VOL 60 NOVEMBER
Circulation" CAn Official Journal ofthe cAmerican Heart
NO 5 1979
CAssociation, Inc.
EDITORIAL Percutaneous Transluminal Coronary Angioplasty ELLIOT RAPAPORT, M.D.
IN 1964 Dotter and Judkins described a new technique in which a special dilating catheter was used for transluminal compression of localized arteriosclerotic obstructions.' The procedure has since been applied by other investigators, particularly abroad, for the management of arteriosclerotic peripheral vascular disease and to obstructions in the renal arteries.2 In 1977, after a series of experiments in cadaver hearts and in canine hearts after surgical creation of coronary arterial constrictions, Dr. Andreas Gruntzig performed the first nonoperative transluminal angioplasty of coronary arteries in man.4 To accomplish this, he devised a special balloon catheter that could be placed fluoroscopically through a guiding catheter across relatively tight proximal coronary arterial obstructions. The balloon is inflated with'a half-saline, half-Renografin solution, subjecting a proximal obstructive lesion to 4-6 atmospheres of pressure. The pressure is applied for a few seconds and can be repeated several times until demonstrable improvement occurs as judged by lessening of the arterial pressure drop across the obstructive segment and by immediate arteriographic evidence of improved luminal diameter. Since this pioneering effort the procedure has been performed in more than 200 patients throughout the world.5 Most of the procedures have been done either by Dr. Griintzig or by physicians in three other centers that have collaborated closely with him and have followed a common protocol and technique (Dr. Richard K. Myler, St. Mary's Hospital, San Francisco; Dr. Simon H. Stertzer, Lennox Hill Hospital, New York; Dr. Martin Kaltenbach, University Hospital of Frankfurt, West Germany). Recently Dr. Griintzig reported his experience with this technique.6 It has created interest not only in the profession, but From the Section of Cardiology, Department of Medicine, University of California Service, San Francisco General Hospital, San Francisco, California. Address for correspondence: Elliot Rapaport, M.D., Professor of Medicine, University of California Service, San Francisco General Hospital, San Francisco, California 94110. Circulation 60, No. 5, 1979.
also among the public. Therefore, it is important to place in perspective where we stand with this innovative technique in terms of its applicability as a therapeutic tool for the management of coronary artery disease.
Grintzig has demonstrated conclusively that it is possible in some cases to dilate an atherosclerotically stenotic segment of a coronary artery, producing hemodynamic improvement that can persist for at least many months. The procedure has been applied almost exclusively to patients with discrete proximal coronary arterial obstructions and good left ventricular function. Gruintzig feels that the procedure is most appropriate in patients with single-vessel disease, or at least where the major obstruction is limited to a single vessel; approximately 80% of those in whom the procedure has been tried have had single-vessel disease. It works best when the lesions are concentric, discrete, noncalcific and are located proximally but not at the actual division of the artery in question. Therefore, only a small fraction of patients are currently candidates for this procedure about 4-5% of all patients with coronary heart disease. Experience has also shown that approximately one-third of patients cannot be dilated successfully, either because the catheter cannot be passed across a very tightly stenotic segment or because the vessel won't dilate under pressure of the balloon. Percutaneous transluminal coronary angioplasty (PTCA) is associated with an immediate, albeit small, mortality. Immediate death or death associated with emergency bypass surgery after PTCA has occurred in 1-2% of cases. Furthermore, although the follow-up has reached 21 months for the first case, the mean follow-up in reported cases at the time this editorial is being written is only about 6 months. During this follow-up period there has been an additional 2-3% mortality. A significant number of these deaths were in patients with left-main coronary artery disease, and Dr. Griintzig and his collaborators have suggested that left-main coronary artery disease may be a contraindication for the procedure, although this lesion is ideally suited technically for the performance of transluminal angioplasty.5 Nearly 10% of the patients
Downloaded from http://circ.ahajournals.org/969 at Univ of Western Ontario on April 13, 2015
970
CI RCU LATION
have required bypass surgery within hours or a day of PTCA, most apparently because complete occlusion with clinical deterioration has resulted with or immediately after, balloon compression. The actual pathologic consequences that result in luminal widening after plaque balloon compression are not fully understood. It seems likely from those cadaver and experimental studies that have been performed that successful dilatation is accompanied by splitting or rupture of the fibrous cap overlying the atherosclerotic plaque, creating a larger circumference of the vessel in that area. Late arteriographic studies have sometimes shown an actual further widening of the vessel lumen compared with that immediately after the angioplasty. This presumably reflects the ability of the body to phagocytize or otherwise remove exposed debris extending into the lumen that has previously been walled off by the fibrous cap; subsequently, endothelialization occurs and a wider channel results. However, a restenosis rate of almost 10% has been observed over a mean follow-up of approximately 6 months, so a certain number of cases that are successfully managed initially will deteriorate. To minimize this, patients are placed on immediate heparinization and given low molecular dextran as an antiplatelet aggregate drug during PTCA. The patients are continued on longterm oral anticoagulants and/or antiplatelet drugs. It is unlikely that PTCA, if limited to patients with proximal single-vessel disease and good left ventricular function, will have a major impact on the management of coronary heart disease. First, candidates for PTCA comprise a very small segment of the population with coronary heart disease. Second, it is unlikely that successful PTCA will improve overall survival for coronary heart disease. The prognosis of patients with single-vessel disease and good left ventricular function is excellent whether they are managed medically or whether saphenous vein bypass graft surgery has been performed because of unstable angina or poorly controlled chronic stable angina pectoris. The average 5-year survival for the medically treated group is 92-95%;, 8 the recent surgical literature suggests that the annual attrition rate after bypass surgery is comparable.8 Thus, PTCA may never be justified on the basis of prolonging survival, even as further experience is gained and immediate mortality decreases. However, Dr. Griintzig's early experience suggests that the procedure has been successful not only in alleviating symptoms of angina pectoris in a high percentage of patients, but also in improving perfusion to ischemic segments as judged by exercise stress tests, thallium perfusion scans and serial coronary arteriographic examination. PTCA clearly warrants further development and investigation. The carefully controlled studies of Gr-untzig and his collaborative investigators should be continued and expanded, because the procedure has the capability of improving myocardial flow and relieving coronary arterial obstruction to ischemic myocardial segments. The catheter manufacturer will only release
VOL 60, No 5, NOVEMBER 1979
the catheter under appropriate investigational use requirements, including approval of the institution's human experimentation committee, and the procedure must be considered investigative and not one whose benefit has already been established. The procedure should not be applied routinely even by experienced arteriographers. Those who follow Dr. Grutzig in the use of this technique should remember the limitations that he has placed on its use; in particular, the admonition that it should not be used in a patient who is not otherwise a candidate for coronary bypass graft surgery. This stipulation is clearly warranted, because almost 10% of patients have required subsequent emergency coronary bypass graft surgery. Further investigations should explore other applications. The possible use of PTCA in singlevessel disease with poor left ventricular function should be studied. Another area that should be studied is the observation that three of 11 patients with left main disease had a late death after PTCA despite original adequate dilatation.5 Although this initial discouraging outcome suggested to Grulntzig and his collaborators that patients with left main disease should not be candidates for PTCA, this judgment may be premature, and further controlled studies still seem warranted to insure that these initial poor results were not disparate. The application of this technique in some patients with two- or even three-vessel disease also needs further study. Another possible application was suggested at a recent conference on PTCA sponsored by the National Heart, Lung, and Blood Institute (NHLBI) held in Bethesda, Maryland pn June 15 and 16, 1979. Several in attendance felt that the technique might be applied at the time of coronary bypass surgery. Specifically, it was suggested that when distal disease prevented adequate flow after placement of a bypass graft, PTCA might be carried out in the operating room beyond the bypass graft to improve flow. However, facilities for carrying out coronary arteriography in the operating room with the capability of a high-fidelity playback video recorder would be necessary. Dr. Griintzig has introduced an exciting new approach to the management of coronary heart disease that has promise of saving some patients the necessity of coronary artery bypass surgery. The role of PTCA will emerge with careful clinical study. Progress in developing and understanding this procedure has been very encouraging. Other investigators who become involved should cooperate in the registry being developed both by the NHLBI and the initial collaborating investigators so that we may have better answers to some of the questions about PTCA as soon as possible. Some investigators have suggested that a randomized clinical trial of PTCA, comparing it with saphenous vein bypass graft surgery, should be carried out to evaluate this role. I believe any decision on the merits of such a trial are premature until several of the issues raised above are clarified. We should first gain further knowledge as a result of carefully controlled
Downloaded from http://circ.ahajournals.org/ at Univ of Western Ontario on April 13, 2015
PTCA/Rapaport
investigations carried out by a small, experienced of investigators. Once the technical problems have been reduced to a minimum and the indications, risks and complications, both early and late, are better defined, we will be better able to determine whether a large-scale clinical trial is warranted. References
group
1.Dotter CT, Judkins MP: Transluminal treatment of arteriosclerotic obstruction. Description of a new technique and a preliminary report of its application. Circulation 30: 654, 1964 2. Zeitler E, Grfntzig A, Schoop W (eds): Percutaneous Vascular Recanalization. Berlin, Springer-Verlag, 1978 3. Gruintzig AR, Kuhlmann U, Vetter W, Tutolf U, Meier B,
4. 5.
6. 7. 8.
971
Siegenthaler W: Treatment of renovascular hypertension with percutaneous transluminal dilatation of a renal-artery stenosis. Lancet 1: 801, 1978 Gruntzig A: Transluminal dilatation of coronary artery stenosis. Lancet 1: 263, 1978 Levy RI, Mock MB, Willman VL, Frommer PL: Percutaneous transluminal coronary angioplasty. Editorial. N Engl J Med 301: 101, 1979 Gruintzig AR, Senning A, Siegenthaler WE: Nonoperative dilatation of coronary-artery stenosis. N Engl J Med 301: 61, 1979 Burggraf GW, Parker JO: Prognosis in coronary artery disease. Circulation 51: 146, 1975 Kouchoukos NT: Results of surgery for disabling angina pectoris. In Coronary Bypass Surgery, edited by Rahimtoola SH. Philadelphia, FA Davis, 1977, pp 157-166
Downloaded from http://circ.ahajournals.org/ at Univ of Western Ontario on April 13, 2015
Percutaneous transluminal coronary angioplasty. E Rapaport Circulation. 1979;60:969-971 doi: 10.1161/01.CIR.60.5.969 Circulation is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231 Copyright © 1979 American Heart Association, Inc. All rights reserved. Print ISSN: 0009-7322. Online ISSN: 1524-4539
The online version of this article, along with updated information and services, is located on the World Wide Web at: http://circ.ahajournals.org/content/60/5/969.citation
Permissions: Requests for permissions to reproduce figures, tables, or portions of articles originally published in Circulation can be obtained via RightsLink, a service of the Copyright Clearance Center, not the Editorial Office. Once the online version of the published article for which permission is being requested is located, click Request Permissions in the middle column of the Web page under Services. Further information about this process is available in the Permissions and Rights Question and Answer document. Reprints: Information about reprints can be found online at: http://www.lww.com/reprints Subscriptions: Information about subscribing to Circulation is online at: http://circ.ahajournals.org//subscriptions/
Downloaded from http://circ.ahajournals.org/ at Univ of Western Ontario on April 13, 2015
Circulation" CAn Official Journal ofthe cAmerican Heart
NO 5 1979
CAssociation, Inc.
EDITORIAL Percutaneous Transluminal Coronary Angioplasty ELLIOT RAPAPORT, M.D.
IN 1964 Dotter and Judkins described a new technique in which a special dilating catheter was used for transluminal compression of localized arteriosclerotic obstructions.' The procedure has since been applied by other investigators, particularly abroad, for the management of arteriosclerotic peripheral vascular disease and to obstructions in the renal arteries.2 In 1977, after a series of experiments in cadaver hearts and in canine hearts after surgical creation of coronary arterial constrictions, Dr. Andreas Gruntzig performed the first nonoperative transluminal angioplasty of coronary arteries in man.4 To accomplish this, he devised a special balloon catheter that could be placed fluoroscopically through a guiding catheter across relatively tight proximal coronary arterial obstructions. The balloon is inflated with'a half-saline, half-Renografin solution, subjecting a proximal obstructive lesion to 4-6 atmospheres of pressure. The pressure is applied for a few seconds and can be repeated several times until demonstrable improvement occurs as judged by lessening of the arterial pressure drop across the obstructive segment and by immediate arteriographic evidence of improved luminal diameter. Since this pioneering effort the procedure has been performed in more than 200 patients throughout the world.5 Most of the procedures have been done either by Dr. Griintzig or by physicians in three other centers that have collaborated closely with him and have followed a common protocol and technique (Dr. Richard K. Myler, St. Mary's Hospital, San Francisco; Dr. Simon H. Stertzer, Lennox Hill Hospital, New York; Dr. Martin Kaltenbach, University Hospital of Frankfurt, West Germany). Recently Dr. Griintzig reported his experience with this technique.6 It has created interest not only in the profession, but From the Section of Cardiology, Department of Medicine, University of California Service, San Francisco General Hospital, San Francisco, California. Address for correspondence: Elliot Rapaport, M.D., Professor of Medicine, University of California Service, San Francisco General Hospital, San Francisco, California 94110. Circulation 60, No. 5, 1979.
also among the public. Therefore, it is important to place in perspective where we stand with this innovative technique in terms of its applicability as a therapeutic tool for the management of coronary artery disease.
Grintzig has demonstrated conclusively that it is possible in some cases to dilate an atherosclerotically stenotic segment of a coronary artery, producing hemodynamic improvement that can persist for at least many months. The procedure has been applied almost exclusively to patients with discrete proximal coronary arterial obstructions and good left ventricular function. Gruintzig feels that the procedure is most appropriate in patients with single-vessel disease, or at least where the major obstruction is limited to a single vessel; approximately 80% of those in whom the procedure has been tried have had single-vessel disease. It works best when the lesions are concentric, discrete, noncalcific and are located proximally but not at the actual division of the artery in question. Therefore, only a small fraction of patients are currently candidates for this procedure about 4-5% of all patients with coronary heart disease. Experience has also shown that approximately one-third of patients cannot be dilated successfully, either because the catheter cannot be passed across a very tightly stenotic segment or because the vessel won't dilate under pressure of the balloon. Percutaneous transluminal coronary angioplasty (PTCA) is associated with an immediate, albeit small, mortality. Immediate death or death associated with emergency bypass surgery after PTCA has occurred in 1-2% of cases. Furthermore, although the follow-up has reached 21 months for the first case, the mean follow-up in reported cases at the time this editorial is being written is only about 6 months. During this follow-up period there has been an additional 2-3% mortality. A significant number of these deaths were in patients with left-main coronary artery disease, and Dr. Griintzig and his collaborators have suggested that left-main coronary artery disease may be a contraindication for the procedure, although this lesion is ideally suited technically for the performance of transluminal angioplasty.5 Nearly 10% of the patients
Downloaded from http://circ.ahajournals.org/969 at Univ of Western Ontario on April 13, 2015
970
CI RCU LATION
have required bypass surgery within hours or a day of PTCA, most apparently because complete occlusion with clinical deterioration has resulted with or immediately after, balloon compression. The actual pathologic consequences that result in luminal widening after plaque balloon compression are not fully understood. It seems likely from those cadaver and experimental studies that have been performed that successful dilatation is accompanied by splitting or rupture of the fibrous cap overlying the atherosclerotic plaque, creating a larger circumference of the vessel in that area. Late arteriographic studies have sometimes shown an actual further widening of the vessel lumen compared with that immediately after the angioplasty. This presumably reflects the ability of the body to phagocytize or otherwise remove exposed debris extending into the lumen that has previously been walled off by the fibrous cap; subsequently, endothelialization occurs and a wider channel results. However, a restenosis rate of almost 10% has been observed over a mean follow-up of approximately 6 months, so a certain number of cases that are successfully managed initially will deteriorate. To minimize this, patients are placed on immediate heparinization and given low molecular dextran as an antiplatelet aggregate drug during PTCA. The patients are continued on longterm oral anticoagulants and/or antiplatelet drugs. It is unlikely that PTCA, if limited to patients with proximal single-vessel disease and good left ventricular function, will have a major impact on the management of coronary heart disease. First, candidates for PTCA comprise a very small segment of the population with coronary heart disease. Second, it is unlikely that successful PTCA will improve overall survival for coronary heart disease. The prognosis of patients with single-vessel disease and good left ventricular function is excellent whether they are managed medically or whether saphenous vein bypass graft surgery has been performed because of unstable angina or poorly controlled chronic stable angina pectoris. The average 5-year survival for the medically treated group is 92-95%;, 8 the recent surgical literature suggests that the annual attrition rate after bypass surgery is comparable.8 Thus, PTCA may never be justified on the basis of prolonging survival, even as further experience is gained and immediate mortality decreases. However, Dr. Griintzig's early experience suggests that the procedure has been successful not only in alleviating symptoms of angina pectoris in a high percentage of patients, but also in improving perfusion to ischemic segments as judged by exercise stress tests, thallium perfusion scans and serial coronary arteriographic examination. PTCA clearly warrants further development and investigation. The carefully controlled studies of Gr-untzig and his collaborative investigators should be continued and expanded, because the procedure has the capability of improving myocardial flow and relieving coronary arterial obstruction to ischemic myocardial segments. The catheter manufacturer will only release
VOL 60, No 5, NOVEMBER 1979
the catheter under appropriate investigational use requirements, including approval of the institution's human experimentation committee, and the procedure must be considered investigative and not one whose benefit has already been established. The procedure should not be applied routinely even by experienced arteriographers. Those who follow Dr. Grutzig in the use of this technique should remember the limitations that he has placed on its use; in particular, the admonition that it should not be used in a patient who is not otherwise a candidate for coronary bypass graft surgery. This stipulation is clearly warranted, because almost 10% of patients have required subsequent emergency coronary bypass graft surgery. Further investigations should explore other applications. The possible use of PTCA in singlevessel disease with poor left ventricular function should be studied. Another area that should be studied is the observation that three of 11 patients with left main disease had a late death after PTCA despite original adequate dilatation.5 Although this initial discouraging outcome suggested to Grulntzig and his collaborators that patients with left main disease should not be candidates for PTCA, this judgment may be premature, and further controlled studies still seem warranted to insure that these initial poor results were not disparate. The application of this technique in some patients with two- or even three-vessel disease also needs further study. Another possible application was suggested at a recent conference on PTCA sponsored by the National Heart, Lung, and Blood Institute (NHLBI) held in Bethesda, Maryland pn June 15 and 16, 1979. Several in attendance felt that the technique might be applied at the time of coronary bypass surgery. Specifically, it was suggested that when distal disease prevented adequate flow after placement of a bypass graft, PTCA might be carried out in the operating room beyond the bypass graft to improve flow. However, facilities for carrying out coronary arteriography in the operating room with the capability of a high-fidelity playback video recorder would be necessary. Dr. Griintzig has introduced an exciting new approach to the management of coronary heart disease that has promise of saving some patients the necessity of coronary artery bypass surgery. The role of PTCA will emerge with careful clinical study. Progress in developing and understanding this procedure has been very encouraging. Other investigators who become involved should cooperate in the registry being developed both by the NHLBI and the initial collaborating investigators so that we may have better answers to some of the questions about PTCA as soon as possible. Some investigators have suggested that a randomized clinical trial of PTCA, comparing it with saphenous vein bypass graft surgery, should be carried out to evaluate this role. I believe any decision on the merits of such a trial are premature until several of the issues raised above are clarified. We should first gain further knowledge as a result of carefully controlled
Downloaded from http://circ.ahajournals.org/ at Univ of Western Ontario on April 13, 2015
PTCA/Rapaport
investigations carried out by a small, experienced of investigators. Once the technical problems have been reduced to a minimum and the indications, risks and complications, both early and late, are better defined, we will be better able to determine whether a large-scale clinical trial is warranted. References
group
1.Dotter CT, Judkins MP: Transluminal treatment of arteriosclerotic obstruction. Description of a new technique and a preliminary report of its application. Circulation 30: 654, 1964 2. Zeitler E, Grfntzig A, Schoop W (eds): Percutaneous Vascular Recanalization. Berlin, Springer-Verlag, 1978 3. Gruintzig AR, Kuhlmann U, Vetter W, Tutolf U, Meier B,
4. 5.
6. 7. 8.
971
Siegenthaler W: Treatment of renovascular hypertension with percutaneous transluminal dilatation of a renal-artery stenosis. Lancet 1: 801, 1978 Gruntzig A: Transluminal dilatation of coronary artery stenosis. Lancet 1: 263, 1978 Levy RI, Mock MB, Willman VL, Frommer PL: Percutaneous transluminal coronary angioplasty. Editorial. N Engl J Med 301: 101, 1979 Gruintzig AR, Senning A, Siegenthaler WE: Nonoperative dilatation of coronary-artery stenosis. N Engl J Med 301: 61, 1979 Burggraf GW, Parker JO: Prognosis in coronary artery disease. Circulation 51: 146, 1975 Kouchoukos NT: Results of surgery for disabling angina pectoris. In Coronary Bypass Surgery, edited by Rahimtoola SH. Philadelphia, FA Davis, 1977, pp 157-166
Downloaded from http://circ.ahajournals.org/ at Univ of Western Ontario on April 13, 2015
Percutaneous transluminal coronary angioplasty. E Rapaport Circulation. 1979;60:969-971 doi: 10.1161/01.CIR.60.5.969 Circulation is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231 Copyright © 1979 American Heart Association, Inc. All rights reserved. Print ISSN: 0009-7322. Online ISSN: 1524-4539
The online version of this article, along with updated information and services, is located on the World Wide Web at: http://circ.ahajournals.org/content/60/5/969.citation
Permissions: Requests for permissions to reproduce figures, tables, or portions of articles originally published in Circulation can be obtained via RightsLink, a service of the Copyright Clearance Center, not the Editorial Office. Once the online version of the published article for which permission is being requested is located, click Request Permissions in the middle column of the Web page under Services. Further information about this process is available in the Permissions and Rights Question and Answer document. Reprints: Information about reprints can be found online at: http://www.lww.com/reprints Subscriptions: Information about subscribing to Circulation is online at: http://circ.ahajournals.org//subscriptions/
Downloaded from http://circ.ahajournals.org/ at Univ of Western Ontario on April 13, 2015
