The Apexcardiogram in Myocardial Asynergy

Abstract

SUMMARYThe apexcardiogram was analyzed in 41 patients with an altered pattern of left ventricular contraction. Four types were distinguished: type I, an early sustained systolic bulge which occurred in 12 patients, all of whom had large aneurysms and large enddiastolic volumes; type II, a bulge confined to midsystole which occurred in 13 patients, 11 of whom had some form of ventricular asynergy; type III, a late or end-systolic bulge which occurred in 12 patients, seven of whom had ventricular asynergy; type IV, a prominent spike during diastolic filling which occurred in four patients who had large zones of ventricular asynergy. Additional Indexing Words:Aneurysm Abnormal myocardial contraction THE NORMAL apexcardiogram and its temporal relationship to electrical, acoustical, and mechanical cardiac events has been the subject of previous communications from various laboratories,1 2 including our own.3 The normal pattern is uniform, reproducible, and clearly correlated with known hemodynamic events.Lack of general agreement about the genesis of the apexcardiogram and technical difficulties in recording it have discouraged a more general use. The low frequency vibrations, which result from relative movement in the chest wall beneath the cup applicator, are thought to result from actual movement of the heart and great vessels, from changes in volume and velocity of movement of the heart, and from changes in the consistency and curvature of the heart wall.4' 5 Particular difficulty arises in attempting to evaluate systolic events from the apexcardiogram.

Microgel‐Based Devices as Wearable Capacitive Electronic Skins for Monitoring Cardiovascular Risks

“…Figure b,c shows the ACG of a 25 year old male volunteer, with an aneurysm, tested using the etalon. The etalon exhibits similar data to the ACG of patients with aneurysms reported by Gorlin and co‐workers and Jeong and co‐workers . The normal ACG of a healthy volunteer at the same age was obtained using the same sensor, as shown in Figure d.…”

“…An apexcardiogram (ACG) was obtained by attaching the etalon on the chest of volunteers, as shown in Figure a. The ACG is strongly associated with the hemodynamic state of the heart assisting in diagnosing atrial fibrillation, valve diseases, anemia, and myocardial infarction that are not easy to be diagnosed by electrocardiogram (ECG) . The ACG can be used with blood pressure and ECG data to generate a comprehensive evaluation of cardiovascular functions.…”

“…The normal ACG of a healthy volunteer at the same age was obtained using the same sensor, as shown in Figure d. The ACG has been divided into five segments by Gorlin and co‐workers and Jeong and co‐workers . The biggest peak (A–E) is the systolic wave that is caused by the isovolumetric contraction of ventricles.…”

Stretchable E‐Skin Apexcardiogram Sensor

“…[13] In the 1960s and 1970s, researchers reported that coronary artery disease (a group of heart diseases including angina pectoris, myocardial infarction, and sudden coronary death) abnormally increases the magnitude and duration of the "A" wave and creates a paradoxical bulge in the ESS. [11,13] Because such diseases can cause acute heart attack or myocardial infarction, they must be continuously monitored during ev eryday activities.…”

“…These diseases are not easily detected by ECG. [11][12][13] However, since the 1970s, the ACG has lost popularity because it is inconvenient to operate and requires large space in a sound-proof room. Small-size, inexpensive ACG sensors are expected to facilitate pragmatic, continuous hemodynamic monitoring in cardiac Adv.…”