QUANTIFYING ANGIOPLASTY RESULTSBEYOND ANGIOGRAPHY

Stavros Spiliopoulos

Asst. Professor in Interventional Radiology

University of Athens

2nd Radiology Department, Interventional Radiology Unit

“ΑΤΤΙΚΟΝ” University General HospitalUnit Director: Prof Elias Brountzos

Director: Prof Nikolaos Kelekis

Disclosures

❑I do not have any potential conflict of interest

EVALUATION OF PERIPHERAL ENDOVASCULAR TREATMENT OUTCOMES

Outcome evaluation

• Final result: DSA

• Physical exam

• ABI/TBI

• Imaging: DUS, MRA, CTA

EVALUATION OF ENDOVASCULAR TREATMENT OUTCOMES

• Primary goal of revascularization Tissue perfusion

• Using ABI/TBI and standard MRI, CTA, DUS we cannot

obtain measurements of foot tissue perfusion

NON INVASIVE TISSUE PERFUSION METHODS TOQUANTIFY MICROVASCULAR PERFUSION

• Transcutaneous partial oxygen pressure

(TCPO2): transcutaneous oximetry 1-2 mm

below skin surface. Measures the local O2

released from the skin through the capillaries.

• Skin perfusion pressure (SSP) reflects the local

pressure in the microcirculation

• SPP >40mmHg and TCPO2 >30mmHg have been

correlated with improved wound healing.

QUANTIFICATION OF TISSUE PERFUSIONIS IT NECESSARY?

• Objective measurement of endovascular treatment outcome

• Final angiogram: “looks good”, “I don’t like it” “I think…”

Quantification of outcomes

• During the procedure:

✓More vessels?

✓More luminal gain?

• Follow up:

✓Prognosis of limb salvage/wound healing

✓Decision to proceed to reintervention

Limb perfusion quantification and monitoring modalities

PET

MRI

CTA

Indocyanine green fluorescence angiography

Laser Doppler flowmetry/imaging

Transcutaneous partial oxygen pressure (TCPO2)

Skin perfusion pressure (SSP)

Implantable micro-O2 sensors (MOXYs)

Microwave Radiometry

2D perfusion DSA

Laser Doppler oximetry of venous reserve (INVOS)

INTRA-PROCEDURAL TISSUE PERFUSION QUANTIFICATION

2D Perfusion DSABefore

(Io)

After (I) % Rise 100*(I-Io)/Io

Mean Transit

Time (MTT)1) 17,2526 5,7686

-66,5639

2) 15,7569 7,2700-53,8615

3) 16,0059 10,8468-32,2325

4) 19,0000 11,7872-38

rPBF1) 0,0153 0,0772

404,5752

2) 0,0129 0,0414220,9302

3) 0,0241 0,0804233.61

4) 0,0039 0,06061453,8462

PBV1) 0,2218 0,3893

75,5185

2) 0,1696 0,237139,7995

3) 0,3588 0,409314,0747

4) 0,0747 0,4702529,4511

1

23 4

2D Perfusion DSAReal-time quantification of revascularization

INTRA-PROCEDURAL TISSUE PERFUSION EVALUATION

BASELINE + PERONEAL + PERONEAL + PTA

BASELINE Blood flow: +63% Blood flow: +81%

Mean transit time (slope)

Color-coded perfusion maps

Quantification of tissue perfusion

• Papaverin-induced peripheral-virtual FFR values

• Post-processing of the contrast curves of 2D Perfusion DSA

REAL-TIME QUANTIFICATION OF REVASCULARIZATION

Work in progress

MODALITIES FOR THE QUANTIFICATION OF TISSUE METABOLIC ACTIVITY

INVOS SYSTEM REAL-TIME TISSUE PERFUSION MONITORING

• INVOS (Medtronic) non invasive real time local

assessment of the % of tissue oxyhemoglobin

(depth:1-3 cm)

• Transcutaneous laser micro-sensors (near-infrared

light at 730 and 810 nm wavelengths that are

absorbed by hemoglobin).

• Real-time tissue perfusion monitoring

INVOS SYSTEM TISSUE PERFUSION MONITORING

• Normal values: 40-50%

• Acute ischemia: <20%

CLI CASE

CLI 1

0

10

20

30

40

50

60

70

80

90

1

39

77

11

5

15

3

19

1

22

9

26

7

30

5

34

3

38

1

41

9

45

7

49

5

53

3

57

1

60

9

64

7

68

5

72

3

76

1

79

9

83

7

87

5

91

3

95

1

98

9

10

27

10

65

11

03

11

41

11

79

12

17

12

55

12

93

13

31

13

69

14

07

14

45

14

83

15

21

15

59

15

97

16

35

16

73

17

11

17

49

17

87

18

25

18

63

19

01

19

39

19

77

20

15

20

53

20

91

21

29

21

67

22

05

22

43

22

81

23

19

23

57

23

95

24

33

24

71

25

09

25

47

25

85

26

23

26

61

26

99

27

37

27

75

28

13

28

51

28

89

29

27

29

65

30

03

30

41

30

79

31

17

31

55

Arm

Target limb

3 h

Revascularization

•Fem-fem bypass 7 days ago

•DUS low flow

•No clinical improvement

2.5mm

3 mm

Near infrared spectrometry (NIRS)

Continuous, non-invasive monitoring of tissue oxygen balance

COMMERCIALLY AVAILABLE TISSUE PERFUSION MONITORING SYSTEMS

•HyperView (HyperMed Imaging; Memphis, USA)•Hyperspectral imaging for superficial tissue oximetry• Measurement of oxyhemoglobin, deoxyhemoglobin and oxyhemoglobin saturation in superficial limb tissue•CE-Mark

CONCLUSIONS

of tissue perfusion and metabolic

activity during and following endovascular procedures is feasible

• HOT TOPIC currently under investigation

• Initial results are encouraging

• Quantification of outcomes and improvement of surveillance is

essential for the optimization of endovascular treatment

THANK YOU FOR YOUR ATTENTION