Prognostic Impact of Myocardial Longitudinal Strain in Asymptomatic Aortic Stenosis: a Meta-Analysis

Study Overview
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Brief Summary
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In patients with asymptomatic aortic stenosis (AS), the prognostic value of reduced left ventricular (LV) ejection fraction is well known. Consequently, there is class I indication for surgery in these patients when LV ejection fraction <50%. However, there is growing evidences suggesting that subclinical LV dysfunction, and more particularly longitudinal myocardial dysfunction, may be a powerful early predictor of outcome, even when LV ejection is still preserved. In asymptomatic AS patients with LV ejection fraction >50%, a reduced LV global longitudinal strain, as assessed using speckle tracking imaging with transthoracic echocardiography, may be an accurate marker to identify early subclinical LV dysfunction and thus, to improve the risk stratification, the management and the timing of surgery. Several mono-centric observational small studies recently reported results emphasizing the role of LV global longitudinal strain in AS patients. Therefore, a meta-analysis may be conducted and may provide meaningful data. The investigators hypothesized that LV global longitudinal strain is a determinant of outcome in asymptomatic patients with AS and preserved LV ejection fraction.

Official Title
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Prognostic Impact of Myocardial Longitudinal Strain in Asymptomatic Aortic Stenosis: a Meta-Analysis

Conditions
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Aortic Valve Stenosis, Asymptomatic Conditions, Left Ventricular Function

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: studies selected in PubMed, Embase, Ovid, and Google Scholar, published between 2005 and 2015 without language restriction according to the following criteria: aortic stenosis AND longitudinal strain Exclusion Criteria: Studies reporting global longitudinal strain derived from VVI and not speckle tracking analysis. Studies with cohort of patients with aortic valve replacement indication

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Preserved LV GLS<br>Patients will be compared according to the level of LV global longitudinal strain (GLS) as derived from transthoracic echocardiography and speckle tracking analysis. Two groups will be compared regarding outcome: preserved LV GLS vs. reduced LV GLS. The definition use for reduced LV GLS will be >-16%. An optimal threshold would also be calculated and derived from the pooled data. | |
| Reduced LV GLS<br>The definition use for reduced LV GLS will be >-16%. An optimal threshold would also be calculated and derived from the pooled data. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Combined outcome of death and cardiovascular-related hospitalization (including aortic valve replacement) |  | up to 10 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Combined outcome of death and cardiovascular-related hospitalization (without aortic valve replacement) |  | up to 10 years |