Open AccessSequential Alterations in Myocardial Lactate Metabolism, S‐T Segments, and Left Ventricular Function During Angina Induced by Atrial Pacing
Author(s) -
PARKER JOHN O.,
CHIONG MIGUEL A.,
WEST ROXFOY O.,
CASE ROBERT B.
Publication year - 1997
Publication title -
annals of noninvasive electrocardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.494
H-Index - 48
eISSN - 1542-474X
pISSN - 1082-720X
DOI - 10.1111/j.1542-474x.1997.tb00206.x
Subject(s) - medicine , cardiology , angina , coronary artery disease , hemodynamics , electrocardiography , myocardial infarction
SUMMARY Myocardial lactate metabolism was monitored before, during, and after a period of atrial pacing with a continuous automated sampling technic. The electrocardiogram was recorded, and left ventricular function was evaluated by relating left ventricular end‐diastolic pressure to left ventricular stroke work. Seventeen of 21 patients with coronary artery disease experienced angina during pacing, and 13 of these showed lactate production by the myocardium during angina. The abnormalities in lactate metabolism developed early in the pacing period, along with S‐T segment depression and impairment of left ventricular function, all of which usually occurred before the onset of pain. In the patients with angina, the mean lactate extraction was 14.1% during the control period and —15.1% during the pacing period. Abnormalities in myocardial lactate metabolism have been demonstrated with greater regularity during pacing‐induced angina than during angina precipitated by exercise or isoproterenol. This investigation has demonstrated the sequences of changes in lactate metabolism during and after a period of angina and their relation to electrocardiographic and hemodynamic events.