Jugular venous Pulse/Pressure ( part 2)

Jugular venous Pulse(part 2)

Normal JVP waves

 

1st image: Imagine you put a ball(green ball) in IJV blood coloumn. The ball have pointer in its end. The pointer is connected with a paper. So if the ball moves upward that denotes pressure(blood coloumn in IJV) raise and the pointer will draw ascend wave in paper. If the  ball moves downward that denotes pressure fall and the pointer will draw descend wave in paper.
2nd image : now ill tell the cardiac event that produces different waves of JVP .
        There are 5 waves. a, c ,x descend,v and y descend.
        As JVP is related with right heart we are going to concentrate on right chambers and tricuspid valve.

a wave : 
Atrium -  atrial systole. Contraction of atrium will produce the back pressure (due to devoid of valves)in superior vena cava thereby produce elevation of blood coloumn in IJV . The ball will move up and produce ascending wave that is "a" wave.
Tricuspid valve - opened .blood from atrium draining into ventricle during atrial systole.
Ventricle - ventricular Diastole. It recieves blood from atrium.
 x descend :
Atrium - atrial diastole starts. Blood from superior and inferior vena cava drained into atrium. So the blood column in IJV falls. The ball will move down and produces descending wave.
Tricuspid valve - closed.
Ventricle - ventricular diastole.
c wave : (* inbetween a and x wave)
Atrium-  atrial diastole. 
Tricuspid valve - closed but produces little jerk towards atrium due to onset of ventricular systole in this phase. That jerk will produce c wave.
Ventricle- venticular systole starts.
v wave : 
Atrium -  atrial diastole. Atrium fully filled with blood. Eventhough there is dilation of atrium no space for filling. So the blood starts rising in IJV and ball moves upward. V wave is produced.
Tricuspid valve- closed. 
Ventricle- ventricle continues its systole.
y descend : 
Atrium - atrial diastole. It acts as a Pipe between vena cavas and ventricle because of opened tricuspid valve.
Tricuspid valve- opened . Blood from vena cava filled directly into ventricle.(refer diagram) so the blood coloumn in IJV falls. Ball will descend .
Ventricle- ventricular diastole starts.

 Note: onset of systole and diastole of both atrium and ventricle below the diagram.