Thrombolysis of portal vein thrombosis after splenectomy following liver transplantation

Abstract

Splenectomy is indicated after orthotopic liver transplantation (OLT) for various reasons, including left-sided portal hypertension, trauma, and hemorrhage prevention in patients with splenic artery aneurysms. Complications of splenectomy may include infections, bleeding, and portal vein thrombosis (PVT). The incidence of symptomatic postsplenectomy PVT ranges from 0.7% to 2%,1, 2 whereas the incidence of asymptomatic PVT can reach 7% to 10%.3 There is, however, limited literature pertaining to postsplenectomy PVT in recipients of OLT. The sequelae of PVT are particularly serious in OLT recipients. The reduction of the portal vein flow severely compromises allograft and patient survival.4, 5 In patients who have not undergone OLT, acute portal or mesenteric vein thrombosis is usually managed with anticoagulation alone, and this leads to recanalization in more than 90% of patients.6 Alternatively, thrombolysis or thrombectomy is performed, but this has not been widely reported and is not the standard of care.7 There are few studies addressing the management of postsplenectomy PVT in OLT recipients. Here we describe a case of acute postsplenectomy PVT in an OLT recipient who was successfully treated with both mechanical thrombolysis and directed and systemic anticoagulation. The patient was a 54-year-old male who suffered from end-stage liver disease secondary to complications from hepatitis C and alcohol abuse. He underwent OLT on March 5, 2007. The piggyback technique was used with a biliary duct-to-duct anastomosis. The operation and the postoperative course both went well without complications. Approximately 2 years later, he presented with increasing left upper quadrant pain. A computed tomography (CT) scan revealed an enlarged spleen with a calcified cyst that measured 17 cm. Therapeutic options were discussed with the patient, and splenectomy was planned. He received subcutaneous heparin perioperatively as deep venous thrombosis prophylaxis. The operation lasted 2 hours and was performed through an extension of the left subcostal incision from the initial OLT. An Endo GIA stapler was used to divide the hilum. Pathology revealed a 960-g spleen measuring 18.2 cm × 14.3 cm × 10.2 cm with capsular fibrosis indicating perisplenitis. Postoperative laboratory tests revealed a 5-fold rise in transaminase levels. An ultrasound examination of the liver was performed and revealed an absence of flow in the portal vein. Dual-phase CT of the liver showed complete thrombosis of the splenic and portal veins with extension into both right and left portal vein branches. The superior mesenteric vein was spared. An intravenous infusion of heparin was initiated. Complete thrombosis of the intrahepatic portal vein branches precluded percutaneous transhepatic cannulation of the portal system. The patient was taken immediately to the operating room in an attempt to salvage the hepatic allograft. A peripheral mesenteric venous branch was located and cannulated with a 5-Fr Fogarty catheter. An initial portogram confirmed the CT finding and revealed complete thrombosis of the main portal vein with some residual flow within the intrahepatic branches (Fig. 1A). Thrombectomy of the main portal vein was attempted via the catheter. With the assistance of interventional radiology, an infusion catheter was placed. Tissue plasminogen activator (t-PA) was injected through the catheter at a rate of 2.5 mg every 15 minutes. After the administration of a total of 16 mg of t-PA, only partial recanalization of the main portal vein was achieved (Fig. 1B). The catheter was withdrawn, the venotomy was ligated, and the abdomen was closed. The patient was extubated and then monitored in the intensive care unit. A postoperative ultrasound examination demonstrated no flow in the portal system. A follow-up CT scan revealed a filling defect in the portal vein and throughout the splenic vein. Interventional radiology was reconsulted, and the patient was taken to the angiography suite. This time, through a right internal jugular vein puncture, the right hepatic vein was cannulated, and the portal vein was accessed transhepatically. The portogram revealed thrombosis of the splenic vein stump, the main portal vein, and the intrahepatic portal veins extending beyond the bifurcation. The superior mesenteric vein was spared. A Trellis 8 pharmacomechanical thrombolysis device (Bacchus Vascular, Santa Clara, CA) was introduced into the portal vein. A total dose of 10 mg of t-PA was administered over 10 minutes, and mechanical thrombolysis was performed simultaneously from the portal confluence to the portal bifurcation. The device was then repositioned between the portal confluence and the inferior mesenteric vein, and another cycle of thrombolysis was undertaken with an additional 8 mg of t-PA. A subsequent portogram revealed significant improvement of the flow in the portal system, with residual thrombus in the splenic vein stump extending only along the medial wall of the main portal vein (Fig. 2A). A low-rate thrombolytic infusion of t-PA and heparin was administered overnight in an attempt to resolve the residual thrombus (0.5 mg/hour via an infusion catheter extending from the splenic vein stump to the main portal vein and 200 U/hour via a transjugular sheath in the main portal vein). The next day, the patient was taken back to the angiography suite, and a portogram revealed a patent portal vein with minimal residual nonocclusive thrombi in the main and right portal veins (Fig. 2B). A repeat ultrasound examination demonstrated recanalization of the portal venous system. Follow-up ultrasound examinations were performed 1 and 2 weeks after the procedure, and all revealed patent vessels. The transaminasemia returned to normal over a period of 5 days after splenectomy. The patient was maintained on a heparin infusion and was converted to warfarin for a total of 6 months after the procedure. The patient did well in the 3 years following this procedure with good allograft function, and portal vein patency was maintained, as demonstrated by follow-up imaging. This case demonstrates that mechanical and directed thrombolysis via a transjugular, transhepatic approach can be both safe and effective. It may represent another viable option when open thrombectomy is neither feasible nor effective. This is, however, only a single case. In order to determine the best therapeutic measures for this type of complication, multicenter experiences and studies are warranted. Lloyd Brown, M.D.1 Ahmad Abou Abbass, M.D.1 Shunji Nagai, M.D.1 Vrishali Patil, M.D.1 Marwan Abouljoud, M.D.1 Todd Getzen, M.D.2 Atsushi Yoshida, M.D.1 Marwan Kazimi, M.D.1 Dean Y. Kim, M.D.1 Divisions of 1Transplant and Hepatobiliary Surgery and 2Interventional Radiology Henry Ford Hospital Detroit, MI