Dynamic ventriculography in patients with ischaemic heart disease. II. Influence of postextrasystolic potentiation on left ventricular function.

The effect of postextrasystolic potentiation [PESP] on left ventricular [LV] function was assessed by means of left ventricular cineangiography in 26 patients with ischaemic heart disease. Ventricular extrasystoles were induced by a catheter inserted into the LV during injection of the contrast agent. The values of parameters of segmental and global function of LV, found in potentiated and nonpotentiated sinus contractions, were compared. Segmental disturbances present at rest in 13 patients improved or disappeared after extrasystole in 8 patients. Improvements in contraction also took place in segments with normal resting contraction. Global LV function improved significantly; an improvement was observed even without an increase in the LV end-diastolic volume in the postextrasystolic beat. The advantages and limitations of the method for preoperative estimation of the effect of intended myocardial revascularization on the LV function are discussed.