Radial access for chronic total occlusion percutaneous coronary intervention: insights from the PROGRESS‐CTO registry

Selected in Catheterization and Cardiovascular Interventions by A. Cader , S. R. Khan

This analysis of the large multinational Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS‐CTO) registry1 examined prevalence, temporal trends, and clinical outcomes of radial versus femoral access in CTO PCI.

Reviewers

Aaysha Cader

@aayshacader

Cardiology SpR

Kettering General Hospital NHS Foundation Trust - Kettering, United Kingdom

Saidur Rahman Khan

@drsaidurrahman2

Interventional cardiologist / Cardiologist

Ibrahim cardiac hospital and research institute - Dhaka, Bangladesh

Our Comment

Why this study – the rationale/objective? 

Complex percutaneous coronary interventions (PCI), including chronic total occlusion (CTO) PCI, are increasingly being undertaken by a transradial approach (TRA), with encouraging outcomes.

This analysis of the large multinational Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS‐CTO) registry¹ examined prevalence, temporal trends, and clinical outcomes of radial versus femoral access in CTO PCI².

How was it executed? - the methodology

Design:

This was an observational analysis of the PROGRESS CTO registry, comprising of patient-level data from 2012 through 2022, of experienced CTO PCI centres from 7 countries.

Patients were divided into three groups by access site, and variables were compared by appropriate statistical tests:

1. Radial only: includes single and bi-radial access, with absence of any transfemoral access (TFA)
2. Radial / femoral: right or left TFA, regardless of TRA
3. Femoral only: includes single and bi-femoral access, i.e. only TFA without TRA

Outcomes:

Technical success, in-hospital mortality, major adverse cardiovascular events (MACE), and vascular access site complications were analysed as outcomes.

What is the main result?

A total of 10,954 patients that underwent CTO PCI were analysed.

The distribution of access site was as follows:

• Radial only: ~ 24 %; among whom 11.78 % had single radial access, and 11.76 % had biradial access
• Radial / femoral: 28.77 %
• Femoral only: ~ 48 %, among whom 14.87 % had single femoral access and 32.83 % had bifemoral access

Demographic characteristics:

Compared with femoral access, patients in the radial-access-only group were younger (63 ± 10 vs. 65 ± 10, years, p < 0.001), more likely to be male, and had significantly lower prevalence of comorbidities including diabetes mellitus, prior PCI (57 % vs. 64 %, p < 0.001) and prior coronary artery bypass graft surgery (17 % vs. 33 %, p < 0.001).

Angiographic characteristics:

Those who underwent radial-only access also had less angiographic complexity of CTO lesions. These included lower incidence of proximal cap ambiguity, moderate / severe proximal tortuosity, and moderate‐severe calcification, with shorter CTO length, and significantly lower J‐CTO, and PROGRESS‐CTO scores, as compared with the femoral group. There were more balloon undilatable or uncrossable lesions in the femoral group².

Ad hoc PCI was undertaken more frequently in the radial-only access group (12.2 % vs. 8 %, p < 0.001), although consumables were significantly higher in the femoral group, as were procedure time, contrast volume, and fluoroscopy time.

CTO crossing technique:

Antegrade wiring (94 % vs. 85 %, p < 0.001) was more frequently adopted in the radial-only group, while retrograde crossing was used more often in the femoral group (18 % vs. 36 %, p < 0.001).

In terms of temporal trends, a distinct reduction of bifemoral access use in CTO PCI was noted over time (from 80 % in 2012 to 31 % in 2021), replaced by increasing use of radial access and combined femoral / radial access.

Procedural & in-hospital outcomes:

In the radial-only group, greater technical success, and significantly fewer in‐hospital complications were seen, including lesser all‐cause mortality, MACE, coronary perforation, and vascular access complications.

However, after adjusting for potential confounders, while radial-only access remained associated with lower risk of access site complications, as compared with the femoral access group (odds ratio [OR]: 0.45, 95 % confidence interval [CI]: 0.22–0.91), similar technical success (OR: 0.87, 95 % CI: 0.74–1.04) and MACE (OR: 0.65, 95 % CI: 0.40–1.07), were observed for TRA vs TFA.

Critical reading and the relevance for clinical practice

Although TFA still predominates, a notable finding of this study is the increase in temporal trends towards radial access for CTO PCI over the last decade.

Despite similar technical success for TRA and TFA after adjustment in this observational study, a clear selection bias exists in that TRA seems to be preferentially used in lesions of lower angiographic and procedural complexity. This notion might be further supported by the higher numbers of ad hoc PCI performed by TRA, a significantly greater tendency towards antegrade wiring, with less frequent retrograde crossing by TRA, which is perhaps consequently reflected by the significantly fewer equipment used by TRA as compared with TFA.

Two randomised trials, the COLOR (Complex Large‐Bore Radial Percutaneous Coronary Intervention) trial³ (wherein 58 % of lesions were CTO) and FORT CTO (Femoral or Radial Approach in the Treatment of Coronary Chronic Total Occlusion) trial⁴ have demonstrated similar technical success for CTO PCI via TRA vs TFA, with significantly reduced access site bleeding.

The present analysis has some important limitations, starting from its observational design, which inherently renders itself to bias. The outcomes were not adjudicated, analyses were not adjusted for multiple testing, and there is no data on use of intravascular imaging, ultrasound to secure access, crossover rates between access sites, or radial artery occlusion rates, among vascular complications.

The expertise of high-volume CTO operators incorporated in this registry also reduces the generalizability of these findings.

Despite its limitations and observational nature, this study complements the increasing body of evidence supporting the use of bi-radial access for CTO PCI, particularly in cases of lower complexity, requiring less support, and typically approached via an antegrade strategy.

References

1. Xenogiannis I, Gkargkoulas F, Karmpaliotis D, et al. Temporal trends in chronic total occlusion percutaneous coronary interventions: insights from the PROGRESS‐CTO registry. J Invasive Cardiol. 2020;32:153‐160.
2. Simsek B, Gorgulu S, Kostantinis S, et al; PROGRESS-CTO investigators. Radial access for chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry. Catheter Cardiovasc Interv. 2022 Jul 23. doi: 10.1002/ccd.30347. Epub ahead of print. PMID: 35870177.
3. Meijers TA, Aminian A, van Wely M, et al. Randomized comparison between radial and femoral Large‐Bore access for complex percutaneous coronary intervention. JACC Cardiovasc Interv. 2021;14:1293‐1303.
4. Gorgulu S, Kalay N, Norgaz T, et al. Femoral or radial approach in treatment of coronary chronic total occlusion: A randomized clinical trial. JACC Cardiovasc Interv. 2022;15:823‐830.