The authors Kim et al. [16] published a series of 150 selected
patients who had angiography or PCI with 6 French catheters via the left
box approach, 14 success rate was 88%. The main reasons were a failure
in puncture and failure in advancing the guidewire due to the tortuosity
of the artery and vasospasm. In the experience of Valsecchi et al.
[17], all 52 patients underwent diagnostic or procedural
intervention through dTRA access. The overall viability was 90%. The
failures occurred due to occlusion of the proximal radial artery and
distal hypoplastic/vasospastic artery.
In the context of performing the puncture on the patient’s left side, it
does not impose additional difficulties [18]. An observation to be
taken in these cases is that, when the patient has some degree of
respiratory distress and uses abdominal breathing more intensely, there
is a lot of hand oscillation at this time, which can prevent not the
correct palpation of the wrist, but its puncture. As for the viability
and incidence of complications, it has already been demonstrated that
there are no differences between the two sides, despite the slight
differences in favor of the radial left in terms of shorter fluoroscopy
time and less volume of contrast used [21]. This small disproportion
is not due to the fact that we find more tortuosity when navigating the
Brachiocephalic Trunk, which does not occur on the left side [22].
An advantage of the dTRA route is to preserve the conventional local
radial puncture system on the wrist, as the need for multiple procedures
on the same patient is becoming more and more frequent, due to increased
life expectancy, as well as increased comorbidities that contribute to
the development of atherosclerotic disease [22]. There is no tissue
or vascular trauma in the usual place, nor does it suffer the effects of
prolonged hemostatic compression or even with excessive intensity.
However, a relevant perception during patient selection was that, in
many individuals who had a palpable radial pulse at the wrist, the pulse
in the anatomical region. The snuff box region was very thin or
imperceptible [22].
The disadvantage of the vessel’s smaller caliber, which certainly
decreases eligibility for the technique, has led us to assume that it
may not be accessible to become a standard in cardiology interventions,
but a good option in selected cases, especially on the left side.
Another advantage that emerges from the present study is that the dTRA
access security profile is similar to the conventional TRA profile since
a minimal incidence of hemorrhagic complications was detected and there
was no pulse loss [21].
The maintenance of the wrist appears as an interesting advantage due to
the possibility of repeating the puncture in the same place, when
necessary. Due to the similarity of the advantages of the two
techniques, dTRA access can become another access route in which there
will be the possibility of early discharge, even on the same day. Data
from the Brazilian reality are already beginning to confirm the safety
of this strategy, as long as an observation period is observed,
approximately 6 hours are observed in selected patients [22].
The incidence of radial artery occlusion (RAO) and hemorrhagic events
with dTRA has not been fully elucidated. Thus, a study in Japan
investigated the effects of using dTRA on RAO and post-procedure
hemorrhage. From April 2018 to July 2018, 228 consecutive patients
undergoing coronary angiography or intervention through dTRA in two
hospitals were analyzed. The rate of RAO, changes in the diameter of the
forearm and distal radial artery, and cross-sectional area after the
dTRA (1 day and 1 month) on vascular ultrasound and incidence of
hemorrhagic complications were investigated. RAO in the forearm and
distal occurred in 1 (0.4%) and 8 (3.1%) patients in 1 month,
respectively. There were no bruises on the forearm. The ultrasound
findings indicated that the diameter of the radial artery and the
cross-sectional area was significantly larger after the dTRA (p
<0.001). The diameter of the distal radial artery and the
cross-sectional area in the anatomical snuffbox were also significantly
larger after the dTRA (p <0.001). Therefore, dTRA was
associated with a low incidence of RAO at the puncture site and in the
forearm, post-procedure dilation of the radial artery, and no
hemorrhagic complications that extended to the forearm [23].
In addition, the ldTRA approach is a new technique for coronary
intervention. This technique is convenient for specialists to operate
and is welcome for right-handed patients. The anatomical snuffbox and
the first intermetacarpal are two puncture sites available based on the
anatomy of the hand. In technical aspects, the main differences between
the left distal transradial approach and the conventional transradial
approach are the patient’s special position, puncture procedure, choice
of the sheath, and hemostasis methods. According to preliminary data,
this technique is viable and safe and has a low rate of complications,
including occlusion of the radial artery in the forearm. The left distal
transradial approach is a very promising strategy for coronary
intervention and deserves further exploration [24].
In addition, another study analyzed that dTRA is associated with reduced
rates of radial artery occlusion, ischemic events in the hands, as well
as greater patient comfort, faster periprocedural management, and cost
benefits. Our preliminary experience with dTRA for diagnostic cerebral
angiography demonstrates excellent viability and safety in combination
with relative efficiency [25].