Typically, patients with mitral stenosis have normal or
reduced LV diastolic pressures, except for the rare occurrence
of coexisting myocardial disease. The same hemodynamic
findings are present in patients with other etiologies
of LV inflow obstruction, such as as LA tumors, cor triatriatum,
and congenital mitral valve stenosis.
The transmitral gradient is influenced by the severity of
stenosis, cardiac output, and the diastolic filling period. If
atrial fibrillation occurs, LA pressure increases to maintain
adequate LV filling. Although the severity of valvular
stenosis, patient symptoms, and secondary pulmonary
hypertension are the focus of clinical management, a semiquantitative
estimation of instantaneous LA pressure can be
provided in early and late diastole by Doppler variables. The
shorter the IVRT (auscultatory opening snap interval) and
the higher peak E-wave velocity (modified Bernoulli
equation; P ¼ 4V2), the higher the early diastolic LA
pressure. LA pressure is significantly elevated at enddiastole
if the mitral velocity remains .1.5 m/s at this
point. In addition, the IVRT/(TE 2 Te´) ratio correlates well
with mean PCWP and LA pressure (a ratio ,4.2 is accurate
in identifying patients with filling pressures .15 mm Hg).
However, the E/e´ ratio is not useful.69
Key Point. Mitral stenosis renders the assessment of LV
diastolic function more challenging, but IVRT, TE-e´, and
mitral inflow peak velocity at early and late diastole can
be of value in the semiquantitative prediction of mean LA
pressure.