial infarction/unstable angina to determine disposition (ICU versus other settings) and to identify high-risk patients who will benefit from aggressive antithrombotic and early invasive management (versus ischemia-guided or noninvasive medical management)
    • 1 point is tabulated for each of the following criteria:
      • Age 65 years or older ^r12
      • 3 or more risk factors for coronary artery disease ^r12
      • Prior coronary stenosis of 50% or more ^r12
      • ST deviation
      • 2 or more anginal events in prior 24 hours ^r12
      • Use of aspirin in prior 7 days ^r12
      • Elevated cardiac biomarker levels
    • Scores correlate with risk of all-cause mortality, new or recurrent myocardial infarction, or requirement for urgent revascularization
      • Score of 0 or 1: 4.7% ^r12
      • Score of 2: 8.3% ^r12
      • Score of 3: 13.2% ^r12
      • Score of 4: 19.9% ^r12
      • Score of 5: 26.2% ^r12
      • Score of 6 or 7: 40.9% ^r12
  • GRACE score ^r13r18c133
    • More complex instrument that likewise predicts mortality based on points assigned for Killip class, systolic blood pressure, heart rate, serum creatinine level, cardiac arrest at admission, ST-segment deviation, and cardiac enzyme levels; the point total can be matched to the mortality risk on a published nomogram^r18
    • Can be used for risk stratification of patients with either ST-elevation myocardial infarction or non–ST-elevation myocardial infarction/unstable angina

Most common

• Life-threatening cardiopulmonary conditions should be considered immediately
  • Pulmonary embolism ^c134d1
    • Presents with chest pain, dyspnea, tachypnea, and hypoxia; tachycardia, ST abnormalities on ECG, and elevated cardiac troponin levels may be present
    • Chest pain is usually pleuritic; dyspnea is usually prominent and may be overwhelming; edema, tenderness, or a palpable "cord" may be present in 1 or both lower extremities
    • Multidetector-row CT angiography is diagnostic for pulmonary embolism; shows a thrombus or thrombi in pulmonary vessels
  • Dissecting aortic aneurysm ^c135d2
    • Presents with sudden, severe chest pain that may radiate to the back; may be associated with hypotension or diaphoresis; nonspecific ECG changes and elevated cardiac troponin levels may be present ^d3
    • Pain is characterized as tearing or ripping
    • Murmur of aortic insufficiency may be audible; pulses may be asymmetrical
    • CT with contrast enhancement is diagnostic for dissecting aortic aneurysm
• Other cardiac conditions
  • Pericarditis ^c136d4
    • Presents as pleuritic precordial or retrosternal pain that may radiate to the back, neck, and left shoulder/arm; ECG often shows PR-segment depression and ST-segment elevation; troponin levels may be elevated
    • Pain is worse on inspiration, in supine position, during swallowing, and during movement; pain is improved when the patient is seated and leaning forward. A pericardial friction rub is sometimes heard on auscultation
    • Echocardiography is the diagnostic study of choice, usually demonstrating effusion with or without thickening of the pericardium
  • Mitral valve prolapse ^c137d5
    • May present with palpitations, fatigue, syncope, and orthostatic hypotension
    • A midsystolic click and systolic murmur may be audible
    • Echocardiography is diagnostic, showing prolapsing valve with or without valve thickening
  • Takotsubo cardiomyopathy ^c138
    • Transient cardiac syndrome involving left ventricular apical akinesis
    • Produces chest pain, ST elevation, and sometimes elevated cardiac enzyme levels
    • Usually brought on by intense emotional (eg, bereavement) or physical stress; exact cause is unknown
    • Most patients are postmenopausal females
    • Diagnosis is confirmed by coronary angiogram showing normal coronary artery anatomy and left ventricular apical ballooning
• Noncardiac conditions
  • Cholecystitis ^c139d6
    • Presents with epigastric pain that may be poorly localized at first, mimicking anginal pain
    • Nausea and vomiting are often prominent, and there is tenderness to palpation in the right upper quadrant; troponin levels are not elevated
    • Right upper quadrant ultrasonography is usually diagnostic, showing an inflamed gallbladder; stones and ductal dilatation may be evident
  • Pancreatitis ^c140d7
    • Presents with epigastric pain, often with radiation to the back; pain may be severe
    • Tenderness to palpation of the upper abdomen, sometimes with rebound tenderness
    • Abdominal CT or ultrasonography shows inflammation of the pancreas; lipase and amylase levels are elevated
  • Perforated peptic ulcer ^c141d8
    • Presents with sudden severe epigastric pain; may involve associated hypotension or shock
    • Tenderness to palpation of the upper abdomen, with peritoneal signs
    • Upright chest radiograph finds free air under diaphragm; abdominal CT scan may localize ulcer and perforation
  • Esophageal spasm ^c142
    • May present with epigastric pain or tightness, which may be relieved by sublingual nitroglycerin
    • May be precipitated by swallowing; associated with dysphagia
    • Diagnosis is confirmed by manometry (which finds premature rapid contractions) or by the appearance of corkscrew esophagus on barium swallow
  • Costochondritis ^c143
    • May present with severe pain in sternal area
    • Characterized by exacerbation with chest motion (eg, respiration, rotation of torso)
    • Differentiated from acute coronary syndromes by characteristic exacerbation with physical maneuvers and absence of ECG abnormalities
  • Prodromal or early herpes zoster (varicella-zoster infection) ^c144d9
    • Infection in midthoracic dermatomes can present as excruciating pain that mimics acute coronary syndromes
    • Not associated with dyspnea, ECG changes, or troponin release
    • Diagnosis may not become apparent until lesions appear; distribution and characteristic features (clustered vesicles) of the lesions are usually diagnostic, but polymerase chain reaction test can be used for confirmation

Admission criteria

All patients with a confirmed acute coronary syndrome require admission to hospital telemetry unit ^r1r2

• Patients with symptoms suggesting an acute coronary syndrome, but without diagnostic ECG changes or elevated troponin levels, may be observed in a telemetry unit, chest pain unit, or emergency department while undergoing serial ECGs, troponin measurements, and other testing ^r1

For patients with ST-elevation myocardial infarction who present at a facility without the ability to perform percutaneous coronary intervention, transfer to a hospital with appropriate facilities if the transfer can be achieved within first-medical-contact-to-balloon-time window of 90 minutes or less ^r2

Recommendations for specialist referral

• Consult a cardiologist for all patients with a confirmed acute coronary syndrome
• Refer patients with symptoms suggestive of myocardial ischemia, but without evidence of an acute coronary syndrome, to a cardiologist

Drug therapy

• Nitrates
  • Nitroglycerin ^r1r2c145
    • Initial route is sublingual; IV administration is indicated if ischemic pain persists after 3 sublingual doses
    • Sublingual
      • Nitroglycerin Sublingual tablet; Adults: 1 tablet (300 mcg, 400 mcg, or 600 mcg) SL, dissolved under the tongue or in buccal pouch at attack onset; may repeat with 1 tablet every 5 minutes PRN for up to 3 tablets. If chest pain persists after 3 tablets, prompt medical attention should be sought. Guidelines suggest patients with persistent chest pain following 1 dose, should seek prompt medical attention. May use prophylactically 5 to 10 minutes before participating in activities that may precipitate an acute attack.
    • IV
      • Nitroglycerin Solution for injection; Adults: Initially, 5 mcg/minute continuous IV infusion. Titrate by 5 mcg/minute IV every 3 to 5 minutes until clinical response, or to a dose of 20 mcg/minute IV. May further increase dosage in increments of 10 mcg/minute, and if desired effect still not achieved, may increase in increments of 20 mcg/minute. Max titration: 20 mcg/minute every 3 to 5 minutes. Usual dose: 5 to 100 mcg/minute. Max: 200 mcg/minute.
• Analgesia
  • Morphine ^r1r2c146
    • Morphine Sulfate Solution for injection; Adults: Initially, 2 to 5 mg IV every 5 to 30 minutes PRN for pain; some patients may require maintenance doses of 4 to 8 mg IV every 4 to 6 hours.
    • Monitor blood pressure and respiratory rate
• Antiplatelet drugs
  • Aspirin ^r1r2c147
    • Provides analgesia and reduces platelet aggregation to inhibit thrombus formation
    • Aspirin Oral tablet; Adults: 160 mg to 325 mg PO non-enteric coated tablet, chewed and swallowed immediately, regardless of concomitant fibrinolytic therapy. Maintenance: 75 mg to 162 mg PO once daily.
    • Recommended maintenance dose of aspirin is 81 mg for indefinite period
    • Avoid other NSAIDs
  • P2Y₁₂ inhibitors ^{r31r32r33c148}
    • Reduce platelet aggregation by blocking the P2Y₁₂ adenosine diphosphate receptor on platelets, which reduces thrombus formation, increases bleeding time, and reduces blood viscosity
    • For patients with ST-elevation myocardial infarction undergoing percutaneous coronary intervention, prasugrel or ticagrelor is preferred over clopidogrel; cangrelor may be an option for patients who are unable to take an oral P2Y₁₂ inhibitor ^r25
    • Prasugrel ^c149c150
      • FDA-approved for patients with acute coronary syndromes undergoing percutaneous coronary intervention; not FDA-approved for medical management of acute coronary syndromes
      • Recommended in patients who are proceeding to percutaneous coronary intervention if there are no contraindications ^r15
      • Prasugrel is preferred over ticagrelor in patients with non–ST-elevation myocardial infarction who undergo percutaneous coronary intervention ^r15
      • Not recommended for patients older than 75 years
      • Greater antiplatelet effect with significant reduction in risk of thrombotic events compared with clopidogrel or ticagrelor; greater risk of bleeding compared with clopidogrel or ticagrelor ^r34
      • In elderly or low-weight patients, a reduced dose of prasugrel compared with the standard dose of ticagrelor is associated with maintained anti-ischemic efficacy while protecting against excess risk for bleeding ^r35
      • Prasugrel Oral tablet; Adults and Geriatric Adults less than 75 years of age and weighing less than 60 kg: 60 mg PO as a loading dose, then consider a lower maintenance dose of 5 mg PO once daily. Optimal duration of therapy is not known. Also give aspirin 75 mg/day to 325 mg/day PO.
      • Prasugrel Oral tablet; Adults and Geriatric Adults less than 75 years of age and weighing 60 kg or more: 60 mg PO as a loading dose, then 10 mg PO once daily. The optimal duration of therapy is not known. Also give aspirin 75 mg/day to 325 mg/day PO.
      • Prasugrel Oral tablet; Geriatric 75 years or older: Use in this population is generally not recommended, except in high-risk patients with a past history of myocardial infarction or diabetes, where studies have demonstrated benefit is greater than risk. In such patients, if weight is 60 kg or more: 60 mg PO as a loading dose, then 10 mg PO once daily. If weight is less than 60 kg: 60 mg PO as a loading dose, then consider a lower maintenance dose of 5 mg PO once daily. The optimal duration of therapy is not known. All patients should also take aspirin 75 mg/day to 325 mg/day PO.
      • Discontinue 7 days before elective coronary artery bypass graft surgery ^r1
    • Ticagrelor ^c151
      • Compared with clopidogrel
        • Greater antiplatelet effect with significant reduction in risk of thrombotic events compared with clopidogrel ^r36
        • Greater risk of bleeding compared with clopidogrel ^r37
        • Positive mortality benefit has been observed in non–ST-elevation myocardial infarction/unstable angina patients ^r1
      • Compared with prasugrel
        • Less myonecrosis was observed after percutaneous coronary intervention ^r38
        • In elderly or low-weight patients, a reduced dose of prasugrel compared with the standard dose of ticagrelor is associated with maintained anti-ischemic efficacy while protecting against excess risk for bleeding ^r35
      • Recommended, in the absence of contraindications, for all patients at moderate to high risk of ischemic events (eg, elevated cardiac troponin levels), regardless of initial treatment strategy and including those pretreated with clopidogrel (which should be discontinued when ticagrelor is started) ^r15
      • Ticagrelor Oral tablet; Adults: 180 mg PO loading dose plus aspirin (usually 325 mg PO) then, beginning 12 hours after loading dose, 90 mg PO twice daily plus aspirin 75 to 100 mg (i.e., 81 mg) PO once daily for 1 year. After 1 year, 60 mg PO twice daily and continue aspirin maintenance dose. Avoid maintenance doses of aspirin above 100 mg/day.
      • Discontinue 5 days before elective coronary artery bypass graft surgery and 24 hours before urgent coronary artery bypass graft surgery
    • Cangrelor ^c152
      • Reduced intraprocedural stent thrombosis compared with clopidogrel ^r39
      • Cangrelor Solution for injection; Adults: 30 mcg/kg single dose IV bolus followed immediately by 4 mcg/kg/minute continuous IV infusion. The bolus should be administered prior to PCI and the maintenance infusion should be continued for at least 2 hours or for the duration of PCI, whichever is longer. An oral P2Y12 platelet inhibitor (e.g., either ticagrelor, prasugrel or clopidogrel) should be administered to maintain platelet inhibition; choose one to administer. Prasugrel 60 mg PO or clopridogrel 600 mg PO may be administered after discontinuation of the cangrelor infusion. Do not administer prasugrel or clopidogrel prior to discontinuation of cangrelor. Ticagrelor 180 mg PO may be administered at any time during or immediately after discontinuation of cangrelor infusion.
    • Clopidogrel ^c153
      • For percutaneous coronary intervention
        • Clopidogrel Bisulfate Oral tablet; Adults: 300 or 600 mg PO once, within 24 hours and if more than 24 hours since fibrinolytic, respectively, followed by 75 mg PO once daily for at least 6 months in patients receiving a drug-eluting stent and at least 1 month in patients receiving a bare metal stent.
      • For medical management
        • Standard therapy for acute coronary syndromes before introduction of newer agents; relatively high rate of atherothrombotic events compared with newer agents, which conversely increase bleeding risk ^r36
        • Recommended for patients who cannot receive ticagrelor or prasugrel or who require oral anticoagulation ^r15
        • A 2020 trial suggested that, in patients aged 70 years or older presenting with non–ST-elevation acute coronary syndrome, clopidogrel is a favorable alternative, causing fewer bleeding events without an increase in the combined end point of all-cause death, myocardial infarction, stroke, and bleeding ^r40
        • Discontinue 5 days before elective coronary artery bypass graft surgery or 24 hours before urgent coronary artery bypass graft surgery ^r1
        • Clopidogrel Bisulfate Oral tablet; Adults: 300 mg PO once, followed by 75 mg PO once daily for up to 12 months.
  • Glycoprotein IIb/IIIa inhibitors ^c154
    • Reduced platelet aggregation through interruption of the final common pathway of fibrinogen-mediated cross-linkage of platelets; platelet counts need to be monitored during therapy
    • Used as bailout therapy when there is angiographic evidence of a large thrombus, slow or absent reperfusion, or other thrombotic complication; evidence is lacking ^r15r25
    • Eptifibatide ^c155
      • Eptifibatide Solution for injection; Adults: 180 mcg/kg (Max: 22.6 mg) IV bolus, followed by 2 mcg/kg/minute continuous IV infusion. Max: 15 mg/hour. Double-bolus eptifibatide (180 mcg/kg IV 10 minutes after first bolus) at the time of PCI in patients with intermediate/high-risk features is recommended. Continue the infusion until hospital discharge or initiation of CABG surgery, for up to 72 hours. If a patient is to undergo PCI, continue the infusion until hospital discharge or for up to 18 to 24 hours after the procedure, whichever comes first, allowing for up to 96 hours of therapy.
      • Discontinue 2 to 4 hours before coronary artery bypass graft surgery ^r1
    • Tirofiban ^r1c156
      • Tirofiban Hydrochloride Solution for injection; Adults: 25 mcg/kg IV within 5 minutes followed by 0.15 mcg/kg/minute for up to 18 to 24 hours at time of primary PCI. Discontinue at least 2 to 4 hours prior to urgent CABG.
• Anticoagulants ^c157
  • Choice of anticoagulant depends on timing of percutaneous intervention and individual thrombosis and bleeding risk
  • Parenteral agents used during initial management of acute coronary syndromes in combination with antiplatelet drugs
    • Unfractionated heparin ^c158
      • Indirect thrombin inhibitor
      • For ST-elevation myocardial infarction ^r2
        • Heparin Sodium (Porcine) Solution for injection; Adults: 60 units/kg IV bolus (Max: 4,000 units) given simultaneously with initial dose of thrombolytic therapy followed by heparin 12 units/kg/hour (Max: 1,000 units/hour) adjusted to keep the aPTT 1.5 to 2 times control (50 to 70 seconds) for 48 hours. All AMI patients without contraindications and who are not receiving heparin for another reason should receive not less than low-dose heparin (7,500 units subcutaneous every 12 hours) or LMWH until ambulation.
      • For non–ST-elevation myocardial infarction/unstable angina ^r1
        • Heparin Sodium (Porcine) Solution for injection; Adults: 60 units/kg (Max: 5,000 units) IV, then 12 units/kg/hour (Max: 1,000 units/hour) continuous IV infusion, initially. Titrate dose to target coagulation parameter to maintain therapeutic anticoagulation for 48 hours or until PCI performed.
    • Enoxaparin ^c159
      • Indirect thrombin inhibitor
      • More effective anticoagulant than unfractionated heparin, but carries a higher risk of bleeding ^r11r17
      • Enoxaparin Sodium (Porcine) Solution for injection; Adults: 1 mg/kg subcutaneous q12h with concurrent aspirin for at least 48 hours and until stable. Invasive strategies (e.g., PCI) are recommended; continue LMWH until PCI. In patients undergoing PCI, if last dose of enoxaparin was <= 8h before PCI, do not give additional anticoagulant treatment. If enoxaparin was given 8—12 hours before PCI, give enoxaparin 0.3 mg/kg IV or heparin prior to PCI; if enoxaparin was given >=12 hours before PCI, administer standard anticoagulant treatment during PCI.
      • Guidelines list as an option for non–ST-elevation myocardial infarction/unstable angina^r1 but not for ST-elevation myocardial infarction^r2
    • Fondaparinux ^c160
      • Factor Xa inhibitor ^c161
      • Used in combination with another anticoagulant in the setting of percutaneous coronary intervention owing to increased risk of catheter thrombosis
      • For ST-elevation myocardial infarction
        • Fondaparinux Sodium Solution for injection; Adults: Regimen suggested by OASIS-6 study. If no indication for heparin, give 2.5 mg subcutaneously once daily for 8 days or until hospital discharge; in patients with an indication for heparin (PCI, fibrinolysis, or receiving antithrombotics), give 2.5 mg IV† then 24 hours later begin 2.5 mg subcutaneously once daily for up to 7 days or until hospital discharge. Compared to heparin, fondaparinux reduces mortality without increasing the risk of bleeding in patients with STEMI not undergoing primary PCI.
      • For non–ST-elevation myocardial infarction/unstable angina
        • Fondaparinux Sodium Solution for injection; Adults: 2.5 mg subcutaneously once daily for 8 days or until hospital discharge; fondaparinux has been shown to be noninferior to enoxaparin with a decreased incidence of bleeding and death.
    • Bivalirudin ^c162
      • Direct thrombin inhibitor
      • Used only for patients undergoing percutaneous coronary intervention
      • Compared to heparin: ^r41
        • No significant difference in composite end point of death from any cause, myocardial infarction, or major bleeding at 180 days
        • No significant difference in the secondary end point of stent thrombosis
      • May be considered as an alternative for patients with contraindications to unfractionated heparin (ie, heparin-induced thrombocytopenia) who need anticoagulation ^r1
      • For ST-elevation myocardial infarction ^r2
        • Bivalirudin Solution for injection; Adults: 0.75 mg/kg IV bolus followed by 1.75 mg/kg/hour continuous IV infusion for duration of procedure. Perform ACT 5 minutes after bolus; may give additional 0.3 mg/kg IV bolus if needed.
      • For non–ST-elevation myocardial infarction/unstable angina
        • Dosing before percutaneous coronary intervention or diagnostic angiography ^r1
          • Bivalirudin Solution for injection; Adults: 0.1 mg/kg IV bolus followed by 0.25 mg/kg/hour continuous IV infusion until diagnostic angiography or PCI.
• Fibrinolytics
  • Pharmacologic reperfusion strategy indicated for patients with ST-elevation myocardial infarction and symptom onset within the past 12 hours for whom the time from first medical contact to anticipated time of percutaneous coronary intervention is 120 minutes or more ^c163
  • Administer within 30 minutes of hospital arrival
  • Streptokinase ^c164
    • Streptokinase Solution for injection; Adults: 1,500,000 International Units by IV infusion within 60 minutes.
  • Alteplase ^c165
    • Alteplase Solution for injection; Adults weighing 67 kg or less: 15 mg IV bolus, followed by 0.75 mg/kg IV over next 30 minutes, and then 0.5 mg/kg IV over the next 60 minutes.
    • Alteplase Solution for injection; Adults weighing more than 67 kg: 15 mg IV bolus, followed by 50 mg IV over next 30 minutes, and then 35 mg IV over the next 60 minutes.
  • Reteplase ^c166
    • Reteplase (Recombinant) Solution for injection; Adults: 10 units IV over 2 minutes followed by a second dose of 10 units IV 30 minutes after first dose.
  • Tenecteplase ^c167
    • Tenecteplase Solution for injection; Adults: Administer single bolus dose of 30 to 50 mg IV over 5 seconds based on patient weight (30 mg for less than 60 kg; 35 mg for 60 to 69 kg; 40 mg for 70 to 79 kg; 45 mg for 80 to 89 kg; or 50 mg for 90 kg or greater). Safety and efficacy have been primarily studied in AMI patients receiving aspirin and heparin. In the efficacy and safety trial, ASSENT 2, use of glycoprotein IIb/IIIa inhibitors was discouraged for the first 24 hours following randomization. Tenecteplase has been used with enoxaparin as an alternative to unfractionated heparin.
• β-blockers
  • Initiate oral β-blockers within 24 hours of presentation and continue indefinitely ^r1r2
  • IV β-blockers may be administered initially in patients with ST-elevation myocardial infarction who are hypertensive or who have ongoing ischemia; do not administer in patients at risk for shock ^r2
  • Preferred oral agents for patients with stabilized heart failure and reduced systolic function include metoprolol succinate, carvedilol, and bisoprolol ^r1
    • Metoprolol ^c168
      • Immediate-release dosing
        • Metoprolol Tartrate Oral tablet; Adults: 50 mg PO every 6 hours for 48 hours starting 15 minutes after the last IV dose. If the patient did not tolerate the full IV dose, initiate at 25 mg PO. The maintenance dose is 50 to 100 mg PO twice daily. In patients who were not candidates for metoprolol during the acute phase of the myocardial infarction, start 100 mg PO twice daily as soon as the patient is stable and without contraindications for use.
      • Once-daily dosing
        • Metoprolol Succinate Oral tablet, extended-release; Adults: Initially, 25 mg PO once daily in patients with NYHA class II heart failure or 12.5 mg PO once daily in patients with more severe heart failure. Double the dose every 2 weeks as tolerated, up to target dosage of 200 mg PO once daily.
    • Carvedilol ^c169
      • Carvedilol Oral tablet; Adults: Initially, 6.25 mg PO twice daily for 3 to 10 days. If tolerated (stable heart rate and blood pressure, minimal fluid retention), increase to 12.5 mg twice daily. Gradually titrate to target 25 mg twice daily, as tolerated. Max: 50 mg/day. If indicated, a lower starting dose of 3.125 mg PO twice daily may be used.
    • Bisoprolol ^c170
      • Bisoprolol Fumarate Oral tablet; Adults: Initially, 1.25 mg PO once daily for 48 hours, then 2.5 mg PO once daily for first month, then 5 mg PO once daily. Max: 10 mg PO once daily.
• Calcium channel blockers
  • Alternative to β-blockers for patients in whom β-blockers are contraindicated or not tolerated; used as an adjunct to β-blockers if the patient has continuing or recurrent ischemic symptoms ^r1r2
  • Verapamil and diltiazem are preferred nondihydropyridine calcium channel blockers; do not administer immediate-release nifedipine without concurrent use of a β-blocker ^r1
    • Verapamil ^c171
      • Verapamil Hydrochloride Oral tablet; Adults: Initially, 80 to 120 mg PO every 8 hours. May increase up to 480 mg/day, administered in 3 to 4 divided doses.
      • Verapamil Hydrochloride Oral tablet; Geriatric: Use lower initial adult dose (e.g., 40 mg PO every 8 hours).
    • Diltiazem ^c172
      • Diltiazem Hydrochloride Oral tablet; Adults: Initially, 30 to 60 mg PO 4 times per day. Increase up to 360 mg/day in 3 to 4 divided doses. Individual patients may respond to higher doses up to 480 mg/day.
• ACE inhibitors
  • Initiate ACE inhibitors within 24 hours of presentation and continue indefinitely, especially in patients with the following: ^r1r2
    • Pulmonary congestion ^c173
    • Heart failure ^c174
    • Anterior ST-elevation myocardial infarction ^c175
    • Left ventricular ejection fraction of 40% or less ^c176
    • Diabetes ^c177
    • Stable chronic kidney disease ^c178
  • Lisinopril ^c179
    • Lisinopril Oral tablet; Adults who are hemodynamically stable: Begin within 24 hours of symptom onset. Administer one 5 mg PO dose, followed by 5 mg PO after 24 hours, 10 mg PO after 48 hours, and then 10 mg PO once daily. If no complications or LV dysfunction by 6 weeks after AMI, ACEI can be stopped.
    • Lisinopril Oral tablet; Adults who develop low systolic blood pressure (<= 120 mmHg) either prior to therapy or during the first three days of therapy after the infarct: Begin within 24 hours of symptom onset. If hypotensive, start with 2.5 mg/day PO. If not hypotensive, 5 mg PO once daily may be given (reduce to 2.5 mg/day if needed). If SBP falls below 90 mm Hg for more than 1 hour, discontinue lisinopril.
    • Lisinopril Oral tablet; Geriatric: Start at the low end of adult dosage range.
  • Captopril ^c180
    • Captopril Oral tablet; Adults: 6.25 mg PO initially, followed 2 hours later with 12.5 mg PO, followed 10—12 hours later with 25 mg PO. Thereafter, 50 mg PO bid.
    • Captopril Oral tablet; Geriatric: See adult dosage. Initiate at low end of adult dosage range.
  • Ramipril ^c181
    • Ramipril Oral tablet; Adults: Initially, 1.25 mg to 2.5 mg PO once or twice daily. Increase dose as tolerated, adjusting to clinical response of patient up to Max: 10 mg/day.
  • Trandolapril ^c182
    • Trandolapril Oral tablet; Adults: Initially, 1 mg PO once daily. Increase dose as tolerated, adjusting to the clinical response of the patient up to 4 mg/day.
• Angiotensin receptor blockers
  • Alternative to ACE inhibitors for patients in whom ACE inhibitors are contraindicated or not tolerated ^r1r2
  • Valsartan ^c183
    • As effective as captopril (ACE inhibitor), but do not use these 2 agents together ^r11
    • Valsartan Oral tablet; Adults: 20 mg PO twice daily initially, started as early as 12 hours after a MI. May titrate within 7 days to 40 mg PO twice daily. Subsequently, titrate to target maintenance dose of 160 mg PO twice daily as tolerated. Consider dose reduction if hypotension or renal dysfunction occurs.
  • Losartan (off-label indication) ^c184
    • Losartan Potassium Oral tablet; Adults: Initially, 25 to 50 mg PO once daily. Increase dose as tolerated, adjusting to clinical response of patient up to Max: 50 to 150 mg/day.
• Aldosterone antagonists
  • Indicated as an adjunct for patients already on a β-blocker and an ACE inhibitor (or angiotensin receptor blocker) who have a left ventricular ejection fraction of 40% or less, diabetes, or heart failure ^r1
  • Spironolactone is a nonspecific aldosterone receptor antagonist and is associated with progestogenic and androgenic effects (eg, gynecomastia, erectile dysfunction, menstrual irregularities, hirsutism, mastalgia); eplerenone has lower affinity for androgen, progesterone, and glucocorticoid receptors and thus a lower incidence of these adverse effects.
  • Eplerenone ^c185
    • Eplerenone Oral tablet; Adults: Initially, 25 mg PO once daily. Increase dosage to 50 mg PO once daily as tolerated within 4 weeks. Coadministration of certain drugs may need to be avoided or dosage adjustments may be necessary; review drug interactions. Monitor serum potassium at baseline, within first week, and at 1 month after dosage initiation or adjustments; monitor more frequently in at-risk patients. If serum potassium 5.5 mEq/L or more, decrease dosage. Hold if serum potassium 6 mEq/L or more; may restart at 25 mg PO every other day once serum potassium less than 5.5 mEq/L.
  • Spironolactone ^c186
    • Spironolactone Oral tablet; Adults: Initially, 12.5 to 25 mg PO once daily. May reduce dosage to 25 mg PO every other day if hyperkalemia occurs with 25 mg PO once daily. May increase dosage to 50 mg/day, if clinically indicated and lower dose tolerated.
• Statins
  • Initiate (or continue) high-intensity statin therapy in all patients who do not have contraindications ^r1r2
  • It is recommended to start high-intensity statin therapy as early as possible, unless contraindicated, and to continue it as long-term maintenance ^r15
  • Atorvastatin and rosuvastatin are the only 2 statins with high-intensity therapy dosing. Atorvastatin 40 to 80 mg daily or rosuvastatin 20 to 40 mg daily is considered high-intensity dose. ^r30
  • Atorvastatin ^c187
    • Atorvastatin Calcium Oral tablet; Adults: 10 to 20 mg PO once daily. May start at 40 mg once daily for greater than 45% LDL-reduction. Range: 10 to 80 mg once daily.
  • Rosuvastatin ^c188
    • Rosuvastatin Calcium Oral tablet; Adults: Usual starting dose is 10 to 20 mg PO daily, with range of 5 to 40 mg PO daily. For Asian patients, consider starting dose of 5 mg once daily. JUPITER study used 20 mg PO once daily. Coadministration of certain drugs may need to be avoided or dosage adjustments may be necessary; review drug interactions.

Nondrug and supportive care

Initial supportive care includes oxygen therapy; therapeutic reperfusion includes coronary revascularization procedures (percutaneous coronary intervention or coronary artery bypass graft surgery) ^r1r2c189

• Oxygen therapy ^c190
  • Provide supplemental oxygen to patients who have arterial oxygen saturation of less than 90%, respiratory distress, or other evidence of hypoxemia ^r1

Risk reduction strategies for secondary prevention

• Cardiac rehabilitation ^c191
  • Refer all patients with acute coronary syndromes to a comprehensive outpatient cardiovascular rehabilitation program, either upon hospital discharge or at first follow-up office visit ^r1
  • Alternatively, a home-based cardiac rehabilitation program may be sufficient for low-risk patients
  • Aerobic exercise can begin 1 to 2 weeks after discharge for patients who have undergone percutaneous coronary intervention or coronary artery bypass graft surgery ^r1
  • Resistance exercise can begin 2 to 4 weeks after starting aerobic exercise ^r1
• Smoking cessation ^r26c192d10
  • Advise all patients to avoid exposure to tobacco smoke, including secondhand smoke; those who use tobacco should be advised to quit at each contact
    • Provide assistance in quitting through referral to a smoking cessation program and/or prescribing pharmacotherapy (eg, bupropion, varenicline)
• Nutrition ^c193
  • Modify nutrition counseling based on individual patient factors (eg, lipid profile, blood pressure, required caloric intake, alcohol intake)
  • Diets should emphasize nonstarchy vegetables, minimize added sugars and refined grains, and avoid highly processed foods; these diets are inherently relatively low in cholesterol ^r42r43r44
    • Mediterranean diet is often recommended; however, a 2019 Cochrane review found paucity of evidence for secondary prevention ^r45
    • DASH diet (Dietary Approaches to Stop Hypertension) is also recommended to reduce cardiovascular risk ^c194
  • Minimize intake of processed meats, refined carbohydrates, and sweetened beverages ^r42
  • Decrease intake of sodium, alcohol, and substitute healthy fats for saturated and trans fats ^{r26c195c196c197c198c199}
• Weight management ^c200
  • BMI goal is 18.5 to 24.9 kg/m²; waist circumference goal is less than 89 cm for females, less than 102 cm for males ^r26
  • If weight loss is required, initial weight loss goal should be 5% to 10% below baseline ^r26c201
• Physical activity
  • Before discharge from the acute care setting, provide the patient with instructions on specific activity recommendations (eg, lifting, stair climbing, housework, yardwork, sexual activity) ^c202
  • Perform risk assessment, including physical activity history and exercise test, before recommending exercise plan ^c203c204
  • Goal is 150 minutes of moderate-intensity aerobic activity per week (eg, 30-60 minutes on 5 days); supplement with resistance training at least twice per week ^r26r43
  • Counsel patients to report exercise-associated symptoms
• Prevention of infectious diseases ^r1
  • Pneumococcal vaccine is recommended for high-risk patients with cardiovascular disease and age older than 65 years ^c205
  • Yearly influenza vaccine is recommended for patients with cardiovascular disease ^c206

Comorbidities ^r1

• Hypertension ^c214c215
  • In patients with increased cardiovascular risk (including stable ischemic heart disease), reduction of systolic blood pressure to less than 130/80 mm Hg has been shown to reduce cardiovascular disease complications by 25% and all-cause mortality by 27% ^r52r53
  • In adults who have had a myocardial infarction or acute coronary syndrome, it is reasonable to continue β-blockers as long-term therapy for hypertension ^r52
• Dyslipidemia ^c216c217
  • Targeting specific lipid levels is controversial; use of intensive statin therapy, without specific goal direction, is recommended in all patients who can tolerate it ^r30
  • Reduce LDL-C by at least 50% with high-intensity statin therapy or maximally tolerated statin therapy ^r30
    • In very-high-risk atherosclerotic cardiovascular disease, use an LDL-C threshold of 70 mg/dL to consider addition of nonstatins to statin therapy
    • Very high risk includes:
      • History of at least multiple major atherosclerotic cardiovascular events or history of 1 major atherosclerotic cardiovascular event and multiple high-risk conditions
    • Reasonable to add ezetimibe to maximally tolerated statin therapy when LDL-C level remains at 70 mg/dL or higher
    • Patients at very high risk whose LDL-C level remains at 70 mg/dL or higher on maximally tolerated statin and ezetimibe therapy, adding a PCSK9 inhibitor is reasonable, although long-term safety (longer than 3 years) is uncertain
• Diabetes ^c218
  • Aggressively control blood glucose levels and maintain at 180 mg/dL or less while avoiding hypoglycemia ^r1
  • Most patients with type 2 diabetes and coronary artery disease should be treated with an oral glucose-lowering agent proven to reduce major cardiovascular events and/or cardiovascular mortality, either a sodium-glucose cotransporter 2 inhibitor or a glucagonlike peptide 1 receptor agonist ^r54
  • Strongest evidence for cardiovascular benefit has been demonstrated with liraglutide, dulaglutide, semaglutide, empagliflozin, dapagliflozin, and canagliflozin ^r54
  • May be commenced at during admission, or at discharge or outpatient follow-up
• Heart failure ^c219
  • May complicate diagnosis, because troponin levels may be elevated owing to acute heart failure
  • Base revascularization strategy on the extent of coronary artery disease, cardiac lesions, left ventricular dysfunction, and prior revascularization ^r1
  • In the presence of a large area of ischemia or significant heart failure, a percutaneous ventricular assist device or an intra-aortic balloon pump may be needed during surgical intervention ^r1
• Chronic kidney disease ^c220
  • Adjust pharmacotherapy dosages according to creatinine clearance in patients with chronic kidney disease
  • Provide adequate hydration to patients undergoing angiography ^r1

Special populations

• Older patients (aged 75 years or older) ^r1
  • Adjust pharmacotherapy dosages according to weight and/or creatinine clearance in older patients
  • Tailor care to consider patient preferences and goals, functional and cognitive status, comorbidities, drug interactions, and life expectancy
  • Survival advantage associated with an early invasive strategy in patients with non–ST-elevation myocardial infarction is also seen in patients aged 80 years and older ^r55
• Females ^r1
  • Consider adjusting antiplatelet and anticoagulant dosages according to weight and/or creatinine clearance to reduce the risk of bleeding
  • Pregnant patients may undergo myocardial revascularization if ischemia-guided therapy is ineffective
  • Do not use an early invasive strategy to manage females with non–ST-elevation myocardial infarction/unstable angina and low-risk assessment (eg, low TIMI score, troponin levels within the reference range), because risk of harm outweighs likely benefit ^r1
• Patients acutely intoxicated with cocaine or methamphetamine ^r1
  • β-blockers are contraindicated owing to risk of coronary spasm
  • Benzodiazepines may be used alone or with nitroglycerin to manage hypertension and tachycardia associated with cocaine or methamphetamine intoxication

At-risk populations

• Populations at risk for coronary artery disease (and acute coronary syndromes) ^r1r2
  • Advanced age (65 years or older) ^{c261c262c263c264c265c266c267c268c269}
  • Male sex ^{c270c271c272c273c274c275c276c277c278}
  • Family history of coronary artery disease (or acute coronary syndromes) ^{c279c280c281c282c283c284c285c286c287}
  • Type 2 diabetes ^{c288c289c290c291c292c293c294c295c296}
  • Hypertension ^{c297c298c299c300c301c302c303c304c305}
  • Renal insufficiency ^{c306c307c308c309c310c311c312c313c314}
  • Prior myocardial infarction ^{c315c316c317c318c319c320c321c322c323}
  • Prior coronary revascularization ^{c324c325c326c327c328c329c330c331c332}
  • Use of antineoplastic and immunosuppressive therapies ^{c333c334c335c336c337c338c339c340c341c342c343c344}
  • Smoking history ^{c345c346c347c348c349c350c351c352c353c354}

Screening tests

• Global risk tools are used to estimate risk of experiencing a coronary heart disease event over a specific period (often 10 years) ^r42
  • For adults aged 40 to 75 years, assess traditional cardiovascular risk factors routinely; for adults aged 20 to 39 years, it is reasonable to assess traditional risk factors at least every 4 to 6 years ^r42
    • American Heart Association's web-based calculator^r57c355
    • Framingham Risk Score ^r42c356
    • Systematic Coronary Risk Evaluation ^r42r58c357
  • Risk categories include the following: low (less than 5%), borderline (5% to less than 7.5%), intermediate (7.5% or higher to less than 20%), or high (20% or higher) 10-year risk ^r42
  • Decisions about specific interventions (eg, statin treatment and its intensity) are based on this category
  • For patients with intermediate predicted risk or for select adults with borderline predicted risk, coronary artery calcium measurement can be a useful tool in refining risk assessment for statin therapy ^c358