**6. Strain imaging—prognostic value in aortic stenosis**

LV strain analysis has been demonstrated to provide prognostic information in patients with aortic stenosis:


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*Clinical Applications of Strain Imaging in Aortic Valve Disease*

timing of aortic valve replacement [2].

• LV GLS is independently associated with all-cause mortality in AS patients. It can further risk stratify severe AS patients and may influence the optimal

• GLS is an independent predictor of all-cause mortality in severe AS, irrespective of their type of treatment. GLS <9.7% indicates a significantly higher 1 and 5-year mortality in non-AVR patients. Therefore, GLS should be regularly assessed for enhanced risk stratification and clinical decision-making [17].

• In normal LVEF patients with significant aortic stenosis, brain natriuretic peptide (BNP) and LV-GLS provide incremental prognostic information over established predictors, suggesting that both play a synergistic role in defining

• A drop in LVGLS in bicuspid aortic valve (BAV) with preserved LVEF is not infrequent and was independently associated with increased risk of events (mainly aortic valve replacement events), as found by Kong et al. [19] in 513 patients (68% men; mean age 44 ± 18 years) with BAV and preserved LVEF (>50%).

**7. Strain imaging in combined aortic stenosis and coronary artery** 

predominant in the apical and mid ventricular segments [20].

**8. Strain imaging sublayers in aortic stenosis**

in patients with AS [22].

Subclinical coronary artery disease is common in moderate and severe aortic stenosis, and should be suspected when regional longitudinal dysfunction is

Sublayer strain analysis may add additional information in the characterization of LV function in patients with aortic stenosis. The following studies address this

• In severe AS, longitudinal strain impairment affects all three myocardial layers but is more noticeable in the endocardial layer. This becomes more manifest in

• Bilayer strain ratio (subendocardial and subepicardial) can reliably differentiate patients with varying degrees of AS severity and is a sensitive marker of LV function. These findings suggest that the evaluation of subendocardial and subepicardial radial strain might be a novel method for assessing LV mechanics

• Medically treated patients with AS have worsening of GLS despite preserved LVEF, first appearing in the subendocardial layer. Global circumferential strain (GCS) becomes progressively impaired in moderate and severe AS. Improvement in LV strain after AVR is seen earlier with GLS than with GCS [23].

• There is differential impairment in LV systolic strain in all three cardiac axes in patients with AS. Left ventricular longitudinal strain impairment is proportional to AS severity. Subendocardial longitudinal strain correlates better with

the advanced phases of the disease when symptoms appear [21].

*DOI: http://dx.doi.org/10.5772/intechopen.93341*

outcomes [18].

**disease**

issue:

*Clinical Applications of Strain Imaging in Aortic Valve Disease DOI: http://dx.doi.org/10.5772/intechopen.93341*

*Advances in Complex Valvular Disease*

mended its clinical use in patients [9].

**5. Strain imaging and aortic stenosis severity**

changes in LV function in AS patients [12].

evaluation of LV function and prognosis [16].

patients with aortic stenosis:

replacement [14].

less) [13].

**6. Strain imaging—prognostic value in aortic stenosis**

tion indices has been demonstrated in the following studies:

Echocardiography (ASE) on cardiac chamber quantification acknowledged the incremental value of LV GLS over traditional LVEF measurements, and recom-

• Conventional measures of LVEF can be preserved until end-stage disease due to the compensatory development of concentric hypertrophy, and thus lacks accuracy in identifying subtle changes in myocardial contractility [2].

• Subclinical myocardial dysfunction with impaired LV GLS is frequently seen in patients with severe AS with preserved LVEF and no symptoms. Left ventricular global longitudinal strain deteriorates over time and impaired LV GLS at baseline is associated with an increased risk for progression to the symptomatic

A relationship between aortic stenosis severity and alterations in LV deforma-

• Strain and strain rate parameters relate to LV function and aortic stenosis

AVR before LV mass and LV function show improvement [11].

severity. Further, they appear to be superior to tissue velocity and conventional echocardiography in detecting subtle changes in myocardial function after

• Despite unchanged LVEF, GLS gradually decreased as severity of AS increases. GLS measured by 2D-speckle tracking imaging might be useful to assess subtle

LV strain analysis has been demonstrated to provide prognostic information in

• A recent met analysis, including 1067 asymptomatic patients, with AS and preserved LVEF, showed that LVGLS is strongly associated with mortality, with >2.5-fold increase in risk of death in patients with impaired LVGLS (−14.7% or

• Kusunose et al. [15] demonstrated on 395 patients that Longitudinal strain (LS) is independently associated with death in patients with AS and preserved LVEF, in addition they made the point that the flow/gradient pattern should also be considered as an important parameter. In the management of AS patients the use apical 4 chamber LS should be considered a new parameter of

• GLS detects subclinical dysfunction and has incremental prognostic value over traditional risk markers including hemodynamic severity, symptom class, and LVEF in patients with AS. Incorporation of GLS into risk models can improve the identification of the optimal timing for AV

stage and the need for aortic valve surgery or intervention [10].

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