IABP for Cardiogenic Shock After AMI
August, 1979
Experimental and Clinical Studies on the Effect of Intra-Aortic Balloon Pumping for Cardiogenic Shock Following Acute Myocardial Infarction Masayoshi Okada, Takuo Shiozawa, Masashi Iizuka, Kunio Okuno, Chuan Chung Chen, Shozo Matsuda, Kozo Yoneda, Atsushi Yano, Masaru Kawai and Sakae Asada ABSTRACT The effect of intra-aortic balloon pumping (IABP) on cardiogenic shock following acute myocardial infarction was studied experimentally and clinically. Effects of IABP on hemodynamic and electrocardiographic changes were studied with cardiogenic shock which was produced by multiple ligation of the coronary artery in dogs. Consequently, the hemodynamics as well as the ECG could be improved by diastolic augmentation and systolic unloading during IABP. But, these favorable effects of IABP were not seen in dogs whose infarcted area involved more than 50% of the free wall of the left ventricle. These facts were seen clinically in three autopsied cases. IABP was also attempted in dogs with complications such as ventricular septal defect (VSD) and mitral regurgitation (MR) following acute myocardial infarction, and significant improvement w a s obtained by IABP. No effects of IABP were seen in these series, however, when the value of the pulmonary-to-systemic flow ratio was over 4.5 in the VSD group and the mean left atrial pressure was more than 30 mmHg i n the MR group. Clinically, IABP was employed in 16 patients with cardiogenic shock secondary to acute myocardial infarction. Six (37.5%)were weaned from IABP. It can be concluded that IABP is effective i n improving hernodynamics as well as the ECG.
INTRODUCTION With the development of the coronary care unit and use of the pacemaker, the number of rhythm deaths due to acute myocardial infarction has decreased remarkably, but cardiogenic shock following acute myocardial infarction (AMI) is still associated with a high mortality rate.’-5 To decrease the mortality rate in patients with cardiogenic shock, experiment a l a n d clinical studies on intra-aortic balloon pumping were p e r f ~ r m e d . ~ ~ ’ EXPERIMENTAL STUDIES The Effect of IABP on Cardiogenic Shock The effect of IABP on acute myocardial infarction with cardiogenic shock was observed in 94 dogs. The chest was opened in the fourth intercostal space under endotracheal anesthesia, a n d respiration was maintained with a respirator. A balloon catheter was inserted through the femoral artery and located at the thoracic descending aorta as its tip came out at the distal portion of the origin of the subclavian artery (Fig. 1). The effect of IABP on hemodynamic a n d electrocardiographic changes was studied in the dogs in which AM1 was produced by multiple ligations of the coronary arteries. Consequently, significant increases of 40% in aortic diastolic pressure, 30% in cardiac output and 30% in coronary blood flow were recorded during BP ImmHg)
acute myocardial infarction, cardiogenic shock, intra-aortic balloon pumping (IABP), ventricular septal defect, mitral regurgitation From the 2nd Department of Surgery, Kobe University School of Medicine, Kobe, Japan. Address for correspondence: Masayoshi Okada, M.D., 2nd Department of Surgery, hobe University School of Medicine, 650 Kobe, Ikuta-ku Kusunoki-cho 7. Japan.
SYSTOLE
This paper was presented, in part, at the VIII World Congress of Cardiology, September. 1978, Tokyo, Japan.
D1 ASTOLE
FIG. 1. Schematic illustration of IABP.
27 1
Vol. 3, No. 3
Artificial Organs Ao. d i r s t .
Ao. 5 y r t . P .
0 Ing.
Ao.
1
syst.
3 hrr
P.
0 Iig.
1
3 hrs
Ao. d i s s t . P.
a.
c. 0.
P.
1
Iig.
c. 0.
diastole. On the other hand, a decrease of 20% in left ventricular pressure and aortic systolic pressure, and a fall of 15%in left ventricular end-diastolic pressure were also observed during systole. From these findings, the effects of diastolic augmentation and systolic unloading by IABP were clearly recognized (Fig. 2a). However, these favorable effects of IABP were not obtained in dogs in which the infarcted area was greater than 50% of the free wall of the left ventricle (Fig. 2b). The Effect o f I A B P on P o s t i n f a r c t i o n Mechanical Complications The effect of IABP on dogs with induced ventricular septa1 defect and mitral regurgitation following acute myocardial infarction was studied. VSD was created by tearing of the ventricular septum through the right ventricle, and MR was created by rupture of the chorda tendineae of the mitral valve (Fig. 3). The hemodynamic changes after creation of VSD secondary to myocardial infarction were significant decreases of 29% in mean aortic pressure, 20% in left ventricular systolic pressure, 46% in cardiac output and 23% in maximum dp/dt. The authors observed an increase of 13%in right ventricular pressure a n d 11%in pulmonary pressure related to the size of VSD. IABP was soon initiated causing increases of 7% in mean aortic pressure a n d 13%in cardiac output, a n d decreases of 10% in right ventricular pressure, 7%in pulmonary pressure and 30% in the pulmonary-to-systemic flow ratio (QP/QS) (Fig. 4a). The hemodynamic changes after creation of MR were significant reductions of 35% i n mean aortic pressure, 36% in left ventricular pressure, 36% in cardiac output a n d 35% in maximum dp/dt, a remarkable rise of 300% in mean left atrial pressure and a n increase of 50% in wedge pressure of the pulmonary artery. Initiating IABP at this point caused increases of 9% in mean aortic pressure, 18%in cardiac output and 16% in maximum dp/dt, and decreases of 7% in left ventricular pressure, 13% in mean left atrial pressure a n d 9% in pulmonary wedge pressure (PAWP) (Fig. 4b). From these findings, it could be concluded that IABP is effective in improving hemodynamics for both VSD a n d MR following AMI, except i n dogs in which the QP/QS was over 4.5 a n d the mean pressure i n the left atrium was over 30 mmHg.’
3 hrs
b.
100
IABP
IABP
FIG.2. Hemodynamic effects of IABP. a) Infarcted area less than 50% of LV surface. b) Infarcted area more than 50% of LV surface.
bR ral Valve
CLINICAL S T U D I E S On the basis of the authors’ experimental studies, IABP was employed in 16 cases of cardiogenic shock secondary to AM1 (Table). The 16 patients
FIG.3. Schematic illustration of the creation of VSD and MR.
272
August, 1979
'1
Ao. P (mean)
a1
'1
Max dp/dt
81
IABP f o r Cardiogenic Shock After A M I *I co
L V P (syst.)
+I
RVP
a.
ranged in age from 28 to 72 years (mean: 56 years). There were 12 males and 4 females. The duration of IABP ranged from 2 to 106 hours (mean: 41 hours). Significant effects of IABP were observed in all but three cases, i n which extensive myocardial infarction w a s confirmed by electrocardiogram a n d enzyme changes. Six (37.5010) of 16 patients with cardiogenic shock due to AM1 could be weaned from IABP. Coronary arteriography was safely performed in seven patients during IABP i n which the angiographic findings suggested operative feasibility, and emergency operations (one A-C bypass, one mitral valve replacement and one VSD closure) were performed in three cases. Following are some comments on five cases: the first three with patients who recovered from cardiogenic shock with IABP; the last two involving patients whose general condition deteriorated in spite of IABP application. Emergency operations were performed in these latter two patients after coronary arteriography during IABP. Case 5 A 56-year-old man developed cardiogenic shock with complete A-V block six hours after the onset of AM1 in July, 1976. His condition was somewhat improved by the administration of isoproterenol, and a temporary transvenous pacemaker was installed and initiated soon after he was admitted to the clinic. Thereafter, improvements i n heart rate a n d blood pressure were observed and coronary angiography was continuously performed. Occlusions at the proximal portion of the right coronary artery a n d t h e distal portion of the circumflex artery were revealed in angiographic findings. Unfortunately, there were n o graftable vessels in these findings a n d no indication to operate. The patient developed cardiogenic shock 16 hours after admission. With the immediate use of IABP, disappearance of chest p a i n , a n increase of blood pressure and urine volume, a n d a decrease of central venous pressure were observed (Fig. 5). The patient, fortunately, recovered from cardiogenic shock with IABP after 74 hours. He is doing well two years later. Case 7 A 59-year-old m a n developed abrupt cardiogenic shock three days after the onset of AM1 in October, 1976. With initiation of IABP, disappearance of chest pain a n d hemodynamic improvements were observed, and he recovered fully within 39 hours (Fig. 6). Angiographic findings in this case revealed 90% stenosis a t the proximal portion of the left anterior descending artery (LAD). Case 12 A 57-year-old woman developed a shock state with complete A-V block four hours after the onset
PAP
FIG.4. Hemodynamic effects of IABP for mechanical complications following AMI. a) Effects for AM1 t VSD. b) Effects for AM1 t MR.
TABLE CLINICAL EXPERIENCES OF IABP FOR CARDIOGENIC SHOCK FOLLOWING ACUTE MYOCARDIAL INFARCTION
Age -
Case
ie x
-
Duration I IABP (hrs
lecoverec
rgiography
om Shoc
iring IABP
1
K
S
61
F
3
No
No
Z
I
T
58
F
4
NO
NO
Remarks Extensive MI
3
K
K
71
M
52
NO
Yes
4
B
S
56
M
9
NO
Yes
5
M K
56
M
74
Ye5
no
6
1
K
64
M
9
NO
Yes
Chordal rupture-MVR
7
K
T
59
M
39
Ye5
Yes
NCA 34%
8
Y
K
66
M
70
NO
No
Three vessel disease
9
N
M
72
M
10
No
No
Extensive MI
10 N T
52
M
63
Ye5
NO
11
N K
28
M
2
NO
No
N
57
F
59
Ye5
Yes
Complete A V block-pacing
I3 T K
67
F
106
N O
Yes
Emergency op i V S D c l o s ~ r e+ , n f a r c i e c i o m
Ye5
Yes
Complete A V block-pacing
NO
No
Extensive MI
No
Extensive MI A f - N S R
12 H
14
S
H
47
M
96
15
D T
44
M
4
16
F S
M 41 -
53
Yes -
Emergency I
op
A C bypa5i+mfarclectomy
Complete A V block-paclng
Emergency A C bypass
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Artificial Organs
-
-0zTent
3
.
rIsoproterenol. Nwadrenclllne
*
-Pacemaking
1 -ABP-
’
dn5m
mmHg
-1
IABP
IDO
50
,
-
8
?r
12
?‘
12
k
12
2i
12
k
12
i4
11
,’,
12
16
20
24
4
8
12
16
20
24
4
8
12
FIG.6. Clinical course during IABP (case 7).
FIG.5. Clinical course during IABP (case 5).
of myocardial infarction in June, 1977. Soon after admission to the clinic, a temporary transvenous pacemaker and IABP were simultaneously initiated. Significant effects of IABP were obtained and coronary angiography was continuously carried out during IABP. Angiographic findings suggested a hypoplastic right coronary artery and severe stenosis of the circumflex artery, so no bypass operation could be attempted. With IABP, this patient recovered from cardiogenic shock after 59 hours. The findings of chest X rays were also improved by IABP (Fig. 7). Case 4 A 56-year-old m a n was admitted to the clinic in February, 1976, suffering from cardiogenic shock seven hours after the onset of AMI. The shock was not alleviated i n spite of the administration of several catecholamines, so IABP was immediately initiated. Consequently, significant effects such as hernodynamic improvement a n d a n increase of urine volume were obtained, a n d coronary arteriography could be safely performed during IABP (Fig. 8).An emergency operation was performed immediately, because total occlusion of the LAD a n d hypokinesis of the anterior left ventricle were revealed through angiography. The contractility of the left ventricle was improved by aortocoronary bypass to the LAD and myocardial infarctectomy. The patient seemed to be doing well postoperatively, but he died of low cardiac output associated with myocardial hemorrhagic infarction, because the operation was performed 28 hours after acute myocardial infarction. Case 13 A 67-year-old woman was admitted to the clinic because of severe cardiogenic shock due to VSD two days after the onset of AMT. With immediate initiation of IABP, hemodynamic changes such as systemic diastolic pressure, pulmonary pressure
FIG.7. Chest X ray (case 12) a) on admission, b) two days after admission and c) on discharge.
and QP/QS improved, but because of increasing pulmonary edema, a n emergency coronary arteriography was performed five days after initiation of IABP (Fig. 9). Subsequently, total occlusion of the proximal portion of the LAD was found by coronary arteriography during IABP. In a n emergency operation, a large postinfarction VSD was closed and a n infarctectomy was simultaneously carried out with the use of Teflon@felt. Unfortunately, the patient died because of uncontrollable bleeding from the suturing line of the fragile left ventricle.
DISCUSSION Indications and Contraindications for IABP Indications for the use of IABP are *-I5 1) a fall of systolic blood pressure to less than 90 mmHg, 2) a decrease of urine volume to less than 20 mllhr, 3) a rise i n the PAWP to more than 20 mmHg and 4) peripheral circulatory disturbance. Recently, IABP h a s been widely employed in low cardiac output syndrome after cardiac surgery, for examination i n p a t i e n t s with severe unstable a n g i n a a n d endotoxin shock as well as cardiogenic ~hock.l’-’~ Contraindications for the use of IABP are 1) severe disease other than cardiac disease, 2) severe aortic insufficiency and remarkable changes of the aortic wall, a n d 3) irreversible brain damage.
274
August, 1979
IABP f o r Cardiogenic Shock After AMI
GOT 103 GPT 32 C P K 165 WBC 4(m
CAG VF
L V graphy V.F
B.P
-/----
nn
UlnS
[U/,
Feb.27’76 Feb. 28 2k
4
a
12
16
20
n Feb 29 24
NOV 22
4
FIG.8. Clinical course during IABP (case 4).
21
24
25
26
27
ZB
29
30
FIG.9. Clinical course during IABP (case 13)
Management and Timing of Coronary Arteriography during IABP Monitoring of arterial pressure and ECG as well as Swan-Ganz catheterization are necessary prior to performing IABP. By maintenance of a slight hypervolemic condition, hemodynamics can be improved during IABP. If the systolic pressure was under 50 mmHg, no effect of IABP could be obtained. I n this condition, administration of a vasopressor was necessary for the successful use of IABP.’9-23Antiarrhythmic drugs such as procainamide a n d Lidocaine, along with pacemaking, should be employed in the incidence of refractory arrhythmias to maintain the effect of IABP. I n general, hemodynamic improvement will be obtained if IABP can be satisfactorily performed, a n d the patient’s condition will stabilize six to eight hours after initiation of pumping. If no hemod y n a m i c improvement i s observed, emergency coronary arteriography during IABP should be performed and the administration of inotropic agents should be increased. Weaning from IABP It is very important to accurately evaluate when the patient should be weaned from IABP. If IABP is properly applied, the patient’s condition will stabilize. Weaning from IABP should then be attempted by stopping the pump or decreasing the assistance rate (2 to 1,4 to 1,8to 1)of the pumping. If, following temporary discontinuation of IABP after 24-48 hours, certain conditions occur (mean arterial pressure under 60 mmHg; PAWP greater t h a n 20 mmHg; cardiac index under 2.0 L/min), IABP should be If no hemodynamic changes occur, the balloon catheter can be carefully removed in the following 12 hours.
According to the recent literature, 25-30% of patients with cardiogenic shock caused by myocardial infarction have been weaned from IABP.24Recently, good results have been obtained by simultaneous procedures with I A B P a n d emergency surgical i n t e r v e n t i ~ n .’@,” ~~~, Complications of IABP I n three of 16 cases, autopsies were performed which showed no complications such as aortic dissection or laceration as a result of the use of IABP. Further, there was no rupture of the balloon or disturbance i n the pump system. With wider clinical use of IABP, several complications such as ischemic changes in lower extremities, injury of the aortic wall and hemolysis have been reported i n 4-16% of the cases by Weber, Bolooki and Alpert.53’S325 The complication occurring with greatest frequency was circulatory disturbance in the lower extremities caused by emboli or thrombi which occurred a t the time of insertion of the balloon catheter. To avoid thrombus formation, heparin (1 mg/kg) should be administered a t four-to-six-hour interv a l ~ . ’ .Pulsation ~~ of the dorsal artery in which the balloon is inserted should be routinely controlled.
CONCLUSIONS Conclusions regarding the management of patients with cardiogenic shock following acute myocardial infarction are as follows: Firstly, IABP should be immediately used in cardiogenic shock unresponsive to usual medical treatment because it is the safest and most effective procedure. Secondly, angiographic evaluation should be carried out in all patients within 24 hours after initiation of IABP. Thirdly, surgical intervention should be performed,
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Artificial Organs
if indicated, in all patients who reveal IABP dependence. Recently, IABP has also been employed in the operating room with patients who are suffering from ischemic myocardium during open-heart surgery as well as in the CCU in patients with lifethreatening infarction and severe refactory angina. Good results have been obtained with this procedure. As a result of these experiences, the authors intend to employ IABP, with consideration of surgical intervention, in patients with cardiogenic shock and mechanical complications (VSD, MR) secondary to acute myocardial infarction.26-28
References 1. MOULOPOULOS, S. D., TOPAZ,S., KOLFF, W. J. Diastolic
balloon pumping (with carbon dioxide) i n the aorta: a mechanical assistance to failing circulation. Am H e a rt J , 63:669, 1972. S., FREED,P. S., PHILLIPS,S. 2. KANTROWITZ, A., TJONNELAND, ,J., BUTNER,A. N., SHERMAN, J . Initial clinical experience with intra-aortic balloon pumping i n cardiogenic shock. .JAMA, 203:113, 1968. 3. BUCKLEY,M. J., LEINBACH,R. C., KASTOR,J. A., LEARD,J. D., KANTROWITZ, A. R., MADRAS,P. N., SANDERS,C. A,, AUSTEN, W. G. Hemodynamic evaluation of intra-aortic balloon pumping i n man. Circulation, 41(S-2):11-130, 1970. 4. BREGMAN, D., PARODI,E. N., EDIE,R. N., BOWMAN, F. O., REEMTSMA,K., MALM,J. R. Intraoperative unidirectional intra-aortic balloon pumping in the management of left ventricular power failure. J Thorac Cardiovasc Surg, 701010, 1975. 5. WEBER,K. T., JANICKI,J. S. Intra-aortic balloon counterpulsation: a review of physiological principles. Clinical results and device safety. Ann Thorac Surg, 17502, 1974. 6. OKADA,M.. OKUNO,K., IIZUKA,M., SHIOZAWA, T., ASADA,S. Effect of assisted circulation for acute myocardial infarction: especially about intraaortic balloon pumping. Jpn J Artif Organs, 4926, 1975. 7. ASADA,S., OKADA,M. Mechanical circulatory assistance. J p n J Igakuno Ayumi, 105:449, 1978. 8. DUNKMAN, W. B., LEINBACH, R. C., BUCKLEY, M. J., MUNDTH, E. D., KANTROWITZ, A. R., AUSTEN,W. G., SANDERS, C.A. Clinical a n d hemodynamic results of intra-aortic balloon pumping a n d surgery for cardiogenic shock. Circulation, 46:465, 1972. 9. BREGMAN,D. Mechanical support of the failing heart. Curr Probl Surg, 131, 1976. 10. MUNDTH,E. D. Mechanical and surgical interventions for the reduction of myocardial ischemia. Circulation, 53(S-1):176, 1976. 11. LORENTE,P., DELABRE,M., MASQUET,C., GOURGON, R. A statistical prognostic study of pump failure in acute myocardial infarction. Cardiovasc Res, 9:420, 1975. J., GILBERT,B. W., KELLY, 12. GOLDMAN, B. S., GUNSTENSTEN, T. C., SCULLY,H., WILLIAMS,W. G., ADELMAN, A. Increasing operability a n d survival with intra-aortic balloon pump assist. C a n J Surg, 19:69, 1976.
276
3. FEOLA,M., WIENER,L., WALINSKY, P., KASPARIAN, H., DUCA, P., GOTTLIEB,R., BREST,A., TEMPLETON,J. Improved survival after coronary bypass surgery in patients with poor left ventricular function. Role of intra-aortic balloon counterpulsation. Am J Cardiol, 39:1021, 1977. 4. BOLOOKI,H., WILLIAMS,W., THURER,R. J., VARGAS,A., A. Clinical and KAISER,G. A., MACK, F., GHAHRAMANI, hemodynamic criteria for use of the intra-aortic balloon pump in patients requiring cardiac surgery. J Thorac Cardiovasc Surg, 72756, 1976. 15. BOLOOKI,H. Clinical Application of the Zntra-Aortic Balloon Pump. Futura Publishing Co., Mount Kisco, New York, U.S.A., 1977. 16. WEINTRAUB, R. M., AROESTY,J. M. The role of intra-aortic balloon pumping a nd surgery in the treatment. of preinfarction angina. Chest, 69707, 1976. 17. KAISER,G. C., MARCO,J. D., BARNER,H. B., CODD,J. E., LAKS,H., WILLMAN,V. Intra-aortic balloon assistance. Ann Thorac Surg, 21:487, 1976. 18. RUSSELL,R. O., RACKLEY, C. E. Techniques a nd procedures. Hernodynamic Monitoring i n a Coronary Intensive Care Unit.Futura Publishing Co., Mount Kisco, New York, U.S.A., p. 31, 1974. J. S., ROSENBAUM, A., FREED,P. S., JARON,D., 19. KRAKAUER, KANTROWITZ, A. Clinical management ancillary to phaseshift balloon pumping in cardiogenic shock: preliminary comments. Am J Cardiol, 27:123, 1971. 20. LEINBACH, R. C., DINSMORE, R. E., MUNDTH, E. D., BUCKLEY, M. J., DUNKMAN, W. B., AUSTEN,W. G., SANDERS,C. A. Selective coronary a nd left ventriculography during intraaortic balloon pumping for cardiogenic shock. Circulation, 452345, 1972. 21. FERNANDEZ, J. J., FELDMAN,M. J., SCHOCKET, L. Coronary arteriography by percutaneous transfemoral technique in patients on intra-aortic counterpulsation. Cathet Cardiovasc Diag, 3:87, 1977. 22. FEOLA,M., ADACHI,M., AKERS,W. W., Ross, J . N., WIETING, D. W., KENNEDY, J. H. Intra-aortic balloon pumping i n the experimental animal: effects and problems. Am J Cardiol, 27:129, 1971. 23. GROSSER,K. D., HELLER,A., ASBECK,F., HUBNER,W., J. Die behandKRUGER, H., VOGEL,W., IMIG,W., LENNARTZ, lung des kardiogenen schocks bei akutem herzinfarkt mit de r intra -a orta le n ballonpulsation. Dtsch Med Wsch, 101:977, 1976. 24. IGO, S. R., HIBBS,C. W., TRONO,R., FUQUA,J.M., EDMONDS, C. H., LEACHMAN, C. J., BREWER,M. A., HOLUB, D. A., NORMAN,J. C. Intra-aortic balloon pumping: theory and practice. Experience with 325 patients. Artif Or -gans.. 2(3):249, 1978: E. K.. GIELCHINSKY. I.. GILBERT.L.. 25. ALPERT.J.. BHAKTAN. BRENER', B: J., BRIEF,'D. K.,'PARSONNET,V. vascular cim: plications of intra-aortic balloon pumping. Arch Surg, 111:1190, 1976. R. C., SANDERS,C. A., BUCKLEY, 26. GOLD, H. K., LEINBACH, M. J., MUNDTH,E. D., AUSTEN,W. G. Intra-aortic balloon pumping for ventricular septa1 defect or mitral regurgitation complicating acute myocardial infarction. Circulation, 47:1191, 1973. 27. MUNDTH,E. D. Surgery for mechanical complications after acute myocardial infarction. Presented at J p n Assoc Coronary Surg, Tokyo, J a pa n, Sept., 1978. T., OKUNO,K., IIZUKA, M., 28. OKADA,M., CHEN,C., SHIOZAWA, MATSUDA,S., YONEDA,K., YANO,A., KAWAI,M., ASADA,S. Studies on mechanical circulatory assistance for acute myocardial infarction. Heart (Jpn), 8:778, 1976.
August, 1979
Experimental and Clinical Studies on the Effect of Intra-Aortic Balloon Pumping for Cardiogenic Shock Following Acute Myocardial Infarction Masayoshi Okada, Takuo Shiozawa, Masashi Iizuka, Kunio Okuno, Chuan Chung Chen, Shozo Matsuda, Kozo Yoneda, Atsushi Yano, Masaru Kawai and Sakae Asada ABSTRACT The effect of intra-aortic balloon pumping (IABP) on cardiogenic shock following acute myocardial infarction was studied experimentally and clinically. Effects of IABP on hemodynamic and electrocardiographic changes were studied with cardiogenic shock which was produced by multiple ligation of the coronary artery in dogs. Consequently, the hemodynamics as well as the ECG could be improved by diastolic augmentation and systolic unloading during IABP. But, these favorable effects of IABP were not seen in dogs whose infarcted area involved more than 50% of the free wall of the left ventricle. These facts were seen clinically in three autopsied cases. IABP was also attempted in dogs with complications such as ventricular septal defect (VSD) and mitral regurgitation (MR) following acute myocardial infarction, and significant improvement w a s obtained by IABP. No effects of IABP were seen in these series, however, when the value of the pulmonary-to-systemic flow ratio was over 4.5 in the VSD group and the mean left atrial pressure was more than 30 mmHg i n the MR group. Clinically, IABP was employed in 16 patients with cardiogenic shock secondary to acute myocardial infarction. Six (37.5%)were weaned from IABP. It can be concluded that IABP is effective i n improving hernodynamics as well as the ECG.
INTRODUCTION With the development of the coronary care unit and use of the pacemaker, the number of rhythm deaths due to acute myocardial infarction has decreased remarkably, but cardiogenic shock following acute myocardial infarction (AMI) is still associated with a high mortality rate.’-5 To decrease the mortality rate in patients with cardiogenic shock, experiment a l a n d clinical studies on intra-aortic balloon pumping were p e r f ~ r m e d . ~ ~ ’ EXPERIMENTAL STUDIES The Effect of IABP on Cardiogenic Shock The effect of IABP on acute myocardial infarction with cardiogenic shock was observed in 94 dogs. The chest was opened in the fourth intercostal space under endotracheal anesthesia, a n d respiration was maintained with a respirator. A balloon catheter was inserted through the femoral artery and located at the thoracic descending aorta as its tip came out at the distal portion of the origin of the subclavian artery (Fig. 1). The effect of IABP on hemodynamic a n d electrocardiographic changes was studied in the dogs in which AM1 was produced by multiple ligations of the coronary arteries. Consequently, significant increases of 40% in aortic diastolic pressure, 30% in cardiac output and 30% in coronary blood flow were recorded during BP ImmHg)
acute myocardial infarction, cardiogenic shock, intra-aortic balloon pumping (IABP), ventricular septal defect, mitral regurgitation From the 2nd Department of Surgery, Kobe University School of Medicine, Kobe, Japan. Address for correspondence: Masayoshi Okada, M.D., 2nd Department of Surgery, hobe University School of Medicine, 650 Kobe, Ikuta-ku Kusunoki-cho 7. Japan.
SYSTOLE
This paper was presented, in part, at the VIII World Congress of Cardiology, September. 1978, Tokyo, Japan.
D1 ASTOLE
FIG. 1. Schematic illustration of IABP.
27 1
Vol. 3, No. 3
Artificial Organs Ao. d i r s t .
Ao. 5 y r t . P .
0 Ing.
Ao.
1
syst.
3 hrr
P.
0 Iig.
1
3 hrs
Ao. d i s s t . P.
a.
c. 0.
P.
1
Iig.
c. 0.
diastole. On the other hand, a decrease of 20% in left ventricular pressure and aortic systolic pressure, and a fall of 15%in left ventricular end-diastolic pressure were also observed during systole. From these findings, the effects of diastolic augmentation and systolic unloading by IABP were clearly recognized (Fig. 2a). However, these favorable effects of IABP were not obtained in dogs in which the infarcted area was greater than 50% of the free wall of the left ventricle (Fig. 2b). The Effect o f I A B P on P o s t i n f a r c t i o n Mechanical Complications The effect of IABP on dogs with induced ventricular septa1 defect and mitral regurgitation following acute myocardial infarction was studied. VSD was created by tearing of the ventricular septum through the right ventricle, and MR was created by rupture of the chorda tendineae of the mitral valve (Fig. 3). The hemodynamic changes after creation of VSD secondary to myocardial infarction were significant decreases of 29% in mean aortic pressure, 20% in left ventricular systolic pressure, 46% in cardiac output and 23% in maximum dp/dt. The authors observed an increase of 13%in right ventricular pressure a n d 11%in pulmonary pressure related to the size of VSD. IABP was soon initiated causing increases of 7% in mean aortic pressure a n d 13%in cardiac output, a n d decreases of 10% in right ventricular pressure, 7%in pulmonary pressure and 30% in the pulmonary-to-systemic flow ratio (QP/QS) (Fig. 4a). The hemodynamic changes after creation of MR were significant reductions of 35% i n mean aortic pressure, 36% in left ventricular pressure, 36% in cardiac output a n d 35% in maximum dp/dt, a remarkable rise of 300% in mean left atrial pressure and a n increase of 50% in wedge pressure of the pulmonary artery. Initiating IABP at this point caused increases of 9% in mean aortic pressure, 18%in cardiac output and 16% in maximum dp/dt, and decreases of 7% in left ventricular pressure, 13% in mean left atrial pressure a n d 9% in pulmonary wedge pressure (PAWP) (Fig. 4b). From these findings, it could be concluded that IABP is effective in improving hemodynamics for both VSD a n d MR following AMI, except i n dogs in which the QP/QS was over 4.5 a n d the mean pressure i n the left atrium was over 30 mmHg.’
3 hrs
b.
100
IABP
IABP
FIG.2. Hemodynamic effects of IABP. a) Infarcted area less than 50% of LV surface. b) Infarcted area more than 50% of LV surface.
bR ral Valve
CLINICAL S T U D I E S On the basis of the authors’ experimental studies, IABP was employed in 16 cases of cardiogenic shock secondary to AM1 (Table). The 16 patients
FIG.3. Schematic illustration of the creation of VSD and MR.
272
August, 1979
'1
Ao. P (mean)
a1
'1
Max dp/dt
81
IABP f o r Cardiogenic Shock After A M I *I co
L V P (syst.)
+I
RVP
a.
ranged in age from 28 to 72 years (mean: 56 years). There were 12 males and 4 females. The duration of IABP ranged from 2 to 106 hours (mean: 41 hours). Significant effects of IABP were observed in all but three cases, i n which extensive myocardial infarction w a s confirmed by electrocardiogram a n d enzyme changes. Six (37.5010) of 16 patients with cardiogenic shock due to AM1 could be weaned from IABP. Coronary arteriography was safely performed in seven patients during IABP i n which the angiographic findings suggested operative feasibility, and emergency operations (one A-C bypass, one mitral valve replacement and one VSD closure) were performed in three cases. Following are some comments on five cases: the first three with patients who recovered from cardiogenic shock with IABP; the last two involving patients whose general condition deteriorated in spite of IABP application. Emergency operations were performed in these latter two patients after coronary arteriography during IABP. Case 5 A 56-year-old man developed cardiogenic shock with complete A-V block six hours after the onset of AM1 in July, 1976. His condition was somewhat improved by the administration of isoproterenol, and a temporary transvenous pacemaker was installed and initiated soon after he was admitted to the clinic. Thereafter, improvements i n heart rate a n d blood pressure were observed and coronary angiography was continuously performed. Occlusions at the proximal portion of the right coronary artery a n d t h e distal portion of the circumflex artery were revealed in angiographic findings. Unfortunately, there were n o graftable vessels in these findings a n d no indication to operate. The patient developed cardiogenic shock 16 hours after admission. With the immediate use of IABP, disappearance of chest p a i n , a n increase of blood pressure and urine volume, a n d a decrease of central venous pressure were observed (Fig. 5). The patient, fortunately, recovered from cardiogenic shock with IABP after 74 hours. He is doing well two years later. Case 7 A 59-year-old m a n developed abrupt cardiogenic shock three days after the onset of AM1 in October, 1976. With initiation of IABP, disappearance of chest pain a n d hemodynamic improvements were observed, and he recovered fully within 39 hours (Fig. 6). Angiographic findings in this case revealed 90% stenosis a t the proximal portion of the left anterior descending artery (LAD). Case 12 A 57-year-old woman developed a shock state with complete A-V block four hours after the onset
PAP
FIG.4. Hemodynamic effects of IABP for mechanical complications following AMI. a) Effects for AM1 t VSD. b) Effects for AM1 t MR.
TABLE CLINICAL EXPERIENCES OF IABP FOR CARDIOGENIC SHOCK FOLLOWING ACUTE MYOCARDIAL INFARCTION
Age -
Case
ie x
-
Duration I IABP (hrs
lecoverec
rgiography
om Shoc
iring IABP
1
K
S
61
F
3
No
No
Z
I
T
58
F
4
NO
NO
Remarks Extensive MI
3
K
K
71
M
52
NO
Yes
4
B
S
56
M
9
NO
Yes
5
M K
56
M
74
Ye5
no
6
1
K
64
M
9
NO
Yes
Chordal rupture-MVR
7
K
T
59
M
39
Ye5
Yes
NCA 34%
8
Y
K
66
M
70
NO
No
Three vessel disease
9
N
M
72
M
10
No
No
Extensive MI
10 N T
52
M
63
Ye5
NO
11
N K
28
M
2
NO
No
N
57
F
59
Ye5
Yes
Complete A V block-pacing
I3 T K
67
F
106
N O
Yes
Emergency op i V S D c l o s ~ r e+ , n f a r c i e c i o m
Ye5
Yes
Complete A V block-pacing
NO
No
Extensive MI
No
Extensive MI A f - N S R
12 H
14
S
H
47
M
96
15
D T
44
M
4
16
F S
M 41 -
53
Yes -
Emergency I
op
A C bypa5i+mfarclectomy
Complete A V block-paclng
Emergency A C bypass
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Vol. 3, No. 3
Artificial Organs
-
-0zTent
3
.
rIsoproterenol. Nwadrenclllne
*
-Pacemaking
1 -ABP-
’
dn5m
mmHg
-1
IABP
IDO
50
,
-
8
?r
12
?‘
12
k
12
2i
12
k
12
i4
11
,’,
12
16
20
24
4
8
12
16
20
24
4
8
12
FIG.6. Clinical course during IABP (case 7).
FIG.5. Clinical course during IABP (case 5).
of myocardial infarction in June, 1977. Soon after admission to the clinic, a temporary transvenous pacemaker and IABP were simultaneously initiated. Significant effects of IABP were obtained and coronary angiography was continuously carried out during IABP. Angiographic findings suggested a hypoplastic right coronary artery and severe stenosis of the circumflex artery, so no bypass operation could be attempted. With IABP, this patient recovered from cardiogenic shock after 59 hours. The findings of chest X rays were also improved by IABP (Fig. 7). Case 4 A 56-year-old m a n was admitted to the clinic in February, 1976, suffering from cardiogenic shock seven hours after the onset of AMI. The shock was not alleviated i n spite of the administration of several catecholamines, so IABP was immediately initiated. Consequently, significant effects such as hernodynamic improvement a n d a n increase of urine volume were obtained, a n d coronary arteriography could be safely performed during IABP (Fig. 8).An emergency operation was performed immediately, because total occlusion of the LAD a n d hypokinesis of the anterior left ventricle were revealed through angiography. The contractility of the left ventricle was improved by aortocoronary bypass to the LAD and myocardial infarctectomy. The patient seemed to be doing well postoperatively, but he died of low cardiac output associated with myocardial hemorrhagic infarction, because the operation was performed 28 hours after acute myocardial infarction. Case 13 A 67-year-old woman was admitted to the clinic because of severe cardiogenic shock due to VSD two days after the onset of AMT. With immediate initiation of IABP, hemodynamic changes such as systemic diastolic pressure, pulmonary pressure
FIG.7. Chest X ray (case 12) a) on admission, b) two days after admission and c) on discharge.
and QP/QS improved, but because of increasing pulmonary edema, a n emergency coronary arteriography was performed five days after initiation of IABP (Fig. 9). Subsequently, total occlusion of the proximal portion of the LAD was found by coronary arteriography during IABP. In a n emergency operation, a large postinfarction VSD was closed and a n infarctectomy was simultaneously carried out with the use of Teflon@felt. Unfortunately, the patient died because of uncontrollable bleeding from the suturing line of the fragile left ventricle.
DISCUSSION Indications and Contraindications for IABP Indications for the use of IABP are *-I5 1) a fall of systolic blood pressure to less than 90 mmHg, 2) a decrease of urine volume to less than 20 mllhr, 3) a rise i n the PAWP to more than 20 mmHg and 4) peripheral circulatory disturbance. Recently, IABP h a s been widely employed in low cardiac output syndrome after cardiac surgery, for examination i n p a t i e n t s with severe unstable a n g i n a a n d endotoxin shock as well as cardiogenic ~hock.l’-’~ Contraindications for the use of IABP are 1) severe disease other than cardiac disease, 2) severe aortic insufficiency and remarkable changes of the aortic wall, a n d 3) irreversible brain damage.
274
August, 1979
IABP f o r Cardiogenic Shock After AMI
GOT 103 GPT 32 C P K 165 WBC 4(m
CAG VF
L V graphy V.F
B.P
-/----
nn
UlnS
[U/,
Feb.27’76 Feb. 28 2k
4
a
12
16
20
n Feb 29 24
NOV 22
4
FIG.8. Clinical course during IABP (case 4).
21
24
25
26
27
ZB
29
30
FIG.9. Clinical course during IABP (case 13)
Management and Timing of Coronary Arteriography during IABP Monitoring of arterial pressure and ECG as well as Swan-Ganz catheterization are necessary prior to performing IABP. By maintenance of a slight hypervolemic condition, hemodynamics can be improved during IABP. If the systolic pressure was under 50 mmHg, no effect of IABP could be obtained. I n this condition, administration of a vasopressor was necessary for the successful use of IABP.’9-23Antiarrhythmic drugs such as procainamide a n d Lidocaine, along with pacemaking, should be employed in the incidence of refractory arrhythmias to maintain the effect of IABP. I n general, hemodynamic improvement will be obtained if IABP can be satisfactorily performed, a n d the patient’s condition will stabilize six to eight hours after initiation of pumping. If no hemod y n a m i c improvement i s observed, emergency coronary arteriography during IABP should be performed and the administration of inotropic agents should be increased. Weaning from IABP It is very important to accurately evaluate when the patient should be weaned from IABP. If IABP is properly applied, the patient’s condition will stabilize. Weaning from IABP should then be attempted by stopping the pump or decreasing the assistance rate (2 to 1,4 to 1,8to 1)of the pumping. If, following temporary discontinuation of IABP after 24-48 hours, certain conditions occur (mean arterial pressure under 60 mmHg; PAWP greater t h a n 20 mmHg; cardiac index under 2.0 L/min), IABP should be If no hemodynamic changes occur, the balloon catheter can be carefully removed in the following 12 hours.
According to the recent literature, 25-30% of patients with cardiogenic shock caused by myocardial infarction have been weaned from IABP.24Recently, good results have been obtained by simultaneous procedures with I A B P a n d emergency surgical i n t e r v e n t i ~ n .’@,” ~~~, Complications of IABP I n three of 16 cases, autopsies were performed which showed no complications such as aortic dissection or laceration as a result of the use of IABP. Further, there was no rupture of the balloon or disturbance i n the pump system. With wider clinical use of IABP, several complications such as ischemic changes in lower extremities, injury of the aortic wall and hemolysis have been reported i n 4-16% of the cases by Weber, Bolooki and Alpert.53’S325 The complication occurring with greatest frequency was circulatory disturbance in the lower extremities caused by emboli or thrombi which occurred a t the time of insertion of the balloon catheter. To avoid thrombus formation, heparin (1 mg/kg) should be administered a t four-to-six-hour interv a l ~ . ’ .Pulsation ~~ of the dorsal artery in which the balloon is inserted should be routinely controlled.
CONCLUSIONS Conclusions regarding the management of patients with cardiogenic shock following acute myocardial infarction are as follows: Firstly, IABP should be immediately used in cardiogenic shock unresponsive to usual medical treatment because it is the safest and most effective procedure. Secondly, angiographic evaluation should be carried out in all patients within 24 hours after initiation of IABP. Thirdly, surgical intervention should be performed,
275
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Artificial Organs
if indicated, in all patients who reveal IABP dependence. Recently, IABP has also been employed in the operating room with patients who are suffering from ischemic myocardium during open-heart surgery as well as in the CCU in patients with lifethreatening infarction and severe refactory angina. Good results have been obtained with this procedure. As a result of these experiences, the authors intend to employ IABP, with consideration of surgical intervention, in patients with cardiogenic shock and mechanical complications (VSD, MR) secondary to acute myocardial infarction.26-28
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balloon pumping (with carbon dioxide) i n the aorta: a mechanical assistance to failing circulation. Am H e a rt J , 63:669, 1972. S., FREED,P. S., PHILLIPS,S. 2. KANTROWITZ, A., TJONNELAND, ,J., BUTNER,A. N., SHERMAN, J . Initial clinical experience with intra-aortic balloon pumping i n cardiogenic shock. .JAMA, 203:113, 1968. 3. BUCKLEY,M. J., LEINBACH,R. C., KASTOR,J. A., LEARD,J. D., KANTROWITZ, A. R., MADRAS,P. N., SANDERS,C. A,, AUSTEN, W. G. Hemodynamic evaluation of intra-aortic balloon pumping i n man. Circulation, 41(S-2):11-130, 1970. 4. BREGMAN, D., PARODI,E. N., EDIE,R. N., BOWMAN, F. O., REEMTSMA,K., MALM,J. R. Intraoperative unidirectional intra-aortic balloon pumping in the management of left ventricular power failure. J Thorac Cardiovasc Surg, 701010, 1975. 5. WEBER,K. T., JANICKI,J. S. Intra-aortic balloon counterpulsation: a review of physiological principles. Clinical results and device safety. Ann Thorac Surg, 17502, 1974. 6. OKADA,M.. OKUNO,K., IIZUKA,M., SHIOZAWA, T., ASADA,S. Effect of assisted circulation for acute myocardial infarction: especially about intraaortic balloon pumping. Jpn J Artif Organs, 4926, 1975. 7. ASADA,S., OKADA,M. Mechanical circulatory assistance. J p n J Igakuno Ayumi, 105:449, 1978. 8. DUNKMAN, W. B., LEINBACH, R. C., BUCKLEY, M. J., MUNDTH, E. D., KANTROWITZ, A. R., AUSTEN,W. G., SANDERS, C.A. Clinical a n d hemodynamic results of intra-aortic balloon pumping a n d surgery for cardiogenic shock. Circulation, 46:465, 1972. 9. BREGMAN,D. Mechanical support of the failing heart. Curr Probl Surg, 131, 1976. 10. MUNDTH,E. D. Mechanical and surgical interventions for the reduction of myocardial ischemia. Circulation, 53(S-1):176, 1976. 11. LORENTE,P., DELABRE,M., MASQUET,C., GOURGON, R. A statistical prognostic study of pump failure in acute myocardial infarction. Cardiovasc Res, 9:420, 1975. J., GILBERT,B. W., KELLY, 12. GOLDMAN, B. S., GUNSTENSTEN, T. C., SCULLY,H., WILLIAMS,W. G., ADELMAN, A. Increasing operability a n d survival with intra-aortic balloon pump assist. C a n J Surg, 19:69, 1976.
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3. FEOLA,M., WIENER,L., WALINSKY, P., KASPARIAN, H., DUCA, P., GOTTLIEB,R., BREST,A., TEMPLETON,J. Improved survival after coronary bypass surgery in patients with poor left ventricular function. Role of intra-aortic balloon counterpulsation. Am J Cardiol, 39:1021, 1977. 4. BOLOOKI,H., WILLIAMS,W., THURER,R. J., VARGAS,A., A. Clinical and KAISER,G. A., MACK, F., GHAHRAMANI, hemodynamic criteria for use of the intra-aortic balloon pump in patients requiring cardiac surgery. J Thorac Cardiovasc Surg, 72756, 1976. 15. BOLOOKI,H. Clinical Application of the Zntra-Aortic Balloon Pump. Futura Publishing Co., Mount Kisco, New York, U.S.A., 1977. 16. WEINTRAUB, R. M., AROESTY,J. M. The role of intra-aortic balloon pumping a nd surgery in the treatment. of preinfarction angina. Chest, 69707, 1976. 17. KAISER,G. C., MARCO,J. D., BARNER,H. B., CODD,J. E., LAKS,H., WILLMAN,V. Intra-aortic balloon assistance. Ann Thorac Surg, 21:487, 1976. 18. RUSSELL,R. O., RACKLEY, C. E. Techniques a nd procedures. Hernodynamic Monitoring i n a Coronary Intensive Care Unit.Futura Publishing Co., Mount Kisco, New York, U.S.A., p. 31, 1974. J. S., ROSENBAUM, A., FREED,P. S., JARON,D., 19. KRAKAUER, KANTROWITZ, A. Clinical management ancillary to phaseshift balloon pumping in cardiogenic shock: preliminary comments. Am J Cardiol, 27:123, 1971. 20. LEINBACH, R. C., DINSMORE, R. E., MUNDTH, E. D., BUCKLEY, M. J., DUNKMAN, W. B., AUSTEN,W. G., SANDERS,C. A. Selective coronary a nd left ventriculography during intraaortic balloon pumping for cardiogenic shock. Circulation, 452345, 1972. 21. FERNANDEZ, J. J., FELDMAN,M. J., SCHOCKET, L. Coronary arteriography by percutaneous transfemoral technique in patients on intra-aortic counterpulsation. Cathet Cardiovasc Diag, 3:87, 1977. 22. FEOLA,M., ADACHI,M., AKERS,W. W., Ross, J . N., WIETING, D. W., KENNEDY, J. H. Intra-aortic balloon pumping i n the experimental animal: effects and problems. Am J Cardiol, 27:129, 1971. 23. GROSSER,K. D., HELLER,A., ASBECK,F., HUBNER,W., J. Die behandKRUGER, H., VOGEL,W., IMIG,W., LENNARTZ, lung des kardiogenen schocks bei akutem herzinfarkt mit de r intra -a orta le n ballonpulsation. Dtsch Med Wsch, 101:977, 1976. 24. IGO, S. R., HIBBS,C. W., TRONO,R., FUQUA,J.M., EDMONDS, C. H., LEACHMAN, C. J., BREWER,M. A., HOLUB, D. A., NORMAN,J. C. Intra-aortic balloon pumping: theory and practice. Experience with 325 patients. Artif Or -gans.. 2(3):249, 1978: E. K.. GIELCHINSKY. I.. GILBERT.L.. 25. ALPERT.J.. BHAKTAN. BRENER', B: J., BRIEF,'D. K.,'PARSONNET,V. vascular cim: plications of intra-aortic balloon pumping. Arch Surg, 111:1190, 1976. R. C., SANDERS,C. A., BUCKLEY, 26. GOLD, H. K., LEINBACH, M. J., MUNDTH,E. D., AUSTEN,W. G. Intra-aortic balloon pumping for ventricular septa1 defect or mitral regurgitation complicating acute myocardial infarction. Circulation, 47:1191, 1973. 27. MUNDTH,E. D. Surgery for mechanical complications after acute myocardial infarction. Presented at J p n Assoc Coronary Surg, Tokyo, J a pa n, Sept., 1978. T., OKUNO,K., IIZUKA, M., 28. OKADA,M., CHEN,C., SHIOZAWA, MATSUDA,S., YONEDA,K., YANO,A., KAWAI,M., ASADA,S. Studies on mechanical circulatory assistance for acute myocardial infarction. Heart (Jpn), 8:778, 1976.
