RT Journal Article SR Electronic T1 Pacemaker syndrome JF Heart JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 58 OP 58 DO 10.1136/heart.90.1.58 VO 90 IS 1 A1 Y Ahn A1 J G Cho YR 2004 UL http://heart.bmj.com/content/90/1/58.abstract AB