Use of recombinant activated factor VII for bleeding following resection of mediastinal angiosarcoma.

Sarcomatous lesions of the mediastinum usually present as aggressive and multicentre masses often attached to adjoining structures including heart and lungs. A forty one year male diagnosed with sarcomatous lesion in mediastinum presented for biopsy through midsternotomy later confirmed as angiosarcoma on histopathology. Patient bled excessively after surgery and required reopening of the chest. However, bleeding could not be controlled with reopening, blood products and packing of the mediastinal cavity. Bleeding could only be controlled by using recombinant activated factor VII as rescue therapy without any adverse effects.

Introduction

Angiosarcoma (AS) is an uncommon malignant neoplasm characterized by rapidly proliferating, extensively infiltrating anaplastic cells derived from blood vessels and lining irregular blood-filled spaces. AS of the mediastinum is a rare entity often undiagnosed preoperatively. Resection of the tumor often leads to extensive and refractory bleeding in perioperative period. Therefore, perioperative management of these tumours warrant special treatment. We present a case of AS of mediastinum that was managed with recombinant activated factor VII (rFVIIa) during postoperative period.

Case Report

A 41 years old male presented with chief complaint of gradual onset breathlessness on exertion New York Heart Association (NYHA) II and pain in right lower chest. There was no history of haemoptysis, orthopnea or paroxysmal nocturnal dyspnea. Pain in chest was dull in nature, non-radiating and relieved by taking medication. There was no history of hypertension, diabetes mellitus or any other prolonged illness.

There was no history of significant loss of weight and appetite.

On examination patient was conscious, cooperative and average built. His pulse rate was 78 per minute and blood pressure was 120/70 mmHg.

There was no significant respiratory distress at that time. Systemic examination revealed decreased air entry on auscultation at the lung bases.

Other systems were within normal limits. Routine blood investigations including complete blood count (CBC), renal and liver function tests were within normal limits. His coagulation profile including platelet count, prothrombin and activated partial thromboplastin time were also within normal limits.

Chest radiograph revealed bilateral pleural effusion that was later confirmed by ultrasonography of the chest.

Echocardiography revealed localized pericardial effusion adjacent to right atrium (RA) with multiple echodense nodular masses seen within pericardial cavity with constriction pathology.

There were significant respiratory variations across mitral and tricuspid valve. Inferior venacava (IVC) was dilated and collapsing less than 50% with inspiration. There was mild dilation of RA with no regional wall motion abnormality (RWMA). Computerized tomography (CT) scan thorax revealed large eccentric sarcomatous mass lesion, aneurysmal dilatation of RA and bilateral pleural effusion. Based on these results pleural tapping was done which revealed haemorrhagic fluid. Fibreoptic bronchoscopy was also done. Fine needle aspiration cytology (FNAC) and pleural cytology revealed no active malignant or inflammatory cells.

A provisional diagnosis of anterior mediastinal tumor was made and exploratory biopsy via midsternotomy was planned to confirm the diagnosis and informed consent was obtained for the same.

Patient was premedicated with lorazepam 2mg and pantoprazole 40 mg a night before the surgery. On arrival in the operating room, pulse oximetry revealed oxygen saturation of 96% on air. After securing venous access, radial artery cannulation was performed. Internal jugular vein cannulation was performed with trilumen catheter (7F). Anaesthesia was induced with sodium thiopentone (3 mg/kg) and fentanyl citrate (5 mcg/kg). Vecuronium bromide (0.15 mg/kg) was administered intravenously to facilitate tracheal intubation. Anaesthesia was maintained with intermittent doses of fentanyl citrate (1 mcg/kg), vecuronium bromide (0.02 mg/kg), and isoflurane in 50% oxygen in air.

Intraoperative monitoring included EKG with ST segment analysis, oxygen saturation, end tidal CO2, temperature and urine output, direct arterial blood pressure, central venous pressures, cardiac output and derived parameters, arterial blood gas analysis, and activated coagulation time (ACT). Transesophageal echocardiography (TEE) revealed large cavity around RA with communication with it and there was homogenous opacity inside the cavity.

Heparin sulphate 4 mg/kg was administered to maintain ACT more than 450 seconds before initiating cardiopulmonary bypass (CPB). Moderate hypothermia with cooling upto 28 °C was maintained. Total bypass time was 98 minutes. Aortic crossclamping was not done during dissection of the mass. A large necrotic vascular mass was seen in the anterior pericardium with invasion of RA and right ventricle. During dissection of the mass a rent in RA occurred which was repaired with bovine pericardial patch. Weaning from CPB was uneventful. Heparin was reversed with protamine monitoring the ACT.

A total of three units of packed red blood cells (PRBC) and four units of platelet concentrates (PC) and fresh frozen plasma (FFP) were transfused intraoperatively. Haemostasis was done however; patient was bleeding from the rough surgical surfaces. Tranexamic acid 10 mg/kg as bolus and 1 mg/kg/hr infusion was also started. Thereafter, mediastinum was packed with sponges and only skin layer was closed. Patient was shifted to the postoperative recovery room for mechanical ventilation and monitoring of haemodynamics and bleeding from chest drains.

In the recovery room patient was haemodynamically stable however constant bleeding was there from the mediastinum. He bled about 600ml in first and about 300 ml in next 24 hours. Echocardiography did not reveal any evidence of cardiac tamponade at that moment. He was planned for sternal closure on the second postoperative day after stabilisation of bleeding. However, during reopening significant oozing was still there from the surgical sites. Mediastinum was again packed with only skin closure and patient was shifted to the recovery room.

Histopathology of the mediastinal sample gave impression of angiosracoma with microscopic findings of highly vascular mitotically active spindle cell neoplasm composed of freely anastomosing vascular channels lined up by atypical cells.

He was haemodynamically stable in the postoperative period. However, constant bleeding from the chest drain was still there at 150-200 ml per day for next three days. On sixth postoperative day drainage was 40 ml in 24 hrs. Therefore, he was planned for removal of pack and secondary closure of the chest. During secondary closure, significant bleeding was still there from the raw surgical surface that was not controlled even by adequate haemostasis and electrocautry.

Thromboelastography (TEG) was within normal limits. A total of nine packed red blood cells, four units of fresh frozen plasma and four units of platelet concentrate and apheresis were transfused in the recovery room. Keeping in view of the intractable bleeding, massive transfusion and second reopening it was decided to administer rFVIIa (Novoseven, Novo Nordisk India Ltd) in the doses of 90 mcg/kg to this patient.

After administering recombinant factor seven oozing from the surgical surface settled down. Secondary closure of the chest was done and patient was shifted to the recovery room. Trachea was extubated after four hours and rest of the postoperative course was uneventful. After stabilization and discharge from the hospital patient was referred to oncology unit for further management and he is on a regular follow up for radiation therapy.

Discussion

Primary angiosarcomas of the anterior mediastinum are rare tumors that need to be considered in the differential diagnosis of primary anterior mediastinal neoplasms. Despite their histologic similarity to angiosarcomas at other sites, primary angiosarcomas of the anterior mediastinum appear to follow a more protracted clinical course than their counterparts in other organ systems [1].

Angiosarcomas tend to be aggressive and are often multicentric.

Approximately 50% of angiosarcomas occur in the head and neck. These tumors have a high local recurrence rate and metastasis because of their intrinsic biologic properties and because they are often misdiagnosed, leading to a poor prognosis and a high mortality rate. Malignant vascular tumors are clinically aggressive, difficult to treat, and have a reported 5-year survival rate of around 20% [2]. Some authors reported a mean survival of 14 months after diagnosis of angiosarcoma [3].

Primary heart tumours are extremely rare in clinical practice, occurring at a frequency of 0.11-0.30% in surgical series and only 25% of them are malignant. AS (75%) is the most common primary cardiac malignant tumor and is an extremely rare, rapidly spreading vascular tumor. It is seen more commonly in males than in females, usually presenting between the third and fifth decade of life.

Clinical presentation is usually unspecific and can vary depending on the dimension and the site of the tumour.

Increasing dyspnoea, peripheral oedema, superior venacava syndrome, lung oedema, arrythmia, weakness, syncope and dizziness are the most common symptoms. Potentially mortal complications are represented by pericardial effusion and thromboembolic events. AS are commonly located in the RA with a high incidence of pericardial involvement.

This predilection of the tumor affecting the right heart often produces right-sided congestive heart failure, superior vena cava obstruction and pericardial effusion [4,5]. In this case; the tumor was found arising from the RA presenting with pericardial effusion and symptoms of right heart failure. Imaging studies like chest radiograph, computerized tomography (CT) and magnetic resonance imaging (MRI) can reveal the extent and severity of tumor preoperatively. Echocardiography specially TEE confirms the intracardiac extent of the tumor and associated cardiac functions. Histopathology confirms the diagnosis and severity of the disease. Standard treatment includes extensive surgical resection followed by radio and chemotherapy to improve the survival as done in this case.

Perioperative management of these case warrant special care due to the presence of huge areas of necrosis and extensive loco-regional spread. Pre-operative histological diagnosis and careful evaluation of resectability is recommended.

Anaesthetic considerations in patients with tumor involving RA include hypoxemia, low cardiac output, possible right to left shunt, and potential pulmonary emboli. These patient’s symptoms can be exacerbated by changes in body position. Optimal anaesthetic management depends on the judicious administration of anaesthetics, avoidance of cardiac depression and maintenance of preload. Invasive haemodynamic monitoring and good venous access for rapid transfusion is necessary in these cases.

The primary problem in this case was refractory bleeding which was controlled even by reopening and adequate haemostasis. rFVIIa administered during second reopening helped in haemostasis and closure of chest.

rFVIIa (eptacog alpha activated) was introduced to clinical medicine in the 1980s as a prohemostatic agent. It is thought to act locally at the site of tissue injury and vascular wall disruption, by binding to exposed tissue factor and generating small amounts of thrombin that are sufficient to activate platelets.

The activated platelet surface can then form a template on which rFVIIa can directly or indirectly mediate further activation of coagulation, resulting in the generation of much more thrombin and, ultimately, fibrinogen to fibrin conversion. Clot formation is stabilized by inhibition of fibrinolysis, due to factor VIIa-mediated activation of thrombin-activatable fibrinolysis inhibitor [6].

Various authors have used rFVIIa safely as a rescue for refractory bleeding after cardiac surgery and found that it is associated with reduced blood loss, rapid improvement of coagulation variables, and decreased need for blood products [7,8,9,10].

Some authors reported use of rFVIIa in the setting of pulmonary haemorrhage secondary to chemotherapy for choriocarcinoma thereby preventing rapid deterioration in clinical condition and allowed salvage therapy [11]. It has also been used as rescue in bleeding associated with obstetrics, hepatic resection, trauma, intracerebral bleed and even dental extractions apart from coagulation disorders [12].

However, therapy with rFVIIa may lead to thromboembolic complications (10%) and the patient may not respond. This may lead to fatal complications.

Moreover, cost is also a limiting factor in its use.

A meta-analysis showed that, in 73% of patients, rFVIIa achieved a reduction of bleeding and the probability of survival increased. rFVIIa was not associated with an increased risk of thromboembolism compared with placebo [13].

However, data from 35 randomized controlled trials suggested that rate of arterial thromboembolic events is higher in patients who received rFVIIa than among those who received placebo (5.5% vs 3.2%, P=0.003) [14].

In the present case we have found significant reduction in bleeding after administering rFVIIa and secondary closure of the chest was possible. There was no evidence of any thromboembolic or other complications.

In conclusion, rFVIIa may be used as a rescue therapy in patients with malignant vascular tumors in the setting of intractable bleeding following surgical resection.