Influence of a Novel Morphology-Driven Classification on Limb Salvage after Isolated Tibial Intervention for Chronic Limb Threatening Ischemia.

BACKGROUND: Infra-popliteal interventions for chronic limb-threatening ischemia (CLTI) can be impacted by the morphology of the tibial vessels. The aim of this study was to examine the impact of a novel morphology-driven classification on the outcomes of isolated tibial intervention for CLTI. METHODS: A database of patients undergoing isolated tibial interventions for CLTI at a single center between 2010 and 2020 was retrospectively queried. Patients with isolated infra-popliteal disease were identified, and their anatomy was scored as present or absent for lesion calcification (1 point), target vessel diameter<3.0 mm (1 point), lesion length>300 mm (1 point), and poor pedal runoff score (1 point). Patients were then divided into 3 groups: low risk (0 or 1 points), moderate risk (2 points), and high risk (3 or 4 points). Intention to treat analysis by the patient was performed. Limb-based patency (the absence of reintervention, occlusion, critical stenosis [>70%], or hemodynamic compromise with ongoing symptoms of CLTI as it related to the patency of the preoperatively determined target artery pathway) was assessed. Patient-oriented outcomes of amputation-free survival (AFS; survival without major amputation) and freedom from major adverse limb events (MALE; above ankle amputation of the index limb or major reintervention: new bypass graft, jump/interposition graft revision) were evaluated. RESULTS: 1,607 patients (55% male, average age 60 years, 3,846 vessels) underwent tibial intervention for CLTI. The majority of the patients were diabetic and of Hispanic origin. Morphologically, 27%, 31%, and 42% of the vessels were categorized as low risk, moderate risk, and high risk, respectively. There was a significant worsening of the infra-popliteal Global Limb Anatomic Staging System (GLASS) grading as the morphological risk increased. The 30-day major adverse cardiac events (MACE) were equivalent across the groups and were under the stated objective performance goal (OPG) of ≤10%. In contrast, both the 30-day MALE and the 30-day major amputations were significantly different across the groups, with the low-risk group remaining under the OPG of ≤9% and ≤4%, respectively, while the moderate risk and high risk exceeded the goal threshold. For the OPG, freedom from MALE was 60 ± 5%, 46 ± 5%, and 22 ± 9% at 5 years for low-, moderate-, and high-risk groups, respectively (mean ± standard error of the mean; P = 0.008). Overall AFS was 55 ± 5%, 37 ± 6%, and 18 ± 7% at 5 years for low-, moderate-, and high-risk groups, respectively (mean ± standard error of the mean; P = 0.003). CONCLUSIONS: Tibial anatomic morphology impacts isolated tibial endovascular intervention with adverse morphology associated with poorer short- and long-term outcomes. Risk stratification based on anatomic predictors should be an additional consideration as one intervenes on infra-popliteal vessels for CLTI.

Artificial intelligence of arterial Doppler waveforms to predict major adverse outcomes among patients with diabetes mellitus.

OBJECTIVE: Patients with diabetes mellitus (DM) are at increased risk for peripheral artery disease (PAD) and its complications. Arterial calcification and non-compressibility may limit test interpretation in this population. Developing tools capable of identifying PAD and predicting major adverse cardiac event (MACE) and limb event (MALE) outcomes among patients with DM would be clinically useful. Deep neural network analysis of resting Doppler arterial waveforms was used to detect PAD among patients with DM and to identify those at greatest risk for major adverse outcome events. METHODS: Consecutive patients with DM undergoing lower limb arterial testing (April 1, 2015-December 30, 2020) were randomly allocated to training, validation, and testing subsets (60%, 20%, and 20%). Deep neural networks were trained on resting posterior tibial arterial Doppler waveforms to predict all-cause mortality, MACE, and MALE at 5 years using quartiles based on the distribution of the prediction score. RESULTS: Among 11,384 total patients, 4211 patients with DM met study criteria (mean age, 68.6 ± 11.9 years; 32.0% female). After allocating the training and validation subsets, the final test subset included 856 patients. During follow-up, there were 262 deaths, 319 MACE, and 99 MALE. Patients in the upper quartile of prediction based on deep neural network analysis of the posterior tibial artery waveform provided independent prediction of death (hazard ratio [HR], 3.58; 95% confidence interval [CI], 2.31-5.56), MACE (HR, 2.06; 95% CI, 1.49-2.91), and MALE (HR, 13.50; 95% CI, 5.83-31.27). CONCLUSIONS: An artificial intelligence enabled analysis of a resting Doppler arterial waveform permits identification of major adverse outcomes including all-cause mortality, MACE, and MALE among patients with DM.

Hybrid Deep Venous ARterialisation (DVAR) for No-Option Chronic Limb Threatening Ischemia.

BACKGROUND: Hybrid Deep Venous ARterialisation (DVAR) is offered as a last-ditch attempt for limb salvage in patients with chronic limb threatening ischemia (CLTI). It provides non-selective arterialisation independent of the angiosome, which harnesses the complex venous capillary network bed developed in the leg and foot. METHODS: We present two elderly men who underwent DVAR to salvage limb with CLTI. DVAR was performed by creating an arteriovenous connection by anastomosis of the great saphenous vein (GSV) at the level of the distal popliteal and proximal tibio-peroneal trunk. Fasciotomy was performed over the length of the GSV. Subsequently, proximal in-situ catheter valvotomies of the GSV valves were undergone with the adjuvant on-table balloon maturation. The distal tarsal veins underwent balloon valvotomy under direct vision with subsequent proximal and distal tarsal veins valvuloplasties. Completion angiogram demonstrated restoration of the flow in the foot and both the patients were relieved of rest pain. CONCLUSION: We successfully performed DVAR in 2 elderly patients. Our experience shows that DVAR is a simple and safe option that is easily reproducible without the need for complex endovascular hardware, only if a suitable GSV to the foot is available with no history of deep vein thrombosis.

Balloon-Assisted Endovascular Thrombectomy for Tibial Thromboembolism.

We present a novel approach to endovascular thrombectomy using the Penumbra Indigo® Aspiration System with balloon assistance for a thromboembolic occlusion to the tibioperoneal trunk and tibial arteries causing acute limb ischemia. This technique allows for effective suction thrombectomy of distal vessels into a shorter, large-diameter aspiration catheter, thereby overcoming the limitations of the longer but smaller aspiration catheters.

The predictive value of microperfusion assessments for the follow-up of tibial bypass grafts.

OBJECTIVE: We conducted a prospective evaluation of microperfusion parameters after tibial bypass surgery was performed. Differences between grafts with occlusions during follow-up and patent grafts were analyzed in relation to the pedal arch quality. METHODS: Patients receiving tibial bypass grafts for chronic limb-threatening ischemia from 2019 to 2020 were included. Assessment of microcirculation (parameters: hemoglobin oxygen saturation [sO2] and flow) was done by laser Doppler flowmetry and white light spectrometry (oxygen-to-see), supine and in elevation, whereas the macrocirculation was evaluated by the ankle-brachial index and duplex ultrasound examination. The quality of run-off was graded for each patient. Measurements were performed preoperatively, 1 day postoperatively, and after 6 months. Patients with graft occlusions during follow-up (OCCLUDED) and patients without occlusions (OPEN) were compared. RESULTS: We included 42 patients (13 women, 29 men; mean age, 76.1 years; range, 60-89 years) were included. The patency of all grafts 1 day after the operation was confirmed by ultrasound examination. The overall analysis of the microcirculation showed significant changes in both the supine and elevated leg position between measurements taken preoperatively, 1 day after the operation, and after 6 months for the parameters sO2 and FLOW (sO2 supine, P = .001; sO2 elevated, P < .001; FLOW supine, P < .001; FLOW elevated, P < .001). The comparison of the values 1 day after the operation yielded significantly decreased microperfusion parameters (both O2 and FLOW) in the group that developed bypass occlusion in the later follow-up period (sO2 supine: OCCLUDED, 35.7% [7.3-65.0] and OPEN, 48.7% [25.0-72.3] P = .011; FLOW supine: OCCLUDED, 27.7 A.U. [12.7-52.7] and OPEN, 57.3 A.U. [16.0-106.7], P = .008). No significant differences in the severity of the arch impairment was found between the OPEN and OCCLUDED groups (P = .651). Absolute values of the parameters sO2 and flow showed no correlation with the pedal arch classification. CONCLUSIONS: Significantly poorer microperfusion was detected postoperatively in patients with later occurrence of graft occlusions despite patent grafts on the first postoperative day. Microperfusion measurements might be a possible tool for the prediction of graft failure.

United States Investigational Device Exemption study of the Revolution Peripheral Atherectomy System.

OBJECTIVE: Atherectomy has become commonplace as an adjunct to interventional treatments for peripheral arterial disease, but the procedures have been complicated by risks including distal embolization and arterial perforation. This study aimed to examine the safety and effectiveness of a novel atherectomy system to treat femoropopliteal and below-knee peripheral arterial disease. METHODS: The Revolution Peripheral Atherectomy System (Rex Medical LP, Conshohocken, Pa) was studied in 121 patients with 148 femoropopliteal and below-knee lesions, enrolled at 17 United States institutions. Technical success was defined when the post-atherectomy angiographic stenosis was ≤50%, as assessed by an independent core laboratory. Major adverse events were adjudicated by an independent Clinical Events Committee. RESULTS: Among 148 site-identified target lesions in 121 patients, 21.4% were in the superficial femoral artery, 13.7% involved the popliteal artery, and 67.9% were in tibial arteries; 3.1% involved more than one segment. Technical success was 90.2%, with stenoses decreasing from 73% ± 19% at baseline to 42% ± 14% after atherectomy. Adjunctive treatment after atherectomy included angioplasty with uncoated balloons in 91%, drug-coated balloons in 11%, bare stent deployment in 8%, and drug-eluting stent placement in 3%. Procedural success (<30% residual stenosis) was achieved in 93.7% of target lesions. Complications during the procedure included one target vessel perforation and two distal embolizations; each of which were adjudicated by the Clinical Events Committee as unrelated to the device and were not visualized angiographically by the core laboratory. Freedom from major adverse events was 97.3% through 30 days. The Kaplan-Meier estimates of primary, assisted primary, and secondary patency were 81.6%, 87.7%, and 91.6% at 6 months, respectively. CONCLUSIONS: The use of the Revolution Peripheral Atherectomy System was associated with few procedural complications and a high rate of success at the index procedure and through 6 months.

The Global Anatomic Staging System Does Not Predict Limb Based Patency of Tibial Endovascular Interventions.

OBJECTIVE: Anatomic grading systems have historically been poor predictors of patency after endovascular tibial interventions. The Global Vascular Guidelines proposed a new Global Anatomic Staging System (GLASS) to estimate one-year limb-based patency (LBP). The purpose of this study was to determine the association of GLASS with LBP following endovascular tibial interventions. METHODS: We included all patients presenting to our multidisciplinary diabetic limb preservation service between 01/2012 and 8/2020 who underwent first-time endovascular tibial revascularization for chronic limb-threatening ischemia. Diagnostic angiograms were reviewed to define the preferred target artery pathway and assign a GLASS stage to each treated limb. One-year LBP was calculated and compared across GLASS stages using Kaplan-Meier curves with log-rank tests and Cox proportional hazards models. RESULTS: We performed tibial revascularization in 96 limbs (5.2% rest pain, 56.3% ulcer, 37.5% gangrene), including isolated tibial interventions in 61.5% and tibial + femoropopliteal interventions in 38.5%. 15.6% of limbs were GLASS stage 1, 28.1% were GLASS stage 2, and 56.3% were GLASS stage 3. Overall, one-year LBP was 43.2 ± 6.3%, and did not differ significantly across GLASS stages (P = 0.42). The hazard ratio for failed LBP was 1.94 (95% CI 0.70-5.41) for GLASS stage 2 and 1.49 (95% CI 0.56-3.94) for GLASS stage 3 limbs (versus GLASS stage 1). When analyzed excluding the calcium modifier, LBP remained similar across GLASS stages (P = 0.72). Major amputation was uncommon, occurring in 9.3 ± 3.4% of limbs at one year, and did not significantly differ by GLASS stage (P = 0.98). CONCLUSION: The Global Anatomic Staging System did not predict limb-based patency following tibial endovascular interventions. Given the low major amputation rates in this cohort, anatomic complexity should not preclude endovascular limb salvage efforts below the knee.

True Aneurysms of Foot Arteries: A Case Report of a Young Patient.

BACKGROUND: Reports of true aneurysms of the lower leg are rare. Among them, cases involving young patients are all the more rare, and there are many unexplored aspects to this pathological condition. CASE PRESENTATION: This is a case of a 30-year-old woman who was referred by an orthopedic surgeon with a chief complaint of severe pain during walking and landing. Angiography revealed multiple aneurysms and arteriovenous fistulas in the posterior tibial artery and lateral plantar artery. We anastomosed the lateral plantar artery and interposed the posterior tibial artery using the great saphenous vein. CONCLUSIONS: Although aneurysms in the arteries of the feet are rare, multiple true arterial aneurysms were observed in the lower leg of a juvenile patient in the present case. Dilation of arteries other than the aneurysm was also observed, suggesting that arteriovenous fistula and arterial occlusion may have been the causes of the true aneurysm of the lower leg. This is a valuable finding, suggesting a cause of aneurysm other than age-related atherosclerotic changes.

Revascularization of multiple tibial arteries is not associated with improved limb salvage.

OBJECTIVE: We sought to determine the benefit of performing multiple tibial artery revascularization compared with single vessel revascularization for patients with chronic limb-threatening ischemia (CLTI). METHODS: We performed a single-center, retrospective cohort study of all patients with CLTI treated with below-the-knee endovascular intervention from 2012 to 2019. Group 1 included patients who had undergone single tibial artery revascularization. Group 2 included patients who had undergone multiple (two or more) tibial artery revascularization. More proximal disease, if present, was treated, in addition to the tibial disease. The primary endpoint was freedom from amputation. The secondary endpoints included the reintervention rates and all-cause mortality. RESULTS: A total of 527 limbs in 470 patients with CLTI (nonhealing ulcers, 62%; gangrene, 33%; and ischemic rest pain, 5%) were included in the present study. Of the 527 limbs, 245 (46%) had undergone single vessel revascularization and 282 (54%) had undergone multiple vessel revascularization. The mean follow-up was 19 ± 18 months. No difference was found in freedom from amputation between the two groups (68% vs 63%; P = .109). On multivariable analysis, the factors associated with amputation included dialysis (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.16-2.45), dyslipidemia (OR, 1.37; 95% CI, 0.96-1.94), and gangrene (OR, 2.08; 95% CI, 1.50-2.98). No differences were found in the reintervention rates between the two groups (21.2% vs 16.7%; P = .13). The overall survival rate was 73% in both study groups. CONCLUSIONS: The results from the present large, single-center study have demonstrated that multiple below-the-knee vessel revascularization is not associated with improved limb salvage compared with single vessel revascularization.

Preservation of Posterior Tibial Artery Flow Following Dissection With Associated Aneurysmal Degeneration in Ehlers-Danlos Syndrome Type IV Treated With Flow-Diverting Stent.

Ehlers-Danlos syndrome type IV (EDS-IV), the vascular type, is a rare genetic disorder affects the large and medium size arteries resulting in dissections, often with aneurysmal degeneration, intramural hematomas and pseudoaneurysms. Embolization or ligation is standard management for aneurysm formation. We present a case of an EDS-IV patient with a posterior tibial artery dissection with associated aneurysm successfully treated with Flow Diversion stent (FDS) preserving vessel patency and excluding the aneurysm. FDS technology allows for low profile, micro-catheter deliverable treatment options to exclude aneurysms in EDS-IV patients that are may be prone to spasm and dissection using more conventional stent graft technology.

Distal Retrograde Access for Infrainguinal Arterial Chronic Total Occlusions: A Prospective, Single Center, Observational Study in the Office-Based Laboratory Setting.

OBJECTIVE: To assess the safety and efficacy of retrograde arterial recanalization of infrainguinal CTOs in the OBL setting. METHODS: Consecutive patients who underwent interventions for lower extremity CTOs in the OBL setting by a single vascular surgeon were evaluated (January 2013-November 2017). If antegrade crossing was not possible, then a retrograde distal approach was used. Patient characteristics, CTO location, procedural time, contrast, anticoagulation and radiation doses and costs were recorded. Post-procedural complications were documented on post-procedure day 1 and 10-14 days post procedure. Three groups were compared: group 1-antegrade approach for femoropopliteal CTOs; group 2-antegrade approach for tibial CTOs, and; group 3-retrograde approach for femoropopliteal and tibial CTOs. RESULTS: Two hundred and thirty-seven patients were studied. In 39 (16.5%), the lesions could not be crossed. A successful antegrade approach was used in 185 of them, of which 69% (group 1, n = 128) patients had femoropopliteal CTOs and 31% (group 2, n = 57) had tibial CTOs. Fourteen patients (5.9%, group 3) were treated by retrograde distal approach. Group 3 patients received higher contrast doses than groups 1 and 2 (p = 0.01). However, patients in groups 1 and 2 received similar contrast doses. Group 3 patients had the highest operative time and treatment costs followed by group 1 and then group 2 (p = 0.01). Three femoral pseudoaneurysms were noted in group 1, and 2 in group 2. No complications were seen in group 3. CONCLUSIONS: Although the operative times, costs, radiation and contrast dose are higher with retrograde arterial access, it represents a safe and effective method for the crossing of CTO infrainguinal lesions in an ambulatory venue.

Tibial bypass in patients with intermittent claudication is associated with poor outcomes.

OBJECTIVE: Given that intermittent claudication (IC) rarely progresses to chronic limb-threatening ischemia and limb loss, safety and durability of elective interventions for IC are essential. Whether patients with IC benefit from tibial intervention is controversial, and data supporting its utility are limited. Despite endovascular therapy expansion, surgical bypass is still commonly performed. We sought to assess outcomes of bypass to tibial arteries for IC. METHODS: The Vascular Quality Initiative (2003-2018) was queried for infrainguinal bypasses performed for IC. Perioperative and 1-year outcomes were compared between bypasses constructed to tibial and popliteal arteries. RESULTS: Of 5347 infrainguinal bypasses, 1173 (22%) and 4184 (78%) were tibial and popliteal bypasses, respectively. Overall, mean age was 65 ± 10 years, and patients were often men (72%) and current smokers (42%). Tibial bypasses commonly targeted posterior tibial (40%), tibioperoneal trunk (23%), and anterior tibial (19%) arteries. Great saphenous vein was more often used for tibial bypass than for popliteal bypass (78% vs 54%; P < .001). Patients undergoing tibial compared with popliteal bypass more often had impaired ambulation and prior ipsilateral bypasses and were less often taking antiplatelets and statins (all P < .05). In the perioperative period, tibial bypass patients had longer postoperative length of stay (4.5 ± 3.5 vs 3.5 ± 2.8 days), more pulmonary complications (1.3% vs 0.6%), and higher return to the operating room (7% vs 4%; all P < .05). Perioperative myocardial infarction (1.2% vs 0.8%; P = .19), stroke (0.4% vs 0.4%; P = .91), and mortality (0.3 vs 0.3%; P = .86) rates were similar between the cohorts. At 1 year, tibial compared with popliteal bypasses exhibited lower freedom from occlusion/death (81% vs 89%; P < .001), ipsilateral major amputation/death (90% vs 94%; P < .001), and reintervention/amputation/death (73% vs 80%; P < .001), but patient survival was similar (96% vs 97%; P = .07). On multivariable analysis, tibial compared with popliteal bypass was independently associated with increased occlusion/death (hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.28-2.11; P < .001), major ipsilateral amputation/death (HR, 1.6; 95% CI, 1.12-2.19; P = .003), and ipsilateral reintervention/amputation/death (HR, 1.51; 95% CI, 1.28-1.79; P < .001), with similar patient survival. CONCLUSIONS: In patients with IC, tibial bypass was associated with poor outcomes, including major amputation. Surgeons should exhaust nonoperative therapies and present realistic outcome expectations to their patients before offering such intervention.

Percutaneous Deep Foot Vein Arterialization IVUS-Guided in No-Option Critical Limb Ischemia Diabetic Patients.

PURPOSE: To report our clinical experience with IVUS-guided percutaneous deep vein arterialization (pDVA) to treat chronic critical limb ischemia (cCLI) patients with no-endovascular or surgical options approach due to creation of an arteriovenous fistula (AVF). MATERIALS AND METHODS: In a 2 years period, 14 no-option cCLI patients were treated with percutaneous deep vein arterialization (pDVA) by creating an AVF with a IVUS-guided system between posterior tibial artery and its satellite deep vein. Technical success was defined as successful AVF creation and venous perfusion of the wound site. Patients' characteristics, procedure details, mortality and wound outcomes were assessed prospectively. RESULTS: Successful pDVA was successfully performed in all patients (mean age 82 years) without any procedural complications. Clinical improvement was achieved in all patients with resolution of rest pain, tissue formation of granulation tissue or both; only 3 major amputations were performed within the study period with a limb salvage rate of 78%. Median wound healing time was 4.8 months. CONCLUSION: pDVA is a safe and feasible revascularization technique alternative in no-option cCLI patients.

Tibial artery velocities in the diagnosis and follow-up of peripheral arterial disease.

Physiologic assessment of lower limb peripheral artery occlusive disease is based on indirect physiologic measurement of ankle-brachial systolic pressure index (ABI) and recording ultrasound tibial artery waveforms. Duplex ultrasound testing affords direct tibial artery imaging and assessment of pulsed-Doppler tibial artery waveforms, which is more accurate then measurement of ABI for peripheral artery occlusive disease severity assessment. Tibial artery peak systolic velocity (PSV) is of particular value in the evaluation of patients with incompressible tibial arteries producing a falsely elevated ABI. Calculation of the ankle-profunda index (average tibial artery PSV/proximal profunda femoris artery PSV) also correlates with ABI reduction and can be used as an additional measure of peripheral artery occlusive disease. Tibial artery PSVs can be used to supplement ABI as an objective outcome measure after peripheral arterial interventions, and this aspect of duplex scanning warrants further clinical research.

Pole Test and Ankle-Brachial Index by Using Doppler Ultrasound for Peripheral Arterial Disease in End-Stage Renal Disease Patients.

Peripheral arterial disease (PAD) causes great disability in end-stage renal disease (ESRD). Pole test is a simplified test utilizing the basis of Doppler ultrasound invented to correct false elevation in ankle-brachial index (ABI) in diabetic patients with severe calcification of the tibial artery. However, the role of pole test in ESRD patients is still unclear. The aim of this study was to explore the sensitivity, specificity, and overall utility of pole tests in such patients. One hundred and four patients were recruited and examined with 3 tests: pole test, ABI, and toe-brachial index, the latter serving as the gold standard. Receiver operating characteristic analysis was performed using SPSS version 22.0. The sensitivity, specificity, and other diagnostic values of ABI and pole tests were calculated. There were 104 ESRD patients enrolled. Pole tests showed to have low probability to provide accurate results (area under the curve = 0.505, standard error = 0.042). Low sensitivity of ABI (34.96%) can be observed in ESRD patients. Specificity, positive predictive value, and negative predictive value of ABI in all cases were, respectively, 85.91%, 81.13%, and 43.26%. It is concluded that pole test accuracy seemed to be limited in ESRD patients. ABI was found to be confounded by medial arterial calcification, resulting in low sensitivity as well. The results of this study permit the observation that an optimal tool for screening peripheral arterial disease in ESRD patients remains to be discovered.

Resistive index and peak systolic velocity for congenital talipes equinovarus: A color Doppler ultrasonography study.

OBJECTIVES: This study aims to investigate whether resistive index (RI) and peak systolic velocity (PSV) are suitable parameters to determine if a clubfoot differs from feet of the normal population. PATIENTS AND METHODS: Fifty-four feet of 27 clubfoot patients (22 males, 5 females; mean age 30.4±16.3 months; range, 5 to 72 months) were included in this retrospective study conducted between December 2017 and January 2019. Twenty-seven feet were conservatively treated, 19 had surgical treatment, and eight feet were healthy in patients with unilateral clubfoot. In addition, 22 feet of 11 normal controls (6 males, 5 females; mean age 33.4±15.3 months; range, 15 to 60 months) were studied. Color Doppler ultrasonography examinations were performed to evaluate the three major arteries of the leg and foot: dorsalis pedis (dp), tibialis posterior (tp), and popliteal (pop). Color filling, flow direction, spectral analysis, velocity, and RI were examined. RESULTS: With the exception of the dp artery RI, the PSV and RI values for all arteries differed significantly from those of the control group. There were no significant differences among the conservative, surgical, and healthy groups, while there were significant differences between each of the treated groups and the control group. Tibialis posterior artery PSV and pop artery RI were the best parameters to identify clubfoot and the cut-off points were 54 cm/second and 0.77, respectively. CONCLUSION: Peak systolic velocity and RI may be accepted as important parameters for identification of clubfoot deformity. Tibialis posteriorartery PSV and pop artery RI are the best- detailed parameters for this examination.

Protamine sulfate use during tibial bypass does not appear to increase thrombotic events or affect short-term graft patency.

OBJECTIVES: While the use of protamine sulfate as a heparin reversal agent has been extensively reviewed in patients undergoing carotid endarterectomy and coronary artery bypass grafting, there is a lack of literature on protamine's effects on lower extremity bypasses. The purpose of this study was to determine the risk of protamine sulfate dosing after tibial bypass on thrombotic or bleeding events, including early bypass failure. METHODS: We performed a retrospective review of our institutional database for patients undergoing primary distal peripheral bypass from January 2009 through December 2015 (contralateral bypass was considered to be a new primary bypass). Primary endpoints include composite thrombotic events (myocardial infarction, stroke, amputation at 30 days and patency less than 30 days) and composite bleeding events (bleeding or transfusion). RESULTS: A total of 152 tibial or peroneal bypasses in 136 patients with critical limb ischemia were identified. Of these, 78 (57.4%) patients received protamine sulfate intraoperatively and 58 (42.6%) did not. There were no differences in composite thrombotic or hemorrhagic outcomes. Protamine use had no effect on the rates of perioperative MI (9.0% versus 3.5%, p = 0.20), stroke (1.3% versus 1.7%, p = 0.83), or perioperative mortality (5.1% versus 3.5%, p = 0.64). There was no significant difference in composite post-operative bleeding events (20.7% versus 14.1%, p = 0.31) or composite thrombotic events (17.2% versus 18.0%, p = 0.91). Patients who received protamine undergoing bypass with non-autogenous conduit had significantly higher-recorded median operative blood loss (250 mL versus 150 mL, p = 0.0097) and median procedure lengths (265 min versus 201 min, p = 0.0229). No difference in 30-day amputation-free survival was noted (91.0% versus 91.4%, p = 0.94). Follow-up Kaplan-Meier estimation did not demonstrate a difference in 30-day patency (91.7% versus 88.5%, p = 0.52). CONCLUSIONS: Heparin reversal with protamine sulfate after tibial or peroneal bypass grafting is not associated with higher cardiovascular morbidity, bypass thrombosis, amputation, or mortality. Additionally, there was no statistically significant difference in post-operative bleeding or thrombosis complications for patients who did not receive protamine, although the findings are suggestive of a potential difference in a more adequately powered study. Our results suggest that protamine sulfate is safe for intraoperative use without increased risk of thrombotic complications or early tibial bypass graft failure.

Implications of early failure of isolated endovascular tibial interventions.

BACKGROUND: Endovascular tibial interventions for chronic limb-threatening ischemia are frequent, but the implications of early failure (≤30 days) of an isolated tibial intervention are still unclear. The aim of this study was to examine the patient-centered outcomes after early failure of isolated tibial artery intervention. METHODS: A database of patients undergoing lower extremity endovascular interventions between 2007 and 2017 was retrospectively queried. Patients with chronic limb-threatening ischemia (Rutherford classes 4, 5, and 6) were selected, and failures within 30 days were identified. Lack of technical success at the time of the procedure was an exclusion. Intention-to-treat analysis by patient was performed. Patient-oriented outcomes of clinical efficacy (absence of recurrent symptoms, maintenance of ambulation, and absence of major amputation), amputation-free survival (survival without major amputation), and freedom from major adverse limb events (MALEs; above-ankle amputation of the index limb or major reintervention [new bypass graft, jump or interposition graft revision]) were evaluated. RESULTS: There were 1779 patients (58% male; average age, 65 years; 2898 vessels) who underwent tibial intervention for chronic limb-threatening ischemia; 284 procedures (16%) were early failures. In the early failure group, 124 cases (44%) were considered immediate (<24 hours), and 160 cases (56%) failed within the first 30 days after intervention. The two modes of failure were hemodynamic failure (47%) and progression of chronic limb-threatening ischemia (53%). Bypass after early failure was successful in patients with adequate vein, target vessel of ≥3 mm, and good inframalleolar runoff. Progression of symptoms was associated with major amputation in patients with Rutherford class 5 and class 6 disease. Presentation with diabetes and end-stage renal disease were identified as independent clinical predictors for early failure. Lesion calcification, reference vessel diameter <3 mm, lesion length >300 mm, and poor inframalleolar runoff were identified as independent anatomic predictors for early failure and increased MALEs. Early failure was predictive of poor long-term clinical efficacy (11% ± 9% vs 39% ± 8% at 5 years, mean ± standard error of the mean, early vs no early failure; P = .01) and amputation-free survival (16% ± 9% vs 47% ± 9% at 5 years, mean ± standard error of the mean, early vs no early failure; P = .02). CONCLUSIONS: Both clinical and anatomic factors can predict early failure of endovascular therapy for isolated tibial disease. Early failure significantly increases 30-day major amputation and 30-day MALEs and is associated with poor long-term patient-centered outcomes.

Multivessel tibial revascularization does not improve outcomes in patients with critical limb ischemia.

OBJECTIVE: Multivessel tibial revascularization for critical limb ischemia (CLI) remains controversial. The purpose of this study was to evaluate single vs multiple tibial vessel interventions in patients with multivessel tibial disease. We hypothesized that there would be no difference in amputation-free survival between the groups. METHODS: Using the Vascular Quality Initiative registry, we reviewed patients undergoing lower extremity endovascular interventions involving the tibial arteries. Patients with CLI were included only if at least two tibial vessels were diseased and adequate perioperative data and clinical follow-up were available for review. The primary outcome was amputation-free survival. RESULTS: There were 10,849 CLI patients with multivessel tibial disease evaluated from 2002 to 2017; 761 limbs had adequate data and follow-up available for review. Mean follow-up was 337 ± 62 days. Of these, 473 (62.1%) underwent successful single-vessel tibial intervention (group SV), whereas 288 (37.9%) underwent successful multivessel (two or more) intervention (group MV). Patients in group MV were younger (69.1 vs 73.2 years; P < .001), with higher tobacco use (29.5% vs 18.2%; P < .001). Group SV more commonly had concurrent femoral or popliteal inflow interventions (83.7% vs 78.1%; P = .05). Multivessel runoff on completion was significantly greater for group MV (99.9% vs 39.9%; P < .001). No differences were observed between group SV and group MV for major amputation (9.0% and 7.6%; P = .6), with similar amputation-free survival at 1 year (90.6% vs 92.9%; P = .372). In a multivariate Cox model, loss of patency was the only significant predictor of major amputation (hazard ratio, 5.36 [2.7-10.6]; P = .01). A subgroup analysis of 355 (46.6%) patients with tissue loss data showed that tissue loss before intervention was not predictive of future major amputation. CONCLUSIONS: In the Vascular Quality Initiative registry, patients with CLI and occlusive disease involving multiple tibial vessels did not appear to have a limb salvage benefit from multiple tibial revascularization compared with single tibial revascularization.