[Prognostic indices of the normalization of left ventricular function in chronic aortic insufficiency following valve replacement]. / Indices prédictifs de normalisation de la fonction ventriculaire gauche dans les insuffisances aortiques chroniques après remplacement valvulaire.

ABSTRACT

The aim of this study of 31 patients was to identify M mode echocardiographic parameters predictive of normalisation of left ventricular function after valvular replacement for chronic aortic incompetence in order to determine the optimal time for surgery. Only patients with chronic, pure aortic incompetence (ventriculo-aortic pressure gradient less than or equal to 30 mmHG) were considered. At the time of investigation 4 patients were in functional Class I, 6 in Class II, 10 in Class III and 11 in Class IV (NYHA). M mode echocardiography was performed on an Echovideorex or an Irex System II echocardiograph. The following measurements were made and corrected for body surface area according to the recommendations of the American Society of Echocardiography; end systolic and end diastolic dimensions (mm), fractional shortening (%), end systolic and end diastolic wall thickness (mm), diastolic radius to wall thickness ratio, short axis myocardial surface area (cme), wall stress, end systolic stress (mmHg). The study comprised pre and postoperative studies with an interval of 22.7 +/- 12.5 months (range 5 to 46 months); the data obtained was compared with a control group of 10 normal subjects. The results showed that preoperative fractional shortening less than 28% was associated with an increased risk of persistent postoperative left ventricular dysfunction.