Late development of intractable ventricular tachycardia after acute myocardial infarction Four cases are reported in which medically refractory and ultimately fatal ventricular tachycardia developed relatively late during hospital convalescence from acute myocardial infarction. All 4 had tachycardia refractory to combinations of antiarrhythmic agents, and they required almost continuous ventricular defibrillation. Mechanical circulatory assistance (Avco intra-aortic balloon pumping) proved ineffective in controlling the recurrent arrhythmias. Emergency cardiac catheterization performed in 3 patients and postmortem examination in the fourth patient demonstrated the following: (1) complete occlusion of the left anterior descending coronary artery near its origin and diffuse circumflex obstruction; (2) extensive myocardial infarction involving two thirds of the anterior wall; and (3) ventricular ejection fractions of less than 25 per cent. Emergency surgery also proved ineffective in 2 patients. These findings suggest that recurrent ventricular tachycardia developing late in the course of recovery from an acute myocardial infarction is an ominous prognostic sign in patients such as these. Mechanical circulatory assistance in combination with various antiarrhythmic agents appears to be of little benefit in controlling this type of ventricular arrhythmia. Georgina K. Sehapayak, M.D., John T. Watson, Ph.D., George C. Curry, M.D., Stephen P. Londe, M.D., Charles B. Mullins, M.D., James T. Willerson, M.D., * and Winfred L. Sugg, M.D., Dallas, Texas Recurrent episodes of ventricular tachy- cardia-ventricular fibrillation, occurring as a late complication of acute myocardial in- farction, are difficult to control and are as- sociated with a high mortality rate, despite From the Pauline and Adolph Weinberger Laboratory for Cardiopulmonary Research of the Department of Internal Medicine. the Department of Thoracic and Cardiovascular Surgery, and the Department of Radiology, University of Texas Southwestern Medical School at Dallas, Da1las, Texas. This work was performed during Dr. Sehapayak's tenure as a Postdoctoral Research Fe1low supported by Na- tional Heart and Lung Institute Training Grant HL 05812. The work was prepared during Dr. Mullins' tenure as a Teaching Scholar of the American Heart Association. Received for publication Feb. 6, 1974. Address for reprints: James T. Willerson, M.D., Cardio- pulmonary-D-710, 5323 Harry Hines Blvd., Dallas, Texas 75235. • Established Investigator of the American Heart Associa- tion. 818 aggressive therapy with antiarrhythmic drugs and direct-current cardioversion."' Although the final outcome has been con- sidered to be related to the extent of the underlying myocardial damage, a detailed study of the anatomic lesions in these pa- tients has not been reported. The purpose of this report is to describe the case his- tories of 4 patients with intractable ven- tricular tachycardia-ventricular fibrillation occurring late in the course of acute myo- cardial infarction. In these patients, cath- eterization, surgical, and postmortem find- ings are available. The resistant ventricular arrhythmias were managed by means of two relatively new modes of therapy: me- chanical circulatory assistance and emer- gency myocardial revascularization and in- farctectomy.
Late development of intractable ventricular tachycardia after acute myocardial infarction
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Late development of intractable ventricular tachycardia after acute myocardial infarctionLate development of intractable ventricular tachycardia after acute myocardial infarction Four cases are reported in which medically refractory and ultimately fatal ventricular tachycardia developed relatively late during hospital convalescence from acute myocardial infarction. All 4 had tachycardia refractory to combinations of antiarrhythmic agents, and they required almost continuous ventricular defibrillation. Mechanical circulatory assistance (Avco intra-aortic balloon pumping) proved ineffective in controlling the recurrent arrhythmias. Emergency cardiac catheterization performed in 3 patients and postmortem examination in the fourth patient demonstrated the following: (1) complete occlusion of the left anterior descending coronary artery near its origin and diffuse circumflex obstruction; (2) extensive myocardial infarction involving two thirds of the anterior wall; and (3) ventricular ejection fractions of less than 25 per cent. Emergency surgery also proved ineffective in 2 patients. These findings suggest that recurrent ventricular tachycardia developing late in the course of recovery from an acute myocardial infarction is an ominous prognostic sign in patients such as these. Mechanical circulatory assistance in combination with various antiarrhythmic agents appears to be of little benefit in controlling this type of ventricular arrhythmia.
Georgina K. Sehapayak, M.D., John T. Watson, Ph.D., George C. Curry, M.D., Stephen P. Londe, M.D., Charles B. Mullins, M.D., James T. Willerson, M.D., * and Winfred L. Sugg, M.D., Dallas, Texas
Recurrent episodes of ventricular tachy- cardia-ventricular fibrillation, occurring as a late complication of acute myocardial in- farction, are difficult to control and are as- sociated with a high mortality rate, despite
From the Pauline and Adolph Weinberger Laboratory for Cardiopulmonary Research of the Department of Internal Medicine. the Department of Thoracic and Cardiovascular Surgery, and the Department of Radiology, University of Texas Southwestern Medical School at Dallas, Da1las, Texas.
This work was performed during Dr. Sehapayak's tenure as a Postdoctoral Research Fe1low supported by Na- tional Heart and Lung Institute Training Grant HL 05812. The work was prepared during Dr. Mullins' tenure as a Teaching Scholar of the American Heart Association.
Received for publication Feb. 6, 1974.
Address for reprints: James T. Willerson, M.D., Cardio- pulmonary-D-710, 5323 Harry Hines Blvd., Dallas, Texas 75235.
• Established Investigator of the American Heart Associa- tion.
818
aggressive therapy with antiarrhythmic drugs and direct-current cardioversion."' Although the final outcome has been con- sidered to be related to the extent of the underlying myocardial damage, a detailed study of the anatomic lesions in these pa- tients has not been reported. The purpose of this report is to describe the case his- tories of 4 patients with intractable ven- tricular tachycardia-ventricular fibrillation occurring late in the course of acute myo- cardial infarction. In these patients, cath- eterization, surgical, and postmortem find- ings are available. The resistant ventricular arrhythmias were managed by means of two relatively new modes of therapy: me- chanical circulatory assistance and emer- gency myocardial revascularization and in- farctectomy.
Volume 67
Number 5
Table I. Coronary anatomy
Case No. Left main ILeft anterior descending I Circumflex IRight coronary artery
Severe diffuse disease Completely occluded
Total occlusion proximally, with retrograde filling from the left system
NormalMarked narrowing along distal branches
Fifty per cent luminal Complete occlusion, narrowing 1 cm. from its
origin, by an orga- nized thrombus with a distal 50 per cent narrowing
Completely occluded Diffuse peripheral stenosis
Normal Completely occluded proximally, with dis- tal retrograde filling from the right system
Minimal arterio- Complete occlusion, 1 sclerosis without em. from its origin, significant ob- by an organized struction thrombus (1 mo. old),
with considerable fibrous intimal thick- ening distally
Completely occluded; distal portion filled retrograde from the right system
Normal
Case reports
CASE 1 (PMH 437189). A 50-year-old man was admitted to Parkland Memorial Hospital with severe chest pain, pulmonary edema, and elec- trocardiographic changes consistent with an ex- tensive anterior myocardial infarction and frequent premature ventricular contractions. He was treated with digitalis, diuretics, lidocaine, and respiratory support.
The patient continued to have intermittent but rare chest pain and mild left ventricular failure. He developed recurrent premature ventricular con- tractions followed by ventricular tachycardia (270 beats per minute) on the fourth day after admis- sion, for which he required a combination of lido- caine, Dilantin, procainamide, and quinidine for suppression. Premature ventricular contractions continued intermittently, and on the eighth day after admission the patient again developed re- current ventricular tachycardia, requiring more than eighty direct-current countershocks for con- version to regular sinus rhythm. His blood pres- sure remained at 105 to 110 mm. Hg systolic during sinus rhythm but could not be obtained during episodes of ventricular tachycardia. An Avco intra-aortic balloon assist device was utilized in the hope of preventing the recurrent arrhyth- mia. However, two episodes of ventricular tachy- cardia occurred after the balloon was inserted.
It became apparent that the balloon assist was unsuccessful. The patient was studied by cardiac catheterization and found to have severe three-
vessel coronary artery disease (Tables I and II). Support with the circulatory assist device was continued; however, 8 hours later, the patient de- veloped almost constant ventricular tachycardia, requiring approximately two-hundred defibrilla- tions. In desperation, we decided to attempt an infarctectomy. The major finding at the time of operation was a large area of acute infarction with slight paradoxical motion involving the apex and distal half of the anterior wall of the left ventricle. This infarcted area was excised. A saphenous vein graft was placed into the distal right coronary artery, and blood flow was mea- sured at 60 rnl. per minute. Weaning the patient from cardiopulmonary bypass was difficult and required intra-aortic balloon pumping for circula- tory support. The heart maintained a sinus rhythm with no further premature ventricular contractions or episodes of ventricular tachycardia. However, the blood pressure was dependent on norepineph- rine and counterpulsation for support, and the patient died 11 hours postoperatively.
CASE 2 (PMH 438795). A 57-year-old dia- betic, hypertensive woman who had experienced two previous myocardial infarctions was admitted with an acute anteroseptal myocardial infarction. She had signs. of acute left ventricular failure manifested by a summation gallop, pulmonary edema, and sinus tachycardia (150 beats per minute). She had been taking digitalis for pul- monary congestion in the past, and the chest x-ray film on admission revealed cardiomegaly with
8 2 0 Sehapayak et al.
Table II. Left ventricular function
The Journal at
Thoracic and Cardiovascular
(mm. Hg) (mI.) (mI.) Ejection
fraction (%) Left ventricular angiogram or
postmortem findings
Case 2 (cath. data)
18
18
166
273
131
212
23
21
22
Only contraction was at the base of the heart with very slight paradoxical pulsa- tion of the distal anterolateral wall; mild mitral regurgitation
Akinesis of the anterolateral wall; small left ventricular apical aneurysm
Moderately dilated; wall thickness 15 mm.; large, healing, transmural anteroseptal in- farct involving two thirds of the anterior wall of the left ventricle and the anterior two thirds of the septum
Only contraction was at the base of the heart; distal half of the anterolateral and inferior walls were akinetic
Legend: LVEDP, Left ventricular end-diastolic pressure. LVEDV, Left ventricular end-diastolic volume. LVESV, Left ven- tricular end-systolic volume.
'Volumes calculated by method of Kasser, I. S., and Kennedy, J. W.22
predominant left ventricular enlargement. She was treated with diuretics and respiratory assistance.
During the first 3 days of hospitalization, the patient developed a multitude of rhythm and con- duction disturbances including paroxysmal atrial tachycardia with 1: 1 conduction, intermittent pre- mature ventricular contractions, sinus tachycardia, intermittent first-degree atrioventricular block, left anterior hemiblock, and intermittent right and left bundle branch block. She was treated with temporary transvenous pacing, quinidine, and lido- caine. On the fourth hospital day, the patient be- came hypotensive and developed a persistent sinus tachycardia. Norepinephrine was used to main- tain the blood pressure at 100/80 mrn. Hg, Hemo- dynamics demonstrated a pulmonary artery pres- sure of 32/20 and a mean capillary wedge pres- sure of 20 mm. Hg, An Avco intra-aortic balloon was inserted and norepinephrine was withheld. On the twelfth hospital day the balloon support was successfully discontinued. Blood pressure was stable, but she continued to have a persistent sinus tachycardia. On the seventeenth hospital day she developed premature ventricular contractions and an episode of ventricular tachycardia. She was treated with lidocaine at first and then was given maintenance doses of procainamide. On the nine- teenth day the patient had a Stokes-Adams syn- copal attack due to another episode of ventricular tachycardia. Treatment with large doses of quini- dine, procainamide, and lidocaine was continued, and diphenylhydantoin was added to the regimen. A transvenous pacemaker was inserted.
It was not possible to decrease or discontinue any of the antiarrhythmic agents without repeated episodes of ventricular tachycardia. On Day 22
the balloon was reinserted and cardiac catheteriza- tion was performed (Tables I and II). The left ventricular angiogram is shown in Fig. 1. Ven- tricular tachycardia continued to recur, requiring almost continuous defibrillation. Surgical therapy was then attempted. A large apical and antero- lateral left ventricular infarct was visualized but considered unresectable because the resultant small left ventricular chamber would not have been adequate to support life. The infarcted area was plicated with heavy sutures in the hope of obliterating the focus of ventricular irritability while maintaining an adequate left ventricular filling volume. A saphenous vein bypass to a small left anterior descending artery was accomplished. Hemodynamics were immediately satisfactory, and a lidocaine drip was maintained prophylactically. She initially did well but 48 hours postoperatively developed another episode of ventricular tachy- cardia that required direct-current cardioversion. She died the following day in asystole, unrespon- sive to the pacemaker.
CASE 3 (PMH 440296). A 57-year-old man with a history of myocardial infarction 8 years previously arrived in a state of ventricular fibrilla- tion after an acute myocardial infarction. Direct- current cardioversion was applied. The admission electrocardiogram showed an acute anteroseptal myocardial infarction. He developed recurrent epi- sodes of rapid ventricular tachycardia requiring a lidocaine drip, direct-current cardioversion, and small amounts of norepinephrine to maintain an adequate blood pressure. His condition stabilized during the first 48 hours, and the antiarrhythmic and vasopressor therapy was discontinued. The man rapidly improved and became ambulatory;
Volume 67
Number 5
Moy, 1974 Intractable tachycardia after infarction 8 2 1
Fig. 1. A, Frame from right anterior oblique view of the left ventriculogram (Case 2). The balloon was reinserted immediately prior to catheterization. The margin of the inflated balloon is outlined by the solid arrows in this end-diastolic frame. B, End-systolic frame (same case). The open arrows point to the intra-aortic catheter. Note that the balloon is now completely deflated. The severely reduced ejection fraction is evident, with decreased wall motion throughout which becomes more severe near the apex itself.
however, on the twenty-ninth day of hospitaliza- tion the patient suddenly developed ventricular fibrillation for which he required multiple fre- quent defibrillations. Approximately seventy epi- sodes of ventricular tachycardia-fibrillation necessi- tated cardioversion over a period of 1112 hours. An intra-aortic balloon was inserted but proved ineffective in maintaining blood pressure or in controlling the ventricular arrhythmia. Two hours later the patient died. Postmortem examination revealed severe and diffuse coronary atherosclero- sis (Table I).
CASE 4 (PMH 419877). A 62-year-old man was admitted with an acute anterior myocardial infarction. His course was uncomplicated for the following 10 days, but then he developed recurrent ventricular tachycardia as well as intermittent epi- sodes of supraventricular tachycardia that were partially controlled with lidocaine, procainamide, and quinidine. Because the arrhythmias became more frequent, propranolol was added to his drug regimen. An Avco intra-aortic balloon was inserted during a period of sinus rhythm in the hope that this means of support, in combination
8 2 2 Sehapayak et ai.
with the antiarrhythmic agents, would prevent the tachyarrhythmias from recurring. However, ventricular tachycardia continued to recur inter- mittently.
Cardiac catheterization on mechanical circula- tory assistance was performed with the hope that a resectable ventricular aneurysm might be pres- ent. The findings at catheterization, shown in Tables I and II, were considered indicative of inoperable cardiac disease. The patient died with ventricular tachycardia-fibrillation 24 hours later.
At postmortem examination, severe three-vessel coronary artery disease was found. A thrombus was discovered in the proximal left anterior de- scending coronary artery. Multiple areas of myo- cardial infarction involving the ventricular septum and the anterior and lateral aspects of the left ventricle were also present. The anterior wall of the left ventricle was thinned, and a recent area of septal infarction extended from the cardiac apex to within 2 rnm. of the membranous ven- tricular septum.
Discussion
Recurrent ventricular tachycardia-ventric- ular fibrillation during acute myocardial in- farction has been documented in the litera- ture."- H In these reports, the patients sur- vived after undergoing varying modes of therapy. However, in the majority of these patients, a significantly smaller number of episodes occurred over a period of several days; generally, these occurred in the first few minutes, hours, or days after a myo- cardial infarction. The distinctive feature of our cases is the late occurrence and the intractable nature of the ventricular tachyar- rhythmia after acute myocardial infarction. In these patients, ventricular tachycardia- fibrillation required virtually continuous bedside defibrillation.
Although in 2 of our patients the ar- rhythmia might be considered a complica- tion rather than the primary disease, be- cause of prior mild cardiac failure,' all 4 patients were well compensated and without congestive heart failure or significant hypo- tension at the onset of the ventricular tachy- arrhythmia. Likewise, evidence of metabolic acidosis, hypoxemia, digitalis or other drug intoxication, and hypokalemia was lacking. Therefore, it seemed logical to consider myocardial ischemia and/or myocardial
The Journal of
Thoracic and Cordiovascular
Surgery
aneurysm or dyskinetic segment to be the most likely underlying cause of the intrac- table ventricular arrhythmias. This reason- ing led to a trial of treatment with intra- aortic balloon counterpulsation in 3 of the patients when the antiarrhythmic agents were not successful.
The current indications for the use of mechanical circulatory assist devices in- clude the following': (1) cardiogenic shock, (2) acute left ventricular failure refractory to medical therapy, (3) recurrent life- threatening ventricular arrhythmias unre- sponsive to pharmacologic agents, (4) acute ventricular septal defect or mitral regurgi- tation after myocardial infarction with severe left ventricular failure, and (5) an aid in weaning from cardiopulmonary by- pass patients with marked myocardial de- pression following cardiac surgery.
At the present time, certain experimental evidence suggests that mechanical circula- tory assistance may be useful in managing serious ventricular arrhythmias," but clinical evidence is still lacking. Buckley and col- leagues" describing a patient in whom in- tra-aortic balloon pumping was used for cardiogenic shock, mentioned that previous- ly recurrent ventricular tachycardia-fibrilla- tion was controlled during the subsequent hour; however, the long-term course of that patient was not described. In patients with the opposite clinical situation, i.e., cardio- genic shock secondary to ventricular tachy- arrhythmia, Dunkman," Mundth,"" and their associates found intra-aortic balloon pumping ineffective and subjected the pa- tients to emergency infarctectomy with good results. In 3 of our patients without cardio- genic shock, intra-aortic balloon pumping proved ineffective in controlling the ven- tricular arrhythmia.
Several surgical techniques have been advanced for managing life-threatening ar- rhythmias refractory to or not well con- trolled by antiarrhythmic agents in patients with ischemic heart disease. These include aneurysmectomy or scar resectionv" and, more recently, myocardial revascularization via saphenous vein bypass grafts between
Volume 67
Number 5
May, 1974
the aorta and the coronary arteries," some- times in combination with aneurysmectomy or intarctectomy." In most instances in which surgical resection has been employed, the patients had already survived the acute stage of myocardial infarction. In some re- cent reports, however, these operations were performed during the acute stage, and the most frequent pathology found has been left ventricular aneurysm. I", 20 In patients without a clear-cut aneurysm, definite guide- lines regarding infarctectomy are not avail- able." In the 2 patients whom we operated upon, the extent of myocardium requiring resection was too large to be compatible with life. Common anatomic findings in these 2 patients were (I) severe two-vessel coronary artery disease in 1 patient and three-vessel disease in the other, with com- plete proximal occlusion of the left anterior descending coronary artery in both, and (2) severe left ventricular dysfunction, with loss of motion of at least two thirds of the left ventricular wall including the apex, and ejection fractions of less than 25 per cent. On dividing the ventriculograms into six segments, as suggested by Sanders and his associates,' we found three or more akinetic segments in both patients. This has been shown to be a poor prognostic sign for survival after coronary artery revascular- ization for patients in cardiogenic shock." Postmortem examination in the third pa- tient also showed severe triple-vessel dis- ease with complete occlusion of the left anterior descending coronary artery and severe myocardial damage involving two thirds of the left ventricular wall and inter- ventricular septum. The cardiac catheteri- zation and postmortem findings in Patient 4 in this series were similar to those noted in the other 3 patients. All 4 of these patients had massive anteroseptal myocardial infarc- tions. All 4 had lost more than 50 per cent of the left ventricular mass. However, none of these 4 patients had a sizable localized left ventricular aneurysm.
Whether or not most patients who have serious, intractable ventricular arrhythmias in this setting will have anatomic patterns
Intractable tachycardia after infarction 823
similar to those of our 4 patients remains to be determined. The development of a means of identifying the ventricular site of origin and/or the electrophysiologic mecha- nism of such ventricular arrhythmias at the time of catheterization or surgery would potentially be of great benefit.
The number of cases reported here is small. However, review of these cases sug- gests that, when intractable and almost con- tinuous ventricular tachycardia occurs rela- tively late in the course of acute myocardial infarction and is associated with a severe degree of coronary disease and myocardial damage, the patients are not likely to be benefited by intra-aortic balloon pumping or emergency surgical intervention.
Summary
Four cases are reported in which fatal, intractable ventricular tachycardia de- veloped relatively late during hospital con- valescence from acute myocardial infarc- tion. All 4 cases were refractory to the usual modes of therapy, requiring multiple frequent ventricular defibrillation. Mechani- cal circulatory assistance in the form of Avco intra-aortic balloon pumping proved ineffective in the control of these ar- rhythmias. Cardiac catheterization, per- formed in 3 of the patients during the acute stage, and postmortem examination in the fourth revealed two common findings: (1) complete occlusion of the left anterior de- scending coronary artery near its origin and diffuse severe obstruction of the cir- cumflex; (2) severe myocardial disease with infarcted areas involving at least two thirds of the anterior wall. In addition, 3 of the patients had total occlusion of the right coronary artery. Angiography demonstrated severe left ventricular dysfunction, with ejection fractions under 25 per cent in 3 of the patients. An attempt to provide myo- cardial revascularization with infarct plica- tion proved ineffective in 1 patient. In an- other patient, infarctectomy was effective in preventing further episodes of ventricular tachycardia, but that patient subsequently died with a low cardiac output syndrome.
8 2 4 Sehapayak et al.
These findings suggest that the development of recurrent ventricular tachycardia late in the course of recovery from an acute myo- cardial infarction is an ominous prognostic sign in patients with the coronary and ven- tricular anatomy described herein. Treat- ment by either circulatory assistance or sur- gical intervention may be unsuccessful.
REFERENCES
Lawrie, D. M., Higgins, M. R., Godman, M. 1., Oliver, M. F., Julian, D. G., and Donald, K. W.: Ventricular Fibrillation Complicating Acute Myocardial…
Georgina K. Sehapayak, M.D., John T. Watson, Ph.D., George C. Curry, M.D., Stephen P. Londe, M.D., Charles B. Mullins, M.D., James T. Willerson, M.D., * and Winfred L. Sugg, M.D., Dallas, Texas
Recurrent episodes of ventricular tachy- cardia-ventricular fibrillation, occurring as a late complication of acute myocardial in- farction, are difficult to control and are as- sociated with a high mortality rate, despite
From the Pauline and Adolph Weinberger Laboratory for Cardiopulmonary Research of the Department of Internal Medicine. the Department of Thoracic and Cardiovascular Surgery, and the Department of Radiology, University of Texas Southwestern Medical School at Dallas, Da1las, Texas.
This work was performed during Dr. Sehapayak's tenure as a Postdoctoral Research Fe1low supported by Na- tional Heart and Lung Institute Training Grant HL 05812. The work was prepared during Dr. Mullins' tenure as a Teaching Scholar of the American Heart Association.
Received for publication Feb. 6, 1974.
Address for reprints: James T. Willerson, M.D., Cardio- pulmonary-D-710, 5323 Harry Hines Blvd., Dallas, Texas 75235.
• Established Investigator of the American Heart Associa- tion.
818
aggressive therapy with antiarrhythmic drugs and direct-current cardioversion."' Although the final outcome has been con- sidered to be related to the extent of the underlying myocardial damage, a detailed study of the anatomic lesions in these pa- tients has not been reported. The purpose of this report is to describe the case his- tories of 4 patients with intractable ven- tricular tachycardia-ventricular fibrillation occurring late in the course of acute myo- cardial infarction. In these patients, cath- eterization, surgical, and postmortem find- ings are available. The resistant ventricular arrhythmias were managed by means of two relatively new modes of therapy: me- chanical circulatory assistance and emer- gency myocardial revascularization and in- farctectomy.
Volume 67
Number 5
Table I. Coronary anatomy
Case No. Left main ILeft anterior descending I Circumflex IRight coronary artery
Severe diffuse disease Completely occluded
Total occlusion proximally, with retrograde filling from the left system
NormalMarked narrowing along distal branches
Fifty per cent luminal Complete occlusion, narrowing 1 cm. from its
origin, by an orga- nized thrombus with a distal 50 per cent narrowing
Completely occluded Diffuse peripheral stenosis
Normal Completely occluded proximally, with dis- tal retrograde filling from the right system
Minimal arterio- Complete occlusion, 1 sclerosis without em. from its origin, significant ob- by an organized struction thrombus (1 mo. old),
with considerable fibrous intimal thick- ening distally
Completely occluded; distal portion filled retrograde from the right system
Normal
Case reports
CASE 1 (PMH 437189). A 50-year-old man was admitted to Parkland Memorial Hospital with severe chest pain, pulmonary edema, and elec- trocardiographic changes consistent with an ex- tensive anterior myocardial infarction and frequent premature ventricular contractions. He was treated with digitalis, diuretics, lidocaine, and respiratory support.
The patient continued to have intermittent but rare chest pain and mild left ventricular failure. He developed recurrent premature ventricular con- tractions followed by ventricular tachycardia (270 beats per minute) on the fourth day after admis- sion, for which he required a combination of lido- caine, Dilantin, procainamide, and quinidine for suppression. Premature ventricular contractions continued intermittently, and on the eighth day after admission the patient again developed re- current ventricular tachycardia, requiring more than eighty direct-current countershocks for con- version to regular sinus rhythm. His blood pres- sure remained at 105 to 110 mm. Hg systolic during sinus rhythm but could not be obtained during episodes of ventricular tachycardia. An Avco intra-aortic balloon assist device was utilized in the hope of preventing the recurrent arrhyth- mia. However, two episodes of ventricular tachy- cardia occurred after the balloon was inserted.
It became apparent that the balloon assist was unsuccessful. The patient was studied by cardiac catheterization and found to have severe three-
vessel coronary artery disease (Tables I and II). Support with the circulatory assist device was continued; however, 8 hours later, the patient de- veloped almost constant ventricular tachycardia, requiring approximately two-hundred defibrilla- tions. In desperation, we decided to attempt an infarctectomy. The major finding at the time of operation was a large area of acute infarction with slight paradoxical motion involving the apex and distal half of the anterior wall of the left ventricle. This infarcted area was excised. A saphenous vein graft was placed into the distal right coronary artery, and blood flow was mea- sured at 60 rnl. per minute. Weaning the patient from cardiopulmonary bypass was difficult and required intra-aortic balloon pumping for circula- tory support. The heart maintained a sinus rhythm with no further premature ventricular contractions or episodes of ventricular tachycardia. However, the blood pressure was dependent on norepineph- rine and counterpulsation for support, and the patient died 11 hours postoperatively.
CASE 2 (PMH 438795). A 57-year-old dia- betic, hypertensive woman who had experienced two previous myocardial infarctions was admitted with an acute anteroseptal myocardial infarction. She had signs. of acute left ventricular failure manifested by a summation gallop, pulmonary edema, and sinus tachycardia (150 beats per minute). She had been taking digitalis for pul- monary congestion in the past, and the chest x-ray film on admission revealed cardiomegaly with
8 2 0 Sehapayak et al.
Table II. Left ventricular function
The Journal at
Thoracic and Cardiovascular
(mm. Hg) (mI.) (mI.) Ejection
fraction (%) Left ventricular angiogram or
postmortem findings
Case 2 (cath. data)
18
18
166
273
131
212
23
21
22
Only contraction was at the base of the heart with very slight paradoxical pulsa- tion of the distal anterolateral wall; mild mitral regurgitation
Akinesis of the anterolateral wall; small left ventricular apical aneurysm
Moderately dilated; wall thickness 15 mm.; large, healing, transmural anteroseptal in- farct involving two thirds of the anterior wall of the left ventricle and the anterior two thirds of the septum
Only contraction was at the base of the heart; distal half of the anterolateral and inferior walls were akinetic
Legend: LVEDP, Left ventricular end-diastolic pressure. LVEDV, Left ventricular end-diastolic volume. LVESV, Left ven- tricular end-systolic volume.
'Volumes calculated by method of Kasser, I. S., and Kennedy, J. W.22
predominant left ventricular enlargement. She was treated with diuretics and respiratory assistance.
During the first 3 days of hospitalization, the patient developed a multitude of rhythm and con- duction disturbances including paroxysmal atrial tachycardia with 1: 1 conduction, intermittent pre- mature ventricular contractions, sinus tachycardia, intermittent first-degree atrioventricular block, left anterior hemiblock, and intermittent right and left bundle branch block. She was treated with temporary transvenous pacing, quinidine, and lido- caine. On the fourth hospital day, the patient be- came hypotensive and developed a persistent sinus tachycardia. Norepinephrine was used to main- tain the blood pressure at 100/80 mrn. Hg, Hemo- dynamics demonstrated a pulmonary artery pres- sure of 32/20 and a mean capillary wedge pres- sure of 20 mm. Hg, An Avco intra-aortic balloon was inserted and norepinephrine was withheld. On the twelfth hospital day the balloon support was successfully discontinued. Blood pressure was stable, but she continued to have a persistent sinus tachycardia. On the seventeenth hospital day she developed premature ventricular contractions and an episode of ventricular tachycardia. She was treated with lidocaine at first and then was given maintenance doses of procainamide. On the nine- teenth day the patient had a Stokes-Adams syn- copal attack due to another episode of ventricular tachycardia. Treatment with large doses of quini- dine, procainamide, and lidocaine was continued, and diphenylhydantoin was added to the regimen. A transvenous pacemaker was inserted.
It was not possible to decrease or discontinue any of the antiarrhythmic agents without repeated episodes of ventricular tachycardia. On Day 22
the balloon was reinserted and cardiac catheteriza- tion was performed (Tables I and II). The left ventricular angiogram is shown in Fig. 1. Ven- tricular tachycardia continued to recur, requiring almost continuous defibrillation. Surgical therapy was then attempted. A large apical and antero- lateral left ventricular infarct was visualized but considered unresectable because the resultant small left ventricular chamber would not have been adequate to support life. The infarcted area was plicated with heavy sutures in the hope of obliterating the focus of ventricular irritability while maintaining an adequate left ventricular filling volume. A saphenous vein bypass to a small left anterior descending artery was accomplished. Hemodynamics were immediately satisfactory, and a lidocaine drip was maintained prophylactically. She initially did well but 48 hours postoperatively developed another episode of ventricular tachy- cardia that required direct-current cardioversion. She died the following day in asystole, unrespon- sive to the pacemaker.
CASE 3 (PMH 440296). A 57-year-old man with a history of myocardial infarction 8 years previously arrived in a state of ventricular fibrilla- tion after an acute myocardial infarction. Direct- current cardioversion was applied. The admission electrocardiogram showed an acute anteroseptal myocardial infarction. He developed recurrent epi- sodes of rapid ventricular tachycardia requiring a lidocaine drip, direct-current cardioversion, and small amounts of norepinephrine to maintain an adequate blood pressure. His condition stabilized during the first 48 hours, and the antiarrhythmic and vasopressor therapy was discontinued. The man rapidly improved and became ambulatory;
Volume 67
Number 5
Moy, 1974 Intractable tachycardia after infarction 8 2 1
Fig. 1. A, Frame from right anterior oblique view of the left ventriculogram (Case 2). The balloon was reinserted immediately prior to catheterization. The margin of the inflated balloon is outlined by the solid arrows in this end-diastolic frame. B, End-systolic frame (same case). The open arrows point to the intra-aortic catheter. Note that the balloon is now completely deflated. The severely reduced ejection fraction is evident, with decreased wall motion throughout which becomes more severe near the apex itself.
however, on the twenty-ninth day of hospitaliza- tion the patient suddenly developed ventricular fibrillation for which he required multiple fre- quent defibrillations. Approximately seventy epi- sodes of ventricular tachycardia-fibrillation necessi- tated cardioversion over a period of 1112 hours. An intra-aortic balloon was inserted but proved ineffective in maintaining blood pressure or in controlling the ventricular arrhythmia. Two hours later the patient died. Postmortem examination revealed severe and diffuse coronary atherosclero- sis (Table I).
CASE 4 (PMH 419877). A 62-year-old man was admitted with an acute anterior myocardial infarction. His course was uncomplicated for the following 10 days, but then he developed recurrent ventricular tachycardia as well as intermittent epi- sodes of supraventricular tachycardia that were partially controlled with lidocaine, procainamide, and quinidine. Because the arrhythmias became more frequent, propranolol was added to his drug regimen. An Avco intra-aortic balloon was inserted during a period of sinus rhythm in the hope that this means of support, in combination
8 2 2 Sehapayak et ai.
with the antiarrhythmic agents, would prevent the tachyarrhythmias from recurring. However, ventricular tachycardia continued to recur inter- mittently.
Cardiac catheterization on mechanical circula- tory assistance was performed with the hope that a resectable ventricular aneurysm might be pres- ent. The findings at catheterization, shown in Tables I and II, were considered indicative of inoperable cardiac disease. The patient died with ventricular tachycardia-fibrillation 24 hours later.
At postmortem examination, severe three-vessel coronary artery disease was found. A thrombus was discovered in the proximal left anterior de- scending coronary artery. Multiple areas of myo- cardial infarction involving the ventricular septum and the anterior and lateral aspects of the left ventricle were also present. The anterior wall of the left ventricle was thinned, and a recent area of septal infarction extended from the cardiac apex to within 2 rnm. of the membranous ven- tricular septum.
Discussion
Recurrent ventricular tachycardia-ventric- ular fibrillation during acute myocardial in- farction has been documented in the litera- ture."- H In these reports, the patients sur- vived after undergoing varying modes of therapy. However, in the majority of these patients, a significantly smaller number of episodes occurred over a period of several days; generally, these occurred in the first few minutes, hours, or days after a myo- cardial infarction. The distinctive feature of our cases is the late occurrence and the intractable nature of the ventricular tachyar- rhythmia after acute myocardial infarction. In these patients, ventricular tachycardia- fibrillation required virtually continuous bedside defibrillation.
Although in 2 of our patients the ar- rhythmia might be considered a complica- tion rather than the primary disease, be- cause of prior mild cardiac failure,' all 4 patients were well compensated and without congestive heart failure or significant hypo- tension at the onset of the ventricular tachy- arrhythmia. Likewise, evidence of metabolic acidosis, hypoxemia, digitalis or other drug intoxication, and hypokalemia was lacking. Therefore, it seemed logical to consider myocardial ischemia and/or myocardial
The Journal of
Thoracic and Cordiovascular
Surgery
aneurysm or dyskinetic segment to be the most likely underlying cause of the intrac- table ventricular arrhythmias. This reason- ing led to a trial of treatment with intra- aortic balloon counterpulsation in 3 of the patients when the antiarrhythmic agents were not successful.
The current indications for the use of mechanical circulatory assist devices in- clude the following': (1) cardiogenic shock, (2) acute left ventricular failure refractory to medical therapy, (3) recurrent life- threatening ventricular arrhythmias unre- sponsive to pharmacologic agents, (4) acute ventricular septal defect or mitral regurgi- tation after myocardial infarction with severe left ventricular failure, and (5) an aid in weaning from cardiopulmonary by- pass patients with marked myocardial de- pression following cardiac surgery.
At the present time, certain experimental evidence suggests that mechanical circula- tory assistance may be useful in managing serious ventricular arrhythmias," but clinical evidence is still lacking. Buckley and col- leagues" describing a patient in whom in- tra-aortic balloon pumping was used for cardiogenic shock, mentioned that previous- ly recurrent ventricular tachycardia-fibrilla- tion was controlled during the subsequent hour; however, the long-term course of that patient was not described. In patients with the opposite clinical situation, i.e., cardio- genic shock secondary to ventricular tachy- arrhythmia, Dunkman," Mundth,"" and their associates found intra-aortic balloon pumping ineffective and subjected the pa- tients to emergency infarctectomy with good results. In 3 of our patients without cardio- genic shock, intra-aortic balloon pumping proved ineffective in controlling the ven- tricular arrhythmia.
Several surgical techniques have been advanced for managing life-threatening ar- rhythmias refractory to or not well con- trolled by antiarrhythmic agents in patients with ischemic heart disease. These include aneurysmectomy or scar resectionv" and, more recently, myocardial revascularization via saphenous vein bypass grafts between
Volume 67
Number 5
May, 1974
the aorta and the coronary arteries," some- times in combination with aneurysmectomy or intarctectomy." In most instances in which surgical resection has been employed, the patients had already survived the acute stage of myocardial infarction. In some re- cent reports, however, these operations were performed during the acute stage, and the most frequent pathology found has been left ventricular aneurysm. I", 20 In patients without a clear-cut aneurysm, definite guide- lines regarding infarctectomy are not avail- able." In the 2 patients whom we operated upon, the extent of myocardium requiring resection was too large to be compatible with life. Common anatomic findings in these 2 patients were (I) severe two-vessel coronary artery disease in 1 patient and three-vessel disease in the other, with com- plete proximal occlusion of the left anterior descending coronary artery in both, and (2) severe left ventricular dysfunction, with loss of motion of at least two thirds of the left ventricular wall including the apex, and ejection fractions of less than 25 per cent. On dividing the ventriculograms into six segments, as suggested by Sanders and his associates,' we found three or more akinetic segments in both patients. This has been shown to be a poor prognostic sign for survival after coronary artery revascular- ization for patients in cardiogenic shock." Postmortem examination in the third pa- tient also showed severe triple-vessel dis- ease with complete occlusion of the left anterior descending coronary artery and severe myocardial damage involving two thirds of the left ventricular wall and inter- ventricular septum. The cardiac catheteri- zation and postmortem findings in Patient 4 in this series were similar to those noted in the other 3 patients. All 4 of these patients had massive anteroseptal myocardial infarc- tions. All 4 had lost more than 50 per cent of the left ventricular mass. However, none of these 4 patients had a sizable localized left ventricular aneurysm.
Whether or not most patients who have serious, intractable ventricular arrhythmias in this setting will have anatomic patterns
Intractable tachycardia after infarction 823
similar to those of our 4 patients remains to be determined. The development of a means of identifying the ventricular site of origin and/or the electrophysiologic mecha- nism of such ventricular arrhythmias at the time of catheterization or surgery would potentially be of great benefit.
The number of cases reported here is small. However, review of these cases sug- gests that, when intractable and almost con- tinuous ventricular tachycardia occurs rela- tively late in the course of acute myocardial infarction and is associated with a severe degree of coronary disease and myocardial damage, the patients are not likely to be benefited by intra-aortic balloon pumping or emergency surgical intervention.
Summary
Four cases are reported in which fatal, intractable ventricular tachycardia de- veloped relatively late during hospital con- valescence from acute myocardial infarc- tion. All 4 cases were refractory to the usual modes of therapy, requiring multiple frequent ventricular defibrillation. Mechani- cal circulatory assistance in the form of Avco intra-aortic balloon pumping proved ineffective in the control of these ar- rhythmias. Cardiac catheterization, per- formed in 3 of the patients during the acute stage, and postmortem examination in the fourth revealed two common findings: (1) complete occlusion of the left anterior de- scending coronary artery near its origin and diffuse severe obstruction of the cir- cumflex; (2) severe myocardial disease with infarcted areas involving at least two thirds of the anterior wall. In addition, 3 of the patients had total occlusion of the right coronary artery. Angiography demonstrated severe left ventricular dysfunction, with ejection fractions under 25 per cent in 3 of the patients. An attempt to provide myo- cardial revascularization with infarct plica- tion proved ineffective in 1 patient. In an- other patient, infarctectomy was effective in preventing further episodes of ventricular tachycardia, but that patient subsequently died with a low cardiac output syndrome.
8 2 4 Sehapayak et al.
These findings suggest that the development of recurrent ventricular tachycardia late in the course of recovery from an acute myo- cardial infarction is an ominous prognostic sign in patients with the coronary and ven- tricular anatomy described herein. Treat- ment by either circulatory assistance or sur- gical intervention may be unsuccessful.
REFERENCES
Lawrie, D. M., Higgins, M. R., Godman, M. 1., Oliver, M. F., Julian, D. G., and Donald, K. W.: Ventricular Fibrillation Complicating Acute Myocardial…
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