Forgotten human heart prompts Southwest flight to return to Seattle

SEATTLE — Southwest Airlines says a Dallas-bound flight returned to Seattle last weekend because a human heart was accidentally left onboard the plane.

The Seattle Times reports that Flight 3606 arrived in Seattle from Sacramento, California. Someone forgot to unload the heart before the plane left for Dallas, and the captain announced over Idaho they were turning back.

Southwest Airlines described the heart as a "life-critical cargo shipment." It was shipped by Sierra Donor Services in Sacramento.

The intended recipient of the heart, LifeNet Health Northwest in Renton, eventually did receive it in good condition once the plane returned to Sea-Tac. The company tells KOMO News that they were planning to recover valves from the heart for use in future transplant surgery. Parts of a heart, such as valves, can be recovered when whole heart transplants aren't feasible.

It wasn't immediately clear whose fault it was that the heart was left onboard the plane.

The flight took off for Dallas after a five-hour delay.