"It's bonkers what's happened over the past five years," says Kreena Dhiman from Crawley in West Sussex.
When diagnosed with breast cancer in 2013 at 33, she had just settled back into working life after getting married and spending a year backpacking round the world.
"I noticed one of my nipples was inverted and when I Googled for answers, I thought: 'Oh God, this can't be me.'"
Three years later, after surgery to remove one breast, chemotherapy, radiotherapy and another major reconstructive operation, Kreena felt she was out of the woods.
She had even arranged to have some of her eggs harvested, so that embryos could be created and frozen in case the cancer treatment made her infertile.
But then on a trip to Canada "to celebrate the end of my life with cancer", she felt grim.
She was tired, her chest was tight and she was struggling to breathe. Hospital doctors were baffled, until one cardiologist made a crucial link.
"He told me to squeeze his hand if I remembered having a red liquid during chemotherapy treatment," Kreena recalls.
She did. The diagnosis was acute heart failure and she was rushed to intensive care.
Heart damage risk
Thanks to advances in treatments, more patients than ever are surviving cancer – but one in 10 are developing serious heart conditions, sometimes soon after finishing treatment, others years later.
The problem is caused by chemotherapy drugs damaging the heart muscle, meaning it can no longer pump properly – and this can lead to heart failure.
It's even given rise to a new medical specialty called cardio-oncology, which focuses on delivering cancer treatments safely.
But working out which patients will get heart damage, and which won't, has proved really tricky up until now.
Scientists knew that the very young and the elderly were at high risk, but they've now found out that faulty genes also play a role in increasing risk in other people.
"Some have a gene to cause heart failure and they get a second hit from the chemo," explains Dr Alex Lyon, a consultant cardiologist at the Royal Brompton Hospital and Imperial College London.
"Most patients are told there's a small risk of heart problems."
A study of 200 cancer patients with cancer-therapy-induced cardiomyopathy, or CCM, has pinpointed the genetic risk factors, paving the way for testing of patients before they start chemotherapy to find out who is at risk.
The good news is that drug treatments can reduce the risk of heart damage in these patients and close monitoring can pick up potential problems early, Dr Lyon says.
'Pregnancy too dangerous'
Even patients like Kreena, who were left fighting for breath, can return to live a normal life.
"My recovery is incredible," she says. "I didn't think I'd be coming home."
During two weeks in a Canadian hospital, she sent voice messages back to relatives, preparing them for the worst.
After a two-month stay in the country on a no-salt diet and being cared for by her husband, her heart functioRead More – Source