ECGbook.com

Making Medical Education Free for All

ECGbook.com

Making Medical Education Free for All

Home /

Inferior STEMI Infarction

Inferior STEMI infarction

Coronary Artery Dominance

Coronary artery dominance, posterior descending artery (PDA), Right-dominant

Coronary artery dominance, posterior descending artery (PDA), Left-dominant
  • Right coronary artery dominance
    • 70% of people have a dominant right coronary artery
    • RIP originates from the right coronary artery
  • Left coronary artery dominance
    • 10% of people have a dominant left coronary artery
    • RIP originates from the left coronary artery
  • Coronary artery codominance
    • 20% of people have codominance
    • RIP originates from both the left and right coronary arteries
  • Wraparound of the apex
    • 0.1% of people have a wraparound of the apex
    • RIA wraps around the apex of the heart and continues as RIP to the inferior wall
Coronary artery dominance, posterior descending artery (PDA), Co-dominant

Coronary artery dominance, posterior descending artery (PDA), Wrap-around

Inferior Wall Myocardial Infarction

Inferior Wall STEMI (ST Segment Elevation Myocardial Infarction), LAD culprit artery

ECG and Inferior Wall STEMI

ECG inferior ST elevation (II, III, aVF) and reciprocal ST depression (I, aVL)

Dynamics of ST Elevation in STEMI

ECG STEMI ST elevation evolution, acute, subacute, chronic infarction stage

STEMI Stages by Phase


Occlusion of the Right Coronary Artery

Right coronary culprit artery, inferior STEMI, STEMI right ventricle
  • 80% of inferior wall infarctions
    • Are due to occlusion of the dominant right coronary artery
  • The dominant right coronary artery supplies
    • The right part of the posterior wall
    • The medial part of the inferior wall
    • The inferior part of the septum
  • 40% of inferior wall infarctions also have right ventricular infarction
    • Occlusion of the right coronary artery (RCA) must be proximal
    • Distal occlusion of the RCA will result in an isolated inferior wall infarction

ECG and Occlusion of the Dominant RCA

ECG Isolated inferior STEMI infarction, Occlusion distal dominant right coronary artery, RCA culprit artery

Occlusion of the Left Coronary Artery (LCx)

Inferior STEMI, occlusion dominant left circumflex artery (LCx)
  • 18% of inferior wall infarctions
    • Are due to occlusion of the dominant left circumflex artery (LCx)
  • The dominant left coronary artery supplies (via LCx)
    • The lateral part of the inferior wall
    • The posterior wall
    • The basal part of the left ventricle

  • Proximal occlusion of the circumflex artery (LCx) leads to:
  • LCx artery supplies an area of the myocardium that is
    • poorly monitored by 12-lead ECG
    • Sometimes referred to as the silent ECG LCx area

ECG and Occlusion of the Dominant LCx (Left Circumflex Artery)

ECG inferior STEMI with posterior - lateral STEMI, left coronary artery dominance, Proximal LCx culprit artery

Occlusion of the RIA in "Wraparound"

Culprit wraparound artery, Inferior STEMI and Anterior STEMI
  • Wraparound Apex
    • 0.1% of people
    • The RIA wraps around the apex of the heart and continues as the RIP to the inferior wall
  • In the case of RIA occlusion, the infarction will be:
    • Anterior Wall (ST Elevations V2-V4)
    • Inferior Wall (ST Elevations II, III, aVF)

  • It is a very rare situation
  • ST elevations will not be prominent
    • because the leads for the anterior and inferior walls are partially contralateral
    • Vectors for the anterior and inferior walls are partially directed away from each other


Occlusion of distal Right coronary artery, inferior STEMI, STEMI right ventricle
ECG inferior STEMI infarction, ST elevation in inferior leads (II, III, aVF), occlusion dominant right coronary artery, pathologic Q wave

Subacute Inferior STEMI



Old inferior STEMI infarction
ECG old inferior infarction, pathologic Q wave in inferior leads (II, III, aVF)

Old Inferior STEMI

  • Sinus Rhythm
  • Pathological Q Wave (II, III, aVF)
    • Without ST Elevations (II, III, aVF)
  • Negative T Waves (III, aVF)
  • Indicates old inferior wall infarction
    • Pathological Q is most commonly associated with STEMI
    • Rarely, pathological Q can also occur with NSTEMI


Right coronary culprit artery, inferior STEMI, STEMI right ventricle
ECG acute inferior STEMI and acute right ventricular STEMI infarction, proximal right coronary artery occlusion

Acute Inferior STEMI and Right Ventricular STEMI



Right coronary culprit artery, inferior STEMI, STEMI right ventricle
ECG acute inferior and posterior STEMI, proximal right coronary artery occlusion

Acute Inferior and Posterior STEMI

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF) (V5-V6)
    • ST Elevation III > II
  • Posterior STEMI
  • Indicates proximal occlusion of the dominant right coronary artery
    • The right coronary artery may supply the posterior wall as well as the apex of the left ventricle


Right coronary culprit artery, inferior STEMI, right ventricle STEMI
ECG acute inferior and posterior infarction, proximal right coronary artery occlusion (culprit artery - vessel)

Acute Inferior and Posterior STEMI



Culprit wraparound artery, Inferior STEMI and Anterior STEMI
ECG acute inferior and anterior infarction, occlusion wraparound artery

Acute Anterior and Inferior STEMI (Wraparound)

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF)
    • ST Elevation III > II
  • ST Depressions V1-V3
  • However, the patient had a "wraparound" artery on coronary angiography
    • Resulted in infarctions of both anterior and inferior walls
    • However, the inferior wall is more extensive
      • Thus, the vector points more towards the inferior wall
      • Hence, ST depressions are observed in V1-V3
  • Indicates a "wrap-around" RCA artery occlusion
Coronary catheterization, coronary angiogram, wraparound artery

Coronary Angiography

  • A: Distal RCA Occlusion
  • B: Distal RCA After Recanalization

  • Distal RCA wraps around the apex
    • Indicates a wraparound artery
    • Found in approximately 0.1% of people


Right coronary culprit artery, inferior STEMI, STEMI right ventricle
ECG acute inferior and right ventricular STEMI, coronary angiogram proximal occlusion right coronary artery

Acute Inferior STEMI and Right Ventricular STEMI




Sources

  • ECG from Basics to Essentials Step by Step
  • litfl.com
  • ecgwaves.com
  • metealpaslan.com
  • medmastery.com
  • uptodate.com
  • ecgpedia.org
  • wikipedia.org
  • Strong Medicine
  • Understanding Pacemakers





šípka späť

Home /

Inferior STEMI Infarction

Inferior STEMI infarction

Coronary Artery Dominance

  • The anterior wall is supplied by ramus interventricularis anterior (RIA)
  • The inferior wall is supplied by ramus interventricularis posterior (RIP)
  • Right coronary artery dominance
    • 70% of people have a dominant right coronary artery
    • RIP originates from the right coronary artery
  • Left coronary artery dominance
    • 10% of people have a dominant left coronary artery
    • RIP originates from the left coronary artery
  • Coronary artery codominance
    • 20% of people have codominance
    • RIP originates from both the left and right coronary arteries
  • Wraparound of the apex
    • 0.1% of people have a wraparound of the apex
    • RIA wraps around the apex of the heart and continues as RIP to the inferior wall



Coronary artery dominance, posterior descending artery (PDA), Wrap-around

Coronary artery dominance, posterior descending artery (PDA), Left-dominant Coronary artery dominance, posterior descending artery (PDA), Right-dominant Coronary artery dominance, posterior descending artery (PDA), Co-dominant

Inferior Wall Myocardial Infarction

  • Occurs due to occlusion of the RIP
    • RIP is most commonly the branch of the right coronary artery
  • Accounts for 50% of all myocardial infarctions
  • 40% of inferior wall infarctions also have right ventricular infarction
    • Due to the dominance of the right coronary artery (70% of people)
  • 20% of inferior infarctions have
  • Location of the inferior infarction depends on
  • Dominant right coronary artery supplies
    • The right part of the posterior wall
    • The medial part of the inferior wall
    • The inferior part of the septum
  • Dominant left coronary artery supplies (via RCx)
    • The lateral part of the inferior wall
    • The posterior wall
    • The basal part of the left ventricle


Inferior Wall STEMI (ST Segment Elevation Myocardial Infarction), LAD culprit artery

ECG and Inferior Wall STEMI
ECG inferior ST elevation (II, III, aVF) and reciprocal ST depression (I, aVL)

Dynamics of ST Elevation in STEMI

ECG STEMI ST elevation evolution, acute, subacute, chronic infarction stage

STEMI Stages by Phase


Occlusion of the Right Coronary Artery

  • 80% of inferior wall infarctions
    • Are due to occlusion of the dominant right coronary artery
  • The dominant right coronary artery supplies
    • The right part of the posterior wall
    • The medial part of the inferior wall
    • The inferior part of the septum
  • 40% of inferior wall infarctions also have right ventricular infarction
    • Occlusion of the right coronary artery (RCA) must be proximal
    • Distal occlusion of the RCA will result in an isolated inferior wall infarction
Right coronary culprit artery, inferior STEMI, STEMI right ventricle

ECG and Occlusion of the Dominant RCA
ECG Isolated inferior STEMI infarction, Occlusion distal dominant right coronary artery, RCA culprit artery

Occlusion of the Left Coronary Artery (LCx)

  • 18% of inferior wall infarctions
    • Are due to occlusion of the dominant left circumflex artery (LCx)
  • The dominant left coronary artery supplies (via LCx)
    • The lateral part of the inferior wall
    • The posterior wall
    • The basal part of the left ventricle

  • Proximal occlusion of the circumflex artery (LCx) leads to:
  • LCx artery supplies an area of the myocardium that is
    • poorly monitored by 12-lead ECG
    • Sometimes referred to as the silent ECG LCx area

Inferior STEMI, occlusion dominant left circumflex artery (LCx)

ECG and Occlusion of the Dominant LCx (Left Circumflex Artery)

  • In the case of occlusion of the LCx in the dominant left coronary artery (LCx)
  • ECG and Inferior Wall Infarction (Distal LCx Occlusion)
    • ST Elevations (II, III, aVF)
      • Elevation II ≥ III
    • Reciprocal ST Depression (aVR)

  • ECG and Inferior + Lateral + Posterior Infarction (Proximal LCx Occlusion)
    • Inferior Wall Infarction
      • ST Elevations (II, III, aVF)
        • Elevation II ≥ III
      • Reciprocal ST Depression (aVR)
    • Lateral Infarction
      • ST Elevations (V5-V6, I, aVL)
    • Posterior Infarction
      • Reciprocal ST Depression (V1-V3)
      • ST Elevations (V7-V9)
ECG inferior STEMI with posterior - lateral STEMI, left coronary artery dominance, Proximal LCx culprit artery

Occlusion of the RIA in "Wraparound"

  • Wraparound Apex
    • 0.1% of people
    • The RIA wraps around the apex of the heart and continues as the RIP to the inferior wall
  • In the case of RIA occlusion, the infarction will be:
    • Anterior Wall (ST Elevations V2-V4)
    • Inferior Wall (ST Elevations II, III, aVF)

  • It is a very rare situation
  • ST elevations will not be prominent
    • because the leads for the anterior and inferior walls are partially contralateral
    • Vectors for the anterior and inferior walls are partially directed away from each other

Culprit wraparound artery, Inferior STEMI and Anterior STEMI


ECG inferior STEMI infarction, ST elevation in inferior leads (II, III, aVF), occlusion dominant right coronary artery, pathologic Q wave

Subacute Inferior STEMI

 Occlusion of distal Right coronary artery, inferior STEMI, STEMI right ventricle


ECG old inferior infarction, pathologic Q wave in inferior leads (II, III, aVF)

Old Inferior STEMI

  • Sinus Rhythm
  • Pathological Q Wave (II, III, aVF)
    • Without ST Elevations (II, III, aVF)
  • Negative T Waves (III, aVF)
  • Indicates old inferior wall infarction
    • Pathological Q is most commonly associated with STEMI
    • Rarely, pathological Q can also occur with NSTEMI
 Old inferior STEMI infarction


ECG acute inferior STEMI and acute right ventricular STEMI infarction, proximal right coronary artery occlusion

Acute Inferior STEMI and Right Ventricular STEMI

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF)
    • Significant Reciprocal ST Depressions (I, aVL)
  • Right Ventricular STEMI
  • Indicates proximal occlusion of the dominant right coronary artery
 Right coronary culprit artery, inferior STEMI, STEMI right ventricle


ECG acute inferior and posterior STEMI, proximal right coronary artery occlusion

Acute Inferior and Posterior STEMI

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF) (V5-V6)
    • ST Elevation III > II
  • Posterior STEMI
  • Indicates proximal occlusion of the dominant right coronary artery
    • The right coronary artery may supply the posterior wall as well as the apex of the left ventricle
 Right coronary culprit artery, inferior STEMI, STEMI right ventricle


ECG acute inferior and posterior infarction, proximal right coronary artery occlusion (culprit artery - vessel)

Acute Inferior and Posterior STEMI

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF)
    • ST Elevation III > II
  • Posterior STEMI
    • ST Depressions V1-V3
    • Apply posterior leads V7-V9 to the patient
  • Indicates proximal occlusion of the dominant right coronary artery
 Right coronary culprit artery, inferior STEMI, right ventricle STEMI


ECG acute inferior and anterior infarction, occlusion wraparound artery

Acute Anterior and Inferior STEMI (Wraparound)

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF)
    • ST Elevation III > II
  • ST Depressions V1-V3
  • However, the patient had a "wraparound" artery on coronary angiography
    • Resulted in infarctions of both anterior and inferior walls
    • However, the inferior wall is more extensive
      • Thus, the vector points more towards the inferior wall
      • Hence, ST depressions are observed in V1-V3
  • Indicates a "wrap-around" RCA artery occlusion
 Culprit wraparound artery, Inferior STEMI and Anterior STEMI

Coronary catheterization, coronary angiogram, wraparound artery

Coronary Angiography

  • A: Distal RCA Occlusion
  • B: Distal RCA After Recanalization

  • Distal RCA wraps around the apex
    • Indicates a wraparound artery
    • Found in approximately 0.1% of people


ECG acute inferior and right ventricular STEMI, coronary angiogram proximal occlusion right coronary artery

Acute Inferior STEMI and Right Ventricular STEMI

  • Sinus Rhythm
  • Inferior STEMI
    • ST Elevations (II, III, aVF)
    • ST Elevation III > II
    • Significant Reciprocal ST Depressions (I, aVL)
  • Right Ventricular STEMI
  • On coronary angiography, there was
    • proximal occlusion of the dominant right coronary artery (RCA)
 Right coronary culprit artery, inferior STEMI, STEMI right ventricle



Sources

  • ECG from Basics to Essentials Step by Step
  • litfl.com
  • ecgwaves.com
  • metealpaslan.com
  • medmastery.com
  • uptodate.com
  • ecgpedia.org
  • wikipedia.org
  • Strong Medicine
  • Understanding Pacemakers