DR Medhat MRCP

'A' wave = Atrial contraction
Large (Giant) if ↑ atrial pressure e.g. tricuspid stenosis, pulmonary stenosis,
pulmonary hypertension.
Absent if in atrial fibrillation.
Cannon 'a' waves
Caused by atrial contractions against a closed tricuspid valve
Regular Cannon `a` waves :
- V.Tach (with 1:1 A-V conduction )
- A-V nodal reentry tachycardia (AVNRT
- Single chamber ventricular pacing.
Irregular cannon `a` waves : complete heart block
'C' wave
Closure of triCuspid valve
Not normally visible
'X' descent = relaXation of RT atrium & fall in atrial pressure during ventricular systole
'V' wave
Due to passive filling of blood into the atrium against a closed tricuspid valve
Giant v waves in tricuspid regurgitation
'Y' descent = opening of tricuspid valve (absent in cardiac tamponade).
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