[Assessment of left ventricular function in patients with aortic regurgitation using dynamic investigation (author's...

To assess accurately left ventricular function (LVF) in patients with aortic regurgitation (AR pts), isometric exercise (IE) was used in association with postextrasystolic potentiation (PESP) during diagnostic heart catheterization including left cineventriculography in 16 pts with pure moderate or severe AR. The results were compared with those observed in 8 control pts (C pts). IE resulted in a significant increase in heart rate by 15 p. cent and in an increase in mean aortic pressure by 29 p. cent (p < 0.001). During IE, LV end diastolic pressure (EDP) remained unchanged in C pts and in 6 AR pts whereas this value was increased by 49 p. cent (p < 0.01) in 7 AR pts without a significant change in LV end diastolic volume. Ejection fraction (EF) was decreased in each AR pt (mean 14 p. cent; p < 0.001) and remained unchanged in C pts. A negative correlation was evidenced between the decrease in EF and the increase in LVEDP (r = 0.76). PESP resulted in a increase in EF in both C pts and AR pts (+ 25 and + 29 p. cent respectively; p < 0.001). PESP under IE resulted in a lower increase in EF than PESP under basal conditions (+ 19 and + 24 p. cent respectively) mainly due to the increase in after load provided by IE. Dynamic investigation of the LVF in AR pts is a physiological method of investigation easy to perform which may assess both LV contractile reserve and cardiac reserve. Such a method of investigation may help to select AR pts for surgery.