Original Contribution

Randomized Trial of Radial Hemostasis Using Focused vs Balloon Compression Devices

Jordan G. Safirstein, MD1;  Ali Elfandi, MD1;  Nicole Reid, MD1;  Timothy W.I. Clark, MD2

Jordan G. Safirstein, MD1;  Ali Elfandi, MD1;  Nicole Reid, MD1;  Timothy W.I. Clark, MD2

Abstract: Background. Radial artery hemostasis devices differ in compression mechanisms, which may influence time to hemostasis and hand perfusion. Methods. Subjects (n = 52) undergoing transradial diagnostic coronary catheterization or percutaneous coronary intervention (PCI) were randomized 1:1 to either focused compression (VasoStat; Forge Medical) or balloon compression device (TR Band; Terumo Medical) for radial artery hemostasis. Time to complete hemostasis enabling device removal was measured in each subject. Hand perfusion was quantitated using the perfusion index (PI) with oximetry (1) before; (2) during device use; (3) during device use with ulnar artery compression; and (4) following device removal. Results. Focused compression resulted in a significantly shorter time to complete hemostasis vs balloon compression (208 min [IQR, 115-320 min] vs 242 min [IQR, 120-439 min], respectively; P=.04). This difference was greatest among the subset undergoing PCI, where the VasoStat resulted in a 43-minute reduction until complete hemostasis (P=.04). Baseline PI was similar between the focused and balloon compression groups (4.9 vs 3.9, respectively; P=.09). Focused compression resulted in a similar reduction in median PI from baseline to during device use compared with balloon compression (-27% vs -18%, respectively; P=.26). Both devices decreased PI over 50% from baseline during simultaneous ulnar artery compression (P<.01), and increased PI over 50% from baseline following device removal (P=.02). No radial artery occlusion occurred, and rates of device manipulation and access-site bleeds were low in both groups. Conclusion. Complete hemostasis was achieved earlier with the VasoStat focused compression device compared with the TR Band balloon compression device. Both devices transiently reduced hand perfusion, particularly during ulnar compression, which increased from baseline following device removal. Larger trials comparing these radial hemostasis devices and outcomes are warranted.

J INVASIVE CARDIOL 2020;32(5):169-174. Epub 2020 April 24.

Key words: hemostasis, outcomes, radial

The last decade has witnessed significant growth in the use of a radial-first strategy for coronary angiography and percutaneous coronary intervention (PCI) in the United States, the use of which currently exceeds 45%.1 Radial access has been shown to reduce bleeding complications, decrease time to ambulation, increase patient comfort, and improve overall survival in ST-segment elevation myocardial infarction (STEMI) patients following PCI compared with femoral access.2-4 Within radial access protocols, efficient and effective hemostasis strategies have been described using a variety of band-type compression devices,5-7 produced by various manufacturers, utilizing a similar mechanism of a broad-based, inflatable balloon or compressive plate to apply force over the radial artery puncture site. Ulnar artery compression may occur with such devices due to pressure applied by the edges of the balloon mechanism extending beyond the underlying radial artery to the ulnar side of the wrist, potentially reducing hand perfusion during device use. These limitations have also been suggested as one of several factors contributing to radial artery occlusion (RAO); conversely, other data suggest that simultaneous ulnar compression may augment distal perfusion through an intrinsic adaptive mechanism to produce increased radial artery flow.9,10 The VasoStat radial artery hemostasis device (Forge Medical) that achieves hemostasis using a focused compression mechanism precisely aligned over the radial arteriotomy was recently introduced in the United States and Japan. Preliminary experience has suggested that the VasoStat device may achieve hemostasis more efficiently than non-selective compression bands.11-13 We sought to compare the VasoStat with a conventional balloon compression band, the TR Band (Terumo Medical), in a randomized, prospective, pilot trial measuring time to hemostasis, clinical outcomes, and changes in hand perfusion.


Study design and population. This single-center study randomized subjects undergoing elective transradial diagnostic coronary catheterization or PCI between March and September 2018 to one of two United States Food and Drug Administration (FDA)-cleared radial artery hemostasis devices, the VasoStat focused compression device or the TR Band balloon compression device (Figure 1). A Barbeau test was conducted prior to study enrollment to confirm adequacy of the ulnar artery and palmar arch. Subjects were included if there was a Barbeau A or B waveform before the procedure and if no radial artery intervention was performed within 4 weeks of study enrollment. Subjects were excluded if allergic to medical adhesives, had an anticipated need for intraprocedural glycoprotein IIb/IIIa inhibitors, were on oral anticoagulation, had cellulitis of the overlying radial artery, or underwent placement of a radial artery sheath size that was not 6 Fr. Subjects were randomized in a 1:1 manner using permuted blocks and opaque sealed envelopes immediately prior to catheterization. A computer-generated randomization code was utilized with a random sequence of permuted block size (4, 6, or 8) to eliminate investigator anticipation of allocation. The study was approved by our facility’s institutional review board, and all subjects provided written informed consent. This study was investigator initiated, received no external funding, and was supported by the research foundation of our hospital’s cardiovascular center. 

Transradial catheterization and hemostasis device application. Diagnostic coronary catheterization or PCI was performed through a thin-walled 6 Fr Slender sheath (Terumo Medical) in all subjects. A standard radial artery cocktail was administered into the radial artery in all subjects and consisted of nitroglycerin 200 µg, verapamil 2.5 mg, and heparin 50 IU/kg, with a maximum intended dose of 5000 IU. Following each procedure, the allocated hemostasis device (VasoStat or TR Band) was applied to the puncture site following sheath removal according to randomization, and patent hemostasis technique was used for each device. To enable objective comparison of time to hemostasis, the catheterization laboratory nursing team utilized an identical monitoring frequency of puncture site assessment every 15 minutes for each device, in accordance with our center’s standing protocol for radial artery hemostasis (2 hours expected compression following diagnostic catheterization and 4 hours expected compression following PCI). However, during these regular puncture-site assessments, nurses were given clinical discretion to remove either hemostasis device earlier from these intended time points based on objective criteria showing lack of puncture-site oozing or bleeding. This involved using a 2-step ratchet-loosening technique for the VasoStat and a multistep serial balloon-deflation technique for the TR Band, as per the manufacturers’ guidelines for use of these devices. The catheterization laboratory nursing team was not apprised of the prestudy hypotheses or instructed to attempt removal of either device prior to an anticipated time point.

Covariates of interest. Age, sex, and weight were recorded for each subject, in addition to the proportion of subjects with a history of diabetes (defined as requiring insulin or oral hypoglycemics), hypertension (requiring one or more antihypertensives), hyperlipidemia (requiring statins or other therapy), peripheral arterial disease (defined as prior surgical bypass or endovascular therapy), cerebrovascular disease (prior ischemic stroke or transient ischemic attack), or end-stage renal disease (on hemodialysis or peritoneal dialysis).

Primary endpoint. The primary endpoint was time to complete hemostasis. Complete hemostasis was defined as: (1) hemostasis enabling device removal; (2) assessment of radial artery patency by plethysmography; and (3) application of a sterile dressing. Radial access site assessment was performed and recorded starting at 90-120 minutes following sheath removal and allocated device application for diagnostic-only procedures and at 180-240 minutes post PCI. The cumulative time to complete hemostasis was recorded, as well as any events of device manipulation required to achieve hemostasis, such as balloon reinflation/repositioning of the TR Band or ratcheting additional footplate pressure with the VasoStat. Evidence of bleeding or hematoma at any time during the removal of the device was measured and characterized according to the EASY (Early Discharge After Transradial Stenting of Coronary Arteries) classification proposed by Bertrand et al.14 

Secondary endpoints. Hand perfusion was measured using a previously validated metric of perfusion index (PI), which is the ratio of the pulsatile blood flow to the non-pulsatile or static blood in peripheral tissue.15-18 The PI represents a non-invasive measure of hand perfusion that can be continuously and non-invasively obtained from certain models of pulse oximeters. In this study, PI was measured using the Masimo MightySat portable pulse oximeter device (Masimo Corporation), which utilizes a 4-second sampling interval. PI was measured after 30 seconds of equilibration at 4 time points in each subject: (1) at baseline immediately prior to radial artery catheterization and sheath placement; (2) immediately after sheath removal with hemostasis device in place; (3) at 5 minutes following device application and after at least 60 seconds of sustained manual ulnar artery compression; and (4) following hemostasis device removal.

Statistical analyses. Baseline subject characteristics were compared with Mann-Whitney tests for continuous variables and Fisher’s exact test for categorical variables. Time to complete hemostasis, preprocedural/postprocedural radial artery patency assessed with Barbeau examination, and secondary device manipulations were compared using unpaired t-test and Fisher’s exact test, respectively. PI measurements were compared using Mann-Whitney test, and relative changes in PI with the Kruskal-Wallis test. All analyses were performed with STATA (Stata Software) or Prism (GraphPad Software).

Sample size. Based on our center’s prior observational data, sample size was estimated to detect a 40% difference in the PI change from baseline to during device use between each hemostasis device. Using a two-sample test of proportions, with a type I error of 5% and a power of 80%, a minimum of 40 patients (20 patients in each arm of the study) needed to be randomized (StatMate 2.0; GraphPad Software). 


Fifty-two subjects (38 men and 14 women) were randomized to radial artery hemostasis with the VasoStat focused compression (n = 26) or TR Band balloon compression (n = 26) methods. Baseline and procedural characteristics are shown in Tables 1 and 2, respectively. There were no significant differences in age, sex, weight, prevalence of comorbidities, type of procedure, median heparin dose, or median procedure duration between the two compression groups. A similar distribution of Barbeau waveforms was seen, although slightly more subjects in the VasoStat group had Barbeau A waveforms at baseline than the TR Band group (73% vs 62%, respectively; P=.55). 

Using the same monitoring protocol resulted in a significantly shorter time to complete hemostasis in the VasoStat group vs the TR Band group (34-minute reduction; 208 minutes vs 242 minutes; P=.04) (Table 2). The magnitude of this difference was greatest among the subset undergoing PCI, where the VasoStat resulted in a 43-minute reduction in time to complete hemostasis (P=.04). No RAO occurred in either group. Rates of device manipulation and EASY grade I-II hematoma were low with each device.

Transient reductions in PI were seen following device placement compared to PI at baseline (VasoStat -27%, P=.04; TR Band -18%, P=.97). Absolute and relative changes in PI are shown for each device in Figure 2. Transient ulnar compression did not increase hand perfusion in either group and conversely, significantly reduced PI during use of both devices (VasoStat -57%, P<.01; TR Band -56%, P=.04). In each group, an increase in PI from baseline following device removal was seen (VasoStat +53%, P=.03; TR Band +59%, P=.04). Median PI following device removal was 21% higher with VasoStat (P=.75). 

Four subjects in the TR Band group were observed to have changes in their Barbeau exam from baseline to discharge. At the time of discharge, two subjects in the TR Band group had worsening of baseline Barbeau waveform from A to B and 2 subjects with baseline Barbeau B were found to have Barbeau A waveforms at the time of discharge. In contrast, no subjects in the VasoStat group had worsening of baseline Barbeau waveform. 


Radial access continues to expand in the United States for coronary and peripheral procedures. According to the CathPCI database, the proportion of diagnostic coronary and/or PCIs performed from a transradial approach now exceeds 45%.1 This represents a >10-fold increase since 2010.19 Also increasing is the proportion of elective PCI performed as a same-day procedure. Radial access has greatly facilitated this transition to same-day PCI through a reduction in access-site complications, shorter times to ambulation, improved patient satisfaction, enhanced facility throughput, and increased facility reimbursement.20 Improvements in protocols and hemostasis devices for effective puncture-site management are needed to meet this growing demand for transradial PCI. We were therefore interested in comparing the VasoStat, a novel radial hemostasis device using focused compression, with a standard band-type hemostasis device using balloon compression. 

The VasoStat resulted in a significantly shorter time to complete hemostasis compared with the TR Band, with a 34-minute mean reduction in time to hemostasis enabling device removal (P=.04). This difference was greatest among the subset undergoing PCI, where the VasoStat resulted in a 43-minute reduction until complete hemostasis (P=.04). This shorter time to hemostasis with the VasoStat device was despite identical median heparin doses in both groups. We hypothesize that the convex-shaped tip of the VasoStat compression surface optimizes pressure over the anterior wall of the radial artery at the point of the arteriotomy, thereby enabling platelet plug formation more efficiently than the TR Band. The VasoStat also more closely duplicates the physics of manual compression than the TR Band; manual compression has been shown to achieve radial hemostasis significantly faster than balloon compression.21 Confirmation of this finding within a larger randomized trial would be useful, as the incorporation of a hemostasis device capable of achieving a consistently shorter time to hemostasis could represent significant cost savings and reduced nursing monitoring time in busy radial-based catheterization labs. These considerations are particularly relevant given the current trend in the United States toward same-day discharge PCI.

We did not observe RAO in either arm of this study. All radial artery patency assessments were performed within the periprocedural period and then repeated at the time of same-day discharge. It is possible that RAO in either group could have been observed with a longer period of follow-up or a larger sample size. In a retrospective series of 72 arterial access sites closed with the VasoStat device, the majority of which were radial (57%) using sheath sizes of 4-7 Fr, a single instance of RAO was seen at 30-day follow-up (1/72; 1.4%).13 In contrast, contemporary studies of the TR Band using the patent hemostasis technique have reported RAO rates of 7.5%-30.5% following PCI.6,22-24 In a recent meta-analysis of 66 studies reporting RAO following transradial intervention, Rashid et al reported a 7.7% rate of RAO within 24 hours.25 Shorter compression times were associated with significant reductions in the risk of RAO. In a randomized study by Dharma et al, longer compression times were associated with >3-fold higher risk of RAO.6

Portable plethysmography devices are a previously validated proxy of hand perfusion. Using this method to determine PI, we observed a transient reduction in hand perfusion with both the VasoStat and TR Band. The magnitude of this reduction was slightly greater with the VasoStat, which may have been due to the more focused compression force applied over the radial artery. 

Ulnar compression has been proposed as a means of augmenting radial artery blood flow during radial artery compression through physiologic compensatory modulation of radial and ulnar blood flow.9 Pancholy et al observed that the addition of ulnar compression reduced the incidence of RAO vs patients with radial compression alone.10 We are aware of at least two devices on the United States market or under development for radial artery hemostasis that utilize intermittent or continuous ulnar compression as a means of increasing radial artery flow – the Zephyr device (Advanced Vascular Devices) and the VasoBand (VasoInnovations). We hypothesized that the application of ulnar compression would produce an increase in radial artery flow and therefore increase overall hand perfusion as measured using the plethysmographic PI. However, ulnar compression during simultaneous radial artery hemostasis did not increase hand perfusion with either the VasoStat or TR Band and conversely, decreased hand perfusion from baseline by 57% and 56%, respectively. The significance of this finding is unknown, but suggests that further prospective studies may be necessary to characterize this phenomenon prior to implementing ulnar compression into routine clinical use during concurrent radial artery compression. 

Study limitations. This study has several limitations. The sample size was small, although this is typical of a pilot investigation. Our center continues to utilize relatively long compression protocols following diagnostic catheterization and PCI; these protocols were originally implemented during an era when other investigators used similar compression times. Rathore et al reported a mean compression time of 5.3 ± 2.3 hours following coronary catheterization and intervention using the TR Band,7 while Chatelain et al observed a compression time of 3.7 ± 1.1 hours following PCI using the Radistop (Abbott Vascular).26 More recent compression protocols have reported significantly shorter compression times. Using a balloon compression device similar to the TR Band (Vitatech; KDL Medical), Petroglou et al reported a compression time of 63 and 69 minutes among patients without and with RAO, respectively, although with a hematoma rate of 18%.21 

We used each device without an additional topical hemostatic agent. These agents have been shown to further reduce time to radial hemostasis.27 In clinical practice, we have utilized the central reservoir of the base of the VasoStat device as a receptacle to position and align potassium ferrate and kaolin-based hemostatic pads over the puncture site; anecdotally, we have observed this combination to result in an approximately 50% reduction in time to hemostasis. We have used similar techniques when applying the TR Band, but protocols for the combination of these approaches have not been validated or formalized; therefore, we did not incorporate hemostatic pads in this study, although it would be useful to systematically study such combinations in a future randomized trial.

Another limitation is that we observed intra- and intersubject variability in PI measurements (Figure 2), limiting the generalizability of our findings. We found both devices to be comfortable and well tolerated, although measurement of patient comfort through an objective scoring instrument was not performed.

A further limitation is that the study did not measure 30-day radial artery patency; it is possible that late instances of RAO might have occurred in either group. This limitation was inherent to the referral patterns of our tertiary referral center, whereby patients with acute coronary syndrome referred for urgent or emergent PCI are often transported from long distances. Thus, 30-day follow-up is frequently conducted with a local cardiologist and without detailed plethysmographic assessment of radial artery patency and hand perfusion.


Both focused and balloon compression achieved successful hemostasis following diagnostic cardiac catheterization or PCI. The VasoStat device achieved complete hemostasis significantly sooner than the TR Band. Through the use of a diligent patent hemostasis technique, no instances of RAO were observed in either group. Both devices produced transient reductions in hand perfusion during clinical use, which returned to or exceeded baseline levels measured prior to device application. Future studies would be helpful to elucidate which device achieves the optimal balance of efficient time to hemostasis and patient comfort.

From the 1Gagnon Cardiovascular Institute, Morristown Medical Center, Atlantic Health System, Morristown, New Jersey; and 2Penn Presbyterian Medical Center, University of Pennsylvania, Philadelphia, Pennsylvania.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Clark reports equity ownership in Forge Medical; personal fees from Teleflex, Merit Medical, Becton Dickinson, and Surmodics; patents issued in the United States, Japan, Canada, and Europe; patent pending in the United States. The remaining authors report no conflicts of interest regarding the content herein.

Manuscript submitted October 18, 2019, provisional acceptance given October 23, 2019, final version accepted November 1, 2019.

Address for correspondence: Jordan Safirstein, MD, Gagnon Cardiovascular Institute, Morristown Medical Center, 100 Madison Ave, Morristown, NJ 07960. Email: jsaf237@yahoo.com

  1. CathPCI Database. American College of Cardiology-National Cardiovascular Data Registry (NCDR), April 2017-March 2018 data. Available at: https://ncdr.com (Accessed 21 March 2020).
  2. Jolly S, Yusuf S, Cairns J, et al. Radial versus femoral access for coronary angiography and intervention in patients with acute coronary syndromes (RIVAL): a randomised, parallel group, multicentre trial. Lancet. 2011;377:1409-1420.
  3. Romagnoli E, Biondi-Zoccai G, Sciahbasi A, et al. Radial versus femoral randomized investigation in ST-segment elevation acute coronary syndrome. J Am Coll Cardiol. 2012;60:2481-2489.
  4. Ferrante G, Rao S, Juni P, et al. Radial versus femoral access for coronary interventions across the entire spectrum of patients with coronary artery disease: a meta-analysis of randomized trials. JACC Cardiovasc Interv. 2016;9:1419-1434.
  5. Pancholy SB, Coppola J, Patel T, Roke-Thomas M. Prevention of radial artery occlusion-patent hemostasis evaluation trial (PROPHET study): a randomized comparison of traditional versus patency documented hemostasis after transradial catheterization. Catheter Cardiovasc Interv. 2008;72:335-340.
  6. Dharma S, Kedev S, Patel T, Kiemeneij F, Gilchrist IC. A novel approach to reduce radial artery occlusion after transradial catheterization; post procedure/prehemostasis intra-arterial nitroglycerin. Catheter Cardiovasc Interv. 2015;85:818-825.
  7. Rathore S, Stables RH, Pauriah M, et al. A randomized comparison of TR band and Radistop hemostatic compression devices after transradial coronary intervention. Catheter Cardiovasc Interv. 2010;76:660-667.
  8. United States Food and Drug Administration. Manufacturer and user facility device experience (MAUDE) database. Available at: https://www.accessdata.fda.gov (Accessed 21 March 2020). 
  9. Pancholy S, Heck LA, Patel T. Forearm arterial anatomy and flow characteristics: a prospective observational study. J Invasive Cardiol. 2015;27:218-221.
  10. Pancholy S, Bernat I, Bertrand OF, Patel TM. Prevention of radial artery occlusion after transradial catheterization. JACC Cardiovasc Interv. 2016;9:1992-1999.
  11. Toyoda M, Ogasawara Y, Tuya A, et al. Evaluation of hemostasis device for transradial intervention. Japanese Association of Cardiovascular Intervention and Therapeutics Annual Meeting, Kyoto, Japan, July 2017 (Abstr).
  12. Hiramatsu Y. Evaluation of a rapid hemostasis protocol with the VasoStat hemostasis device. Japanese Association of Cardiovascular Intervention and Therapeutics Annual Meeting, Kyoto, Japan, July 2017 (Abstr).
  13. Clark BJ, Redmond JW, Brandis ARB, Clark TWI. Use of a novel hemostasis device after peripheral arterial interventions. J Vasc Interv Radiol. 2017;28:S131-S132.
  14. Bertrand O, De Larochellière R, Rodés-Cabau J, et al. A randomized study comparing same-day home discharge and abciximab bolus only to overnight hospitalization and abciximab bolus and infusion after transradial coronary stent implantation. Circulation. 2006;114:2636-2643.
  15. Hager H, Reddy D, Kurz A. Perfusion index — a valuable tool to assess changes in peripheral perfusion caused by sevoflurane? Anesthesiology. 2003;99:A553.
  16. Genzel-Boroviczeny O, Strotgen J, Harris A, Messmer K, Christ F. Orthogonal polarization spectral imaging (OPS): a novel method to measure the microcirculation in term and preterm infants transcutaneously. Pediatric Research. 2002;51:386-391.
  17. De Felice C, Latini G, Vacca P, Kopotic RJ. The pulse oximeter perfusion index as a predictor for high illness severity in neonates. Eur J Pediatric Medicine. 2002;161:561-562.
  18. Zaramella P, Freato F, Quaresima V, et al. Foot pulse oximeter perfusion index correlates with calf muscle perfusion measured by near-infrared spectroscopy in healthy neonates. J Perinatology. 2005;25:417-422.
  19. Feldman D, Swaminathan R, Kaltenbach L, et al. Adoption of radial access and comparison of outcomes to femoral access in percutaneous coronary intervention: an updated report from the National Cardiovascular Data Registry (2007-2012). Circulation. 2013;127:2295-2306.
  20. Amin A, Pinto D, House J, et al. Association of same-day discharge after elective percutaneous coronary intervention in the United States with costs and outcomes. JAMA Cardiol. 2018;3:1041-1049.
  21. Petroglou D, Didagelos M, Chalikias G, et al. Manual versus mechanical compression of the radial artery after transradial coronary angiography. JACC Cardiovasc Interv. 2018;11:1050-1058.
  22. Zankl A, Andrassy M, Volz C, et al. Radial artery thrombosis following transradial coronary angiography: incidence and rationale for treatment of symptomatic patients with low-molecular-weight heparins. Clin Res Cardiol. 2010;99:841-847.
  23. Uhlemann M, Möbius-Winkler S, Mende M, et al. The Leipzig prospective vascular ultrasound registry in radial artery catheterization. JACC Cardiovasc Interv. 2012;5:36-43.
  24. Garg N, Madan B, Khanna R, et al. Incidence and predictors of radial artery occlusion after transradial coronary angioplasty: Doppler-guided follow-up study. J Invasive Cardiol. 2015;27:106-112.
  25. Rashid M, Kwok C, Pancholy S, et al. Radial artery occlusion after transradial interventions: a systematic review and meta-analysis. J Am Heart Assoc. 2016;5:e002686.
  26. Chatelain P, Arceo A, Rombaut E, Verin V, Urban P. New devices for compression of the radial artery after diagnostic and interventional cardiac procedures. Cathet Cardiovasc Diagn. 1997;40:297-300.
  27. Seto A, Rollefson W, Patel MP, et al. Radial haemostasis is facilitated with a potassium ferrate haemostatic patch: the Statseal with TR Band assessment trial (STAT). EuroIntervention. 2018;14:e1236-e1242.