The Normal Abnormal ECG Waveforms All Limb Leads
The Normal & Abnormal ECG
Waveforms
All Limb Leads
Lead Placement a. VF
EKG Distributions n n n Anteroseptal: V 1, V 2, V 3, V 4 Anterior: V 1–V 4 Anterolateral: V 4–V 6, I, a. VL Lateral: I and a. VL Inferior: II, III, and a. VF Inferolateral: II, III, a. VF, and V 5 and V 6
Rhythm n Sinus n n n Originating from SA node P wave before every QRS P wave in same direction as QRS
What is this rhythm? Normal sinus rhythm
What is the heart rate? www. uptodate. com 300 / 6 = 50 bpm 1500 / 30 = 50
The QRS Axis § Represents the overall direction of the heart’s activity § Axis of – 30 to +90 degrees is normal
The Quadrant Approach n QRS up in I and up in a. VF = Normal
Normal Intervals n PR n n QRS n n 0. 20 sec (less than one large box) 0. 08 – 0. 10 sec (1 -2 small boxes) QT n n n 450 ms in men, 460 ms in women Based on sex / heart rate Half the R-R interval with normal HR
RHYTHEM n n HR : Bradycardia or tachycardia Pause Premature beat blocks
What is this rhythm?
What is this rhythm?
Premature Atrial Contractions Trigeminy pattern
What is this rhythm?
What is this rhythm?
Tachyarrhythmia Regular n Narrow QRS n Wide QRS = VT or SVT +aberrancy Irregular- irregular n AF n MAT
Supraventricular Tachycardia Retrograde P waves Narrow complex, regular; retrograde P waves, rate <220
Ventricular Tachycardia
What is this rhythm?
What is this rhythm?
What is this rhythm?
What is this rhythm?
What is this rhythm?
What is this rhythm?
Accelerated Idioventricular Ventricular escape rhythm, 40 -110 bpm Seen in AMI, a marker of reperfusion
Junctional Rhythm Rate 40 -60, no p waves, narrow complex QRS
AV- Blocks n AV blocks n First degree block n n Second degree block, Mobitz type 1 n n PR gradually lengthened, then drop QRS Second degree block, Mobitz type 2 n n PR interval fixed and > 0. 2 sec PR fixed, but drop QRS randomly Type 3 block n PR and QRS dissociated
What is this rhythm? First degree AV block PR is fixed and longer than 0. 2 sec
What is this rhythm?
First Degree Heart Block PR interval >200 ms
What is this rhythm? Type 1 second degree block (Wenckebach)
What is this rhythm?
First Degree Heart Block, Mobitz Type I (Wenckebach) PR progressively lengthens until QRS drops
What is this rhythm? Type 2 second degree AV block
What is this rhythm?
Second Degree Heart Block, Mobitz Type II PR interval fixed, QRS dropped intermittently
What is this rhythm? 3 rd degree heart block (complete)
What is this rhythm?
Bundle branch block n RBBB n LBBB
Left Bundle Branch Block Monophasic R wave in I and V 6, QRS > 0. 12 sec Loss of R wave in precordial leads QRS T wave discordance I, V 1, V 6 Consider cardiac ischemia if a new finding
Right Bundle Branch Block V 1: RSR prime pattern with inverted T wave V 6: Wide deep slurred S wave
Ischemia & MI
What do you see in this EKG? ST depression II, III, a. VF, V 3 -V 6 = ischemia
What is the diagnosis? Acute inferior MI with ST elevation in leads II, III, a. VF
Wellen’s Sign ST elevation and biphasic T wave in V 2 and V 3 Sign of large proximal LAD lesion
Lateral MI Reciprocal changes
Inferolateral MI ST elevation II, III, a. VF ST depression in a. VL, V 1 -V 3 are reciprocal changes
Anterolateral / Inferior Ischemia LVH, AV junctional rhythm, bradycardia
Right Ventricular Myocardial Infarction Found in 1/3 of patients with inferior MI Increased morbidity and mortality ST elevation in V 4 -V 6 of Right-sided EKG
Hyperkalemia Tall, narrow and symmetric T waves
Brugada Syndrome RBBB or incomplete RBBB in V 1 -V 3 with convex ST elevation
Atrial Flutter with Variable Block Sawtooth waves Typically at HR of 150
Torsades de Pointes Notice twisting pattern Treatment: Magnesium 2 grams IV
Digitalis Dubin, 4 th ed. 1989
Prolonged QT QT > 450 ms Inferior and anterolateral ischemia
Acute Pulmonary Embolism SIQIIITIII in 10 -15% T-wave inversions, especially occurring in inferior and anteroseptal simultaneously RAD
Wolff-Parkinson-White Syndrome Short PR interval <0. 12 sec Prolonged QRS >0. 10 sec Delta wave Can simulate ventricular hypertrophy, BBB and previous MI
- Slides: 63