Hemolytic anaemia due to graft kinking progression and aortic stenosis exacerbation after aortic arch replacement: A case report.

INTRODUCTION

Hemolytic anaemia from graft kinking is a rare complication after aortic surgery, typically treated by graft replacement. This case highlights hemolytic anaemia caused by the interaction of aortic stenosis and a kinked graft, successfully managed with transcatheter aortic valve replacement (TAVR).

PRESENTATION OF CASE

A 75-year-old male developed hemolytic anaemia 2 years after total aortic arch replacement for a saccular aneurysm, with a worsening graft kink and aortic stenosis. Phase-contrast MRI confirmed abnormal blood flow at the kink. Due to his frail condition from prostate cancer, TAVR was performed, resolving the anaemia.

DISCUSSION

Factors contributing to graft kinking include intraoperative graft length determination, natural aortic elongation with ageing, and graft type. To determine the cause of hemolysis, we needed to evaluate whether it was due to the kinked graft, aortic stenosis, or their combined effect. Hemolytic anaemia appeared at a low pressure gradient of 15.5 mmHg across the aortic valve, making it unlikely that the valve alone was the cause of the hemolysis. Using phase-contrast cardiovascular magnetic resonance, we observed abnormally accelerated blood flow caused by aortic stenosis impinging on the kinked graft. Possible causes include an increased pressure gradient at the kink due to accelerated blood flow, as well as physical collisions that may have resulted in shear stress on the red blood cells.

CONCLUSION

TAVR resolved hemolytic anaemia caused by aortic stenosis and graft kinking after aortic arch replacement. In high-risk patients, less invasive treatment of the primary condition may effectively resolve hemolytic anaemia.