Vansummeren, who is in the final year of his contract at Ag2r La Mondiale, was withdrawn in Oman before stage three after an irregularity was discovered with his heart and the Belgian is undergoing tests in his homeland to get to the root of the problem.
His team’s medical director Eric Bouvat told media at Paris-Nice that Vansummeren will only return to competition when he is healthy enough to do so, which could be weeks, or even months.
“Vansummeren is undergoing various examinations in Belgium,” Bouvat said. “Only after weeks, perhaps months, can we have an indication of what exactly is going on and when he would be allowed to resume.
“There’s not much more I can say at this time. With a broken arm, you know that someone is on the sidelines for six weeks, but with the heart, you have to be careful.
“Everything should be investigated and you especially do not take risks. What is now important is the health of Johan.”
Vansummeren, 35, is hopeful of returning before the end of the season and could struggle to win a new contract if he is kept out of action all year.