effects of endovascular treatment of thoracic aortic diseases on aortic hemodynamics

Effects of endovascular treatment of thoracic aortic

diseases on aortic hemodynamics

UNIFESP

Diego Gaia MD PhDdrgaia@uol.com.br

Diego Gaia MD PhDdrgaia@uol.com.br

Input impedance: in practice ?

Z = P/Q

time (s)0.0 0.2 0.4 0.6 0.8

blo

od

pre

ssu

re (

mm

Hg

)

70

80

90

100

110

120

time (s)0.0 0.2 0.4 0.6 0.8 1.080

100

120

140

160young subject (C-type) old subject (A-type)

contribution of reflected wave

contribution of reflected wave

measured pressure

measured pressure

Wave reflection

• explains patho-physiological changes in blood pressure

• early return of reflected wave: ‘boost’ of systolic pressure

• extra load on the heart

• What is the influence of aortic prosthesis / stent-graft placement ?

Type B / DTA

PWV / Impedance / PP / Aix / Reflexion

• Day before• During procedure

• 1 PO• 7 PO

• 30 PO• 60 PO

• 180 PO• 360 PO

Pulse tonometry

Flow: Echocardiogram

Pressure and flow: before and after endoprosthesis deployment

Before After

Pressure:

Flow:

time (s)0.0 0.2 0.4 0.6 0.8

blo

od

pre

ssu

re (

mm

Hg

)

70

80

90

100

110

120

time (s)0.0 0.2 0.4 0.6 0.8 1.080

100

120

140

160young subject (C-type) old subject (A-type)

contribution of reflected wave

contribution of reflected wave

measured pressure

measured pressure

Type B Dissections

23 %

34 %

DTA

Pulse Wave Velocity – Femoral / Carotid

20 %

Conclusions

• Aortic stiffness MACE

• Stent-graft can increase aortic stifness and left ventricular afterload (Impedance/PWV)

• Negative cardiovascular impact

• Device improvementos – compliance / stiffness