Left Ventricular Wall Motion Assessed by Using Fixed External Reference Systems

Abstract

Of two methods utilized to assess ventricular wall motion, one (method A) assumes the left ventricular wall moves symmetrically during contraction toward the approximate geometric center of the left ventricle. The other (method B) assumes the left ventricular wall moves symmetrically toward the base of the heart. Clearly, both methods cannot be correct in all patients. We are presenting a method (R) which utilizes two external markers and the diaphragm as an internal marker to evaluate left ventricular contraction pattern. Of 44 patients studied, the diaphragm moved in four and ventricular wall motion could not be assessed. Fifteen patients had valvular heart disease; six were normal. Findings in method R corresponded to those determined by method B in five of eight patients (63%) with left ventricular hypertrophy and by method A in eight of 13 patients (62%) without left ventricular hypertrophy. This difference was significant ( P < 0.05). The remaining 19 patients had coronary artery disease; twelve of them had a previous myocardial infarction. In the latter, method R detected an area of asynergy (akinesis or dyskinesis) at ventriculography in ten of 12 patients (84%). The area of asynergy corresponded to the site of infarction determined by electrocardiogram in all patients. Methods A and B detected asynergy in only five of 12 patients (42%) and six of 12 patients (50%), respectively. Using two fixed external reference points and the diaphragm as an internal marker, a better evaluation of left ventricular wall motion can be obtained.