[Predictive factors of abnormal dynamic intraventricular gradient after valve replacement in severe aortic stenosis]. / Aparición de gradiente dinámico intraventricular después de la sustitución valvular aórtica en pacientes con estenosis aórtica severa.

ABSTRACT

INTRODUCTION: Dynamic intraventricular gradients (DIG) after valve replacement in severe aortic stenosis have been reported, although the incidence of DIG and clinical signs are still poorly understood.Aim. To evaluate the incidence of DIG)and determine risk factors and associated morbimortality. PATIENTS AND METHOD: One hundred nine consecutive patients with severe aortic valve stenosis undergoing valve replacement were studied prospectively by echocardiography to detect the postoperative appearance of DIG, defined as a maximum flow velocity >/= 2.5 m/s. RESULTS: Sixteen patients (14.9%) developed postoperative DIG. Significant differences between the patients with or without DIG were found for ventricular diameter (left end-diastolic ventricular diameter (LEDVD) 43.2 vs. 47.7 mm, respectively, p < 0.001; left end-systolic ventricular diameter (LESVD) 21 vs. 29 mm, p < 0.001); left ventricular mass index (165 vs. 193 g/m(2), p < 0.05); mean aortic valve gradient (68 vs. 59 mmHg, p < 0.01),; ejection fraction (73 vs. 61%, p < 0.001). No significant differences were found with respect to ventricular wall thicknesses (septal 16.3 vs. 15.7; posterior 14.37 vs. 14.62), the presence of aortic insufficiency, or other postoperative factors (anemia, inotropic agents, etc.). CONCLUSIONS: DIG after aortic valve replacement to treat severe stenosis is not unusual (15%). DIG is usually found at a midventricular location, close to the septum. In patients with postoperative DIG the most common associated factors were small LEDVD, high ejection fractions and ratios of intraventricular septal to posterior wall ratios, high valve gradients and small left ventricular masses. Preoperative echocardiography can identify patients with a higher risk of developing DIG after aortic valve replacement.