The kinetocardiogram in patients with ischemic heart disease

Abstract

The conclusions derived from the foregoing consideration of precordial movements in patients with ischemic heart disease may be summarized as follows. The subjective approach, i.e., the history, remains the single most useful guide to the diagnosis of angina pectoris. Such objective methods as the electrocardiogram and the measurement of serum enzymes are ordinarily the most valuable procedures in the recognition of myocardial infarction. In a patient suspected of having myocardial infarction or in a person observed during an anginal attack, an atypical history may at times be clarified by feeling an abnormal and sustained outward systolic motion of the precordium. This is most likely to be felt in the left precordial area (involvement of the interventricular septum), in the region of the apex (apical ischemia), and, occasionally, in the left fourth interspace in the midclavicular or left anterior axillary lines (lateral wall of the left ventricle). These findings become much more significant when the patient has no evidence of a lesion capable of causing either right or left ventricular hypertrophy. The kinetocardiogram often indicates inefficiency of left ventricular function in patients with ischemic heart disease. There may be incoordinate contraction, a portion of the energy produced by the normal muscle being expended not in expelling blood but in stretching the ischemic tissue. The kinetocardiogram is essentially a method of making physical examination more delicate and more accurate. It not only records outward impulses which, when marked, can be felt, but also inward motions which cannot be felt at all and usually not seen. Even with outward motions, the kinetocardiogram has the advantage of being much more sensitive and, when coupled with the electrocardiogram and the carotid pulse rate, of yielding—more accurately than the hand—information concerning the timing of paradoxic movements. In that large percentage of patients who have clinical and/or electrocardiographic evidence of ischemic heart disease, the kinetocardiogram provides nothing more than confirmation. Sometimes it is entirely normal when the other methods clearly indicate that coronary disease is present. Occasionally, the kinetocardiogram yields decisive information when that obtained from the other procedures is inconclusive. For the greatest precision in diagnosis, all of these methods may need to be employed. There is no royal road to the diagnosis of ischemic heart disease.