Outcomes of Peripheral Vascular Interventions via Retrograde Pedal Access for Chronic Limb-Threatening Ischemia in a Multicenter Registry

Abstract

Purpose: To describe the use and 1-year outcomes of retrograde pedal access during peripheral vascular interventions (PVI) for chronic limb-threatening ischemia (CLTI). Materials and Methods: From October 2016 to September 2017, 159 patients (mean age 71±10 years; 112 men) undergoing PVI via retrograde pedal access were enrolled in the multicenter Vascular Quality Initiative (VQI) registry. The pedal access approach included retrograde femoral (40%), antegrade femoral (26%), retrograde to antegrade femoral (22%), and pedal only (11%). A comparator group of 1972 patients (mean age 69±12 years; 1129 men) having a contralateral retrograde femoral access was established for propensity matching, which resulted in 156 patients per group. Procedure characteristics, technical success, and access site complications were compared. Major adverse limb events (MALE) and amputation-free survival (AFS) at 1 year were analyzed using the Kaplan-Meier method and Cox proportional hazard models to calculate hazard ratios (HR) and 95% confidence intervals (CI). Results: Technical failure was similar for retrograde femoral and pedal access (7% vs 13%, p=0.07). Complications were rare and included access site hematoma (2 vs 5, p=0.32) and target artery thrombosis (0 vs 2) for the femoral vs pedal access groups, respectively. The rates of MALE at 1 year were significantly lower after retrograde femoral access (24%) compared with pedal access (38%; log-rank p=0.01; HR 1.95, 95% CI 1.15 to 3.30). AFS estimates at 1 year were similar: 86% for retrograde femoral and 83% for pedal access (log-rank p=0.37; HR 1.32, 95% CI 0.73 to 2.39), as were major amputation estimates: 10% for retrograde femoral access and 13% for pedal access group (log-rank p=0.21; HR 1.58, 95% CI 0.77 to 3.26). Conclusion: In this analysis of multicenter registry data, retrograde pedal access in patients with CLTI had similar technical success and early complications in comparison with traditional contralateral retrograde femoral access. The rates of MALE were higher after pedal access but AFS was similar, indicating a tradeoff between limb salvage and repeat interventions.

Keywords

amputation chronic limb-threatening ischemia limb salvage pedal access peripheral vascular intervention registry

Introduction

Advanced peripheral artery disease manifesting as chronic limb-threatening ischemia (CLTI) remains a challenging clinical problem, with 20% mortality and a 30% rate of major amputation at 1 year.^1,2 With the increase in the endovascular first approach, alternative forms of access have been developed to expand the options for the delivery of peripheral devices. Described in 1990 by Iyer and colleagues,³ retrograde tibial access is a revascularization option in selected patients. Since that time there have been several case reports and single-center series describing this technique.^4–8 A prospective, nonrandomized, multicenter study reported outcomes only to 30 days.⁹ Because the early success by pioneers and centers of excellence may not be replicated in real-world practice, this study analyzed the real-world use and outcomes of retrograde pedal access for peripheral vascular interventions (PVI) in patients with CLTI enrolled in a multicenter national quality improvement registry.

Materials and Methods

Study Design

This was a retrospective cohort study of prospectively collected data from the Vascular Quality Initiative (VQI) PVI Registry. The VQI is an Agency for Health Research and Quality–designated Patient Safety Organization that registers perioperative and 1-year follow-up data on vascular procedures to improve the quality of patient care across a spectrum of vascular procedures. Participants in the VQI PVI registry include vascular surgeons (53%), cardiologists (20%), interventional radiologists (17%), general surgeons (5%), and other (5%) specialists. Further information about the registry has been previously published.¹⁰

The VQI PVI database was queried for all patients undergoing elective or urgent retrograde pedal access for PVI for CLTI, defined as ischemic rest pain or tissue loss, from October 2016 to September 2017. Infrainguinal interventions on the common femoral, superficial femoral, popliteal, tibial, and peroneal arteries were included. Interventions on the aorta and iliac arteries were excluded. Only percutaneous procedures were included with exclusion of concomitant bypass or femoral endarterectomy procedures. The study protocol followed the guidelines in the Declaration of Helsinki and was reviewed by the Institutional Review Board at the University of Vermont Medical Center, which deemed it to be exempt from patient consent.

Patient Samples and Propensity Score Matching

In the VQI database, there were 453 CLTI patients who underwent a PVI by retrograde pedal access in 458 limbs. Of these, 206 (45%) had follow-up data recorded, but 47 were missing data on amputation, for a total of 159 limbs. In the pedal access group, the approach was retrograde femoral (40%), antegrade femoral (26%), retrograde to antegrade femoral (22%), and pedal only (11%). Crossover from one approach to another occurred in 2 patients (one from a combined contralateral retrograde femoral and ipsilateral pedal to contralateral retrograde femoral and a second from ipsilateral pedal to contralateral retrograde femoral).

A comparator group of 1972 patients (mean age 69±12 years; 1129 men) having a contralateral retrograde femoral access was established based on the following variables: age, male gender, race, body mass index (BMI), presence of congestive heart failure (CHF), dialysis dependence, prior bypass, prior major or minor amputation, urgent operation, tissue loss as indication for the procedure, arterial segment treated, and living status. Characteristics of the 2 access cohorts are presented in Table 1.

Table 1.

Characteristics of Patients Treated by Retrograde Pedal and Contralateral Retrograde Femoral Access.^a

Variable	Entire Cohort			Propensity-Matched Groups
Variable	Pedal Access (n=159)	Retrograde Femoral Access (n=1972)	p	Pedal Access (n=156)	Retrograde Femoral Access (n=156)	p
Age, y	71±10	69±12	0.03	71±10	71±12	0.46
Men	112 (70)	1129 (57)	0.001	110 (71)	117 (75)	0.30
Race
White, non-Hispanic	101 (64)	1329 (67)	0.002	100 (64)	109 (70)	0.42
Black, non-Hispanic	24 (15)	407 (21)		24 (15)	21 (13)
Other	34 (21)	236 (12)		32 (21)	26 (17)
BMI, kg/m²
<20	13 (8)	119 (6)	0.05	12 (8)	11 (7)	0.86
20–30	98 (62)	1066 (54)		96 (62)	95 (61)
>30	48 (30)	784 (40)		48 (31)	50 (32)
Living status (not home)	12 (8)	144 (7)	0.91	12 (8)	8 (5)	0.32
CHF
None	123 (77)	1461 (74)	0.11	102 (77)	121 (78)	0.95
History, asymptomatic	16 (10)	314 (16)		16 (10)	15 (10)
Symptomatic	20 (13)	197 (10)		20 (13)	20 (13)
Creatinine, mg/dL
≤1.8	126 (80)	1565 (80)	0.49	124 (79)	134 (86)	0.43
>1.8	8 (5)	142 (7)		8 (5)	5 (3)
Dialysis	24 (15)	259 (13)		24 (15)	17 (11)
Rutherford category			0.04			0.16
4	39 (25)	529 (28)		37 (26)	37 (26)
5	57 (37)	834 (44)		52 (36)	66 (46)
6	58 (38)	531 (28)		54 (38)	40 (28)
Diabetes	114 (72)	1402 (71)	0.87	113 (72)	109 (70)	0.60
Prior bypass	42 (26)	422 (21)	0.14	41 (26)	38 (24)	0.70
Prior amputation	61 (38)	494 (25)	<0.001	60 (38)	51 (33)	0.19
Urgency	28 (18)	437 (22)	0.18	26 (17)	21 (13)	0.42
Arteries treated
SFA-popliteal	93 (59)	1507 (77)	<0.001	92 (59)	92 (59)	>0.99
Tibial-peroneal	65 (41)	462 (23)		64 (41)	64 (41)
FP TASC class			<0.001			0.02
A	10 (13)	357 (30)		5 (10)	17 (35)
B	13 (16)	333 (28)		9 (19)	16 (33)
C	9 (11)	260 (22)		5 (10)	6 (13)
D	47 (59)	225 (1)		29 (60)	9 (19)
SFA CTO length, mm	21.5±15.0	16.5±15.0	0.006	21.9±15.1	14.3±10.3	0.003
FP calcification			0.03			0.73
None	19 (23)	401 (30)		15 (26)	21 (37)
Focal	3 (4)	94 (7)		2 (4)	3 (5)
Mild	8 (10)	158 (12)		6 (11)	5 (9)
Moderate	17 (20)	312 (24)		11 (19)	14 (25)
Severe	36 (43)	359 (27)		23 (40)	14 (25)
Tibial arteries treated			0.63			0.75
1	45 (69)	296 (64)		31 (67)	26 (57)
2	17 (26)	132 (29)		12 (26)	18 (39)
3	2 (3)	30 (6)		2 (4)	2 (4)
4	1 (2)	4 (1)		1 (2)	0 (0)
Tibial CTO length, mm	18.8±10.8	21.4±24.6	0.21	18.1±11.5	20.7±17.6	0.55
Tibial runoff vessels			0.91			0.54
0	3 (4)	51 (4)		3 (5)	4 (7)
1	31 (38)	478 (34)		22 (38)	16 (28)
2	26 (32)	484 (34)		18 (31)	17 (29)
3	22 (27)	396 (28)		15 (26)	21 (36)

Abbreviations: BMI, body mass index; CHF, congestive heart failure; CTO, chronic total occlusion; FP, femoropopliteal; SFA, superficial femoral artery; TASC, TransAtlantic Inter-Society Consensus.

Continuous data are presented as the mean ± standard deviation; categorical data are given as the number (percentage).

Propensity scores were built through a binary logistic regression using the following baseline covariates: age, sex, race, BMI, living status, creatinine, urgency, indication, arteries treated, and prior history of CHF, bypass, and/or amputation. A 1:1 nearest neighbor matching was performed without replacement based on a greedy matching algorithm with a caliper range of 0.25, resulting in 156 matched patients (Table 1).

Outcomes

The main outcome was major adverse limb events (MALE), defined as major amputation or reintervention at 30 days and at 1-year follow-up. Secondary outcomes included (1) amputation-free survival (AFS), defined as absence of above-the-ankle amputation of the index limb or death from any cause at 30 days and 1 year and (2) in-hospital major adverse cardiac events (MACE) defined as any postoperative myocardial infarction or postoperative death. In addition, technical success and access site complications (hematoma, access site occlusion, and target vessel thrombosis) were compared between matched groups.

Statistical Analysis

Statistical methods to compare the variables of interest between the matched groups were the McNemar chi-square test for categorical variables and a paired t test for continuous variables. Survival was estimated using the Kaplan-Meier method (differences between groups were analyzed with the log-rank test) and Cox proportional hazards regression modeling stratified by matched sets to generate hazard ratios (HR) and 95% confidence intervals (CI). The threshold of statistical significance was p<0.05. All analyses were conducted using SAS statistical software (version 9.4; SAS Institute, Inc, Cary, NC, USA).

Results

Patients treated via pedal access in the unmatched cohort were older (71 vs 69 years, p=0.03) and were more likely to have had a prior minor or major amputation (38% vs 25%, p<0.001) or to have treatment of the tibial-peroneal vessels (41% vs 23%, p<0.001) than patients in the retrograde femoral access group (Table 1). The only significant differences between the propensity-matched groups were the length of chronic total occlusions in the superficial femoral artery and the TransAtlantic Inter-Society Consensus class, which were not included in the propensity matching (Table 1).

In the matched cohorts, the anterior tibial (89, 57%) was the most common artery used for access compared to the tibial peroneal trunk (25, 16%), posterior tibial (48, 31%), and peroneal arteries (17, 11%). Ultrasound guidance was utilized in 143 (92%) of the pedal access procedures, fluoroscopy in 7 (4%), and no imaging guidance in 6 (4%) cases (Table 2). The types of tibial interventions were balloon angioplasty (89% vs 99%), stent (11% vs 7%), and atherectomy (33% vs 23%) for pedal access vs retrograde femoral access procedures, respectively.

Table 2.

Procedure Characteristics in the 156 Matched Pairs.

	Pedal Access	Retrograde Femoral Access
Access guidance
Ultrasound	143 (92)	111 (71)
Fluoroscopy	7 (4)	20 (13)
None	6 (4)	25 (16)
Sheath size, F	4.5±0.9	5.9±0.6
Segment treated
Femoropopliteal	92 (59)	92 (59)
Infrapopliteal	130 (83)	100 (64)
Tibial intervention type
Balloon angioplasty	116 (89)	99 (99)
Stent	14 (11)	7 (7)
Atherectomy	43 (33)	23 (23)

Continuous data are presented as the mean ± standard deviation; categorical data are given as the number (percentage).

Technical failure was not significantly different at 7% for femoral access and 13% for pedal access (p=0.07) in the matched groups. For patients without diabetes (14 pairs), technical failure was the same (n=1) for retrograde femoral and pedal access. For those with diabetes (80 pairs), the technical failure rates were significantly lower for retrograde femoral access (5%, 4/80) vs 19% (15/80) for pedal access (p=0.008).

Complications were rare and included access site hematoma (1% vs 3%, p=0.32) and target artery thrombosis (0 vs 1%) for the retrograde femoral vs pedal access groups, respectively. MALE occurred in 2 (1%) patients at 30 days in the retrograde femoral group vs 8 (5%) in the pedal access group (log-rank p=0.06; HR 4.00, 95% CI 0.85 to 18.84).

The rates of MALE at 1 year were 24% in the retrograde femoral group and 38% in the pedal access group (HR 1.95, 95% CI 1.15 to 3.30). Kaplan-Meier estimates for freedom from MALE at 1 year for the retrograde femoral and pedal access groups were 76% (95% CI 68% to 83%) and 62% (95% CI 52% to 70%), respectively (log-rank p=0.01; Figure 1A). AFS at 1 year was 86% in the retrograde pedal group and 83% in the pedal access group (HR 1.32, 95% CI 0.73 to 2.39). Kaplan-Meier estimates for AFS at 1 year for retrograde femoral and pedal access were 86% (95% CI 80% to 91%) and 83% (95% CI 76% to 88%), respectively (log-rank p=0.37; Figure 1B). Analysis of the propensity score–matched cohort revealed similar major amputation rates of 10% (16/156) for retrograde femoral access and 13% (21/156) for pedal access (HR 1.58, 95% CI 0.77 to 3.26, p=0.21) at a median follow-up of 10.8 months. Kaplan-Meier estimates for freedom from major amputation at 1 year for retrograde femoral and pedal access were 88% (95% CI 81% to 93%) and 85% (95% CI 77% to 90%), respectively (Figure 1C).

Figure 1.

Kaplan-Meier analyses of (A) freedom from major adverse limb events, (B) amputation-free survival, and (C) freedom from major amputation after retrograde femoral vs pedal access.

In-hospital MACE rates were similar between the pedal access (9, 6%) and the retrograde femoral (8, 5%) groups (p=0.81). In the propensity-matched groups, the raw reintervention rates at 1 year were 21% for pedal access and 11% for retrograde femoral access (p=0.02).

The mean total length of stay (LOS) was similar between groups at 3.2 vs 2.6 days in pedal and retrograde femoral groups, respectively (p=0.34). The mean postoperative LOS was similar at 1.9 vs 1.5 days in the pedal and retrograde femoral groups (p=0.38).

Discussion

Patients with CLTI who are not candidates for a surgical bypass or are unable to be revascularized through a traditional percutaneous approach may benefit from alternative access routes such as retrograde pedal access. Bazan et al¹¹ describe some advantages of utilizing a pedal approach, including easier crossability, decreased likelihood of entering collateral vessels due to their caudal angle, and improved pushability through the smaller-diameter tibial vessels. The approach may also have a safety advantage in the patients with prior bifurcated aortic grafts, hostile groin, or morbid obesity.¹¹ Additionally, pedal access has been successfully used as a bailout procedure after complications from a traditional femoral approach in an SFA intervention.¹²

El-Sayed et al¹³ performed a retrospective study of patients with tibial vessel disease who had failed antegrade revascularization. They achieved successful revascularization in 67% of the patients, with an 88% limb salvage rate at 1 year. In addition to the efficacy of the approach, they reported a 5% 30-day MACE rate and 5% 30-day MALE, which was similar in our study. In another single-center retrospective study, Kaushal et al¹⁴ reported a 63% technical success rate and a 79% limb salvage rate with short-term follow-up of only 5 months. Other authors in single-center studies have similarly supported the safety and effectiveness of this approach.^15–19

Our study determined that a pedal approach is a safe alternative to a contralateral retrograde femoral approach, with no significant difference in technical failure or access site complications, specifically hematoma or target vessel occlusion or thrombosis. Despite patients undergoing pedal access being older and having a greater proportion of tibial-peroneal disease, there was no difference in major amputation rates in the unmatched analysis or in the propensity-matched groups. The pedal access group had a higher rate of MALE at 30 days and 1 year but comparable AFS to the retrograde femoral group. This was due to a reintervention rate in the pedal access group at 1 year nearly twice that in the femoral access group.

Limitations

Although the VQI database is a prospectively maintained database with claims-based auditing of procedure capture, there is no independent third party group responsible for auditing all data, and follow-up data were not available for all patients. Additional study with registry matched to Medicare claims is planned to address this limitation. Despite these shortcomings, the VQI provides the best available granular data on real world practice across a variety of specialties.

Conclusion

In this multicenter registry analysis, retrograde pedal access in patients with CLTI appears safe and effective in comparison to traditional contralateral retrograde femoral access, with similar technical success, early complications, and major amputations within 1 year. There was a higher reintervention rate in the pedal access group but no difference in AFS, suggesting a tradeoff between limb salvage and repeat interventions.

Footnotes

Authors’ Note

This study was presented at Society for Vascular Surgery–Vascular Annual Meeting (June 14, 2019; National Harbor, MD, USA).

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Daniel J. Bertges

References

Davies

MG.

Critical limb ischemia: epidemiology. Methodist DeBakey Cardiovasc J. 2012;8:10–14.

Kudo

Chandra

Kwun

, et al. Changing pattern of surgical revascularization for critical limb ischemia over 12 years: endovascular vs. open bypass surgery. J Vasc Surg. 2006;44:304–313.

Iyer

Dorros

Zaitoun

, et al. Retrograde recanalization of an occluded posterior tibial artery by using a posterior tibial cutdown: two case reports. Cathet Cardiovasc Diagn. 1990;20:251–253.

Spinosa

Harthun

Bissonette

, et al. Subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) for subintimal recanalization to treat chronic critical limb ischemia. J Vasc Interv Radiol. 2015;16:37–44.

Mustapha

Saab

McGoff

, et al. Tibio-pedal arterial minimally invasive retrograde revascularization in patients with advanced vascular disease: the TAMI technique. Catheter Cardiovasc Interv. 2014;83:987–994.

Ruzsa

Bellavics

Nemes

, et al. Combined transradial and transpedal approach for femoral artery interventions. JACC Cardiovasc Interv. 2018;11:1062–1071.

Montero-Baker

Schmidt

Braunlich

, et al. Retrograde approach for complex popliteal and tibioperoneal occlusions. J Endovasc Ther. 2008;15:594–604.

Komshian

Cheng

Farber

, et al. Retrograde popliteal access to treat femoropopliteal artery occlusive disease. J Vasc Surg. 2018;68:161–167.

Walker

Mustapha

Zeller

, et al. Tibiopedal access for crossing of infrainguinal artery occlusions: a prospective multicenter observational study. J Endovasc Ther. 2016;23:839–846.

10.

Cronenwett

Kraiss

Cambria

RP.

The Society for Vascular Surgery Vascular Quality Initiative. J Vasc Surg. 2012;55:1529–1537.

11.

Bazan

Donovan

, et al. Retrograde pedal access for patients with critical limb ischemia. J Vasc Surg. 2014;60:375–381.

12.

Amro

Gabi

Elhamdani

, et al. Retrograde tibiopedal access as a bail-out procedure for endovascular intervention complications. Case Rep Vasc Med. 2016;2016:7519748.

13.

El-Sayed

Bennett

Loh

, et al. Retrograde pedal access and endovascular revascularization: a safe and effective technique for high-risk patients with complex tibial vessel disease. Ann Vasc Surg. 2016;31:91–98.

14.

Kaushal

Roche-Nagle

Tan

, et al. Outcomes at a single center after subintimal arterial flossing with an antegrade-retrograde intervention for critical limb ischemia. J Vasc Surg. 2018;67:1448–1454.

15.

Sabri

Hendricks

Stone

, et al. Retrograde pedal access technique for revascularization of infrainguinal arterial occlusive disease. J Vasc Interv Radiol. 2015;26:29–38

16.

Botti

Ansel

Silver

, et al. Percutaneous retrograde tibial access in limb salvage. J Endovasc Ther. 2003;10:614–618.

17.

Kwan

Shah

Amoroso

, et al. Feasibility and safety of routine transpedal arterial access for treatment of peripheral artery disease. J Invasive Cardiol. 2015;27:327–330.

18.

Ruzsa

Nemes

Bansaghi

, et al. Transpedal access after failed anterograde recanalization of complex below-the-knee and femoropopliteal occlusions in critical limb ischemia. Catheter Cardiovasc Interv. 2013;83:997–1007.

19.

Welling

RHA

Bakker

Scheinert

, et al. Below-the-knee retrograde access for peripheral interventions: a systematic review. J Endovasc Ther. 2018;25:345–352.