ECGbook.com

Making Medical Education Free for All

ECGbook.com

Making Medical Education Free for All

Home /

Atrial Myocardial Infarction

Atrial myocardial infarction (ischemia), Ta wave elevation and depression, Atrial Ischemia, Atrial Injury

Atrial Depolarization and Repolarization

P Ta wave, atrial depolarization, repolarization, atrial electrical vectors
  • Atrial Depolarization (Dep.)
    • It proceeds from the endocardium (Endo) to the epicardium (Epi)
    • Vector (+) points towards the epicardium (towards the corresponding lead)
    • Produces a P wave
  • Atrial Repolarization (Rep.)
    • It proceeds from the epicardium to the endocardium (similarly)
      • In the atrial myocardium, the action potential has the same duration everywhere
    • Vector (+) points towards the endocardium (opposite direction)
    • Produces a wide, flat, or negative Ta wave

Ta Wave

ECG atrial depolarization P wave

ECG atrial repolarization Ta wave

Atrial Infarction

atrial ischemia, infarction
  • The atria are hemodynamically insignificant compared to the ventricles
    • An isolated atrial infarction does not cause hemodynamic changes
    • Often occurs simultaneously with a ventricular infarction
    • 10% of ventricular infarctions also involve atrial infarction
  • Often manifests as
  • Incidence of atrial infarction is:
    • 85% right atrium
    • 10% biatrial infarction
    • 5% left atrium

PQ (PTa) Segment

ECG PQ, PR, PTa, PTp segment

ECG and Atrial Infarction

  • Based on ECG, it is not possible to differentiate between atrial infarction and ischemia
atrial ischemia (infarction) PQ elevation, PQ depression. Liu criteria
  • Evaluate the PQ segment:
    • PQ elevation > 0.5mm (V5, V6) and reciprocal PQ depression (V1, V2)
    • PQ elevation > 0.5mm (I) and reciprocal PQ depression (II, III)
    • PQ depression > 1.5mm in precordial leads (V1-V6)
    • PQ depression > 1.2mm (I, II, III) and supraventricular arrhythmia

  • Right Atrial Infarction:
    • PQ depression (II, III, aVF) > 1.2mm
    • PQ elevation (aVR, V1)

Evaluation of the PQ Segment

ECG PT segment PQ segment depression measurement

PQ Depression (1mm)



ECG PQ depression P wave and PQ segment measurement

PQ Depression (2mm)


Pericarditis and Atrial Infarction

  • Pericarditis has
  • Atrial Infarction
    • PQ depressions > 1.2mm (not across the entire heart)
    • Without concave ST elevations

ECG pericarditis vs. atrial ischaemia, infarction

Atrial Infarction

  • PQ depression 1mm
  • Criteria suggest 1.2mm, which is difficult to measure in practice
  • ST segment is on the isoelectric line
    • ST segment is measured relative to the TP segment

ECG pericarditis vs atrial ischaemia infarction, PQ depression, concave ST elevation

Pericarditis

  • PQ depression 0.5mm
    • Usually in every lead except (aVR, V1)
  • Concave ST elevation


ECG right atrial infarction and inferior STEMI, PQ (PR) elevation, PQ (PR) depression

Right Atrial Infarction and Inferior Wall STEMI



ECG acute pericarditis, concave ST elevation, PQ (PR) depression

Acute Pericarditis



ECG atrial ischaemia infarction and inferior infarction STEMI

Right Atrial Infarction and STEMI of the Inferior Wall



ECG right atrial and inferior ventricular STEMI infarction.

Right Atrial Infarction and STEMI of the Inferior Wall

  • Elevations and depressions are assessed relative to the "end" of the P wave
  • STEMI of the Inferior Wall
  • Right Atrial Infarction
    • PQ depression (II, III, aVF)
    • Infarction and ischemia of the atria cannot be differentiated by EKG


ECG atrial ischaemia (infarction) and atril fibrillation

Atrial Infarction and Atrial Fibrillation




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 /

Atrial Myocardial Infarction

Atrial myocardial infarction (ischemia), Ta wave elevation and depression, Atrial Ischemia, Atrial Injury

Atrial Depolarization and Repolarization


P Ta wave, atrial depolarization, repolarization, atrial electrical vectors
  • Atrial Depolarization (Dep.)
    • It proceeds from the endocardium (Endo) to the epicardium (Epi)
    • Vector (+) points towards the epicardium (towards the corresponding lead)
    • Produces a P wave
  • Atrial Repolarization (Rep.)
    • It proceeds from the epicardium to the endocardium (similarly)
      • In the atrial myocardium, the action potential has the same duration everywhere
    • Vector (+) points towards the endocardium (opposite direction)
    • Produces a wide, flat, or negative Ta wave

Ta Wave

  • Represents repolarization of the atria
  • The atrial myocardium is narrow
    • Therefore, it has a small amplitude, sometimes none
  • It is most commonly isoelectric
    • Sometimes it is flat-negative (< 2mm)
  • It is covered by the QRS complex

  • It deepens in cases of:
    • Atrial ischemia/infarction
      • In infarction, elevations of the Ta wave may also occur
    • Sinus tachycardia due to increased sympathetic tone
      • Without atrial ischemia
  • Shortens in cases of:
ECG atrial depolarization P wave

ECG atrial repolarization Ta wave

Atrial Infarction

  • The atria are hemodynamically insignificant compared to the ventricles
    • An isolated atrial infarction does not cause hemodynamic changes
    • Often occurs simultaneously with a ventricular infarction
    • 10% of ventricular infarctions also involve atrial infarction
  • Often manifests as
  • Incidence of atrial infarction is:
    • 85% right atrium
    • 10% biatrial infarction
    • 5% left atrium

atrial ischemia, infarction

PQ (PTa) Segment

  • Infarction and ischemia of the atria are manifested on the Ta wave
    • Most commonly as deep depression, rarely as elevation of the Ta wave
    • The Ta wave in infarction is evaluated in the area of the PQ segment
  • PQ Segment
    • It is the segment between the end of the P wave and the beginning of the QRS
    • Sometimes referred to as: PR, PTa, PTp segment

  • The atrial myocardium is thin
    • Therefore, changes in infarction (ischemia) of the atria are minimal
    • Results in PQ elevations and PQ depressions
    • Changes persist for approximately 4 hours after infarction
ECG PQ, PR, PTa, PTp segment

ECG and Atrial Infarction

  • Based on ECG, it is not possible to differentiate between atrial infarction and ischemia

  • Evaluate the PQ segment:
    • PQ elevation > 0.5mm (V5, V6) and reciprocal PQ depression (V1, V2)
    • PQ elevation > 0.5mm (I) and reciprocal PQ depression (II, III)
    • PQ depression > 1.5mm in precordial leads (V1-V6)
    • PQ depression > 1.2mm (I, II, III) and supraventricular arrhythmia

  • Right Atrial Infarction:
    • PQ depression (II, III, aVF) > 1.2mm
    • PQ elevation (aVR, V1)
 atrial ischemia (infarction) PQ elevation, PQ depression. Liu criteria

Evaluation of the PQ Segment

ECG PT segment PQ segment depression measurement

PQ Depression (1mm)

  • PQ is measured relative to the TP segment
  • TP segment is
    • Between the end of the T wave and the beginning of the P wave
 ECG PQ depression P wave and PQ segment measurement

PQ Depression (2mm)

  • If the TP segment is not present
  • Then we "estimate" the end of the P wave

Pericarditis and Atrial Infarction

  • Pericarditis has
  • Atrial Infarction
    • PQ depressions > 1.2mm (not across the entire heart)
    • Without concave ST elevations

ECG pericarditis vs. atrial ischaemia, infarction

Atrial Infarction

  • PQ depression 1mm
  • Criteria suggest 1.2mm, which is difficult to measure in practice
  • ST segment is on the isoelectric line
    • ST segment is measured relative to the TP segment
 ECG pericarditis vs atrial ischaemia infarction, PQ depression, concave ST elevation

Pericarditis

  • PQ depression 0.5mm
    • Usually in every lead except (aVR, V1)
  • Concave ST elevation


ECG right atrial infarction and inferior STEMI, PQ (PR) elevation, PQ (PR) depression

Right Atrial Infarction and Inferior Wall STEMI



ECG acute pericarditis, concave ST elevation, PQ (PR) depression

Acute Pericarditis



ECG atrial ischaemia infarction and inferior infarction STEMI

Right Atrial Infarction and STEMI of the Inferior Wall



ECG right atrial and inferior ventricular STEMI infarction.

Right Atrial Infarction and STEMI of the Inferior Wall

  • Elevations and depressions are assessed relative to the "end" of the P wave
  • STEMI of the Inferior Wall
  • Right Atrial Infarction
    • PQ depression (II, III, aVF)
    • Infarction and ischemia of the atria cannot be differentiated by EKG


ECG atrial ischaemia (infarction) and atril fibrillation

Atrial Infarction and Atrial Fibrillation




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