Dr. Doğan Şen

Name of the study:
Comparison of Puncture Success Rates Between Distal Radial Access and Transradial Access in Patients with ST-Elevation Myocardial Infarction

Published in Congress: TCT 2024

Link:  https://www.tctmd.com/slide/comparison-puncture-success-rate-between-distal-radial-access-and-transradial-access-patients

Introduction:

Guidelines suggest transradial access (TRA) as a way to reduce bleeding complications and mortality in the setting of ST-elevation myocardial infarction (STEMI); however, evidence supporting the use of distal radial access (DRA) is limited. Historically, TRA has been the standard access route for PCI in STEMI patients aimed at minimizing bleeding complications and reducing mortality rates. Nevertheless, evidence for DRA in emergency STEMI scenarios remains scarce.

Objective:

The evidence supporting the use of DRA in STEMI patients requiring emergency procedures is limited. The DRAMI study, conducted by operators with at least 100 cases of experience in distal radial access across three hospitals, aims to fill this gap. The objective of the study is to evaluate the puncture success rate between DRA and TRA.

Methods:

The study included 389 patients aged 19 and older diagnosed with STEMI and planned for PCI, with palpable distal radial and radial arteries, from three hospitals. Out of the initially screened 389 patients, 354 (mean age 63.3 years; 80.8% male) were randomized into DRA or TRA groups. After screening and exclusions, 178 patients were assigned to TRA and 176 to DRA, with analyses performed according to treatment intent, per-protocol, and as-treated approaches. The primary endpoint of the study was the puncture success rate, while secondary endpoints included coronary angiography (CAG) and PCI success rates, bleeding complications, puncture time, procedure time, fluoroscopic time, fluoroscopic dose, hemostasis time, and one-month major adverse cardiac events (MACE) including all-cause mortality, any myocardial infarction (MI), and any revascularization.

Results:

The likelihood of the initial access being from the left side was higher in distal access compared to conventional access (91.5% vs. 60.7%), and more contrast was used for distal access (median 150 mL vs. 140 mL; P = 0.014). Other procedural characteristics were similar between the two groups, with 5.4% switching to an alternative access site, including 2% to the femoral artery. No differences were observed in puncture time, procedure length, fluoroscopy time or dose, or hemostasis time. The primary endpoint showed a puncture success rate with a noninferiority margin of 5.65%. This rate was slightly lower in the distal radial group, and the risk difference did not confer superiority in the as-treated analysis (-1.17%; 95% CI -5.56 to 3.22; P = 0.023). During one month of follow-up, one patient experienced radial artery occlusion (in the conventional group), and one patient developed hand swelling or pain (in the distal group). Three cases of neuropathy were reported: one after distal radial access and two after conventional access. The risks of MACE (all-cause mortality, any MI, or any revascularization) and individual components were not significantly different based on access type (all P > 0.05).

Conclusion:

In this multicenter RCT trial in patients with ST-elevation myocardial infarction, puncture success rate of DRA compared to TRA was inconclusive in intention-to-treat and per-protocol analysis, but signicantly non-inferior in as-treated analysis.

Comment:
The DRAMI study has shown that the puncture success rate of Distal Radial Access (DRA) is not lower than that of Transradial Access (TRA) in treatment and per-protocol analyses. Moreover, due to the insufficient data on distal radial access in STEMI patients in previous studies, the DRAMI study is clinically significant. However, well-designed, large-scale randomized controlled trials are needed to validate the results of DRAMI. While clinicians may feel comfortable with radial access in rapid STEMI procedures, distal radial access requires more expertise, greater experience, and can take longer in some centers. Therefore, the results of DRAMI may not change clinicians' practices and may not encourage the use of distal radial access as the default approach in STEMI patients.