A beauty therapist who was clinically dead for 30 minutes after suffering a cardiac arrest in bed was saved by her pet dog who howled for help . Joanna Mellor , 24 , went into cardiac arrest after going to sleep next to her boyfriend Andrew Rayment , 27 . Upon discovering she was n't breathing , the couple 's five-year-old pet Labrador , Leo , began barking . This woke Mr Rayment , who hurriedly dialled 999 and performed CPR on his girlfriend until paramedics arrived . Scroll down for video . Joanna Mellor , 24 , suffered a cardiac arrest in her sleep , but her five-year-old dog Leo barked until her boyfriend woke up and realised she was n't breathing . Leo barked until Miss Mellor 's boyfriend Andrew woke up . Andrew dialled 999 and performed CPR on his girlfriend until paramedics came and she was rushed to hospital for life-saving treatment . In hospital , doctors said her heart had stopped for 30 minutes before Mr Rayment began CPR . She was able to make a full recovery after her cardiac arrest , something paramedics said is unheard of . Incredibly , doctors said Miss Mellor 's heart had stopped for 30 minutes before Mr Rayment managed to resuscitate her . Miss Mellor , who lives with her boyfriend in Ilkeston , Derbyshire , has since been diagnosed with Wolff-Parkinson-White ( WPW ) syndrome . This is a condition in which she has an extra electrical connection in the heart , causing it to beat abnormally fast , triggering a cardiac arrest . Miraculously , she has now made a full recovery . She said : ' I owe my life to my dog and my boyfriend . If Leo had n't woken Andrew up I might not be here today . ' I remember going to bed and drifting off the sleep and the next I know I 'm in intensive care in hospital and told I 'd suffered a heart attack . 'The doctors say I was technically dead because it took Andrew 30 minutes to get my heart started . 'Andrew said he woke up with Leo barking and jumping up at my side of the bed and going mad . 'He says he could tell something was wrong with me and dialled 999 and the operator talked him through CPR . 'At first the doctors said I might be at risk of brain damage and I could n't feel my legs and one of my hands was all limp but I 've now made a full recovery . ' Miss Mellor now says she 'owes her life ' to her labrador Leo and her boyfriend Andrew Rayment , 27 . Miss Mellor 's Wolff-Parkinson-White ( WPW ) syndrome had meant her heart began beating irregularly . This caused a cardiac arrest , where the electrical activity of the heart becomes so chaotic that the heart stops pumping and quivers of 'fibrillates ' instead . The heart stops pumping blood around the body , causing a person to lose consciousness and potentially die within minutes . Mr Rayment said he woke up to barking on January 2nd this year . He said : ' I was half asleep when Leo woke me up . ' I heard Joanna 's breathing becoming erratic and I tried to wake her and tapped each side of her face , but she was unconscious so I called 999 . 'My first thought was that I did n't want to waste the paramedics ' time but when I was on the phone her breathing went from in and out to every few seconds . ' I tried not to panic and to stay focused . I kept thinking that the only chance she has relies on me doing the CPR properly . ' Rescue crews from East Midlands Ambulance Service dashed to the scene in under 15 minutes before rushing her to the Queen 's Medical Centre in Nottingham . Paramedic Glenn Radford said : ' I 've been on the job for 14 years and I 've never seen anything like it . 'When people suffer cardiac arrests , quite often they are left with neurological problems . They do n't usually make a 100 per cent recovery . '
Joanna Mellor went to sleep and suffered a potentially fatal cardiac arrest . Her pet Labrador , Leo , barked until her boyfriend woke up and dialled 999 . She was rushed to hospital where she was clinically dead for 30 minutes . Was able to make a miraculous recovery - and says Leo saved her life .