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The coexistence of aortic valve stenosis (AS) with hemodialysis arteriovenous (AV) fistula complicates the assessment of the severity of valvular disease. We describe the physiological changes in stenotic indices which occur following manual compression of the AV fistula. The manual compression of the AV fistula is capable of inducing significant alterations in transvalvular flow rates and valvulo-arterial impedance that translates into important changes in aortic valve hemodynamics and grading of stenosis severity.

BACKGROUND: Several studies suggest that BNP testing may help define the timing of aortic valve surgery in patients with aortic valve stenosis (AVS) prior onset of overt LV systolic dysfunction. The aim of this study was to identify clinical and echocardiographic correlates of plasma BNP levels in a large cohort of patients with AVS and preserved LV ejection fraction. METHOD AND RESULTS: One hundred thirty-five consecutive patients were prospectively included in the present study (Mean age 73 ± 13 years old, 66 (49%) male). Eighty-nine patients (66%) had severe AVS (aortic valve area <0.6 cm(2) /m(2) BSA). Plasma BNP levels, clinical and comprehensive Doppler echocardiography evaluation was performed in all patients. Independent clinical correlates of plasma BNP levels (R(2) = 0.19) were older age (P < 0.0001) and presence of AVS symptoms (P = 0.004). Independent echocardiographic correlates of plasma BNP levels (R(2) = 0.38) were E/Ea ratio (P = 0.01), LV mass index (P = 0.018), left atrial surface (P < 0.0001) and systolic pulmonary artery pressure (sPAP; P = 0.004). Overall, independent correlates of plasma BNP levels (R(2) = 0.47) were older age (P = 0.001), known coronary artery disease (P = 0.047), increased LV mass index (P = 0.001), left atrial enlargement (P = 0.002), and increased sPAP (P = 0.003). CONCLUSIONS: In patients with AVS and normal LV ejection fraction, plasma BNP predominantly reflects the clinical and echocardiographic consequences of afterload burden imposed on the left ventricle rather than the severity of valve stenosis, per se.

Aims : Abnormal exercise test defined as the occurrence of exercise limiting symptoms, fall in blood pressure below baseline, or complex ventricular arrhythmias is useful to predict clinical events in asymptomatic patients with aortic stenosis (AS). The purpose of this study was to determine whether exercise-stress echocardiography (ESE) adds any incremental prognostic value to resting echocardiography in patients with AS having a normal exercise response. Methods and results : One hundred and eighty-six asymptomatic patients with at least moderate AS and preserved LV ejection fraction (=50%) were assessed by Doppler-echocardiography at rest and during a maximum ramp semi-supine bicycle exercise test. Fifty-one (27%) patients had an abnormal exercise test and were excluded from the present analysis. Among the 135 patients with normal exercise test, 67 had an event (aortic valve replacement motivated by symptoms or cardiovascular death) at a mean follow-up of 20+14 months. The variables independently associated with events were: age =65 years [hazard ratio (HR) ¼ 1.96; 95% confidence interval (CI): 1.15–3.47; P ¼ 0.01], diabetes, (HR ¼ 3.20; 95% CI: 1.33–6.87; P ¼ 0.01), LV hypertrophy (HR ¼ 1.96; 95% CI: 1.17–3.27; P ¼ 0.01), resting mean gradient .35 mmHg (HR ¼ 3.60; 95% CI: 2.11–6.37; P , 0.0001), and exercise-induced increase in mean gradient .20 mmHg (HR ¼ 3.83; 95% CI: 2.16–6.67; P , 0.0001). Conclusion : The exercise-induced increase in transvalvular gradient may be helpful to improve risk stratification in asymptomatic AS patients with normal exercise response. These results thus suggest that ESE may provide additional prognostic information over that obtained from standard exercise testing and resting echocardiography.

Paradoxical low-flow, low-gradient severe aortic valve stenosis (AVS) may occur despite preserved left-ventricular (LV) ejection fraction in older females with marked LV concentric remodeling and small LV cavity size or in patients with coexisting severe mitral regurgitation. This report illustrates the case of a paradoxical low-flow, low-gradient severe AVS despite preserved LV function related to an ostium secundum atrial septal defect (ASD) in a patient presenting with congestive heart failure. Left-to-right shunt ASD that lowers forward LV stroke volume translating into lower transvalvular gradients is an underrecognized cause of paradoxical low-flow, low-gradient severe AVS. In addition, if not detected before open-heart surgery, ASD may result in cardiopulmonary bypass life-threatening complications.

Secondary mitral regurgitation (MR) has been extensively studied in heart failure due to reduced ejection fraction. In contrast, the occurrence and the pathogenesis of secondary MR are much less known in heart failure with preserved ejection fraction (HFpEF). The present review aimed at describing this common but ignored feature of HFpEF.

Patients presenting with mitral regurgitation and acute heart failure remain a challenge for the clinicians. Bedside echocardiography ascertains the functional or primary nature of mitral regurgitation, thereby allowing to focus therapy on the left ventricle and mitral valve apparatus in patients with functional mitral regurgitation and to hasten mitral valve repair or replacement when acute heart failure results from primary mitral regurgitation. This short article reviews the evaluation by bedside echocardiography to guide management of these patients.

Background: Patients with heart failure with preserved ejection fraction (HFpEF) may present with Pulmonary hypertension (PH) and functional mitral regurgitation (MR). Whether PH is linked to the presence of functional MR has not been investigated in HFpEF patients. Methods and results: Systolic pulmonary artery pressure (sPAP) and functional MR were assessed by 2-dimensional Doppler echocardiography in 70 ambulatory HFpEF patients and 70 hypertensive control subjects free of organic mitral valve lesions, significant valve disease, and comorbid conditions associated with PH. Whereas none of control subjects had more than trivial MR, 21 patients with HFpEF had functional MR (mean mitral effective regurgitant orifice, regurgitant volume, and regurgitant fraction 7 ± 3 mm,(2) 15 ± 8 mL, and 28 ± 14%, respectively). Pulmonary hypertension (sPAP >35 mm Hg) was significantly more prevalent in HFpEF patients with functional MR than in HFpEF patients without functional MR (62 vs 22%; P = .002). Functional MR remained an independent predictor of PH in HFpEF patients (P = .004) after adjustment on mitral E wave to e' mitral annulus velocity ratio (E/e'; P = .022) and left atrial volume index (P = .025). Systolic PAP and E/e' were greater in HFpEF patients than in control subjects (35 ± 9 vs 29 ± 8 mm Hg [P < .0001] and 13 ± 6 vs 11 ± 5 [P = .018], respectively). Systolic PAP remained greater in HFpEF patients than in control subjects after adjusting for E/e' (P = .002). Conclusions: Pulmonary hypertension appears to be linked to the presence of functional MR in HFpEF patients.

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.

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

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.