Catheterization and Cardiovascular Diagnosis 27:165-166 (1992)
Editorials The “Coming Out” of Coronary Balloon Angioplasty Bernhard Meier, MD Fifteen years ago, Andreas Gruentzig introduced coronary balloon angioplasty timidly for a highly select group of patients with coronary artery disease [ 11. It took him several months to find a suitable patient, from the moment he was ready. Coronary angioplasty has since evolved to become the commoner of the 2 coronary revascularization procedures in many institutions. At our hospital, it is currently recommended to over 50% of patients undergoing coronary angiography for suspected or known coronary artery disease, compared with less than 20% that are referred for coronary artery bypass surgery [2]. However, this represents more a widening of indications towards cases previously treated medically than towards the realm of bypass surgery, i.e., patients with multivessel disease. Just as 10 years ago, we still send roughly 50% of patients with triple vessel disease for bypass surgery [2]. The recommendations for angioplasty in these patients increased from 10% to 25% but this was entirely at the cost of medical treatment. The patients with triple vessel disease accepted for angioplasty are primarily those with involvement of secondary branches or those in whom single vessel treatment is deemed adequate. The percentage of multivessel angioplasty in a single session at our center has remained stable for many years between 10% and 20% [ 3 ] . In single vessel disease, recommendations for angioplasty have increased from 45% in 1983 to 78% in 1990 [2], again mainly at the expense of medical treatment. Overall, indications for angioplasty have increased from 27% to 54% between 1983 and 1990, while indications for bypass surgery and medical treatment have decreased from 28% to 18% and from 45% to 28%, respectively. This trend accounts for the general increase in angioplasty worldwide without signifying a true enlargement of the potential of the method. Single lesion angioplasty even nowadays comprises over 95% of procedures in the United States [4]. These patients seem to benefit from angioplasty compared with medical therapy solely in terms of better exercise performance [5]. On the other hand, their risk to be balanced against the clinical benefit is small, and emergency surgery is rarely indicated. This obviates the need for surgical standby in the majority of these cases [6]. The more completely and the earlier the population 0 1992 Wiley-Liss, Inc.
with suspected coronary artery disease will be subjected to coronary angiography , the more patients with isolated lesions will be found to increase the number of angioplasties as opposed to bypass operations. Yet, this dominance will not rid coronary angioplasty of the stigma of being a second class therapy in terms of results. Angioplasty, a nonsurgical intervention, is very popular with patient candidates. Among cardiac surgeons and a number of other physicians, it suffers from the connotation of being a clumsy attempt to obtain coronary revascularization that could be achieved more efficiently by bypass surgery. It may be tolerated if it succeeds but it is unforgivable if it fails. The interventional cardiologist sometimes feels like the handy man, told that he should not use the nearby shaky kitchen stool to change the light bulb but rather fetch the sturdy ladder from the basement. If he gets away with using the kitchen stool, he will be called “just lucky” and nobody will praise his courage and skill. If he falls, he will have to bear with the blame of having been stupid and stubborn on top of the broken arm. When will somebody turn up with the proof that carrying the bulky ladder up and down the basement stairs may be more dangerous than fixing the bulb on the kitchen stool? In a way, this is exactly what the paper on salvage angioplasty by Morrison et al. [7] in this issue does. It shows that the cumulated risks of the “safe” way may be worse than the apparently high risk of the “unsafe” way. The expansion of indications for angioplasty proposed by these authors may well be numerically negligible. Ideologically, it is of utmost importance. It is a “coming out” of coronary balloon angioplasty . Not infrequently, the angioplasty operator is confronted with a patient whose clinical problem resides on a single critical lesion. It is obvious that dilatation of this lesion will considerably improve the patient’s symptoms or even render him asymptomatic. But it is also obvious that an acute occlusion is likely to be fatal. The advent of
From the Cardiology, University Hospital, Bern, Switzerland.
Address reprint requests to, Bernhard Meier, MD, Professor and Head of Cardiology, University Hospital, 3010 Bern, Switzerland.
166
Editorial
percutaneous cardiopulmonary support [8] does not resolve the issue because of its short-lived protection and intrinsic complications (groin problems may induce coronary occlusion after removal of the support system). If the lesion in question is a complex and long left main stem stenosis, the risk of angioplasty is clearly worse than that of bypass surgery and the latter has to be advocated. If the problem is a short and concentric stenosis in a large left main stem, the risk of an acute and irreversible occlusion after angioplasty is probably less than 5%. Even if such a complication is a priori considered fatal, the risk of mortality is comparable to that of elective bypass surgery for left main stem disease. We are not ready yet to take on this kind of patient for angioplasty, yet we probably should. If the patient has a single culprit lesion, a poor left ventricular function, and is in generally poor health, the projected risk of bypass surgery may amount to more than 20% as indicated for the cases of Morrison et al. [7]. Dilating his short and concentric culprit lesion should have a clearly lower risk of mortality, even if the lesion is in a so-called last remaining vessel. Morrison et al. are telling us that these patients and perhaps even those with less ideal and up to 3 lesions should be accepted for angioplasty and that it may even be unethical not to do so. Are they seeing things too optimistically? First, their prospective estimates of surgical mortality may be found exaggerated by many a surgeon. On the one hand, the estimates are based on figures derived from actual and recent cases [9]. On the other hand, what is commonly referred to as “VA bashing” may discard the results of these cases as being too far from the gold standard to be seriously considered. The truth is that the vast majority of bypass operations (and angioplasty procedures for that matter) are performed in centers much more comparable with those used as a reference than with the super-specialized high-class institutions claiming superior results. Second, the relatively short follow-up tends to underestimate serious angioplasty complications. They may well be limited to the immediate phase after the intervention. The high recurrence rate, however, frequently imposes reinterventions with a new, definite risk of serious complications and mortality. The fact that the surgical series used as a reference only include the 30 day mortality is not an excuse. Surgery has a much lower rate of reinterventions. Third, the 2 patients dilated for acute myocardial infarction stray from the rest of the cohort. It is generally accepted and even recommended to attempt angioplasty on occluded vessels visualized early during an acute infarction, even if the risk of elective angioplasty of the same vessel would have been deemed excessive while it was still patent. The lesson we learn from the brave and pioneering
efforts of Morrison et al. [7] is that angioplasty is about to come out of hiding in the shadow of bypass surgery. No longer is it merely an acceptable technique for cases that are not sick enough to merit surgery and very easy cases for surgery. Suddenly, it claims to be the better solution for a small but worrisome group of patients in dire need of revascularization. Yes, angioplasty does carry considerable mortality in this group but it offers better odds than either surgery or medical treatment. The notion of being the new ultimate provider, rather than someone who more or less illicitly snatches the patient away from the conventional ultimate provider, is bound to be a psychological incentive for the interventional cardiologist grappling to cope with a mortality rate so far unknown except with high-risk surgery. It is important to state that unstable angina is not necessarily a prerequisite for angioplasty in such patients but angina refractary to therapy is. Of the new devices, only the stent is of real help, since it is of significant benefit in dealing with the problem of acute occlusion, the single largest worry with these kinds of patients. The “coming out” of coronary balloon angioplasty has long been overdue. The paper of Morrison et al. may not accomplish this process but it may well be the igniting spark.
REFERENCES I . Griintzig A: Transluminal dilatation of coronary artery stenosis. Lancet 1:263, 1978. 2 . Pande AK, Meier B, Rutishauser W: Implications of coronary angiography in patients with suspected or known coronary artery disease. Int J Cardiol (in press). 3. Meier B: Indications of coronary angioplasty and bypass surgery. Schweiz Med Wschr (in press). 4. Topol El, Ellis SG, Bates ER, Muller DWM, Schork N, Schork MA: Analysis of coronary angioplasty practice in the United States using a private insurance database. J Am Coll Cardiol 19:13A, 1992 (abstract). 5 . Parisi AF, Folland ED,Hartigan P, on behalf of the Veteran Affairs ACME Investigators: A comparison of angioplasty with medical therapy in the treatment of single-vessel coronary artery disease. N Engl J Med 326:lO-16, 1992. 6. Meier B, Urban P, Dorsaz PA, Favre J: Surgical standby for balloon angioplasty. JAMA 268:741-745, 1992. 7. Morrison DA, Barbiere CC, Johnson R , Marshall G , Fullerton G , Hammermeister KE, Grover FL, Morgan P, Olsen MA, Stovall JR, West E, Wolf D: Slavage angioplasty: an alternative to high risk surgery for unstable angina. Cathet Cardiovasc Diagn 27:169178, 1992. 8. Shawl FA, Doumaski MJ, Punja S, Hernandez DJ: Percutaneous cardipulmonary bypass support in high-risk patients undergoing percutaneous transluminal coronary angioplasty. Am J Cardiol 64: 1258-1 263, 1989. 9. Grover FL, Hammermeister KE, Burchfiel C, and the VA Surgeons: Initial report of the Veterans Administration Preoperative Risk Factor Assessment Study for Cardiac Surgery. Ann Thorac Surg 50:12-28, 1991.
Editorials The “Coming Out” of Coronary Balloon Angioplasty Bernhard Meier, MD Fifteen years ago, Andreas Gruentzig introduced coronary balloon angioplasty timidly for a highly select group of patients with coronary artery disease [ 11. It took him several months to find a suitable patient, from the moment he was ready. Coronary angioplasty has since evolved to become the commoner of the 2 coronary revascularization procedures in many institutions. At our hospital, it is currently recommended to over 50% of patients undergoing coronary angiography for suspected or known coronary artery disease, compared with less than 20% that are referred for coronary artery bypass surgery [2]. However, this represents more a widening of indications towards cases previously treated medically than towards the realm of bypass surgery, i.e., patients with multivessel disease. Just as 10 years ago, we still send roughly 50% of patients with triple vessel disease for bypass surgery [2]. The recommendations for angioplasty in these patients increased from 10% to 25% but this was entirely at the cost of medical treatment. The patients with triple vessel disease accepted for angioplasty are primarily those with involvement of secondary branches or those in whom single vessel treatment is deemed adequate. The percentage of multivessel angioplasty in a single session at our center has remained stable for many years between 10% and 20% [ 3 ] . In single vessel disease, recommendations for angioplasty have increased from 45% in 1983 to 78% in 1990 [2], again mainly at the expense of medical treatment. Overall, indications for angioplasty have increased from 27% to 54% between 1983 and 1990, while indications for bypass surgery and medical treatment have decreased from 28% to 18% and from 45% to 28%, respectively. This trend accounts for the general increase in angioplasty worldwide without signifying a true enlargement of the potential of the method. Single lesion angioplasty even nowadays comprises over 95% of procedures in the United States [4]. These patients seem to benefit from angioplasty compared with medical therapy solely in terms of better exercise performance [5]. On the other hand, their risk to be balanced against the clinical benefit is small, and emergency surgery is rarely indicated. This obviates the need for surgical standby in the majority of these cases [6]. The more completely and the earlier the population 0 1992 Wiley-Liss, Inc.
with suspected coronary artery disease will be subjected to coronary angiography , the more patients with isolated lesions will be found to increase the number of angioplasties as opposed to bypass operations. Yet, this dominance will not rid coronary angioplasty of the stigma of being a second class therapy in terms of results. Angioplasty, a nonsurgical intervention, is very popular with patient candidates. Among cardiac surgeons and a number of other physicians, it suffers from the connotation of being a clumsy attempt to obtain coronary revascularization that could be achieved more efficiently by bypass surgery. It may be tolerated if it succeeds but it is unforgivable if it fails. The interventional cardiologist sometimes feels like the handy man, told that he should not use the nearby shaky kitchen stool to change the light bulb but rather fetch the sturdy ladder from the basement. If he gets away with using the kitchen stool, he will be called “just lucky” and nobody will praise his courage and skill. If he falls, he will have to bear with the blame of having been stupid and stubborn on top of the broken arm. When will somebody turn up with the proof that carrying the bulky ladder up and down the basement stairs may be more dangerous than fixing the bulb on the kitchen stool? In a way, this is exactly what the paper on salvage angioplasty by Morrison et al. [7] in this issue does. It shows that the cumulated risks of the “safe” way may be worse than the apparently high risk of the “unsafe” way. The expansion of indications for angioplasty proposed by these authors may well be numerically negligible. Ideologically, it is of utmost importance. It is a “coming out” of coronary balloon angioplasty . Not infrequently, the angioplasty operator is confronted with a patient whose clinical problem resides on a single critical lesion. It is obvious that dilatation of this lesion will considerably improve the patient’s symptoms or even render him asymptomatic. But it is also obvious that an acute occlusion is likely to be fatal. The advent of
From the Cardiology, University Hospital, Bern, Switzerland.
Address reprint requests to, Bernhard Meier, MD, Professor and Head of Cardiology, University Hospital, 3010 Bern, Switzerland.
166
Editorial
percutaneous cardiopulmonary support [8] does not resolve the issue because of its short-lived protection and intrinsic complications (groin problems may induce coronary occlusion after removal of the support system). If the lesion in question is a complex and long left main stem stenosis, the risk of angioplasty is clearly worse than that of bypass surgery and the latter has to be advocated. If the problem is a short and concentric stenosis in a large left main stem, the risk of an acute and irreversible occlusion after angioplasty is probably less than 5%. Even if such a complication is a priori considered fatal, the risk of mortality is comparable to that of elective bypass surgery for left main stem disease. We are not ready yet to take on this kind of patient for angioplasty, yet we probably should. If the patient has a single culprit lesion, a poor left ventricular function, and is in generally poor health, the projected risk of bypass surgery may amount to more than 20% as indicated for the cases of Morrison et al. [7]. Dilating his short and concentric culprit lesion should have a clearly lower risk of mortality, even if the lesion is in a so-called last remaining vessel. Morrison et al. are telling us that these patients and perhaps even those with less ideal and up to 3 lesions should be accepted for angioplasty and that it may even be unethical not to do so. Are they seeing things too optimistically? First, their prospective estimates of surgical mortality may be found exaggerated by many a surgeon. On the one hand, the estimates are based on figures derived from actual and recent cases [9]. On the other hand, what is commonly referred to as “VA bashing” may discard the results of these cases as being too far from the gold standard to be seriously considered. The truth is that the vast majority of bypass operations (and angioplasty procedures for that matter) are performed in centers much more comparable with those used as a reference than with the super-specialized high-class institutions claiming superior results. Second, the relatively short follow-up tends to underestimate serious angioplasty complications. They may well be limited to the immediate phase after the intervention. The high recurrence rate, however, frequently imposes reinterventions with a new, definite risk of serious complications and mortality. The fact that the surgical series used as a reference only include the 30 day mortality is not an excuse. Surgery has a much lower rate of reinterventions. Third, the 2 patients dilated for acute myocardial infarction stray from the rest of the cohort. It is generally accepted and even recommended to attempt angioplasty on occluded vessels visualized early during an acute infarction, even if the risk of elective angioplasty of the same vessel would have been deemed excessive while it was still patent. The lesson we learn from the brave and pioneering
efforts of Morrison et al. [7] is that angioplasty is about to come out of hiding in the shadow of bypass surgery. No longer is it merely an acceptable technique for cases that are not sick enough to merit surgery and very easy cases for surgery. Suddenly, it claims to be the better solution for a small but worrisome group of patients in dire need of revascularization. Yes, angioplasty does carry considerable mortality in this group but it offers better odds than either surgery or medical treatment. The notion of being the new ultimate provider, rather than someone who more or less illicitly snatches the patient away from the conventional ultimate provider, is bound to be a psychological incentive for the interventional cardiologist grappling to cope with a mortality rate so far unknown except with high-risk surgery. It is important to state that unstable angina is not necessarily a prerequisite for angioplasty in such patients but angina refractary to therapy is. Of the new devices, only the stent is of real help, since it is of significant benefit in dealing with the problem of acute occlusion, the single largest worry with these kinds of patients. The “coming out” of coronary balloon angioplasty has long been overdue. The paper of Morrison et al. may not accomplish this process but it may well be the igniting spark.
REFERENCES I . Griintzig A: Transluminal dilatation of coronary artery stenosis. Lancet 1:263, 1978. 2 . Pande AK, Meier B, Rutishauser W: Implications of coronary angiography in patients with suspected or known coronary artery disease. Int J Cardiol (in press). 3. Meier B: Indications of coronary angioplasty and bypass surgery. Schweiz Med Wschr (in press). 4. Topol El, Ellis SG, Bates ER, Muller DWM, Schork N, Schork MA: Analysis of coronary angioplasty practice in the United States using a private insurance database. J Am Coll Cardiol 19:13A, 1992 (abstract). 5 . Parisi AF, Folland ED,Hartigan P, on behalf of the Veteran Affairs ACME Investigators: A comparison of angioplasty with medical therapy in the treatment of single-vessel coronary artery disease. N Engl J Med 326:lO-16, 1992. 6. Meier B, Urban P, Dorsaz PA, Favre J: Surgical standby for balloon angioplasty. JAMA 268:741-745, 1992. 7. Morrison DA, Barbiere CC, Johnson R , Marshall G , Fullerton G , Hammermeister KE, Grover FL, Morgan P, Olsen MA, Stovall JR, West E, Wolf D: Slavage angioplasty: an alternative to high risk surgery for unstable angina. Cathet Cardiovasc Diagn 27:169178, 1992. 8. Shawl FA, Doumaski MJ, Punja S, Hernandez DJ: Percutaneous cardipulmonary bypass support in high-risk patients undergoing percutaneous transluminal coronary angioplasty. Am J Cardiol 64: 1258-1 263, 1989. 9. Grover FL, Hammermeister KE, Burchfiel C, and the VA Surgeons: Initial report of the Veterans Administration Preoperative Risk Factor Assessment Study for Cardiac Surgery. Ann Thorac Surg 50:12-28, 1991.
