Image 1 of 5 Johan Vansummeren apologised after breaking his bike in the big stage 3 crash Image 2 of 5 Belgian's Johan Vansummeren and Jan Bakelants (Image credit: Frédéric Machabert / AG2R La Mondiale Pro Cycling Team) Image 3 of 5 Alexis Vuillermoz and Johan Vansummeren embrace after the Frenchman won stage 8 at the Tour de France (Image credit: Tim de Waele/TDWSport.com) Image 4 of 5 Johan Vansummeren and Domenico Pozzovivo (Ag2r) (Image credit: Tim de Waele/TDWSport.com) Image 5 of 5 Lunch time for Johan Vansummeren of Ag2r (Image credit: Tim de Waele/TDWSport.com)

Former Paris-Roubaix winner Johan Vansummeren (AG2R-La Mondiale) will not race the opening weekend of the Classics due to a heart problem, according to reports from the Belga news agency. Vansummeren had previously stated that he would not ride this weekend as he didn't feel well and 'had no power' in his legs.

The heart problem was initially discovered last month during a training camp in Granada but Vansummeren was cleared to race. He made his debut at the Tour of Qatar and went on to race the Tour of Oman but pulled out after stage two on the request of the team doctors. It is not known how long Vansummeren will be out for and he will now undergo tests to understand the full extent of the problem.

"On the first hand, I am really disappointed because the Classics were one of my main season's objectives," Vansummeren said in a statement released by the team. "But on the other hand, we are talking about heart defects, therefore it is essential to do additional examinations. I do not want to take any risks because I need to be as healthy as possible to start competition again. I hope to be quickly reassured and, evidently, to ride with AG2R La Mondiale team roster again during this season."

The Classics are set to kick off this weekend with Omloop Het Nieuwsblad and Kuurne-Brussel-Kuurne. Vansummeren is a veteran of the Classics and won Paris-Roubaix in 2011. Should he race this year's edition he is expected to be one of the leaders for the AG2R-La Mondiale team.

"Johan is a real fighter and a reliable rider," said AG2R-La Mondiale general manager Vincent Lavenu. "We will give him our full support in these humanly painful moments. We really wish to see him wearing AG2R-La Mondiale team's jersey again soon."

In recent years there have been a string of riders that have had to pull out of racing or retire entirely due to heart problems. Most recently Michael Rogers had to delay his season opener because of his heart and when he did finally get racing he was forced to pull out after just two stages.

Vansummeren's former teammate and Tour of Flanders winner Nick Nuyens had to retire due to an issue with his heart, as did former cyclo-cross world champion Niels Albert. In 2014, Dutchman Robert Gesink underwent surgery on his heart after he was diagnosed with cardiac arrhythmia.

"We have to pay special attention to Johan Vansummeren's case," said Eric Bouvat, AG2R-La Mondiale medical director. "We can assure you every possible effort will be made to protect him. His health is our top priority."