Small-cap stocks mostly underperformed the rest of the market Wednesday thanks to disappointing first-quarter earnings from names like Arrhythmia Research Technology ( HRT). The Fitchburg, Mass., medical-software company more than halved its per-share income from last year to 9 cents, spurring a 37.3% slide to $12.11. Goldfield ( GV), a construction company from Melbourne, Fla., slid 11.8% to $1.05 after swinging to a penny-a-share loss from a 4-cent-a-share profit a year ago. HandHeld Entertainment ( ZVUE), the San Francisco-based maker of Zvue handheld media players, reported one-third lower revenue from last year at $584,000 even while cutting its first-quarter losses in half. Shares receded 10.8% to $1.90. Also sliding on poor financials was nightclub operator VCG Holding ( PTT), which was trading down 11.9% to $7.20 after revenue fell just short of the sole analyst's estimate. JED Oil ( JDO) posted a 23-cent-per-share loss vs. break-even last year, and printer-equipment maker Media Sciences International ( MSII) slid to break-even earnings from 4 cents a share a year ago. JED dropped 19.3% to $1.42; Media Sciences fell 9.9% to $5.75. Among small-cap stocks on the upswing, however, was East Penn Financial ( EPEN). The Emmaus, Pa., bank soared 66.3% to $13.45 after Harleysville National ( HNBC) agreed to buy it for about $14.50 a share, or $92.7 million, in cash and stock. The deal will probably close in the fall. Harleysville shares were recently unchanged.