Eur J Cardiothorac Surg 2000;18:535-539
© 2000 Elsevier Science NL
Surgical repair of the pulmonary trunk aneurysm
Kenji Kuwaki,
Kiyofumi Morishita,
Hiroki Sato,
Raimi Urita,
Tomio Abe
Departments of Thoracic and Cardiovascular Surgery, Sapporo Medical University School of Medicine, South 1, West 16, Chuo-ku, Sapporo, 060-0061, Japan
Received 19 May 2000;
received in revised form 2 August 2000;
accepted 5 September 2000.
Corresponding author. Tel.: +81-11-611-2111, ext. 3312; fax: +81-11-613-7318
 |
Abstract
|
|---|
Objective: Aneurysm formation of the pulmonary trunk is rare and there is controversy about optimal treatment for this disease. The aim of this article is to report four patients with pulmonary trunk aneurysm which were managed by surgical repair. Materials and methods: From 1986 to 1997, we performed surgical repair for pulmonary trunk aneurysm in four patients. There was one male and three female patients with a mean age of 63.3 years (range: 54–78 years). Concomitant diseases were cardiac valvular disease in four patients, thoracic aortic dissection in two, atherosclerotic abdominal aortic aneurysm in two, and coronary artery disease in one. All patients were in New York Heart Association functional class III preoperatively. Surgical procedures for the pulmonary trunk aneurysm included Dacron graft replacement in two patients and aneurysmorrhaphy in two. Associated procedures were cardiac valvular operation in three patients with four lesions and right ventricular outflow tract reconstruction (RVOTR) in one. Results: There were no operative mortalities and no late deaths with a mean follow-up period of 6.6 years (range: 2.4–10.0 years). One female patient developed recurrent pulmonary trunk aneurysm 9.5 years after aneurysmorrhaphy, and underwent a second operation where Dacron graft replacement of the aneurysm including pulmonary valve replacement was performed successfully. All patients are now leading normal lives. Conclusions: Surgical management should be considered for large aneurysm of the pulmonary trunk regardless of its etiology and underlying disease to prevent possible rupture with fatal result if the patient has an acceptably low operative risk.
Key Words: Pulmonary trunk aneurysm • Surgical repair • Graft replacement • Aneurysmorrhaphy
|
1. Introduction
|
|---|
Pulmonary trunk aneurysm is a rare lesion. Previous reports demonstrated several associated diseases such as structural cardiac abnormalities, structural vascular abnormalities, pulmonary hypertension, and infection [1–11], but idiopathic pulmonary trunk aneurysm without any associated disease has also been reported [12,13]. There is no definitive therapeutic approach for this lesion because of the paucity of information about its natural history and the long-term outcome following medical or surgical intervention.
We describe here four cases of pulmonary trunk aneurysm which were treated surgically to prevent future fatal complication of rupture.
|
2. Materials and methods
|
|---|
Between April 1986 and December 1997, we performed surgical management for pulmonary trunk aneurysm in four patients containing of one male and three females. The mean age at operation was 63.3 years (range 54–78 years). All patients had concomitant cardiac valvular disease including pulmonary valve lesion in three patients, mitral valve lesion in one, and aortic valve lesion in one. (Table 1). Two patients had both thoracic aortic dissection and atherosclerotic abdominal aortic aneurysm (Table 1). No patient had congenital heart disease with intracardiac shunt, or past or present history of infection such as tuberculosis, syphilis, bacteria, or fungus. Preoperative computed tomography of the chest revealed the aneurysm of from 6.0–7.3 cm in maximum diameter (mean±SD: 6.7±0.7 cm) (Table 1). Preoperative hemodynamic data are shown in Table 1.
All operations were performed through a median sternotomy with the use of cardiopulmonary bypass with moderate systemic hypothemia (28–30°C). The aneurysm of pulmonary trunk was repaired with Dacron graft replacement in two patients and aneurysmorrhaphy in two. One of the two patients with a graft replacement had straight graft replacement with a 30 mm Dacron prosthesis following resection of the pulmonary trunk aneurysm. Another patient had a Y-shaped graft replacement using 24 and 22 mm Dacron prostheses. Aneurysmorrhaphy was performed by excision of a large portion of the anterior aneurysmal wall of the pulmonary trunk followed by approximation of the two free edges of the arterial wall with continuous monofilament suture in two patients. All patients underwent concomitant cardiac procedure including pulmonary valve commissurotomy in two patients, re-open mitral commissurotomy, right ventricular outflow tract reconstruction (RVOTR) with patch, and aortic valve replacement each in one patient (Table 2).
|
3. Results
|
|---|
All patients survived the operation and their postoperative courses were uneventful. Follow-up was completed in all patients, and the mean follow-up period was 6.6 years (range: 2.4–10.0 years). There were no late deaths. One female patient developed recurrent pulmonary trunk aneurysm with pulmonary valve regurgitation 9.5 years after the initial aneurysmorrhaphy and RVOTR (patient 1), and was in New York Heart Association (NYHA) class III (Fig. 1) . The maximum diameter of the recurrent aneurysm was 11.0 cm by computed tomography. She has improved much since the second cardiac surgery where graft replacement of the recurrent pulmonary artery aneurysm and pulmonary valve replacement were performed. Thus, all patients were found to be in NYHA class I at present. Regarding the concomitant aortic disease including the two cases of aortic dissection and two at aortic aneurysm (AAA), all lesions were well controlled by medical treatment except in one case of AAA which was managed by surgical graft replacement 2 months after repair of the pulmonary trunk aneurysm (patient 3).
View larger version (109K):
[in this window]
[in a new window]
|
Fig. 1. Computed tomographic scan shows a recurrent pulmonary trunk aneurysm 9.5 years after aneurysmorrhaphy (patient 1).
|
|
Histologic examination of the resected pulmonary arterial specimen was available in three patients, and revealed mucoid degeneration of media and fragmentation of elastic fiber in two patients, and no abnormality in one.
|
4. Discussion
|
|---|
Aneurysm of the pulmonary trunk is very rare, and both the pathogenesis and natural history of this disease are poorly understood. Previous literatures have demonstrated several underlying diseases which were considered as possible risk factors for development of pulmonary trunk aneurysm: cardiac valvular disease [2–8], congenital heart disease with intracardiac shunting [8–10], vascular abnormalities [14,15,17,18], and pulmonary hypertension [7,9,10,16]. Major concomitant diseases in this study were aortic vascular abnormalities and pulmonary valve stenosis, which were observed in two and three out of our four patients, respectively, (Table 1).
Structural vascular abnormality due to vasculitis or connective tissue disorder should be discussed as a possible mechanism of pulmonary trunk aneurysm, especially in cases such as our patients 3 and 4 (Fig. 2)
who were both complicated with thoracic aortic dissection and abdominal aortic aneurysm. Hartley et al. [17], reported a similar case in which pulmonary and systemic arterial aneurysm in conjunction with aortic dissection occurred in the same patient, and on the basis of the patient's clinic and histological findings concluded that these multiple aneurysms resulted from unclassified arteritis. Dennison et al. [14], also demonstrated a case of simultaneous aortic and pulmonary aneurysm due to giant cell arteritis. In our patients, however, arteritis is unlikely to have been the cause of the pulmonary trunk aneurysms because the histologic study of the resected specimens of the pulmonary trunk artery and abdominal aorta revealed no finding of inflammation to suggest arteritis. The representative disease of connective tissue disorder that affects the large vessels is Marfan's syndrome. Although aortic aneurysm including aortic dissection is the main problem in Marfan's syndrome, dissecting pulmonary artery aneurysms were previously reported [18]. Two of our four patients had concomitant aortic dissection, but they had no family history or skeletal evidence of Marfan's syndrome. In addition, there was no macroscopic or microscopic evidence of pulmonary trunk aneurysm with dissection. Therefore, the association of an inheritable disorder of connective tissue with the occurrence of pulmonary trunk aneurysms in our cases is obscure.
View larger version (132K):
[in this window]
[in a new window]
|
Fig. 2. Preoperative digital subtraction angiogram (patient 4) shows a huge aneurysm of the pulmonary trunk.
|
|
Previous authors have also documented pulmonary artery aneurysm associated with pulmonary valve stenosis, and the pressure gradient over the pulmonary valve varied from 10 to 110 mmHg [2,4,5,13]. The pressure gradient in our case patients 3 and 4 were 35 and 39 mmHg, respectively, (Table 1). Therefore, the occurrence of pulmonary trunk aneurysm could have taken place without any relationship to the severity of pulmonary valve stenosis. Progression from poststenotic dilatation of pulmonic valve stenosis to pulmonary trunk aneurysm in the structural weakness of the pulmonary arterial wall, whether the histologic study of the aneurysmal wall revealed it to be abnormal or not, might be a possible explanation.
The histologic findings of aneurysmal wall in the previous study were fragmentation or decrease of elastic fiber in media [2,5,7,8,10,11,16], medial degeneration [9,15], increase of collagen fiber [7,8,10,11], and decrease of smooth muscle cell [2,8,10,11]. However, some authors have reported normal histology of the aneurysmal wall [4,16]. Some of these histologic findings were consistent with those of our cases which showed mucoid degeneration of media in two patients, fragmentation of elastic fiber in two, and no abnormal findings in one.
Management of pulmonary trunk aneurysm is a major concern, and there are no clear guidelines regarding surgical indication for its treatment. Some authors have recommended conservative treatment if there is no left-to-right intracardiac shunt or significant pulmonary hypertension, because previously such patients had a relatively benign prognosis with an uncomplicated course after between 1 and 7 years follow-up [6,12,13]. However, progressive enlargement of the pulmonary trunk aneurysm in the absence of intracardiac shunt and pulmonary hypertension during 4 years follow-up has been demonstrated [11]. Although rupture of pulmonary aneurysm has rarely been reported, one would suspect that, because the pulmonary aneurysm itself would always be asymptomatic, some patients with unrecognized pulmonary aneurysm may have suffered sudden death by aneurysm rupture. Therefore, in our opinion, if the patient has an acceptably low operative risk, surgical repair should be recommended for pulmonary trunk aneurysm regardless of its etiology or the underlying disease in order to prevent the possible fatal complication of rupture.
Several surgical techniques have been employed to repair pulmonary trunk aneurysm: aneurysmorrhaphy [5,8,9,10,15], Dacron graft replacement [7], pulmonary allograft replacement [4], and replacement by combined use of a stentless bioprosthesis and Dacron prosthesis [3]. Aneurysmorrhaphy is a relatively simple procedure and can be performed quickly, but it poses the adverse possibility of recurrent dilatation due to the continued presence of the aneurysmal wall, especially in cases of associated pulmonary hypertension or structural cardiac lesion. In fact, we experienced late progressive re-dilatation of the pulmonary trunk aneurysm 9.5 years after aneurysmorrhaphy in a 54-year-old female (Fig. 1), which was successfully treated by re-operation including Dacron graft replacement. Thus, at present, graft replacement after resection of the aneurysm is our surgical procedure of first choice for pulmonary trunk aneurysm whenever feasible.
|
References
|
|---|
- Bartter T., Irwin R., Nash G. Aneurysm of the pulmonary arteries–review. Chest 1988;94:1065-1075.[Free Full Text]
- Candales A.L., Kleiger R.E., Gomez J.A., Kouchoukos N.T., Botney M.D. Pulmonary artery aneurysm: review and case report. Clin Cardiol 1995;18:738-740.[Medline]
- Roth M., Reuthebuch O.T., Klövekorn W.P., Bauer E.P. Repair of an aneurysm of the pulmonary trunk in a 65-year-old patient. Ann Thorac Surg 1999;67:244-246.[Abstract/Free Full Text]
- Casselman F., Deferm H., Peeters P., Vanermen H. Aneurysm of the left pulmonary artery: surgical allograft repair. Ann Thorac Surg 1995;60:1423-1425.[Abstract/Free Full Text]
- Chen Y.F., Chiu C.C., Lee C.S. Giant aneurysm of main pulmonary artery. Ann Thorac Surg 1996;62:272-274.[Abstract/Free Full Text]
- Tami L.F., McElderry M.W. Pulmonary artery aneurysm due to severe congenital pulmonic stenosis. Case report and literature review. Angiology 1994;45:383-390.
- Williams T.E., Jr, Craenen J., Hosier D.M., Sirak H.D. Pulmonary artery aneurysm. Successful excision and replacement of the main pulmonary artery. J Thorac Cardiovasc Surg 1971;62:63-67.[Medline]
- Jaffin B.W., Gundel W.D., Capeless M.A., Castanede A.R., Rabinovitch M., Wackers F.J. Aneurysm of the pulmonary artery as a cause of severe chest pain. Arch Int Med 1983;143:1484-1485.
- Caralps J.M., Bonnin J.O., Oter R., Aris A. True aneurysm of the main pulmonary artery: surgical correction. Ann Thorac Surg 1978;25:561-563.[Abstract]
- Garcia-Rinaldi R., Howell J.F. Aneurysm of the main pulmonary artery: long-term survival after aneurysmorrhaphy and closure of a ventricular septal defect. Ann Thorac Surg 1976;21:180-183.[Abstract]
- Shimokawa S., Komokata T., Moriyama Y., Taira A. Aneurysm of pulmonary trunk (to the editor). Ann Thorac Surg 1997;64:586-587.[Free Full Text]
- Casselman F., Meyns B., Herygers P., Verougstraete L., Elst F.V., Daenen W. Pulmonary artery aneurysm: is surgery always indicated?. Acta Cardiol 1997;52:431-436.[Medline]
- Fang C.C., Tsai C.C. Idiopathic pulmonary artery aneurysm. J Formos Med Assoc 1996;95:873-876.[Medline]
- Dennison A.R., Watkins R.M., Gunning A.J. Simultaneous aortic and pulmonary artery aneurysms due to giant cell arteritis. Thorax 1985;40:156-157.[Free Full Text]
- Finch E.L., Mitchell S., Guthaner D.F., Fowles R.F., Miller D.C. Pulmonary artery surgical aneurysmorrhaphy: where do we go from here?. Am Heart J 1983;106:614-618.[Medline]
- Barbour D.J., Roberts W.C. Aneurysm of the pulmonary trunk unassociated with intracardiac or great vessel left-to-right shunting. Am J Cardiol 1987;59:192-194.[Medline]
- Hartley J.P.R., Dinnen J.S., Seaton A. Pulmonary and systemic aneurysms in a case of widespread arteritis. Thorax 1978;33:493-499.[Abstract/Free Full Text]
- Headley R.N., Carpentier H.M., Sawyer C.G. Unusual features of Marfan's syndrome including two postmortem studies. Am J Cardiol 1963;11:259-266.[Medline]
Top
Abstract
1. Introduction
