The apexcardiogram in ischemic heart disease.

The apexcardiogram (acg), when recorded serially in patients with acute myocardial infarction (ami), preinfarction angina (pia) and stable ischemic heart disease (ihd), appeared to reflect the abnormal patterns of contraction of the left ventricle in these conditions. Thus, paradoxical bulging (dyskinesis) of the systolic wave or increased "a" wave amplitude with gradual recovery over several weeks was found in all 60 patients with documented ami and in 18 of 20 patients with pia. Electrocardiogram changes were noted, however, in only eight of the pia patients. Changes in the acg frequently antedated ischemia in the ecg. Paradoxical bulging of the systolic wave of the acg was additionally noted in patients during the pain of angina pectoris but this promptly disappeared after the administration of nitroglycerine. Patients with classic angina often had normal resting ecg's but abnormal resting acg's. In contrast to the relatively transient abnormalities noted above, the acg remained unchanged in most patients with stable ihd during follow-up of three months to two years. Patients undergoing coronary bypass operations, however, showed immediate improvement in the acg in the postoperative period. These results suggest the acg reflects the contractile pattern of the left ventricle, and may be an indirectly recorded ventriculogram. Its enhanced sensitivity and the earlier development of changes in comparison to the ecg make this a valuable tool in the study of patients with heart disease.