Catheterization and Cardiovascular Diagnosis 22:133-136 (1991)
Treatment of Congenital Coronary Arteriovenous Malformations With Micro-Particle Embolization Brian L. Strunk, MD, Grant B. Hieshima, MD, and Eugene P. Shafton, MD The successfultreatment of a symptomatic coronary arteriovenousmalformation(CAVM) by a percutaneous embolization technique with micro-particles is described. Objective evidence of ischemia and its subsequent disappearance after embolization is presented. The embolization technique and possible indications and contraindications are discussed. Key words: coronary arteriovenous malformation ablation, percutaneous embolization technique, micro-particles
INTRODUCTION
Congenital coronary arteriovenous malformations (CAVMs) were first described in 1865 [ 11. CAVMs arise more commonly from the right than the left coronary artery and may drain into the right ventricle, right atrium, pulmonary artery, coronary sinus, and superior vena cava. Possible complications from CAVMs include congestive heart failure secondary to large left to right shunts, endocarditis, aneurysmal dilatations of coronary arteries, and perhaps ischemia secondary to a “steal” phenomenon [2]. When felt to be clinically important, surgical repair of the CAVMs has been the procedure of choice [3]. In this report, we describe a new, non-surgical approach to a patient with bilateral CAVMs with clinical symptoms and objective evidence of coronary artery ischemia.
A CASE REPORT
On August 30, 1988, a 55 year-old man was evaluated for increasing exertional left arm and chest discomfort and decreasing exercise tolerance. There was no history of smoking or congenital heart disease. The cardiac exam revealed a paradoxically split second sound and no murmurs or gallops. The electrocardiogram had recently changed from normal to a left bundle branch block pattern. The chest x-ray was normal and the total cholesterol was 184 with an HDL of 27. The patient’s treadmill thallium showed reversible septa1 and inferior wall defects (Fig. 1A) with dyspnea but no associated angina. Cardiac catherterization on August 30, 1988, showed the following: 1 ) Normal hemodynamics. 2) An oxygen saturation step-up between the right atrium and pulmonary artery with a calculated left to right shunt of 1.3: 1. 3) The 0 1991 Wiley-Liss, Inc.
coronary arteriogram showed the CAVMs arising from the proximal left anterior descending and right coronary arteries and draining into the main pulmonary artery (Fig. 2). The coronary arteries were otherwise normal. After a thorough discussion with the patient, we proceeded with embolization of the CAVM with micro-particles [4]. On October 4, 1988, a Tracker 18 infusion catheter was sequentially positioned into two vessels originating from the left anterior descending and one vessel originating from the right coronary artery. Polyvinyl alcohol foam particles 300-500 p m in diameter were mixed with contrast and slowly infused over 15-30 sec into each of the three vessels supplying the CAVMs (Fig. 3). The injections were administered slowly and as far into each vessel as possible so as to minimize the chance of any reflux into the epicardial coronary artery vessels (Fig. 2). After the CAVM was successfully embolized, the catheters were withdrawn and the patient was observed for 24 h and discharged on October 5 , 1988. A repeat treadmill thallium on October 10, 1988, revealed no reversible ischemia and no new defects from any inadvertent coronary artery embolization (Fig. 1B). The patient underwent follow-up coronary arteriography on December 7, 1988. There was continued obliteration of the CAVMs arising from the three embolized branches originating from the left anterior descending and right coronary arteries. However there was an interval increase in size of a smaller vessel originating more dis-
From the Department of Medicine, University of California, San Francisco. Received May 14, 1990; revision accepted September 27, 1990. Address reprint requests to Brian L. Strunk, M.D., Suite 607, 350 Parnassus Avenue, San Francisco, CA 941 17.
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Fig. 1. A short-axis SPECT image of the treadmill thallium before embolization (left) and after embolization (right). Before embolization there is ischemia in the interventricular septum extending into the inferior wall which redistributes four hours later. After embolization reversible ischemia is no longer seen.
tally in the left anterior descending coronary artery, allowing a small amount of dye to enter the main pulmonary artery. Follow-up interview of the patient on February 1 , 1990, revealed continued clinical improvement with improved exercise tolerance and no return of his exertional chest discomfort. DISCUSSION
CAVMs need to be subdivided into those cases where the drainage from the arterial to the venous system involves only large-caliber vessels, coronary arteriovenous fistula; and into those which involve arterial venous malformations with small intermediary vessels. Our case report had an arteriovenous malformation which allowed us to use polyvinyl alcohol particles ranging from 300500 p m which wedged into the small vessel portion of the arteriovenous malformation and caused the thrombosis and closure of the left-to-right shunt. If the CAVM in our case had been a true fistula, we would not have been able to use small particulate matter to effect a closure of the shunt. Our technique then can only be used in those CAVMs that have a capillary bed intervening between the arterial and venous system. We chose to use 300-500 pm-sized particles to close the CAVMs for several reasons. If there was reflux of these particles into the native coronary artery circulation, we would be able to terminate the procedure without occluding large epicardial vessels. Detachable balloons or coils were not necessary since our case had small intermediary vessels between the coronary arteries and pulmonary artery circuit. Liquid glue, while having the advantage of perhaps being more permanent than polyvinyl alcohol particles in occluding the malformation,
has the potential for more serious sequellae if the glue refluxes into the native coronary artery circulation [4]. We were prepared to repeat this embolization procedure at a later time if the patient developed both symptoms and objective evidence for recanalization, but so far after 18 mo the patient is still clinically asymptomatic. There is little controversy for closing a CAVM that has resulted in a hemodynamically significant left-to-right shunt leading to congestive heart failure or pulmonary hypertension [2], However, the indications for closing a CAVM because of coronary ischemia are more controversial. There are very few if any well-documented cases of CAVMs causing ischemia. Most case reports describe chest discomfort without EKG or nuclear confirmation of ischemia. Some case reports describe closure of a CAVM along with revascularization of fixed atherosclerotic cardiovascular disease, either surgically or with angioplasty. Our case report is unique in that there was no co-existing coronary artery disease and there was treadmill thallium evidence for ischemia prior to the closure of the CAVM and treadmill thallium evidence of improvement post embolization of the CAVM. Our patient has been followed for the past 18 mo and has remained clinically improved with no further chest discomfort and with improved exercise tolerance. One possible disadvantage to the embolization technique, by either micro-particles or detachable balloons or coils, is the enlargement of previously small vessels supplying the CAVM as seen in our follow-up angiogram of the left anterior descending coronary artery. In time further increase in size of these branches could result in the return of a clinically significant left-to-right shunt. It is because of this possibility that the preferred surgical technique now employed is closure of the venous entrance of
Micro-Particle Embolization
Fig. 2. A: Shows the left coronary artery injection with the coronary artery venous malformations (CAVMs) (arrow) arising from two sites from the left anterior descending coronary artery. B: Shows selective embolization of the proximal left anterior descending site. C: Shows selective embolization of the distal left anterior descending site. D: Shows a repeat left cor-
135
onary artery injection after embolization with obliteration of that portion of the CAVM arising from the left anterior descending coronary artery. E: Shows the right coronary artery injection filling the CAVM (arrow). F: Shows selective embolization of the right coronary artery origin of the CAVM.
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G
Fig. 3. A picture of the Tracker 18 infusion catheter and the polyvinyl alcohol form particles, 300-500 pm in diameter.
Fig. 2G: Shows repeat right coronary artery injection after obliteration of the CAVM originating from the right coronary artery.
REFERENCES
the CAVM into the pulmonary artery by patching from within the pulmonary artery, rather than by ligating the arterial branches supplying the CAVM. Treatment of this rare condition should be reserved for those cases with well-documented evidence of ischemia, since there is a morbidity and mortality with both surgical and non-surgical closure of a CAVM [ 5 ] . A recent report describing dislodgement of a detachable balloon during an attempt at closure of a CAVM is a case in point [61. Last, but not least, this case report demonstrates the benefits of cooperation between interventional radiologists and cardiologists. The technique used in this case was pioneered by interventional radiologists and in the spirit of cooperation used by interventional cardiologists for the benefit of our patient.
2,
3. 4.
5.
6.
Krause W: Uber den Ursprung einer Akzessorischen A. Coronaria ans der A. Pulmonali. Ration Med 24:225, 1865. Liberthson RR: Sagar K, Berkoben JP, Weintraub RM, Levine FH: Congenital coronary arteriovenous fistula. Report of 13 patients, review of the literature and delineation of management. Circulation 59:849- 854, 1979. Lowe JE, Aldham HN, Sabiston DC: Surgical management of congenital coronary artery fistulas. Ann Surg 194:373-380, 1981. Habach VV, Higashida RT, Hieshima GB: Interventional neuroradiology. Am Radio1 153:467-476, 1989. Hobbs RE, Millit HD, Raghavan PV, Moodie DS, Sheldon WC: Coronary artery fistulae: A 10 year review. Cleve Clin Q 49:191197, 1982. Meier B: Coronary occlusion after failed closure of coronaro-pulmonary fistula with detachable balloon. Cathet Cardiovasc Diagn 18:237-239, 1989.
Treatment of Congenital Coronary Arteriovenous Malformations With Micro-Particle Embolization Brian L. Strunk, MD, Grant B. Hieshima, MD, and Eugene P. Shafton, MD The successfultreatment of a symptomatic coronary arteriovenousmalformation(CAVM) by a percutaneous embolization technique with micro-particles is described. Objective evidence of ischemia and its subsequent disappearance after embolization is presented. The embolization technique and possible indications and contraindications are discussed. Key words: coronary arteriovenous malformation ablation, percutaneous embolization technique, micro-particles
INTRODUCTION
Congenital coronary arteriovenous malformations (CAVMs) were first described in 1865 [ 11. CAVMs arise more commonly from the right than the left coronary artery and may drain into the right ventricle, right atrium, pulmonary artery, coronary sinus, and superior vena cava. Possible complications from CAVMs include congestive heart failure secondary to large left to right shunts, endocarditis, aneurysmal dilatations of coronary arteries, and perhaps ischemia secondary to a “steal” phenomenon [2]. When felt to be clinically important, surgical repair of the CAVMs has been the procedure of choice [3]. In this report, we describe a new, non-surgical approach to a patient with bilateral CAVMs with clinical symptoms and objective evidence of coronary artery ischemia.
A CASE REPORT
On August 30, 1988, a 55 year-old man was evaluated for increasing exertional left arm and chest discomfort and decreasing exercise tolerance. There was no history of smoking or congenital heart disease. The cardiac exam revealed a paradoxically split second sound and no murmurs or gallops. The electrocardiogram had recently changed from normal to a left bundle branch block pattern. The chest x-ray was normal and the total cholesterol was 184 with an HDL of 27. The patient’s treadmill thallium showed reversible septa1 and inferior wall defects (Fig. 1A) with dyspnea but no associated angina. Cardiac catherterization on August 30, 1988, showed the following: 1 ) Normal hemodynamics. 2) An oxygen saturation step-up between the right atrium and pulmonary artery with a calculated left to right shunt of 1.3: 1. 3) The 0 1991 Wiley-Liss, Inc.
coronary arteriogram showed the CAVMs arising from the proximal left anterior descending and right coronary arteries and draining into the main pulmonary artery (Fig. 2). The coronary arteries were otherwise normal. After a thorough discussion with the patient, we proceeded with embolization of the CAVM with micro-particles [4]. On October 4, 1988, a Tracker 18 infusion catheter was sequentially positioned into two vessels originating from the left anterior descending and one vessel originating from the right coronary artery. Polyvinyl alcohol foam particles 300-500 p m in diameter were mixed with contrast and slowly infused over 15-30 sec into each of the three vessels supplying the CAVMs (Fig. 3). The injections were administered slowly and as far into each vessel as possible so as to minimize the chance of any reflux into the epicardial coronary artery vessels (Fig. 2). After the CAVM was successfully embolized, the catheters were withdrawn and the patient was observed for 24 h and discharged on October 5 , 1988. A repeat treadmill thallium on October 10, 1988, revealed no reversible ischemia and no new defects from any inadvertent coronary artery embolization (Fig. 1B). The patient underwent follow-up coronary arteriography on December 7, 1988. There was continued obliteration of the CAVMs arising from the three embolized branches originating from the left anterior descending and right coronary arteries. However there was an interval increase in size of a smaller vessel originating more dis-
From the Department of Medicine, University of California, San Francisco. Received May 14, 1990; revision accepted September 27, 1990. Address reprint requests to Brian L. Strunk, M.D., Suite 607, 350 Parnassus Avenue, San Francisco, CA 941 17.
134
Strunk et al.
CORONAL 9/2/88
Stress
Redist
CORONAL 10/10/88
Stress
Redist
Fig. 1. A short-axis SPECT image of the treadmill thallium before embolization (left) and after embolization (right). Before embolization there is ischemia in the interventricular septum extending into the inferior wall which redistributes four hours later. After embolization reversible ischemia is no longer seen.
tally in the left anterior descending coronary artery, allowing a small amount of dye to enter the main pulmonary artery. Follow-up interview of the patient on February 1 , 1990, revealed continued clinical improvement with improved exercise tolerance and no return of his exertional chest discomfort. DISCUSSION
CAVMs need to be subdivided into those cases where the drainage from the arterial to the venous system involves only large-caliber vessels, coronary arteriovenous fistula; and into those which involve arterial venous malformations with small intermediary vessels. Our case report had an arteriovenous malformation which allowed us to use polyvinyl alcohol particles ranging from 300500 p m which wedged into the small vessel portion of the arteriovenous malformation and caused the thrombosis and closure of the left-to-right shunt. If the CAVM in our case had been a true fistula, we would not have been able to use small particulate matter to effect a closure of the shunt. Our technique then can only be used in those CAVMs that have a capillary bed intervening between the arterial and venous system. We chose to use 300-500 pm-sized particles to close the CAVMs for several reasons. If there was reflux of these particles into the native coronary artery circulation, we would be able to terminate the procedure without occluding large epicardial vessels. Detachable balloons or coils were not necessary since our case had small intermediary vessels between the coronary arteries and pulmonary artery circuit. Liquid glue, while having the advantage of perhaps being more permanent than polyvinyl alcohol particles in occluding the malformation,
has the potential for more serious sequellae if the glue refluxes into the native coronary artery circulation [4]. We were prepared to repeat this embolization procedure at a later time if the patient developed both symptoms and objective evidence for recanalization, but so far after 18 mo the patient is still clinically asymptomatic. There is little controversy for closing a CAVM that has resulted in a hemodynamically significant left-to-right shunt leading to congestive heart failure or pulmonary hypertension [2], However, the indications for closing a CAVM because of coronary ischemia are more controversial. There are very few if any well-documented cases of CAVMs causing ischemia. Most case reports describe chest discomfort without EKG or nuclear confirmation of ischemia. Some case reports describe closure of a CAVM along with revascularization of fixed atherosclerotic cardiovascular disease, either surgically or with angioplasty. Our case report is unique in that there was no co-existing coronary artery disease and there was treadmill thallium evidence for ischemia prior to the closure of the CAVM and treadmill thallium evidence of improvement post embolization of the CAVM. Our patient has been followed for the past 18 mo and has remained clinically improved with no further chest discomfort and with improved exercise tolerance. One possible disadvantage to the embolization technique, by either micro-particles or detachable balloons or coils, is the enlargement of previously small vessels supplying the CAVM as seen in our follow-up angiogram of the left anterior descending coronary artery. In time further increase in size of these branches could result in the return of a clinically significant left-to-right shunt. It is because of this possibility that the preferred surgical technique now employed is closure of the venous entrance of
Micro-Particle Embolization
Fig. 2. A: Shows the left coronary artery injection with the coronary artery venous malformations (CAVMs) (arrow) arising from two sites from the left anterior descending coronary artery. B: Shows selective embolization of the proximal left anterior descending site. C: Shows selective embolization of the distal left anterior descending site. D: Shows a repeat left cor-
135
onary artery injection after embolization with obliteration of that portion of the CAVM arising from the left anterior descending coronary artery. E: Shows the right coronary artery injection filling the CAVM (arrow). F: Shows selective embolization of the right coronary artery origin of the CAVM.
136
Strunk et al.
G
Fig. 3. A picture of the Tracker 18 infusion catheter and the polyvinyl alcohol form particles, 300-500 pm in diameter.
Fig. 2G: Shows repeat right coronary artery injection after obliteration of the CAVM originating from the right coronary artery.
REFERENCES
the CAVM into the pulmonary artery by patching from within the pulmonary artery, rather than by ligating the arterial branches supplying the CAVM. Treatment of this rare condition should be reserved for those cases with well-documented evidence of ischemia, since there is a morbidity and mortality with both surgical and non-surgical closure of a CAVM [ 5 ] . A recent report describing dislodgement of a detachable balloon during an attempt at closure of a CAVM is a case in point [61. Last, but not least, this case report demonstrates the benefits of cooperation between interventional radiologists and cardiologists. The technique used in this case was pioneered by interventional radiologists and in the spirit of cooperation used by interventional cardiologists for the benefit of our patient.
2,
3. 4.
5.
6.
Krause W: Uber den Ursprung einer Akzessorischen A. Coronaria ans der A. Pulmonali. Ration Med 24:225, 1865. Liberthson RR: Sagar K, Berkoben JP, Weintraub RM, Levine FH: Congenital coronary arteriovenous fistula. Report of 13 patients, review of the literature and delineation of management. Circulation 59:849- 854, 1979. Lowe JE, Aldham HN, Sabiston DC: Surgical management of congenital coronary artery fistulas. Ann Surg 194:373-380, 1981. Habach VV, Higashida RT, Hieshima GB: Interventional neuroradiology. Am Radio1 153:467-476, 1989. Hobbs RE, Millit HD, Raghavan PV, Moodie DS, Sheldon WC: Coronary artery fistulae: A 10 year review. Cleve Clin Q 49:191197, 1982. Meier B: Coronary occlusion after failed closure of coronaro-pulmonary fistula with detachable balloon. Cathet Cardiovasc Diagn 18:237-239, 1989.
