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Management of asymptomatic patients with severe aortic valve stenosis (AVS) remains a source of debate. Exercise testing is no longer contraindicated and needs now to be considered when evaluating asymptomatic patients with AVS. Several studies have clearly demonstrated that exercise-elicited symptoms during conventional upright exercise portends clinical events. Semi-supine exercise with continuous Doppler echocardiography monitoring elicits cardiovascular abnormalities that are not detected at rest. Abnormal left ventricular response to exercise and/or major increase in mean transvalvular gradient add to the prognostic value of elicited symptoms in asymptomatic patients with severe AVS. However, preliminary experience needs to be confirmed to warrant routine use of exercise Doppler echocardiography in the evaluation of patients with asymptomatic AVS.

Background: Left ventricular (LV) longitudinal deformation is a good marker of intrinsic myocardial dysfunction in pressure overload cardiomyopathies. Aim: To assess the effect of valvuloarterial haemodynamic load on LV longitudinal deformation in patients with aortic valve stenosis (AVS) and preserved LV ejection fraction (LVEF). Methods: Global LV longitudinal strain (GLS) was measured using speckle tracking imaging in a series of 82 consecutive patients with AVS (mean age 75 ± 10 years; 50% men). The global (valvular + arterial) haemodynamic load imposed on the LV was estimated by the valvuloarterial impedance (Zva), and was calculated using either arm-cuff systolic peripheral blood pressure or systolic central aortic blood pressure estimated by SphygmoCor®. Results: Among this series of 82 patients with preserved LVEF, 79% had reduced LV GLS (< -18%). LV GLS correlated weakly with AVS severity, systemic vascular resistance and systemic arterial compliance. However, there was a good inverse correlation between increase in Zva and impairment of LV GLS (r = 0.41 p < 0.0001). On multivariable analysis, impaired GLS was associated with increased Zva (p < 0.0001), increased E/Ea ratio (p = 0.001) and increased LV end-diastolic volume index (p = 0.021), while indices of valvular load were not. Utilization of estimated central aortic blood pressure in place of brachial pressure did not improve the performance of Zva to predict GLS. Conclusion: The magnitude of the global haemodynamic load as reflected by Zva is a powerful determinant of altered LV longitudinal deformation in AVS patients with preserved LVEF. The calculation of Zva may be useful to identify the patients who are potentially at higher risk for the development of myocardial dysfunction. Use of estimated central aortic pressure in the calculation of Zva does not appear to provide any incremental predictive value over that calculated with the simple measurement of brachial pressure., Contexte: La déformation longitudinale du ventricule gauche (VG) est un bon marqueur de dysfonction myocardique intrinsèque dans les cardiomyopathies avec surcharge de pression. But: Évaluer l’effet de la charge hémodynamique valvulo-artérielle sur la déformation longitudinale du VG de patients porteurs d’une sténose valvulaire aortique et d’une fraction d’éjection préservée. Méthodes: La déformation globale longitudinale du VG a été mesurée à l’aide de l’imagerie speckle tracking dans une série de 82 patients consécutifs porteurs d’une sténose valvulaire aortique (âge moyen 75 ± 10 ans, 50 % d’hommes). La charge hémodynamique globale (valvulaire + artérielle) imposée au VG a été estimée par l’impédance valvulo-artérielle (Zva) et a été calculée en utilisant soit la pression périphérique systolique brachiale au brassard, soit la pression systolique centrale aortique estimée par le SphygmoCor®. Résultats: Parmi cette série de 82 patients avec une fraction d’éjection préservée, 79 % avaient une déformation globale longitudinale du VG réduite (< -18 %). La déformation globale longitudinale du VG été faiblement corrélée avec la sévérité de la sténose aortique, les résistances vasculaires systémiques et la compliance artérielle systémique. Toutefois, une bonne corrélation était observée entre l’augmentation du Zva et l’altération de la déformation globale longitudinale du VG (r = 0,41 p < 0,0001). En analyse multivariée, l’altération de la déformation longitudinale du VG était associée avec un Zva (p < 0,0001), un rapport E/Ea (p = 0,001) et un volume télédiastolique du VG indexé (p = 0,021) plus élevés. L’utilisation de l’estimation de la pression aortique centrale en remplacement de la pression brachiale n’améliorait pas la performance du Zva comme déterminant de la déformation longitudinale du VG. Conclusion: L’importance de la charge hémodynamique globale représentée par le Zva est un déterminant puissant de l’altération de la déformation longitudinale du VG des pati

BACKGROUND: Functional mitral regurgitation (FMR) may occur in patients with reduced or preserved left ventricular ejection fraction (LVEF) and has been associated with excess valvular tenting only in patients with reduced LVEF. This study aimed at identifying the predictors of FMR and to determine whether or not they are different in patients with reduced versus preserved LVEF. METHODS: 190 consecutive patients free of congenital or primary valvular disease had a comprehensive echocardiographic assessment of LV remodelling and function, diastolic function and FMR severity. RESULTS: 112 patients had depressed LVEF (<50%) and 78 had preserved LVEF. FMR was present in 30 patients with preserved LVEF and in 65 with reduced LVEF. Higher E/Ea, E/A and larger mitral tenting were independent predictors of FMR regardless of LVEF. The mitral tenting area was an independent predictor of FMR severity in patients with reduced or preserved LVEF (p = 0.04 and p = 0.0045) in addition to E/A (p = 0.0007), E/Ea (p = 0.004) in patients with reduced and preserved LVEF, respectively. Higher E/Ea was independently associated with larger mitral tenting in patients with reduced and preserved LVEF. Mitral tenting area was linearly related to E/Ea (r = 0.30, p<0.0001) and E/A (r = 0.43, p<0.0001) and LA enlargement (r = 0.54, p<0.0001) after having paired 96 patients with and without FMR on indices of LV remodelling. CONCLUSIONS: In both patients with preserved and reduced LVEF, mitral tenting that leads to FMR is mainly determined by both mitral tethering forces-that is, displacement of papillary muscles and by pushing forces-that is, increased left atrial pressure. This study underscores that LV preload is a key determinant of FMR.

Management of asymptomatic patients with severe aortic valve stenosis (AVS) remains a source of debate. Exercise testing is no longer contraindicated and needs now to be considered when evaluating asymptomatic patients with AVS. Several studies have clearly demonstrated that exercise-elicited symptoms during conventional upright exercise portends clinical events. Semi-supine exercise with continuous Doppler echocardiography monitoring elicits cardiovascular abnormalities that are not detected at rest. Abnormal left ventricular response to exercise and/or major increase in mean transvalvular gradient add to the prognostic value of elicited symptoms in asymptomatic patients with severe AVS. However, preliminary experience needs to be confirmed to warrant routine use of exercise Doppler echocardiography in the evaluation of patients with asymptomatic AVS.

Sanja Jelic1,  David J Lederer1, Tessa Adams1, Margherita Padeletti1, Paolo C Colombo2, Phillip Factor1, Thierry H Le Jemtel31Division of Pulmonary, Allergy, and Critical Care Medicine, 2Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, NY, USA; 3Division of Cardiology, Tulane University School of Medicine, New Orleans, LA, USAPurpose: To investigate the impact of obstructive sleep apnea (OSA) on endothelial repair capacity and apoptosis in the absence of potentially confounding factors including obesity. Patients and methods: Sixteen patients with a body mass index <30 and newly diagnosed OSA and 16 controls were studied. Circulating levels of endothelial progenitor cells, a marker of endothelial repair capacity, and endothelial microparticles, a marker of endothelial apoptosis, were quantified before and after four-week therapy with continuous positive airway pressure (CPAP). Endothelial cell apoptotic rate was also quantified in freshly harvested venous endothelial cells. Vascular reactivity was measured by flow-mediated dilation.Results: Before treatment, endothelial microparticle levels were greater and endothelial progenitor cell levels were lower in patients with OSA than in controls (P < 0.001 for both). Levels of endothelial microparticles and progenitors cells were inversely related (r = -0.67, P < 0.001). Endothelial progenitor cell levels increased after effective treatment (P = 0.036). Conclusions: In the absence of any co-morbid conditions including obesity, OSA alone impairs endothelial repair capacity and promotes endothelial apoptosis. These early endothelial alterations may underlie accelerated atherosclerosis and increased cardiovascular risk in OSA. Keywords: sleep apnea, endothelium, apoptosis, endothelial repair capacity

Besides its usefulness for the detection of exercise-induced ischemia, conventional exercise testing may help to predict the onset of clinical events and the need for surgery in asymptomatic patients with cardiac-valvular disease. Doppler echocardiography examination during exercise recently emerged as a new stress testing modality that may add useful information regarding dynamism of LV function, valve disease severity and pulmonary circulation. Few studies have demonstrated a correlation between the results of exercise Doppler echocardiography and clinical outcome. Preliminary experience needs to be confirmed to warrant routine use of Doppler echocardiography examination during exercise in the evaluation of patients with cardiac-valve disease. (C) 2008 Elsevier Masson SAS. All rights reserved.