A rare case of an expanded perigraft seroma with heart failure after thoracic aortic surgery

Abstract

Perigraft seroma (PS) is an occasional complication of abdominal and femoral aortic graft implantation. We report a rare case with heart failure due to expanded PS compressing the right atrium 5 years after ascending aorta replacement for an acute type A aortic dissection. The PS was drained and sealed with biological tissue adhesive and wrapped using bovine xenopericardial sheet. We believe that mild hemorrhage through a vascular graft caused the expanded PS. Furthermore, wrapping vascular grafts using bovine xenopericardial sheet after sealing with biological tissue adhesive was effective for PS, particularly in cases in which it is impossible to use greater omentum.

Learning objective

Cases of perigraft seroma (PS) after thoracic aortic repair have rarely been reported. The mechanism, indications, and treatments are unclear. We report a case of heart failure caused by expanded PS due to a small hemorrhage through a vascular graft. Furthermore, wrapping vascular grafts using bovine xenopericardial sheet after sealing with biological tissue adhesive may be effective for PS, particularly in cases where it is impossible to use the greater omentum.

Introduction

Although perigraft seroma (PS) is a rare complication after vascular surgery, an effective therapy has not yet been established. PS complicated with graft thrombosis, skin erosion, secondary graft infection, respiratory distress, and PS rupture was diagnosed in 16.4–18% patients after open abdominal aortic repairs [1], [2], [3]. However, PS after thoracic aortic repair is rarely reported [4], [5]. We report a case of heart failure caused by expanded PS after surgical treatment of the thoracic artery.

Case report

A 77-year-old woman was admitted to our hospital because of heart failure. She had a distal gastrectomy for gastric cancer at 68 years old. At 72 years old, she underwent replacement of the ascending aorta for an acute type A aortic dissection using a 26-mm woven graft (Gelweave, Termo, Tokyo, Japan); the native aorta did not cover the graft. One year postoperatively, subcutaneous effusion of the median sternotomy required serous fluid drainage. Follow-up computed tomography (CT) revealed low-density fluid collection around the graft (81 × 58 mm). On admission to our hospital, CT revealed an expanded PS around the graft (124 × 85 mm, 19.1 mean Hounsfield units) with the patchy contrast in the seroma and contrast effect on the pericardial adhesive surface, a compressed right atrium (RA), right pulmonary artery (RPA), and right pleural effusion (Fig. 1A, B, C). Transthoracic echocardiography (TTE) results were as follows: left ventricular end-diastolic dimension (LVEDD) = 41 mm, ejection fraction (EF) = 65%, left atrial dimension (LAD) = 36 mm, tricuspid regurgitation pressure gradient (TRPG) = 28 mmHg, and tricuspid annular plane systolic excursion (TAPSE) = 11 mm (Fig. 1D). There was no infection, although the patient had right pleural effusion, and blood sampling data revealed fibrinogen 649 mg/dL, aspartate aminotransferase (AST) 93 U/L; alanine aminotransferase (ALT), 139 U/L; total bilirubin, 0.8 mg/dL; and B-type natriuretic peptide, 227 pg/mL. We concluded that an expanded PS caused right heart failure and required drainage. Surgery was performed using femoro-femoral cardiopulmonary bypass, considering the possibility of a pseudoaneurysm. When the wall of the pseudoaneurysm was opened, there was serous fluid retention with blood absent. Fibrin clots were present around the graft (Fig. 2A). We judged that using her omental pedicle graft was impossible because of post distal gastrectomy. Wrapping vascular grafts using bovine xenopericardial sheet (bovine pericardial patch, Edwards, Irvine, CA, USA) after fibrin sealing of the outer graft surface using 5 mL of biological tissue adhesive (Bolheal, Chemo-sero-Therapeutic Research Institute, Kumamoto, Japan) was performed (Fig. 2B). Surgery was successful, and a subsequent CT scan revealed that the compressed RA and RPA had resolved (Fig. 2C, D). The postoperative blood sampling data were AST, 17 U/L; ALT, 10 U/L; total bilirubin, 0.5 mg/dL; and TTE results were: LVDd = 39 mm, EF = 71%, LAD = 32 mm, TRPG = 21 mmHg, and TAPSE = 15 mm. Pathological examination for PS revealed the presence of fibrin, fibroblasts, and platelets. The pericardial adhesive surface specimen contained an arterial epicardium and cholesterin granuloma. The postoperative course was uneventful. She was referred to and presented at another hospital without symptoms 1 year postoperatively.

Fig. 1.

Preoperative findings. (a) Contrast-enhanced CT shows an expanded perigraft seroma (PS) with low-density fluid collection around the ascending aortic graft. (b, c) Contrast-enhanced CT shows an expanded perigraft seroma around the graft-suppressed PA and RA (arrow) with right pleural effusion and contrast effect on the pericardial adhesive surface. The arrowhead highlights the patchy contrast in the seroma. Mean Hounsfield units of the patchy contrast was 56.4, that of the PS was 19.1, and 169 for the aorta. (d) Transthoracic echocardiography shows that the RA and RV are compressed (arrowhead).

Ao, aorta; PA, pulmonary artery; RA, right atrium; RV, right ventricle; CT, computed tomography.

Fig. 2.

Intraoperative pictures. (a) There was no notable anastomotic, graft bleeding, or hematoma in the operative field, but a dark-brown fluid around the graft was observed intraoperatively. The enlarged view shows the peri-grafting tissue and fibrin of the outside grafting surface. (b) Wrapping using bio-prosthetic pericardium. (c) Transthoracic echocardiography shows that the RA returned to normal. (d) Ten days postoperatively, the expanded perigraft seroma around the graft had vanished.

Ao, aorta; PA, pulmonary artery; RA, right atrium; RV, right ventricular.

Discussion

PS is an unusual complication after vascular graft implantation, including abdominal aortic aneurysm repair, axillo-femoral, and femoro-femoral bypass [1], [3], [4]. Kadakol et al. [2] defined PS as a perigraft fluid that occurred more than 3 months postoperatively, with a diameter of >3 cm and < 25 Hounsfield units on CT imaging. The incidence of PS was 16.4–18% after open abdominal aortic repair. In contrast, cases of PS after thoracic aortic repair have been rarely reported and the incidence has been unknown [4], [5]. Studies reported that PS developed more frequently in patients with expanded polytetrafluoroethylene (23.9%) compared with polyester grafts (3.8%) [2], [3]. The mechanism of PS is unclear; however, it has been linked to immunologic response, low-grade infection, fibroblast inhibition, coagulation abnormalities, and fluid leakage through the graft [6].

A polyethylene terephthalate graft was used in this case, and there was no significant anastomotic or graft bleeding and hematoma in the operative field. We focused on the healing process after vascular grafting. The preoperative CT findings revealed a patchy contrast in the seroma and a contrast effect on the pericardial adhesive surface. The impermeability of the graft depends on the porosity of the fibrin matrix and fabric. The fibrin matrix is a cross-linked fibrin structure formed on the inner surface of the graft and the peri-grafting tissue of the outer surface during the healing process. If the peri-grafting tissue does not form, the impermeability of the graft depends on the porosity of the fabric. Regarding the patchy contrast in the seroma and contrast effect on the pericardial adhesive surface, the mean CT Hounsfield units for contrast aorta was 169, and the patchy contrast of seroma was higher (56.4) and closer to blood components than PS (19.1) (Fig. 1). Shiiya et al. [7] reported a case of peri-graft hematoma due to trans-graft hemorrhage after thoracic aorta replacement with a polyethylene terephthalate prosthesis. Contrast-enhanced CT revealed characteristic patchy contrast extravasation outside the graft, which was not found to be anastomotic or graft tear bleeding. He suggested that the bleeding might have resulted from inadequate peri-grafting-tissue and trans-graft hemorrhage [8]. Murata et al. [9] also reported that some proteins in the patient's blood inhibit fibroblast development and unstable fibrin. Some proteins contained in the tissue components of small trans-graft seroma may be one of the reasons for the expanded PS. Therefore, we thought that the mild hemorrhage that leaked through the porous structure of the vascular graft may have contained unstable fibrin and tissue components, and this may have caused fluid retention and contributed to preventing the formation of peri-grafting-tissue around the graft because the intraoperatively collected PS contents were mainly fibrin and fibroblasts.

Indications and methods for treating PS have not been established; however, treatment is required when symptoms appear [6]. Some reported treatment options for PS include drainage, sealing with fibrin glue, replacement with another graft type, omental implantation, and stent-graft placement [1], [4], [5]. We thought stable fibrin and tissue components were needed around the graft and omental implantation after sealing with fibrin was effective. But, it was impossible in this case to use her omental pedicle graft due to post distal gastrectomy. We performed wrapping vascular grafts using bovine xenopericardial sheet after sealing with biological tissue adhesive. Bovine xenopericardial sheet treated with glutaraldehyde, reported to be less prone to infection, was the best material [10]. Bolheal is a biological tissue adhesive composed of human fibrinogen, antihemophilic factor XIII fraction, aprotinin solution, thrombin, and calcium chloride hydrate. Thrombin activates fibrinogen into fibrin, and factor XIII stabilizes fibrin. Aprotinin inhibits plasmin from fibrin degradation. A stable fibrin clot induces the proliferation of fibroblasts and the production of collagen fibers and granulation matrix components, thereby promoting tissue repair. Bolheal was suitable as a biological tissue adhesive.

In the future, re-expansion of the PS may recur; therefore, we should continue careful observation of patients and explore other solutions.

Conclusion

We reported a case of expanded PS caused by heart failure due to mild hemorrhage through a vascular graft. Wrapping vascular grafts using bio-prosthetic pericardium after sealing with biological tissue adhesive may be effective for PS, particularly in cases where the use of omental pedicle graft was impossible.

Informed consent

The patient provided informed consent.

Funding

None.

Declaration of competing interest

All authors declare that they have no conflicts of interest.