RT Journal Article
SR Electronic
T1 Effect of postextrasystolic potentiation on amplitude and timing of regional left ventricular wall motion in ischaemic heart disease.
JF British Heart Journal
JO Heart
FD BMJ Publishing Group Ltd and British Cardiovascular Society
SP 466
OP 476
DO 10.1136/hrt.49.5.466
VO 49
IS 5
A1 D G Gibson
A1 E Fleck
A1 W Rudolph
YR 1983
UL http://heart.bmj.com/content/49/5/466.abstract
AB In order to investigate the effects of postextrasystolic potentiation on left ventricular wall motion, the left ventriculograms of 30 patients were digitised frame by frame and regional movement demonstrated by contour displays. Postextrasystolic potentiation caused significant increases in end-diastolic volume, ejection fraction, and peak ejection and filling rates. The amplitude of normally moving segments increased by 5.7 +/- 2.3 mm, regardless of initial amplitude. Hypokinetic segments moved normally if the initial amplitude was greater than 5 mm, and there was a reduced or absent response if 4 mm or less. Four specific abnormalities of timing of motion were studied during isovolumic contraction, early ejection, and isovolumic relaxation. Their timing and extent were all unaffected in postextrasystolic beats. These results thus give no evidence for the entity "reversible asynergy". Rather, they suggest that the response of local wall motion to postextrasystolic potentiation depends only on basal amplitude and increased volume change in postextrasystolic beats.