RÉSUMÉ
Background:Obstructive sleep apnea syndrome (OSA) is a common but often under diagnosed condition.According to literature,OSA prevalence in atrialfibrillation (AF) patients varies from 21 to 85%. OSA is increasingly recognized as a risk factor for biventricular dysfunction. The present study aimed to compare left and right ventricular functions, assessed by conventional echocardiographic parametersand speckle tracking imaging, in non-valvular atrial fibrillation (NVAF) patients with and without severe OSA.Methods: Across-sectional analytic study was conducted. Forty successive patients with NVAF were included. All of them had a clinical screeningfor symptoms suggestive of OSA and underwent polysomnographic study. Patients were divided into two groups (group 1: without severe OSA with an apnea-hypopnea index (AHI) < 30 events per hour (e/h), and group 2: having severe OSA with an AHI ≥ 30 e/h). Echocardiography was performed in all patients. Left and right ventricular function parameters were measured including global longitudinal strain (GLS) and myocardial performance index (MPI).Results: OSA was diagnosed in 90% of NVAF patients. The average AHI was 22.1 ± 13 e/h.Eleven patients (27.5%) had mild OSA, 9 patients (22.5%) had moderate OSA, and 16 patients (40%) had severe OSA.General clinical characteristics were comparable between groups.A statistically significant association was demonstrated between severe OSA and impairment of left ventricular GLS (-17.3 ± 4.5 vs. -14.9 ± 3%, in group 1 and 2 respectively, p = 0.02) and left ventricular MPI (0.37 ± 0.09 vs. 0.49 ± 0.13, in group 1 and 2 respectively, p = 0.01).Right ventricular lateral wall strain was non significantly lower in group 1 compared to group 2 (-22.5 ± 8.4 vs. -18.4 ± 5.8%, in group 1 and 2 respectively, p = 0.15).On multivariate logistic regression analysis, left ventricular GLS impairment (> -18%) and MPI > 0.37 were independent predictors of severe OSA.Conclusion: Severe OSA was diagnosed in 40% of NVAF patients. Impairment of left ventricular GLS and left MPI were statistically associated with severe OSA
RÉSUMÉ
Background: Left ventricular outflow tract (LVOT) obstruction is a serious complication that can occur after various mitral-valves, surgical or percutaneous, interventions. It was rarely described in mechanical mitral valve replacements. Aim: to describe a rare case of late LVOT obstruction after a mitral valve replacement by a low-profile mechanical prosthesis. Case Presentation: A 48-year woman, with a history of rheumatic mitral valve disease and mechanical mitral replacement by a hemi-disc valve 18 years ago, presented for a recent dyspnea. Echocardiography showed a narrowing of the LVOT, with anterior position of the mitral prosthesis, aorto-mitral annular angulation, septal thickening and remnant native sub-valvular tissue attached to the septum in the LVOT region. This resulted in LVOT obstruction with a peak gradient of 75 mmHg. The heart team opted for a redo surgery, but the surgical decision was refused by the patient. Discussion: This is a rare case of late LVOT obstruction after mitral valve replacement by mechanical low-profile prosthesis. Preserved native mitral valve tissue, which is the main described cause of LVOT obstruction after mechanical mitral valve replacements was not the unique cause of obstruction in this patient who had also a septal thickening and anterior prosthetic position. Aorto-mitral annular angulation that was identified as a risk factor of LVOT obstruction after trans-catheter mitral valve replacements, should be, probably, also took into account and assessed pre-operatively in patients undergoing surgical mitral replacements. Conclusion: LVOT obstruction can occur after mechanical mitral replacements event with low profile prosthesis. In patients with identified risk factors of LVOT obstruction, preservation mitral anterior leaflet should be avoided, and preservation of other native mitral tissue should be discussed.