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Experience with Intraaortic Balloon Counterpulsation
Experience with Intraaortic Balloon Counterpulsation Peter M. Sanfelippo, M.D., Norman H. Baker, M.D., H. Gene Ewy, M.D., Patrick J. Moore, M.D., John W. Thomas, M.D., George J. Brahos, M.D., and Robert F. McVicker, M.D. ABSTRACT An eleven-year experience with intraaortic balloon pumping (IABP) or counterpulsation in 637 patients was analyzed with respect to early and late results. Intraaortic balloon pumping was employed for left ventricular pump failure, for coronary insufficiency, and in association with cardiac operations. Late results were analyzed by follow-up of 283 (93%)of the 304 patients leaving the hospital, and were studied with respect to duration of survival, activity status, occupational status, presence of cardiac symptoms, use of cardiac medications, and presence of lower extremity claudication. Early results were analyzed for hospital survival (304/637 [48%1). Patient complications of IABP included wound infection (11637 or 0.2%), vascular complications (66/637 or 10.4%), and balloon failure (8/637 or 1.3%).No deaths were attributable to complications of IABP. Survival did not correlate with the duration of IABP. Survival was improved in patients who had revascularization in association with IABP. The failing heart, whether impaired on a chronic or acute basis, often can be improved by a period of assistance. Of the methods that have been studied to provide assistance to the failing heart, only intraaortic balloon pumping (IABP) or counterpulsation has found a place in the clinical practice. Because of the capability of IABP to reduce left ventricular energy expenditure and maximize coronary perfusion, the failing heart can be helped. The types of clinical situations in which IABP can be of benefit are as follows: left ventricular pump failure, usually secondary to acute myocardial infarction; coronary insufficiency, usually with extending infarction or unstable angina; and before and after cardiopulmonary bypass (open-heart operation), usually for unstable anatomy or function or both. Our experience with IABP in these situations is presented to define its clinical safety and usefulness.
Material and Method This experience included five community hospitals and reviewed the first eleven years (1973 through 1984) of IABP in our practice. The Datascope System was employed. In most of the patients, the balloon catheter was passed through a graft on the common femoral artery. From the Ohio Heart and Thoracic Surgery Center, Columbus, OH. Presented at the Twenty-first Annual Meeting of The Society of Thoracic Surgeons, Phoenix, AZ, Jan 21-23, 1985. Address reprint requests to Dr. Sanfelippo, Ohio Heart and Thoracic Surgery Center, 931 Chatham Lane, Columbus, OH 43221.
36
Recently, the percutaneous approach using the common femoral artery has been employed. Occasionally, the abdominal aorta and thoracic aorta have served as the insertion sites. While the balloon is in place, the patient is maintained on a drip of low molecular weight dextran or heparin or both. If thrombus is noted on the catheter at its removal, proximal and distal thrombectomies are carried out. Attempts were made to contact all hospital survivors. Follow-up inteviews concerned activity, work status, presence of angina, presence of congestive heart failure, presence of claudication, and medications. Follow-up data were obtained on 283 (93%) of the 304 hospital survivors. Statistical significance was determined by the 2 x 2 chi-square test.
Results During the eleven-year period, 637 patients were identified as candidates for IABP. Most of the patients were men (463 or 73%), and the mean age of the patients was 58 years (range, 23 to 82 years). The indications for IABP were left ventricular pump failure (228 patients), coronary insufficiency (134), and association with an open-heart procedure (275). Hospital survival by indication was as follows: 32% (73/228) for patients with left ventricular pump failure; 66% (89/134) for patients with coronary insufficiency; and 52% (142/275)for patients with a n associated cardiac operation. Overall survival was 48%. When patients with left ventricular pump failure as the indication for IABP underwent the appropriate cardiac operation-coronary revascularization, correction of mitral insufficiency, or repair of a ventricular aneurysm-survival was improved. Twenty of the 228 patients in this category had such a n operation, and ll or 55% survived. Without an operation, only 62 or 35% of 208 patients survived. This increase in survival was statistically significant at the 0.05 level. When coronary insufficiency was the indication for IABP, 24 patients had coronary revascularization in addition to IABP. Survival was 75% (18 patients). Without the operation, survival was 65% (7UllO). This differences was not statistically significant. When the group of patients receiving IABP before or after cardiopulmonary bypass was analyzed, several observations were made. The major indication for IABP was cardiac failure after bypass, which accounted for 210 (76%) of the 275 patients in this group. That indication was associated with a 44% survival (92 patients). The indications before cardiopulmonary bypass were left main anatomy (now rarely an indication for IABP) and
37 Sanfelippo et al: lntraaortic Balloon Counterpulsation
Table I. Complications by Indication for Balloon Counterpulsationa Complications Indication LV pump failure Coronary insufficiency
Open-heart operation Total
No. of
Failure to Insert
Wound
Vascular
Patients
Problem
Balloon
228 134 275
18 7 16
1 0 0
32 15 19
3 2 3
637
41 (6.4)
1 (0.15)
66 (10.4)
8 (1.3)
Infection
"Numbers in parentheses are percents.
LV
=
left ventricular.
poor left ventricular function. The former had a 94% survival (31/33), which was statistically significant at the 0.001 level compared with survival for the latter indication. It had a 59% survival (19/32), which was not statistically significant. Intraaortic balloon counterpulsation in association with a cardiac procedure was used for 6% of the cardiac surgical patients in the first five years but only 4% in the last six years of the study. Survival in all groups was compared with the duration of IABP. No adverse effect on survival was noted with IABP of up to 14 days for any of the three groups. In the group with left ventricular pump failure, survival of patients having IABP for more than 15 days was 41%, which was not significantly different from the survival statistics for the group as a whole. The problems and complications encountered in these 637 patients were summarized by the indication for IABP (Table 1). In 41 (6.4%),successful IABP was precluded because of failure to insert the balloon catheter; this failure was due to peripheral vascular disease. Wound infection at the balloon catheter site occurred in 1 patient (0.2%). Problems with the balloon cathether necessitating removal or replacement were experienced in 8 patients (1.3%). Sixty-six patients (10.4%)had vascular insufficiency. Of the 228 patients with left ventricular pump failure as the indication for IABP, 32 (14.0%) experienced this complication compared with 15 (11.2%)of the 134 patients with coronary insufficiency and 19 (6.9%)of the 275 patients having an open-heart operation. The 14.0% incidence of vascular problems in the group with left ventricular pump failure was statistically significant at the 0.01 level. There was no significant variation in sex or age distribution for this group compared with the other two groups. Nor did this group have a higher incidence of patients requiring a longer duration of IABP. Female patients constituted 27% of all the patients in this study and 44% (29/66) of patients with vascular complications. Among all the patients with vascular problems, 2 male patients required amputations. The rate of vascular problems related to use of the percutaneous intraaortic balloon was 25.2% contrasted with 6.6% for the nonpercutaneously placed balloons.
This difference was significant at the 0.001 level. A decrease in the level of vascular complications, recently noted, may be due to the smaller sized balloon catheters and introducer sheaths. Follow-up was obtained on 283 of the 304 hospital survivors, a follow-up of 93%. Review of the duration of follow-up after IABP demonstrated that 181 (64%)of the patients survived three or more years following IABP. Of the 283 patients on whom follow-up data were available; 214 (76%)were alive at the time of the most recent follow-up. The diversity of these patients within the groupings by indication for IABP precludes meaningful comparisons of survivals of these patients. With respect to angina, 63% were free from angina (Table 2). With respect to evidence of congestive heart failure, 52%were free from such evidence, but 43% had mild failure (Table 3). The patients' subjective assessment of their activity status revealed that 56% considered themselves to have a normal activity level, 36% considered themselves limited to moderate activity, and 7% considered themselves very limited (Table 4). With respect to occupational status, 38% of the patients remained active at the occupation they had before IABP, 24% were disabled with respect to their previous occupation, and 36% were retired (Table 5). As for the incidence of symptoms of claudication in the limb that hosted the intraaortic balloon, 29% had such symptoms (Table 6). Of surviving patients who had vascular complications of IABP, 10 of 21 or 47.6% had claudication.
Comment Over the years, many attempts have been made to assist the failing heart. These attempts can be categorized as those employing total or partial cardiac bypass, those providing rhythmic cardiac compression, and those employing diastolic augmentation. Diastolic augmentation using an intraaortic balloon has found the most clinical application. Although Moulopoulos and associates [ 11 reported on the concept and technique of intraaortic balloon counterpulsation, the technique was applied clinically by Kantrowitz and co-workers (21. The experience of Dunkman and colleagues [3] with patients with car-
38 The Annals of Thoracic Surgery Vol 41 No 1 January 1986
Table 2. Follow-up with Reference to Angina” Angina Status lndica tion
No. of Patients
None, N o Medication
None, on Medication
LV p u m p failure Coronary insufficiency Open-heart operation
38 47 129
16 (42%) 13 (28) 45 (35)
8 (21) 12 (25.5) 41 (32)
214
74 (35)
61 (28.5)
Total
Mild
Severe
13 (34) 18 (38)
1 (3) 4 (8.5)
41 (32)
2 (1)
72 (34)
7 (3)
Mild
Severe
15 (39)
“Numbers in parentheses are percents
LV
=
left ventricular.
Table 3 . Follow-up with Reference to Congestive Heart Failure” Congestive Heart Failure Indication
No. of Patients
None, No Medication
None, on Medication
LV p u m p failure Coronary insufficiency Open-heart operation
38 47 129
7 (18) 6 (13) 19 (15)
15 (39) 18 (38) 47 (36)
60 (46.5)
1 (3) 5 (11) 3 (2)
214
32 (15)
80 (3)
93 (43)
9 (4)
Total
18 (38)
“Numbers in parentheses are percents.
LV = left ventricular.
Table 4 . Follow-up with Reference to Subjective Assessment of Activity“ Subjective Activity Status ~~~
Indication
No. of Patients
Unlimited
All but Strenuous
Moderate
Sedentary
LV pump failure Coronary insufficiency Open-heart operation Total
38 47 129 214
11 (29) 14 (30) 50 (39) 75 (35)
12 (31.5) 10 (21) 23 (18) 45 (21)
12 (31.5) 18 (38) 48 (37) 78 (36)
3 (8) 5 (11) 8 (6) 16 (7.5)
‘Numbers in parentheses are percents LV = left ventricular.
Table 5 . Follow-up with Reference to Occupation”
lndica tion
No. of Patients
LV pump failure Coronary insufficiency Open-heart operation Total
WorkinglHM
Retired
Unemployed
38 47 129
815 (34) 1512 (36) 429 (39.5)
12 (31.5) 8 (17) 32 (25)
12 (31.5) 21 (45) 43 (33)
1 (2) 1 (2) 3 (2)
214
81 (38)
52 (24)
76 (35.5)
5 (2)
Numbers in parentheses are percents.
HM
=
homemaker; LV
=
Occupational Status Disabled
left ventricular.
39 Sanfelippo et al: Intraaortic Balloon Counterpulsation
Table 6 . Follow-up zuith Reference to Claudication" No. of
Claudication Status
Indication
Patients
Present
LVPF
38 47 129
9 (24) 19 (40) 35 (27)
29 (76) 28 (60) 94 (73)
214
63 (29)
151 (71)
CI
OHS Total
Absent
"Numbers in parentheses are percents.
diogenic shock established a role for IABP in the treatm e n t of left ventricular p u m p failure. M u n d t h a n d coworkers [4] reported on a role for IABP in patients requiring emergent coronary revascularization for extending infarction, a n d Bolooki a n d associates (51 reviewed their experience with IABP in patients undergoing cardiac operations. They presented criteria for use of intraaortic balloon counterpulsation for failure after cardiopulmonary bypass. They also presented criteria for its use before failure in patients with anatomical or functional conditions associated with a high incidence of failure after left ventricular pumping. The physiological benefits of IABP include the following: decreased systolic aortic pressure (afterload); decreased myocardial oxygen consumption; increased diastolic aortic pressure (and therefore the diastolic gradient for coronary perfusion); increased stroke volu m e index a n d cardiac index; decreased mean capillary wedge pressure; and decreased total pulmonary vascular resistance [6]. In summary, these physiological effects, while decreasing myocardial oxygen demands, tend to increase myocardial oxygen supply. They further effect a n increase in external cardiac performance. All invasive procedures are associated with certain risks to t h e patient. This is equally true for IABP. The majority of complications relating to IABP involve the arterial tree (71. The reported incidence of vascular complications ranged from 8 to 18% (8-12). In the present series, the overall rate of vascular complications w a s 10.4%. T h e rate w a s higher a m o n g patients with percutaneous placement; in female patients, none of the vascular complications in this series were associated with death. T w o patients lost limbs because of vascular problems. The use of angiography to evaluate the iliac a n d femoral vessels in patients who are candidates for IABP h a s been suggested [13]. This has been employed infrequently a n d only in selected instances where history a n d examination suggested severe iliac or femoral artery disease o r both. The problem of intraaortic balloon insertion in vessels of small caliber h a s decreased a s a result of developments in the catheters. These developments are the result of the efforts of Bregman a n d Casarella [ 141 to apply percutaneous insertion techniques to intraaortic balloon placement. Survival h a s been reported to be improved with early, rather than late, application in patients needing IABP [5, 91. T h e survival of patients with preoperative IABP in
this series would support that concept. This study also supports the concept that when a cardiac operation is indicated, t h e combination of operative intervention a n d IABP resulted in improved survival. Hospital survival in this series w a s not adversely influenced by the duration of IABP. Follow-up studies [9] of patients with IABP in association with revascularization have suggested courses similar to those of patients not requiring IABP. The present study demonstrates that although the late survival of these patients would appear acceptable, the patient's survival and quality of life are a function of the residual cardiac disease.
References 1. Moulopoulos SD, Topaz SR, Kolff WJ: Diastolic balloon 2. 3. 4.
5.
6. 7.
8.
pumping (with carbon diozide) in aorta: mechanical assistance to failing circulation. Am Heart J 63:669, 1962 Kantrowitz A, Tjonneland S, Freed PS, et al: Initial clinical experience with intra-aortic balloon pumping in cardiogenic shock. JAMA 203:113, 1968 Dunkman WB, Leinbach RC, Buckley MJ, et al: Clinical and hemodynamic results of intra-aortic balloon pumping and surgery for cardiogenic shock. Circulation 46:465, 1972 Mundth ED, Buckley MJ, Gold HK, et al: lntraaortic balloon pumping and emergency coronary arterial revascularization for acute myocardial infarction with impending extension. Ann Thorac Surg 16:435, 1973 Bolooki H, Williams W, Thurer RJ, et al: Clinical and hemodynamic criteria for use of the intra-aortic balloon pump in patients requiring cardiac surgery. J Thorac Cardiovasc Surg 72:756, 1976 Igo SR, Hibbs CW, Trono R, et al: Intra-aortic balloon pumping: theory and practice. Artif Organs 2:249, 1978 h e r JM, Cohen SR, Virmani R, et al: Complications of the intraaortic balloon counterpulsation device: clinical and morphologic observations in 45 necropsy patients. Am J Cardiol 45:260, 1980 Singh JB, Connelly P, Kocot S, et al: Intra-aortic balloon counterpulsation in a community hospital. Chest 79:58,
1981 9. Golding LAR, Loop FD, Peter M, et al: Late survival following use of intraaortic balloon pump in revascularization operations. Ann Thorac Surg 30:48, 1980 10. Beckman CB, Geha AS, Hammond GL, et al: Results and
complications of intraaortic ballpon counterpulsation. Ann Thorac Surg 24:550, 1977 11. Alpert J, Parsonnet V, Goldenkranz RJ, et al: Limb ischemia during intraaortic balloon pumping: indication for femoralfemoral crossover graft. J Thorac Cardiovasc Surg 79:729,
1980 12. McCabe JC, Abel RM, Subramanian VA, et al: Complica-
tions of intraaortic balloon insertion and counterpulsation. Circulation 57:769, 1978 13. Bahn CH, Vitikainen KJ, Anderson CL, Whitney RB: Vascular evaluation for balloon pumping. Ann Thorac Surg
27:474, 1979 14. Bregman D, Casarella WJ: Percutaneous intraaortic balloon
pumping: initial clinical experience. Ann Thorac Surg
29:153, 1980
Discussion DR. HOOSHANC BOLOOKI (Miami, FL): I thank the authors for supplying me a copy of their manuscript. We have just heard a
40
The Annals of Thoracic Surgery Vol 41 No 1 January 1986
very nice presentation of long-term results in a large number of patients who were critically ill and were in need of intraaortic balloon pump support. The manuscript has a large amount of data, and I suggest that everyone read it. The authors indicate that recently their incidence of IABP has increased; this has been our experience also. I do not think the increase is due to a change in their policy, but rather it is because they are operating on very ill patients. Of the three ways that the intraaortic balloon pump is used in the course of cardiac operations, the authors have indicated their criteria for the first two groups of patients, that is, for elective and emergency use. A third group, that is, balloon standby, is under study at present. In these patients, we connect the electrocardiographic leads and the blood pressure line to the balloon pump console but the equipment is not used unless severe left ventricular failure develops either in the course of induction or postoperatively. I believe we save some ten to fifteen minutes by using the balloon assist early at the end of the operation instead of late after the operation is completed and the patient is unable to maintain spontaneous cardiac function. I ask the authors if, at any time, they have used the balloon pump on a standby basis instead of waiting until hemodynamic deterioration occurs. I emphasize that we are no longer using the intraaortic balloon pump for the anatomical reasons that we advocated in 1976. At present, we employ the balloon pump only if left ventricular failure occurs. In patients who receive diastolic augmentation during weaning from bypass, we believe balloon pumping is producing what we call mechanical preservation of the heart, which supplements the chemical preservation in the course of the operation. Opposed to these advantages, complications of IABP may be serious and could result in massive neurological problems or death. These types of complications were found in 0.8% of 3,400 patients whose cases I reviewed (Bolooki H: Clinical Application of Intra-Aortic Balloon Pump. Second edition. Mt. Kisco, NY, Futura, 1984). In two recent series (one from Shahian, one from Pennington), the incidence of vascular complications was 9.4%; in this series presented today, 10.4%. Dr. Sanfelippo did not indicate the incidence of aortic dissection with balloon catheter insertion. This condition is very difficult to recognize clinically, and may be present without one's knowledge. As a result, I suggest that if there is an intraaortic balloon cathether in one femoral artery, the opposite femoral artery should not be used for insertion of the inflow line from the heart-lung machine. Instead, the ascending aorta should serve for pump inflow because a dissection could be in progress after placement of the balloon catheter. At autopsy studies of patients who died after balloon pumping, 1 of every 5 patients had aortic dissection. The incidence of this complication is higher with percutaneous balloon catheters than surgical catheters. Like all medical devices, the intraaortic balloon pump is not safe at all times. Its complications have resulted in a number of litigations. We should thank the authors for bringing to our attention the long-term follow-up in a group of patients in whom this device was used. They defined their criteria very carefully, and their results are admirable. DR. JACK J . CURTIS (Columbia, MO): I congratulate the authors for showing once again that counterpulsation as accomplished by the intraaortic balloon pump not only can save lives, but that meaningful survival with a reasonable quality of life can be obtained.
During the last seven years, my colleagues and 1 have had experience with intraaortic balloon counterpulsation in more than 200 patients at the University of Missouri Hospital and Clinics. During this time there has been a major trend, as the authors said, toward use of the "quick and easy" percutaneous equipment. While both the surgical balloon and the percutaneous balloon seem to be effective in accomplishing diastolic pressure augmentation, we have believed that the surgical balloons are more effective in afterload reduction. And indeed we have had a couple of anecdotal instances in which patients could not be separated from cardiopulmonary bypass with a percutaneous balloon but required a surgical balloon. The larger diameter of the inflation-deflation tubing of the surgical balloon and the multiple sites for gas egress from within the surgical balloon, and therefore elimination of gas trapping, may be explanations for the superior afterload reduction that we see when the surgical balloon is used. I wonder if the authors have analyzed their survival data by type of equipment used. Do you have any evidence that rate of rise of left ventricular pressure varies in the same patient depending on the equipment employed? Is there a patient position that best takes advantage of intraaortic balloon counterpulsation? In other words, should our patients be placed in a reversed Trendelenburg position to more effectively take advantage of counterpulsation? DR. SHLOMO CABBAY (Newark, NJ): 1 congratulate Dr. Sanfelippo and his group for a very nice presentation and for reinforcing the belief in balloon counterpulsation about which many surgeons were very skeptical ten years ago. Balloon counterpulsation is obviously an acute intervention, and it is nice to see that many patients survive for a long time. Their prognosis, however, is dependent on the underlying disease. We probably have to concentrate more on a means of improving the short-term results. The reported survival of patients receiving counterpulsation has been about 50%. In this study, it is just less than 50%. 1 wonder if the authors think counterpulsation can ever improve survival to more than 50%. Second, we see more and more that patients respond more favorably to balloon counterpulsation following an open-heart operation than do patients with myocardial infarction. I wonder if the authors distinguish between these two groups and whether they see a difference in the result between postoperative use and use after myocardial infarction. Third, what is the average time for myocardial recovery after balloon counterpulsation-hours, days, or weeks? Last, in how many of the patients who did not survive was an attempt made to use other means of cardiac assistance? In summary, we know that balloon counterpulsation has some limiting factors that must be defined precisely to improve the results. The factors influencing how well the balloon will unload the heart and increase coronary perfusion must be understood well and enhanced. These include the position of the balloon, the volume, the aortic compliance, the diameter of the aorta, and the peripheral resistance. From studies that I have done using ascending balloon counterpulsation in dogs, the coronary perfusion can be increased over the 5 to 15% with the conventional balloon (30 cc) to 50 to 100%;with the ascending-descending intraaortic balloon, counterpulsation should be brought close to the coronary artery. I believe that an intensive study of the physiology of balloon counterpulsation should be undertaken to change the design completely and thus improve the overall results of counterpulsation.
41
Sanfelippo et al: Intraaortic Balloon Counterpulsation
DR. CECIL c. VAUGHN (Phoenix, AZ): I have a preliminary report on our modest experience with counterpulsation in 269 patients. The short-term mortality is 29%. Counterpulsation was used to wean 116 patients from cardiopulmonary bypass. In another 31 patients, the balloon was inserted in the acute care unit for treatment of left heart failure. This should have been done in the operating room, and my colleagues and 1 highly endorse the theory that delay in insertion of the balloon is a more critical determinant of survival than how long the balloon is used. The most common complication was leg ischemia, and 3 patients required amputation. We believe that use of the percutaneous balloon is less commonly associated with femoral artery injury. Successful left heart assist using the intraaortic balloon is limited as we become more aware of the importance of right heart failure. Have the authors used the balloon in the pulmonary artery, or what do they do to assist the failing right ventricle?
SANFELIPPO: I thank all the discussants, and I congratulate Dr. Vaughn on a superb series with a 71% survival. To answer Dr. Vaughn’s question, our experience with use of the intraaortic balloon pump for right-sided failure has been very limited and has met with little success. Relative to Dr. Gabbay’s comments, if a patient who has susDR.
tained a myocardial infarction has an indication for the balloon and unstable angina or evidence of extending infarction, then we believe the balloon is indicated; if the patient is suspected to have extension, then we think that catheterization and operation are indicated at the same interval we would normally use. We appreciate Dr. Curtis’s comments. Although we are surgeons, we do not have a strong belief that the surgical balloon is more effective. Dr. Curtis refers to data that suggest that the efficacy of the balloon relates to the ability of the balloon catheter to occupy and occlude the artery. The difference in volume between the sizes available for percutaneous insertion and surgical insertion is not very marked. We have not done any specific analysis of these data by size of balloon, nor have we had any experience attempting to use different positions to increase the efficacy of diastolic augmentation. Finally, 1 think we are all indebted to Dr. Bolooki for his efforts with the intraaortic balloon pump and his discussion of the complications that can occur. Like him, we believe that the balloon should not be left as a very last resort. Our policy in patients about whom we have concern but in whom we do not think there is a present indication for the balloon is to insert the percutaneous wire at the beginning of the operative procedure. If at any time during the procedure it becomes apparent that the patient needs the balloon catheter, it is then a simple matter to slide it in.
Material and Method This experience included five community hospitals and reviewed the first eleven years (1973 through 1984) of IABP in our practice. The Datascope System was employed. In most of the patients, the balloon catheter was passed through a graft on the common femoral artery. From the Ohio Heart and Thoracic Surgery Center, Columbus, OH. Presented at the Twenty-first Annual Meeting of The Society of Thoracic Surgeons, Phoenix, AZ, Jan 21-23, 1985. Address reprint requests to Dr. Sanfelippo, Ohio Heart and Thoracic Surgery Center, 931 Chatham Lane, Columbus, OH 43221.
36
Recently, the percutaneous approach using the common femoral artery has been employed. Occasionally, the abdominal aorta and thoracic aorta have served as the insertion sites. While the balloon is in place, the patient is maintained on a drip of low molecular weight dextran or heparin or both. If thrombus is noted on the catheter at its removal, proximal and distal thrombectomies are carried out. Attempts were made to contact all hospital survivors. Follow-up inteviews concerned activity, work status, presence of angina, presence of congestive heart failure, presence of claudication, and medications. Follow-up data were obtained on 283 (93%) of the 304 hospital survivors. Statistical significance was determined by the 2 x 2 chi-square test.
Results During the eleven-year period, 637 patients were identified as candidates for IABP. Most of the patients were men (463 or 73%), and the mean age of the patients was 58 years (range, 23 to 82 years). The indications for IABP were left ventricular pump failure (228 patients), coronary insufficiency (134), and association with an open-heart procedure (275). Hospital survival by indication was as follows: 32% (73/228) for patients with left ventricular pump failure; 66% (89/134) for patients with coronary insufficiency; and 52% (142/275)for patients with a n associated cardiac operation. Overall survival was 48%. When patients with left ventricular pump failure as the indication for IABP underwent the appropriate cardiac operation-coronary revascularization, correction of mitral insufficiency, or repair of a ventricular aneurysm-survival was improved. Twenty of the 228 patients in this category had such a n operation, and ll or 55% survived. Without an operation, only 62 or 35% of 208 patients survived. This increase in survival was statistically significant at the 0.05 level. When coronary insufficiency was the indication for IABP, 24 patients had coronary revascularization in addition to IABP. Survival was 75% (18 patients). Without the operation, survival was 65% (7UllO). This differences was not statistically significant. When the group of patients receiving IABP before or after cardiopulmonary bypass was analyzed, several observations were made. The major indication for IABP was cardiac failure after bypass, which accounted for 210 (76%) of the 275 patients in this group. That indication was associated with a 44% survival (92 patients). The indications before cardiopulmonary bypass were left main anatomy (now rarely an indication for IABP) and
37 Sanfelippo et al: lntraaortic Balloon Counterpulsation
Table I. Complications by Indication for Balloon Counterpulsationa Complications Indication LV pump failure Coronary insufficiency
Open-heart operation Total
No. of
Failure to Insert
Wound
Vascular
Patients
Problem
Balloon
228 134 275
18 7 16
1 0 0
32 15 19
3 2 3
637
41 (6.4)
1 (0.15)
66 (10.4)
8 (1.3)
Infection
"Numbers in parentheses are percents.
LV
=
left ventricular.
poor left ventricular function. The former had a 94% survival (31/33), which was statistically significant at the 0.001 level compared with survival for the latter indication. It had a 59% survival (19/32), which was not statistically significant. Intraaortic balloon counterpulsation in association with a cardiac procedure was used for 6% of the cardiac surgical patients in the first five years but only 4% in the last six years of the study. Survival in all groups was compared with the duration of IABP. No adverse effect on survival was noted with IABP of up to 14 days for any of the three groups. In the group with left ventricular pump failure, survival of patients having IABP for more than 15 days was 41%, which was not significantly different from the survival statistics for the group as a whole. The problems and complications encountered in these 637 patients were summarized by the indication for IABP (Table 1). In 41 (6.4%),successful IABP was precluded because of failure to insert the balloon catheter; this failure was due to peripheral vascular disease. Wound infection at the balloon catheter site occurred in 1 patient (0.2%). Problems with the balloon cathether necessitating removal or replacement were experienced in 8 patients (1.3%). Sixty-six patients (10.4%)had vascular insufficiency. Of the 228 patients with left ventricular pump failure as the indication for IABP, 32 (14.0%) experienced this complication compared with 15 (11.2%)of the 134 patients with coronary insufficiency and 19 (6.9%)of the 275 patients having an open-heart operation. The 14.0% incidence of vascular problems in the group with left ventricular pump failure was statistically significant at the 0.01 level. There was no significant variation in sex or age distribution for this group compared with the other two groups. Nor did this group have a higher incidence of patients requiring a longer duration of IABP. Female patients constituted 27% of all the patients in this study and 44% (29/66) of patients with vascular complications. Among all the patients with vascular problems, 2 male patients required amputations. The rate of vascular problems related to use of the percutaneous intraaortic balloon was 25.2% contrasted with 6.6% for the nonpercutaneously placed balloons.
This difference was significant at the 0.001 level. A decrease in the level of vascular complications, recently noted, may be due to the smaller sized balloon catheters and introducer sheaths. Follow-up was obtained on 283 of the 304 hospital survivors, a follow-up of 93%. Review of the duration of follow-up after IABP demonstrated that 181 (64%)of the patients survived three or more years following IABP. Of the 283 patients on whom follow-up data were available; 214 (76%)were alive at the time of the most recent follow-up. The diversity of these patients within the groupings by indication for IABP precludes meaningful comparisons of survivals of these patients. With respect to angina, 63% were free from angina (Table 2). With respect to evidence of congestive heart failure, 52%were free from such evidence, but 43% had mild failure (Table 3). The patients' subjective assessment of their activity status revealed that 56% considered themselves to have a normal activity level, 36% considered themselves limited to moderate activity, and 7% considered themselves very limited (Table 4). With respect to occupational status, 38% of the patients remained active at the occupation they had before IABP, 24% were disabled with respect to their previous occupation, and 36% were retired (Table 5). As for the incidence of symptoms of claudication in the limb that hosted the intraaortic balloon, 29% had such symptoms (Table 6). Of surviving patients who had vascular complications of IABP, 10 of 21 or 47.6% had claudication.
Comment Over the years, many attempts have been made to assist the failing heart. These attempts can be categorized as those employing total or partial cardiac bypass, those providing rhythmic cardiac compression, and those employing diastolic augmentation. Diastolic augmentation using an intraaortic balloon has found the most clinical application. Although Moulopoulos and associates [ 11 reported on the concept and technique of intraaortic balloon counterpulsation, the technique was applied clinically by Kantrowitz and co-workers (21. The experience of Dunkman and colleagues [3] with patients with car-
38 The Annals of Thoracic Surgery Vol 41 No 1 January 1986
Table 2. Follow-up with Reference to Angina” Angina Status lndica tion
No. of Patients
None, N o Medication
None, on Medication
LV p u m p failure Coronary insufficiency Open-heart operation
38 47 129
16 (42%) 13 (28) 45 (35)
8 (21) 12 (25.5) 41 (32)
214
74 (35)
61 (28.5)
Total
Mild
Severe
13 (34) 18 (38)
1 (3) 4 (8.5)
41 (32)
2 (1)
72 (34)
7 (3)
Mild
Severe
15 (39)
“Numbers in parentheses are percents
LV
=
left ventricular.
Table 3 . Follow-up with Reference to Congestive Heart Failure” Congestive Heart Failure Indication
No. of Patients
None, No Medication
None, on Medication
LV p u m p failure Coronary insufficiency Open-heart operation
38 47 129
7 (18) 6 (13) 19 (15)
15 (39) 18 (38) 47 (36)
60 (46.5)
1 (3) 5 (11) 3 (2)
214
32 (15)
80 (3)
93 (43)
9 (4)
Total
18 (38)
“Numbers in parentheses are percents.
LV = left ventricular.
Table 4 . Follow-up with Reference to Subjective Assessment of Activity“ Subjective Activity Status ~~~
Indication
No. of Patients
Unlimited
All but Strenuous
Moderate
Sedentary
LV pump failure Coronary insufficiency Open-heart operation Total
38 47 129 214
11 (29) 14 (30) 50 (39) 75 (35)
12 (31.5) 10 (21) 23 (18) 45 (21)
12 (31.5) 18 (38) 48 (37) 78 (36)
3 (8) 5 (11) 8 (6) 16 (7.5)
‘Numbers in parentheses are percents LV = left ventricular.
Table 5 . Follow-up with Reference to Occupation”
lndica tion
No. of Patients
LV pump failure Coronary insufficiency Open-heart operation Total
WorkinglHM
Retired
Unemployed
38 47 129
815 (34) 1512 (36) 429 (39.5)
12 (31.5) 8 (17) 32 (25)
12 (31.5) 21 (45) 43 (33)
1 (2) 1 (2) 3 (2)
214
81 (38)
52 (24)
76 (35.5)
5 (2)
Numbers in parentheses are percents.
HM
=
homemaker; LV
=
Occupational Status Disabled
left ventricular.
39 Sanfelippo et al: Intraaortic Balloon Counterpulsation
Table 6 . Follow-up zuith Reference to Claudication" No. of
Claudication Status
Indication
Patients
Present
LVPF
38 47 129
9 (24) 19 (40) 35 (27)
29 (76) 28 (60) 94 (73)
214
63 (29)
151 (71)
CI
OHS Total
Absent
"Numbers in parentheses are percents.
diogenic shock established a role for IABP in the treatm e n t of left ventricular p u m p failure. M u n d t h a n d coworkers [4] reported on a role for IABP in patients requiring emergent coronary revascularization for extending infarction, a n d Bolooki a n d associates (51 reviewed their experience with IABP in patients undergoing cardiac operations. They presented criteria for use of intraaortic balloon counterpulsation for failure after cardiopulmonary bypass. They also presented criteria for its use before failure in patients with anatomical or functional conditions associated with a high incidence of failure after left ventricular pumping. The physiological benefits of IABP include the following: decreased systolic aortic pressure (afterload); decreased myocardial oxygen consumption; increased diastolic aortic pressure (and therefore the diastolic gradient for coronary perfusion); increased stroke volu m e index a n d cardiac index; decreased mean capillary wedge pressure; and decreased total pulmonary vascular resistance [6]. In summary, these physiological effects, while decreasing myocardial oxygen demands, tend to increase myocardial oxygen supply. They further effect a n increase in external cardiac performance. All invasive procedures are associated with certain risks to t h e patient. This is equally true for IABP. The majority of complications relating to IABP involve the arterial tree (71. The reported incidence of vascular complications ranged from 8 to 18% (8-12). In the present series, the overall rate of vascular complications w a s 10.4%. T h e rate w a s higher a m o n g patients with percutaneous placement; in female patients, none of the vascular complications in this series were associated with death. T w o patients lost limbs because of vascular problems. The use of angiography to evaluate the iliac a n d femoral vessels in patients who are candidates for IABP h a s been suggested [13]. This has been employed infrequently a n d only in selected instances where history a n d examination suggested severe iliac or femoral artery disease o r both. The problem of intraaortic balloon insertion in vessels of small caliber h a s decreased a s a result of developments in the catheters. These developments are the result of the efforts of Bregman a n d Casarella [ 141 to apply percutaneous insertion techniques to intraaortic balloon placement. Survival h a s been reported to be improved with early, rather than late, application in patients needing IABP [5, 91. T h e survival of patients with preoperative IABP in
this series would support that concept. This study also supports the concept that when a cardiac operation is indicated, t h e combination of operative intervention a n d IABP resulted in improved survival. Hospital survival in this series w a s not adversely influenced by the duration of IABP. Follow-up studies [9] of patients with IABP in association with revascularization have suggested courses similar to those of patients not requiring IABP. The present study demonstrates that although the late survival of these patients would appear acceptable, the patient's survival and quality of life are a function of the residual cardiac disease.
References 1. Moulopoulos SD, Topaz SR, Kolff WJ: Diastolic balloon 2. 3. 4.
5.
6. 7.
8.
pumping (with carbon diozide) in aorta: mechanical assistance to failing circulation. Am Heart J 63:669, 1962 Kantrowitz A, Tjonneland S, Freed PS, et al: Initial clinical experience with intra-aortic balloon pumping in cardiogenic shock. JAMA 203:113, 1968 Dunkman WB, Leinbach RC, Buckley MJ, et al: Clinical and hemodynamic results of intra-aortic balloon pumping and surgery for cardiogenic shock. Circulation 46:465, 1972 Mundth ED, Buckley MJ, Gold HK, et al: lntraaortic balloon pumping and emergency coronary arterial revascularization for acute myocardial infarction with impending extension. Ann Thorac Surg 16:435, 1973 Bolooki H, Williams W, Thurer RJ, et al: Clinical and hemodynamic criteria for use of the intra-aortic balloon pump in patients requiring cardiac surgery. J Thorac Cardiovasc Surg 72:756, 1976 Igo SR, Hibbs CW, Trono R, et al: Intra-aortic balloon pumping: theory and practice. Artif Organs 2:249, 1978 h e r JM, Cohen SR, Virmani R, et al: Complications of the intraaortic balloon counterpulsation device: clinical and morphologic observations in 45 necropsy patients. Am J Cardiol 45:260, 1980 Singh JB, Connelly P, Kocot S, et al: Intra-aortic balloon counterpulsation in a community hospital. Chest 79:58,
1981 9. Golding LAR, Loop FD, Peter M, et al: Late survival following use of intraaortic balloon pump in revascularization operations. Ann Thorac Surg 30:48, 1980 10. Beckman CB, Geha AS, Hammond GL, et al: Results and
complications of intraaortic ballpon counterpulsation. Ann Thorac Surg 24:550, 1977 11. Alpert J, Parsonnet V, Goldenkranz RJ, et al: Limb ischemia during intraaortic balloon pumping: indication for femoralfemoral crossover graft. J Thorac Cardiovasc Surg 79:729,
1980 12. McCabe JC, Abel RM, Subramanian VA, et al: Complica-
tions of intraaortic balloon insertion and counterpulsation. Circulation 57:769, 1978 13. Bahn CH, Vitikainen KJ, Anderson CL, Whitney RB: Vascular evaluation for balloon pumping. Ann Thorac Surg
27:474, 1979 14. Bregman D, Casarella WJ: Percutaneous intraaortic balloon
pumping: initial clinical experience. Ann Thorac Surg
29:153, 1980
Discussion DR. HOOSHANC BOLOOKI (Miami, FL): I thank the authors for supplying me a copy of their manuscript. We have just heard a
40
The Annals of Thoracic Surgery Vol 41 No 1 January 1986
very nice presentation of long-term results in a large number of patients who were critically ill and were in need of intraaortic balloon pump support. The manuscript has a large amount of data, and I suggest that everyone read it. The authors indicate that recently their incidence of IABP has increased; this has been our experience also. I do not think the increase is due to a change in their policy, but rather it is because they are operating on very ill patients. Of the three ways that the intraaortic balloon pump is used in the course of cardiac operations, the authors have indicated their criteria for the first two groups of patients, that is, for elective and emergency use. A third group, that is, balloon standby, is under study at present. In these patients, we connect the electrocardiographic leads and the blood pressure line to the balloon pump console but the equipment is not used unless severe left ventricular failure develops either in the course of induction or postoperatively. I believe we save some ten to fifteen minutes by using the balloon assist early at the end of the operation instead of late after the operation is completed and the patient is unable to maintain spontaneous cardiac function. I ask the authors if, at any time, they have used the balloon pump on a standby basis instead of waiting until hemodynamic deterioration occurs. I emphasize that we are no longer using the intraaortic balloon pump for the anatomical reasons that we advocated in 1976. At present, we employ the balloon pump only if left ventricular failure occurs. In patients who receive diastolic augmentation during weaning from bypass, we believe balloon pumping is producing what we call mechanical preservation of the heart, which supplements the chemical preservation in the course of the operation. Opposed to these advantages, complications of IABP may be serious and could result in massive neurological problems or death. These types of complications were found in 0.8% of 3,400 patients whose cases I reviewed (Bolooki H: Clinical Application of Intra-Aortic Balloon Pump. Second edition. Mt. Kisco, NY, Futura, 1984). In two recent series (one from Shahian, one from Pennington), the incidence of vascular complications was 9.4%; in this series presented today, 10.4%. Dr. Sanfelippo did not indicate the incidence of aortic dissection with balloon catheter insertion. This condition is very difficult to recognize clinically, and may be present without one's knowledge. As a result, I suggest that if there is an intraaortic balloon cathether in one femoral artery, the opposite femoral artery should not be used for insertion of the inflow line from the heart-lung machine. Instead, the ascending aorta should serve for pump inflow because a dissection could be in progress after placement of the balloon catheter. At autopsy studies of patients who died after balloon pumping, 1 of every 5 patients had aortic dissection. The incidence of this complication is higher with percutaneous balloon catheters than surgical catheters. Like all medical devices, the intraaortic balloon pump is not safe at all times. Its complications have resulted in a number of litigations. We should thank the authors for bringing to our attention the long-term follow-up in a group of patients in whom this device was used. They defined their criteria very carefully, and their results are admirable. DR. JACK J . CURTIS (Columbia, MO): I congratulate the authors for showing once again that counterpulsation as accomplished by the intraaortic balloon pump not only can save lives, but that meaningful survival with a reasonable quality of life can be obtained.
During the last seven years, my colleagues and 1 have had experience with intraaortic balloon counterpulsation in more than 200 patients at the University of Missouri Hospital and Clinics. During this time there has been a major trend, as the authors said, toward use of the "quick and easy" percutaneous equipment. While both the surgical balloon and the percutaneous balloon seem to be effective in accomplishing diastolic pressure augmentation, we have believed that the surgical balloons are more effective in afterload reduction. And indeed we have had a couple of anecdotal instances in which patients could not be separated from cardiopulmonary bypass with a percutaneous balloon but required a surgical balloon. The larger diameter of the inflation-deflation tubing of the surgical balloon and the multiple sites for gas egress from within the surgical balloon, and therefore elimination of gas trapping, may be explanations for the superior afterload reduction that we see when the surgical balloon is used. I wonder if the authors have analyzed their survival data by type of equipment used. Do you have any evidence that rate of rise of left ventricular pressure varies in the same patient depending on the equipment employed? Is there a patient position that best takes advantage of intraaortic balloon counterpulsation? In other words, should our patients be placed in a reversed Trendelenburg position to more effectively take advantage of counterpulsation? DR. SHLOMO CABBAY (Newark, NJ): 1 congratulate Dr. Sanfelippo and his group for a very nice presentation and for reinforcing the belief in balloon counterpulsation about which many surgeons were very skeptical ten years ago. Balloon counterpulsation is obviously an acute intervention, and it is nice to see that many patients survive for a long time. Their prognosis, however, is dependent on the underlying disease. We probably have to concentrate more on a means of improving the short-term results. The reported survival of patients receiving counterpulsation has been about 50%. In this study, it is just less than 50%. 1 wonder if the authors think counterpulsation can ever improve survival to more than 50%. Second, we see more and more that patients respond more favorably to balloon counterpulsation following an open-heart operation than do patients with myocardial infarction. I wonder if the authors distinguish between these two groups and whether they see a difference in the result between postoperative use and use after myocardial infarction. Third, what is the average time for myocardial recovery after balloon counterpulsation-hours, days, or weeks? Last, in how many of the patients who did not survive was an attempt made to use other means of cardiac assistance? In summary, we know that balloon counterpulsation has some limiting factors that must be defined precisely to improve the results. The factors influencing how well the balloon will unload the heart and increase coronary perfusion must be understood well and enhanced. These include the position of the balloon, the volume, the aortic compliance, the diameter of the aorta, and the peripheral resistance. From studies that I have done using ascending balloon counterpulsation in dogs, the coronary perfusion can be increased over the 5 to 15% with the conventional balloon (30 cc) to 50 to 100%;with the ascending-descending intraaortic balloon, counterpulsation should be brought close to the coronary artery. I believe that an intensive study of the physiology of balloon counterpulsation should be undertaken to change the design completely and thus improve the overall results of counterpulsation.
41
Sanfelippo et al: Intraaortic Balloon Counterpulsation
DR. CECIL c. VAUGHN (Phoenix, AZ): I have a preliminary report on our modest experience with counterpulsation in 269 patients. The short-term mortality is 29%. Counterpulsation was used to wean 116 patients from cardiopulmonary bypass. In another 31 patients, the balloon was inserted in the acute care unit for treatment of left heart failure. This should have been done in the operating room, and my colleagues and 1 highly endorse the theory that delay in insertion of the balloon is a more critical determinant of survival than how long the balloon is used. The most common complication was leg ischemia, and 3 patients required amputation. We believe that use of the percutaneous balloon is less commonly associated with femoral artery injury. Successful left heart assist using the intraaortic balloon is limited as we become more aware of the importance of right heart failure. Have the authors used the balloon in the pulmonary artery, or what do they do to assist the failing right ventricle?
SANFELIPPO: I thank all the discussants, and I congratulate Dr. Vaughn on a superb series with a 71% survival. To answer Dr. Vaughn’s question, our experience with use of the intraaortic balloon pump for right-sided failure has been very limited and has met with little success. Relative to Dr. Gabbay’s comments, if a patient who has susDR.
tained a myocardial infarction has an indication for the balloon and unstable angina or evidence of extending infarction, then we believe the balloon is indicated; if the patient is suspected to have extension, then we think that catheterization and operation are indicated at the same interval we would normally use. We appreciate Dr. Curtis’s comments. Although we are surgeons, we do not have a strong belief that the surgical balloon is more effective. Dr. Curtis refers to data that suggest that the efficacy of the balloon relates to the ability of the balloon catheter to occupy and occlude the artery. The difference in volume between the sizes available for percutaneous insertion and surgical insertion is not very marked. We have not done any specific analysis of these data by size of balloon, nor have we had any experience attempting to use different positions to increase the efficacy of diastolic augmentation. Finally, 1 think we are all indebted to Dr. Bolooki for his efforts with the intraaortic balloon pump and his discussion of the complications that can occur. Like him, we believe that the balloon should not be left as a very last resort. Our policy in patients about whom we have concern but in whom we do not think there is a present indication for the balloon is to insert the percutaneous wire at the beginning of the operative procedure. If at any time during the procedure it becomes apparent that the patient needs the balloon catheter, it is then a simple matter to slide it in.