Left Chamber Function in Mitral Regurgitation and Predicting Outcome After Replacement and Targeting for Early Surgery

Left Chamber Function in Mitral Regurgitation and Predicting Outcome After Replacement and Targeting for Early Surgery

Assessment of Subclinical Left Atrial and Left Ventricular Dysfunction by Speckle Tracking Echocardiography in Severe Asymptomatic Rheumatic Mitral Regurgitation and Its Role in Predicting Outcome After Valve Replacement Compared to Guideline Parameters

The study aims to analyze the role of left ventricular and left atrial functional parameters by speckle tracking echocardiography in predicting outcome after mitral valve replacement and targeting for early intervention compared to guideline parameters.

Without surgical treatment, the 10-year morbidity and mortality for patients with severe mitral regurgitation can be as high as 90%. In contrast, with successful surgical correction of mitral regurgitation before the appearance of symptoms, patients may have life expectancies similar to that of the general population. According to European recommendations, mitral valve replacement must be proposed to symptomatic patients and to patients with significant left ventricular remodeling as a consequence of the severity of mitral regurgitation. A significant decline in left ventricular function is defined, in these recommendations, echocardiographically as an left ventricular ejection fraction < 60% or an left ventricular end-systolic diameter > 45 mm. Preoperative left ventricular systolic function and left ventricular end systolic diameter are important postoperative prognostic factors. The early detection of left ventricular systolic dysfunction remains a challenge. Mitral regurgitation causes low left ventricular afterload, and the ejection fraction thus remains normal or supernormal until the disease reaches an advanced stage. Some authors have suggested the additive value of deformation indices as more sensitive than the ejection fraction to detect subclinical left ventricular systolic dysfunction Speckle tracking echocardiography has been well validated as a quantitative assessment tool for left ventricular function, and more recently this technique has been described for assessment of regional and global left atrial function

One group will be referred for surgery according according to indications for mitral valve replacement in European guidelines for valvular heart diseases published in 2017 and will have speckle tracking echocardiography before surgery and 6 months later for comparison.

The other group will include patients with severe asymptomatic mitral regurgitation who have left atrial or left ventricular dysfunction according to speckle tracking echocardiography and will be referred to surgery, then speckle tracking echo will be performed 6 months later.

Replacing the diseased mitral valve in cases with severe mitral regurgitation with a prosthetic valve.

We will perform Speckle tracking echocardiography in order to identify patients with early subclinical left ventricular or left atrial dysfunction and refer them to surgery, Then after surgery, speckle tracking echocardiography will be performed for all patients to assess improvement of left atrial (conduit, reservoir and booster contractile functions) and left ventricular (global longitudinal strain) function

Recovery of left atrial functions (conduit, reservoir and booster contractile functions) and left ventricular function (global longitudinal strain) by speckle tracking echocardiography after mitral valve replacement

Speckle tracking echocardiography will be performed 6 months after surgery to assess recovery of left atrial function by assessment of conduit, reservoir and booster contractile functions and left ventricular function by assessment of global longitudinal strain after mitral valve replacement

Quantifying patients with CVD events, admission for HF, ischemic cardiovascular events, cardiac death, or MACE within 6 months after surgery

Inclusion Criteria: Patients with rheumatic severe mitral regurgitation who will have mitral valve replacement in Assiut University Heart Hospital Exclusion Criteria: Degenerative mitral regurgitation, ischemic mitral regurgitation, severe rheumatic mitral regurgitation with atrial fibrillation or impaired left ventricular ejection fraction, associated mitral stenosis, or significant aortic regurgitation and ischemic heart disease.

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