Asian Cardiovasc Thorac Ann 2004;12:360-362
© 2004 Asia Publishing EXchange Ltd
Ruptured Right Aortic Arch Aneurysm
Worawong Slisatkorn, MD,
Pansak Laksanabunsong, MD,
Punnarerk Thongcharoen, MD
Division of Cardiovascular Thoracic Surgery, Department of Surgery, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
For reprint information contact: Worawong Slisatkorn, MD Tel: 662 419 7998 Fax: 662 412 9160 Email: siwsl{at}mahidol.ac.th Division of Cardiovascular Thoracic Surgery, Department of Surgery, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
 |
ABSTRACT
|
|---|
A case of a ruptured right aortic arch aneurysm in a 74-year-old woman presenting with shock is reported. The diagnostic and operative findings are presented. We discuss the surgical approach and review the literature.
|
INTRODUCTION
|
|---|
A right aortic arch is an uncommon anomalous variation. An aneurysm of the right aortic arch is extremely rare. We report a patient presenting with a ruptured right aortic arch aneurysm with a retroesophageal aortic segment and comment on the technique used during the operation.
A 74-year-old woman with a history of right femoral deep vein thrombosis 5 years previously, and partially recovered from left ischemic "stroke" 5 months ago, presented with acute chest pain and shock. In the emergency room, her blood pressure could not be measured. She was very pale. After resuscitation with a liter of crystalloid fluid, her blood pressure rose to 80/50 mm Hg.
Physical examination revealed the patient had full consciousness, decreased breath sounds on the right side of the chest, normal heart sounds and motor power grade IV/VI in the left upper limb and grade II/VI in the left lower limb. The peripheral pulses were equal in all extremities. Blood tests showed hematocrit of 23%, blood urea nitrogen 33 mg·dL–1, and creatinine 2.6 mg·dL–1. Chest X-Ray revealed haziness of the right hemithorax. Computed tomographic (CT) scan of the chest showed an aortic arch aneurysm, 8 x 7 cm in diameter with a small aneurysm 2.9 x 3.5 cm in diameter at the distal aortic arch, and a massive right pleural effusion (Figures 1A & 1B
). The ECG showed Q wave in lead III. The patient was diagnosed as having a ruptured aortic arch aneurysm and was prepared for emergency surgery.
View larger version (137K):
[in this window]
[in a new window]
|
Figure 1. A CT scan of the chest demonstrates a large right aortic arch aneurysm (A) with a small distal arch aneurysm (B) and right pleural effusion.
|
|
A median sternotomy incision was performed. Cardiopulmonary bypass was commenced with right femoral artery and left femoral vein cannulation as the right femoral vein was thrombosed. After the chest was opened, a liter of blood was removed from a right hemithorax; the superior vena cava (SVC) and inferior vena cava were transatrially cannulated for additional drainage. The patient was cooled down to below 20°C. Circulatory arrest with retrograde cerebral perfusion via a SVC cannula was performed, and the central venous pressure was kept below 25 mm Hg. We found a right aortic arch aneurysm, which was ruptured at the posterior wall. A distal anastomosis to the descending aorta was performed at the hilar level using a trans-left pleural cavity approach with a 34 mm vascular graft. The three orifices of the head and neck vessels were identified and thought to be the left innominate artery, right common carotid artery, and right subclavian artery, respectively.
The orifice of the right subclavian artery was sacrificed to facilitate improved exposure for the anastomosis. The other two vessels were implanted into the vascular graft. The proximal part of the graft was clamped, the circulation was re-started, and the patient was re-warmed. Circulatory arrest time was 66 minutes. The proximal anastomosis was performed at the ascending aorta (Figure 2). During re-warming, there was massive bleeding in the operative field; the left radial arterial line pressure was 15 mm Hg. The anastomoses looked secure but the bleeding could not be controlled. Finally, we lost the patient in the operating room.
View larger version (35K):
[in this window]
[in a new window]
|
Figure 2. Operative finding and surgical technique. Asc. aorta = ascending aorta; Desc. aorta = descending aorta; LCCA = left common carotid artery; LSA = left subclavian artery; RCCA = right common carotid artery; RSA = right subclavian artery.
|
|
We extended the original incision to the left anteriorly and found the left subclavian artery, which came from the fourth branch of the aortic arch, and passed behind the trachea and esophagus. We failed to recognize that the left subclavian artery had caused the profuse bleeding and, hence, the reason for the low blood pressure detected in the left radial arterial line.
|
DISCUSSION
|
|---|
A right aortic arch is defined as an aortic arch that crosses over the right main bronchus.1 It is an uncommon anomaly, with an estimated prevalence of between 0.1% and 0.14%.2 Knight and Edwards analyzed 78 pathological specimens with a right aortic arch.3 In 4 cases, the right aortic arch was part of a double aortic arch. In 74 cases, the right aortic arch was the only arch and could be subdivided into two groups:
- A right aortic arch with a retroesophageal aortic segment (4%).
- A right aortic arch without a retroesophageal aortic segment (96%). This group can be further subdivided into those with:
- (2.1) mirror image branching (84.5%);
- (2.2) an aberrant left subclavian artery (14.1%);
- (2.3) isolation of the left subclavian artery (1.4%).
This patient belongs to group 1. In the literature, there are five reported cases of a right-sided aortic arch aneurysm, and the surgical approach and operative techniques used are summarized in Table 1.
In this case, however, the large aneurysm was on the right side, whereas the small aneurysm and the descending aorta were on the left side. In our opinion, a clamshell incision would have given the best exposure, which would have facilitated a one-stage procedure. Arterial pressure monitoring is also important, as it gives an indication as to whether both subclavian arteries are reimplanted.
In conclusion, a right aortic arch aneurysm is a rare variation, and the surgeon who deals with this condition needs to be aware of the associated anomalies in planning surgery.
|
REFERENCES
|
|---|
- Becker AE, Anderson RH. Malformation of the aortic arch. Pathology of congenital heart disease. London: Butterworths, 1986:321–38.
- Scandalakis JE, Gray SW, Symbas P. The thoracic and abdominal aorta. In: Scandalakis JE, Gray SW, editors. Embryology for surgeons. 2nd ed. Maryland: Lippincott, Williams & Wilkins, 1994:976–1030.
- Knight L, Edwards JE. Right aortic arch: types and associated cardiac anomalies. Circulation
1974;50:1047–51.[Abstract/Free Full Text]
- Tominaga R, Nishida T, Morita S, Masuda M, Yasui H. Atherosclerotic aneurysm in circumflex retroesophageal right aortic arch. Ann Thorac Surg
2001;71:2030–2.[Abstract/Free Full Text]
- Yasuda T, Yamamoto S, Ishida Y. Double aneurysms of arch and descending aorta associated with right aortic arch. Ann Thorac Surg
2000;70:1405–7.[Abstract/Free Full Text]
- Wakiyama H, Okada M, Yamashita C, Nakagiri K, Yoshimura N, Yoshida M, et al. Successful surgical treatment of an Edward type IIIB right aortic arch aneurysm: report of a case. Surg Today
1998;28:1098–101.[Medline]
- Imagawa H, Kadoba K, Taniguchi K, Sawa Y, Takahashi T, Fukushima N, et al. Saccular aneurysm in the right-sided aortic arch: a successfully corrected case. J Vasc Surg
1997;25:941–4.[Medline]
- Kameyama T, Okabayashi H, Shimada I, Ohno N, Noguchi N, Nishina T, et al. A case report of tracheal stenosis due to aortic arch aneurysm of retroesophageal right aortic arch associated with so called vascular ring-facial syndrome. Kyobu Geka
1995;48:945–7.[Medline]
TOP
ABSTRACT
INTRODUCTION
