Larry J. Diaz, MD, FACC, FSCAI, FAHA, FSVM, FACP Director, Endovascular & Vascular Medicine Fellowship

Metro Health Hospital Assistant Professor of Medicine

Michigan State University

Assessment of End-organ Perfusion with ICG Angiography after Endovascular Interventions

in CLI

Disclosure

Larry J. Diaz, Sandoval, MD, FACC, FSCAI, FAHA, FSVM

.................................................................................

I have the following potential conflicts of interest to report:

Consulting: CSI, Cordis, Terumo.

These are not relevant to this presentation.

THANKS:

THANKS:

“There is nothing permanent…

except change”

Heraclitus (4th BC)

Indocyanin Green Angiography

! Medial calcinosis, scars, wounds, amputations, infection & edema limit evaluation of tissue perfusion with currently available tools.

! ICG absorbs and reflects light which is

captured by the imaging head

Perry D, et al. J Diabetes Sci Technol 2012;6(1):204-208

ICG ANGIOGRAPHY

! Parameters assessed ! Ingress (Pixel Strength). ! Ingress Rate (Pixels / second).

! Ingress of 27.3 Px and Ingress rate of 1.1 Px/Sec correlated with ABI >0.4

! ICG angiography provides quantitative assessment of perfusion after revascularization of diabetic patients with foot wounds.

! No baseline for comparison

1.  Braun JD, Rajguru P, Armstrong DG, Mills JL. J Vasc Surg 2014. 60(2):538

ICG ANGIOGRAPHY

! 24 patients, 31 procedures.

! Only 13 matched pre-post images. ! Parameters assessed

! Ingress / Ingress Rate.

! Egress / Egress rates. ! ABI showed “significant correlation” with TP,

Ingress & Egress rates

! 50% had “non-interpretable ABIs”

1.  Braun JD, Trinidad-Hernandez M, Perry D, Armstrong DG, Mills JL. J Vasc Surg 2013. 57:1213-8

DEMOGRAPHICS

RESULTS

REPRESENTATIVE CASE: 67 yo F

REPRESENTATIVE CASE: 67 yo F

REPRESENTATIVE CASE: 67 yo F

REPRESENTATIVE CASE: 67 yo F

REPRESENTATIVE CASE: 67 yo F

CONCLUSIONS ! Largest study to analyze matched pairs of

imaging sequences in CLI patients before & after PVI.

! Patterns of Ingress, Ingress Rates, TPF need to

be followed to determine correlation with clinical outcomes (wound healing), and determine use of the technology to predict “on table” performance.

LIMITATIONS

! Challenging to consistently obtain adequate images.

! Validation of a baseline standardized protocol

of image acquisition & interpretation is necessary.

! Correlations of metrics with NI perfusion

studies are flawed by the intrinsic flaws of NI studies in CLI.

LIMITATIONS

! Depth of penetration is limited to 5 mm. ! Cost of the system may prove prohibitive for

disseminated use.

“On Table” Perfusion

Perfusion Imaging

“The best way to predict the future, is to create it”

PETER DRUCKER

Skin Perfusion Pressure

! Assessment of microcirculation (capillary flow) with laser Doppler.

! SPP < 20 mmHg indicates poor healing

potential.

! SPP > 30 mmHg predicts good chance of healing.

Castronuovo J, et al. J Vasc Surg 1997;26:629-37. Utsunomiya M, et al. JACC 2013;61(10): E1805

Skin Perfusion Pressure

ICG ANGIOGRAPHY

1.  Braun JD, Trinidad-Hernandez M, Perry D, Armstrong DG, Mills JL. J Vasc Surg 2013. 57:1213-8

ICG ANGIOGRAPHY

1.  Braun JD, Trinidad-Hernandez M, Perry D, Armstrong DG, Mills JL. J Vasc Surg 2013. 57:1213-8

ICG ANGIOGRAPHY

1.  Braun JD, Trinidad-Hernandez M, Perry D, Armstrong DG, Mills JL. J Vasc Surg 2013. 57:1213-8

!  ICG binds to plasma albumin upon IV injection. !  Excrets through the biliary system, unconjugated !  Half-life: 2.5 to 3 minutes. !  Can be safely administered multiple times !  Low incidence of adverse reactions (1/60,000

doses) !  The 40 mW/cm laser at 806 nm excites the

molecule which fluoresces at 830 nm. !  Fluorescence is detected by the camera showing

greater intensity at areas of increased perfusion.

TIME TO PEAK FLUORESCENCE

Pre-PVI TPF

Post-PVI TPF

Ingress Rate

Pre-PVI TPF

Post-PVI TPF