Historically, varying definitions of major bleeding have been studied across different PCI registries and clinical trials, and it has been shown to be a powerful predictor of morbidity and mortality (9–13). A summary of the most commonly used bleeding nomenclatures is highlighted in Table 1. While bleeding following cardiac catheterization may occur from a variety of sources, more than 50% of cases are due to access site complications (14, 15). An analysis of 15,968 patients from the GLOBAL LEADERS study, a contemporary randomized clinical trial comparing 1-month vs. 12-month dual antiplatelet therapy following PCI in an all-comer patient population, reported a 6.6% risk of Bleeding Academic Research Consortium (BARC) 2, 3, or 5 bleeding (16). Overall, 11 percent of patients with a bleeding event died during the two-year follow-up, and the presence of even a minor periprocedural bleed imparted a 1.8-fold increase-risk for mortality beyond 1 year (16). The clinical and economic impacts of periprocedural bleeding are significant, with up to 14% of patients undergoing a blood transfusion and each complication contributing to nearly $12,000 in increased costs (15–17). Notwithstanding the stabilizing effects of increased circulatory volume and oxygen carrying capacity, the practice of blood transfusion is associated with a deleterious impact on clinical outcomes following PCI, with 3-fold increased risk of mortality and major adverse cardiac events (18). This effect is likely multifactorial, due to a combination of increased platelet reactivity, upregulation of plasminogen activator inhibitor proteins, reductions in 2, 3-diphosphoglyceric acid and nitric oxide levels in the stored red blood cells (19–22).

The prognostic implications of major bleeding complications are only further amplified in patients undergoing large bore access for MCS devices or structural heart interventions, often with delivery catheters that are 14 Fr or greater in diameter (23–25). In the case of the former, they are frequently inserted under emergency circumstances when patients are experiencing circulatory collapse (8). These findings were noted in recent observational data from the Cath-PCI and Chest Pain-MI registries which showed that among 1,680 propensity matched pair patients with acute myocardial infarction complicated by CS undergoing PCI, those supported with axial-flow percutaneous ventricular assist devices (pVAD) had double the risk of bleeding with more than 10-fold increased risk of death compared to patients supported with smaller platform intra-aortic balloon pumps (23). Frequently performed under more elective circumstances, patients undergoing structural heart interventions are similarly at risk for access site complications. While there has a notable decline from the nearly 15% incidence rates of periprocedural bleeding and vascular complications seen in the early days of TAVR due to smaller 14 Fr sheaths delivery systems, the frequency of these adverse events and variations in clinical expertise around recognition and management remain significant (26, 27). A contemporary analysis of 34,893 patients undergoing TAVR from the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy (TVT) Registry from 2011 to 2016 observed a 7.6% incidence of in-hospital bleeding events (28). Significant inter-hospital variations were noted, with complication rates ranging from 0% to 46% among the 345 TVT sites (28). A bleeding complication was associated with significant increased risk for death and hospital readmissions at 1 year (28).

Since its first description by Lucien Campeau in 1989, the adoption of transradial access (TRA) has steadily increased worldwide (29–31). It is associated with reductions in bleeding and vascular complications as well as major adverse cardiac events compared to transfemoral access (TFA) across the spectrum of coronary artery disease (32). It is also associated with improved quality-of-life outcomes, with reductions in bed rest time and bodily pains (33, 34). There are also potential economic benefits to TRA, with a significant reduction in healthcare costs related to not only fewer access site complications, but also shorter hospital lengths of stay, with nearly 20% increased likelihood for same-day discharge following elective PCI (35–37). A contemporary analysis of 279,987 PCI patients observed a nearly $3,700 adjusted savings in hospital costs in patients undergoing TRA for PCI who were discharged home the same day (36). With advances in radial sheaths and associated catheter technologies, TRA is also feasible in high-risk patients with complex coronary anatomy or hemodynamic compromise, where larger sheath sizes may be needed to facilitate intervention. In these circumstances, TRA is feasible without any appreciable increased risk for bleeding/vascular complications, contrast or radiation exposure (38). Given these considerations, TRA is recommended as the default access site for patients undergoing diagnostic coronary angiography and PCI (39–41).

Initial observational studies with TRA demonstrated lower rates of major and minor bleeding compared to TFA, particularly in high-risk subgroups (42, 43). A retrospective cohort study of 2,820,874 PCI procedures from the National Cardiovascular Data Registry from 2007 to 2012 demonstrated that while TRA accounted for only 1 in 6 PCI's, it was associated with a significantly lower adjusted risk of bleeding (aOR 0.51; 95% CI: 0.49–0.54; p < 0.001) and vascular complications (aOR 0.39; 95% CI: 0.31–0.50; p < 0.001) compared to TFA, with the greatest benefit seen in women, patients ≥75 years of age and those with ACS (42). Similar finding were noted in the UK where TRA was adopted earlier, with marked reductions in major adverse cardiac events in patients with both stable ischemic heart disease and acute coronary syndrome (ACS) (35, 44–46).

The Radial vs. Femoral Access for Coronary Intervention (RIVAL) trial initially showed the greatest bleeding reductions among centers with the highest TRA utilization rates, suggesting that there may be volume-outcome relationship with utilizing the radial artery (44). However, subsequent studies including Radial vs. Femoral Randomized Investigation in ST-Elevation Acute Coronary Syndrome (RIFLE-STEACS) and Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systematic Implementation of angioX (MATRIX), further confirmed these findings across the spectrum of TRA-expertise with reductions in composite endpoints encapsulating outcomes such as death, MI, stroke, recurrent MI and target lesion revascularization (35, 46). Subsequent investigations, including a meta-analysis of 24 studies and a post-hoc examination of a high volume North American quaternary care center, have subsequently confirmed these findings with reductions in major adverse cardiac events compared to TFA across the severity spectrum of CAD, including cardiogenic shock (32, 47). Interestingly, the most recently published study in this field, The Safety and Efficacy of Femoral Access Versus Radial for Primary Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction (SAFARI-STEM) trial, was terminated early due to futility as it failed to demonstrate the superiority of TRA in STEMI with regards to 30-day all-cause mortality, non-surgical TIMI major bleeding, or death/re-infarction/stroke compared to TFA in patients with STEMI (48). While this study has been scrutinized for its limited statistical power and for enrolling patients with lower acuity of illness and bleeding risk than previous trials, its findings do highlight the need for the development of institutional competency pathways in vascular access so that operators may remain facile with both access techniques in contemporary clinical practice. A summary of the pertinent RCT's evaluating TRA is highlighted in Table 2.

Access site complications associated with TRA occur infrequently, between 0.2%–1.0% of cases (32). While rare, they can be associated with significant morbidity. Thus it is important to recognize and manage these sequelae in timely fashion. Vascular complications which may be seen following TRA include radial artery spasm, perforation, occlusion due to intimal medical hyperplasia, arteriovenous fistulae and forearm hematomas with compartment syndrome (49). Like most cardiac procedures, there is a learning curve with accessing the radial artery safely and effectively. It is recommended that operators learning TRA perform at least 50 cases initially followed by a minimum of 80 procedures annually to achieve and maintain proficiency, respectively (50). It has also been demonstrated that operators facile with TRA are able to perform both diagnostic cardiac catheterizations and coronary interventions with similar efficacy and safety vs. femoral access, as demonstrated by comparable radiation dosages and total fluoroscopy/procedural times in high-radial volume centers (48, 51).

A “radial-first” approach is strongly encouraged for all-comers undergoing coronary angiography or PCI (39). The radial artery however is small, typically measuring 2.2 mm–2.6 mm in diameter, and inability to successfully cannulate the vessel is a major contributor to nearly 60% of cases in which there is TRA failure (52). The radial approach can also be challenging in patients with systemic vasculitides, such as Raynaud's disease, as well as in patients with chronic kidney disease due to calcified vessels, brachiocephalic tortuosity, and in those with prior ipsilateral mastectomies with lymph node dissection (39). In the case of the latter, caution against TRA has been borne out of concern for potential risk of access site infection and lymphedema, although this has not been seen in observational studies (53). During TRA, the radial artery is subject to trauma resulting from intimal tears, medial dissection, long-term intimal medial thickness, and impaired flow-mediated vasodilation (54–56). These acute and chronic changes in turn may compromise its utility to serve as a suitable conduit for future coronary artery bypass grafting (CABG) and non-cardiac surgeries, such as arteriovenous fistula formation (56). While not an absolute contraindication to TRA, it is advised to avoid using the ipsilateral radial artery for CABG for at least 3 months given observational data demonstrating reduced radial artery bypass graft patency (3). Historically, confirmation of dual arterial supply to the palmar arch had been required prior to TRA, by examining pulse oximetric waveform patterns following manual occlusion of the ipsilateral radial artery. Commonly referred to as the Barbeau or Allen exams, these pre-procedural tests were once widely performed to predict the risk of hand ischemia. However, given a recent study failing to demonstrate significant differences in thumb capillary lactate, hand grip strength or discomfort between patients with normal and abnormal Barbeau exams, routine pre-procedural assessment of collateral hand circulation is no longer recommended and should not preclude TRA (3, 57). While most interventionalists prefer right TRA primarily because of ergonomic purposes, consideration may be given to left TRA in certain cases. These include patients with brachiocephalic tortuosity and those who have undergone CABG with left internal mammary arteries, although right TRA may still be feasible in these circumstances (58–61). The use of two-dimensional ultrasound may facilitate more timely radial arterial puncture by allowing for direct visual inspection of vessel size, potential anatomic anomalies, needle tip puncture, wire passage and sheath insertion. Several studies have published the benefits associated with ultrasound-guided TRA, including a meta-analysis of 12 studies (n = 1,992) and the Radial Artery Access with Ultrasound Trial (RAUST), a multi-center RCT of 698 patients undergoing TRA who were randomized to manual palpation or ultrasound guidance (62, 63). Both studies showed enhanced efficiency and success with TRA when US was utilized, with the former also reporting reductions in site hematomas, findings which result in reductions radial artery occlusion (RAO) up to 30 days post-procedure (62–64). TRA may be obtained either by way of single- or double-wall puncture, with the latter technique associated with higher rates of successful puncture on the first attempt (65). In cases in which TRA is not successful, the ipsilateral brachial or ulnar arteries may be considered as alternative conduits. Limited studies have demonstrated comparable safety and efficacy between the radial and ulnar access sites, although the ulnar approach was associated with increased access site cross-over (66, 67). While not observed in clinical studies, caution is advised with ulnar access in patients with occluded ipsilateral radial arteries given the risk for hand ischemia with ulnar nerve injury (68).

During TRA, concerted efforts should also be made to undertake measures to prevent radial artery occlusion (RAO), a multifactorial phenomenon stemming from vascular injury and inflammatory changes of arterial wall during sheath insertion. Procedural factors associated with RAO include insufficient anticoagulation, sheath-to-arterial diameter ratio >1, multiple puncture attempts, vasospasm and prolonged occlusive hemostasis (64, 69–74). Pharmacologic measures to achieve this goal include adequate administration of moderate sedation and local analgesia, anti-spasmolytic therapy with intra-arterial nitroglycerine (100–200 μg) and verapamil (5 mg), as well as systemic anticoagulation with intra-arterial or intravenous heparin (at least 5,000 U or 50 U/kg bolus) following sheath insertion (69, 70, 75). Iterative advances in TRA technology with reductions in sheath size and hydrophilic coating have also advanced the field, allowing operators to perform complex PCI via TRA with relative impunity. An example of this advancement is the 6 Fr Glidesheath Slender (Terumo, Somerset, NJ), a novel thin-walled sheath design with 5 Fr (2.46 mm) outer diameter while maintaining 6 Fr inner architecture. This technology was compared in a randomized, multi-center non-inferiority trial with standard 5 Fr technology, and no differences were noted with regards to RAO, vasospasm, access-site vascular complications or local bleeding (71). Cordis (Rainsheath) and Merit Medical (Prelude Ideal) similarly have thin-walled sheath platforms which can facilitate complex PCI using 7 Fr guide catheters. An alternative conduit for TRA coronary angiography and PCI are sheathless systems, which are usually 1–2 Fr smaller than standard sheaths and obviate the need for additional mechanical stretch of the radial artery (76). Two commonly used sheathless platforms are the Eucath (Asahi, Irvine, CA) and the Railway (Cordis, Hialeah, Fl) systems. They are introduced using a dilator and without the need for a sheath, and while 5 Fr, 6 Fr, or 7 Fr catheters can be used with these technologies, catheter backup and manipulation may not be as consistent as with traditional sheathed systems. Sheathless guide catheters have been evaluated in non-randomized cohort studies with successful outcomes in patients with calcified and bifurcation lesions (77, 78). While there have not been any randomized clinical trials studying thin-wall sheaths and sheathless platforms for PCI in head-to-head fashion, a recent propensity-matched analysis of 728 patients with acute coronary syndrome, those undergoing transradial PCI using a 7 Fr Glidesheath Slender had lower rates of RAO (OR = 0.32, 95% CI: 0.11–0.93; p = 0.036) (79) Further research is needed to better understand the optimal transradial platform for performing safe and effective higher risk PCI in patients with complex CAD. A summary of currently available transradial sheaths and sheathless systems is described in Table 3 (80).

Upon completion of the cardiac catheterization, steps should be undertaken to ensure safe and effective hemostasis. A number of radial occlusion devices are currently available for commercial use. To date, a strategy of patent hemostasis has been shown to be most effective in reducing the rates of RAO, with the Prevention of Radial Artery Occlusion—Patent Hemostasis Evaluation (PROPHET) study demonstrating reductions in early (<24 h) and late (30 days) incidence of RAO of 59% and 75%, respectively, compared to a strategy of conventional pressure application (73). Shorter durations of hemostatic compression have been associated with reductions in radial artery compromise, with many centers employing protocols which advocate for patent hemostasis times of 2 and 4 h following diagnostic angiography and PCI, respectively (69). Prophylactic ipsilateral ulnar artery compression following completion of transradial cardiac catheterization has also been shown to be efficacious in not only facilitating safe and patent hemostasis of the RA, but also in reducing the risk of RAO. The PROPHET-II (PROPhylactic Hyperperfusion Evaluation Trial), a multicenter randomized clinical trial of 3,000 patients undergoing TRA for cardiac catheterization demonstrated that a strategy of occlusive compression of the ipsilateral ulnar artery at the Guyon's canal at the time of radial band application followed by removal of the radial sheath and patent hemostasis was associated with nearly 3-fold reduction in RAO up to 30-days post-procedure compared to patent hemostasis alone (81). It is recommended that TRA centers develop post-procedural care pathways and quality assurance mechanisms to ensure that multi-modality assessments are employed to ensure timely hemostasis and early ambulation following transradial coronary angiography or PCI (39).

More recently, distal transradial access (dTRA) in the “anatomic snuffbox” a triangular depression on the dorsum of the hand that is bordered by the extensor pollicis brevis and abductor pollicis longus tendons laterally and by the extensor pollicis longus tendon medially, has been proposed as an alternative cannulation site to traditional TRA in the wrist (82). In addition to ergonomic benefits and shorter hemostasis times due to the superficial location of the distal RA with a boney basement in the snuffbox, dTRA may also potentially impart greater reductions in RAO compared to traditional TRA (83, 84). The putative mechanism for this hypothesis is the more distal location of the puncture site, which in turn may facilitate greater preservation of flow in the radial artery proximally, due to the rich cascade of adjacent collateral networks from the deep palmar arch. The safety and feasibility of dTRA for coronary angiography and PCI has been demonstrated, with clinical trial data suggesting greater reductions in RAO, as determined by doppler ultrasound, compared to traditional TRA (84, 85). Little is known, however, regarding the pathobiology of radial artery injury and remodeling following dTRA. The PRESERVE Radial study (A PRospEctive Randomized Clinical Study Comparing Radial ArtERy Intimal Hyperplasia Following Distal Vs. ForEarm TransRADIAL Arterial Access for Coronary Angiography) (NCT04801901) will be the first clinical trial to compare intimal medial hyperplasia and other markers of vessel healing following dTRA and traditional TRA using ultrahigh resolution ultrasound. Given the more superficial location and potential tortuosity of the radial artery in the snuffbox, however, patients undergoing dTRA may experience greater number of puncture attempts, time-to-sheath insertion and access-site crossover (84, 86).

Despite a significant shift towards TRA for coronary angiography and PCI, the femoral artery remains a necessary conduit for numerous procedures in contemporary clinical practice, such as the insertion of percutaneous MCS devices and TAVR. It is still also required in non-large bore coronary angiogram/PCI cases (<8 Fr) where TRA or ulnar access are not feasible. Contemporary TFA should ideally employ four multimodality techniques: 1. Fluoroscopy; 2. Doppler ultrasound; 3. Micropuncture needles; and 4. Iliofemoral angiography (87). Familiarity with femoral artery anatomy is key to safe and efficient vascular access and closure. The Common Femoral Artery (CFA) is a continuation of the External Iliac Artery and lies below the inferior epigastric artery, the anatomic location of the inguinal ligament, where the vessel dives posteriorly into the retroperitoneal space. Distally, the CFA bifurcates into the Superficial Femoral Artery (SFA) and Profunda Femoris Artery (PFA). The angiographic anatomy of the femoral arteries are shown in Figure 2. The following steps are recommended for optimal TFA (87): 1.

The inferomedial edge of the femoral head should be identified under fluoroscopy and its position should be noted either by way of a hemostat or marker.

Routine utilization of ultrasound should be the standard of care for all TFA cases for optimal access and preventing the risk for vascular complications (Figure 3) (87). The merits of ultrasound guidance for femoral access have been studied extensively, including a meta-analysis of 1,422 patients demonstrating nearly 50% reduction in all complications, including bleeding and accidental puncture, as well as 42% improvement in likelihood of successful arterial access on the first attempt (90–93). The Femoral Arterial Access with Ultrasound Trial (FAUST) demonstrated that the use of ultrasound was associated with 80% increased likelihood of first-pass success, 85% reduced risk of accidental venipuncture and nearly 60% reduction vascular complications compared to fluoroscopic guidance (90). The greatest benefit with successful vessel cannulation was noted with common femoral arterial bifurcations above the femoral head, an inherently high risk cohort of patients (90). Interestingly, the routine Ultrasound Guidance for Vascular Access for Cardiac Procedures (UNIVERSAL) Trial, a multi-center prospective study 621 patients undergoing TFA for coronary angiography or PCI, failed to show a decrement in Bleeding Academic Research Consortium 2, 3, or 5 major bleeding or vascular complications with ultrasound-guided access compared with manual palpation, although the former was associated with reduced number of access attempts and accidental venipunctures (94). While the study has been critiqued for not mandating the use of micro puncture catheters and for including BARC 2 minor bleeds which may be unrelated to the procedure, the findings do highlight the need for further research in the form of large multicenter registries and clinical trials evaluating the potential benefits of skilled ultrasound utilization to reduce the risk of adverse periprocedural sequelae during TFA (95).

Historically, manual compression has been the standard of care for achieving hemostasis following femoral arterial sheath removal, usually once activated clotting time (ACT) has been less than160–180 s (96). Given the labor intensive nature of digital compression by catheterization laboratory staff members, a number of mechanical compression devices, such as the Femostop (Radi Medical System) and CompressAR C-clamp (Advanced Vascular Dynamics) were subsequently developed, with some studies suggesting that they may be associated with reduced vascular complications compared with manual hold (97–99). Despite the benefits of allowing staff members to be relieved from the demands of bedside manual compression, these devices do need careful supervision to ensure that they do not migrate and that they are not applied at pressures which could compromise limb flow and result in arterial and/or venous thrombosis.

In response to the logistical challenges associated with manual pressure and passive closure platforms, a variety of vascular devices (VCD) have been developed since the mid 1990s which can be deployed at the conclusion of cardiac catheterization, allowing for potentially faster hemostasis, shorter duration of bed rest and reductions in patient discomfort (96). They are used in up to 75% of TFA cases in contemporary clinical practice (100). VCD's have historically been classified into 4 categories: plugs, sutures, glues or topical patches. Despite their potential to improve patient satisfaction and clinical throughput, the evidence supporting their use has been limited to observational studies and modest sized clinical trials (100). These studies have demonstrated the safety and feasibility of VCD's, but they have not provided definitive evidence around efficacy or reductions in bleeding complications compared to manual compression (100–105). As such, caution is advised with the routine deployment of these devices following TFA. Instead, societal guidelines advocate for a patent-centered approach that takes into consideration clinical factors such as body habitus, arteriotomy location and vessel anatomy (size, calcification tortuosity) (101). It is advised that all patients undergoing cardiac procedures via TFA undergo femoral angiography prior to closure to determine whether the arteriotomy site and vessel anatomy are suitable for the deployment of these devices. Potential complications associated with these devices include acute limb ischemia, bleeding, infection, distal embolization, pseudoaneurysm and arteriovenous fistula formation (106, 107). It is recommended that interventionalists have familiarity with all device and that they able to address any potential device-related complications with facile expertise (108). Table 4 provides a summary of the some of the currently Food and Drug Administration approved VCD's employed in clinical practice in the United States.

The Angio-Seal system (Terumo, Somerset, NJ) is one of the most commonly used platforms in the United States, consisting of a co-polymer which is deployed intravascularly and attached by an absorbable Dexon traction suture to an extravascular collagen plug (96). It was first studied against manual compression in a multi-center RCT of 435 patients undergoing cardiac catheterization and was noted to have 85% reduction in time to hemostasis and lower rates of bleeding and hematomas (109). These results were further observed in a subsequent clinical trial of 612 patients undergoing PCI who were randomized to Angio-Seal or manual compression (110). These patients had select high risk features for vascular complications (age >70, previous puncture at the same site, hypertension, treatment with ticlopidine at least 2 days prior, use of abxicimab, 8 Fr access, prolonged heparin treatment after the angioplasty, and use of fibrinolytics) (110). Angio-Seal was associated with significant reductions in time to hemostasis, total bedrest time, and bleeding (110). Available in 6 and 8 Fr platforms, Angio-Seal is rapidly deployable with hemostasis success rates of up to 97% (107).

The ProGlide Perclose device (Abbott Vascular, Abbott Park, IL) is a suture-mediated device that is advanced over an 0.035″ J wire through the arteriotomy after the femoral sheath is removed. Once the return of pulsatile blood is noted from the side arm, the device lever is pulled and two simultaneous needles are deployed through the anterior wall of the femoral artery utilizing the non-biodegradable polypropylene microfilament with preformed knot that is tightened to form the suture loop. The suture is then retracted to the anterior wall of the arteriotomy site and deployed to achieve hemostasis (96) (Figure 4). The Perclose platform is unique among VCDs as it maintains access to the vessel by way of the 0.035 inch guidewire after the needles and suture have been deployed. Therefore if the needles do not capture the sutures and adequate hemostasis is not achieved, the guidewire may be re-introduced into the arteriotomy and ultimately removed following confirmation of satisfactory hemostasis. Similar to the Angio-Seal device, Perclose has been associated with reduced time to hemostasis and ambulation with no significant differences in bleeding complications compared to manual hemostasis (111, 112). In experienced hands, it can also be associated with significant costs savings as it may obviate the need for further manpower and work personnel typically associated with manual compression (113).

The MANTA™ vascular closure received pre-market investigational device exemption approval by the Food and Drug Administration in 2019 following multi-center observational data demonstrating safety and feasibility in 263 patients undergoing TAVR and percutaneous endovascular thoracic and abdominal aortic aneurysm repair (114). With an effective sheath outer diameter of 22 Fr or 7.3 mm, rapid closure was able to be achieved, with median time to hemostasis of 24 s and only 4.2% rate of Valve Academic Research Consortium-2 major vascular complications (114). A collagen-based platform, it is currently available in 14 Fr and 18 Fr configurations, and it is 0.035″ guidewire compatible, consisting of a poly-lactic-co-glycolic snap attached to a bovine collagen plug which is tampered down, sandwiching the arteriotomy while a toggle is deployed intravascularly. The toggle and collagen plug usually are fully absorbed within 6 months and the vessel may be re-accessed 2.5 cm cranial or caudal to the MANTA device (96). The safety and efficacy of MANTA was recently compared with Proglide in the Randomized Comparison of Catheter-based Strategies for Interventional Access Site Closure during Transfemoral Transcatheter Aortic Valve Implantation (CHOICE-CLOSURE) study, a multi-center RCT of 516 patients undergoing TAVR (115). The authors reported significantly lower times to hemostasis with MANTA [80 (32–180) vs. 240 (174–316) seconds; p < 0.001) but at the cost of increased rates of access-site vascular complications [relative risk, 1.61 (95% CI: 1.07–2.44), p = 0.029], in particular pseudoaneurysms and hematomas (115). No differences were noted, however, with respect to access site bleeding or device failure. Historically, vascular closure following TAVR and other large bore access procedures has been performed by tightening the knots of 1 or 2 Perclose devices which were partially deployed at the time of initial access (“pre-closure”) (116).Further research is needed in the form of large multi-center registries and nested clinical trials using standardized best-practices to identify closure strategies in patients undergoing large bore access that are the most safe, effective and cost-sensitive.

The employment of safe and effective femoral arterial access is of paramount importance in patients requiring large bore sheaths (>8 Fr) for structural heart interventions, endovascular aneurysm repairs and percutaneous MCS placement. Despite advances in device-based therapies to treat these conditions using minimally invasive techniques, there remain significant variations in the technical expertise of large bore access within and among institutions (6, 8). A contemporary analysis of 17,672 patients undergoing large bore access for TAVR, EVAR and percutaneous MCS observed an 18% rate of bleeding complications, which in turn was associated with nearly 3-fold increased risk for in-hospital mortality, 2-fold increase in hospital-length-of-stay and marked increases in total healthcare costs (25). In cases requiring MCS implantation under emergency circumstances, the rates of bleeding and vascular complications can be as high as 40%, with greater than 4-fold increased risk for acute ischemia if advanced platforms such as percutaneous ventricular assist devices or VA-ECMO are utilized (117, 118). A summary of currently available MCS and structural heart platforms with their respective sheath sizes is described in Table 5. Given these considerations, societal recommendations and position statements have been developed around best practices for proper large bore femoral arterial access and closure (8, 119): 1.

Similar to standard TFA, multi-modality imaging techniques should be employed to visualize the common femoral artery, including bifurcation, calcification and dimensions, with a minimal diameter of 6 mm typically needed for sheath sizes of up to 18 Fr. In elective circumstances such as TAVR, pre-procedural computed tomography may also be performed to assess iliofemoral anatomy, in addition to other anatomic considerations, such as annular dimensions, valvular calcification and coronary artery height (120).