Monica Rosca

Clinical Outcome in Asymptomatic Severe Aortic Stenosis Insights From the New Proposed Aortic Stenosis Grading Classification

OBJECTIVES This study examined the clinical course of patients with asymptomatic severe aortic stenosis (AS) according to the new proposed aortic valve stenosis grading classification. BACKGROUND The management of patients with asymptomatic severe AS remains controversial. Moreover, under the same denomination of severe AS, several entities might be identified according to transvalvular flow rates and pressure gradients, resulting in 4 flow-gradient patterns. METHODS Transthoracic echocardiography and measurement of B-type natriuretic peptide level from venous blood sample were performed in 150 consecutive patients with asymptomatic severe AS and normal exercise test. Patients were classified in 4 groups, depending on left ventricular flow state (normal flow [NF] vs. low flow [LF]: 35 ml/m(2)) and pressure gradient levels (low gradient [LG] vs. high gradient [HG]: 40 mm Hg). RESULTS Patients with NF/LG had significantly lower B-type natriuretic peptide than those with LF/HG and LF/LG. The mean follow-up was 27 ± 12 months. At 2 years, cardiac event-free survival was 83 ± 6%, 44 ± 6%, 30 ± 12%, and 27 ± 13% in NF/LG, NF/HG, LF/HG, and LF/LG groups, respectively (p < 0.0001). On multivariable analysis, LF/LG (hazard ratio [HR]: 5.26, 95% confidence interval [CI]: 2.04 to 14.3, p = 0.045) and LF/HG (HR: 2.38, 95% CI: 1.02 to 5.55, p = 0.001) were identified as strong independent determinants of poor prognosis as compared with NF/HG. By limiting the multivariable analysis to patients with LF, LF/LG was an independent predictor of markedly reduced cardiac event-free survival when compared with LF/HG (HR: 5.4, 95% CI: 1.03 to 28.6, p = 0.046). CONCLUSIONS The use of the new proposed AS grading classification integrating valve area and flow-gradient patterns allows a better characterization of the clinical outcome of patients with asymptomatic severe AS.

Determinants and Prognostic Significance of Exercise Pulmonary Hypertension in Asymptomatic Severe Aortic Stenosis

Background— Recent studies emphasized the usefulness of exercise stress echocardiography in asymptomatic patients with aortic stenosis. Nevertheless, the additive value of exercise pulmonary hypertension (Ex-PHT) in such patients remains unexplored. We therefore aimed to identify the determinants and to test the impact on outcome of Ex-PHT in asymptomatic patients with severe aortic stenosis. Method and Results— Asymptomatic patients with severe aortic stenosis (n=105; aortic valve area <0.6 cm2/m2; age, 71±9 years; male, 59%) and preserved left ventricular systolic function (ejection fraction ≥55%) were prospectively submitted to exercise stress echocardiography. Resting PHT and Ex-PHT were defined as a systolic pulmonary arterial pressure >50 and >60 mm Hg, respectively. Ex-PHT was more frequent than resting PHT (55% versus 6%; P<0.0001). On multivariable logistic regression, the independent predictors of Ex-PHT were male sex (odds ratio, 4.3; P=0.002), resting systolic pulmonary arterial pressure (odds ratio, 1.16; P=0.002), exercise indexed left ventricular end-diastolic volume (odds ratio, 1.04; P=0.026), exercise e′-wave velocity (odds ratio, 1.35; P=0.047), and exercise-induced changes in indexed left atrial area (odds ratio, 1.36; P=0.006). Ex-PHT was associated with reduced cardiac event-free survival (at 3 years, 22±7% versus 55±9%; P=0.014). In a multivariable Cox proportional hazards model, Ex-PHT was identified as an independent predictor of cardiac events (hazard ratio, 1.8; 95% confidence interval, 1.0–3.3; P=0.047). When exercise-induced changes in mean aortic pressure gradient were added to the multivariable model, Ex-PHT remained independently associated with reduced cardiac event-free survival (hazard ratio, 2.0; 95% confidence interval, 1.1–3.6; P=0.025). Conclusions— In asymptomatic patients with severe aortic stenosis, the main determinants of Ex-PHT are male sex, resting systolic pulmonary arterial pressure, and exercise parameters of diastolic burden. Moreover, Ex-PHT is associated with a 2-fold increased risk of cardiac events. These results strongly support the use of exercise stress echocardiography in asymptomatic aortic stenosis.

Left atrial function: pathophysiology, echocardiographic assessment, and clinical applications

This article describes the pathophysiology of left atrial mechanical function and discusses both conventional and new echocardiographic parameters used to evaluate left atrial function. The evidence regarding the clinical usefulness of left atrial function assessment is also presented. Atrial function, in a close interdependence with left ventricular (LV) function, plays a key role in maintaining an optimal cardiac performance. The left atrium (LA) modulates LV filling through its reservoir, conduit, and booster pump function, whereas LV function influences LA function throughout the cardiac cycle. The LA can act to increase LA pressure (in significant atrial disease) and can react to increased LV filling pressure (in significant ventricular disease). LA remodelling is related to LV remodellingw1 and LA function has a central role in maintaining optimal cardiac output despite impaired LV relaxation and reduced LV compliance.1 Understanding how each component of LA function is influenced by LV performance, and how each LA phasic function contributes to maintain an optimal stroke volume in normal and diseased hearts, is important for interpreting data derived from quantification of LA function. During LV systole and isovolumic relaxation, the LA functions as a reservoir, receiving blood from the pulmonary veins and storing energy in the form of pressure. This atrial function is modulated by LV contraction, through the descent of the LV base during systole, by right ventricular systolic pressure transmitted through the pulmonary circulation, and by LA properties (ie, relaxation and chamber stiffness).w2 During early …

Left atrial dysfunction as a correlate of heart failure symptoms in hypertrophic cardiomyopathy.

BACKGROUND Hypertrophic cardiomyopathy (HCM) represents a generalized myopathic process affecting both ventricular and atrial myocardium. We aimed to assess left atrial (LA) function by two-dimensional speckle tracking echocardiography and its relation with left ventricular (LV) function and clinical status in patients with HCM. METHODS We prospectively enrolled 37 consecutive patients with HCM and 37 normal subjects with similar age and gender distribution. Longitudinal LV strain (ε) and LA ε and strain rate (Sr) parameters (systolic, early diastolic, and late diastolic during atrial contraction) were assessed. RESULTS Peak LAε and LA Sr parameters were significantly lower in patients compared with controls (P ≤ .001 for all). In patients, all LA function parameters correlated with LVε (P < .003 for all). Indexed LA volume, LA function parameters, and mitral regurgitation degree were the main correlates of New York Heart Association class; late diastolic strain rate during atrial contraction was the only independent predictor of symptomatic status. CONCLUSION In patients with HCM, LA function is significantly reduced and related to LV dysfunction. Moreover, LA booster pump function emerged as an independent correlate of heart failure symptoms in this setting.

Impact of aortic stenosis on longitudinal myocardial deformation during exercise

UNLABELLED In aortic stenosis (AS), left ventricular (LV) adaptation to exercise has poorly been examined. Changes in LV ejection fraction may lack accuracy in identifying the presence of intrinsic myocardial impairment. AIMS We sought to determine the impact of aortic stenosis (AS) on left ventricular (LV) longitudinal function at exercise in a series of asymptomatic patients with AS and preserved LV ejection fraction. METHODS AND RESULTS Long-axis function was assessed at rest and at exercise by using 2D speckle tracking of myocardial deformation in 207 AS patients (aortic valve area 0.87 ± 0.19 cm²) and 43 aged-matched control subjects. When compared with control subjects, patients with AS have reduced longitudinal myocardial function at rest (-20.2 ± 2.7 vs. -15.4 ± 4.0%) and at peak exercise (-25.0 ± 3.7 vs. -16.5 ± 4.9%) (P < 0.0001 for both). Exercise changes in global longitudinal strain were correlated with changes in LV ejection in controls but not in patients with AS. Changes in LV global longitudinal strain during test were lower in AS patients with an abnormal response to exercise (-0.5 ± 2.7 vs. -1.5 ± 2.8%, P = 0.001). In multivariate analysis, a lower global longitudinal strain at rest (P = 0.04), a higher increase in mean trans-valvular pressure gradient (P < 0.001) at exercise, and smaller exercise-induced changes in global longitudinal strain (P < 0.001) were associated with an abnormal exercise test. CONCLUSION In AS, subnormal LV function can be reliably identified by 2D strain imaging at rest and during a sub-maximal exercise. That sensitive measure of LV systolic function is depressed in AS and even more in patients having the most severe AS.

Left ventricular remodelling and torsional dynamics in dilated cardiomyopathy: reversed apical rotation as a marker of disease severity

Decreased left ventricular (LV) rotation and torsion and even reversed systolic apical rotation have been described in patients with dilated cardiomyopathy (DCM). We sought to test in patients with DCM whether reversed apical rotation with loss of LV torsion is related to the extent of LV remodelling and to the severity of LV dysfunction.

Left atrial function and remodelling in aortic stenosis

AIMS The present study sought to determine the relationship between left atrial (LA) volume (structural changes) and LA function as assessed by strain rate imaging in patients with aortic stenosis (AS). METHODS AND RESULTS The study consisted of a total of 64 consecutive patients with severe AS (<1 cm²) and 20 healthy control subjects. The phasic LA volumes and function (tissue Doppler-derived strain) were assessed in all patients. As compared with healthy controls, all strain-derived parameters of LA function were reduced in patients with AS. Conversely, only indexed LA passive volume (increased) (7.6 ± 3.8 vs. 10.5 ± 5.1 ml/m², P= 0.02) and LA active fraction (decreased) (43 ± 6.7 vs. 31 ± 13.3%, P< 0.001) (volume-based parameters) were significantly different between AS and controls. In AS, LA volume-derived function parameters were poorly correlated with LA strain parameters. In fact, by multivariable analysis, no LA phasic strain parameters emerged as independently associated with LA phasic volume parameters. CONCLUSIONS In AS, changes in LA function did not parallel changes in LA size. Furthermore, the increase in LA volume does not necessarily reflect the presence of intrinsic LA dysfunction.

Impact of aortic valve stenosis on left atrial phasic function.

The aim of this study was to determine the impact of aortic stenosis (AS) on the different components of left atrial (LA) function. The study consisted of a total of 52 consecutive patients with severe AS (aortic valve area < 1 cm(2)) and 20 normal subjects matched for gender, heart rate, body surface area, and baseline systolic blood pressure. Phasic LA longitudinal function was assessed using tissue Doppler imaging. LA peak systolic (reservoir function), early diastolic (conduit function), and late diastolic (active function) strain rates were measured. During late diastole, LA peak strain (active function) was also measured. Mitral annular systolic, early diastolic (Ea), and late diastolic (Aa) velocities were also measured. Compared with controls, all strain values were significantly reduced in patients with AS. By multivariate regression analysis, mitral E-wave deceleration time (p = 0.033) and E/Ea ratio (p = 0.02, R(2) = 0.43) emerged as independently associated with LA peak systolic strain rate. Ea was the sole determinant of LA early diastolic strain rate (p < 0.0001, R(2) = 0.42), whereas LA late diastolic strain rate was independently related to aortic valve area (p = 0.031) and Aa (p = 0.022, R(2) = 0.51). In conclusion, in patients with severe AS, the 3 components of LA function are reduced. LA reservoir dysfunction is related to left ventricular filling pressures, whereas LA conduit dysfunction depends on left ventricular relaxation. Active LA dysfunction is related to the severity of AS and late left ventricular diastolic function.

Hydroxymethylglutaryl coenzyme-a reductase inhibitors delay the progression of rheumatic aortic valve stenosis a long-term echocardiographic study.

OBJECTIVES This study sought to assess the effect of hydroxymethylglutaryl coenzyme-A reductase inhibitors (statins) on the progression of rheumatic aortic valve stenosis. BACKGROUND The possible role of statins in slowing the progression of degenerative aortic valve stenosis (AS) is still debated. No information about the role of statin treatment in patients with rheumatic AS is available yet. METHODS From our 1988 to 2008 echocardiographic database, we retrospectively identified all patients with rheumatic AS, with a baseline peak aortic velocity >or=1.5 m/s and at least 2 echocardiographic studies >or=2 years apart. Exclusion criteria were: severe aortic regurgitation, bicuspid aortic valve, and left ventricular ejection fraction <40%. RESULTS The study population consisted of 164 patients (30 treated with statins) followed up for 8.5 +/- 4.2 years. Peak aortic velocity at baseline was not different in patients treated with statins versus untreated patients (2.3 +/- 0.8 m/s vs. 2.3 +/- 0.7 m/s, p = 0.84). There were no significant differences in sex, age, or follow-up duration between the 2 groups. Progression of AS severity was slower in patients receiving statins compared with untreated patients (annual change of peak aortic velocity: 0.05 +/- 0.07 m/s/year vs. 0.12 +/- 0.11 m/s/year, p = 0.001). An annual rate of peak velocity progression >or=0.1 m/s was found in 10% of statin-treated patients and in 49% of untreated patients (p < 0.0001). CONCLUSIONS This is the first observation of a positive effect of statin treatment in reducing the progression of rheumatic AS. The underlying mechanisms remain to be clarified.

Echo-Tracking Assessment of Carotid Artery Stiffness in Patients with Aortic Valve Stenosis

Background: There is little information about mechanical properties of large arteries in patients (pts) with aortic stenosis (AS). Methods: Nineteen patients with AS (aortic valve area: 0.88 ± 0.29 cm2) and 24 control subjects without AS but with a similar distribution of risk factors were recruited. β index, pressure‐strain elastic modulus (Ep), arterial compliance (AC), augmentation index (AIx), and local pulse‐wave velocity (PWV) were obtained at the level of right common carotid artery (CCA) by a real time echo‐tracking system. Time to dominant peak of carotid diameter change waveform, corrected for heart rate (tDPc), and maximum rate of rise of carotid diameter (dD/dt) were measured. Systemic arterial compliance (SAC) was also calculated. Parameters of AS severity (mean gradient, valve area, stroke work loss [SWL]) were determined. Results: tDPc was higher in patients with AS than in controls (7.9 ± 0.6 vs. 6.6 ± 0.7, P < 0.0001) while dD/dt was lower (5.3 ± 3.6 mm/s vs. 7.8 ± 2.8 mm/s, P = 0.01). AIx was significantly higher in AS group (32.5 ± 13.6% vs. 20.6 ± 12.2%, P = 0.005) and had a linear correlation both with tDPc (r = 0.63, P < 0.0001) and with dD/dt (r =−0.38, P = 0.01). There was a significant correlation between carotid AC and SAC (r = 0.49, P = 0.03), but only carotid AC was related to SWL (r = 0.51, P = 0.02), while SAC was not (P = 0.26).Conclusions: AIx was the only parameter of arterial rigidity found to be higher in patients with AS than in controls. Carotid AC showed a significant correlation with SAC and it seemed to be more closely related to AS severity than to SAC.