Letters to the Editor
Trifurcating Coronary Artery Disease: As we have previously proposed,3 LM trifurcation stenting needs to
Expanding the Frontier of Interventional be reserved for patients who are at high risk of bypass surgery or
Cardiology refuse surgery as a first treatment option.
Trifurcating coronary disease involves unique coronary anatomy
We read with interest the manuscript published by Furuichi et al1 that is challenging even to the most experienced operators. Our pre-
in the April 2007 issue of the Journal of Invasive Cardiology. The viously published classification and treatment methodology2 needs
authors presented their experience with drug-eluting stents (DES) in to be validated in larger registries before we can recommend the rou-
trifurcation lesions in the coronary arteries, predominantly left main tine use of trifurcation stenting to the interventional community.
trifurcation (13 out of 15 patients). The mean follow-up period was
19.0 ± 8.3 months. The authors reported a target lesion revascular- Nicolas Shammas, MD, MS, FACC, FASCI
ization (TLR) rate of 20%, and a target vessel revascularization President and Research Director,
(TVR) rate of 40%. There were no deaths, acute stent thrombosis or Midwest Cardiovascular Research Foundation
Q-wave myocardial infarctions reported. The results overall appear Davenport, Iowa
favorable for this complex group of patients.
The authors described a nearly identical classification of trifurca- References
tion disease to the Shammas classification2,3 presented at New Car- 1. Furuichi S, Sangiorgi GM, Palloshi A et al. Drug-eluting stent implanta-
tion in coronary trifurcation lesions. J Invasive Cardiol 2007;19:157–162.
diovascular Horizons, held in New Orleans in November of 2006,4
2. Shammas NW. Trifurcating coronary artery disease: A proposed classifica-
and published earlier this year in the January and February issues of tion and treatment methodology. J Invasive Cardiol 2007;19:32–35.
the Journal of Invasive Cardiology. Also, Shammas et al published the 3. Shammas NW, Dippel EJ, Avial A. et al. Long-term outcomes in treating
first long-term follow-up report on DES in treating left main (LM) left main trifurcation coronary artery disease with the paclitaxel-eluting
stent. J Invasive Cardiol 2007;19:77–82.
trifurcation disease in the February 2007 issue of the Journal.3 In
4. Shammas NW, et al. Long term outcome in treating trifurcation coronary
both the Shammas and Furuichi manuscripts, no definite relation- artery disease with the Taxus drug eluting stent. Presented at New Cardio-
ship appears between the method of stenting and TLR or the type of vascular Horizons, New Orleans, Louisiana, November 2006.
disease distribution and complications. In the Shammas manuscript,
a forced logistic regression analysis in 20 consecutive patients with
LM trifurcation disease showed that the method of treatment or the Reply to Letter to the Editor
distribution of disease did not predict the combined endpoint of
death, acute stent thrombosis and TLR. In the manuscript by We thank Dr. Shammas for the interest he has shown our
Furuichi et al, restenosis also occurred almost equally with trifurca- manuscript. We are pleased to see that operators from highly qual-
tion stenting using the “double-crush” and the “modified-V” tech- ified centers share our interest about this complex and rare proce-
niques. It is possible that the small number of patients in both studies dure. 1,2 Unfortunately, along with the enthusiasm for such
challenging procedures, we also share some concerns about poten-
prevent a valid statistical conclusion about the relationship between
tial risks in terms of stent thrombosis, the need for extended
disease distribution as described earlier by Shammas, and similarly in antiplatelet therapy and the lack of data regarding long-term out-
Furuichi et al, and the occurrence of adverse events. We propose the comes. These concerns are even more relevant due to the fact that
development of a large multicenter registry for trifurcation coronary trifurcation lesions are frequently located in critical sites like the
artery disease to determine how the published classification and treat- left main trunk or the anterior descending artery. Regrettably, it is
ment methodology of trifurcation disease2 predict overall outcomes difficult to provide an unbiased judgment about the safety and
and major adverse events during and following treatment. efficacy of this type of procedure since it is performed in an
Finally, we believe that current data do not allow us to conclude extremely rare number of patients, as clearly witnessed by our
that trifurcation stenting is a safe procedure, as is proposed by series of 15 cases collected over a 4-year period out of more 8,000
patients. Initial enthusiasm began immediately after the arrival of
Furuichi et al.1 Trifurcation stenting is a complex procedure that
drug-eluting stents, which many thought would allow operators to
should only be performed by highly experienced operators. In our tackle any lesion and anatomy with multiple stent implantations.
busy interventional catheterization laboratory of several thousand This enthusiasm has now evolved into a more mature vision of
interventions yearly, we previously reported in 20 consecutive patients percutaneous therapies. The advantages of stent implantation in
of LM trifurcation disease an overall adverse event rate of 29.4%. comparison to bypass surgery continue to face some shortcomings
These included sudden death (5.3%), acute stent thrombosis (10%) present in each of the two approaches, and a clear winner has not
and TLR (11.8%). In the Shammas manuscript, stent thrombosis yet been declared, at least for some complex and unique anatomi-
could be attributed to delayed clopidogrel administration until shortly cal locations such as trifurcation lesions of the distal left main
after the end of the procedure in the only 2 patients who developed coronary artery. Despite some potential problems occasionally
seen with drug-eluting stent implantation such as late stent
thrombosis. Stent thrombosis with DES has been reported, however,
thrombosis and uncertainty regarding the need for double
in approximately 4% of bifurcation stenting cases, and it is more like- antiplatelet therapy,3,4 we cannot deny that the results we are pre-
ly to occur at a higher rate with trifurcation stenting. Again, larger senting are very encouraging and so far do not seem to deter from
registries are needed to determine the true rate of stent thrombosis the careful utilization of drug-eluting stents in appropriate
with trifurcation DES stenting and the overall safety of the procedure. patients with a suitable trifurcational anatomy.
284 The Journal of Invasive Cardiology
A registry collecting all these cases from different qualified centers References
would be more than welcome. We believe it could be a useful means 1. Shammas NW. Trifurcating coronary artery disease: A proposed classification
and treatment methodology. J Invasive Cardiol 2007;19:32–35.
to better recognize caveats and limitations of stenting these lesions 2. Shammas NW, Dippel EJ, Avial A. et al. Long-term outcomes in treating left main
and finally to improve our approach to this specific field. trifurcation coronary artery disease with the paclitaxel-eluting stent. J Invasive Cardiol
Antonio Colombo, MD, Shinichi Furuichi, MD 3. Stone GW, Moses JW, Ellis SG, et al. Safety and efficacy of sirolimus- and
paclitaxel-eluting coronary stents. N Engl J Med 2007;356:998–1008.
Flavio Airoldi, MD 4. Lagerqvist B, James SK, Stenestrand U, et al. Long-term outcomes with drug-
Emo Centro Cuore Columbus, Milan, Italy eluting stents versus bare-metal stents in Sweden. N Engl J Med
E-mail: firstname.lastname@example.org 2007;356:1009–1019.
The Pronto Catheter: Distal Embolization of Any the artery, underscores the need for a constant negative pressure to be
maintained by the device until the entire thrombus has been extracted.
Remaining Thrombus Fragments May Be a Risk Investigation into overcoming this risk, with emphasis on preventing
of Creating and Then Removing Negative Pressure potential embolic complications by creating and then removing suc-
tion, is warranted to improve the safety of this novel percutaneous
In patients presenting with an acute coronary syndrome, intracoro- intracoronary thrombectomy system. Aspirating the guide catheter after
nary thrombus removal is often required during percutaneous coronary removing the Pronto is a way to decrease the risk of embolization of
intervention. The Pronto (Vascular Solutions, Inc., Minneapolis, Min- any distal thrombus fragments in our experience, and this could be
nesota) catheter is a hydrophilically-coated dual-lumen catheter designed added to the deployment steps in the instructions.
for the removal of fresh, soft emboli and thrombi from vessels in the
arterial system. While the smaller-wire lumen accommodates the Ravi K. Mallavarapu, MD, Talley F. Culclasure, Jr, MD, FACC,
guidewire, the larger extraction lumen allows for removal of thrombus Erskine A. James, MD, FACC
by using the syringe through the extension line and stopcock. The Pron- Mercer University School of Medicine
to uses simple vacuum suction and has been described as a quick and Department of Internal Medicine
simple tool for the management of thrombus in the setting of acute Macon, Georgia
myocardial infarction.1,2 Although certain precautions and warnings have E-mail: email@example.com
been stated in the instructions for use, the importance of maintaining
suction during the entire procedure is not mentioned. We believe that
maintaining negative pressure once the extraction of thrombus has been References
1. Pershad A, Hoelzinger D, Patel S. Pronto catheter thrombectomy in
started is of critical importance until the process is completed. The
acute ST-segment myocardial infarction: A case series. J Invasive Car-
instructions state that blood will enter the syringe until all the vacuum is diol 2006;18:E191–194.
gone. The next step is to turn the stopcock to the “off” position. This 2. De Young MB, Kazziha S. Use of a thrombus extraction catheter
has a two-fold effect: apart from closing the syringe from the vessel (Pronto) in the treatment of acute myocardial infarction after coronary
lumen, this step also cancels the vacuum that had until then, extracted embolism post mitral valve replacement. J Invasive Cardiol
the thrombus. With such loss of negative pressure, the remaining throm- 2006;18:E273–E275.
bus in the vessel is free to embolize with no vacuum holding it. This is
crucially important with large thrombi. We believe that this potential to
cause distal embolization of any remaining fragments of thrombus in
Vol. 19, No. 6, June 2007 285