Transmetatarsal Amputation: What is the Optimal Revascularization - PDF document

Transmetatarsal Amputation: What is the Optimal Revascularization Strategy? Warren Gasper MD Assistant Professor of Surgery UCSF Vascular Surgery Chief, Vascular Surgery Section San Francisco VA Health Care System UCSF Vascular Surgery Symposium 2019 4/5/2019 Disclosures: None 2 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 1 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

Transmetatarsal Amputation (TMA) § First described by Bernard and Huete in 1855 for trench foot then refined by McKittrick in 1949 for the management of gangrene and diabetic foot infections, transmetatarsal amputation (TMA) provides the opportunity for limb salvage in the face of extensive digit and forefoot wounds § Opportunity to maintain ambulatory status in patients with severe limb threat due to infection, ischemia or both • Excluding cases for trauma, series report 60-80% of patients with healed TMAs are ambulatory Wallace, Clin Podiatr Med Surg 2005 | Landry, Arch Surg 2011. 3 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 4 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 2 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

Provider and patient commitment to frequent follow-up Patient compliance TMA length Soft tissue coverage Foot stability/ROM Ambulatory Status Co-morbidities Extent of tissue loss Ischemia Infection 5 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 20 years of TMA results: 1 year limb salvage rates 50-70% 1 year major amputation rates 30-40% 3-year survival rates of 35-65% 1-year reintervention/wound rate 30-40% 6 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 3 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

Rising to the challenge of the TMA § Many series are from vascular centers and are biased to PAD § Peripheral artery disease is associated with a 2-3 times increase in risk of major amputation and death § End stage renal disease is also a strong risk factor for major amputation and death Months Roukis, Foot Ankl Spec 2010 7 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 Total PAD No PAD p UCSF TMA Experience (n=135) (n=88) (n=47) Age, y 61.5 ± 11.5 64.4 ± 11.3 55.9 ± 9.9 <.001 Male gender 109 (81%) 67 (76%) 42 (89%) .06 BMI 28.7 ± 6.5 28.1 ± 6.4 29.6 ± 6.7 .3 HTN 110 (81%) 74 (84%) 36 (77%) .3 DM 118 (87%) 76 (86%) 42 (89%) .5 CAD 44 (33%) 43 (49%) 1 (2%) <.001 § 147 consecutive TMAs in 135 PAD 88 (65%) 88 (100%) 0 (0%) <.001 patients from 2008 to 2016 at COPD 10 (7%) 9 (10%) 1 (2%) .09 UCSF, SFGH and SFVA CKD 39 (29%) 29 (33%) 10 (21%) .2 ESRD 23 (17%) 19 (22%) 4 (9%) .05 Prior CVA 14 (10%) 13 (15%) 1 (2%) .02 HIV 3 (2%) 1 (1%) 2 (4%) .2 Organ transplant 8 (6%) 7 (8%) 1 (2%) .2 Wound grade Wifi 1/2 20 (15%) 8 (9%) 12 (26%) .01 Wifi 3 57 (42%) 34 (39%) 23 (49%) .2 8 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 Wifi 4 58 (43%) 46 (52%) 12 (25%) .003 4 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

Total PAD No PAD p Who does not have PAD? (n=135) (n=88) (n=47) Age, y 61.5 ± 11.5 64.4 ± 11.3 55.9 ± 9.9 <.001 Male gender 109 (81%) 67 (76%) 42 (89%) .06 BMI 28.7 ± 6.5 28.1 ± 6.4 29.6 ± 6.7 .3 § Only 45% of limbs had an ABI, 1/3 HTN 110 (81%) 74 (84%) 36 (77%) .3 of the values were >1.3 DM 118 (87%) 76 (86%) 42 (89%) .5 § Only 24% of limbs had a toe CAD 44 (33%) 43 (49%) 1 (2%) <.001 pressure PAD 88 (65%) 88 (100%) 0 (0%) <.001 COPD 10 (7%) 9 (10%) 1 (2%) .09 Ø Clearly PAD is under diagnosed CKD 39 (29%) 29 (33%) 10 (21%) .2 Ø An accurate quantitative measure ESRD 23 (17%) 19 (22%) 4 (9%) .05 of ischemia is difficult Prior CVA 14 (10%) 13 (15%) 1 (2%) .02 HIV 3 (2%) 1 (1%) 2 (4%) .2 Organ transplant 8 (6%) 7 (8%) 1 (2%) .2 Wound grade Wifi 1/2 20 (15%) 8 (9%) 12 (26%) .01 Wifi 3 57 (42%) 34 (39%) 23 (49%) .2 9 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 Wifi 4 58 (43%) 46 (52%) 12 (25%) .003 Total PAD No PAD p UCSF TMA Experience (n=135) (n=88) (n=47) Age, y 61.5 ± 11.5 64.4 ± 11.3 55.9 ± 9.9 <.001 Male gender 109 (81%) 67 (76%) 42 (89%) .06 BMI 28.7 ± 6.5 28.1 ± 6.4 29.6 ± 6.7 .3 § 147 consecutive TMAs in 135 HTN 110 (81%) 74 (84%) 36 (77%) .3 patients from 2008 to 2016 at DM 118 (87%) 76 (86%) 42 (89%) .5 UCSF, SFGH and SFVA CAD 44 (33%) 43 (49%) 1 (2%) <.001 § Median follow-up was 3.3 years PAD 88 (65%) 88 (100%) 0 (0%) <.001 COPD 10 (7%) 9 (10%) 1 (2%) .09 § Overall TMA healing rate 60% CKD 39 (29%) 29 (33%) 10 (21%) .2 • 75% non-PAD vs 52% PAD ESRD 23 (17%) 19 (22%) 4 (9%) .05 Prior CVA 14 (10%) 13 (15%) 1 (2%) .02 § Major Amputation rate 22% HIV 3 (2%) 1 (1%) 2 (4%) .2 • 10% non-PAD vs 28% PAD Organ transplant 8 (6%) 7 (8%) 1 (2%) .2 § 3-year survival 75% by KM Wound grade Wifi 1/2 20 (15%) 8 (9%) 12 (26%) .01 Wifi 3 57 (42%) 34 (39%) 23 (49%) .2 10 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 Wifi 4 58 (43%) 46 (52%) 12 (25%) .003 5 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

UCSF TMA Experience Overall Survival 1.00 Rates of TMA Healing 0.75 1.00 0.50 0.75 0.25 p = 0.02 (Log-rank) 0.50 0.00 0.25 p = 0.003 (Log-rank) 1 2 3 4 5 analysis time (y) Number at risk 0.00 No PAD 47 46 40 30 16 11 1 2 3 4 5 PAD 88 76 54 40 22 16 analysis time (y) No PAD PAD Number at risk No PAD 51 17 8 6 3 2 PAD 94 42 26 18 5 5 No PAD PAD 11 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 UCSF TMA Experience § 61 limbs had a revascularization procedure during the index TMA Open hospitalization • Timing: revasc + TMA occurred within 4d (median, IQR 2-7d) Endo • 87% of revascularizations occurred before TMA § Improvement in TMA healing rate for PAD pts (71% vs 57%) § Late revascularization did not help § Graft/vessel patency was associated with healing and limb loss 12 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 6 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

Timing of Revascularization and TMA § Sheahan et al (2005) found that a revascularization after toe amputation was associated with an increased risk of major limb loss (OR 2.11 95%CI 1.39-4.21) compared to bypass before amputation § Shi et al (2018) found no difference in the timing of revascularization (*all bypass procedures were pre-TMA). However TMA healing with endovascular procedures was similar to no treatment • Endovascular 50.6% vs Bypass 87% • No treatment 51% Sheahan, JVS 2005 | Shi J Foot Ankl Surg 2018 13 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 Adequate Perfusion after TMA: do you have it? § The plantar flap is fed by the posterior tibial artery § Angiographic characteristics of the foot were also investigated in a subset of the UCSF cohort using the GLASS and Kawarada scoring systems • Intact pedal arch and 2 pedal arteries on the foot were associated with healing (p=.07) 14 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 Fig. 4. Anterior tibial artery insufficiency. In the situation of anterior tibial artery insuf- ficiency, flow through the posterior tibial artery to the plantar flap is antegrade, while flow through the dorsalis pedis artery to the dorsal flap is retrograde. If the anastomosis is 7 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]

Conclusions § Transmetatarsal amputations are a valuable but demanding procedure for limb salvage, even in patients with PAD § Revascularization prior to TMA appears to perform significantly better § Open surgery (bypass) has significantly better outcomes than endovascular § Peripheral artery disease is under diagnosed in patients with advanced limb threat (calcified toes, lack of accurate toe measurements, urgent surgery for infection) • Palpable pulses are not sufficient to assess for adequate perfusion before TMA § Angiosome and pedal arch anatomy have real clinical correlations but the value of targeted revascularization is unclear 15 Optimal revascularization strategy for TMA | UCSF Vascular Symposium 2019 4/5/2019 8 4/8/19 [ADD PRESENTATION TITLE: INSERT TAB > HEADER & FOOTER > NOTES AND HANDOUTS]