Diastolic augmentation
Unassisted systolic
pressure
Assisted systolic pressure
Dicrotic Notch
Unassisted diastolic pressure
Assisted diastolic pressure
Without
augmentation
With 1:2 augmentation
Diastolic Augmentation
Dicrotic Notch
Early inflation will increase afterload as the heart must eject
blood against an inflated balloon. This inturn will result in
increased myocardial wall stress and Left ventricular end
diastolic pressure thereby increasing left ventricular work,
reducing cardiac output.
Diastolic augmentationUnassisted systolic pressure
Delayed inflation of the balloon after aortic valve closure results in inadequate
diastolic
Augmentation. There is blunting or complete lack of diastolic augmentation
waveform.
Associated with this is a lack of end-diastolic pressure decrease ( afterload
reduction) and no increase in diastolic perfusion pressure. There is a prolonged
dip or U wave then a blunted or decreased diastolic augmentation
Assisted and unassisted
Systolic pressure
Diastolic augmentation
Tracing reveals a normal diastolic augmentation but then a long drawn out
U-shaped wave prior to the assisted systolic waveform . There is inadequate
preload reduction and therefore no change in assisted and unassisted systolic pressure.
Diastolic augmentation
Assisted systolic pressure
Unassisted systolic pressure
Assisted end - diastolic pressure
Unassisted end-diastolic pressure
Late deflation of IABP causes a dramatic increase in afterload as systole begins with higher
intra-aortic pressure. This causes late opening of the aortic valve and severely reduces the
cardiac output. The pressure wave form reveals an assisted end-diastolic pressure that is higher
than the unassisted end-diastolic pressure and a drastically reduced assisted systolic pressure.