ecg-3

rhythm

normal aka sinus rhythm

• P wave precedes QRS wave
• therefore,num of P wave equals with QRS wave
• PR intervals-normal

sinus rhythm

sinus tachycardia

• rate:fast(300/3=100 beats per minute)
• the rest normal
  
  

  sinus tachycardia

P wave

• wide and bifid P wave-in left atrial hypertrophy(might be due to mitral stenosis)
  
• peak/tall P wave-in right atrial hypertrophy(might be due to tricuspid valve stenosis)

QRS wave

normal

i.its duration is no greater than 0.12 sec

ii.In a right ventricular lead (V1) the S wave is greater than the R wave
iii.In left ventricular leads (V5 or V6) the height of R wave is less than 25mm
iv.Left ventricular leads may show Q waves due to septal depolarization, but these are less than 1mm across and less than 2mm deep
v.R in V6 plus S in V1 less than 35mm

right ventricular hypertrophy

-tall R wave in V1 and deep S-wave in V6

left ventricular hypertrophy
-deep S wave in V1 and tall R wave in V6