The relation between left ventricular asynchrony, relaxation, outward wall motion and filling characteristics during control period and pacing-induced myocardial ischaemia in coronary artery disease.
To assess the relation between left ventricular asynchrony, relaxation, outward wall motion and filling in patients with coronary artery disease and normal systolic function, pressure measurements and left ventricular angiography were performed at rest and after pacing. Asynchrony and outward wall motion were quantified by segmental area-time curves. At rest, there were no differences in asynchrony and time constant between 10 patients with coronary artery disease and 10 normal subjects, while the early-filling rate was less in patients with coronary artery disease than in normal subjects. Six coronary artery disease patients with isolated left anterior descending disease displayed anterior outward wall motion which was less than that of normal subjects. In 10 coronary artery disease patients with pacing-induced angina, asynchrony increased, time constant prolonged and the early-filling rate decreased. In 6 coronary artery disease patients with isolated left anterior descending disease, anterior outward wall motion decreased after pacing. Thus, impaired early diastolic filling at rest in patients with coronary artery disease and normal systolic function may result not from asynchrony nor impaired relaxation, but from reduced regional outward wall motion of the affected area supplied by diseased coronary artery during early diastole. However, during ischaemia temporal asynchrony and impaired relaxation possibly add to left ventricular filling impairment in patients with coronary artery disease.
D000328:Adult; D000787:Angina Pectoris / Q000209:etiology; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects; D003327:Coronary Disease / Q000503:physiopathology*; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011312:Pressure; D013997:Time Factors