Interact CardioVasc Thorac Surg 2009;8:431-434. doi:10.1510/icvts.2008.197491
© 2009 European Association of Cardio-Thoracic Surgery
Institutional report - Aortic and aneurysmal |
Early postoperative aortic rupture following surgery for acute type A aortic dissection
Naoyuki Kimuraa,*,
Masashi Tanakaa,
Koji Kawahitob,
Atsushi Yamaguchia,
Takashi Inoa and
Hideo Adachia
a Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, 1-847 Amanumacho, Omiya, Saitama 330-0834, Japan
b Department of Cardiac Surgery, Kashiwa Hospital, Jikei University School of Medicine, Kashiwa, Japan
Received 26 October 2008;
received in revised form 9 January 2009;
accepted 12 January 2009
*Corresponding author. Tel.: +81-48-647-2111; fax: +81-48-648-5188.
E-mail address: kimura-n{at}omiya.jichi.ac.jp (N. Kimura).
 |
Abstract
|
|---|
We report our experience with patients who died of early aortic rupture following surgical treatment for acute type A aortic dissection in a consecutive series of 324 patients who underwent surgery for this condition between 1991 and 2007. In-hospital mortality rate was 9.9% (32/324), and seven patients (two men, mean age, 67 years) died of postoperative aortic rupture. Rupture sites were the proximal aorta in two and distal aorta in five patients. Surgical procedures included ascending aorta replacement in six and ascending aorta plus aortic arch replacement in one. The common characteristics of the two patients with proximal aortic rupture were preoperative aortic insufficiency, intraoperative bleeding from the proximal stump, and high blood pressure before the rupture. In contrast, the distal aortic ruptures occurred in patients with uncomplicated postoperative courses, with three distal aortic ruptures occurring on the inpatient ward. The only common characteristic of the distal aortic ruptures was residual patent false lumen (80%, 4/5 patients), the other patient had a large pre-existing aneurysm in the descending thoracic aorta. Careful postoperative management, including strict blood pressure control, is especially important in patients with residual patent false lumen following surgery for acute type A aortic dissection.
Key Words: Acute type A aortic dissection; Aortic rupture; Patent false lumen
|
1. Introduction
|
|---|
Acute type A aortic dissection (AAAD) remains a serious cardiovascular disease associated with high in-hospital mortality [1]. Previous studies have reported common causes of in-hospital mortality following surgery for AAAD to include cardiac failure, multiorgan failure, neurological deficit, and aortic rupture [2–5]. However, few studies have focused on early postoperative aortic rupture following surgery for AAAD. We describe herein our experience with patients who died of this fatal complication after successful initial surgery for AAAD.
|
2. Materials and methods
|
|---|
Between January 1991 and October 2007, 324 consecutive patients (171 men, 153 women, mean age, 63.2± 12.0 years) with AAAD underwent surgery at our hospital. Aortic dissection was diagnosed on the basis of enhanced computed tomography (CT) or echocardiography findings. Clinical background and preoperative characteristics of the 324 patients are shown in Table 1.
View this table:
[in this window]
[in a new window]
|
Table 1 Clinical background and preoperative characteristics of all patients undergoing surgery for acute type A aortic dissection
|
|
Emergent surgery was performed in all patients within 14 days of acute onset of symptoms, with 91.0% (295/324) of these surgeries being performed within 48 h of onset. Although surgical techniques have evolved somewhat over the time course of this series, the basic principals involved replacement of the ascending aorta and resection of the primary entry site by open distal anastomosis during a period of deep hypothermic circulatory arrest. From 1991 to 1996, ringed intraluminal graft insertion was performed in 16 patients. Once cardiopulmonary bypass was established, systemic cooling was started. The aorta was clamped after onset of ventricular fibrillation. During cooling period, the proximal stump was trimmed, and two Teflon felt strips (DuPont, Parkersburg, WV) were placed inside and outside of the aorta for reinforcement. The native aortic valve was preserved whenever feasible. The main technical features of valve re-suspension included complete transection of the proximal aorta at the level of the sinotubular junction, obliteration of the proximal false lumen with the two Teflon felt strips, and re-suspension of the aortic valve commissures with circumferential suture reconstruction of the aorta. The aortic arch was then explored under circulatory arrest at a rectal temperature of 20 °C. The extent of graft interposition was determined by operative findings. If the entry site was located in the ascending aorta, ascending aorta replacement (including hemiarch replacement) was performed by the open aorta technique. If the entry site was present in or extended into the aortic arch, partial or total arch replacement was performed with a selective cerebral perfusion technique. When the entry site could not be identified or was identified in the descending thoracic aorta by transesophageal echocardiography, we simply replaced the ascending aorta. The distal stump was trimmed, and two Teflon felt strips were placed in the same fashion to the proximal stump. The placement technique always included the interposition of woven collagen-impregnated or albumin-sealed grafts with Teflon felt reinforcement of the aortic stumps. Gelatin-resorcin-formalin (GRF) adhesive was not used. Aortic root replacement with composite prosthesis and reimplantation of the coronary arteries by the modified Bentall technique was performed in patients with conspicuous dilatation of the aortic root. Operative characteristics of all patients are shown in Table 2.
In-hospital mortality was 9.9% (32/324). Five patients (1.5%) died in the operating room, and 27 (8.4%) died in the intensive care unit (ICU) or on the inpatient ward. The leading cause of death was cardiac failure (n=13), followed by postoperative aortic rupture (n=7), multiorgan failure (n=4), brain damage (n=3), bleeding (n=3), and visceral ischemia (n=2).
We studied the clinical charts of the seven patients (2 men, 5 women, mean age, 67.0±12.5 years, range 42–76 years) who died of early postoperative aortic rupture. Aortic rupture was diagnosed by autopsy in two, or by clinical course with postmortem X-ray or echocardiographic examination in five patients. Our study followed the guidelines of the Ethical Review Board of Jichi Medical University.
|
3. Results
|
|---|
The site of rupture included the proximal aorta in two and the distal aorta in five patients. The average interval between surgery and rupture was 7.9±3.4 days (range, 4–13 days). Operative procedures included ascending aorta replacement (plus CABG) in six patients and ascending aorta plus aortic arch replacement in one patient.
The perioperative characteristics of the two patients who died of proximal aortic rupture are shown in Table 3. These proximal aortic ruptures occurred in the ICU within seven days of surgery. Although the preoperative aortic root diameters of 45 mm and 43 mm in these two patients did not indicate obvious dilation, both patients presented with moderate or severe aortic valve insufficiency. The common intraoperative findings were a fragile aortic root and bleeding from the proximal stump. The postoperative course was complicated in both patients. Patient 1 was a 75-year-old woman who required prolonged mechanical ventilation due to impairment of oxygenation. She was tracheally extubated on postoperative day (POD) 6, but her blood pressure rose to 200/110 mmHg within 1 h of extubation. Aortic rupture subsequently occurred, and she suddenly collapsed and died. Autopsy revealed the rupture site to be 1 cm proximal of the proximal stump. Patient 2 was a 42-year-old man who also required prolonged mechanical ventilation due to a preoperative neurological complication. On POD 4, his blood pressure temporally rose to 180/82 mmHg and he subsequently collapsed and died. Postmortem echocardiography revealed massive pericardial effusion, which suggested that proximal aortic rupture had occurred due to inadequate blood pressure control. No autopsy was performed.
View this table:
[in this window]
[in a new window]
|
Table 3 Profiles of patients with early proximal aortic rupture following surgery for acute type A aortic dissection
|
|
The perioperative characteristics of the patients who died of distal aortic rupture are presented in Table 4. The average interval from surgery to rupture was 9.0±3.4 days (range, 5–13 days). Ruptures occurred in the ICU in two patients, and on the inpatient ward in three patients. The mean preoperative diameter of the aortic arch was 44±4.9 mm (range, 39–54 mm), and that of the descending thoracic aorta was 43±18 mm (range, 32–75 mm). The initial surgery included ascending aorta replacement (plus CABG) in four and ascending aorta plus aortic arch replacement with the elephant trunk technique in one patient. Entry resection was achieved in three patients. Bleeding from the distal stump was found in two of the five patients. The residual false lumen was patent in four of the five patients (Fig. 1). The only patient with a thrombosed false lumen was patient 4, who had a large concomitant aortic aneurysm in the descending thoracic aorta. The postoperative courses of the five patients were uncomplicated, and systolic blood pressure was controlled between 120–150 mmHg with antihypertensive drugs.
View this table:
[in this window]
[in a new window]
|
Table 4 Profiles of patients with early distal aortic rupture following surgery for acute type A aortic dissection
|
|
View larger version (100K):
[in this window]
[in a new window]
|
Fig. 1. Representative images of patent false lumen. Postoperative computed tomography scan of patient 3 performed on POD 3 shows the residual patent false lumen in the distal aorta following ascending aorta and aortic arch replacement. The distal aorta ruptured on POD 5. (a) Transverse section at the level of the distal stump (arrow: site of distal stump). (b) Sagittal section.
|
|
|
4. Discussion
|
|---|
With advances in surgical techniques and perioperative care, clinical outcomes of patients with AAAD have recently improved. Several groups have reported excellent short-term outcomes, with in-hospital mortality ranging from 6% to 13% [5–7]. The 9.9% (32/324) in-hospital mortality rate in our patients appears to be acceptable, however, we must recognize this complication has to be considered a technical or strategical failure of the surgical technique.
Postoperative proximal aortic redissection has recently been reported to occur at the site of GRF glue application [8, 9]. However, we did not use any GRF adhesive glue. Preoperative moderate to severe aortic valve insufficiency and bleeding from the proximal stump were the common characteristics of the two patients who died of proximal aortic rupture. Aortic valve insufficiency accompanied by AAAD is mainly due to dilation of the annulus with dislocation and loss of commissural support of the leaflets. Therefore, preoperative moderate to severe aortic valve insufficiency may indicate that the aortic root is extensively involved by the dissection process. In such cases, the diseased aortic root tends to be fragile, and we sometimes encounter refractory bleeding from the proximal stump. We consider that complete excision of dissected aortic wall during surgery might have prevented the proximal ruptures in those patients. Another common characteristic of the proximal ruptures was extremely high blood pressure before rupture. Even after obtaining successful intraoperative hemostasis, high blood pressure in the early postoperative period may increase the pressure on the proximal stump and induce proximal rupture. Careful postoperative management may reduce the risk of proximal aortic rupture.
Optimal surgical technique for proximal repair remains controversial [5, 10, 11]. In the present study, 89% of the 324 patients were treated with the aortic valve re-suspension technique, and the incidence of early proximal rupture was low (0.7%, 2/288 patients). Regarding indication for composite aortic root replacement, we think that, with the exception of patients with Marfan's syndrome or annuloaortic ectasia, most patients with AAAD complicated by aortic valve insufficiency can be successfully treated with commissural re-suspension and supracoronary aortic grafting, as similarly reported by Lai et al. [11]. However, composite aortic root replacement can increasingly safely be used for emergent surgery for AAAD [5]. If operative findings show aortic root is extensively involved by the dissection process, composite aortic root replacement may be a useful treatment option even in patients who do not present annuloaortic ectasia.
The distal aortic ruptures occurred in patients with uncomplicated postoperative courses. One common characteristic of the distal aortic ruptures was the occurrence of residual patent false lumen in 80% of the patients. Our previous study demonstrated that the incidence of residual patent false lumen in hospital survivors following surgery for type I or III b retrograde AAAD was 64% (124/193) [12]. Although we did not perform statistical analysis, the incidence of residual patent false lumen in patients who died of early distal aortic rupture was higher than that of hospital survivors. Careful postoperative management, including strict blood pressure control, is especially important in patients with residual patent false lumen. Patent false lumen has been reported to be a risk factor for late enlargement of the dissecting aorta or late distal reoperation [5, 13]. Some groups have advocated that extended aortic arch replacement at initial surgery, irrespective of the entry site location, may reduce the incidence of postoperative residual patent false lumen [7, 14]. In the present study, 4 of the 5 patients with distal aortic rupture underwent ascending aorta replacement only. Extended aortic arch replacement might have prevented the distal aortic ruptures. Although the extent of aortic replacement has also been reported to be a significant risk factor for hospital mortality [2, 4], excellent surgical outcomes of this approach have been reported [7, 14]. We think that extended aortic arch replacement would be a preferred treatment option in stable young patients who show enlargement of the distal aorta. Furthermore, a favorable result of extended aortic arch replacement with open stent-graft replacement for AAAD was recently reported [15]. Hybrid treatment may be another effective approach for prevention of distal aortic rupture.
In the present study, distal aortic rupture occurred in three patients with a preoperative aortic arch or descending thoracic aorta diameter >45 mm. Although an enlarged dissecting aorta is not uncommon in patients with AAAD, concomitant pre-existing thoracic or abdominal aortic aneurysm in our patients with AAAD was relatively rare; only four thoracic aortic aneurysms (maximum diameter >60 mm) and seven abdominal aortic aneurysms (maximum diameter >50 mm) were seen at the time of diagnosis of AAAD (Table 1). For those patients, we performed staged surgery for pre-existing aortic aneurysm within six months after the initial surgery for AAAD; however, one patient (patient 4) died of distal aortic rupture on POD 10. Therefore, concomitant aortic aneurysm may be another important risk factor for early distal aortic rupture. Immediate treatment for this pathology can avoid aortic rupture, and preceding endoluminal stent-graft placement can be a useful treatment option in such a patient.
|
5. Conclusions
|
|---|
Of the consecutive 324 patients who underwent surgery for AAAD, seven patients (2.1%) died in hospital postoperatively due to early postoperative aortic rupture. The site of rupture included the proximal aortic in two and the distal aortic in five patients. High blood pressure appeared to be associated with these proximal ruptures in the early postoperative period. However, distal aortic rupture was unpredictable and occurred in patients with uncomplicated postoperative courses. Careful postoperative management, including strict blood pressure control, is especially important in patients with residual patent false lumen in the distal aorta.
|
References
|
|---|
- Trimarchi S, Nienaber CA, Rampoldi V, Myrmel T, Suzuki T, Mehta RH, Bossone E, Cooper JV, Smith DE, Menicanti L, Frigiola A, Oh JK, Deeb MG, Isselbacher EM, Eagle KA, International registry of acute aortic dissection investigators. Contemporary results of surgery in acute type A aortic dissection: the international registry of acute aortic dissection experience. J Thorac Cardiovasc Surg 2005;129:112–122.[Abstract/Free Full Text]
- Crawford ES, Kirklin JW, Naftel DC, Svensson LG, Coselli JS, Safi HJ. Surgery for acute dissection of ascending aorta. Should the arch be included? J Thorac Cardiovasc Surg 1992;104:46–59.[Abstract]
- Fann JI, Smith JA, Miller DC, Mitchell RS, Moore KA, Grunkemeier G, Stinson EB, Oyer PE, Reitz BA, Shumway NE. Surgical management of aortic dissection during a 30-year period. Circulation 1995;92(Suppl):II113–II121.[Medline]
- Ehrlich MP, Ergin MA, McCullough JN, Lansman SL, Galla JD, Bodian CA, Apaydin A, Griepp RB. Results of immediate surgical treatment of all acute type A dissections. Circulation 2000;102(Suppl_3):248–252.
- Halstead JC, Meier M, Etz C, Spielvogel D, Bodian C, Wurm M, Shahani R, Griepp RB. The fate of the distal aorta after repair of acute type A aortic dissection. J Thorac Cardiovasc Surg 2007;133:127–135.[Abstract/Free Full Text]
- Westaby S, Saito S, Katsumata T. Acute type A dissection: conservative methods provide consistently low mortality. Ann Thorac Surg 2002;73:707–713.[Abstract/Free Full Text]
- Takahara Y, Sudo Y, Mogi K, Nakayama M, Sakurai M. Total aortic arch grafting for acute type A dissection: analysis of residual false lumen. Ann Thorac Surg 2002;73:450–454.[Abstract/Free Full Text]
- Kazui T, Washiyama N, Bashar AH, Terada H, Suzuki K, Yamashita K, Takinami M. Role of biologic glue repair of proximal aortic dissection in the development of early and mid-term redissection of the aortic root. Ann Thorac Surg 2001;72:509–514.[Abstract/Free Full Text]
- Yoshitatsu M, Nomura F, Katayama A, Tamura K, Katayama K, Ihara K, Nakashima Y. Pathologic findings of aortic redissection after glue repair of proximal aorta. J Thorac Cardiovasc Surg 2004;127:593–595.[Free Full Text]
- Kirsch M, Soustelle C, Houël R, Hillion ML, Loisance D. Risk factor analysis for proximal and distal reoperations after surgery for acute type A aortic dissection. J Thorac Caridovasc Surg 2002;123:318–325.[CrossRef]
- Lai DT, Miller DC, Mitchell RS, Oyer PE, Moore KA, Robbins RC, Shumway NE, Reitz BA. Acute type A aortic dissection complicated by aortic regurgitation: composite valve graft versus separate valve graft versus conservative valve repair. J Thorac Cardiovasc Surg 2003;126:1978–1986.[Abstract/Free Full Text]
- Kimura N, Tanaka M, Kawahito K, Yamaguchi A, Ino T, Adachi H. Influence of patent false lumen on long-term outcome after surgery for acute type A aortic dissection. J Thorac Cardiovasc Surg 2008;136:1160–1166.[Abstract/Free Full Text]
- Immer FF, Hagen U, Berdat PA, Eckstein FS, Carrel TP. Risk factors for secondary dilation of the aorta after acute type A aortic dissection. Eur J Cardiothorac Surg 2005;27:654–657.[Abstract/Free Full Text]
- Kazui T, Washiyama N, Muhammad BA, Terada H, Yamashita K, Takinami M, Tamiya Y. Extended total arch replacement for acute type A aortic dissection: experience with seventy patients. J Thorac Cardiovasc Surg 2000;119:558–565.[Abstract/Free Full Text]
- Uchida N, Ishihara H, Shibamura H, Kyo Y, Ozawa M. Mid-term results of extensive primary repair of the thoracic aorta by means of total arch replacement with open stent graft placement for an acute type A aortic dissection. J Thorac Cardiovasc Surg 2006;131:862–867.[Abstract/Free Full Text]
|
|
Top
Abstract
1. Introduction