Relationship between ventricular gradient and the impairment of wall motion of the left ventricle in coronary artery disease.

Abstract

Fifty patients with or without coronary artery disease were studied. Twelve of them showed no coronary artery obstruction, while 38 demonstrated obstruction of the left anterior descending artery (LAD). Of the latter 38, 16 had obstruction at LAD alone, 6 at LAD and right coronary artery (RCA), 8 at LAD and left circumflex artery (LCx) and 8 at LAD, RCA and LCx. Vectorcardiography, selective coronary cineangiography and left ventricular cineangiography were undertaken in all subjects. The vectorcardiogram (VCG) was recorded on a magnetic tape and QRS area vector (Aqrs), T area vector (At) and ventricular gradient (G) were calculated by micro-computer. From left ventriculogram (LVG) "score" was computed to express the grade of impairment of the wall motion. Correlations between various vector-cardiographic parameters and this score were examined. The score correlated significantly (p less than 0.001) with azimuth of Aqrs (r = -0.545), azimuth of At (r = 0.661), magnitude of G (r = -0.705), azimuth of G (r = 0.533), G/Aqrs (r = -0.645), spatial angles between Aqrs and At (r = 0.591) and between max R and max T (r = 0.595) and X component of G (r = -0.758). These results suggested the usefulness of ventricular gradient to grasp the grade of coronary artery disease.