JP Morgan upgraded St. Jude Medical (STJ

) to overweight from neutral.

Analyst Michael Weinstein says St. Jude is his top pick in the Medical Products sector for 2003, and he sees an appreciation potential of 50% or greater in the next 12 months. Weinstein set a $55 year-end 2003 target, which is 26 times his raised $2.10 2004 earnings per share estimate, up from $2.05.

Weinstein views St. Jude as a 2004 growth acceleration story as the company joined in on the rapidly growing cardiac resynchronization market, particularly for high voltage devices, which in 2004 he expects to exceed $1.2 billion. He says every point of the Cardiac Resynchronization Therapy Defibrillators (CRT-D) market share gain in 2004 should translate in $0.015 in incremental earnings per share.

Weinstein also raised his $2.40 2005 earnings per share estimate to $2.50.