The Use of Apexcardiography in the Assessment of Left Ventricular Diastolic Pressure

Abstract

A total of 58 observations of simultaneous left ventricular pressure and apex-cardiograms (ACG) was made on 18 patients. An a wave percentage amplitude (aWPA) of greater than 15% of the total deflection of the ACG indicated an increase in left ventricular end-diastolic pressure (LVEDP). In 12 observations on six patients, an aWPA of less than 15% was associated with a high LVEDP. Patients with high LVEDP and aWPA of less than 15% had a high early left ventricular diastolic pressure with further rise in pressure prior to atrial contraction. These patients had small LV a waves ("atrial kick"). The aWPA of the ACG correlated better with the magnitude of the LV a wave than the absolute level of LVEDP in all patients. Correlation was good between changes in aWPA and changes in LVEDP in individual patients; but the ACG as an indirect means of evaluating left ventricular function is limited by the fact that elevations in LVEDP can exist in the presence of a normal aWPA. The ACG is a complex tracing reflecting not only intracardiac pressures, but changes in left ventricular volume, compliance, position, and perhaps left atrial function as well.

Diastolic flow velocity pattern of the left anterior descending coronary artery in hypertrophied heart, with special reference to the difference between hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy

“…The A wave ratio of ACG has been known as an index indicating elevated end-diastolic stiffness of the LV on the basis of its excellent correlation with LV end-diastolic pressure or A wave amplitude of the LV pressure curve [19][20][21]. In this study, the A wave ratio of ACG was significantly greater in the group with LDS formation than in the group without.…”

“…First, since the intracardiac pressure measurements were not performed in all patients, we could not evaluate the correlation between intracardiac pressure and the LAD flow velocity pattern. It has been known that the A wave ratio of ACG correlates well with the LV end-diastolic pressure or A wave amplitude of the LV pressure curve [19][20][21]. Therefore, we used the A wave of ACG as an estimate for LV end-diastolic pressure.…”

Value of systolic and diastolic time intervals. Studies in normotensive and hypertensive 50-year-old men and in patients after myocardial infarction.

“…An a/H ratio above 15 per cent was considered abnormal (Voigt and Friesinger, 1970;Wikstrand et al, 1976). Limits for abnormal time intervals were arbitrarily set at the second highest or lowest value in the reference group, depending on whether a high or low value of the variable concerned was of pathological significance.…”

Clinical Value of Types of Exercise-Induced Diastolic Abnormalities in Patients with Myocardial Disease

“…We have first described the temporal coincidence of the onsets of systolic upstrokes and, in part, also of the diastolic nadirs of apex and left ventricu lar pressure tracings using simultaneous high-fidelity trac ings during diagnostic heart catheterization [17,18]. Fur ther, it has been found by many authors that relative A wave height parameters correlate significantly not only with left ventricular end-diastolic pressure [34,[36][37][38] but also with internally derived indices of end-diastolic pressure-volume relation [20,39]. According to all these findings the apex tracing represents the only hitherto available noninvasive method which reflects left ventricu lar pressure changes.…”