Haematologic determinants of left atrial spontaneous echo contrast in mitral stenosis

To determine if a relationship exists in mitral stenosis, in patients with either sinus rhythm or atrial fibrillation, between left atrial spontaneous echo contrast and the haematologic indices haematocrit, red cell concentration, mean corpuscular volume, platelet count and volume.

Left atrial spontaneous echo contrast severity was graded on a scale of 0-4 in 163 patients with symptomatic mitral stenosis (84 patients in sinus rhythm, 79 patients in atrial fibrillation) undergoing transesophageal echocardiography, cardiac catheterization and full blood examination as part of assessment prior to balloon mitral valvuloplasty.

In sinus rhythm, spontaneous echo contrast grade was negatively correlated with cardiac index (r=-0.33), mitral valve area (r=-0.25) and mitral regurgitation grade (r=-0.22) and positively correlated with haematocrit (r=0.24) and red cell concentration (r=0.25). Spontaneous echo contrast grade was not correlated with left atrial diameter or mean corpuscular volume. In atrial fibrillation, spontaneous echo contrast grade was also negatively correlated with mitral valve area (r=-0.25) and mitral regurgitation (r=-0.36) but was positively correlated with left atrial diameter (r=0.34) and was not correlated with cardiac index, haematocrit or red cell concentration. There was no correlation between spontaneous echo contrast grade and platelet variables in either group.

Natural variation in red cell concentration in patients with symptomatic mitral stenosis was an independent predictor of the severity of left atrial spontaneous echo contrast in sinus rhythm, but no relationship between red cell concentration and spontaneous echo contrast grade was evident in atrial fibrillation.