Elective placement of the Wiktor stent after coronary angioplasty

the group with a subsequent increase in creatinine kinase. These data suggest that when the patient is an appropriate candidate and the coronary anatomy is suitable, bailout stenting should be attempted immediately after failed PTCA or threatened closure.8,22,23 An individual decision must of course be made for each patient, taking into particular account ischemic complications that would be associatedwith the unsatisfactory PTCA result if left untreated.19,24 In conclusion, even when our early experience is included, overall results of bailout stenting make it an attractive alternative to emergent CABG after failed balloon angioplasty. Early bailout stenting is less likely to be associated with in-hospital ischemic events than deferred procedures. A poor angiographic result, particularly in long lesions with multiple stent implantation, should prompt consideration of semielective surgery. 1. Detre KM, Holmes DR Jr, Holubkov R, Cowley MJ, Bourassa M, Faxon DP, Dorms GR, Bentivoglio LG, Kent KM, Myler RK, and co-investigators of the National Heart, Lung, and Blood Institute’s Percutaneous Transluminal Coronary Angioplasty Registry. Incidence and consequences of periprocedwal occlusion: the 1985-1986 National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry. Circulation 1990;82:739-750. 2. Simpfendorfer C, Belardi J, Bellamy G, G&m K, Franc0 I, Hollman J. Frequency, management, and follow-up of patients with acute coronary occlusions after percutaneous transluminal coronary angioplasty. Am .I Cardiol 1987;59:267-269. 3. Ellis SG, Roubin GS, King SB III, Douglas JS Jr, Weintraub WS, Thomas RG, Cm WR. Angiographic and clinical predictors of acute closure after native vessel coronary angioplasty. Circulation 1988;77:372-379. 4. Scott NA, Weintraub WS, Carlii SF, Tao X, Douglas JS Jr, Lembo NJ, King SB III. Recent changes in the management and outcome of acute closure after percutaneous tmnsluminal coronary angioplasty. Am J Cardiol 1993;7 1: 1159-l 163. 5. Leitschuh ML, Mills RG, Jacobs AK, Ruocco NA, LaRosa D, Faxon DP. Outcome after major dissection during coronary angioplasty using the perfusion balloon catheter. Am .I Cardiol 1991;67:10561060. 6. Sigwat U, Puel J, Mirkovitch V, Joffre F, Kappenberger L. Intravascular stats to prevent occlusion and restenosis after transluminal angioplasty. N Engl J Med 1987;316:701-706. 7. Talky JD, Weintmub WS, Roubii GS, Douglas JS, Anderson HV, Jones EL, Morris DC, Liberman HA, Craver JM, Guyton RA, King SB III. Failed elective percutaneous transluminal coronary angioplasty requiring coronary artery bypass surgery. In hospital and late clinical outcome at 5 years. Circulation 1990;82: 1203-1213. 6. Roubin GS, Cannon AD, Agmwal SK, Macander PJ, Dean LS, Baxley WA, Breland J. Intracoronary stating for acute and threatened closure complicating percutaneous tmnslnminal coronary angioplasty. Circulation 1992;85:916-927.

9. De Feyter PJ, DeScheerder ID, van den Brand M, Laannan G, Suryapranata H, Sermys PW. Emergency stenting for refractory acute coronary artery occlusion during coronary angioplasty. Am J Cardiol 1990;66: 1147-l 150. 10. Hemnann HC, Buchbinder M, Clemen MW, Fischman D, Goldberg S, Leon MB, Schatz RA, T&stein P, Walker GM, Hirshfeld JW Jr. Emergent use of balloon-expandable coronary artery stating for failed percutaneous txmsluminal corenary angioplasty. Circulation 1992;86:812-819. 11. Haude M, Erbel R, Straub U, Dieti U, Schatz R, Meyer J. Results of intracoronary stats for management of coronary dissection after balloon angioplasty. Am J Cardiol 1991;67:691696. 12. Kiemeneij F, Laarman GJ, van den Wieken R, Sunuarganda J. Emergency corenary stenting with the Palmaz-Schatz stent for failed transluminal coronary angioplasty: results of a learning phase. Am Heart J 1993;126:23-31. 13. George BS, Voorhees WD III, Roubin GS, Fearnot NE, Pinkerton CA, Raizner AE, King SB III, Holmes DR, Top01 EJ, Kereiakes DJ, Hart&r GO. Multicenter investigation of coronary stating to treat acute or threatened closure after percutaneous transluminal coronary angioplasty: clinical and angiographic outcome. J Am Coil Cardiol 1993;22:135-143. 14. Haude M, Erbel R, Issa H, Stmub U, Rupprecht HJ, Treese N, Meyer J. Subacute thrombotic complications after intracoronay implantation of Palmaz-Schatz stats. Am Heart J 1993;126:15-22. 15. Nath FC, Muller DWM, Ellis SG, Rosenschein U, Chap&is A, Quain L, Zimmerman C, Top01 EJ. Thrombosis of a flexible coil coronary stent: frequency, predictors and clinical outcome. J Am CON Cardiol 1993;21:622-627. 16. Ryan TJ, Faxon DP, Gunnar RM, Kennedy JW, King SB III, Loop FD, Peterson KL, Reeves TJ, Wiiliams DO, Winters WL. Guidelines for percutaneous trans. luminal angioplasty: a.report of the ACC/AHA Task Force on assessment of diagnostic and therapeutic cardiovascular procedures (subcommittee on PICA). J Am Cd Cardial 1988;12:529-545. 17. Chesebro JH, Knatterud G, Roberts R, Borer J, Cohen LS, D&n J, Dodge HT, Francis CK, Hillis D, Ludbrook P, Markis JE, Mueller H, Passamani ER, Powers ER, Rae AK, Robertson T, Ross A, Ryan TJ, Sobel PE, Willerson J, Williams DO, Zaret BL, Braunwald E. Thrombolysis In Myocardial Infarction (TIMI) trial, phase I: a comparison between intravenous tissue plasminogen activator and inbavenous streptokinase. Clinical findings through hospital discharge. Circulation 198276: 142-154. 16. Coronary artery angiogmphic changes after percutaneous transluminal cornnary angioplasty: manual of operations. National Heart, Lung, and Blood Institute Registry, 1985-1986: Baseline form:9. 19. Pande AK, Meier B, Urban P, Moles V, Dorsaz PA, Favre J. Intracoronay electrocardiogram during coroniuy angioplasty. Am Heart J 1992124337-341, 20. Metz D, Urban P, Camenzind E, Chat&in P, Hoang V, Meier B. Improving the results of bail-out coronary stewing after failed balloon angioplasty. Cathet Cardiovasc Diagn 1994; in press. 21. Roubin GS, King SB III, Douglas JS Jr, Lemba NJ, Robinson KA. Intmcoronary stating during percutaneous tmnsluminal coronary angioplasty. Circulation 1990;81(suppl IV):IV92-IV-100. 22. Lincoff MA, Top01 EJ, Chap&is AT, George BS, Candela RJ, Muller DW, Zimmerman CA, Ellis SG. Intracoronary stating compared with conventional therapy for abrupt vessel closure complicating coronary angioplasty: a matched case control study. JAm Co11 Cardiol 1993;21:86&875. 23. Urban P, Sigwat U. The self-expanding mesh stat. In: Sigwart U, Frank GI, eds. Coronary Stats. Berlin: Springer Verlag, 1992:21-. 24. Huber MS, Mooney JF, Madison J, Mooney MR. Use of a morphologic classification to predict clinical outcome after dissection from coronary angioplasty. Am .I Cardiol 1991;68:467471.

Elective Placement of the Wiktor Stent After Coronary Angioplasty Christopher J. White, MD, Stephen R. Ramee, MD, and Tyrone J. Collins, MD ability to maximize the artery’s luminal diameter.2,3The Wiktor stent (Medtronic Interventional Vascular, San Diego, California) is one of several metallic stents in stents is to enhance the long-term patency rate of dilat- either clinical use or in clinical trials.4-15This stent is ed coronary arteries after angioplasty by reducing the composed of a single strand of tantalum wire, which is incidence of restenosis.It has been suggestedthat stents 0.005 inches in diameter, wound in a semihelical coil might have a favorable effect on restenosisbasedon their and tightly crimped on a conventional angioplasty balloon for delivery (Egure 1). The stent is 17mm in length and is mounted on a 2.5 cm long delivery balloon From the Section of Cardiology, Department of Internal Medicine, (PrimeTM,Medtronic Interventional Vascular) without a Ochsner Clinic and Alton Ochsner Medical Foundation, 1514 Jefferson covering sheath. This pilot study examines the feasibilHighway, New Orleans, Louisiana. Dr. White’s address is: Health Care ity of elective stent placement in native coronary arterInternational, Beardmore Street, Clydebank, Scotland G814DY. Manuies in patients believed to be at increasedrisk for recurscript received November 22, 1993; revised manuscript received and rent stenosis after angioplasty. accepted January 20, 1994. linical indications for vascular stents have been sought since the initial description of a stent implanC tation by Dotter in 1969.l One potential application of

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Two groups of patients were considered to be at increasedrisk for restenosisafter balloon angioplasty and thus were candidates for elective stent implantation. Twentypatients with recurrent stenosis(restenosis)after 21 prior coronary angioplasty procedure, and 8 patients in whom a suboptimal angioplasty result occurred (residual stenosis X30%) without abrupt or threatened occlusion in a de novo stenosis were included. This protocol was approved by the hospital’s institutional review board and each patient gave informed consent. Our protocol permitted placement of stents in native coronary arteries with a diameter of 3.0 to 4.0 mm. Patients were carefully screenedand excludedfor increased risk of bleeding or a left ventricular ejection fraction ~30%. Lesion exclusion criteria included left main coronary artery and saphenousvein graft stenoses,the presence of angiographically visible thrombus, abrupt or threatened occlusion (Thrombolysis in Myocardial Infarction trial 0 or 1 flow) of the dilated artery, excessive vessel tortuosity, and lesion length >15 mm. Before stent placement, heparin (5,000 to 10,000 IU) was administered as needed to maintain the activated clotting time of >300 seconds,and an attempt was made to obtain “optimal” guiding catheter seating; the original guiding catheter was exchangedat this time if necessary. The balloon-mounted stent was advanced over an 0.014- or 0.018-inch angioplasty guidewire to the target stenosisfor deployment. A suboptimal result was characterized by a residual stenosis of 230% with preserved flow (Thrombolysis in Myocardial Infarction trial 2 or 3) in a stable patient without clinical or electrocardiographic evidence of coronary ischemia after balloon angioplasty. At followup angiography, restenosis was deJinedas 250% luminal diameter narrowing at the site of stent implantation. Clinical restenosis was dejmed as recurrent ischemia with loss of the clinical benefit obtained after stent implantation. Twenty-sevenpatients received single stents and 1 patient received 2 stents. Stents were successfully delivered to the target stenosis in every case. There were no instances of stent embolization or aborted attempts at stent delivery (Figure 2). The baseline diameter stenosis for the group was 83.5 + 9.270, which was reduced to 44.8 + 15% after balloon angioplasty and reduced further to 9.2 f 11.I% after stent implantation. The average stent size implanted was 3.4 f 0.4 mm. Onepatient experienced sustained ventricular tachycardia 1 day after stent placement in the proximal lef anterior descending coronary artery for a suboptimal result due to dissection in a de novo stenosis.Thepatient was successfullyresuscitated;echocardiographyrevealed no signs of ischemia with normal anterior wall motion. Several days later the patient again had a cardiac arrest with a prolonged but success@resuscitation. Coronary

RGURE 1. Photograph

of the expanded

Wiktor

stent.

angiography was per$ormed and revealed occlusion of the stent which could not be recanalized. The patient died secondary to complications of cardiac arrest. Major bleeding complications were seen in 5 patients (18%). One elderly female patient had a nonfatal stroke after 2 months on warfarin therapy. Four patients required blood transfusions; of these, 2 required surgical repair of pseudoaneurysms,and 2 had large hematomasat the femoral accesssite. Clinical follow-up data were available in 27patients at a mean of 11.5 f 6.2 months (range 3 to 21). Followup angiography was obtained in 23 patients (85%) at 4 to 6 months after stent implantation or earlier for clinical suspicion of restenosis. Angiographic restenosis (250% diameter narrowing) was present in 7 of 23 patients (30%), and clinical restenosiswas present in 7 of 27 patients (26%). In our initial seriesof patients electively receiving the Wiktor stem, the tantalum wire coil demonstratedeffective scaffolding properties, as confirmed by other investigators.4 The successful placement of 29 consecutive stents (which includes our learning curve) without an aborted attempt or stent embolization is attributable to the “trackability” and easeof placement of this device. Excellent radiographic visibility of the tantalum wire allowed precise placement of the stent at ostial locations or distal to uninvolved sidebranches.If multiple stents are required, they may be placed end-to-end with or without overlap due to the excellent radiographic visibility of the tantalum wire. In addition, the coil design of the Wiktor stent does not preclude future guidewire and balloon accessto side branchesthat arise from stented segments(i.e., there is no “stent jail” that occurs when tubular or mesh stents are placed acrossthe ostia of side branches). The inelasticity of tantalum results in very little recoil of the stent once it has been deployed in the target artery with the in vivo recoil quantitatively measured at 3%.4 This allows stent deployment with a balloon correctly sized to the desired arterial diameter (i.e., a 3.0 mm balloon is used to deploy a 3.0 mm stent). In contrast, stent

FIGURE 2. A, baseline angiography of a restenosis lesion in the left anterior descending artery; 6, angiography after balloon predilation with an “undersized” 2.5 mm balloon; C, angiography after implantation of a 3.0 mm stent.

BRIEFREPORTS 275

deployment with the stainless steel coil stent (Giantnrco-Roubin, Cook Inc., Bloomington, Indiana) requires 0.5 mm oversized balloons (i.e., a 3.5 mm balloon is used to deploy a 3.0 mm stent).16The use of oversized balloons to deliver stents has the potential problem of creating tearsor dissectionsat the distal or proximal ends of the balloon that are not covered by the stent. Restenosisrates for a second angioplasty procedure are difficult to determine becauseof incomplete angiographic follow-up of treated patients, and they may tend to overestimate restenosis because of an overrepresentation of symptomatic patients among those restudied. The largest published series of patients with restenosis treated with a second angioplasty found that the angiographic restenosis rate was 51% in 422 of 965 patients (44%) with follow-up angiography.r7 Angiographic restenosis rates after a second angioplasty range from 32% to 41%, and clinically determined restenosis rates after a second angioplasty, which tend to underestimate restenosis,range from 26% to 48%.18-20We are encouraged by this pilot study of patients at increased risk of restenosis, with clinical and angiographic restenosis rates of 26% and 30%, respectively. In summary, the Wiktor stent functions as an effective scaffold for the dilated artery. This stent’s tantalum wire radiopacity and coil-loop configuration improve the precision and safety of stent placement. 1. Dotter CT. Transluminally-placed c&spring end arterial tube grafts: long-term patency in canine popliteal artery. Invest Radio1 1969;4:329-332. 2. Kuntz RE, S&m RD, Levine MJ, Reis GJ, Diver DJ, Bairn DS. Novel approach to the analysis of restenosis after the use of three new coronary devices. .I Am Coil Cardiol 1992;19:1493-1499. 3. Kuntz RE, S&m RD, Canxza JP, Fishman RF, Mansour M, Bairn DS. The importance of acute luminal diameter in determining restenosis after coronary atherectomy or stenting. Circu&ion 1992;86:1827-1835. 4. de Jaegere PP, Sermys PW, Bertrand M, Wiegand V, K&r G, Marquis JF, V&ix B, U&is R, Piessens J. Wiitor stent implantation in patients with restenosis following balloon angioplasty of a native coronary artety. Am .I Cardiol 1992;69:598-602. 5. Burger W, Sievert H, Steinmann J, Schrzder R, Bauer U, Vallbracht C, Htimann A, Kneissi GD, Utech A, Kobert G. Acute and mid-term experiences with

the Wiktor stent in acute complications and restenosis after coronary angioplasty. J Intervent Cardiol 1992;5:147-157. 6. Buchwald A, Unterberg C, Werner G, Voth E, Kreuzer H, Wiegand V. Initial clinical results with the Wiktor stent: a new balloon-expandable coronary ant. Clin Cardiol 1991;14:374379. 7. Sermys PW, Strauss BH, Beatt KJ, Bertrand ME, Puel J, Rickards AF, Meier B, Goy JJ, Vogt P, Keppenberger L, Sigwart U. Angiographic follow-up after placement of a self-expanding coronary autery stat. N Eng[J Med 1991;3%kl3-17. 8. Fischman DL, Savage MP, Leon MB, Schatz RA, Ellis SG, Cleman MW, T&stein P, Walker CM, Bailey S, Hirshfeld JW Jr, Goldberg S. Effect of intracomnary stating on intimal dissection after balloon angioplasty: results of quantitative and qualitative coronary analysis. J Am Coil Cardiol 1991;18: 1445-1451. 9. Ellis SG, Savage M, Fischman D, Bairn DS, Leon M, Goldberg S, Hirshfeld JW, Cleman MW, Teirstein PS, Walker C, Bailey S, Buchbinder M, Top01 EJ, Schatz RA. Restenosis after placement of P&mu-Schatz stats in native coronary arteries. Circulation 1992;86:183&1844. 10. Levine MJ, Leonard BM, Burke JA, Nash ID, Safian RD, Diver DJ, Bairn DS. Clinical and angiographic results of balloon-expandable intracoronay stents in right coronary artery stenoses. J Am Coil Cardiol 1990; 16:332-339. 11. Strauss BH, Senuys PW, de Scheerder IK, Tijssen JG, Bertrand ME, Puel J, Meier B, Kaufmann U, Staffer JC, Rickard AF, Sigwart U. Relative risk analysis of angiographic predictors of restenosis within the coronary wallstent. Circulation 1991;84:1636-1643. 12. Schatz RA, Bairn DS, Leon M, Ellis SG, Goldberg S, Hirshfeld JW, Cleman MW, Cabin HS, Walker C, Stagg J, Buchbiider M, Teirstein PS, Top01 EJ, Savage M, Perez JA, Curry RC, Whitworth H, Sousa JE, Tio F, Almagor Y, Ponder R, Penn IM, Leonard B, Levine SL, Fish RD, Palmaz JC. Clinical experience with the Pahnaz-Schatz coronary stent. Circulation 1991:83:148-161. 12. Bucx JJ, de Scheerder I, Beat K, van den Brand M, Swyapranata H, de Feyter PJ, Serruys PW. The importance of adequate anticoagulation to prevent early thrombosis after stenting of stenosed venous bypass grafts. Am Heart J 1191;121: 1389-1396. 14. Ganxtt KN, Holmes DR Jr, Roubin GS. Early outcome after placement of a metallic inhacoronary stat: initial Mayo Clinic experience. Mayo Chin Proc 1991; 66~268-275. 15. R&fart N, Langer A, Sti%ger H. Schwaz F, Reusler W, Hofmann M. Strecker stat as a bailout device following percutaneous transluminal coronary angioplasty. J Intervent Cardiol 1992;5:79-83. 16. Roubi GS, Cannon AD, Agrawal SK, Macander PJ, Dean LS, Baxley WA, Breland J. Intracoronay stenting for acute and threatened closure complicating percutaneous transluminal coronary angioplasty. Circulation 1992;85:91&927. 17. Weintraub WS, Ghazzal ZM, Douglas JS, Liberman H, Morris DC, Cohen CL, King SB III. Initial management and long-term clinical outcome of restenosis after initially successful percutaneous transluminal coronary angioplasty. Am J Cardiol 1992;70:41-55. 18. Stone GW, Rutherford BD, McConahay DR, Johnson WI., Giorgi LV, Ligon RW, Hartzler GO. A randomized trial of corticosteroids for the prevention of restenosis in 102 patients undergoing repeat coronary angioplasty. Cat/t& Cardiovast Diagn 1989;18:227-231. 19. M&r B, King SB III, Gmentdg AR, Douglas JS, Hdhnan J, Ischiiger T, Galan K, Tanker&y R. Repeat coronary angioplasty. J Am Coil Cardiol 1984;4: 463-466. 20. Quigley PJ, Hlatky MA, Hinohara T, Rendall DS, Perez JA, Phillips HR, CaIiff RM, Stack RS. Repeat p=crcutaneous transluminal coronay angioplasty and prcdictors of recurrent restenosis. Am J Cardiol 1989;63:409-413.

Limitations of Canadian Cardiovascular Society Classification of Angina Pectoris Jafna L. Cox, BA, MD, C. David Naylor, MD, DPhil, and David E. Johnstone, MD he Canadian Cardiovascular Society (CCS) classifi- concerns, including (1) the unproven assumption of T cation of angina pectoris has been widely adopted symptomatic or physiologic equivalence among diverse since its introduction in the 197Os.lRecent appraisals2q3 levels of different activities within individual angina of this classification schemehave identified a number of From the Institute for Clinical Evaluative Sciences in Ontario, and the Clinical Epidemiology Unit, Sunnybrook Health Science Centre, North York, Ontario; the Division of Cardiology, Victoria General Hospital, Dalhousie University, Halifax, Nova Scotia; and the Departments of Medicine, Surgery, and Health Administration, University of Toronto, Toronto, Ontario, Canada. Dr. Cox is a research fellow of the Heart and Stroke Foundation of Ontario, and Dr. Naylor is a career scientist of the Ontario Ministry of Health. Dr. Naylor’s address is: Institute for Clinical Evaluative Sciences in Ontario, G-Wing, 2075 Bayview Avenue, North York, Ontario, Canada, M4N 3M5. Manuscript received October 28,1993; revised manuscript received and accepted December 22, 1993.

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grades, (2) the fact that the scale is potentially cumbersomewere one to work through the full permutations of symptoms and qualifiers for each patient, and (3) the weak relation between symptom severity as captured by the scale and anatomic disease or prognosis. To highlight patients’ perceptions of their own functional limitations and to assesshow such introspection has compared with the categorization accorded by medical personnel using the CCS scale, we developed a patient disability score, a 4-grade scale that simply refers to “no, ” “mild, ” “moderate,” or “severe limitation of desired activities.” AUGUST 1. 1994