- Donald withdraws from RSM Classic with chest pains
- Former world No. 1 taken to hospital for seven hours of tests
- Englishman will not return to the game until 2018
The Englishman, 39, had been preparing to play in this week's RSM Classic at Sea Island Golf Club in Georgia.
But he was forced to withdraw on Thursday and was taken to South East Georgia Brunswick hospital for a series of precautionary heart tests.
"Well that wasn't quite the finish to my year I had in mind!!" Donald posted on his Instagram page.
"Had some chest pain last night and into this morning and it kept getting worse. After some medical advice, I had to withdraw and was shipped off to the hospital to get my heart looked at.
"After seven hours of tests all looks good with my heart thankfully. A big thank you to the staff at the South East Georgia Brunswick hospital for taking good care of me.
"Time to put my feet up for a few weeks, recharge, regroup and get ready for a big 2018."
Donald, a five-time winner on the PGA Tour, topped the Official World Golf Rankings for the first time in May 2011 -- a position he held for a cumulative total of 56 weeks.
He had been due to partner Americans Matt Kuchar and Brandt Snedeker for the first two rounds at the $6 million event.