The apex cardiogram and its relationship to haemodynamic events within the left heart.

Abstract

Low-frequency pulsations (20 cycles a second or less) appearing on the surface of the chest over the region of the cardiac apex have been studied sporadically for many years, but recently they have attracted considerable attention These pulsations possess considerable amplitude in comparison with the higher frequency sound vibrations and generally can be recorded easily. Most observers would agree that motion of the left ventricle causes the major, if not the only, low-frequency deflections on the chest wall in this region; however, interpretation of the recordings has been hampered by lack of precise knowledge about how these vibrations correlate with hmmodynamic events within the left side of the heart.