Successful Endovascular Salvage of a Pancreatic Graft After a Venous Thrombosis: Case Report and Literature Review

Salvage Endovascular Thrombectomy for Splenic Vein Thrombosis After Pancreas Transplantation: A Single-Center Experience and Systematic Literature Review

OBJECTIVES

Technical graft loss, usually thrombotic in nature, accounts for most of the pancreas grafts that are removed early after transplant. Although arterial and venous thrombosis can occur, the vein is predominantly affected, with estimated overall rate of thrombosis of 6% to 33%. In late diagnosis, the graft will need to be removed because thrombectomy will not restore its functionality. However, in early diagnosis, a salvage procedure should be attempted.

MATERIALS AND METHODS

We conducted a retrospective, descriptive analysis of a prospective database of patients who underwent pancreas transplant from April 2008 to June 2020 at a single center. We evaluated post-transplant clinical glucose levels, imaging, treatment, and outcomes. We also performed a systematic review of publications for endovascular treatment of vascular graft thrombosis in pancreas transplant.

RESULTS

In 67 pancreas transplants analyzed, 13 (19%) were diagnosed with venous thrombus. In 7 of 13 patients (54%), systemic anticoagulation was prescribed because of a non-occlusive thromboses, resulting in complete resolution for all 7 patients. Six patients (46%) required endovascular thrombectomy because of the presence of complete occlusive thrombosis; 4 of these patients (67%) needed a second procedure because of recurrence of the thrombosis. One of the 6 patients (17%) required a surgical approach, resulting in successful removal of the recurrent clot. Twelve of the 13 grafts (92%) were rescued. Graft survival at 1 year was 84%; graft survival at 3, 5, and 10 years remained at 70%.

CONCLUSIONS

Pancreas vein thrombosis represents a frequent surgical complication and remains as a challenging problem. In our experience, early diagnoses and an endovascular approach combined with aggressive medical treatment and follow-up can be used for successful treatment and reduce graft loss.

Distal allograft pancreatectomy for graft salvage after pancreas transplantation

Early pancreas allograft failure most commonly results from vascular thrombosis. Immediate surgical intervention may permit pancreas allograft salvage, typically requiring thrombectomy. In cases of partial allograft necrosis secondary to splenic arterial thrombosis, distal allograft pancreatectomy may allow salvage of at least half of the pancreas allograft with retention of function. We retrospectively reviewed four cases of simultaneous pancreas and kidney recipients who required distal allograft pancreatectomy for splenic artery thrombosis with necrosis of the distal pancreas. Three of the four maintained long-term allograft function with euglycemia independent of insulin at six months to six years of follow-up, and all patients continue to maintain normal renal allograft function. Early diagnosis and early intervention are essential in order to salvage the pancreas allograft in the case of thrombosis. Distal allograft pancreatectomy can be performed safely and result in excellent long-term outcomes in select patients.

Early detection of complications in pancreas transplants by microdialysis catheters, an observational feasibility study

Background

Despite advances in immunosuppression and surgical technique, pancreas transplantation is encumbered with a high rate of complication and graft losses. Particularly, venous graft thrombi occur relatively frequently and are rarely detected before the transplant is irreversibly damaged.

Methods

To detect complications early, when the grafts are potentially salvageable, we placed microdialysis catheters anteriorly and posteriorly to the graft in a cohort of 34 consecutive patients. Glucose, lactate, pyruvate, and glycerol were measured at the bedside every 1–2 hours.

Results

Nine patients with graft venous thrombosis had significant lactate and lactate–to-pyruvate-ratio increases without concomitant rise in blood glucose or clinical symptoms. The median lactate in these patients was significantly higher in both catheters compared to non-events (n = 15). Out of the nine thrombi, four grafts underwent successful angiographic extraction, one did not require intervention and four grafts were irreversibly damaged and explanted. Four patients with enteric anastomosis leakages had significantly higher glycerol measurements compared to non-events. As with the venous thrombi, lactate and lactate-to-pyruvate ratio were also increased in six patients with graft surrounding hematomas.

Conclusions

Bedside monitoring with microdialysis catheters is a promising surveillance modality of pancreatic grafts, but differentiating between the various pathologies proves challenging.

Early protocol computer tomography and endovascular interventions in pancreas transplantation

BACKGROUND

Early vascular complications following pancreatic transplantation are not uncommon (3%-8%). Typically, cross-sectional imaging is requested in response to clinical change. We instituted a change in protocol to request imaging pre-emptively to identify patients with thrombotic complications.

METHODS

In 2013, protocol computer tomography angiography (CTA) at days 3-5 and day 10 following pancreas transplantation was introduced. A retrospective analysis of all pancreas transplants performed at our institution from January 2001 to May 2019 was undertaken.

RESULTS

A total of 115 patients received pancreas transplants during this time period. A total of 78 received pancreas transplant without routine CTA and 37 patients with the new protocol. Following the change in protocol, we detected a high number of subclinical thromboses (41.7%). There was a significant decrease in invasive intervention for thrombosis (78.6% before vs 30.8% after, p = .02), and graft survival was significantly higher (61.5% before vs 86.1% after, p = .04). There was also a significant reduction in the number of graft failures (all-cause) where thrombosis was present (23.4% before vs 5.6% after, p = .02). Patient survival was unaffected (p = .48).

CONCLUSIONS

Implementation of early protocol CTA identifies a large number of patients with subclinical graft thromboses that are more amenable to conservative management and significantly reduces the requirement for invasive intervention.