Prognostic Effect of Long-Axis Left Ventricular Dysfunction and B-Type Natriuretic Peptide Levels in Asymptomatic Aortic Stenosis

Abstract

In aortic stenosis (AS), the increased afterload results in progressive structural and functional changes that precede the development of symptoms. We hypothesized that the detection of abnormalities in left ventricular long-axis function could identify patients with asymptomatic AS at increased risk of events. We prospectively examined the outcome of 126 patients with asymptomatic AS who underwent a comprehensive echocardiographic examination, including tissue Doppler imaging. B-type natriuretic peptide ( Aortic valve stenosis (AS) is the most common valvular disease and has become the most common cardiovascular disease, after coronary artery disease and hypertension, in developed countries. 1 AS is characterized by a long asymptomatic phase, lasting several decades, during which outflow obstruction progressively develops. 2 Aortic valve replacement is the sole effective therapy for symptomatic patients. In contrast, the management of asymptomatic AS remains controversial. 3,4 In these patients, the chronically increased afterload results in progressive left ventricular (LV) myocardial hypertrophy and interstitial fibrosis, diastolic dysfunction, elevated left atrial pressures, dilation of the left atrium, and, eventually, intrinsic myocardial dysfunction. 5 These structural and functional changes precede symptom development, predict changes in clinical status, and trigger B-type natriuretic peptide (BNP) release. 6,7 In AS, the BNP level correlates with the valve area, diastolic function, functional status, and symptomatic deterioration and might improve risk stratification. 8 -11 Tissue Doppler measurement of mitral annular velocities is a sensitive method for the detection of early abnormalities in LV longaxis function and improves the assessment of LV diastolic function. 12 In asymptomatic AS, the incremental prognostic value of tissue Doppler imaging and BNP measurement compared with validated parameters has never been investigated. The present study was undertaken to prospectively assess the comparative usefulness in predicting the clinical outcomes of long-axis function and BNP level in a series of patients with asymptomatic severe AS. MethodsAsymptomatic patients with severe AS were prospectively screened from our echocardiographic laboratory for inclusion in the present study. All the patients met the following criteria: (1) moderate to severe AS, as defined by an aortic valve area of Յ1.2 cm 2 ; (2) no symptoms according to a careful history taken by the referring physician; (3) normal LV ejection fraction (Ն55%), as calculated by 2-dimensional echocardiography; (4) no more than mild associated cardiac valve lesions; (5) sinus rhythm; and (6) serum creatinine Ͻ16 mg/L. A total of 126 patients met these criteria. The relevant institutional review boards approved the protocol, and all patients gave written informed consent.A comprehensive Doppler echocardiographic study, including M-mode, 2-dimensional echocardiography, color Doppler, and pulsed-wave and continuous-wave Doppler measurements was perform...

Brain natriuretic peptide release in patients with aortic stenosis: Resting and exercise echocardiographic determinants

“…However, at a later stage, LV hypertrophy may be no longer sufficient to compensate the afterload and increase in LV wall stress and filling pressure may occur resulting in symptoms and poor outcome. The E/e′ ratio is recognized as a noninvasive measurement of LV filling pressure in patients with AS [5,6] and the BNP activation is known to be a good surrogate marker of the occurrence of symptoms [6,7]. Consistently, our results have shown that the main determinant of BNP level is the estimated LV filing pressure using E/e′ ratio.…”

“…However, the mechanism of NK cell dysfunction in CAD remains unclear. The core of toxic granules in NK cells is surrounded by a lipid bilayer that contains Fas ligand and LAMPs [6]. As degranulation occurs, secretory lysosomes are released, and LAMP-1 (known as CD107a) is transported to the cellular surface.…”

Impact of Serial B-Type Natriuretic Peptide Changes for Predicting Outcome in Asymptomatic Patients With Aortic Stenosis

“…20 In symptomatic or asymptomatic severe AS with structural impairment such as diastolic dysfunction, LA dilatation, LV hypertrophy, and fibrosis, elevated single BNP level measurement is a marker of already elevated LV filling pressures predicting poor short-term outcome. 9,10 However, in asymptomatic moderate-to-severe AS without significant structural changes, the baseline BNP level is potentially more dependent on the overall patients' picture (age, gender) rather than on the degree and consequences of AS. 18 This can explain the discrepant results observed in the present cohort and previous published data, even by our group.…”

“…8 Previous studies already showed that single measurement of a BNP level correlates with AS severity and their harmful consequences on diastolic function, functional status, and symptomatic deterioration. [9][10][11] Moreover, recent European Society of Cardiology guidelines have suggested BNP level measurement for risk stratification in asymptomatic AS. 2 Some authors have evaluated serial BNP measurements in patients with valvular heart disease demonstrating a better prediction of outcome compared with single measurements.…”

“…Different cutoff values, ranging from 61 to 130 pg/mL, have been related to the occurrence of symptoms, need for aortic valve replacement, and cardiac-related death. [9][10][11] To note, those cutoff values were not adjusted to counteract the interindividual variation of BNP levels related to age and gender. To address this issue, Clavel et al have shown that BNP normalized to age and sex was also highly predictive of outcomes in a large cohort.…”