EKG Common

Common EKG

Infarction pattern

STEMI

ST Elevated Criteria for STEMI (วัดที่ J point)

≥ 1 ใน 2 leads ที่ติดกัน
V2 - V3
- Male
  - < 40 ปี : ≥ 2.5 mm
  - ≥ 40 ปี : ≥ 2.0 mm

ประเภทของ STEMI

Inferior wall STEMI (II,III,aVF ~ I,aVL)
Anterior wall STEMI (V2-5)
Antero septal wall STEMI (V1-4)
Antero lateral wall STEMI (V3-6,I avL)
Posterior wall STEMI
Lateral wall STEMI (I,aVL,V5,V6 - II,III,aVF)
Septal wall STEMI (V1,V2)
Inferior wall STEMI + RV infarction (V2R-V6R)
- ดังนั้นถ้าพบว่าเป็น inferior wall จึงต้องทำ V2R V3R ทุกราย (โดยเฉพาะ STE in lead III ที่ยกสูงกว่่าใน lead II)
- เกิดจาก Rt. ventricular branch of Rt.coronary artery
Inferior wall STEMI + Posterior wall MI (V7-V8-V9 -V12)
- ทำเมื่อมี ST depression ใน anterior leads
- เกิดจาก Posterior descending branch of Rt.coronary artery

NSTEMI

T depression มี 3 แบบคือ

Horizontal ST depression
Downsloping ST depression
Upsloping ST depression

** แบบที่เกี่ยวกับ MI คือ Horizontal และ downsloping ส่วน unsloping คิดถึง NSTEMI น้อยครับ

LV Aneurysm

STE ที่เกิดขึ้นหลังจาก 2 wk นับจากหลังเกิด Acute MI
มักพบใน precordial leads
อาจจะเป็น concave(ยิ้ม) หรือ convex(บึ้ง) ก็ได้
มี well-formed Q หรือ QS wave
T wave invert จะเล็กๆ (ไม่เหมือนใน acute MI ที่จะมี hyperacute T ที่ตัวสูงๆ)

COMMON CAUSE

Acute myocardial infarction (by far the most common).
Cardiomyopathy
Cardiac infection
Congenital abnormalities

ตัวอย่าง EKG

Deep Q waves in V1-3 with markedly reduced R wave height in V4.
Residual ST elevation in V1-3 (“left ventricular aneurysm” morphology).
Biphasic/inverted T waves in V1-5.
Poor R wave progression (R wave height < 3mm in V3).
Abnormal Q waves and T-wave inversion in I and aVL.
The pattern indicates prior infarction of the anteroseptal and lateral walls

รูป 2 (วงกลม)เป็น acute เพราะ T wave ยกสูง

LMCA occlusion : STE in aVR

Typical ECG findings with LMCA occlusion:

Widespread horizontal ST depression, most prominent in leads I, II and V4-6
ST elevation in aVR ≥ 1mm
ST elevation in aVR ≥ V1

Differential diagnosis

Proximal left anterior descending artery (LAD) occlusion
Severe triple-vessel disease (3VD)
Diffuse subendocardial ischaemia e.g. due to
- O2 supply/demand mismatch following resuscitation from cardiac arrest

LMCA Mimics

SVT (AVNRT)
Atrial flutter

De Winter T Waves (anterior STEMI โดยไม่มี STE)

Key diagnostic features

ST depression and Peaked!! T waves in the precordial leads. (~2% of acute LAD occlusions)

Diagnostic Criteria

Tall, prominent, symmetric T waves in the precordial leads
Upsloping ST segment depression >1mm at the J-point in the precordial leads
Absence of ST elevation in the precordial leads
ST segment elevation (0.5mm-1mm) in aVR
“Normal” STEMI morphology may precede or follow the deWinter pattern

Wellens syndrome

a pattern of

Deeply inverted or
Biphasic T waves in V2-3

Specific for = critical stenosis of the LAD artery
Patients may be pain free or have normally or minimally elevated cardiac enzymes however, they are = high risk for extensive anterior wall MI within the next few days to weeks.

Dx Criteria

Deeply-inverted or biphasic T waves in V2-3 (may extend to V1-6)
Isoelectric or minimally-elevated ST segment (< 1mm)
No precordial Q waves
Preserved precordial R wave progression
Recent history of angina
ECG pattern present in pain-free state
Normal or slightly elevated serum cardiac markers

Ref. https://litfl.com/wellens-syndrome-ecg-library/

Non-infarction pattern

Acute Pulmonary Embolism

ECG changes associated with acute pulmonary embolism may be seen in any condition that causes acute pulmonary hypertension

Dilation of the right atrium and right ventricle with consequent shift in the position of the heart.
Right ventricular ischaemia.
Increased stimulation of the sympathetic nervous system due to pain, anxiety and hypoxia.

Key ECG findings include

Sinus tachycardia
Complete or incomplete RBBB
Right ventricular strain pattern
- T wave inversions in the right precordial leads (V1-4) ± the inferior leads (II, III, aVF)
- This pattern is seen in up to 34% of patients and is associated with high pulmonary artery pressures.
Right axis deviation
Dominant R wave in V1 – a manifestation of acute right ventricular dilatation.
Right atrial enlargement (P pulmonale) – peaked P wave in lead II > 2.5 mm
S_I Q_III T_III pattern deep S wave in lead I, Q wave in III, inverted T wave in III. This “classic” finding is neither sensitive nor specific for pulmonary embolism; found in only 20% of patients with PE.
Clockwise rotation – shift of the R/S transition point towards V6 with a persistent S wave in V6 (“pulmonary disease pattern”), implying rotation of the heart due to right ventricular dilatation.
Atrial tachyarrhythmias – AF, flutter, atrial tachycardia. Seen in 8% of patients.
Non-specific ST segment and T wave changes, including ST elevation and depression. Reported in up to 50% of patients with PE.

Ultrasonography may be useful in differentiating the two (ACS and PE)

Example

Right bundle branch block (RBBB) : RSR'

Diagnostic Criteria

Broad QRS > 120 ms
RSR’ pattern in V1-3 (‘M-shaped’ QRS complex)
Wide, slurred S wave in the lateral leads (I, aVL, V5-6)

Incomplete RBBB

= RSR’ pattern in V1-3 with QRS duration < 120 ms.

ระวัง Brugada syndrome

Left bundle branch block (LBBB)

QRS duration of > 120 ms
Dominant S wave in V1
Broad monophasic R wave in lateral leads (I, aVL, V5-V6)
Absence of Q waves in lateral leads (I, V5-V6; small Q waves are still allowed in aVL)
Prolonged R wave peak time > 60ms in left precordial leads (V5-6)

Causes of Left Bundle Branch Block

Aortic stenosis
Ischaemic heart disease
Hypertension
Dilated cardiomyopathy
Anterior MI
Primary degenerative disease (fibrosis) of the conducting system (Lenegre disease)
Hyperkalaemia
Digoxin toxicity

LV hypertrophy

Sokolow + Lyon
- S V1+ R V5 or V6 > 35 mm

Cornell criteria (Circulation, 1987;3: 565-72)
- S V3 + R avl > 28 mm in men
- S V3 + R avl > 20 mm in women

Framingham criteria (Circulation,1990; 81:815-820)
- R avl > 11mm, R V4-6 > 25mm
- S V1-3 > 25 mm, S V1 or V2 +
- R V5 or V6 > 35 mm, R I + S III > 25 mm