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Pulmonary arteriovenous malformations: Therapeutic options
Pulmonary Arteriovenous Malformations: Therapeutic Options John D. Puskas, MD, Mark S. Allen, MD, Ashby C. Moncure, MD, John C. Wain, Jr, MD, Alan D. Hilgenberg, MD, Cameron Wright, MD, Hermes C. Grillo, MD, and Douglas J. Mathisen, MD General Thoracic Surgical Unit, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
We have treated 21 patients (13 female, 8 male) with pulmonary arteriovenous malformations (PAVMs). Mean age at diagnosis was 37.5 years (range, 15 to 72 years). Presenting symptoms included dyspnea on exertion (67%), hereditary hemorrhagic telangiectasia (57%), and major neurologic events (33%). In our early experience, 8 patients had no specific treatment; their case histories illustrate the major neurologic complications of untreated PAVMs. Nine patients (8 primarily, 1 after recurrence) underwent conservative surgical excision; 4 had lobectomy, and 5 had segmentectomy or subsegmental excision. One patient underwent staged bilateral thoracotomies for multiple bilateral lesions. The arterial oxygen tension was found to increase after excision of large or solitary PAVMs. All surgically treated patients were relieved of dyspnea, and none had postoperative
I
n 1897, Churton [l] first described a pulmonary arteriovenous malformation (PAVM) in a 12-year-old boy. There have since been many other reports [2-61. Clinical presentation of PAVMs ranges from an incidental finding on a chest roentgenogram in an asymptomatic patient to polycythemia, cyanosis, congestive heart failure, and major neurologic deficits caused by paradoxical embolism. There has been a clear association with hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber[R-0-W] syndrome) [7, 81. The first reported surgical intervention for PAVM was a pneumonectomy in 1940 by Shestone for a large centrally located lesion [9]. Since that successful surgical resection, conservatism has prevailed in the management of these patients. Lung-sparing procedures using local excision or segmentectomy are now preferred [6, 7, 101. Often patients with bilateral disease have not been considered surgical candidates because of the difficulties of bilateral thoracotomies, concern over pulmonary reserve, and the belief that complete resection of all lesions would be impossible. Nonetheless, staged bilateral thoracotomies have been performed to successfully treat multiple bilateral PAVMs [ll]. Angiographic embolization of PAVMs with metal coils Presented at the Twenty-ninth Annual Meeting of The Society of Thoracic Surgeons, San Antonio, TX, Jan 2527, 1993. Address reprint requests to Dr Mathisen, Thoracic Surgical Unit, Warren 11th Floor, Massachusetts General Hospital, Fruit St, Boston, MA 02114.
0 1993 by The Society of Thoracic Surgeons
recurrence of PAVMs or neurologic complications related to PAVMs. Five patients underwent balloon occlusion of PAVMs. Two patients chose to have solitary PAVMs occluded rather than undergo thoracotomy. One underwent surgical excision 5 years later, and the other required repeat balloon embolization 4 years later when recanalization of the PAVMs was documented. Three patients with numerous PAVMs received palliation with multiple balloon embolizations. The high incidence of associated major neurologic complications mandates aggressive treatment of PAVMs whenever feasible. Conservative surgical resection remains the treatment of choice. Balloon embolization offers an alternative therapy for patients who are poor surgical risks or those whose lesions are too numerous to resect. (Ann Tkorac Surg 1993;56:253-8)
was first reported by Porstmann [12] in 1977. Other studies [13, 141 of the use of detachable latex or silicone balloons soon followed. This technique adds another therapeutic option in managing patients with PAVM.
Material and Methods We reviewed the records of all 21 patients with documented PAVMs seen at Massachusetts General Hospital between 1964 and 1992. There were 13 female and 8 male patients with a mean age at the time of diagnosis of 37.5 years (range, 15 to 72 years). The angiogram or surgical specimen confirmed the diagnosis in 17 patients (81%). Four patients were diagnosed by plain chest roentgenography or tomography alone and did not undergo angiography or surgical resection. However, these patients had classic roentgenographic and physical findings. Follow-up (range, 1 to 28 years; median, 12 years) was obtained by direct patient contact for 17 of the 21 patients.
Symptoms and Signs Presenting symptoms and signs in the 21 patients are listed in Table 1. Dyspnea on exertion, present in 67% of patients, was by far the most common complaint. Twelve patients (57%) had R-0-W syndrome. Three of these 12 patients had documented cerebral arteriovenous malformations. Consistent with the natural history of untreated PAVMs [7, 15-17], 7 (33%) of our patients had major 0003-4975/93/$6.00
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Table 1. Presenting Signs and Symptoms of Pulmonary Arteriovenous Malformations in 21 Patients Sign or Symptolr
No. of Patients
Dyspnea on exertion Cutaneous telangiectasia(s) CNS symptoms Clubbing Cyanosis Bruit over PAVM Recurrent epistaxis Hemoptysis Asymptomatidno signs a
Table 3. Number and Location of Pulmonary Arteriovenous Malformations
14 10 7" 7 6 6
67 48 33 33
1
29 29 29 5
2
10
6
Variable Solitary PAVM Multiple unilateral PAVMs Multiple bilateral PAVMs Lower lobe location PAW
This excludes 4 patients with migraine only.
CNS = central nervous system; malformation.
PAVM
=
DisfribufionlLocafionof PAVMs Twelve patients had single PAVMs, 8 patients had multiple PAVMs bilaterally, and l patient had multiple PAVMs in a single lobe (Table 3). Of the 12 patients with R-0-W syndrome, 5 had a single PAVM and 7, multiple lesions. The lower lobes were the predominant location of PAVMs. Seventeen patients had at least one PAVM in a lower lobe. In patients with R-0-W syndrome with multiple PAVMs, more than 70% of lesions occurred in the lower lobes. Table 2. Central Nervous System Manifestations of Pulmonary Arteriovenous Malformations No. of Patients CNS Event
Total patients with CNS manifestations of PAVM
=
Present (n = 12 patients)
Absent (n = 9 patients)
Total (n = 21 patients)
5 1
7
12
0
1
6
2
8
11
6
17
pulmonary arteriovenous malformation.
pulmonary arteriovenous
neurologic findings as an initial symptom of PAVM (Table 2). Four other patients reported migraines as their only neurologic complaint. Routine admission chest roentgenography detected PAVMs in 2 asymptomatic patients with R-0-W syndrome. Tomography or angiography confirmed the diagnosis in both.
Transient ischemic attack Embolic CVA Brain abscess Seizure disorder Craniotomylneurosurgery CNS bleed due to cerebral AVM Migraines Bell's palsy
Rendu-Osler-WeberSyndrome
Percent (%)
Initial Presentation
Lifetime
5 4 3 4
3 1 1 1 1 0
1 (fatal)
5 1
8 1
7
7
3
CNS = central nervous system; AVM = arteriovenous malformation; PAVM = pulmonary arteriovenous CVA = cerebrovascular accident; malformation.
Results No Treatment Eight patients, seen between 1964 and 1978, had no treatment. Four of the 8 were first seen at a young age (range, 18 to 48 years) with minimal symptoms of mild dyspnea on exertion. Confirmatory studies (tomography or angiography) documented one or more PAVMs, and subsequently these patients were lost to follow-up. In another patient, a solitary PAVM was noted on a chest roentgenogram during admission for terminal cardiac failure at age 63 years. Three patients received no therapy for their PAVMs because of other medical conditions that were thought to contraindicate surgical resection of the PAVMs. Their case histories are summarized briefly and illustrate the major morbidity associated with the neurologic complications of untreated PAVMs. In 1964, a 48-year-old man with R-0-W syndrome had angiographic confirmation of four large bilateral PAVMs. Initially, no treatment was given. He was seen 9 years later with a left frontal brain abscess, which required craniotomy. He refused staged bilateral thoracotomies. Over the next 7 years, the patient was admitted three times with central nervous system complaints, including recurrent seizures and a major hemispheric stroke. PATIENT 1.
A 72-year-old woman with known R-0-W syndrome had angiographic documentation of a single PAVM and at least two cerebral arteriovenous malformations. She received no treatment because of advanced age and the presence of the cerebral lesions. She was admitted on multiple occasions for transient hemiparesis with aphasia and sustained a major stroke 10 years later.
PATIENT 2.
A 28-year-old woman without R-0-W syndrome was seen with a transient hemianopsia, right hemiparesis, and an abnormal chest roentgenogram. Pulmonary arteriogram revealed at least five basilar PAVMs bilaterally. No specific treatment was undertaken, and the symptoms spontaneously resolved. Nine years later, a PATIENT 3.
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Table 4. Surgical Management of Pulmonary Arteriovenous Malformations No. of PAVMs
Lobectomy
Multiple Segmentectomies
Segmentectomy
Subsegmental Excision
Solitary Multiple unilateral Multiple bilateral Total P A W S = pulmonary arteriovenous malformations.
second episode of transient hemiparesis occurred. The chest roentgenogram at that time was unchanged, and cerebral angiography showed no abnormality. No specific therapy was given. Twenty-two years later, she was seen with a left thalamic brain abscess. Stereotactic drainage of the brain abscess was performed, and the patient underwent a long and incomplete rehabilitation.
Surgical Resection Eight patients had primary surgical excision of their PAVMs, and a ninth patient underwent surgical excision after documented recurrence of a PAVM after balloon embolization therapy (Table 4). There was no postoperative morbidity or mortality. All patients have remained well without documented recurrence or growth of new PAVMs. Median follow-up is 12 years (range, 1 to 25 years). Three patients underwent segmentectomy for single unilateral PAVMs. Four patients underwent lobectomy: 2 for solitary PAVMs (both right middle lobe), 1for multiple PAVMs confined to the right lower lobe, and 1 for multiple large PAVMs in the right lower lobe, with multiple tiny PAVMs left elsewhere. All of these patients were relieved of their symptoms, and none had postoperative recurrence or enlargement of the PAVMs. There were no postoperative neurologic complications attributable to the PAVMs. One patient underwent staged bilateral thoracotomies for multiple bilateral lesions. The case history follows. A 17-year-old girl was seen with decreased exercise tolerance, fatigue, clubbing, and cyanosis of 4 years’ duration. She had a family history of hereditary hemorrhagic telangiectasia but had no cutaneous telangiectasias herself. A pulmonary angiogram showed PAVMs of the posterior segment of the right upper lobe, the medial basal segment of the right lower lobe, the anteromedial basal segment of the left lower lobe, and the lingula of the left upper lobe. She had a hematocrit of 0.48 and a calculated shunt fraction of 0.36. Pulmonary function studies were normal. Staged surgical procedures were planned because of her young age and the belief that the lesions were all amenable to surgical resection. At the first operation, she underwent posterior segmentectomy of the right upper lobe and medial basal segmentectomy of the right lower lobe. Arterial blood gas analysis was done before and after these resections (Table 5). The postoperative course was unremarkable. One year later PATIENT 4.
she underwent basal segmentectomy of the left lower lobe and multiple wedge resections of many smaller lesions on both the left upper and lower lobes. She had an uneventful recovery and has remained asymptomatic during 10 years of follow-up.
Balloon Occlusion of PAVMs Five patients underwent balloon occlusion of PAVMs. In 3 patients, multiple balloons were placed angiographically to occlude multiple PAVMs associated with R-0-W syndrome. One of them underwent multiple embolizations of numerous PAVMs with a total of six balloons; three of these balloons subsequently could not be found on follow-up chest roentgenograms. One patient had the largest of multiple PAVMs embolized with little improvement in pulmonary shunting. She ultimately died of hemorrhage from multiple cerebral arteriovenous malformations. The third patient had numerous PAVMs requiring multiple repeated balloon embolizations at another institution. He was admitted on two separate occasions to our institution with brain abscess and major stroke. Two patients, whose case histories follow, had a solitary PAVM occluded. One of them underwent surgical excision 5 years later and the other, repeat balloon embolization 4 years later after documented recanalization of the PAVM. PATIENT 5. A 35-year-old man without R-0-W syndrome was seen in 1981 with acute right hemiparesis and expressive aphasia. A carotid arteriogram documented an embolus to the middle cerebral artery. Chest roentgenography and pulmonary angiography demonstrated a solitary subpleural PAVM in the left lower lobe. The neurologic deficits resolved, and the patient chose to have balloon embolization rather than surgical excision. The large PAVM was occluded with a 2-mm Becton-Dickinson(Fair-
Table 5 . Results of Arterial Blood Gas Analysis in Patient 4 Oxygen Tension (mm Hg) Inspired Gas
Preop
RUL Segmentectomy
RLL Segmentectomy
Room air 100% oxygen
54 72
NA 104
176
NA = not available; lobe.
RLL = right lower lobe;
76 RUL
=
right upper
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field, NJ)detachable balloon (inflated to 8 mm in diameter), and angiography confirmed occlusion of the PAVM. A chest roentgenogram 4 months later showed stable position of the balloon and involution of the PAVM. Results of a lung scan at that time were consistent with occlusion of the PAVM. The patient was asymptomatic for 5 years after this procedure. In 1986, the balloon was not visible on routine surveillance chest roentgenogram. Pulmonary angiography confirmed recurrence of the PAVM. The patient opted for surgical resection. Feeder vessels of the solitary large PAVM were isolated and doubly ligated before cautery excision of the subpleural lesion. The patient did well postoperatively without recurrence of the PAVM on chest roentgenography or any neurologic complications during 6 years of follow-up. In 1986, a 42-year-old woman without R-0-W syndrome complained of migraines and fatigue. Chest roentgenography and angiography demonstrated a large solitary PAVM in the right lower lobe. Two balloons were placed in two large feeder vessels, and angiography confirmed occlusion of the PAVM. Four years later, she complained of vague neurologic deficits associated with the migraines. No balloons were visible on chest roentgenograms, and angiography documented recanalization of the PAVM. She underwent sequential embolization of the PAVM with both a metal coil and a ;siliconeballoon and has been in stable condition during 2 years of followUP. PATIENT 6.
Comment Pulmonary arteriovenous malformations are an uncommon clinical problem. The classic triad of dyspnea on exertion, cyanosis, and clubbing should ,alert the physician to the possibility of a PAVM, but it was unequivocally present in only 2 (10%) of our patients. Other signs and symptoms were more frequently seen (see Table 1). Pulmonary arteriovenous malformations are iisually congenital; however, there are reports of acquired PAVMs after infection [3], metastatic carcinoma [6], or trauma [5]. Consistent with other reports [3, 7, 81, hereditary hemorrhagic telangiectasia (R-0-W syndrome) was diagnosed in 12 (57%)of our patients. All patients with this syndrome should be screened for PAVMs by contrast computed tomographic scan. Paradoxical emboli may cause major neurologic deficits [16, 181, and central nervous system complaints may be the first manifestation of PAVM [15]. Seven of our patients presented with major neurologic findings. Brain abscess is a devastating complication of PAVM and occurred in 3 of our patients. The high incidence of associated major neurologic complications mandates aggressive treatment of PAVM whenever feasible. The goals of therapy for PAVM are twofold: to reduce or eliminate the pulmonary shunt and to prevent the devastating neurologic consequences of paradoxical embolism. All patients who had surgical resection were relieved of dyspnea, and none experienced further neurologic complications.
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There is an association between cerebral arteriovenous malformations and PAVMs, especially in patients with R-0-W syndrome [16]. Three of our patients had documented cerebral arteriovenous malformations. All patients with PAVMs should be screened for cerebral malformations by contrast computed tomography or magnetic resonance imaging. The chest roentgenogram often suggests the presence of a PAVM. If doubt exists about a mass on the chest roentgenogram, chest tomograms, computed tomograms, or pulmonary arteriograms will usually be diagnostic. Pulmonary arteriography should be done before surgical intervention to document the number and location of all lesions. Pulmonary arteriovenous malformations predominantly affect the lower lobes. In our series, more than 70% of all lesions were in the lower lobes and were equally distributed between the right and left lower lobes. These malformations are more often solitary than multiple [8]; 57% of our patients had a solitary PAVM. Bilateral lesions have been reported more commonly in patients with hereditary hemorrhagic telangiectasia (R-0-W syndrome) [5, 81. Of the 8 patients in our series with bilateral PAVMs, 6 had R-0-W syndrome. There has been some dispute about whether PAVMs enlarge with time [2, 41. One of 3 patients who had serial pulmonary arteriograms had documented enlargement of a PAVM. Although multiple residual tiny PAVMs may contribute to substantial pulmonary shunting after resection of dominant PAVMs, we have not documented growth of or embolic complications from these residual tiny lesions. We believe that if these lesions do enlarge over time [7], it is likely to be a very slow process. Careful surveillance of patients with such lesions is advised. Lung-conserving resection is optimal therapy for PAVMs. It guarantees successful elimination of the PAVM and has minimal morbidity and mortality. Segmentectomy or local excision is the procedure of choice whenever possible. Staged bilateral thoracotomies are a viable option in the otherwise healthy patient with bilateral disease [ l l ] . Therapeutic embolization of the pulmonary artery offers another treatment option. Metal coils were used initially [13], but detachable balloons, used alone or in combination with coils, have recently become more popular [8, 14, 191. Details of the technique are reported elsewhere [19]. Balloon embolization is a suitable alternative to surgical intervention in elderly patients, patients who are poor surgical risks, patients with multiple lesions in whom surgical excision would sacrifice excessive lung tissue, and patients who decline surgical intervention. Patients tolerate balloon embolization well, and complications are infrequently reported [8, 191. However, 1 of our patients sustained a pulmonary infarction and pleural effusion during staged placement of multiple balloons. This patient also had a transient episode of aphasia due to a thromboembolic event. The incidence of balloon migration at the time of angiographic placement is reported to be low [19, 201. Systemic embolization of balloons or thrombus during angiographic placement is a potentially
Ann Thorac Surg 1993;5625>8
catastrophic complication, as the balloon can embolize into any portion of the systemic circulation. Delayed deflation of balloons, as occurred in 3 of our patients (60% of those treated with balloon embolization), is also potentially dangerous. In 2 of these patients, angiography documented recanalization of solitary PAVMs 4 and 5 years after balloon occlusion. Reports of embolization therapy [19, 201 do not adequately document long-term follow-up with serial chest roentgenograms and oximetry to evaluate the incidence of delayed balloon deflation and recurrence of PAVMs. Simple ligation has been abandoned as a surgical procedure for PAVMs because of the difficulty of finding all feeder vessels and the high incidence of recanalization of PAVMs through tiny accessory vessels [7]. Also, balloon embolization simply occludes the afferent vessel or vessels to the PAVM and may be associated with a higher incidence of late recurrence than has been appreciated. Balloon embolization must be further evaluated by longterm follow-up and careful documentation of the risks of balloon migration, clot propagation, and recurrence of PAVMs.
References 1. Churton T. Multiple aneurysms of pulmonary artery. Br Med J 1897;1:1223. 2. Gomes MR, Bernatz PE, Dines DE. Pulmonary arteriovenous fistulas. Ann Thorac Surg 1969;7:582-3. 3. Mansour KA, Hatcher CR Jr, Logan WD Jr, Abbott OA. Pulmonary arteriovenous fistula. Am Surg 1971;37:203-8. 4. Dines DE, Arms RA, Bernatz PE, Gomes MR. Pulmonary arteriovenous fistulas. Mayo Clin Proc 1974;49:460-5. 5. Dines DE, Seward JB, Bernatz PE. Pulmonary arteriovenous fistulas. Mayo Clin Proc 1983;58:176-81. 6. Prager RL, Laws KH, Bender HW Jr. Arteriovenous fistula of the lung. Ann Thorac Surg 1983;36:231-9. 7. Bosher LH, Blake AD, Byrd BR. An analysis of the pathologic anatomy of pulmonary arteriovenous aneurysms with par-
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ticular reference to the applicability of local excision. Surgery 1959;45:91-104. 8. Burke CM, Safai C, Nelson DP, Raffin TA. Pulmonary arteriovenous malformations: a critical update. Am Rev Respir Dis 1986;134:334-9. 9. Hepburn J, Dauphinee JA. Successful removal of hemangioma of the lung followed by the disappearance of polycythemia. Am J Med Sci 1942;204:681-5. 10. Parker EF, Stallworth JM. Arteriovenous fistula of the lung treated by dissection and excision without pulmonary excision. Surgery 1952;32:31-8. 11. Brown SE, Wright PW, Renner JW, Riker JB. Staged bilateral thoracotomies for multiple pulmonary arteriovenous malformations complicating hereditary hemorrhagic telangiectasia. J Thorac Cardiovasc Surg 1982;83:285-9. 12. Porstmann W. Therapeutic embolization of arteriovenous pulmonary fistula by catheter technique. In: Kelop 0, ed. Current concepts in pediatric radiology. Berlin: Springer, 197723-31. 13. Taylor BG, Cockerill EM, Manfredi F, Klatte EC. Therapeutic embolization of the pulmonary artery in pulmonary arteriovenous fistula. Am J Med 1978;64:360-5. 14. Terry PB, Barth KH, Kaufman SL, White RI. Balloon embolization for treatment of pulmonary arteriovenous fistulas. N Engl J Med 1980;302:1189-90. 15. Momma F, Ohara S, Ohyama T, Mot0 A, Okada H, Harada H. Brain abscess associated with congenital pulmonary arteriovenous fistula. Surg Neurol 1990;34:439-41. 16. Roman G, Fisher M, Per1 DP, Poser CM. Neurological manifestations of hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease): report of 2 cases and review of the literature. Ann Neurol 1978;4:130-44. 17. Sluiter-Eringa H, Orie NGM, Sluiter HJ. Pulmonary arteriovenous fistula: diagnosis and prognosis in noncompliant patients. Am Rev Respir Dis 1969;100:177-84. 18. Press OW, Ramsey PG. Central nervous system infections associated with hereditary hemorrhagic telangiectasia. Am J Med 1984;7786-92. 19. White RI, Lynch-Nyhan A, Terry P, et al. Pulmonary arteriovenous malformations: techniques and long-term outcome of embolotherapy. Radiology 1988;169:663-9. 20. Hughes JMB, Allison DJ. Pulmonary arteriovenous malformations: the radiologist replaces the surgeon. Clin Radio1 1990;41:297-8.
DISCUSSION DR DENTON A. COOLEY (Houston, TX): Is anyone curious about where those balloons are now that were not identified? DR JOSEPH S. McLAUGHLIN (Baltimore, MD): I congratulate Dr Puskas, Dr Mathisen, and their associates on this excellent report and particularly Dr Puskas for his excellent presentation. This is not a large series; it is not even a particularly unique series; but it is a very important series because it revisits a subject that requires reevaluation. An isolated, small arteriovenous malformation with a single vessel leading to it is easily treated either by embolization of the vessel or by surgical resection of the lesion. Both techniques give very good results. This is not the case for large arteriovenous malformations with multiple arteries. On examination of a cut section, one can see the sinusoids, which allow embolization to occur from the systemic circulation through the sinusoids out to the systemic circulation. When this happens, all too often emboli reach the brain and
produce large areas of necrosis. These large arteriovenous malformations are not well treated by embolization. I have three questions for Dr Puskas and Dr Mathisen. First, they recommend the use of bilateral or staged bilateral thoracotomies to treat patients who have multiple fistulas bilaterally. I wonder if they have given any thought to the use of a sternotomy incision to attack both lungs at the same time. Second, they talked about complications of the procedure itself, which are mostly related to Rendu-Osler-Weber syndrome. What about the complications that occur from the operation per se in this kind of situation? Third, and this is really the crux of the matter, a man named White, who was previously in Baltimore and who, I believe, is now chief of radiology at Yale, has presented nearly 300 of these fistulas treated by embolization either with balloons or with metal coils. If memory serves me, he has had only two major complications in these patients. This is in marked contrast to the data presented. I would appreciate the authors’ comments on why
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there is this marked discrepancy between what has occurred with Dr White’s series of embolizationand what has happened in their series.
DR PUSKAS: I thank the discussants for their remarks. In
response to Dr Cooley’s important question, we do not know where the balloon is in the 1 patient who underwent balloon therapy at our institution and subsequently had surgical intervention. The surgical specimen did not contain the balloon. There was no evidence that it had migrated to the central nervous system, and the patient had no particular symptoms that would lead us to know where the balloon had migrated. In response to Dr McLaughlin’sfirst question about the role of sternotomy in the management of bilateral pulmonary arteriovenous malformations, in the patient in whom we resected bilateral lesions, we chose bilateral staged thoracotomies because the lesions were typically posterior and in the lower lobes. This is, in fact, the most common location for these lesions, and it is the area of pulmonary parenchyma most awkward to resect through a sternotomy. However, for patients who have more anterior or superior lesions that could be easily resected through a stemotomy, we think a stemotomy would serve well. With respect to the surgical complications in our series, we operated on 9 patients and had no surgical complications after routine thoracotomies and parenchyma-conserving resections. In response to Dr McLaughlin’s remarks about Dr Robert
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White’s radiologic series from both Johns Hopkins and now Yale University Medical Center, Dr White published in 1988a series of 276 pulmonary arteriovenous malformations that were embolized in 76 patients. In his series, 90% of patients had RenduOsler-Weber syndrome, and he was dealing with multiple bilateral arteriovenous malformations in most of the patients. He had two early complications related to inadvertent migration of balloons during their angiographic placement. One of the balloons was located in the hepatic artery and one, in the hypogastric artery of those 2 patients. Ten percent of his patients had pleurisy and pleural effusions, and there was a major thrombophlebitis in 1 patient, which required long-term anticoagulation. Those were the complications related to the angiographic procedure itself. Only 16 of the 76 patients had repeat angiography. Those patients underwent repeat embolization of the very numerous pulmonary arteriovenous malformations. Dr White has very limited follow-up of those patients, as they are referred to him from all over the world. In conversations with me, he has said that less than 20% have accurate long-term follow-up in his data at Yale. Although he states that there have been no complications from migration of balloons, he does acknowledge that after balloon therapy several patients have had strokes or brain abscesses. None of the patients treated surgically in our smaller series sustained either a surgical or a postoperative neurologic complication.
We have treated 21 patients (13 female, 8 male) with pulmonary arteriovenous malformations (PAVMs). Mean age at diagnosis was 37.5 years (range, 15 to 72 years). Presenting symptoms included dyspnea on exertion (67%), hereditary hemorrhagic telangiectasia (57%), and major neurologic events (33%). In our early experience, 8 patients had no specific treatment; their case histories illustrate the major neurologic complications of untreated PAVMs. Nine patients (8 primarily, 1 after recurrence) underwent conservative surgical excision; 4 had lobectomy, and 5 had segmentectomy or subsegmental excision. One patient underwent staged bilateral thoracotomies for multiple bilateral lesions. The arterial oxygen tension was found to increase after excision of large or solitary PAVMs. All surgically treated patients were relieved of dyspnea, and none had postoperative
I
n 1897, Churton [l] first described a pulmonary arteriovenous malformation (PAVM) in a 12-year-old boy. There have since been many other reports [2-61. Clinical presentation of PAVMs ranges from an incidental finding on a chest roentgenogram in an asymptomatic patient to polycythemia, cyanosis, congestive heart failure, and major neurologic deficits caused by paradoxical embolism. There has been a clear association with hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber[R-0-W] syndrome) [7, 81. The first reported surgical intervention for PAVM was a pneumonectomy in 1940 by Shestone for a large centrally located lesion [9]. Since that successful surgical resection, conservatism has prevailed in the management of these patients. Lung-sparing procedures using local excision or segmentectomy are now preferred [6, 7, 101. Often patients with bilateral disease have not been considered surgical candidates because of the difficulties of bilateral thoracotomies, concern over pulmonary reserve, and the belief that complete resection of all lesions would be impossible. Nonetheless, staged bilateral thoracotomies have been performed to successfully treat multiple bilateral PAVMs [ll]. Angiographic embolization of PAVMs with metal coils Presented at the Twenty-ninth Annual Meeting of The Society of Thoracic Surgeons, San Antonio, TX, Jan 2527, 1993. Address reprint requests to Dr Mathisen, Thoracic Surgical Unit, Warren 11th Floor, Massachusetts General Hospital, Fruit St, Boston, MA 02114.
0 1993 by The Society of Thoracic Surgeons
recurrence of PAVMs or neurologic complications related to PAVMs. Five patients underwent balloon occlusion of PAVMs. Two patients chose to have solitary PAVMs occluded rather than undergo thoracotomy. One underwent surgical excision 5 years later, and the other required repeat balloon embolization 4 years later when recanalization of the PAVMs was documented. Three patients with numerous PAVMs received palliation with multiple balloon embolizations. The high incidence of associated major neurologic complications mandates aggressive treatment of PAVMs whenever feasible. Conservative surgical resection remains the treatment of choice. Balloon embolization offers an alternative therapy for patients who are poor surgical risks or those whose lesions are too numerous to resect. (Ann Tkorac Surg 1993;56:253-8)
was first reported by Porstmann [12] in 1977. Other studies [13, 141 of the use of detachable latex or silicone balloons soon followed. This technique adds another therapeutic option in managing patients with PAVM.
Material and Methods We reviewed the records of all 21 patients with documented PAVMs seen at Massachusetts General Hospital between 1964 and 1992. There were 13 female and 8 male patients with a mean age at the time of diagnosis of 37.5 years (range, 15 to 72 years). The angiogram or surgical specimen confirmed the diagnosis in 17 patients (81%). Four patients were diagnosed by plain chest roentgenography or tomography alone and did not undergo angiography or surgical resection. However, these patients had classic roentgenographic and physical findings. Follow-up (range, 1 to 28 years; median, 12 years) was obtained by direct patient contact for 17 of the 21 patients.
Symptoms and Signs Presenting symptoms and signs in the 21 patients are listed in Table 1. Dyspnea on exertion, present in 67% of patients, was by far the most common complaint. Twelve patients (57%) had R-0-W syndrome. Three of these 12 patients had documented cerebral arteriovenous malformations. Consistent with the natural history of untreated PAVMs [7, 15-17], 7 (33%) of our patients had major 0003-4975/93/$6.00
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Table 1. Presenting Signs and Symptoms of Pulmonary Arteriovenous Malformations in 21 Patients Sign or Symptolr
No. of Patients
Dyspnea on exertion Cutaneous telangiectasia(s) CNS symptoms Clubbing Cyanosis Bruit over PAVM Recurrent epistaxis Hemoptysis Asymptomatidno signs a
Table 3. Number and Location of Pulmonary Arteriovenous Malformations
14 10 7" 7 6 6
67 48 33 33
1
29 29 29 5
2
10
6
Variable Solitary PAVM Multiple unilateral PAVMs Multiple bilateral PAVMs Lower lobe location PAW
This excludes 4 patients with migraine only.
CNS = central nervous system; malformation.
PAVM
=
DisfribufionlLocafionof PAVMs Twelve patients had single PAVMs, 8 patients had multiple PAVMs bilaterally, and l patient had multiple PAVMs in a single lobe (Table 3). Of the 12 patients with R-0-W syndrome, 5 had a single PAVM and 7, multiple lesions. The lower lobes were the predominant location of PAVMs. Seventeen patients had at least one PAVM in a lower lobe. In patients with R-0-W syndrome with multiple PAVMs, more than 70% of lesions occurred in the lower lobes. Table 2. Central Nervous System Manifestations of Pulmonary Arteriovenous Malformations No. of Patients CNS Event
Total patients with CNS manifestations of PAVM
=
Present (n = 12 patients)
Absent (n = 9 patients)
Total (n = 21 patients)
5 1
7
12
0
1
6
2
8
11
6
17
pulmonary arteriovenous malformation.
pulmonary arteriovenous
neurologic findings as an initial symptom of PAVM (Table 2). Four other patients reported migraines as their only neurologic complaint. Routine admission chest roentgenography detected PAVMs in 2 asymptomatic patients with R-0-W syndrome. Tomography or angiography confirmed the diagnosis in both.
Transient ischemic attack Embolic CVA Brain abscess Seizure disorder Craniotomylneurosurgery CNS bleed due to cerebral AVM Migraines Bell's palsy
Rendu-Osler-WeberSyndrome
Percent (%)
Initial Presentation
Lifetime
5 4 3 4
3 1 1 1 1 0
1 (fatal)
5 1
8 1
7
7
3
CNS = central nervous system; AVM = arteriovenous malformation; PAVM = pulmonary arteriovenous CVA = cerebrovascular accident; malformation.
Results No Treatment Eight patients, seen between 1964 and 1978, had no treatment. Four of the 8 were first seen at a young age (range, 18 to 48 years) with minimal symptoms of mild dyspnea on exertion. Confirmatory studies (tomography or angiography) documented one or more PAVMs, and subsequently these patients were lost to follow-up. In another patient, a solitary PAVM was noted on a chest roentgenogram during admission for terminal cardiac failure at age 63 years. Three patients received no therapy for their PAVMs because of other medical conditions that were thought to contraindicate surgical resection of the PAVMs. Their case histories are summarized briefly and illustrate the major morbidity associated with the neurologic complications of untreated PAVMs. In 1964, a 48-year-old man with R-0-W syndrome had angiographic confirmation of four large bilateral PAVMs. Initially, no treatment was given. He was seen 9 years later with a left frontal brain abscess, which required craniotomy. He refused staged bilateral thoracotomies. Over the next 7 years, the patient was admitted three times with central nervous system complaints, including recurrent seizures and a major hemispheric stroke. PATIENT 1.
A 72-year-old woman with known R-0-W syndrome had angiographic documentation of a single PAVM and at least two cerebral arteriovenous malformations. She received no treatment because of advanced age and the presence of the cerebral lesions. She was admitted on multiple occasions for transient hemiparesis with aphasia and sustained a major stroke 10 years later.
PATIENT 2.
A 28-year-old woman without R-0-W syndrome was seen with a transient hemianopsia, right hemiparesis, and an abnormal chest roentgenogram. Pulmonary arteriogram revealed at least five basilar PAVMs bilaterally. No specific treatment was undertaken, and the symptoms spontaneously resolved. Nine years later, a PATIENT 3.
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Table 4. Surgical Management of Pulmonary Arteriovenous Malformations No. of PAVMs
Lobectomy
Multiple Segmentectomies
Segmentectomy
Subsegmental Excision
Solitary Multiple unilateral Multiple bilateral Total P A W S = pulmonary arteriovenous malformations.
second episode of transient hemiparesis occurred. The chest roentgenogram at that time was unchanged, and cerebral angiography showed no abnormality. No specific therapy was given. Twenty-two years later, she was seen with a left thalamic brain abscess. Stereotactic drainage of the brain abscess was performed, and the patient underwent a long and incomplete rehabilitation.
Surgical Resection Eight patients had primary surgical excision of their PAVMs, and a ninth patient underwent surgical excision after documented recurrence of a PAVM after balloon embolization therapy (Table 4). There was no postoperative morbidity or mortality. All patients have remained well without documented recurrence or growth of new PAVMs. Median follow-up is 12 years (range, 1 to 25 years). Three patients underwent segmentectomy for single unilateral PAVMs. Four patients underwent lobectomy: 2 for solitary PAVMs (both right middle lobe), 1for multiple PAVMs confined to the right lower lobe, and 1 for multiple large PAVMs in the right lower lobe, with multiple tiny PAVMs left elsewhere. All of these patients were relieved of their symptoms, and none had postoperative recurrence or enlargement of the PAVMs. There were no postoperative neurologic complications attributable to the PAVMs. One patient underwent staged bilateral thoracotomies for multiple bilateral lesions. The case history follows. A 17-year-old girl was seen with decreased exercise tolerance, fatigue, clubbing, and cyanosis of 4 years’ duration. She had a family history of hereditary hemorrhagic telangiectasia but had no cutaneous telangiectasias herself. A pulmonary angiogram showed PAVMs of the posterior segment of the right upper lobe, the medial basal segment of the right lower lobe, the anteromedial basal segment of the left lower lobe, and the lingula of the left upper lobe. She had a hematocrit of 0.48 and a calculated shunt fraction of 0.36. Pulmonary function studies were normal. Staged surgical procedures were planned because of her young age and the belief that the lesions were all amenable to surgical resection. At the first operation, she underwent posterior segmentectomy of the right upper lobe and medial basal segmentectomy of the right lower lobe. Arterial blood gas analysis was done before and after these resections (Table 5). The postoperative course was unremarkable. One year later PATIENT 4.
she underwent basal segmentectomy of the left lower lobe and multiple wedge resections of many smaller lesions on both the left upper and lower lobes. She had an uneventful recovery and has remained asymptomatic during 10 years of follow-up.
Balloon Occlusion of PAVMs Five patients underwent balloon occlusion of PAVMs. In 3 patients, multiple balloons were placed angiographically to occlude multiple PAVMs associated with R-0-W syndrome. One of them underwent multiple embolizations of numerous PAVMs with a total of six balloons; three of these balloons subsequently could not be found on follow-up chest roentgenograms. One patient had the largest of multiple PAVMs embolized with little improvement in pulmonary shunting. She ultimately died of hemorrhage from multiple cerebral arteriovenous malformations. The third patient had numerous PAVMs requiring multiple repeated balloon embolizations at another institution. He was admitted on two separate occasions to our institution with brain abscess and major stroke. Two patients, whose case histories follow, had a solitary PAVM occluded. One of them underwent surgical excision 5 years later and the other, repeat balloon embolization 4 years later after documented recanalization of the PAVM. PATIENT 5. A 35-year-old man without R-0-W syndrome was seen in 1981 with acute right hemiparesis and expressive aphasia. A carotid arteriogram documented an embolus to the middle cerebral artery. Chest roentgenography and pulmonary angiography demonstrated a solitary subpleural PAVM in the left lower lobe. The neurologic deficits resolved, and the patient chose to have balloon embolization rather than surgical excision. The large PAVM was occluded with a 2-mm Becton-Dickinson(Fair-
Table 5 . Results of Arterial Blood Gas Analysis in Patient 4 Oxygen Tension (mm Hg) Inspired Gas
Preop
RUL Segmentectomy
RLL Segmentectomy
Room air 100% oxygen
54 72
NA 104
176
NA = not available; lobe.
RLL = right lower lobe;
76 RUL
=
right upper
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PUSKAS ET AL PULMONARY ARTERIOVENOUS MALFORMATIONS
field, NJ)detachable balloon (inflated to 8 mm in diameter), and angiography confirmed occlusion of the PAVM. A chest roentgenogram 4 months later showed stable position of the balloon and involution of the PAVM. Results of a lung scan at that time were consistent with occlusion of the PAVM. The patient was asymptomatic for 5 years after this procedure. In 1986, the balloon was not visible on routine surveillance chest roentgenogram. Pulmonary angiography confirmed recurrence of the PAVM. The patient opted for surgical resection. Feeder vessels of the solitary large PAVM were isolated and doubly ligated before cautery excision of the subpleural lesion. The patient did well postoperatively without recurrence of the PAVM on chest roentgenography or any neurologic complications during 6 years of follow-up. In 1986, a 42-year-old woman without R-0-W syndrome complained of migraines and fatigue. Chest roentgenography and angiography demonstrated a large solitary PAVM in the right lower lobe. Two balloons were placed in two large feeder vessels, and angiography confirmed occlusion of the PAVM. Four years later, she complained of vague neurologic deficits associated with the migraines. No balloons were visible on chest roentgenograms, and angiography documented recanalization of the PAVM. She underwent sequential embolization of the PAVM with both a metal coil and a ;siliconeballoon and has been in stable condition during 2 years of followUP. PATIENT 6.
Comment Pulmonary arteriovenous malformations are an uncommon clinical problem. The classic triad of dyspnea on exertion, cyanosis, and clubbing should ,alert the physician to the possibility of a PAVM, but it was unequivocally present in only 2 (10%) of our patients. Other signs and symptoms were more frequently seen (see Table 1). Pulmonary arteriovenous malformations are iisually congenital; however, there are reports of acquired PAVMs after infection [3], metastatic carcinoma [6], or trauma [5]. Consistent with other reports [3, 7, 81, hereditary hemorrhagic telangiectasia (R-0-W syndrome) was diagnosed in 12 (57%)of our patients. All patients with this syndrome should be screened for PAVMs by contrast computed tomographic scan. Paradoxical emboli may cause major neurologic deficits [16, 181, and central nervous system complaints may be the first manifestation of PAVM [15]. Seven of our patients presented with major neurologic findings. Brain abscess is a devastating complication of PAVM and occurred in 3 of our patients. The high incidence of associated major neurologic complications mandates aggressive treatment of PAVM whenever feasible. The goals of therapy for PAVM are twofold: to reduce or eliminate the pulmonary shunt and to prevent the devastating neurologic consequences of paradoxical embolism. All patients who had surgical resection were relieved of dyspnea, and none experienced further neurologic complications.
Ann Thorac Surg 1993;5625M
There is an association between cerebral arteriovenous malformations and PAVMs, especially in patients with R-0-W syndrome [16]. Three of our patients had documented cerebral arteriovenous malformations. All patients with PAVMs should be screened for cerebral malformations by contrast computed tomography or magnetic resonance imaging. The chest roentgenogram often suggests the presence of a PAVM. If doubt exists about a mass on the chest roentgenogram, chest tomograms, computed tomograms, or pulmonary arteriograms will usually be diagnostic. Pulmonary arteriography should be done before surgical intervention to document the number and location of all lesions. Pulmonary arteriovenous malformations predominantly affect the lower lobes. In our series, more than 70% of all lesions were in the lower lobes and were equally distributed between the right and left lower lobes. These malformations are more often solitary than multiple [8]; 57% of our patients had a solitary PAVM. Bilateral lesions have been reported more commonly in patients with hereditary hemorrhagic telangiectasia (R-0-W syndrome) [5, 81. Of the 8 patients in our series with bilateral PAVMs, 6 had R-0-W syndrome. There has been some dispute about whether PAVMs enlarge with time [2, 41. One of 3 patients who had serial pulmonary arteriograms had documented enlargement of a PAVM. Although multiple residual tiny PAVMs may contribute to substantial pulmonary shunting after resection of dominant PAVMs, we have not documented growth of or embolic complications from these residual tiny lesions. We believe that if these lesions do enlarge over time [7], it is likely to be a very slow process. Careful surveillance of patients with such lesions is advised. Lung-conserving resection is optimal therapy for PAVMs. It guarantees successful elimination of the PAVM and has minimal morbidity and mortality. Segmentectomy or local excision is the procedure of choice whenever possible. Staged bilateral thoracotomies are a viable option in the otherwise healthy patient with bilateral disease [ l l ] . Therapeutic embolization of the pulmonary artery offers another treatment option. Metal coils were used initially [13], but detachable balloons, used alone or in combination with coils, have recently become more popular [8, 14, 191. Details of the technique are reported elsewhere [19]. Balloon embolization is a suitable alternative to surgical intervention in elderly patients, patients who are poor surgical risks, patients with multiple lesions in whom surgical excision would sacrifice excessive lung tissue, and patients who decline surgical intervention. Patients tolerate balloon embolization well, and complications are infrequently reported [8, 191. However, 1 of our patients sustained a pulmonary infarction and pleural effusion during staged placement of multiple balloons. This patient also had a transient episode of aphasia due to a thromboembolic event. The incidence of balloon migration at the time of angiographic placement is reported to be low [19, 201. Systemic embolization of balloons or thrombus during angiographic placement is a potentially
Ann Thorac Surg 1993;5625>8
catastrophic complication, as the balloon can embolize into any portion of the systemic circulation. Delayed deflation of balloons, as occurred in 3 of our patients (60% of those treated with balloon embolization), is also potentially dangerous. In 2 of these patients, angiography documented recanalization of solitary PAVMs 4 and 5 years after balloon occlusion. Reports of embolization therapy [19, 201 do not adequately document long-term follow-up with serial chest roentgenograms and oximetry to evaluate the incidence of delayed balloon deflation and recurrence of PAVMs. Simple ligation has been abandoned as a surgical procedure for PAVMs because of the difficulty of finding all feeder vessels and the high incidence of recanalization of PAVMs through tiny accessory vessels [7]. Also, balloon embolization simply occludes the afferent vessel or vessels to the PAVM and may be associated with a higher incidence of late recurrence than has been appreciated. Balloon embolization must be further evaluated by longterm follow-up and careful documentation of the risks of balloon migration, clot propagation, and recurrence of PAVMs.
References 1. Churton T. Multiple aneurysms of pulmonary artery. Br Med J 1897;1:1223. 2. Gomes MR, Bernatz PE, Dines DE. Pulmonary arteriovenous fistulas. Ann Thorac Surg 1969;7:582-3. 3. Mansour KA, Hatcher CR Jr, Logan WD Jr, Abbott OA. Pulmonary arteriovenous fistula. Am Surg 1971;37:203-8. 4. Dines DE, Arms RA, Bernatz PE, Gomes MR. Pulmonary arteriovenous fistulas. Mayo Clin Proc 1974;49:460-5. 5. Dines DE, Seward JB, Bernatz PE. Pulmonary arteriovenous fistulas. Mayo Clin Proc 1983;58:176-81. 6. Prager RL, Laws KH, Bender HW Jr. Arteriovenous fistula of the lung. Ann Thorac Surg 1983;36:231-9. 7. Bosher LH, Blake AD, Byrd BR. An analysis of the pathologic anatomy of pulmonary arteriovenous aneurysms with par-
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ticular reference to the applicability of local excision. Surgery 1959;45:91-104. 8. Burke CM, Safai C, Nelson DP, Raffin TA. Pulmonary arteriovenous malformations: a critical update. Am Rev Respir Dis 1986;134:334-9. 9. Hepburn J, Dauphinee JA. Successful removal of hemangioma of the lung followed by the disappearance of polycythemia. Am J Med Sci 1942;204:681-5. 10. Parker EF, Stallworth JM. Arteriovenous fistula of the lung treated by dissection and excision without pulmonary excision. Surgery 1952;32:31-8. 11. Brown SE, Wright PW, Renner JW, Riker JB. Staged bilateral thoracotomies for multiple pulmonary arteriovenous malformations complicating hereditary hemorrhagic telangiectasia. J Thorac Cardiovasc Surg 1982;83:285-9. 12. Porstmann W. Therapeutic embolization of arteriovenous pulmonary fistula by catheter technique. In: Kelop 0, ed. Current concepts in pediatric radiology. Berlin: Springer, 197723-31. 13. Taylor BG, Cockerill EM, Manfredi F, Klatte EC. Therapeutic embolization of the pulmonary artery in pulmonary arteriovenous fistula. Am J Med 1978;64:360-5. 14. Terry PB, Barth KH, Kaufman SL, White RI. Balloon embolization for treatment of pulmonary arteriovenous fistulas. N Engl J Med 1980;302:1189-90. 15. Momma F, Ohara S, Ohyama T, Mot0 A, Okada H, Harada H. Brain abscess associated with congenital pulmonary arteriovenous fistula. Surg Neurol 1990;34:439-41. 16. Roman G, Fisher M, Per1 DP, Poser CM. Neurological manifestations of hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease): report of 2 cases and review of the literature. Ann Neurol 1978;4:130-44. 17. Sluiter-Eringa H, Orie NGM, Sluiter HJ. Pulmonary arteriovenous fistula: diagnosis and prognosis in noncompliant patients. Am Rev Respir Dis 1969;100:177-84. 18. Press OW, Ramsey PG. Central nervous system infections associated with hereditary hemorrhagic telangiectasia. Am J Med 1984;7786-92. 19. White RI, Lynch-Nyhan A, Terry P, et al. Pulmonary arteriovenous malformations: techniques and long-term outcome of embolotherapy. Radiology 1988;169:663-9. 20. Hughes JMB, Allison DJ. Pulmonary arteriovenous malformations: the radiologist replaces the surgeon. Clin Radio1 1990;41:297-8.
DISCUSSION DR DENTON A. COOLEY (Houston, TX): Is anyone curious about where those balloons are now that were not identified? DR JOSEPH S. McLAUGHLIN (Baltimore, MD): I congratulate Dr Puskas, Dr Mathisen, and their associates on this excellent report and particularly Dr Puskas for his excellent presentation. This is not a large series; it is not even a particularly unique series; but it is a very important series because it revisits a subject that requires reevaluation. An isolated, small arteriovenous malformation with a single vessel leading to it is easily treated either by embolization of the vessel or by surgical resection of the lesion. Both techniques give very good results. This is not the case for large arteriovenous malformations with multiple arteries. On examination of a cut section, one can see the sinusoids, which allow embolization to occur from the systemic circulation through the sinusoids out to the systemic circulation. When this happens, all too often emboli reach the brain and
produce large areas of necrosis. These large arteriovenous malformations are not well treated by embolization. I have three questions for Dr Puskas and Dr Mathisen. First, they recommend the use of bilateral or staged bilateral thoracotomies to treat patients who have multiple fistulas bilaterally. I wonder if they have given any thought to the use of a sternotomy incision to attack both lungs at the same time. Second, they talked about complications of the procedure itself, which are mostly related to Rendu-Osler-Weber syndrome. What about the complications that occur from the operation per se in this kind of situation? Third, and this is really the crux of the matter, a man named White, who was previously in Baltimore and who, I believe, is now chief of radiology at Yale, has presented nearly 300 of these fistulas treated by embolization either with balloons or with metal coils. If memory serves me, he has had only two major complications in these patients. This is in marked contrast to the data presented. I would appreciate the authors’ comments on why
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PULMONARY ARTERIOVENOUS MALFORMATIONS
there is this marked discrepancy between what has occurred with Dr White’s series of embolizationand what has happened in their series.
DR PUSKAS: I thank the discussants for their remarks. In
response to Dr Cooley’s important question, we do not know where the balloon is in the 1 patient who underwent balloon therapy at our institution and subsequently had surgical intervention. The surgical specimen did not contain the balloon. There was no evidence that it had migrated to the central nervous system, and the patient had no particular symptoms that would lead us to know where the balloon had migrated. In response to Dr McLaughlin’sfirst question about the role of sternotomy in the management of bilateral pulmonary arteriovenous malformations, in the patient in whom we resected bilateral lesions, we chose bilateral staged thoracotomies because the lesions were typically posterior and in the lower lobes. This is, in fact, the most common location for these lesions, and it is the area of pulmonary parenchyma most awkward to resect through a sternotomy. However, for patients who have more anterior or superior lesions that could be easily resected through a stemotomy, we think a stemotomy would serve well. With respect to the surgical complications in our series, we operated on 9 patients and had no surgical complications after routine thoracotomies and parenchyma-conserving resections. In response to Dr McLaughlin’s remarks about Dr Robert
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White’s radiologic series from both Johns Hopkins and now Yale University Medical Center, Dr White published in 1988a series of 276 pulmonary arteriovenous malformations that were embolized in 76 patients. In his series, 90% of patients had RenduOsler-Weber syndrome, and he was dealing with multiple bilateral arteriovenous malformations in most of the patients. He had two early complications related to inadvertent migration of balloons during their angiographic placement. One of the balloons was located in the hepatic artery and one, in the hypogastric artery of those 2 patients. Ten percent of his patients had pleurisy and pleural effusions, and there was a major thrombophlebitis in 1 patient, which required long-term anticoagulation. Those were the complications related to the angiographic procedure itself. Only 16 of the 76 patients had repeat angiography. Those patients underwent repeat embolization of the very numerous pulmonary arteriovenous malformations. Dr White has very limited follow-up of those patients, as they are referred to him from all over the world. In conversations with me, he has said that less than 20% have accurate long-term follow-up in his data at Yale. Although he states that there have been no complications from migration of balloons, he does acknowledge that after balloon therapy several patients have had strokes or brain abscesses. None of the patients treated surgically in our smaller series sustained either a surgical or a postoperative neurologic complication.