Jeremy Corbyn said it was "incredibly sad" after a woman died days after describing being left in hospital without treatment for hours.
The Labour Leader said Jayne Rae's "life ended as she lived it: making the world a better place."
The 53-year-old had a "passion for defending our NHS and making sure it's there for everyone whenever they need it", said Mr Corbyn.
In a video first shared by Mr Corbyn on Sunday, Labour campaigner Ms Rae told of arriving for hospital treatment to find a scene that "looked like Beirut".
"I have never seen people lying in corridors covered in blood, dying, doctors under stress, nurses unable to help to the point of they were crying in frustration."
Ms Rae, from Whittle-le-Woods in Lancashire, described tearfully how her mother was "begging" staff to save her life after she spent several hours waiting for treatment in "extreme pain".
Following news of her death on Monday morning after a year with terminal breast cancer, Mr Corbyn tweeted his tribute and added that "Jayne sent me this video" which showed her passion for defending the NHS.
Last week, Ms Rae's daughter posted pictures to Facebook of a bunch of red roses sent by the Labour leader, along with a note reading: "Dear Jayne, thank you for all you do helping others. We will build a world of care for all. With our love and support, Jeremy x."
Ms Rae had previously received media attention after holding a "last" birthday party in July to raise money for local community projects, including the hospital and hospice where she has been treated.
RIP Jayne became the top trend on Twitter on Monday afternoon as others paid tribute to the campaigner.
Twitter user @LuckyHeronSay wrote: "RIP Jayne. Vote Labour on the NHS people. People deserve better than this heartless Tory shower."
Paul Connolly wrote: "RIP Jayne a fighter for justice to the very last. You were a credit to your family, your friends, country and the Labour movement. My sincere condolences to Jaynes family, you can be very proud of her."
Karen Doyle wrote: "Rest in Peace Jayne. We will continue your work to make this country a better place for all. Much love to your friends and family. They have lost a diamond."
@moomadee1 wrote: "I have the same terminal secondary cancer as Jayne.
"We're living under a cloud of death, we are in dire need of help.
"If I'd been seen sooner after my original diagnosis, it wouldn't have had the time to spread, and i wouldnt be waiting to die."
Source: Read Full Article