Jessie J has revealed her heart condition may mean she has to mime some of her more challenging hits.

The 26-year-old singer – who recently called off the remainder of her Australian tour due to health problems – suffers from Wolff-Parkinson-White syn­­drome, which causes her to experience a fast, irregular heartbeat and shortness of breath, and can leave her feeling dizzy or faint.

According to the Daily Mirror, Jessie revealed in an interview given before she cancelled her tour, that doctors are worried about the strain put on her heart when she performs her songs, including Laserlight and Domino.

Jessie said: “I have prided myself in having got this far without having to lip sync but if my career carries on moving at the pace that it is, I will have to lip sync to be able to stay well.

“My songs are so big.”

Meanwhile, Jessie, a former coach on The Voice, has said that the judges on the BBC talent show have been too soft in the current series.

Jessie J was a coach on The Voice for two years (Joel Ryan/Invision)
Jessie J was a coach on The Voice for two years (Joel Ryan/Invision)

The Sweet Talker singer, who previously sang new judge Rita Ora’s praises, told The Times: “There are a few people who were told they were amazing that weren’t.

“No one turned around and afterwards one of the judges said, ‘It was so amazing, I can’t critique it.’ Well why didn’t you turn around? Because you’re lying.”