The acute onset of dyspnea
with a muffled S1and a brief early diastolic murmur at the base
should always raise the suspicion of acute aortic regurgitation
(AR).
The large regurgitant flow into a normal
sized left ventricle (LV) precipitously raises the LV end-diastolic
pressure (LVEDP) which in turn tends to close the mitral valve in
early diastole and produces the muffled S1.
The markedly elevated LVEDP decreases the
diastolic gradient across the aortic valve in late-diastole and
reduces the intensity and duration of the AR murmur.
Other relevant issues:
Of untreated patients with Type dissection
50% are dead within 48 hours and 90% at one month.
Death is usually due to rupture of the aorta
into the pericardial sac or pleural space or due to acute AR with
LV failure.
Classic findings of wide pulse pressure
and bounding pulse of chronic AR are usually absent in acute cases.
The patients BP was normal in the right
arm and 190/130 mm Hg in the left arm.
In the setting of early interstitial pulmonary
edema, the lungs may be clear.
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