in 9 other patients , vpcs of the second most frequent qrs morphology remained suppressed at lower procainamide concentrations and for longer times than did vpcs of the most frequent qrs morphology ( escape procainamide concentration 2.9 +/- 1.4 versus 8.3 +/- 6.3 micrograms/ml , p less than 0.025 ; time to escape 317 +/- 114 versus 63 +/- 80 min ; p less than 0.001 ) .
C0151636
vpcs
C0033216
procainamide