Low-level exercise echocardiography fails to elicit left ventricular contractile reserve in patients with aortic stenosis, reduced ejection fraction, and low transvalvular gradient.
BACKGROUND
Low-level exercise echocardiography is useful to assess left ventricular (LV) contractile reserve after an acute myocardial infarction. Whether low-level exercise can elicit LV contractile reserve in patients with severe aortic stenosis, reduced LV systolic function and low transvalvular gradient are unknown. Accordingly, the value of low-level exercise to elicit contractile reserve was assessed in these patients using dobutamine administration as the gold standard method.


RESULTS
Seventeen patients with severely decreased aortic valve area (0.75 +/- 0.03 cm(2)), reduced LV ejection fraction (35 +/- 2%) and low mean transvalvular gradient (23 +/- 3 mmHg) underwent low-level exercise and dobutamine echocardiography. Ejection fraction increased by 23% (P < 0.001) with dobutamine and decreased by 8% (P = 0.2) with low-level exercise. Left ventricular outflow tract velocity time integral increased from 13 +/- 1 to 16.7 +/- 1 cm (P < 0.001) with dobutamine but did not change with low-level exercise (13 +/- 1 vs. 13.5 +/- 1, P = 0.5).


CONCLUSIONS
Low-level exercise fails to elicit LV contractile reserve in patients with severe aortic stenosis, reduced LV systolic function, and low transvalvular gradient.
Ennezat
Pierre V
PV
Cardiology Hospital, Lille, France. ennezat@yahoo.com
Toussaint
Juliette
J
Maréchaux
Sylvestre
S
Le Tourneau
Thierry
T
Aubert
Jean Marc
JM
Asseman
Philippe
P
LeJemtel
Thierry H
TH
Deklunder
Ghislaine
G
D000368:Aged; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000187:drug effects; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002316:Cardiotonic Agents / Q000008:administration & dosage; D004280:Dobutamine / Q000008:administration & dosage; D025401:Echocardiography, Stress; D005260:Female; D006801:Humans; D008297:Male; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*
D002316:Cardiotonic Agents; D004280:Dobutamine