After nearly two months of tango-ing and cha-cha-ing for Dancing with the Stars, Wayne Newton figured he'd waltz right through a stress test last month. But after the singer, 65, hopped off his doctor's treadmill, he was stunned by his diagnosis: a recurrence of cardiomyopathy, a serious disease that affects the heart muscle. Prescription: no more dancing for a while. "I told him, 'You've got to be kidding!'" Newton says, sitting in the study at his sprawling horse ranch in Las Vegas. "It didn't occur to me I'd be faced with something like this."

The performer dubbed "Mr. Las Vegas" successfully battled the same disorder six years ago, after falling ill following a USO tour in Afghanistan, and had been feeling fine since. But his doctors told him that the disease has caused an irregular heartbeat that could lead to a heart attack if he overexerts himself. Ordered to take it easy for six to eight weeks, Newton wanted to keep performing, but his wife, Kathleen, 43, mother of their daughter Lauren, 5, drew the line. "She said, 'If you die, who is going to raise Lauren?'" So Newton canceled his two-month gig at Harrah's in Las Vegas and says he'll appear at Dancing's Nov. 27 finale alongside other eliminated contestants but won't dance: "It's like sprinting—you have to go full out." He plans to appear on the upcoming Dancing tour to croon some tunes ("I could truly do that falling out of bed") and maybe emcee. "He doesn't want to disappoint people," says Kathleen. "It means so much to him that the show will go on."

For the singer there's more to life than the stage. "We have a boat on Lake Mead, I raise Arabian horses, and I fly a helicopter," says Newton. "When people quit what they love to do, that's the end. And sitting around doing nothing is the hardest thing for me."

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