ACUTE MYOCARDIAL
INFARCTION - AN OVERVIEW
Dr Jain T. Kallarakkal MD, FRCP, DM
Consultant Interventional Cardiologist
What is acute M I ?
Acute coronary syndrome (ACS)
Umbrella term for the clinical signs and
symptoms of myocardial ischemia:
 Unstable angina
...
Unstable




angina

Occurs at rest and usually lasting >20
minutes
New onset angina that limits activity
Increasing an...
W H O Diagnosis of Myocardial Infarction
(MI) Requires ≥ 2 of the Following:
1) Prolonged ischemic-type chest discomfort

...
STEMI
 STEMI

is a clinical syndrome defined
by characteristic symptoms of
myocardial ischemia in association
with persis...
STEMI




Diagnostic ST elevation in the absence of
left ventricular (LV) hypertrophy or left
bundle-branch block (LBBB)...
Ischemic-Type Chest Pain
 Pressure

sensation, fullness or squeezing
retro-sternally
 Radiation of chest pain into the
j...
Other Symptoms
 Diaphoresis
 Syncope

or sweating

or near-syncope

 Impairment

other cause

of cognitive function wit...
ECG



ST-segment elevation (with compatible history)
specificity=91%, sensitivity=46%
The higher the elevation and the ...
Other causes of ST-segment
elevation
 Pericarditis



Old MI (aneurysm)

 Normal

variant (early repolarization)
ECG- ACUTE INFERO
POSTERIOR MI
ECG – ACUTE AWMI
CKMB


More specific for cardiac muscle than total
CK



Rises and falls slightly earlier than total CK



Should be co...
Troponins T and I


Very sensitive and specific



Similar early rise in serum levels as CK-MB
(2-4 hours) but stays ele...
Serum Markers in ACS
First
Detectable

Peak

Duration

Troponin I

2-4 hrs

10-24 hrs

5-10 days

Troponin T

2-4 hrs

10-...
Pathogenesis
 Platelet aggregation
 Thrombus formation
 Vasospasm

Plaque rupture
(55-80%)

Incomplete occlusion
Distal...
Time is Muscle
HISTORY:1969-79 CCU ERA
MORTALITY 15%
1980-89 LYTIC THERAPY
MORTALITY 6.5 TO 7%
Acute Management of MI: General
Measures
1) Oxygen

by nasal prongs for 2-3 hours
2) Bed rest with bed side commode for 12...
Analgesic – Morphine Sulfate
Good dose response, easily reversible; 2-5mg
every 5-30 min (sometimes >30mg)
 Peripheral ve...







Aspirin 162 to 325 mg should be given before primary PCI
After PCI, aspirin should be continued indefinitely
Lo...
Statins
 Prognosis

improved even in post-MI
with “normal” cholesterol level

 Aggressive

approach to lipid control
(go...
Nitroglycerin (NTG)






NTG given initially if systolic blood pressure
>90 mm hg
Avoid long-acting nitrates initiall...
NTG (continued)


Dosage – 5-100 μg/min, start with 5-10
μg/min and increase every 5 to 10 min



Nitrate tolerance afte...
NTG Side Effects


Headache – quite common



Hypotension – avoid in RV infarction



Hypoxemia from V/Q mismatch – nee...


Patients with STEMI undergoing reperfusion with
fibrinolytic therapy should receive anticoagulant therapy
for a minimum...




UFH administered as a weight-adjusted
intravenous bolus and infusion to obtain an
activated partial thromboplastin t...


Fondaparinux administered with initial
intravenous dose, followed in 24 hours by
daily subcutaneous injections if the
e...
Beta Blockers






↓ mortality evident by day 1
Quickly reversed by isoproterenol
Safe
Ideal candidates – early pres...


Oral beta blockers should be initiated in the
first 24 hours in patients with STEMI who
do not have signs of HF, eviden...




contraindicated if PR interval more than
0.24 seconds, second- or third-degree
heart block, active asthma, or reacti...
Ace Inhibitors


Definite indication – within 24 hours of moderate
or large anterior MI’s or MI’s associated with CHF
or ...
Reperfusion by Thrombolysis


Indications
• ST elevation

• Left bundle branch block (obscuring
STsegment analysis)
• MI ...
Reperfusion by Thrombolysis
(continued)
 Controversial

potential contraindications:
• Patients >75 years old
• Late pres...


Clear contraindications:
• CVA/TIA within one year (avoidance of
stroke)
• Hemorrhagic CVA at any time
• Intracranial n...
Absolute contraindications








Any prior ICH
Known structural cerebral vascular lesion (e.g.,
arteriovenous malf...







Active bleeding or bleeding diathesis (excluding
menses)
Significant closed-head or facial trauma within
3 mo
...
Relative contraindications






History of chronic, severe, poorly controlled
hypertension
Significant hypertension ...







Major surgery (<3 wk)
Recent (within 2 to 4 wk) internal bleeding
Noncompressible vascular punctures
Pregnanc...
Fibrinolytic Agent




Fibrin-specific:
Tenecteplase (TNK-tPA)
Reteplase (rPA)
Alteplase (tPA)
Non–fibrin-specific:
Stre...
Choice of Thrombolytic Agent
(continued)


90 minute patency better with rt-PA than SK



Patency at 24 hours roughly eq...
Thrombolytics: Bottom Line
 Choose

tPA for large MI’s presenting

early
 tPA in patients who have previously
received s...
Angioplasty after thrombolysis





Immediate transfer for cardiogenic shock or
severe acute HF irrespective of time de...
Class I:
Objective evidence for recurrent
infarction or ischemia (rescue PCI).
(Level of evidence: B)
Class IIa:
Cardiogenic Shock or hemodynamic
instability.
(Level of evidence: B)


Class I:
1. Spontaneous or provocable myocardial
ischemia during recovery from
infarction.
(Level of evidence: C)
2. Pe...
Reperfusion by Primary PTCA
 Percutaneous

coronary intervention is an
alternative therapy to fibrinolysis
 Performed
by...
Primary PCI in STEMI





Ischemic symptoms <12 h
Contraindications to fibrinolytic therapy
irrespective of time delay...
CATHLAB
Guidelines


Class I Recommendation
within 30 minutes or that door-to-balloon
(or medical contact–to-balloon) time for
PC...
Thrombolysis


Class I Recommendations
STEMI patients presenting to a facility
without the capability for expert, prompt
...
Reperfusion by Primary PTCA Conclusion
 If

quickly available in a good quality
center, PTCA is a superior alternative to...
ACC/AHA

STEMI

Guidelines:

Primary Percutaneous Coronary Intervention


Class I Recommendations



If immediately avai...


Class I Recommendations



Level of Evidence: B


Primary PCI should be performed as quickly as possible (goal of
med...
THANK YOU
Acute coronary syndrome
Acute coronary syndrome
Acute coronary syndrome
Acute coronary syndrome
Acute coronary syndrome
Acute coronary syndrome
Acute coronary syndrome
Acute coronary syndrome
Upcoming SlideShare
Loading in...5
×

Acute coronary syndrome

1,036

Published on

Acute coronary syndrome for medical students

Published in: Education, Health & Medicine
0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,036
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
90
Comments
0
Likes
3
Embeds 0
No embeds

No notes for slide

Acute coronary syndrome

  1. 1. ACUTE MYOCARDIAL INFARCTION - AN OVERVIEW Dr Jain T. Kallarakkal MD, FRCP, DM Consultant Interventional Cardiologist
  2. 2. What is acute M I ?
  3. 3. Acute coronary syndrome (ACS) Umbrella term for the clinical signs and symptoms of myocardial ischemia:  Unstable angina  Non–ST-segment elevation myocardial infarction  ST-segment elevation myocardial infarction. 
  4. 4. Unstable    angina Occurs at rest and usually lasting >20 minutes New onset angina that limits activity Increasing angina: Pain that occurs more frequently, lasts longer periods or is increasingly limiting the patients activity
  5. 5. W H O Diagnosis of Myocardial Infarction (MI) Requires ≥ 2 of the Following: 1) Prolonged ischemic-type chest discomfort 2) Serial electrocardiogram (ECG) changes 3) Rise and fall of serum cardiac markers
  6. 6. STEMI  STEMI is a clinical syndrome defined by characteristic symptoms of myocardial ischemia in association with persistent electrocardiographic (ECG) ST elevation and subsequent release of biomarkers of myocardial necrosis.
  7. 7. STEMI   Diagnostic ST elevation in the absence of left ventricular (LV) hypertrophy or left bundle-branch block (LBBB) ST elevation at the J point in at least 2 contiguous leads of ≥2 mm (0.2 mV) in men or ≥1.5 mm (0.15 mV) in women in leads V2–V3and/or of ≥1 mm (0.1 mV) in other contiguous chest leads or the limb leads
  8. 8. Ischemic-Type Chest Pain  Pressure sensation, fullness or squeezing retro-sternally  Radiation of chest pain into the jaw/teeth, shoulder, arm, and/or back  Associated dyspnea or shortness of breath  Associated epigastric discomfort with or without nausea and vomiting
  9. 9. Other Symptoms  Diaphoresis  Syncope or sweating or near-syncope  Impairment other cause of cognitive function without
  10. 10. ECG   ST-segment elevation (with compatible history) specificity=91%, sensitivity=46% The higher the elevation and the more the leads involved, the larger the infarct and the greater the mortality
  11. 11. Other causes of ST-segment elevation  Pericarditis  Old MI (aneurysm)  Normal variant (early repolarization)
  12. 12. ECG- ACUTE INFERO POSTERIOR MI
  13. 13. ECG – ACUTE AWMI
  14. 14. CKMB  More specific for cardiac muscle than total CK  Rises and falls slightly earlier than total CK  Should be considered the current standard for diagnosing MI
  15. 15. Troponins T and I  Very sensitive and specific  Similar early rise in serum levels as CK-MB (2-4 hours) but stays elevated longer (10-14 days)  Worse prognosis
  16. 16. Serum Markers in ACS First Detectable Peak Duration Troponin I 2-4 hrs 10-24 hrs 5-10 days Troponin T 2-4 hrs 10-24 hrs 5-14 days CK-MB 3-4 hrs 10-24 hrs 2-4 days MBIsoforms 2-4 hrs 6-12 hrs 0.5-1 days
  17. 17. Pathogenesis  Platelet aggregation  Thrombus formation  Vasospasm Plaque rupture (55-80%) Incomplete occlusion Distal embolization Unstable angina NSTE MI Exertion BP, HR Vasoconstriction Vulnerable Plaque Complete occlusion STEMI
  18. 18. Time is Muscle
  19. 19. HISTORY:1969-79 CCU ERA MORTALITY 15%
  20. 20. 1980-89 LYTIC THERAPY MORTALITY 6.5 TO 7%
  21. 21. Acute Management of MI: General Measures 1) Oxygen by nasal prongs for 2-3 hours 2) Bed rest with bed side commode for 12 hours (longer if unstable); avoid constipation and Valsalva maneuver 3) ECG monitoring 4) Analgesics
  22. 22. Analgesic – Morphine Sulfate Good dose response, easily reversible; 2-5mg every 5-30 min (sometimes >30mg)  Peripheral venous and arterial dilation; blocks sympathetic efferent discharge at CNS level; reduces preload and afterload – good with CHF  Side effects - hypotension and bradycardia occur rarely; respiratory depression with severe COPD 
  23. 23.     Aspirin 162 to 325 mg should be given before primary PCI After PCI, aspirin should be continued indefinitely Loading dose of a P2Y12receptor inhibitor. Options include Clopidogrel 600 mg; or Prasugrel 60 mg; or Ticagrelor 180 mg 4P2Y12inhibitor therapy should be given for 1 year who receive a stent in maintenance doses:Clopidogrel 75 mg daily; or Prasugrel 10 mg daily; or Ticagrelor 90 mg twice a day
  24. 24. Statins  Prognosis improved even in post-MI with “normal” cholesterol level  Aggressive approach to lipid control (goal LDL<100) mandatory for all patients with acute M I
  25. 25. Nitroglycerin (NTG)     NTG given initially if systolic blood pressure >90 mm hg Avoid long-acting nitrates initially Pain in acute MI is due to continued ischemia so NTG may be rational choice for ongoing ischemic pain Helpful in pulmonary edema
  26. 26. NTG (continued)  Dosage – 5-100 μg/min, start with 5-10 μg/min and increase every 5 to 10 min  Nitrate tolerance after > 24 hours  Recommend routinely for most MI’s for 24 – 48 hours (particularly with CHF), hypertension or recurrent ischemia)
  27. 27. NTG Side Effects  Headache – quite common  Hypotension – avoid in RV infarction  Hypoxemia from V/Q mismatch – need to be alert for this phenomenon
  28. 28.  Patients with STEMI undergoing reperfusion with fibrinolytic therapy should receive anticoagulant therapy for a minimum of 48 hours, and preferably for the duration of the index hospitalization, up to 8 days or until revascularization if performed
  29. 29.   UFH administered as a weight-adjusted intravenous bolus and infusion to obtain an activated partial thromboplastin time of 1.5 to 2.0 times control, for 48 hours or until revascularization; Enoxaparin administered according to age, weight, and creatinine clearance, given as an intravenous bolus, followed in 15 minutes by subcutaneous injection
  30. 30.  Fondaparinux administered with initial intravenous dose, followed in 24 hours by daily subcutaneous injections if the estimated creatinine clearance is greater than 30 mL/min, for the duration of the index hospitalization, up to 8 days or until revascularization
  31. 31. Beta Blockers      ↓ mortality evident by day 1 Quickly reversed by isoproterenol Safe Ideal candidates – early presentation, ↑HR, ↑BP, anterior MI Contraindications – HR<60, BP<100, moderate/severe CHF, AV block, bad COPD
  32. 32.  Oral beta blockers should be initiated in the first 24 hours in patients with STEMI who do not have signs of HF, evidence of a low output state, increased risk for cardiogenic shock age >70 years, systolic BP <120 mm Hg, sinus tachycardia >110 bpm or heart rate <60 bpm, and increased time since onset of symptoms of STEMI.
  33. 33.   contraindicated if PR interval more than 0.24 seconds, second- or third-degree heart block, active asthma, or reactive airways disease) Patients with initial contraindications to the use of beta blockers in the first 24 hours after STEMI should be reevaluated to determine their subsequent eligibility.
  34. 34. Ace Inhibitors  Definite indication – within 24 hours of moderate or large anterior MI’s or MI’s associated with CHF or EF < 40%  Controversial indication – all MI’s within first 24 hours, stopped in 4-6 weeks if no CHF or significant left ventricular dysfunction (EF<40%)evident
  35. 35. Reperfusion by Thrombolysis  Indications • ST elevation • Left bundle branch block (obscuring STsegment analysis) • MI <12 hours since onset
  36. 36. Reperfusion by Thrombolysis (continued)  Controversial potential contraindications: • Patients >75 years old • Late presentations (12-24 hours) • Hypertension (>180/100 mmHg)
  37. 37.  Clear contraindications: • CVA/TIA within one year (avoidance of stroke) • Hemorrhagic CVA at any time • Intracranial neoplasm • Active internal bleeding (not include menses) • Suspected aortic dissection
  38. 38. Absolute contraindications       Any prior ICH Known structural cerebral vascular lesion (e.g., arteriovenous malformation) Known malignant intracranial neoplasm (primary or metastatic) Ischemic stroke within 3 mo EXCEPT acute ischemic stroke within 4.5 h Suspected aortic dissection
  39. 39.      Active bleeding or bleeding diathesis (excluding menses) Significant closed-head or facial trauma within 3 mo Intracranial or intraspinal surgery within 2 mo Severe uncontrolled hypertension (unresponsive to emergency therapy) For streptokinase, prior treatment within the previous 6 mo
  40. 40. Relative contraindications      History of chronic, severe, poorly controlled hypertension Significant hypertension on presentation (SBP >180 mm Hg or DBP >110 mm Hg) History of prior ischemic stroke >3 mo Dementia Known intracranial pathology not covered in absolute contraindications
  41. 41.       Major surgery (<3 wk) Recent (within 2 to 4 wk) internal bleeding Noncompressible vascular punctures Pregnancy Active peptic ulcer Oral anticoagulant therapy
  42. 42. Fibrinolytic Agent   Fibrin-specific: Tenecteplase (TNK-tPA) Reteplase (rPA) Alteplase (tPA) Non–fibrin-specific: Streptokinase
  43. 43. Choice of Thrombolytic Agent (continued)  90 minute patency better with rt-PA than SK  Patency at 24 hours roughly equal between tPA and SK
  44. 44. Thrombolytics: Bottom Line  Choose tPA for large MI’s presenting early  tPA in patients who have previously received streptokinase  Choose streptokinase if cost is a factor
  45. 45. Angioplasty after thrombolysis    Immediate transfer for cardiogenic shock or severe acute HF irrespective of time delay from MI onset Urgent transfer for failed reperfusion or reocclusion As part of an invasive strategy in stable patients with PCI between 3 and 24 h after successful fibrinolysis
  46. 46. Class I: Objective evidence for recurrent infarction or ischemia (rescue PCI). (Level of evidence: B)
  47. 47. Class IIa: Cardiogenic Shock or hemodynamic instability. (Level of evidence: B)
  48. 48.  Class I: 1. Spontaneous or provocable myocardial ischemia during recovery from infarction. (Level of evidence: C) 2. Persistent hemodynamic instability. (Level of evidence: C)
  49. 49. Reperfusion by Primary PTCA  Percutaneous coronary intervention is an alternative therapy to fibrinolysis  Performed by a skilled operator supported by experienced personnel  Performed in a well-equipped catheterization laboratory
  50. 50. Primary PCI in STEMI     Ischemic symptoms <12 h Contraindications to fibrinolytic therapy irrespective of time delay Cardiogenic shock or acute severe HF Evidence of ongoing ischemia 12 to 24 h
  51. 51. CATHLAB
  52. 52. Guidelines  Class I Recommendation within 30 minutes or that door-to-balloon (or medical contact–to-balloon) time for PCI can be kept within 90 minutes.
  53. 53. Thrombolysis  Class I Recommendations 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)
  54. 54. Reperfusion by Primary PTCA Conclusion  If quickly available in a good quality center, PTCA is a superior alternative to thrombolysis, especially in high-risk patients presenting early or in patients where thrombolytics are contraindicated
  55. 55. ACC/AHA STEMI Guidelines: Primary Percutaneous Coronary Intervention  Class I Recommendations  If immediately available, primary PCI should be performed:  In patients with STEMI (including true posterior MI) or MI with new or presumably new LBBB within 12 hours of symptom onset;  In a timely fashion (balloon inflation within 90 minutes);  By persons skilled in the procedure (>75 PCI procedures per year).  The procedure should be supported by:  Experienced personnel;  An appropriate laboratory environment (> 200 PCI procedures per year, of which > 36 are primary PCI for STEMI); and  Cardiac surgery backup. (Level of Evidence: A)
  56. 56.  Class I Recommendations  Level of Evidence: B  Primary PCI should be performed as quickly as possible (goal of medical contact-to-balloon or door-to-balloon time < 90 minutes).  If the symptom duration is within 3 hours and the expected door-to-balloon time minus the expected door-to-needle time is:    Within 1 hour, primary PCI is generally preferred. Greater than 1 hour, fibrinolytic therapy (fibrin-specific agents) is generally preferred. If symptom duration is greater than 3 hours, primary PCI is generally preferred
  57. 57. THANK YOU
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×