Low-output, low-gradient aortic stenosis in patients with depressed left ventricular systolic function: the clinical utility of the dobutamine challenge in the catheterization laboratory.
BACKGROUND
Although aortic valve replacement can be performed at an acceptable risk level in selected patients with left ventricular systolic dysfunction and low-output, low-gradient aortic stenosis, not all patients presenting with these hemodynamics will benefit from the operation. Some patients may have only mild aortic stenosis, despite a small calculated valve area. We report on the clinical utility of diagnostic dobutamine stimulation during cardiac catheterization in these diagnostically challenging patients.


RESULTS
Thirty-two patients with low-output, low-gradient aortic stenosis and an ejection fraction <40% had dobutamine infusion in the catheterization laboratory. On the basis of the results of the dobutamine test, 21 patients underwent aortic valve replacement. All patients with a final aortic valve area < or =1.2 cm2 at peak dobutamine infusion and a mean gradient of >30 mm Hg were found to have severe calcific aortic stenosis at operation. In the 15 patients in whom contractile reserve was identified during dobutamine challenge (increase in stroke volume >20%), 1 patient died perioperatively (7% mortality) and 12 patients were alive in New York Heart Association class I or II status at follow-up.


CONCLUSIONS
In patients with left ventricular systolic dysfunction and aortic stenosis with a low output and a low mean gradient, dobutamine challenge may aid in selecting those who would benefit from an aortic valve operation.
Nishimura
Rick A
RA
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, Minn 55905, USA.
Grantham
J Aaron
JA
Connolly
Heidi M
HM
Schaff
Hartzell V
HV
Higano
Stuart T
ST
Holmes
David R
DR
D000318:Adrenergic beta-Agonists; D000368:Aged; D001024:Aortic Valve Stenosis / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D006328:Cardiac Catheterization; D002316:Cardiotonic Agents; D004280:Dobutamine; D004305:Dose-Response Relationship, Drug; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D018579:Patient Selection; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013318:Stroke Volume / Q000187:drug effects; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis*
D000318:Adrenergic beta-Agonists; D002316:Cardiotonic Agents; D004280:Dobutamine