Left ventricular filling and early diastolic function at rest and during angina in patients with coronary artery disease.

Abstract

Left ventricular diastolic function was studied in 11 patients with coronary artery disease. Single plane ventriculography (30 degrees right anterior oblique projection) was performed at rest and during an episode of angina immediately after a period of rapid atrial pacing. Left ventricular pressure was recorded simultaneously by a micromanometer tipped catheter. The ventriculograms were digitised frame by frame to derive continuous plots of left ventricular shape, volume, and rate of change of volume. The time constant (tau) of the fall in left ventricular pressure was determined from the exponential portion of pressure decay during isovolumic relaxation. Ventricular pressure-volume loops were constructed to study the left ventricular diastolic pressure-volume relation. The time of minimum left ventricular pressure was used to divide diastole into an early phase and a late phase. Angina was associated with an increase in end systolic volume and a fall in ejection fraction with no significant change in end diastolic volume. Peak left ventricular pressure was unchanged but left ventricular minimum and end diastolic pressures were both increased and the diastolic pressure-volume relation was moved upwards. The time constant of left ventricular pressure fall was prolonged. At rest more than 50% of the stroke volume entered the left ventricle during the period of early diastole. This proportion was significantly reduced during angina and as a consequence a significantly greater proportion of the stroke volume entered the ventricle during late diastole. Despite this, and although the left ventricular diastolic pressure-volume relation was moved upwards with angina, the mean slope of the relation during late diastole--that is, chamber stiffness--was not significantly altered. The upward shift of the left ventricular diastolic pressure-volume relation seen during angina is thus already apparent in early diastole, and its extent does not change during the later phase of diastole, which alone shows the property of passive stiffness. A primary increase in the passive stiffness of the ventricle cannot therefore be the cause of the upward shift of the diastolic pressure-volume relation, and events occurring in early diastole have to be looked to for an explanation. The study findings show that left ventricular function in early diastole is profoundly disturbed during angina pectoris and it is suggested that loss of elastic recoil and dissipation of this restoring force by asynchronous onset of relaxation and abnormal changes in shape are important factors contributing to this disturbance of function.

Left ventricular geometry and function are related to electrocardiographic characteristics and diagnoses

“…The most commonly used index of left ventricular diastolic function, the E/A ratio, was not altered in the present sample even in subjects with Q‐waves, probably due to coronary artery disease, in whom left ventricular diastolic dysfunction has repeatedly been shown in middle‐aged subjects (Dawson & Gibson, 1989; Carroll & Carroll, 1991). The possible reason for this is that left ventricular diastolic function and thus the E/A ratio declines with age also in healthy subjects (Appleton & Hatle, 1992), and that the effect of ageing in itself overrides the effects of the different pathological conditions in the present sample aged 70 years.…”

Echocardiographic diagnosis of left ventricular diastolic dysfunction: Impact of coronary artery disease

“…Doppler‐derived IVRT has been shown to be increased in hypertension and CAD, both of which are highly associated with LVDD 27‐29 . Impairment of early LV relaxation in CAD and LVDD was well established in clinical studies that used cardiac catheterization to assess IVRT or the time constant of the LV pressure exponential decay from intracardiac pressure recordings 30‐33 . In our study, IVRT ≥100 ms was very sensitive and specific in discriminating CAD and non‐CAD patients with diastolic abnormalities from non‐CAD patients (Table ).…”

Colour M-mode superiority in evaluation of improvement in myocardial performance indices following successful percutaneous coronary intervention (PCI)

“…It has been shown that early LV diastolic function becomes severely impaired during ischaemia 18. The early ventricular relaxation is a highly energy-dependent process 19.…”