Medtronic Inc., Minneapolis, expects to merge the $100 million in pension assets of Physio International Control Corp. into its nearly $1.3 billion in pension plans by May 1, said Robert Moe, senior benefits manager for Physio. Medtronic acquired Physio of Redmond, Wash., in September. INVESCO, the sole manager for Physios $70 million defined benefit plan, and manager of a balanced fund for its $30 million defined contribution plan, will be terminated. Mr. Moe, who declined to say if there were other managers for its defined contribution plan, did say INVESCO is the only manager change that will take place. Vanguard will take over the INVESCO accounts. It is the sole manager for Medtronics $800 million 401(k) plan and runs a large-cap U.S. equity portfolio for its $224 million defined benefit plan. The remaining $267 million are in an ESOP. Dale Beumer, vice president and treasurer for Medtronic, declined to discuss current managers for its defined benefit plan or any possible manager changes. Wurts & Associates, consultant to Physio, will be terminated. Jeffrey Slocum & Associates, which assisted Medtronic with the merger, will be retained.