Introduction
Rheumatic heart disease (RHD) is endemic in developing countries, where
it remains the second most common cause of cardiovascular morbidity and
mortality after atherosclerotic cardiovascular disease Mitral valve is
the most commonly involved valve being afflicted in 60.2% patients,
with mitral stenosis (MS) being the most common valve lesion in chronic
RHD. MS causes obstruction to left ventricular (LV) diastolic filling,
leading to morphological and functional changes in left atrium (LA) as a
result of LA pressure overload. The elevated LA pressure is transmitted
back to pulmonary circulation resulting in exertional dyspnea and
ultimately leads to development of post-capillary pulmonary
hypertension. LA compliance is an important determinant of LA pressure
as different LA pressures are recorded in different subjects despite
similar mitral valve areas (MVA).4 Chronic LA pressure
overload leads to atrial muscle bundle disorganization and fibrosis
resulting in both atrial stiffness and atrial reservoir
dysfunction.5 The left atrial dysfunction may be
detected and quantified by deformation imaging i.e. speckle tracking
echocardiography (STE). STE is a reliable and effective tool for
evaluating LA function.
LA dysfunction has been reported in patients with rheumatic
MS.10 However most studies have either assessed global
LA strain, reservoir or conduit strain values with contractile strain
being reported only in mild to moderate MS.10,11 Only
very limited data is available regarding all three strain parameters in
patients with severe MS. In the present study
we assessed LA function
(reservoir, conduit strain and contractile strain) by two-dimensional
speckle tracking echocardiography and its correlation with clinical
symptoms and echocardiography parameters in patients with isolated
severe MS with pulmonary hypertension and healthy controls.