MTV.com reports that the reunited VAN HALEN have been forced to postpone four upcoming dates of their U.S. tour due to an unspecified medical condition affecting guitarist Eddie Van Halen. A statement issued by tour promoter Live Nation on Monday afternoon (March 3) explained that concerts in Dallas, Cincinnati, Baltimore and Raleigh, North Carolina, have been postponed and rescheduled for April."According to Eddie Van Halen's physician, he is undergoing a battery of comprehensive medical tests to determine a defined diagnosis and recommended medical procedures," read the release. The March 3 show at American Airlines Arena in Dallas has been rescheduled for April 24; the March 5 show at U.S. Bank Arena in Cincinnati has been moved to April 22; the March 7 show at RBC Center in Raleigh was shifted to April 13 and the March 9 show at 1st Mariner Arena in Baltimore will now take place April 15, according to Pollstar. Fans should retain their tickets as they will be honored at the rescheduled concerts or ticket refunds will be issued at the original point of purchase. The Live Nation spokesperson said the tour is expected to pick up the previously scheduled dates beginning on March 11 in Charlottesville, Virginia, and, for now, no other dates have been affected.