Approved Research

Genome-wide association study regarding impaired venous patency after insertion into arterial circulation

Lay summary

The use of a patient's vein to substitute the function of a diseased artery - a so called bypass - is a frequently performed procedure in heart and vascular surgery. Additionally, veins are routinely connected to arteries in the arm and sometimes the leg - a so called arteriovenous fistula - to generate a vascular access for hemodialysis required in patients suffering from end stage chronic kidney disease. In both cases veins are inserted into arterial circulation which subjects veins to higher blood pressure and more pulsatile flow compared regular venous circulation. This requires efficient remodeling of the venous wall.

A major complication after these procedures is a subsequent reduction of vein diameter (venous stenosis). This can be a consequence of both blood clotting or overly active remodeling of the inner wall to sustain the higher blood pressure.

Venous stenosis impairs blood flow, frequently requires interventions and worst case can lead to the failure of the bypass or arteriovenous fistula. The possibility to identify patients at elevated risk could assist in developing optimized treatment and follow-up protocols. For example, in case of peripheral bypass surgery the use of prosthetic vessels is a possible alternative to a patient's own veins. Additionally, patients at elevated risk of venous stenosis might also benefit from being examined at short frequency intervals to identify and treat complications early.

Previously, single genes and their variants have been linked to venous stenosis after both bypass and fistula surgery. However, no investigation so far combined both and conducted a comprehensive analysis of the complete genetic background (a patient's genome). Thereby, we also aim to investigate whether the presence of multiple gene variants associated with venous stenosis has additive effects on the risk.

The estimated project duration is up to 36 months.