Abnormal diastolic unopacified blood front: a useful marker of mitral stenosis.

The left ventriculograms of 113 patients, divided into seven groups, were reviewed for the detection of unopacified front (UOF) of blood entering the left ventricle (LV) during diastole. Normal UOF was detected in all the patients without left-sided valvular heart disease (regardless of the existence of coronary artery disease), constrictive pericarditis, aortic stenosis, and mitral regurgitation, although in the last group the UOF faded after several beats in 70% of cases. Only 5% of the patients with isolated mitral stenosis (MS) had an UOF, 75% had an abnormal UOF (< 60% of LV inflow tract), and 20% (with the greatest degree of MS) had only a dilution effect. A dilution effect was found in 62.5% of the patients with severe (> or = 3 degrees) aortic regurgitation (AR). An abnormal UOF is a sensitive and specific marker of significant MS. A dilution effect is indicative of either a significant MS or severe AR.