The Journal of Thoracic and Cardiovascular Surgery, Vol 71, 450-457, Copyright © 1976 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Noninvasive diagnosis of complications of the mitral bioprosthesis
MS Horowitz, DJ Goodman, EW Hancock and RL Popp
The echophonocardiographic diagnoses of valvular and paravalvular
insufficiency, calcific stenosis, and thrombolic occlusion of the stent-
mounted aortic homograft or heterograft in the mitral position are
described. Paravalvular and valvular insufficiency were associated with
apical systolic murmurs which decreased in intensity after amyl nitrite
inhalation and with echocardiograms which showed initial diastolic slopes
of the stents in excess of the normal range (1.9 to 3.3 cm. per second). In
clinically improved and stable patients, amyl nitrite inhalation resulted
in increased intensity of the commonly heard systolic ejection type murmur
at the left sternal border and echocardiographic evidence of further
narrowing of the outflow tract measured between the interventricular septum
and the anterior portion of the stent. Calcific homograpft stenosis was
associated with a decreased diastolic stent slope (0.4 cm. per second) and
increased echo density from the tissue leaflets. Thrombus formation on the
sewing ring caused fatal inflow occlusion in 2 patients. The condition was
characterized by an echocardiogram showing decreased ratio of internal-
to-external stent diameter, 0.47 (normal range 0.56 to 0.74), decreased
diastolic stent slope, and decreased leaflet excursion.
