Reportedly, Sir Paul McCartney underwent heart surgery last fall - he had coronary angioplasty which is a procedure that opens up arteries and produces a greater blood flow. 

A source close to the former Beatle said, "Paul had been complaining about not feeling well and saw a Harley Street specialist at The London Clinic."

"Tests were carried out and the decision was taken to operate.  Paul had the angioplasty in a private hospital.  It was all very routine but any work on your heart is a big deal," the source added.

McCartney has made a good recovery, as he joined pop princess Kyle Minogue on stage to perform his hit single 'Dance Tonight'.

The insider added, "Luckily Paul is in very good shape.  He does regular exercise and is fit.  He eats well and does not carry any excess weight.  He has always been in exceptional health, which is remarkable when you think of the rock 'n' roll lifestyle he once had."

A rep for Sir Paul has confirmed the surgery last fall.  "It was a routine medical operation."

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