World number 11 Rory McIlroy revealed he had an "irregularity" with his heart that he would need to manage.
The Northern Irishman finished 2017 without a win – the first time he had failed to claim a tournament in a calendar year since 2008.
While McIlroy battled injuries last year, the 28-year-old revealed he also had a heart problem that he needed to keep an eye on.
"The rib's fine, no problems whatsoever – I had an MRI scan on my thoracic spine and all was OK. But I've got a bit of an irregularity with my heart that I have to keep on top of," he told The Telegraph.
"I have a flat T-wave and I'll have to get an echo [cardiogram] on my heart every six months and an MRI scan every year.
"I suffered a really bad viral infection in China 18 months ago and they told me that's the reason that I have this thickening of my left ventricle and there's a bit of scar tissue.
"For now, I just need to stay on top of it and have to stay fit. Hey, I was planning on doing that anyway."
A four-time major winner, McIlroy claimed the most recent of those at the 2014 US PGA Championship.
While he has slipped outside the top 10 in the rankings, McIlroy said his focus was purely on winning.
"It's nice to be world number one, sure, and I will get back there, but it's all about winning tournaments," he said.
"And I will give myself the best chances this season."
17 de marzo 2018
|England´s form continues to run cold in Twickenham snow|
|Nibali holds on in Milan-San Remo as Cavendish crashes again|
|Bournemouth 2 West Brom 1: Stanislas piles misery on Pardew|
|Buffon to play on for Italy as Di Biagio calls up uncapped duo|
|Huddersfield Town 0 Crystal Palace 2: Tomkins and Milivojevic secure priceless win|
|Stockdale makes history as ruthless Ireland win Grand Slam|
|Stoke City 1 Everton 2: Tosun at the double after Adam´s early dismissal|
|Simeone insists Atletico can survive injury crisis|
|Ireland´s Stockdale breaks Six Nations single campaign try record against England|
|Leipzig out to halt Bayern celebrations at Red Bull Arena|
|NFL Draft 2018: Jets acquire number three overall pick from Colts|
|Board accepts responsibility for West Ham woes, Brady claims|
|In-form Eriksen hopes he hasn´t hit Tottenham ceiling|
|Roma boss Di Francesco happy with Messi, Barca challenge|
|Bangladesh warned over ´unacceptable´ Colombo behaviour|
|The directors know where to find me - Gattuso awaits Milan talks|
|Laidlaw breaks Italian hearts in Rome|
|UMBC´s March Madness win earns everyone in USA free pizza|
|Zidane focused on Real Madrid players, not Neymar|
|Mourinho´s United rant recalls unhappy Madrid demise|
|Swansea City 0 Tottenham 3: Eriksen leads Kane-less Spurs into FA Cup semis|
|Valverde not worried about Barcelona legacy|
|Markelle Fultz´s return remains a mystery to Brett Brown|
|Bale is happy at Real Madrid, says Zidane|
|Spalletti seeks consistency as Inter prepare for final push|
|Absence of ´best in the world´ Busquets makes Rakitic key for Barca|
|I was out of the game - Halep offers no excuses for Osaka shock|
|Tigers spoil Slater´s 300th NRL game, wins for Penrith and Warriors|
|A-League Review: Sydney stumble again as Jets close gap|
|Highlanders claim derby win over Crusaders, Brumbies beat Sharks|
|Dreadshock! Neymar reveals new hairdo|
|Shakib and Nurul sanctioned for unruly Colombo conduct|
|Villarreal defender Semedo denied bail on attempted murder charge|
|Boots up! - Pietersen career seemingly over|
|Messi: I´m a less selfish player|
|F1 2018 Pre-Season Report: Williams|
|F1 2018 Pre-Season Report: Renault|
|Thunder claim key win, injury-ravaged Warriors fall to Kings|
|Japanese sensation Osaka blitzes Halep en route to decider|
|Giant-slaying Kasatkina upstages Venus to reach Indian Wells final|
|Coaching Italy would be extraordinary – Mancini|
|J.J. Watt breaks news of Tyrann Mathieu´s deal with Texans|
|Super Bowl champion LeGarrette Blount joins Lions|
|Intensity key to Liverpool toppling Man City, says Klopp|
|Warriors star Durant to miss at least two weeks with rib injury|
|Doc Rivers fined $15,000 for calling officiating ´complete joke´|
|Ravens sign WR Michael Crabtree to three-year deal|
|Tiger stumbles as Stenson and DeChambeau move clear|
|Tiger Woods: I just tried not to shoot myself out of tournament|
|Del Potro to meet Raonic in semis|
|People listen to idiots - Mourinho cites ´dictionary of life´ in extraordinary rant|
|Mourinho tells struggling Manchester United stars to ´grow up´|
|Woods seven off Bay Hill lead after level-par second round|
16 de marzo 2018
|Real Madrid links ´massage the ego´ of Roma goalkeeper Alisson|
|Defending champions Rhinos end Saints´ unbeaten start|
|Pele impressed by Tite´s ability to cope with Brazil´s modern challenges|
|Duhan at the double to boost Edinburgh´s playoff hopes|
|FIFA Council approves open vote for 2026 World Cup|
|McIlroy in love with golf again ahead of Augusta challenge|
|Vikings sign DT Sheldon Richardson|
|FIFA approves VAR use at World Cup|
|Sampaoli ignores Icardi and Dybala, adds Correa to Argentina squad|
|Vikings celebrate Cousins capture as AFC lags behind in NFL ´arms´ race|
|Neymar to Real Madrid? Ask Florentino Perez, says Emery|
|Pogba not as good as Kondogbia - Valencia boss Marcelino|
|Buffon: Most determined team will win Juventus-Madrid tie|
|Inter target Martinez likened to Aguero by Crespo|
|Dortmund boss Stoger defends Gotze criticism|
|Chaos in Colombo as Mahmudullah blasts Tigers into final|
|Filipe Luis relishes overcoming ´obstacle´ as broken leg rules him out for two months|