Catheterization and carfii'wascuIar interVIIM)
`v.63, no. 3 (Nov. 2004)
`General Collection
`W1 CABS?
`2004—11 23 1“!
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`VOLUME 63, NUMBER 3, NOVEMBER 2004
`
`Catheterization
`and
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`Cardiovaspular
`Interventions
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`Catheterization and Cardiovascular Interventions
`
`
` November 2004
`
`Percutaneous Intervention of a Bifurcating
`Saphenous Vein Graft With Simultaneous
`Dual-Limb Filter Wire Protection, Mark
`Lanzieri ....................... 307
`
`Editorial Comment: Embolic Protection Pas de
`Deux, Richard R. Heuser ............. 310
`
`Combined Catheter Ventricular Septal Defect
`Closure and Multivessel Coronary Stenting
`to Treat Postmyocardial Infarction
`Ventricular Septal Defect and Triple-Vessel
`Coronary Artery Disease: A Case Report,
`Raiaram Anantharaman, Kevin P. Walsh, and
`David H. Roberts .................. 311
`
`lntravascular Ultrasound Evaluation of
`Ruptured Plaque in the Left Main Coronary
`Artery Misinterpreted as an Aneurysm by
`Angiography, Yuxin Li, Junko Honye,
`Tadateru Takayama, and Satoshi Saito .....
`Editorial Comment: Ruptured Plaque, Peter J.
`Fitzgerald ......................
`Use of Gadobutrol in Coronary Angiography,
`Reinhard Voss, Mathias Grebe, Martin Heidt,
`and Ali Erdogan .................. 319
`Editorial Comment: Sometimes Less Is Just
`Less, Jeff Brinker ................. 323
`
`314
`
`317
`
`Feature Topic
`Flat-Panel Detectors in the Cardiac
`Catheterization Laboratory: Revolution or
`Evolution—What are the Issues?, David R.
`Holmes, Jr., Warren K. Laskey, Merrill A.
`Wondrow, and Jack T. Cusma .......... 324
`
`Volume 63- Number 3
`CORONARY ARTERY DISEASE
`
`259
`
`265
`
`267
`
`274
`
`282
`
`W S
`
`irolimus-Eluting Stents for the Prevention of
`Restenosis in a Worst-Case Scenario of
`Diffuse and Recurrent ln-Stent Restenosis,
`Gerald 8. Werner, Ulf Emig, Andreas Krack,
`Gero Schwarz, and Hans R. Figulla .......
`
`Editorial Comment: Drug-Eluting Stents for
`Secondary Prevention of Restenosis,
`Adnan Kastrati ...................
`
`Noncardiac Surgery Following Percutaneous
`Coronary Intervention, Cesar E. Mendoza,
`Salim S. Virani, Neerav Shah, Alexandre C.
`Ferreira, and Eduardo de Marchena .......
`
`Two-Year Clinical Follow-Up Results of
`Intracoronary Radiation Therapy With
`Rhenium-188-Diethylene Triamine
`Penta-Acetic Acid-Filled Balloon, Young—
`Seok Cho, Myung—A Kim, Kyung-Kuk Hwang,
`Bon-Kwon Koo, Seil Oh, ln—Ho Chae, Hyo—Soo
`Kim, Dong-Soc Lee, Byung-Hee Oh, Myoung-
`Mook Lee, Young-Bae Park, and Yun-Shik
`Choi .........................
`
`Editorial Comment: Ionizing Radiation and the
`Coronary Arteries: Is the Plot Thickening?,
`Robert S. Schwartz ................
`
`Vascular Access Site Complications With the
`Use of Closure Devices in Patients Treated
`With Platelet Glycoprotein IIb/llla Inhibitors
`During Rescue Angioplasty, Fernando
`Boccalandro, Abid Assali, Kenichi FUJISe,
`Richard W. Smalling, and Stefano Sdringola .
`
`284
`
`.
`
`Editorial Comment: Prognostic Value of the
`Flat Fluoroscopic Detector, Stephen Balter.
`
`.
`
`331
`
`Case Reports
`Pseudoperforation During Kissing Balloon
`Angioplasty, Carmelo J. Panetta, Panayotis
`Fasseas, Ganesh Raveendran, and Kirk N.
`Garratt ........................
`
`Hemodynamic Abnormalities Across an
`Anomalous Left Main Coronary Artery
`Assessment: Evidence for a Dynamic Ostial
`Obstruction, Michael J. Lim, Michael J.
`Forsberg, Richard Lee, and Morton J. Kern.
`
`.
`
`.
`
`Improved Performance of a New Thrombus
`Aspiration Catheter: Outcomes From In
`Vitro Experiments and a Case Presentation,
`Masami Sakurada, Yuji Ikari, and Takaaki
`Isshiki ........................
`
`Basic Science Review
`
`Drug-Eluting Stents for Coronary Bifurcations:
`Insights Into the Crush Technique, John A.
`Ormiston, Erin Currie, Mark W.I. Webster,
`Patrick Kay, Peter N. Ruygrok, James T.
`Stewart, Richard C. Padgett, and Monique J.
`Panther ....................... 332
`
`Editorial Comment: Bifurcational Lesions and
`the “Crush" Technique: Understanding Why
`It Works and Why It Doesn’t—A Kiss Is Not
`Just a Kiss, Antonio Colombo .......... 337
`
`Feature Topic
`Atypical Hemodynamic Manifestations of
`Cardiac Tamponade, Naveen Sharma, Vipul
`Panchal, and Vijay G. Kalaria ........... 339
`
`290
`
`294
`
`299
`
`(continued)
`
`Page 3
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`(continued from previous page)
`PEDIATRIC AND CONGENITAL HEART DISEASE
`
`PERIPHERAL VASCULAR DISEASE
`
`Case Regor‘t
`High-Output Congestive Heart Failure
`Successfully Treated With Transcatheter
`W
`Coil Embolization of a Large Renal
`Gadolinium-Based Balloon Angioplasty for
`Arteriovenous Fistula, Mark C. Bates and
`Pulmonary Artery Stenosis in an Infant With
`Ammar Almehml .................. 373
`a Ri9ht Isomerism, Hisashi Sugiyama, Toshie
`Feature Togic
`Kadono, Minako Hoshiai, Tetsushi Tan, Keiichi
`Carotid Artery Surgery vs. Stent: A
`szumi' Hajime Sakamoto, and Simpei
`Cardiovascular Perspective, Imad A.
`Nakazawa """"""""""" 346
`Alhaddad ---------------------- 377
`lnfective Endocarditis After Transcatheter
`VALVULAR HEART DISEASE
`Closure of a Patent Foramen Ovale, Marco
`.
`.
`.
`Calachanis Luisella Carrieri Roberto Grimaldi
`‘
`d es
`’
`.
`'
`.
`_
`_
`Franco VGQIIO, and Fulvio Orzan ......... 351 On ma! Stu I
`Initial Clinical Experience With Intracardiac
`h cardio ra h in Guidin Balloon Mitral
`EC °
`9
`p Y
`9
`Valvuloplasty: Technique, Safety, Utility. and
`Limitations. Nathan E. Green, Adam R.
`,
`.
`.
`Hansgen, and John D. Carroll .......... 385
`Or: Ina! Studies
`Safety and Utility of lntravascular W: Intraprocedure Guidance
`Ultrasound-Guided Carotid Artery Stenting,
`for Percutaneous Mitral Valve Interventions:
`David J. Clark, Sara Lessio, Margaret
`TTE, TEE, ICE, or X-Ray‘?, Ted Feldman.
`.
`.
`O’Donoghue, Robert Schainfeld, and Kenneth
`Rosenfield...................... 355
`LETTERS To THE EDITOR
`H J
`k,
`Ed 1‘
`-
`-
`.
`.
`.
`.
`,
`Clopidogrel Resistance, Stan Heptinsta , ac re
`W' A View From w'thm’ Davrd
`363
`R. Glenn, Jane A. May, Robert F. Storey, and
`'
`' """"""""""
`Robert G. Wilcox .................. 396
`
`.
`
`394
`
`Endovascular Treatment of the Subclavian
`Artery: Stent Implantation With or Without
`Predilatation, Max Amor, Guering Eid-Lidt,
`Zukai Chati, and James R. Wilentz........ 364
`
`The Cough That Resuscitated Dr. F. Mason
`Sone's First Patient Undergoing Selective
`Cine Coronary Arteriography, Tsung O.
`Cheng ........................ 397
`
`Editorial Comment: The Way to a Man’s Heart W
`(or Head) Is Through His Shoulder, Zoltan G.
`The Snowmass Conference: A Conversation
`Turi ......................... 371
`With Founder, Jack Vogel ............ 398
`
`Volume 63, Issue 3 was mailed the Week of October 25, 2004
`
`
`
`
`
`.WILEY-LISS
`
`A WILEY-L158, INC, PUBLICATION
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`WWILEY
`
`InterSteience®
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`This journal is onllne
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`
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`Catheterization and Cardiovascular Interventions 63:299 –306 (2004)
`
`Improved Performance of a New Thrombus Aspiration
`Catheter: Outcomes From In Vitro Experiments and a
`Case Presentation
`
`Masami Sakurada,1 MD, Yuji Ikari,2* MD, and Takaaki Isshiki,3 MD
`
`Thrombus vacuum catheter (TVAC) is a new thrombus aspiration catheter. The catheter
`has a beak-shaped distal tip and a shaft with spring support. Based on in vitro tests,
`these design features showed improved ability to pass through a simulated coronary
`artery model with a bend and to aspirate gel. TVAC has an outer diameter of 4.5 Fr and
`is available with a 7 Frguide. We report a case of acute myocardial infarction that was
`successfully treated with TVAC after use of other aspiration devices failed in its treat-
`ment. Since protection of microcirculation in coronary reperfusion may be essential in
`acute myocardial
`infarction, TVAC is a promising device to help achieve this goal.
`Catheter Cardiovasc Interv 2004;63:299 –306.
`© 2004 Wiley-Liss, Inc.
`
`Key words: acute myocardial infarction; percutaneous coronary intervention; embolism
`
`INTRODUCTION
`
`Survival rate in acute myocardial infarction has im-
`proved after introduction of thrombolysis and direct per-
`cutaneous coronary intervention (PCI). However, based
`on a meta-analysis, mortality rate is still 4.4% of those
`cases treated by direct PCI [1]. Coronary embolism is
`frequently observed in autopsy cases following PCI or
`thrombolysis [2]. In acute myocardial infarction (AMI),
`no-reflow phenomenon indicates poor prognosis even
`with successful dilatation of occluded arteries [3]. Nor-
`mal epicardial flow and normal tissue level myocardial
`perfusion are essential for low risk of mortality both in
`thrombolysis [4] and in PCI [5]. Although abnormal
`tissue level myocardial perfusion may be caused by sev-
`eral mechanisms, one of the major reasons is considered
`to be embolism of atheroma as well as thrombus. If distal
`embolism can be safely avoided, mortality rate could be
`improved. Thus, there is a need for development of
`devices that avoid distal embolism when used in treat-
`ment of AMI.
`In this report, we describe a new aspiration catheter
`named thrombus vacuum catheter (TVAC). With this
`device, simple aspiration is easy for patients with AMI.
`TVAC has a special design in the distal tip and shaft,
`which facilitates better passing and aspiration. This is the
`first report describing experimental use of this new device.
`
`MATERIALS AND METHODS
`TVAC Catheter
`TVAC (Nipro, Osaka, Japan) is an aspiration catheter
`made of polyamide-elastomer with an outer diameter of
`
`© 2004 Wiley-Liss, Inc.
`
`4.5 Fr, an inner diameter of 0.90 mm2, and a length of
`1,350 mm. The catheter has support material inside the
`lumen throughout the catheter. TVAC can be used with a
`0.014⬙ guidewire and a 7 Frguide catheter. The shape of
`the distal tip is unique in that it looks like the beak of a
`duck (Fig. 1). TVAC is connected to a collecting bottle
`with a collecting filter via a 2 m connecting tube. Just
`prior to use, the collecting bottle is connected to a vac-
`uum pump through a hydrophobic filter. The vacuum
`pump can generate negative pressures of 600 –760 mm
`Hg, which can be continuously controlled by a switch.
`
`Description of Catheters
`A comparison of the aspiration catheters is shown in
`Table I. Thrombuster (Kaneka, Osaka, Japan) and Per-
`cuSurge Export catheter (Medtronics, Minneapolis, MN)
`have larger outer diameters. TVAC and Rescue catheter
`(Boston Scientific, Natick, MA) have support wires in-
`side the tube similar to a balloon catheter. The inner
`
`1Division of Cardiology, Sekishinkai Sayama Hospital, Sayama,
`Japan
`2Division of Cardiology, Mitsui Memorial Hospital, Tokyo, Japan
`3Division of Cardiology, Teikyo University School of Medicine,
`Tokyo, Japan
`
`*Correspondence to: Dr. Yuji Ikari, Division of Cardiology, Mitsui
`Memorial Hospital, 1, Kanda-Izumi-cho, Chiyoda-ku, Tokyo 101-
`8643, Japan. E-mail: ikari-tky@umin.ac.jp
`
`Received 23 October 2003; Revision accepted 25 June 2004
`
`DOI 10.1002/ccd.20184
`Published online in Wiley InterScience (www.interscience.wiley.com).
`
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`300
`
`Sakurada et al.
`
`diameter of Thrombuster is larger due to the lack of an
`inner support wire.
`
`Gel Aspiration in a Test Tube
`One gram of gelatin was minced into pieces with an
`average diameter of 1.4 mm and placed with distilled
`water in a 3.0 mm tube made of polyvinyl chloride. The
`
`time for aspiration was measured using each catheter.
`Negative pressure was applied using the manufacturer’s
`original device. For TVAC, a Nipro model 59-080 motor
`drive was used; for Rescue, the motor drive was model
`22935-003 from Boston Scientific. A 30 ml syringe was
`used for Thrombuster and a 20 ml syringe for Percu-
`Surge. The experiment was repeated 13 times.
`
`Passing Ability Test
`Passing ability was measured using a PTCA training
`device (Medical Sense, Japan). A 7 Fr JL4 Wiseguide
`catheter (Boston Scientific) was inserted and a 0.014⬙
`BMW guidewire (Guidant,
`Indianapolice,
`IN) was
`passed into a bending left anterior descending artery
`(LAD) of the training device. TVAC was pushed with a
`constant mechanical pressure until the guide catheter was
`dislodged from the coronary ostium. The length between
`the ostium and the distal tip of the aspiration catheters
`was measured. Other aspiration catheters such as Rescue,
`PercuSurge, and Thrombuster were compared under the
`same conditions. The experiment was repeated six times
`for each catheter.
`
`Suction Efficiency for Vessel Side
`An aspiration catheter is better suited for aspiration of
`the side of vessels because some thrombi may attach to
`the vessel wall. An experiment was designed to measure
`aspiration efficiency for the sides of vessels using a
`suction attachment for the catheter tip and the side wall
`of a 4.8 mm silicone tube under negative pressure. A
`silicone tube was filled with distilled water and placed in
`a vertical position. Each catheter was connected to the
`motor drive (59-080, Nipro) and aspiration was per-
`formed at 680 mm Hg negative pressure. First, we per-
`formed this experiment using the original manufacturer’s
`device; however, it was difficult to measure the suction
`force using a syringe because of a gradual decrease of
`negative pressure. We used the same motor drive for
`each catheter rather than the original manufacturer’s de-
`vice to have consistency of experimental conditions. We
`measured the suction force directed to the side of the tube
`
`Fig. 1. Photographs of TVAC. A: Distal tip of the TVAC resem-
`bles the beak of a duck. B: TVAC system consists of a catheter
`and a vacuum motor drive.
`
`TABLE I. Comparison of Aspiration Catheters for 7 Fr Guide Catheter
`
`Guide catheter
`Larger outer diameter
`Smaller outer diameter
`Distal inner lumen (mm2)
`Proximal inner lumen (mm2)
`inner support
`shape of distal tip
`original device for negative pressure
`aspiration time in a test tube (sec)
`
`TVAC
`
`7 Fr
`4.5 Fr
`4.5 Fr
`0.9
`0.98
`yes
`duckbill
`motor drive
`20.35 ⫾ 4.07
`
`Thrombuster
`
`7 Fr
`5.7 Fr
`4.5 Fr
`1.13
`1.37
`no
`oblique straight
`30 ml syringe
`11.81 ⫾ 1.13
`
`PercuSurge
`
`7 Fr
`5.6 Fr
`3.7 Fr
`0.95
`0.92
`no
`oblique straight
`20 ml syringe
`39.50 ⫾ 6.40
`
`Rescue
`
`7 Fr
`4.5 Fr
`4.5 Fr
`0.65
`0.65
`yes
`oblique straight
`motor drive
`61.63 ⫾ 2.73
`
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`New Thrombus Aspiration Catheter
`
`301
`
`Figure 2. Passing ability test. Passing ability was measured using a PTCA training device
`(Medical Sense, Japan). Each catheter was pushed with a constant mechanical pressure until
`the guide catheter was dislodged from the coronary ostium. Average catheter position is shown
`by arrows. Average length from the ostium was measured in six experiments. Error bars show
`the standard deviation. T, Thrombuster; P, PercuSurge; R, Rescue. Asterisk represents P < 0.05
`compared to TVAC; double asterisk, P < 0.01 compared to TVAC.
`
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`302
`
`Sakurada et al.
`
`Fig. 3. Suction ability for side direction. An aspiration catheter
`was inserted into a 4.8 mm silicone tube. We measured the
`attachment force directed to the side of the tube at 680 mm Hg
`negative pressure using a handheld digital force gauge (A–C).
`TVAC attached to side wall; however, other catheter could not
`attach (D).
`
`using a handheld digital
`Shimpo, Japan).
`
`force gauge (DFG-0.2K,
`
`In Vitro Gel Aspiration of a Side Branch Embolic
`Occlusion
`TVAC is designed to aspirate both intraluminal
`thrombi and intramural atheromas. To test the ability of
`removing an atheroma with a small rupture in the fibrous
`cap from the vessel wall, we designed an in vitro exper-
`iment to remove gels from the side branch of a silicone
`tube. A vertical tube with an inner diameter of 3.5 mm
`was used as a model of a coronary artery having a side
`branch with an inner diameter of 4.8 mm (Fig. 4). A total
`of 1.2 g gelatin blocks with average diameter of 1.4 mm
`were filled in the side branch, which was used as a model
`of intramural atheroma. The size of the internal diameter
`of the side branch was 3.0 mm with a 1.5 mm opening to
`a side branch. For all experiments, a motor drive (59-080,
`Nipro) was used at an aspiration pressure of ⫺680 mm
`Hg. Each catheter was used in turn to remove the gelatin.
`The endpoint was removal of all the gelatin or all of the
`water in the container (125 ml), whichever came first. We
`compared the volume of gelatin removed, the volume of
`water removed, and the time for removal to determine the
`
`endpoint. The experiment was performed 13 times for
`each catheter.
`
`Use of TVAC in Patients With Acute Myocardial
`Infarction
`TVAC was approved by Japanese Ministry of Health,
`Labor, and Welfare in December 2002. After the ap-
`proval, we performed aspirations using TVAC.
`
`RESULTS
`Test Tube Gel Aspiration
`The results of aspirations are shown in Table I. The
`aspiration time of Thrombuster was the shortest, and
`TVAC and PercuSurge were shorter than Rescue. This
`experiment seemed highly dependent on the inner lumen
`diameter of the catheter.
`
`Passing Ability
`Quantitative measurements of passing ability is shown
`in Figure 2. Only TVAC was able to pass the third bend.
`PercuSurge and Thrombuster catheters were able to
`reach the second bend. The Rescue catheter was only
`able to pass the first bend.
`
`Suction Efficiency at Side of Vessel
`Under negative pressure, TVAC could attach to the
`side wall of a silicone tube; however, the other catheters
`could not attach (Fig. 3).
`
`In Vitro Gel Aspiration of a Side Branch Embolic
`Occlusion
`This experiment was performed as shown in Figure 4.
`TVAC was able to aspirate all the gelatins in every
`experiment (Fig. 5). PercuSurge or Rescue catheters as-
`pirated only water. Thrombuster catheter aspirated all the
`gelatins in 4 of the 13 experiments. The aspiration time
`of TVAC was significantly shorter than any of the others,
`and the aspirated gelatin volume of TVAC was signifi-
`cantly greater than the other catheters. Furthermore, as-
`pirated water volume of TVAC was less than the others.
`
`CASE REPORT
`
`A 62-year-old man with hypertension awoke in the
`middle of night due to severe chest pain and dyspnea and
`was admitted to our emergency department 1 hr after the
`onset of symptoms. AMI was strongly suspected and
`emergency cardiac catheterization was performed.
`A 7 Fr sheath was placed in the right radial artery.
`Coronary angiography revealed total occlusion of the
`distal right coronary artery (RCA; Fig. 6A) and 75%
`stenosis in the middle portion of the left circumflex
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`Fig. 4. Gel aspiration in a side branch embolic occlusion. To test the aspiration ability of
`intramural atheroma through rupture of fibrous cap, we designed an in vitro model. A silicone
`tube of inner diameter 3.5 mm with a 1.5 mm opening to a side branch of inner diameter 4.8 mm
`was filled with water. The hole and gels in the side branch were used to simulate a rupture in
`a fibrous cap and intramural atheroma. The experiment was repeated 13 times for each
`catheter.
`
`artery. Because a heavy thrombus burden was suspected
`based on the ectasia of the right coronary artery, we
`decided to perform aspiration therapy with a distal pro-
`tection device to avoid distal embolism.
`After administration of 10,000 units of heparin, a 7 Fr
`Judkins Right 4 guiding catheter (Boston Scientific) was
`inserted into the right coronary ostium. A 0.014⬙ Percu-
`Surge guard wire was advanced carefully across the totally
`occluded lesion. A platelet GP IIb/IIIa inhibitor was not
`used because it is not available in Japan. The protection
`balloon was placed 3 or 4 cm distal to the occluded site and
`dilated up to 4 mm. A PercuSurge Export catheter was tried
`but could not be pushed past the occlusion site. Thus,
`
`coronary flow was still at Thrombolysis in Myocardial
`infarction (TIMI) grade 0 after the use of PercuSurge Ex-
`port catheter with only little of the thrombus aspirated.
`Another 0.014⬙ extrasupport BMW guidewire (Guidant)
`was inserted for a double-wire technique. However, the
`PercuSurge Export catheter also failed to pass the lesion.
`Next, we tried a Thrombuster aspiration catheter.
`Again, the Thrombuster catheter was unable to pass the
`mid portion of RCA because the tip of the catheter bent
`at this site and never reached the distal RCA.
`At this point, we tried TVAC and successfully passed
`the lesion proximal to the PercuSurge Guardwire balloon
`(Fig. 6B) and were able to aspirate a red thrombus
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`Fig. 5. Results of aspiration in a side branch embolic occlu-
`sion. Top: PercuSurge or Rescue catheters could not aspirate
`gelatin in this model. In contrast, TVAC could aspirate the entire
`gelatin in all 13 experiments. Thrombuster catheter could aspi-
`rate the entire gelatin in 4 out of 13 experiments. Middle: Aspi-
`ration time was the shortest with TVAC. Bottom: Aspirated
`water volume was smallest with TVAC. Asterisk represents P <
`0.05 compared to TVAC; double asterisk, P < 0.01 compared to
`TVAC.
`
`(Fig. 6C). After TVAC thrombus aspiration, coronary
`flow improved to TIMI 3. A Tristar 2.75 ⫻ 23 mm stent
`was deployed to the remaining hazy tight stenosis. After
`the stent deployment, coronary angiography revealed an
`intraluminal atheroma, which may have resulted because
`the intramural atheroma was squeezed into the lumen by
`
`stent deployment. The TVAC catheter was advanced
`over the wire again far beyond the stent to the level of the
`distal part of posterolateral branch and to the occluded
`posterior descending artery. The intraluminal atheroma
`was successfully aspirated with TVAC. Final angiogra-
`phy after repeated aspiration revealed almost no residual
`stenosis, no dissection, and TIMI 3 flow was established
`in the distal coronary bed with a normal myocardial
`perfusion grade (Fig. 6D). The peak CK was 3,292 U/L.
`The patient recovered without complications and was
`discharged from the hospital 12 days after the procedure
`in stable condition.
`
`DISCUSSION
`
`In this report, we described a new aspiration catheter
`named TVAC. TVAC has a narrower inner lumen com-
`pared to Thrombuster, which does not have an inner
`support wire. However, the aspiration ability in a com-
`plex coronary model is better than other wide lumen
`catheters. The side suction was demonstrated by experi-
`ments in a coronary side branch model as well as suction
`attachment to a tube. This is probably because of the
`unique distal tip that is shaped like the beak of a duck.
`Negative pressure at the unique distal tip may generate
`turbulent flow that results in suction from all directions.
`Furthermore, the ability to pass a lesion is better than
`other catheters because of the support wire. This desir-
`able outcome was actually shown in the case report since
`the case was successfully treated by TVAC after failure
`of the other types of aspiration catheters.
`Mortality rate has improved in patients with AMI
`treated by direct PCI [1,6 –9]. Tissue level myocardial
`perfusion as well as normal epicardial flow (TIMI 3 flow)
`is required for low risk of mortality [4,5]. Although
`abnormal tissue level myocardial perfusion is caused by
`several mechanisms, one of the major reasons is consid-
`ered to be embolism of thrombus or atheroma [10]. If
`distal embolism is safely avoided, mortality could be
`better than direct PCI. Thus, there is need for develop-
`ment of distal protection devices for treatment of
`AMI [11].
`Distal protection potentially protects microperfusion
`of myocardium. Several distal protection devices have
`already been described such as filter device, balloon
`occlusion device, and aspiration device. However, at
`present, each device has weaknesses in design. Filter
`devices are still big enough to cause embolism at the first
`passage. Balloon occlusion devices are not big, but the
`occlusion makes it difficult to place stents at the correct
`position. Furthermore, the possibility of ischemia due to
`balloon occlusion cannot be ignored. Aspiration device
`have had problems in the ability to pass thrombus and
`aspiration efficiency. It is still unclear which is the best
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`Fig. 6. Coronary angiography of a 62-year-old man with AMI revealed a total occlusion at distal
`RCA (A). After passage failure with Thrombuster and PercuSurge Export catheter, TVAC suc-
`cessfully passed through the lesion (B). Red thrombus was aspirated by TVAC (C). Final
`coronary angiography revealed TIMI 3 flow without residual stenosis. Myocardial perfusion was
`assessed as grade 3 (D).
`
`device for use in AMI to preserve tissue level myocardial
`perfusion. TVAC has an improved ability to pass and to
`aspirate thrombus and is likely the best aspiration cath-
`eter available at present.
`This study compared aspiration devices consisted of a
`single tube. At present, X-Sizer (a helix cutter within a
`
`catheter tip) and Possis rheolytic thrombectomy catheter (a
`dual tube) are available as coronary aspiration devices. The
`passing ability of TVAC seems to be better because of the
`simple design. However, passing ability as well as aspira-
`tion ability of the single-tube devices should be quantita-
`tively compared with the other aspiration devices.
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`Every aspiration device may potentially cause distal
`embolization by pushing the atheroma while crossing the
`lesion. Thus, the device described here still needs to be
`tested in the clinical area. A multicenter randomized trial
`is required to test the efficacy in patients with AMI.
`
`ACKNOWLEDGMENTS
`
`The authors thank Mr. Satoru Mori for preparation and
`assistance of in vitro experiments and Mr. Yoshihiko
`Sano and Mr. Yuichi Kataishi for their expert comments.
`
`REFERENCES
`
`1. Michels KB, Yusuf S. Does PTCA in acute myocardial infarction
`affect mortality and reinfarction rates? a quantitative overview
`(meta-analysis) of the randomized clinical trials. Circulation 1995;
`91:476 – 485.
`2. Saber RS, Edwards WD, Bailey KR, McGovern TW, Schwartz
`RS, Holmes DR Jr. Coronary embolization after balloon angio-
`plasty or thrombolytic therapy: an autopsy study of 32 cases. J Am
`Coll Cardiol 1993;22:1283–1288.
`3. Ito H, Maruyama A, Iwakura K, Takiuchi S, Masuyama T, Hori
`M, Higashino Y, Fujii K, Minamino T. Clinical implications of the
`“no reflow” phenomenon: a predictor of complications and left
`ventricular remodeling in reperfused anterior wall myocardial
`infarction. Circulation 1996;93:223–228.
`4. Gibson CM, Cannon CP, Murphy SA, Ryan KA, Mesley R,
`Marble SJ, McCabe CH, Van De Werf F, Braunwald E. Relation-
`ship of TIMI myocardial perfusion grade to mortality after ad-
`
`ministration of thrombolytic drugs. Circulation 2000;101:125–
`130.
`5. Stone GW, Peterson MA, Lansky AJ, Dangas G, Mehran R, Leon
`MB. Impact of normalized myocardial perfusion after successful
`angioplasty in acute myocardial infarction. J Am Coll Cardiol
`2002;39:591–597.
`6. Every NR, Parsons LS, Hlatky M, Martin JS, Weaver WD. A
`comparison of thrombolytic therapy with primary coronary angio-
`plasty for acute myocardial infarction: Myocardial Infarction Tri-
`age and Intervention investigators. N Engl J