Former world No 1 Rory McIlroy has played down fears over his health after revealing he has a "slight heartbeat irregularity", insisting he is "fit and healthy" and ready to start his season at the Abu Dhabi HSBC Championship, presented by EGA, next week. McIlroy, 28, missed a large portion of the 2017 season with a rib injury and as a result slipped from No 2 in the world rankings to No 11 and failed to win a title. The Northern Irishman will begin his 2018 season at the Abu Dhabi HSBC Championship, starting January 15, where he is a four-time runner-up. In an interview with the <em>Daily Telegraph</em>, McIlroy said: "The rib's fine, no problems whatsoever - I had an MRI scan on my thoracic spin and all was OK. But I've got a bit of an irregularity with my heart that I have to keep on top of. <strong>_________________________________________________________</strong> <strong>Read more:</strong> <strong>_________________________________________________________</strong> "I have a flat T-wave and I'll have to get an echo [cardiogram] on my heart every six months and MRI scan every year." The revelation has, as McIlroy put it, caused a "big reaction" in the media as concerns surround his long-term future. However, the four-time major winner has since released a statement on Instagram downplaying any health fears. "Yesterday, I did an interview with the Daily Telegraph where I spoke about a range of topics regarding the last three months of my life," McIlroy wrote. "I touched upon a recent finding from a routine health and wellness check. Like anything, the deeper you dig the more likely you are to find something. It revealed I had a slight heartbeat irregularity called a flat or inverted T wave. "It's really not that big of a deal and nothing to worry about, apart from getting an annual check up, like you should do anyway. "I feel there's been a big reaction to it in the media which there really shouldn't be. I'm fit and healthy and can't wait to get my 2018 season started in Abu Dhabi next week." McIlroy will face stiff competition at the Abu Dhabi HSBC Championship from a field which includes world No 1 Dustin Johnson, Race to Dubai winner - and defending Abu Dhabi champion - Tommy Fleetwood, former British Open champion Henrik Stenson, and Olympic gold medallist Justin Rose. World No 14 Paul Casey and world No 15 Matt Kuchar will also be competing at the Abu Dhabi Golf Club.