by Emmanouil S. Brilakis, MD, PhD
Although chronic total occlusion PCI encompasses a broad and rapidly
evolving spectrum of spectacular techniques, the technique that most vividly
captures the imagination of interventionalists is the retrograde technique. In
this technique a guidewire and microcatheter are advanced to the true lumen
distal to the occlusion via a collateral vessel, facilitating CTO crossing.
Background, Reasons for Use
The retrograde approach to CTO was developed and mastered by Japanese
operators during the past decade. They first discovered that small septal
collaterals can be crossed by guidewires and small balloons with low risk of
complications and high frequency of successful wire crossing. They realized the
importance of dilating the collateral vessel to minimize the risk for equipment
entrapment. The operators highlighted the importance of keeping the retrograde
guidewire covered with a balloon catheter or microcatheter to minimize the risk
of myocardial injury during wire manipulations. They designed techniques to
enable retrograde CTO crossing, namely the controlled antegrade and retrograde
tracking and dissection (CART) and the reverse CART. Finally, the operators
designed dedicated equipment that has markedly facilitated performance of the
procedure, such as the Corsair catheter (Asahi Intecc) designed to facilitate
collateral crossing and obviate the need for balloon dilation, and the Sion and
RG3 guidewires (Asahi Intecc), which are designed for collateral crossing
(Sion) or externalization (RG3). The Corsair catheter and Sion wire are
currently commercially available in the United States, but the RG3 wire is not.
Retrograde CTO PCI is the “hottest” coronary interventional
technique currently; it is the technique most interventionalists are interested
in learning, although they are often intimidated by the potential
complications. This is likely because several steps of the retrograde
technique, such as wiring through collateral vessels, dilating the subintimal
space in CART and reverse CART, and snaring and externalizing the retrograde
guidewire, are not routinely performed in cardiac cath labs. Moreover, there is
concern that complications can occur; although in several series the retrograde
CTO PCI risk was low, unusual complications, such as septal hematoma, equipment
entrapment, coronary perforation or donor vessel injury, can occur.
In some cases the retrograde approach may be the only feasible (or the
most favorable) approach for specific CTO lesion subsets, such as ostial vessel
occlusions, long occlusions, occlusions with ambiguous proximal cap and
occlusions with diffusely diseased distal vessel. As a result, using the
retrograde approach can increase the success rate of CTO PCI to 80% to 90% or
more. Although the retrograde approach can salvage cases in which antegrade
crossing fails, it is not a substitute for strong antegrade CTO PCI skills that
are successful in the majority of cases.
Tips for Learning
First, retrograde CTO PCI is not an isolated technique but part of a CTO
PCI program. Operators wishing to embark on this area should be prepared to
spend a significant amount of time learning how to best perform these
procedures, and accept that they will have several failed cases, especially
during the early stages.
Panel A: Coronary angiography demonstrating a CTO of the mid right coronary
artery. Panel B: After failure to cross the lesion antegradely, a Fielder FC
(Asahi Intecc) guidewire was advanced retrogradely from the left anterior
descending artery through a septal collateral into the distal right coronary
artery (arrow). Panel C: The retrograde guidewire crossed the CTO into the
proximal true lumen, entered the antegrade guide catheter and was externalized.
Panel D: After stent implantation over the externalized guidewire, an excellent
final angiographic result was achieved.
Images: Emmanouil S. Brilakis, MD,
PhD; reprinted with permission.
Second, progressive and structured training is essential. Two
comprehensive, step-by-step descriptions of the procedures were published this
year (Catheter Cardiovasc Interv. 2012;79:3-19 and J Am Coll Cardiol
Cardiovasc Interv. 2012;5:1-11), which can provide a conceptual framework
for interested interventionalists. A new website (www.ctofundamentals.org)
provides extensive teaching on retrograde and other PCI-related techniques and
the ability to share angiograms from interesting CTO cases with experienced CTO
operators. However, the “read one, do one, teach one” philosophy does
not apply to retrograde CTO PCI. Attending CTO meetings, visiting laboratories
that routinely perform CTO PCI and eventually getting proctored by experienced
operators are key to shortening the learning curve and minimizing the risk for
Despite the difficulties, successful completion of first retrograde CTO
PCIs is an incredibly satisfying procedure for both the operator and the
patient. There is a “magic” in converting failing or undoable CTO PCI
cases into successes, and the retrograde approach is responsible for a large
portion of this “magic.”
Brilakis ES. Catheter Cardiovasc Interv.
Joyal D. J Am Coll Cardiol Cardiovasc Interv.
Kimura M. J Am Coll Cardiol Cardiovasc Interv.
Rathore S. Circ Cardiovasc Interv.
Saito S. Catheter Cardiovasc Interv.
Surmely JF. J Invasive Cardiol. 2006;18:334-338.
Surmely JF. Catheter Cardiovasc Interv.
Thompson CA. J Am Coll Cardiol Cardiovasc Interv.
Tsuchikane E. J Am Coll Cardiol Cardiovasc
For more information:
Emmanouil S. Brilakis, MD, PhD, is the director of the
cardiac catheterization laboratory at the VA North Texas Health Care System,
Dallas, and is associate professor of medicine at the University of Texas
Southwestern Medical Center, Dallas. He is also a Cardiology Today
Intervention Editorial Board member.
Disclosure: Dr. Brilakis receives speaker
honoraria from St. Jude Medical and Terumo; research support from Abbott
Vascular; and his spouse is an employee of Medtronic.