READ: Dockless bike scheme to launch in LeedsWest Yorkshire Police were called when the woman who was caught, with her husband, in eastbound traffic caused by a collision between a van and a Vauxhall Astra car near junction one just before 8.30am called 999.
The woman had 50 minutes to make her operation appointment, and arrived in plenty of time after police transported her to hospital.
A West Yorkshire Police spokesperson said: "Female was stuck in heavy traffic with her husband on the M621 following a closure at Junction 1 for an earlier RTC.
READ: Leeds ‘recycled heat’ project could spark a revolution in cheap and efficient energy"She contacted us via 999 asking for assistance as had to be at the hospital in 50 minutes or the transplant would not go ahead. We dispatched our units to assist.
"The female was collected by our traffic unit and blue lighted to the hospital. Her husband continued the journey in his own vehicle. She arrived in plenty of time to receive treatment."
All lanes of the M621 re-opened around 10am although delays are thought to be felt all morning.