TY - JOUR
T1 - QRS morphology-dependent pharmacodynamics in multiform ventricular ectopic activity
AU - Kessler, Kenneth M.
AU - McAuliffe, Daneil
AU - Kozlovskis, Patricia
AU - Trohman, Richard G.
AU - Zaman, Liaqat
AU - Castellanos, Agustin
AU - Sequeira, Rafael F.
AU - Myerburg, Robert J.
PY - 1988/3/1
Y1 - 1988/3/1
N2 - The effect of an infusion of intravenous procainamide on the frequency of ventricular premature complexes (VCPs) of differing QRS morphologies was studied in 20 patients with multiform ectopic activity. In 17 of 20 patients, there was differential suppression of single VPCs with different QRS morphologies. VPCs of the most frequent QRS morphology and the second most frequent QRS morphology were compared with respect to the procainamide level at the escape of VPCs from 85% suppression and the duration of suppression measured from the onset of the procainamide infusion. In 8 patients, VPCs of the most frequent QRS morphology remained suppressed at lower procainamide concentrations and for longer times than did VPCs of the second most frequent QRS morphology (escape procainamide concentration = 2.8 ± 1.7 versus 5.4 ± 2.3 μug/ml, p < 0.025; time to escape 244 ± 138 versus 98 ± 114 min; p < 0.05). 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 μg/ml, p < 0.025; time to escape 317 ± 114 versus 63 ± 80 min; p < 0.001). Thus, in individual patients there are specific patterns of suppression of VPCs of different QRS morphologies which are independent of the frequency of each morphology. There is apparently a differential pharmacologiceffect of procainamide on the foci or pathways responsible for the different QRS morphologies of multiform VPCs.
AB - The effect of an infusion of intravenous procainamide on the frequency of ventricular premature complexes (VCPs) of differing QRS morphologies was studied in 20 patients with multiform ectopic activity. In 17 of 20 patients, there was differential suppression of single VPCs with different QRS morphologies. VPCs of the most frequent QRS morphology and the second most frequent QRS morphology were compared with respect to the procainamide level at the escape of VPCs from 85% suppression and the duration of suppression measured from the onset of the procainamide infusion. In 8 patients, VPCs of the most frequent QRS morphology remained suppressed at lower procainamide concentrations and for longer times than did VPCs of the second most frequent QRS morphology (escape procainamide concentration = 2.8 ± 1.7 versus 5.4 ± 2.3 μug/ml, p < 0.025; time to escape 244 ± 138 versus 98 ± 114 min; p < 0.05). 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 μg/ml, p < 0.025; time to escape 317 ± 114 versus 63 ± 80 min; p < 0.001). Thus, in individual patients there are specific patterns of suppression of VPCs of different QRS morphologies which are independent of the frequency of each morphology. There is apparently a differential pharmacologiceffect of procainamide on the foci or pathways responsible for the different QRS morphologies of multiform VPCs.
UR - http://www.scopus.com/inward/record.url?scp=0024159642&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024159642&partnerID=8YFLogxK
U2 - 10.1016/0002-9149(88)90765-5
DO - 10.1016/0002-9149(88)90765-5
M3 - Article
C2 - 3344680
AN - SCOPUS:0024159642
VL - 61
SP - 563
EP - 569
JO - American Journal of Cardiology
JF - American Journal of Cardiology
SN - 0002-9149
IS - 8
ER -