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Efficiency of Transluminal Angioplasty of Hepatic Venous Outflow Obstruction in Pediatric Liver Transplantation
Efficiency of Transluminal Angioplasty of Hepatic Venous Outflow Obstruction in Pediatric Liver Transplantation K.-T. Lu, Y.-F. Cheng, T.-Y. Chen, L.-C. Tsang, H.-Y. Ou, C.-Y. Yu, H.-W. Hsu, W.-X. Lim, Y.-S. Tong, and T.-L. Huang* Department of Diagnostic Radiology and Liver Transplantation Program, Chang Gung Memorial Hospital Kaohsiung Medical Center, Kaohsiung, Taiwan
ABSTRACT Background. Our aim in this study was to evaluate long-term efficiency of hepatic venous balloon angioplasty (BA) and stent placement (SP) for hepatic venous outflow obstruction (HVOO) in pediatric liver transplantation (LT). Methods. From January 1999 to September 2016, 262 pediatric patients underwent LT at our hospital. Ten were diagnosed with HVOO, which included 8 living donor grafts and 2 split liver grafts. BA and SP were used in management of these 10 patients with HVOO. After intervention, Doppler ultrasound (DUS) was the major follow-up modality for comparing efficiency of BA and SP. Results. The incidence of HVOO was 3.8% (10 of 262) in our pediatric LTs. Of the 10 HVOO cases, 5 had SP, 3 had BA once, 1 had BA twice, and 1 had BA twice along with SP. The patent hepatic vein was maintained after a mean follow-up of 7.4 (range, 0.04e17) years. Recurrent rate of HVOO after BA was 42%. Neither recurrent HVOO nor stent migration occurred after SP and throughout long-term follow-up. Conclusion. Hepatic venous SP was found to be more effective and safe than BA for treatment of HVOO in pediatric LT for long-term follow-up.
H
EPATIC venous outflow obstruction (HVOO) after liver transplantation (LT) is an uncommon complication. The frequency of HVOO in orthotopic LT has been reported to be approximately 1.5%e2.5% [1,2]. However, the incidence of HVOO in pediatric LT has been reported at 4%e9%, which is higher than in adult LT [3e6]. Transluminal angioplasty, including balloon angioplasty (BA) and stent placement (SP), are accepted treatments in patients with HVOO because of the effectiveness and minimal invasiveness [7,8]. The purpose of this study was to evaluate retrospectively the long-term results of transluminal angioplasty for HVOO after pediatric LT. MATERIALS AND METHODS Patients From January 1999 to September 2016, a total of 262 pediatric patients, consisting of 132 boys and 130 girls, received LT at the Kaohsiung Chang Gung Memorial Hospital, Taiwan. Patients’ age was 2.94 3.5 years (mean SD) and body weight (BW) was 11 7.5 kg (mean SD). ª 2018 Published by Elsevier Inc. 230 Park Avenue, New York, NY 10169
Transplantation Proceedings, 50, 2715e2717 (2018)
Diagnosis and Decision for Management HVOO was first suspected by clinical signs and symptoms, such as massive ascites, pleural effusion, and elevated liver enzymes. Doppler ultrasound (DUS) was used for evaluation. If weak hepatic venous flow (<10 cm/s) and a persistent flattening hepatic venous waveform were observed, then we performed computed tomography angiography for diagnosis of HVOO, with a criterion of >50% stenosis when compared with the proximal hepatic vein (HV). We then performed venography and manometry for reconfirmation, with a criterion of >50% stenosis and >5 mm Hg pressure gradient across the stenosis between the HV and inferior vena cava (IVC).
This work was supported by grants from the Ministry of Science and Technology, ROC (103-2314-B-182A-007 and 1042314-B-182A-094). *Address correspondence to Tung-Liang Huang, MD, Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Niao-Sung, Kaohsiung 833, Taiwan. E-mail: [email protected] 0041-1345/18 https://doi.org/10.1016/j.transproceed.2018.04.022
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LU, CHENG, CHEN ET AL
Management We performed transluminal angioplasty immediately after reconfirmation of HVOO. Two types of transluminal angioplasty were defined: BA and SP. BA was performed with a 7F percutaneous transluminal angioplasty catheter, with a balloon diameter of 6e10 mm and a length of 20 mm. The diameter of the balloon was based on the HV proximal to stenosis site. The balloon was inflated for 1 minute with an atmospheric pressure of 10 atm. All stents were self-expanding metallic stents with a diameter of 10e14 mm and length of 40 mm.
DUS Follow-up Postintervention After intervention, DUS was conducted by radiologist for follow-up once per day in the intensive care unit, once a week in the ordinary ward, and every 6 months in the outpatient department.
showed normal biphasic or triphasic after intervention. Significant clinical symptoms improvement, such as decreased ascites or pleural effusion, was achieved in all patients. Stent Placement
A total of 6 patients underwent metallic SP for treatment. Stents were 10, 12, or 14 mm in diameter (4 patients received a 10-mm-diameter stent, 1 received a 12-mmdiameter stent, and 1 received a 14-mm-diameter stent) and 4 cm in length. The patent period of hepatic venous outflow after SP was 4.4 6.25 years (mean SD). No one developed recurrent HVOO after SP. Balloon Angioplasty
RESULTS
Of the total 262 pediatric patients, 10 patients were diagnosed with HVOO. Incidence was 3.8% for all 262 pediatric LTs. Of the 10 patients, mean age was 3.6 (range, 0.4e8) years, and mean BW was 12.6 (range, 5e20) kg. The median interval between the LT and onset of HVOO was 1.75 (range, 0e36) months. Mean follow-up was 7.4 (range, 0.04e17) years. BW at last follow-up was 36.8 24.6 kg (mean SD). Of the 10 patients, 5 underwent SP, 3 underwent BA once, 1 underwent BA twice, and 1 underwent BA twice in addition to SP. Table 1 shows the long-term results of patients with transluminal angioplasty. Technique success was achieved in all patients. Doppler ultrasound showed marked increase in hepatic venous velocity from a mean 20.2 cm/s before intervention to 54.4 cm/s after intervention. Waveform data
A total of 7 sessions of BA were performed in 5 patients. Two of the 5 patients underwent BA twice due to recurrent HVOO. The patent period of hepatic venous outflow after BA was 6.7 6.5 years (mean SD). There were no intervention-related complications after BA. Recurrence Rate
A total of 13 sessions of transluminal angioplasty were performed in 10 patients, including 6 sessions of SP in 6 patients and 7 sessions of BA in 5 patients. No one developed recurrent HVOO after SP. Three recurrent HVOO events after 7 sessions of BA were noted. The recurrence rate of HVOO after SP was 0% and the recurrence rate of HVOO after BA was 43%. There was a higher recurrent rate for BA than SP over the mean follow-up period of 7.4 years.
Table 1. Outcomes of Transluminal Angioplasty Age Body (years) Gender Weight (kg)
Original Disease
Stent placement 0.5 Female 5.6 Biliary atresia 1 Male 7.9 Biliary atresia 3 Female 8.2 Biliary atresia 3 Male 8.7 Hemangioendothelioma 7 Male 20 Biliary atresia Balloon angioplasty once 3 Female 13.4 Glycogen storage disease 5 Female 16 Glycogen storage disease 8 Male 25 Neonatal hepatitis Balloon angioplasty twice 2 Female 9.1 Biliary atresia
Type of Endovascular Venoplasty, mm (diameter length)
Velocity and Waveform of HV Before Venoplasty
Velocity and Waveform of HV After Venoplasty
Patent Period
Last Body Weight (kg)
40 40 40 40 40
Empty flow in V3 6 cm/s, irregular 17 cm/s, monophasic 10 cm/s, monophasic 8 cm/s, monophasic
88.7 cm/s, triphasic 40.2 cm/s, biphasis 26.4 cm/s, triphasic 81 cm/s, biphasic 103 cm/s, biphasic
3 years 3 years 2 years 2 weeks 17 years
15 15.3 14.3 11 62
Balloon 8 20
18 cm/s, monophasic
43 cm/s, biphasic
13 years
57.2
Balloon 8 20
23 cm/s, monophasic
32 cm/s, biphasic
12 years
72
Balloon 8 20
61 cm/s, monophasic
81 cm/s, biphasic
8 years
47
14 cm/s, monophasic; 32 cm/s, monophasic
31 cm/s biphasic; 66 cm/s, biphasic
19 days 14 years
59
37 cm/s, monophasic; 10 cm/s, monophasic; 28, cm/s monophasic
33 cm/s, biphasic; 40 cm/s, biphasic; 42 cm/s, biphasic
2 weeks 1 month 1.5 years
15
Stent Stent Stent Stent Stent
10 10 10 10 12
Balloon 8 20, balloon 10 20 Balloon angioplasty twice and additional stent placement 3 Female 14 Biliary atresia Balloon 10 20, balloon 10 20, stent 14 40 Abbreviation: HA, hepatic vein.
TRANSLUMINAL ANGIOPLASTY
Longest Follow-up Period
One boy received a 12 40-mm metallic stent placement into the left hepatic vein after diagnosis of HVOO when he was 7 years old. Postintervention DUS showed normal velocity and a biphasic waveform. Ascites decreased significantly postintervention. After a 17-year follow-up, BW increased from 20 to 62 kg and hepatic venous outflow maintained patency, which was the longest follow-up period among all patients. There was no intervention-related complication, such as stent migration or intravascular thrombosis. First Documented Intraoperative Hepatic Venous Stent Placement
A 5-month-old girl with a BW of only 5.6 kg was the first documented recipient to undergo intraoperative hepatic venous SP. After venous surgical reconstruction during the transplant operation, DUS showed empty flow in segment 3 HV with thrombosis inside. We then immediately performed intraoperative venography using a transliver surface approach and total obstruction of segment 3 HV was diagnosed. After deployment of a metallic stent (10 40 mm) cover segment 3 HV to IVC, venography showed a patent segment 3 HV. After a 3-year follow-up, the segment 3 HV maintained patency. DISCUSSION
The incidence of HVOO in pediatric LTs has been reported at 4.5%e9% [3e6]. In our case study, the incidence was 3.8%, lower than in previously reported data, owing to the donor graft hepatic venoplasty technique used at our hospital. In left-lobe grafts, venoplasty consisting of the left HV and adjacent veins, such as the left superior vein, middle HV, or segment 3 vein, is performed to create a single, wide orifice without compromising outflow for anastomosis with the recipient’s vena cava [9]. The possible causes in the early posttransplantation period of HVOO include direct compression or twisting of the venous anastomosis by inappropriate graft size or tight sutures. The late posttransplant period of HVOO may be secondary to intimal hyperplasia and fibrotic change at the site of the anastomosis [7]. In our study, the 1.75-month onset period of HVOO after LT may be due to intimal hyperplasia and fibrotic change at the site of the anastomosis. In the long-term results, with a mean of 7.4 years of follow-up, there was a higher recurrence rate for BA than SP. Thus, we believe SP is a more effective treatment for HVOO than BA in pediatric LT for long-term survival. The major complications of hepatic venous SP include stent migration and intravascular thrombosis. Yabuta et al [6] reported a complication of HV stent (4-cm length and 10-mm diameter) migrating to the right atrium in a 5-yearold boy. The stent was then removed via surgical sternotomy and right atrial incision. Ultimately, the patient needed retransplantation due to hepatic venous thrombosis. However, in our study, there was no stent migration or
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intravascular thrombosis seen after 4.4 6.25 years of follow-up. Our results demonstrate that hepatic venous SP can be safe for pediatric LT for long-term survival. In addition, one 7-year-old boy had SP (4-cm length and 12-mm diameter) for the 17-year follow-up, without any complications. Thus, a stent 4 cm in length and 12 mm in diameter is appropriate for a 7-year-old boy with a BW increasing from 20 to 62 kg. HVOO in pediatric LT had a significant impact on patient and graft survival. Early intervention may improve the graft survival [10]. In our study, we performed intraoperative SP for one 5-month-old girl, with graft function continuing to remain normal at <3-year follow-up. We believe it is better for graft survival to commence outflow patency as early as possible. DUS was found to be the best imaging technique for follow-up after transluminal angioplasty. It is a readily available and noninvasive technique and is effective for detection of HVOO. DUS can detect hepatic venous outflow abnormalities immediately during LT, and then intraoperative early intervention can be performed to reduce liver damage as much as possible. CONCLUSION
SP was found to be more safe and effective than BA for HVOO in pediatric LTs for long-term survival. REFERENCES [1] Navarro F, Le Moine MC, Fabre JM, et al. Specific vascular complications of orthotropic transplantation with preservation of the retrohepatic vena cava: review of 1361 cases. Transplantation 1999;68:646e50. [2] Parrilla P, Sanchez-Bueno F, Figueras J, et al. Analysis of the complications of the piggy-back technique in 1,112 liver transplants. Transplantation 1999;67:1214e7. [3] Miraglia R, Maruzzelli L, Caruso S, et al. Interventional radiology procedures in pediatric patients with complications after liver transplantation. Radiographics 2009;29:567e84. [4] Cheng YF, Chen CL, Huang TL, et al. Angioplasty treatment of hepatic vein stenosis in pediatric liver transplants: long-term results. Transpl Int 2005;18:556e61. [5] Berrocal T, Parron M, Alvarez-Luque A, et al. Pediatric liver transplantation: a pictorial essay of early and late complications. Radiographics 2006;26:1187e209. [6] Yabuta M, Shibata T, Shibata T, et al. Long-term outcome of percutaneous interventions for hepatic venous outflow obstruction after pediatric living donor liver transplantation: experience from a single institute. J Vasc Interv Radiol 2013;24:1673e81. [7] Carnevale FC, Machado AT, Moreira AM, et al. Midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation. J Vasc Interv Radiol 2008;19:1439e48. [8] Akun E, Yaprak O, Killi R, et al. Vascular complications in hepatic transplantation: single-center experience in 14 years. Transplant Proc 2012;44:1368e72. [9] Concejero A, Chen CL, Wang CC, et al. Donor graft outflow venoplasty in living donor liver transplantation. Liver Transpl 2006;12:264e8. [10] Egbert S, Paul M, Elisabeth M, et al. Early vascular complications after pediatric liver transplantation. Liver Transpl 2000;6: 326e32.
ABSTRACT Background. Our aim in this study was to evaluate long-term efficiency of hepatic venous balloon angioplasty (BA) and stent placement (SP) for hepatic venous outflow obstruction (HVOO) in pediatric liver transplantation (LT). Methods. From January 1999 to September 2016, 262 pediatric patients underwent LT at our hospital. Ten were diagnosed with HVOO, which included 8 living donor grafts and 2 split liver grafts. BA and SP were used in management of these 10 patients with HVOO. After intervention, Doppler ultrasound (DUS) was the major follow-up modality for comparing efficiency of BA and SP. Results. The incidence of HVOO was 3.8% (10 of 262) in our pediatric LTs. Of the 10 HVOO cases, 5 had SP, 3 had BA once, 1 had BA twice, and 1 had BA twice along with SP. The patent hepatic vein was maintained after a mean follow-up of 7.4 (range, 0.04e17) years. Recurrent rate of HVOO after BA was 42%. Neither recurrent HVOO nor stent migration occurred after SP and throughout long-term follow-up. Conclusion. Hepatic venous SP was found to be more effective and safe than BA for treatment of HVOO in pediatric LT for long-term follow-up.
H
EPATIC venous outflow obstruction (HVOO) after liver transplantation (LT) is an uncommon complication. The frequency of HVOO in orthotopic LT has been reported to be approximately 1.5%e2.5% [1,2]. However, the incidence of HVOO in pediatric LT has been reported at 4%e9%, which is higher than in adult LT [3e6]. Transluminal angioplasty, including balloon angioplasty (BA) and stent placement (SP), are accepted treatments in patients with HVOO because of the effectiveness and minimal invasiveness [7,8]. The purpose of this study was to evaluate retrospectively the long-term results of transluminal angioplasty for HVOO after pediatric LT. MATERIALS AND METHODS Patients From January 1999 to September 2016, a total of 262 pediatric patients, consisting of 132 boys and 130 girls, received LT at the Kaohsiung Chang Gung Memorial Hospital, Taiwan. Patients’ age was 2.94 3.5 years (mean SD) and body weight (BW) was 11 7.5 kg (mean SD). ª 2018 Published by Elsevier Inc. 230 Park Avenue, New York, NY 10169
Transplantation Proceedings, 50, 2715e2717 (2018)
Diagnosis and Decision for Management HVOO was first suspected by clinical signs and symptoms, such as massive ascites, pleural effusion, and elevated liver enzymes. Doppler ultrasound (DUS) was used for evaluation. If weak hepatic venous flow (<10 cm/s) and a persistent flattening hepatic venous waveform were observed, then we performed computed tomography angiography for diagnosis of HVOO, with a criterion of >50% stenosis when compared with the proximal hepatic vein (HV). We then performed venography and manometry for reconfirmation, with a criterion of >50% stenosis and >5 mm Hg pressure gradient across the stenosis between the HV and inferior vena cava (IVC).
This work was supported by grants from the Ministry of Science and Technology, ROC (103-2314-B-182A-007 and 1042314-B-182A-094). *Address correspondence to Tung-Liang Huang, MD, Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, 123 Ta-Pei Road, Niao-Sung, Kaohsiung 833, Taiwan. E-mail: [email protected] 0041-1345/18 https://doi.org/10.1016/j.transproceed.2018.04.022
2715
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LU, CHENG, CHEN ET AL
Management We performed transluminal angioplasty immediately after reconfirmation of HVOO. Two types of transluminal angioplasty were defined: BA and SP. BA was performed with a 7F percutaneous transluminal angioplasty catheter, with a balloon diameter of 6e10 mm and a length of 20 mm. The diameter of the balloon was based on the HV proximal to stenosis site. The balloon was inflated for 1 minute with an atmospheric pressure of 10 atm. All stents were self-expanding metallic stents with a diameter of 10e14 mm and length of 40 mm.
DUS Follow-up Postintervention After intervention, DUS was conducted by radiologist for follow-up once per day in the intensive care unit, once a week in the ordinary ward, and every 6 months in the outpatient department.
showed normal biphasic or triphasic after intervention. Significant clinical symptoms improvement, such as decreased ascites or pleural effusion, was achieved in all patients. Stent Placement
A total of 6 patients underwent metallic SP for treatment. Stents were 10, 12, or 14 mm in diameter (4 patients received a 10-mm-diameter stent, 1 received a 12-mmdiameter stent, and 1 received a 14-mm-diameter stent) and 4 cm in length. The patent period of hepatic venous outflow after SP was 4.4 6.25 years (mean SD). No one developed recurrent HVOO after SP. Balloon Angioplasty
RESULTS
Of the total 262 pediatric patients, 10 patients were diagnosed with HVOO. Incidence was 3.8% for all 262 pediatric LTs. Of the 10 patients, mean age was 3.6 (range, 0.4e8) years, and mean BW was 12.6 (range, 5e20) kg. The median interval between the LT and onset of HVOO was 1.75 (range, 0e36) months. Mean follow-up was 7.4 (range, 0.04e17) years. BW at last follow-up was 36.8 24.6 kg (mean SD). Of the 10 patients, 5 underwent SP, 3 underwent BA once, 1 underwent BA twice, and 1 underwent BA twice in addition to SP. Table 1 shows the long-term results of patients with transluminal angioplasty. Technique success was achieved in all patients. Doppler ultrasound showed marked increase in hepatic venous velocity from a mean 20.2 cm/s before intervention to 54.4 cm/s after intervention. Waveform data
A total of 7 sessions of BA were performed in 5 patients. Two of the 5 patients underwent BA twice due to recurrent HVOO. The patent period of hepatic venous outflow after BA was 6.7 6.5 years (mean SD). There were no intervention-related complications after BA. Recurrence Rate
A total of 13 sessions of transluminal angioplasty were performed in 10 patients, including 6 sessions of SP in 6 patients and 7 sessions of BA in 5 patients. No one developed recurrent HVOO after SP. Three recurrent HVOO events after 7 sessions of BA were noted. The recurrence rate of HVOO after SP was 0% and the recurrence rate of HVOO after BA was 43%. There was a higher recurrent rate for BA than SP over the mean follow-up period of 7.4 years.
Table 1. Outcomes of Transluminal Angioplasty Age Body (years) Gender Weight (kg)
Original Disease
Stent placement 0.5 Female 5.6 Biliary atresia 1 Male 7.9 Biliary atresia 3 Female 8.2 Biliary atresia 3 Male 8.7 Hemangioendothelioma 7 Male 20 Biliary atresia Balloon angioplasty once 3 Female 13.4 Glycogen storage disease 5 Female 16 Glycogen storage disease 8 Male 25 Neonatal hepatitis Balloon angioplasty twice 2 Female 9.1 Biliary atresia
Type of Endovascular Venoplasty, mm (diameter length)
Velocity and Waveform of HV Before Venoplasty
Velocity and Waveform of HV After Venoplasty
Patent Period
Last Body Weight (kg)
40 40 40 40 40
Empty flow in V3 6 cm/s, irregular 17 cm/s, monophasic 10 cm/s, monophasic 8 cm/s, monophasic
88.7 cm/s, triphasic 40.2 cm/s, biphasis 26.4 cm/s, triphasic 81 cm/s, biphasic 103 cm/s, biphasic
3 years 3 years 2 years 2 weeks 17 years
15 15.3 14.3 11 62
Balloon 8 20
18 cm/s, monophasic
43 cm/s, biphasic
13 years
57.2
Balloon 8 20
23 cm/s, monophasic
32 cm/s, biphasic
12 years
72
Balloon 8 20
61 cm/s, monophasic
81 cm/s, biphasic
8 years
47
14 cm/s, monophasic; 32 cm/s, monophasic
31 cm/s biphasic; 66 cm/s, biphasic
19 days 14 years
59
37 cm/s, monophasic; 10 cm/s, monophasic; 28, cm/s monophasic
33 cm/s, biphasic; 40 cm/s, biphasic; 42 cm/s, biphasic
2 weeks 1 month 1.5 years
15
Stent Stent Stent Stent Stent
10 10 10 10 12
Balloon 8 20, balloon 10 20 Balloon angioplasty twice and additional stent placement 3 Female 14 Biliary atresia Balloon 10 20, balloon 10 20, stent 14 40 Abbreviation: HA, hepatic vein.
TRANSLUMINAL ANGIOPLASTY
Longest Follow-up Period
One boy received a 12 40-mm metallic stent placement into the left hepatic vein after diagnosis of HVOO when he was 7 years old. Postintervention DUS showed normal velocity and a biphasic waveform. Ascites decreased significantly postintervention. After a 17-year follow-up, BW increased from 20 to 62 kg and hepatic venous outflow maintained patency, which was the longest follow-up period among all patients. There was no intervention-related complication, such as stent migration or intravascular thrombosis. First Documented Intraoperative Hepatic Venous Stent Placement
A 5-month-old girl with a BW of only 5.6 kg was the first documented recipient to undergo intraoperative hepatic venous SP. After venous surgical reconstruction during the transplant operation, DUS showed empty flow in segment 3 HV with thrombosis inside. We then immediately performed intraoperative venography using a transliver surface approach and total obstruction of segment 3 HV was diagnosed. After deployment of a metallic stent (10 40 mm) cover segment 3 HV to IVC, venography showed a patent segment 3 HV. After a 3-year follow-up, the segment 3 HV maintained patency. DISCUSSION
The incidence of HVOO in pediatric LTs has been reported at 4.5%e9% [3e6]. In our case study, the incidence was 3.8%, lower than in previously reported data, owing to the donor graft hepatic venoplasty technique used at our hospital. In left-lobe grafts, venoplasty consisting of the left HV and adjacent veins, such as the left superior vein, middle HV, or segment 3 vein, is performed to create a single, wide orifice without compromising outflow for anastomosis with the recipient’s vena cava [9]. The possible causes in the early posttransplantation period of HVOO include direct compression or twisting of the venous anastomosis by inappropriate graft size or tight sutures. The late posttransplant period of HVOO may be secondary to intimal hyperplasia and fibrotic change at the site of the anastomosis [7]. In our study, the 1.75-month onset period of HVOO after LT may be due to intimal hyperplasia and fibrotic change at the site of the anastomosis. In the long-term results, with a mean of 7.4 years of follow-up, there was a higher recurrence rate for BA than SP. Thus, we believe SP is a more effective treatment for HVOO than BA in pediatric LT for long-term survival. The major complications of hepatic venous SP include stent migration and intravascular thrombosis. Yabuta et al [6] reported a complication of HV stent (4-cm length and 10-mm diameter) migrating to the right atrium in a 5-yearold boy. The stent was then removed via surgical sternotomy and right atrial incision. Ultimately, the patient needed retransplantation due to hepatic venous thrombosis. However, in our study, there was no stent migration or
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intravascular thrombosis seen after 4.4 6.25 years of follow-up. Our results demonstrate that hepatic venous SP can be safe for pediatric LT for long-term survival. In addition, one 7-year-old boy had SP (4-cm length and 12-mm diameter) for the 17-year follow-up, without any complications. Thus, a stent 4 cm in length and 12 mm in diameter is appropriate for a 7-year-old boy with a BW increasing from 20 to 62 kg. HVOO in pediatric LT had a significant impact on patient and graft survival. Early intervention may improve the graft survival [10]. In our study, we performed intraoperative SP for one 5-month-old girl, with graft function continuing to remain normal at <3-year follow-up. We believe it is better for graft survival to commence outflow patency as early as possible. DUS was found to be the best imaging technique for follow-up after transluminal angioplasty. It is a readily available and noninvasive technique and is effective for detection of HVOO. DUS can detect hepatic venous outflow abnormalities immediately during LT, and then intraoperative early intervention can be performed to reduce liver damage as much as possible. CONCLUSION
SP was found to be more safe and effective than BA for HVOO in pediatric LTs for long-term survival. REFERENCES [1] Navarro F, Le Moine MC, Fabre JM, et al. Specific vascular complications of orthotropic transplantation with preservation of the retrohepatic vena cava: review of 1361 cases. Transplantation 1999;68:646e50. [2] Parrilla P, Sanchez-Bueno F, Figueras J, et al. Analysis of the complications of the piggy-back technique in 1,112 liver transplants. Transplantation 1999;67:1214e7. [3] Miraglia R, Maruzzelli L, Caruso S, et al. Interventional radiology procedures in pediatric patients with complications after liver transplantation. Radiographics 2009;29:567e84. [4] Cheng YF, Chen CL, Huang TL, et al. Angioplasty treatment of hepatic vein stenosis in pediatric liver transplants: long-term results. Transpl Int 2005;18:556e61. [5] Berrocal T, Parron M, Alvarez-Luque A, et al. Pediatric liver transplantation: a pictorial essay of early and late complications. Radiographics 2006;26:1187e209. [6] Yabuta M, Shibata T, Shibata T, et al. Long-term outcome of percutaneous interventions for hepatic venous outflow obstruction after pediatric living donor liver transplantation: experience from a single institute. J Vasc Interv Radiol 2013;24:1673e81. [7] Carnevale FC, Machado AT, Moreira AM, et al. Midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation. J Vasc Interv Radiol 2008;19:1439e48. [8] Akun E, Yaprak O, Killi R, et al. Vascular complications in hepatic transplantation: single-center experience in 14 years. Transplant Proc 2012;44:1368e72. [9] Concejero A, Chen CL, Wang CC, et al. Donor graft outflow venoplasty in living donor liver transplantation. Liver Transpl 2006;12:264e8. [10] Egbert S, Paul M, Elisabeth M, et al. Early vascular complications after pediatric liver transplantation. Liver Transpl 2000;6: 326e32.