Hemolytic Anemia Caused by Kinking of Dacron Grafts Implanted in Repair of after Aortic Dissection

Hemolytic anemia caused by kinked graft 6 months after aortic dissection repair

Background

Clinically insignificant hemolytic anemia is occasionally a complication of prosthetic valve replacement. However, hemolysis related to kinked grafts is a very rare complication after central repair for acute aortic dissection.

Case presentation

A 42-year-old man had undergone replacement of the ascending aorta and a root repair for type A aortic dissection 6 months previously. Laboratory data showed mild hemolysis 5 months later, and he began to complain of fatigue on exertion. The serum hemoglobin level reduced to 8.6 g/dL, and lactate dehydrogenase levels increased to 3071 IU/L with gross change in urine color, indicating hemoglobinuria. We diagnosed mechanical hemolytic anemia caused by a kinked graft and planned a repeat operation. The kinked graft was resected and graft-graft anastomosis was performed. Postoperatively, the clinical course was uneventful, and the hemolytic anemia completely resolved.

Conclusion

We herein report a case of hemolytic anemia caused by kinking of the graft 6 months after acute aortic dissection repair. The diagnosis was swiftly made, and the patient was successfully managed with redo surgery.

Hemolytic anemia caused by an excessively kinked prosthetic graft after total arch replacement detected by 4-dimensional flow magnetic resonance imaging: A case report

RATIONALE

Hemolytic anemia is a rare postoperative complication of aortic surgery, which may be caused by an excessively kinked graft that causes abnormal blood flow. It has been reported that 4-dimensional flow magnetic resonance imaging (4D flow MRI) can identify abnormal flow. Herein, we report the guidance of 4D flow MRI in performing the revision procedure for a patient with hemolytic anemia by evaluating abnormal blood flow based on this method.

PATIENT CONCERNS

A 70-year-old woman presented with dizziness and fatigue. She had undergone total arch replacement with a frozen elephant trunk 5 years prior. We diagnosed hemolytic anemia caused by a kinked graft after total arch replacement.

DIAGNOSIS

Although computed tomography findings revealed 3 lesions of the kinked graft at the ascending portion and cervical branches, 4D flow MRI findings showed that only the kinked graft at the ascending portion caused hemolytic anemia due to an elevated viscous energy loss around it.

INTERVENTION

We performed surgery to remove the kinked section instead of revision surgery consisting of total arch replacement.

OUTCOMES

The patient's postoperative course was uneventful and there were no complications. Postoperative enhanced computed tomography findings showed that the repaired graft had an adequate length and smoothly curved shape. The 4D flow MRI findings revealed smooth flow in the ascending portion and decreased viscous energy loss.

LESSONS

Based on the 4D flow MRI findings, we adopted a less invasive approach, repairing only the ascending portion of the graft, instead of performing revision surgery comprising total arch replacement.

Hemolysis following wrap aortoplasty for Type A aortic dissection repair: Case report and review of the literature

A Dacron wrap aortoplasty has been described as an adjunct to reduction ascending aortoplasty for the repair of Type A aortic dissections. We report a case of an uncomplicated hemiarch repair with wrap aortoplasty of the distal anastomosis which resulted in severe acute hemolysis. Despite only minimal focal graft deformation on imaging, the patient was found to have a flow gradient across the distal anastomosis, which was reduced by > 50% following release of the outer graft wrap. To our knowledge, only 29 additional cases of hemolytic anemia following aortic dissection repair have been described in the English literature. The reported mechanisms included aortic graft stenosis (50%), graft kinking (23%), external compression of the graft (20%), and a folded elephant trunk appendage (7%). The mean onset of hemolysis following aortic dissection repair occurred 32.2 ± 44.4 months after surgery, with only 16.7% of cases occurring within 2 weeks. This review details the clinical, laboratory, and imaging findings suggestive of mechanical hemolysis following aortic surgery.