Muni Long underwent an emergency double lung transplant after she was given just one week to live.

The 37-year-old Grammy-winning R+B singer, who was diagnosed with lupus in 2014, was left stunned when she was told she needed surgery to keep her alive.

Speaking about being told she only had one week to live if she didn't undergo the transplant, she said on Good Morning America: "My jaw dropped. Literally.

"I was like, 'That's rude.' But they were kind of like, 'This is not a joke. You need to make a choice. You can either go to hospice or you can get these lungs.' "

Muni was initially concerned about how her voice might be affected by the op.

But, after being "faced with [her] own mortality", she thought about her three-year-old son, Tatum - who she has with ex-husband Raysean Hairston - and decided to go under the knife.

She added: "The ego and the vanity was just like, 'But what about my voice? What's going to happen?'.

"But then I look at my son, and I think about how much more life that I have to live. Quality of life was first.

"I can't sing if I'm not here."

Last year, Muni had to pull out of Brandy and Monica's The Boy Is Mine tour due to a bout of pneumonia, and she regrets taking on the tour.

She said: "I knew for a really long time that something was wrong. Every day I'm, like, spitting in cups and coughing all the time.

"Trying to take all these medicines to get through the day. With this industry, you're always in people's faces.

"So, I'm taking pictures, and I'm just huffing and puffing like I just ran a marathon.

"I should have never taken that tour. But there was so much going on in my life where I had to do it."

Despite her recent health scare, Long is now feeling "fabulous", but doctors warned her it might be six months to a year before she can perform again.

She said: "Tomorrow is my last appointment for all the things.

"No symptoms. Asymptomatic. No infections. None of that. Then I have my vocal check-up, six months will be in August because I had to have vocal surgery, as well."