CathMasters hosts Dr. Amit Goyal, Dr. Li Pang, and Dr. Nazli Okumus discuss the evidence base for percutaneous transaxillary large-bore arterial access and closure with expert faculty Dr. Rajiv Tayal. Approximately 5% of US TAVR cases require alternative access despite lower-profile devices, and with expanding indications for TAVR and mechanical circulatory support (MCS), the absolute number of patients needing non-femoral large-bore access is rising. This “Data to Delivery” episode reviews the comparative outcomes of transaxillary access for TAVR and MCS, the stroke signal and laterality debate, vascular complications of percutaneous versus surgical approaches, brachial plexus injury risk, dwell-time considerations for axillary MCS, and the learning curve for this technique.

CathMasters is for educational purposes only.

CathMasters is for educational purposes only. Music by Elijah K from Pixabay

Pearls

1. The second segment of the axillary artery is the preferred access site because it is devoid of brachial plexus elements on its anterior surface, is accessible to surgical bailout, and is distant enough from the chest cavity to minimize pneumo/hemothorax risk — a transpectoral approach through pectoralis minor under ultrasound guidance targets this segment (SCAI Position Statement, Seto et al. 2022).
2. “Bidirectional control is the fundamental principle of large-bore alternative access.” Maintain a bailout wire (from the ipsilateral radial or femoral artery) in addition to the wire through the large-bore sheath. This enables proximal balloon tamponade (“dry closure”) and rapid covered stent deployment if catastrophic bleeding occurs.
3. Stroke is the Achilles’ heel of transaxillary TAVR — rates are consistently 6–8% across registries (TVT Registry, Hostile Registry, ACCESS study) and appear independent of valve type, laterality, surgical vs. percutaneous approach, or center experience. The 2025 SCAI Consensus Statement notes that other extrathoracic access techniques (transcarotid, transcaval) should be favored over transaxillary when stroke risk is a primary concern.
4. More vascular complications ≠ more bleeding with percutaneous access. The TVT Registry propensity match showed percutaneous transaxillary access had double the major vascular complications vs. surgical cutdown (3.0% vs. 1.5%), but Southmayd’s systematic review found dramatically less major bleeding with percutaneous access (2.7% vs. 18%). This paradox is partly definitional: covered stent placement counts as a vascular complication in percutaneous series but conduit/graft use does not in surgical series.
5. Axillary Impella enables early ambulation and device stability — the ARMS Registry (102 patients, 10 centers) demonstrated feasibility with complication rates comparable to transfemoral Impella. Devices have been maintained for >14 days percutaneously, though prolonged dwell times increase thrombus risk and may warrant higher ACT targets. After removing the peel-away sheath, the repositioning sheath downsizes to 9F at the tip — leaving the peel-away sheath in place risks a 5–6F gap that promotes thrombus formation and embolization.

Notes

1. Why Transaxillary Access Matters Now

• Approximately 25% of TAVR patients have peripheral arterial disease (PAD), and the 2025 SCAI Expert Consensus Statement reports that 4.7% of US TAVR cases require alternative (non-femoral) access despite lower-profile delivery systems.
• With TAVR expanding into lower-risk populations and MCS use increasing (high-risk PCI, cardiogenic shock), the absolute demand for non-femoral large-bore access is growing.
• Transaxillary access is versatile: it can be performed percutaneously under conscious sedation without general anesthesia or OR activation, and can be deployed emergently (e.g., cardiogenic shock) or electively.
• The 2025 SCAI Consensus Statement notes that transaxillary access may carry a higher risk for neurologic complications and recommends that other extrathoracic techniques be favored when feasible.

2. Outcomes: Transaxillary vs. Transfemoral TAVR

• Propensity-matched studies show comparable 30-day and 1-year mortality between transaxillary and transfemoral TAVR (Gleason et al., CoreValve trial; Dahle et al., TVT Registry; Kindzelski et al., Cleveland Clinic series).
• Procedural success rates for transaxillary TAVR are high (91–100% across observational studies).
• The transaxillary approach has emerged as the most common alternative to transfemoral access, surpassing transapical and transaortic routes, which carry higher mortality and bleeding rates.

3. The Stroke Signal

• Stroke rates with transaxillary TAVR are consistently elevated at 6–8% across multiple registries:
  • TVT Registry (Dahle et al.): 6.1% at 30 days with SAPIEN 3
  • CoreValve Extreme Risk Pivotal Trial: 7.5%
  • Hostile Registry (Palmerini et al.): 5.9% for transalternative access (92% transaxillary)
  • ACCESS Study: 8.0% overall (4.0% debilitating)
• The 2025 SCAI Consensus concludes that elevated stroke rates appear to be a “class effect” of transaxillary access, independent of valve selection, laterality, surgical vs. percutaneous approach, or center experience.
• Proposed mechanisms include: (a) sheath-to-artery ratio effects in a smaller vessel (~6.2 mm average diameter vs. ~8.5 mm for femoral); (b) atherosclerotic embolization during catheter exchanges; (c) right-sided access crossing the innominate artery with inline flow to the right carotid; (d) vertebral artery flow interruption by the large-bore sheath.
• Laterality: In the Hostile Registry, right transaxillary stroke was 6.3% vs. 3.7% left, but this difference was not statistically significant (HR 1.14; 95% CI 0.37–3.57; p = 0.82). The ACCESS study similarly found no significant difference by laterality. Left-sided access is generally preferred when feasible, as the sheath may create a partial “embolic shield” across the brachiocephalic artery.
• Compared with transcarotid and transcaval access, transaxillary access has consistently higher stroke rates in propensity-matched analyses. Lederman et al. reported a five-fold reduction in stroke/TIA with transcaval vs. transaxillary access (2.9% vs. 13.2%).

4. Vascular Complications: Percutaneous vs. Surgical Cutdown

• TVT Registry propensity match (Chung et al., 2022; n = 4,219): Percutaneous transaxillary access had higher major vascular complications (3.0% vs. 1.5%; p = 0.02) but similar life-threatening bleeding (0.3% vs. 0.1%; p = 0.31) compared with surgical cutdown. Percutaneous access was associated with less ICU utilization and more use of conscious sedation.
• Southmayd et al. systematic review (2020): Percutaneous large-bore axillary access had dramatically less major bleeding than surgical cutdown (2.7% vs. 18%).
• The apparent paradox (more vascular complications but less bleeding) is partly definitional: covered stent placement is classified as a vascular complication in percutaneous series, whereas conduit/graft use in surgical cutdown is not.
• Dry closure is the key hemostasis strategy: deploy Perclose devices, and if there is residual bleeding, inflate a balloon proximal to the arteriotomy for tamponade while deploying a covered stent (Viabahn preferred for superior apposition and crush resistance). Covered stent patency in non-diseased axillary arteries is excellent long-term.
• The axillary artery has a rich collateral network (subscapular contributories); vascular surgery data suggest that ligation of the artery in the appropriate segment does not cause significant upper extremity ischemia.

5. Other Complications: Brachial Plexus Injury, Pneumo/Hemothorax

• Brachial plexus injury was historically the most feared complication (rates as high as 15–20% in the 1970s–80s) when access was obtained in the third segment of the artery (armpit, arm abducted, palpation-guided). The neurovascular bundle is enclosed in a fascial sheath with the artery and vein in this segment, making hematoma-related nerve compression common.
• Modern transpectoral access to the second segment under ultrasound guidance has dramatically reduced this risk. The anterior surface of the second segment is devoid of brachial plexus elements. In the ARMS Registry, 3 of 102 patients (2.9%) had brachial plexus symptoms (all C8 tingling), all occurring after multiple days of support. The Cleveland Clinic series (Kindzelski et al.) reported zero brachial plexus injuries.
• Pneumo/hemothorax risk increases with access too proximal (first segment), which approaches the thoracic cavity. The second segment is preferred in part because it is more readily accessible for surgical bailout than the first segment.

6. Transaxillary Mechanical Circulatory Support (MCS)

• The ARMS Registry (McCabe, Kaki, Tayal et al., 2021): 102 patients across 10 US centers underwent percutaneous axillary Impella CP placement. Successful implantation in 98%. Median device dwell time was 2 days (range 0–35 days). Procedural complications included 10 bleeding events and 1 stroke. Covered stent use was 17%, decreasing with operator experience. Duration of support was independently associated with a 1.1% increased odds of vascular complication per day.
• Indications for axillary MCS over femoral include: prohibitive iliofemoral PAD, anticipated need for support >24–48 hours, desire for early patient ambulation, and cardiogenic shock patients who may need escalation of support.
• Dwell-time considerations: Devices have been maintained percutaneously for >14 days (up to 30+ days in some cases). Prolonged dwell increases thrombus risk around the access site; higher ACT targets than transfemoral are recommended. Brachial plexus symptoms may increase slightly with prolonged dwell, likely from local inflammation or nuanced bleeding.
• Device stability: Axillary Impella tends to be more stable with less need for repositioning compared with femoral. Fixation technique: Foley locks to cross-hatch the cable across the patient’s chest with the controller positioned near the umbilicus.
• Repositioning sheath: After removing the peel-away sheath (outer diameter ~17F for Impella CP), the repositioning sheath is 9F at the tip, increasing to 11–12F proximally. Leaving the peel-away sheath in place creates a 5–6F gap that promotes thrombus formation with risk of cerebral or distal embolization. Strategies to manage the downsized arteriotomy include: pulling down on the non-locking Perclose suture to snug the arteriotomy, circumferential injection of lidocaine with epinephrine to pucker the tissue, and figure-of-eight suture if needed.

7. Learning Curve and Training

• Al Adas et al. (2024): Prospective study of 146 patients undergoing percutaneous axillary access for complex endovascular aortic repair (FBEVAR). Covered stent rate was 6.9% overall, with a trend toward improvement (10% early cohort → 4% late cohort) and a significant negative correlation between cumulative complication rate and cumulative experience.
• Perclose device proficiency itself has a learning curve: data suggest ~45 cases for a vascular surgeon to achieve <5% failure rate; large-bore access increases this further. Across the US, even for large-bore femoral access without PAD, an average of 2.5 Perclose devices are used per case.
• SCAI recommends learning percutaneous axillary access through proctorship for at least the first 2–3 procedures, with operators prepared for bailout strategies.
• Training pathways include cadaveric courses for fellows transitioning to practice. No formal case-volume requirements have been established.
• The technique is transferable from basic femoral access skills and requires facility with ultrasound-guided access, micropuncture technique, and dry closure principles.

8. Axillary Artery Anatomy: Key Points

• The axillary artery is divided into three segments by the pectoralis minor muscle. Average diameter is approximately 6.2 mm (vs. ~8.5 mm for the femoral artery). Only 1–2% of patients have significant atherosclerotic disease in the axillary artery, even among those with severe iliofemoral PAD.
• First segment (medial to pectoralis minor): Larger, more superficial, but proximity to the thoracic cavity increases pneumo/hemothorax risk. Difficult for surgical bailout.
• Second segment (behind pectoralis minor): Preferred access site. Anterior surface is free of brachial plexus elements. Accessible for surgical repair. Compressible against the chest wall.
• Third segment (lateral to pectoralis minor): Smallest portion. Surrounded by brachial plexus cords and enclosed in a fascial sheath with the artery and vein. Historical access site associated with high rates of nerve injury.

9. Is Transaxillary Access a Niche Skill or an Expanding Platform?

• Currently somewhat niche, but applications are expanding beyond TAVR to include: high-risk PCI with Impella support, cardiogenic shock with prolonged MCS, complex peripheral interventions (aortoiliac CTOs), EVAR/FBEVAR, and potentially ECMO.
• The technique evolved from small-bore peripheral interventions (6–8F) for aortoiliac CTOs, then graduated to intra-aortic balloon pumps, Impella CP, and eventually large-bore TAVR sheaths.
• Operators comfortable with axillary access gain a versatile platform applicable across multiple clinical scenarios, analogous to how comfort with tibial or popliteal access expands the peripheral interventionalist’s toolkit.

References

1. ⭐ Seto AH, Estep JD, Tayal R, et al. SCAI position statement on best practices for percutaneous axillary arterial access and training. J Soc Cardiovasc Angiogr Interv. 2022;1(3):100041. doi:10.1016/j.jscai.2022.100041. Link
2. ⭐ Sherwood M, Allen KB, Dahle TG, et al. SCAI expert consensus statement on alternative access for transcatheter aortic valve replacement. J Soc Cardiovasc Angiogr Interv. 2025;4(3 Part A):102514. doi:10.1016/j.jscai.2024.102514. Link
3. ⭐ Feistritzer HJ, Dumpies O, Rosseel L, et al. Alternative access for TAVR: a state-of-the-art review and practical guide. JACC Cardiovasc Interv. 2025;18(19):2309-2325. doi:10.1016/j.jcin.2025.08.029. Link
4. ⭐ Chung CJ, Kaneko T, Tayal R, Dahle TG, McCabe JM. Percutaneous versus surgical transaxillary access for transcatheter aortic valve replacement: a propensity-matched analysis of the US experience. EuroIntervention. 2022;17(18):1514-1522. doi:10.4244/EIJ-D-21-00549. Link
5. ⭐ Southmayd G, Hoque A, Kaki A, Tayal R, Rab ST. Percutaneous large-bore axillary access is a safe alternative to surgical approach: a systematic review. Catheter Cardiovasc Interv. 2020;96(7):1481-1488. doi:10.1002/ccd.29273. Link
6. ⭐ McCabe JM, Kaki AA, Pinto DS, et al. Percutaneous axillary access for placement of microaxial ventricular support devices: the Axillary Access Registry to Monitor Safety (ARMS). Circ Cardiovasc Interv. 2021;14(1):e009351. doi:10.1161/CIRCINTERVENTIONS.120.009351. Link
7. ⭐ Palmerini T, Saia F, Kim WK, et al. Vascular access in patients with peripheral arterial disease undergoing TAVR: the Hostile Registry. JACC Cardiovasc Interv. 2023;16(4):396-411. doi:10.1016/j.jcin.2022.12.009. Link
8. ⭐ Lederman RJ, Babaliaros VC, Lisko JC, et al. Transcaval versus transaxillary TAVR in contemporary practice: a propensity-weighted analysis. JACC Cardiovasc Interv. 2022;15(9):965-975. doi:10.1016/j.jcin.2022.03.014. Link
9. Al Adas Z, Uceda D, Mazur A, et al. Safety and learning curve of percutaneous axillary artery access for complex endovascular aortic procedures. J Vasc Surg. 2024;79(3):487-496. doi:10.1016/j.jvs.2023.10.048. Link
10. Gleason TG, Schindler JT, Hagberg RC, et al. Subclavian/axillary access for self-expanding transcatheter aortic valve replacement renders equivalent outcomes as transfemoral. Ann Thorac Surg. 2018;105(2):477-483. doi:10.1016/j.athoracsur.2017.07.017. Link
11. ⭐ Dahle TG, Kaneko T, McCabe JM. Outcomes following subclavian and axillary artery access for transcatheter aortic valve replacement: Society of the Thoracic Surgeons/American College of Cardiology TVT Registry report. JACC Cardiovasc Interv. 2019;12(7):662-672. doi:10.1016/j.jcin.2019.01.227. Link
12. Kindzelski B, Mick SL, Krishnaswamy A, et al. Evolution of alternative-access transcatheter aortic valve replacement. Ann Thorac Surg. 2021;112(6):1904-1911. doi:10.1016/j.athoracsur.2020.12.043. Link
13. Ali N, Cunnington MS, Muir D, et al. Transcatheter aortic valve implantation via percutaneous axillary access — a UK registry. Catheter Cardiovasc Interv. 2026;107(4):997-1004. doi:10.1002/ccd.70435. Link
14. Kaneko T, Hirji SA, Yazdchi F, et al. Association between peripheral versus central access for alternative access transcatheter aortic valve replacement and mortality and stroke. Circ Cardiovasc Interv. 2022;15(9):e011694. doi:10.1161/CIRCINTERVENTIONS.121.011694. Link
15. Koziarz A, Kennedy SA, Awad El-Karim G, et al. Vascular closure devices for axillary artery access: a systematic review and meta-analysis. J Endovasc Ther. 2024;31(5):763-771. doi:10.1177/15266028221147451. Link
16. Fanaroff AC, Manandhar P, Holmes DR, et al. Peripheral artery disease and transcatheter aortic valve replacement outcomes: a report from the STS/ACC Transcatheter Therapy Registry. Circ Cardiovasc Interv. 2017;10(10):e005456. doi:10.1161/CIRCINTERVENTIONS.117.005456. Link
17. Kaki A, Blank N, Alraies MC, et al. Axillary artery access for mechanical circulatory support devices in patients with prohibitive peripheral arterial disease presenting with cardiogenic shock. Am J Cardiol. 2019;123(10):1715-1720. doi:10.1016/j.amjcard.2019.02.038. Link
18. Kajy M, Laktineh A, Blank N, et al. Deploying mechanical circulatory support via the axillary artery in cardiogenic shock and high-risk percutaneous coronary intervention. Am J Cardiol. 2020;128:127-133. doi:10.1016/j.amjcard.2020.04.055. Link
19. Ooms JF, Van Mieghem NM. Completely percutaneous transaxillary aortic valve implantation under local anesthesia: a minimalist alternative access approach. JACC Cardiovasc Interv. 2019;12(1):e1-e2. doi:10.1016/j.jcin.2018.10.041. Link
20. Schäfer U, Ho Y, Frerker C, et al. Direct percutaneous access technique for transaxillary transcatheter aortic valve implantation: “the Hamburg Sankt Georg approach.” JACC Cardiovasc Interv. 2012;5(5):477-486. doi:10.1016/j.jcin.2011.11.014. Link
21. Bertoglio L, Conradi L, Howard DPJ, et al. Percutaneous transaxillary access for endovascular aortic procedures in the multicenter international PAXA Registry. J Vasc Surg. 2022;75(3):868-876.e3. doi:10.1016/j.jvs.2021.08.089. Link
22. Schultz J, Duval S, Shaffer A, et al. Axillary or subclavian Impella 5.0 support in cardiogenic shock: a systematic review and meta-analysis. ASAIO J. 2022;68(2):e29-e32. doi:10.1097/MAT.0000000000001637. Link
23. Bansal A, Kalra A, Kumar A, et al. Outcomes of combined transcatheter aortic valve replacement and peripheral vascular intervention in the United States. JACC Cardiovasc Interv. 2021;14(23):2572-2580. doi:10.1016/j.jcin.2021.08.024. Link