ANGIOGRAPHIE VENTRICULAIRE GAUCHE QUANTITATIVE. IMPROTANCE, PRONOSTIC A COURT ET LONG TERME DANS LE REMPLACEMENT VALVULAIRE MITRAL ISOLE

A retrospective study of 95 patients undergoing isolated mitral-valve replacement was carried out. The mean age was 49 years; the average post-operative follow-up was 32 months. All patients had undergone quantitative left-ventricular angiography on average 2 months before surgery. The parameters studied were left-ventricular end diastolic volume index (EDV), ejection fraction (EF), myocardial mass (related to EDV and expressed as the hypertrophy coefficient (HC), and the coefficient of ventricular excentricity (E) which analysed the morphology of the LV. The mitral lesions were classified as: mitral stenosis (20 cases), Group I; mixed mitral disease (53 cases), Group II; pure mitral insufficiency (18 cases), Group III, and other lesions (4 cases), Group IV. The operative mortality rate was 7,3% and was unrelated to the preoperative state (5/7 deaths due to thrombosis or infection of the prosthesis). Fifteen patients developed postoperative low-output syndromes for no obvious reasons. There was no overall predictive factor of this complication, but in Group II in which 11 low-output states occurred, there was a significant relationship with a reduced EF (47% when EF ≤ 50% compared to 9% when EF ≥ 50%, P < 0.01). The five-year survival-rate was 68% overrall, with no significant difference between the groups. The long-term mortality was greater when the EF was low (2% deaths when EF ≥ 50% compared to 17,1% when EF ≤ 50%, p < 0,02). Analysis showed that Groups II, III and IV (patients with mitral insufficiency) were responsible for this difference. Thirteen poor results were related to myocardial dysfunction (verified by postoperative angiography in 8 cases). The preoperative EF was lower in these cases compared to the rest of the patients (EF = 46±8% compared to 54±9%, p < 0,01). The majority of myocardial dysfunctions were observed in Group II. These cases were characterised by lower preoperative EF, greater LV dilatation and a more spherical LV morphology than patients who had good results. Thre preoperative EF appeared to be the most useful angiographic parameter for assessing the immediate and long-term prognosis. This study should help pose the operative indications at an earlier stage in order to improve the immediate and long-term results of isolated mitral-valve replacement.