Author + information
- Sunil V. Rao, MD∗ (, )
- James Nolan, MBChB, MD,
- Douglas G. Fraser, MD,
- Mamas A. Mamas, BM, BCh, MA, DPhil,
- Olivier F. Bertrand, MD, PhD,
- Samir B. Pancholy, MD,
- Ivo Bernat, MD,
- Surya Dharma, MD, PhD,
- Sasko Kedev, MD, PhD,
- Sanjit S. Jolly, MD, MSc and
- Marco Valgimigli, MD, PhD
- ↵∗The Duke Clinical Research Institute, 508 Fulton Street (111A), Durham, North Carolina 27705
We read with great interest and concern the paper by Le May et al. (1) regarding the role of radial approach in patients with acute coronary syndrome (ACS). Our concerns are due to their inappropriate interpretation of clinical trial data and spurious arguments against radial access that runs of the risk of slowing the adoption of transradial procedures and thus potentially lead to increased adverse outcomes among high-risk patients undergoing percutaneous coronary intervention.
The concerns of Le May et al. (1) over multiple comparisons in the MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX) trial are unfounded. While there are several techniques to account for multiple comparisons, the Bonferroni-Holm correction, which was pre-specified in the MATRIX trial (2), is by far the most conservative one. In the MATRIX trial, radial approach significantly reduced the incidence of 30-day net adverse clinical events (NACE) (p = 0.009). These results are robust even when accounting for 4 comparisons. In addition, many of the large seminal trials of acute coronary syndromes have included both non–ST-segment elevation myocardial infarction (NSTEMI) and ST-segment elevation myocardial infarction (STEMI) patients (3). The correct interpretation of subgroups is to use interaction p value to determine consistency of benefit in subgroups and the benefit was consistent in both NSTEMI and STEMI in MATRIX. In addition, randomization in the MATRIX trial was stratified according to NSTEMI or STEMI presentation. Taken together, the available trials strongly demonstrate that transradial intervention (TRI) is superior to femoral approach in ACS patients regardless of presentation. Regarding the effect of center volume, the beneficial effect of radial approach was more pronounced at centers with high radial volume in the RIVAL (RadIal Vs femorAL access for coronary intervention) and MATRIX trials. The positive interaction term by center volume demonstrates that the primary effect may be affected to some degree by the subgroup—in other words, the results of the MATRIX trial stand alone and the finding in the subgroups of center radial volume demonstrate that centers that perform a high proportion of TRI realize its greater benefits—a finding that is completely consistent with the volume-outcome relationship for cardiovascular procedures. There was no significant difference in the use of glycoprotein IIb/IIIa inhibitors between the radial and femoral groups in the MATRIX trial, and the benefit of radial access was irrespective of glycoprotein IIb/IIIa inhibitor use. Finally, a commonly held belief among interventional cardiologists is that vascular closure devices (VCDs) reduce bleeding, and Le May et al. (1) repeat this misconception in their review. The ISAR-CLOSURE (Instrumental Sealing of ARterial puncture site—CLOSURE device vs manual compression) trial showed that VCDs were noninferior, not superior, to manual compression with respect to 30-day vascular complications (4). The added cost of VCDs is not justified when their outcomes are either no better or worse than manual compression.
The randomized trial data clearly support the use of radial access in patients with ACS undergoing angiography or intervention. Given the robustness of the data, performing more randomized trials, such as the SAFARI STEMI (Femoral vs. Radial Access For Primary PCI) trial, which is one-third the size of the MATRIX trial and is most likely underpowered for the primary outcome, is unlikely to be informative. Instead, effort should be directed at increasing the adoption of radial approach and ensuring proficiency with the procedure using “best practices” as the foundation (5).
Please note: This manuscript was prepared without external funding. Dr. Rao has received research grant support from Bellerophon and consulting honoraria from AstraZeneca, Medtronic, Terumo Interventional Systems, Merck, and CSI. Dr. Pancholy has served as a consultant for Terumo. Dr. Valgimigli has received research grant support from The Medicines Company and Terumo. All other authors have reported that the have no relationships relevant to the contents of this paper to disclose.
- American College of Cardiology Foundation