Vascular Graft Surveillance. Joel Baumgartner May 8, 2006

Transcription

1 Vascular Graft Surveillance Joel Baumgartner May 8, 2006

2 History General indications for lower extremity vascular bypass

3 History General indications for lower extremity vascular bypass Rest pain

4 History General indications for lower extremity vascular bypass Rest pain Nonhealing ischemic ulcer

5 History Saphenous vein as conduit for femoropopliteal bypass first described by Kunlin in 1948 Strandness DE, et al. Circ. 2000;40-46.

6 History Saphenous vein as conduit for femoropopliteal bypass first described by Kunlin in 1948 Originally described as a reversed saphenous graft, but now in situ grafts with lysis of valves also used Strandness DE, et al. Circ. 2000;40-46.

7 History Saphenous vein as conduit for femoropopliteal bypass first described by Kunlin in 1948 Originally described as a reversed saphenous graft, but now in situ grafts with lysis of valves also used Saphenous vein first consistently used as a vascular graft below the inguinal ligament in the Korean conflict for lower extremity arterial trauma Strandness DE, et al. Circ. 2000;40-46.

8 Khatri: Op Surg Man. 2003:261.

9 Townsend: Sabiston Text Surg. 2004:2015.

10 Terminology Graft failure v. graft stenosis v. graft patency

11 Graft Failure Defined as a graft with no patency, is thrombosed

12 Graft Failure Incidence As high as 15-24% by 21 months postoperatively Smeets L, et al. Eur J Vasc Endovasc Surg. 2005

13 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error

14 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error 3-5% incidence with vein grafts Mills JL. Sem Vasc Surg Jun;6(2):78-91.

15 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error 3-5% incidence with vein grafts Kinked or twisted graft

16 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error 3-5% incidence with vein grafts Kinked or twisted graft Failure to lyse valves

17 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error 3-5% incidence with vein grafts Kinked or twisted graft Failure to lyse valves Anastomotic error

18 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error 3-5% incidence with vein grafts Kinked or twisted graft Failure to lyse valves Anastomotic error Small or poor quality vein

19 Graft Failure Incidence As high as 15-24% by 21 months postoperatively First 30 days after bypass from technical error 3-5% incidence with vein grafts Kinked or twisted graft Failure to lyse valves Anastomotic error Small or poor quality vein Poor outflow artery

20 Graft Failure Incidence Intermediate failure (30 days 2 yrs) from graft stenosis from intimal hyperplasia

21 Graft Failure Incidence Intermediate failure (30 days 2 yrs) from graft stenosis from intimal hyperplasia Stenosis can be altered with interventions

22 Graft Failure Incidence Intermediate failure (30 days 2 yrs) from graft stenosis from intimal hyperplasia Stenosis can be altered with interventions Reason for graft surveillance during this time period

23 Graft Failure Incidence Late failure (after 2 years) primarily from progression of atherosclerosis in inflow and outflow arteries, less often in vein graft itself

24 Graft Stenosis Incidence of stenosis 25-30% in first year after vein bypass Mills JL. Semin Vasc Surg Jun;6(2):78-91.

25 Graft Stenosis Incidence of stenosis 25-30% in first year after vein bypass Standard definition of stenosis: classically based on angiogram with 50% stenosis hemodynamically significant Mills JL. Semin Vasc Surg Jun;6(2):78-91.

26 Graft Stenosis Incidence of stenosis 25-30% in first year after vein bypass Standard definition of stenosis: classically based on angiogram with 50% stenosis hemodynamically significant Newer definition based on Ultrasound Mills JL. Semin Vasc Surg Jun;6(2):78-91.

27 Graft Stenosis Incidence of stenosis 25-30% in first year after vein bypass Standard definition of stenosis: classically based on angiogram with 50% stenosis hemodynamically significant Newer definition based on Ultrasound Typically occur at anastomoses or valves Mills JL. Semin Vasc Surg Jun;6(2):78-91.

28 Graft Patency Standardized definitions

29 Graft Patency Standardized definitions Primary: patency with no intervention Rutherford RB, et al. J Vasc Surg Sep;26(3):

30 Graft Patency Standardized definitions Primary: patency with no intervention Assisted primary: patency after intervention only for stenosis Rutherford RB, et al. J Vasc Surg Sep;26(3):

31 Graft Patency Standardized definitions Primary: patency with no intervention Assisted primary: patency after intervention only for stenosis Secondary: patency after intervention for occlusion Rutherford RB, et al. J Vasc Surg Sep;26(3):

32 History of Ultrasound Piezoelectric effect first described by Pierre and Jacques Curie

33 History of Ultrasound Piezoelectric effect first described by Pierre and Jacques Curie However Uncompaghre Ute Indians of central Colorado used piezoelectricity in rattles of quartz for religious ceremonies

34 History of Ultrasound

35 History of Ultrasound Sound Navigation and Ranging (SONAR) in WWII

36 History of Ultrasound Sound Navigation and Ranging (SONAR) in WWII Doppler effect first described by Johann Doppler

37 History of Ultrasound Sound Navigation and Ranging (SONAR) in WWII Doppler effect first described by Johann Doppler Change in frequency of reflected sound waves from moving source

38 History of Ultrasound

39 History of Ultrasound Use developed in vascular imaging as noninvasive alternative to angiogram

40 History of Ultrasound Use developed in vascular imaging as noninvasive alternative to angiogram Accurate: estimated 96.9% sensitivity, 96.2% specificity, 94.6% PPV, 97.8% NPV for lower extremity vascular occlusive disease Alexander JQ, et al. Am Surg Dec;68(12):

41 History of Ultrasound Use developed in vascular imaging as noninvasive alternative to angiogram Accurate: estimated 96.9% sensitivity, 96.2% specificity, 94.6% PPV, 97.8% NPV for lower extremity vascular occlusive disease Extended to postoperative evaluation of vascular grafts

42 Duplex Ultrasound Wetzner SM, et al. Radiology. 1984;150:

43 Duplex Ultrasound Wetzner SM, et al. Radiology. 1984;150:

44 Duplex Ultrasound Wetzner SM, et al. Radiology. 1984;150:

45 Duplex Ultrasound Wetzner SM, et al. Radiology. 1984;150:

46 Duplex Ultrasound Grainger & Allison's Diag Rad. 2001:69.

47 Duplex Ultrasound TABLE 3B-4 -- Diagnostic criteria for abnormal flow in the arteries of the leg Diameter reduction (%) Velocity changes at lesion Systolic velocity increase of % compared with normal segment proximal to stenosis Systolic velocity increase of 100% or more Spectral changes beyond lesion Spectral broadening apparent No normal flow reversal present 100 Velocity measurements proximal to occlusion decreased (increased resistance) No detectable flow Grainger & Allison's Diag Rad. 2001:69.

48 Duplex Ultrasound

49 First Prospective Randomized Trial 156 patients randomized to clinical surveillance or Duplex surveillance after femoropopliteal or femorodistal bypass Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

50 First Prospective Randomized Trial 156 patients randomized to clinical surveillance or Duplex surveillance after femoropopliteal or femorodistal bypass Surveillance carried out to 36 months Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

51 First Prospective Randomized Trial Standardized management Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

52 First Prospective Randomized Trial Standardized management clinical signs of failing graft (disabling claudication, ischemic ulcers, etc.), decrease in ABI by 0.15, or Duplex with stenosis of >50% went to angiogram Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

53 First Prospective Randomized Trial Standardized management clinical signs of failing graft (disabling claudication, ischemic ulcers, etc.), decrease in ABI by 0.15, or Duplex with stenosis of >50% went to angiogram Angio with >50% stenosis went to revision Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

54 First Prospective Randomized Results Trial Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

55 First Prospective Randomized Results Trial Significantly improved assisted primary patency in Duplex group compared to clinical group after 3 years (78% v. 53%, p < 0.05) Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

56 First Prospective Randomized Results Trial Significantly improved assisted primary patency in Duplex group compared to clinical group after 3 years (78% v. 53%, p < 0.05) Also significantly improved secondary patency in Duplex group (82% v. 56%, p < 0.05) Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

57 First Prospective Randomized Results Trial Significantly improved assisted primary patency in Duplex group compared to clinical group after 3 years (78% v. 53%, p < 0.05) Also significantly improved secondary patency in Duplex group (82% v. 56%, p < 0.05) No demonstration of decreased amputation rates Lundell, A, et al. J Vasc Surg Jan;21(1);26-33.

58 Second RCT 179 patients 30 days after infrainguinal bypass randomized to Duplex or clinical surveillance for 12 months Ihlberg L, et al. Eur J Vasc Endovasc Surg. 1998

59 Second RCT 179 patients 30 days after infrainguinal bypass randomized to Duplex or clinical surveillance for 12 months No significant difference in assisted primary patency, secondary patency, or limb salvage rates between the two groups Ihlberg L, et al. Eur J Vasc Endovasc Surg. 1998

60 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Davies AH, et al. Circulation Sep 27;112(13):

61 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Patients selected 30 days after infrainguinal vein bypass Davies AH, et al. Circulation Sep 27;112(13):

62 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Patients selected 30 days after infrainguinal vein bypass Patients selected from 29 centers in the UK and Europe from April 1998 to December 2001 Davies AH, et al. Circulation Sep 27;112(13):

63 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Randomized to clinical follow up or Duplex surveillance Davies AH, et al. Circulation Sep 27;112(13):

64 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Randomized to clinical follow up or Duplex surveillance Appointments at 6 weeks (time of average recruitment), then at 3, 6, 9, 12 and 18 months Davies AH, et al. Circulation Sep 27;112(13):

65 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Randomized to clinical follow up or Duplex surveillance Appointments at 6 weeks (time of average recruitment), then at 3, 6, 9, 12 and 18 months Clinical follow-up arm with ABI measurements and Duplex at 18 months (solely to identify the incidence of stenosis) Davies AH, et al. Circulation Sep 27;112(13):

66 Vein Graft Surveillance Randomised Trial (VGST) Randomized controlled trial of 594 patients Randomized to clinical follow up or Duplex surveillance Appointments at 6 weeks (time of average recruitment), then at 3, 6, 9, 12 and 18 months Clinical follow-up arm with ABI measurements and Duplex at 18 months (solely to identify the incidence of stenosis) Duplex Surveillance arm with Duplex US at each appointment Davies AH, et al. Circulation Sep 27;112(13):

67 VGST Patients managed according to findings in each arm Davies AH, et al. Circulation Sep 27;112(13):

68 VGST Patients managed according to findings in each arm Need for and type of intervention not standardized, left up to discretion of each center Davies AH, et al. Circulation Sep 27;112(13):

69 VGST Patients managed according to findings in each arm Grafts at risk of failure with various criteria Davies AH, et al. Circulation Sep 27;112(13):

70 VGST Patients managed according to findings in each arm Grafts at risk of failure with various criteria Clinical signs: disabling claudication, ischemic pain or ulcers Davies AH, et al. Circulation Sep 27;112(13):

71 VGST Patients managed according to findings in each arm Grafts at risk of failure with various criteria Clinical signs: disabling claudication, ischemic pain or ulcers ABI: decrease of 0.1 or greater Davies AH, et al. Circulation Sep 27;112(13):

72 VGST Patients managed according to findings in each arm Grafts at risk of failure with various criteria Clinical signs: disabling claudication, ischemic pain or ulcers ABI: decrease of 0.1 or greater Duplex: peak systolic flow less than 45 cm/s, peak systolic velocity ratio greater than 2 (peak systolic velocity at site of stenosis/peak systolic velocity at any point within 2 cm of normal adjacent graft) Davies AH, et al. Circulation Sep 27;112(13):

73 VGST Outcomes Davies AH, et al. Circulation Sep 27;112(13):

74 VGST Outcomes Primary Davies AH, et al. Circulation Sep 27;112(13):

75 VGST Outcomes Primary Time to amputation Davies AH, et al. Circulation Sep 27;112(13):

76 VGST Outcomes Primary Time to amputation Time to vascular mortality: death from MI, CHF, arrythmia or stroke Davies AH, et al. Circulation Sep 27;112(13):

77 VGST Outcomes Primary Time to amputation Time to vascular mortality: death from MI, CHF, arrythmia or stroke Secondary Davies AH, et al. Circulation Sep 27;112(13):

78 VGST Outcomes Primary Time to amputation Time to vascular mortality: death from MI, CHF, arrythmia or stroke Secondary Patency: as defined by Rutherford et al Davies AH, et al. Circulation Sep 27;112(13):

79 VGST Outcomes Primary Time to amputation Time to vascular mortality: death from MI, CHF, arrythmia or stroke Secondary Patency: as defined by Rutherford et al Cost: obtained for each patient by adding costs of Duplex scans, angiograms and interventions Davies AH, et al. Circulation Sep 27;112(13):

80 VGST Outcomes Primary Time to amputation Time to vascular mortality: death from MI, CHF, arrythmia or stroke Secondary Patency: as defined by Rutherford et al Cost: obtained for each patient by adding costs of Duplex scans, angiograms and interventions Qaulity-of-life: at 6 and 18 months by SF-36 and EuroQol questionnaires Davies AH, et al. Circulation Sep 27;112(13):

81 VGST Results Davies AH, et al. Circulation Sep 27;112(13):

82 VGST Davies AH, et al. Circulation Sep 27;112(13):

83 VGST Results Amputations and vascular mortality not significantly different between the two groups (7% v. 7% & 10% v. 12% respectively) Davies AH, et al. Circulation Sep 27;112(13):

84 VGST Results Amputations and vascular mortality not significantly different between the two groups (7% v. 7% & 10% v. 12% respectively) Graft stenosis significantly greater in the clinical group than the Duplex group (19% v. 12%, p = 0.04) Davies AH, et al. Circulation Sep 27;112(13):

85 VGST Davies AH, et al. Circulation Sep 27;112(13):

86 VGST Davies AH, et al. Circulation Sep 27;112(13):

87 VGST Davies AH, et al. Circulation Sep 27;112(13):

88 VGST Results No significant difference between quality-oflife assessments between the two groups Davies AH, et al. Circulation Sep 27;112(13):

89 VGST Results No significant difference between quality-oflife assessments between the two groups Average cost per patient significantly higher in the Duplex group than the clinical group ( 1371 v. 876, p = 0.002) Davies AH, et al. Circulation Sep 27;112(13):

90 VGST Davies AH, et al. Circulation Sep 27;112(13):

91 VGST Additional Results Diagnostic interventions greater in clinical group (31% v. 22%, p = 0.01) Davies AH, et al. Circulation 2005 Sep 27;112(13):

92 VGST Additional Results Diagnostic interventions greater in clinical group (31% v. 22%, p = 0.01) Therapeutic interventions greater in Duplex group but not significantly different (16% v. 22%, p = 0.07) Davies AH, et al. Circulation 2005 Sep 27;112(13):

93 VGST Conclusions No difference in limb salvage

94 VGST Conclusions No difference in limb salvage Increased cost for ultrasound surveillance

95 VGST Problems with trial No standard treatment for stenosis (lack of benefit in Duplex group may be secondary to suboptimal treatment)

96 VGST Problems with trial No standard treatment for stenosis (lack of benefit in Duplex group may be secondary to suboptimal treatment) Less stenosis than previously published

97 VGST Problems with trial No standard treatment for stenosis (lack of benefit in Duplex group may be secondary to suboptimal treatment) Less stenosis than previously published Synthetic grafts not evaluated

98 Conclusion Stenosis is common, but treatable

99 Conclusion Stenosis is common, but treatable Largest RCT without benefit in limb loss, patency, QOL or cost

100 Conclusion Stenosis is common, but treatable Largest RCT without benefit in limb loss, patency, QOL or cost Increased interventions in US surveillance programs do not yield improved patency or limb salvage and are costly