A “biphasic” response of a segment or segments to dobutamine during a stress echocardiogram is interpreted to mean:
a. Ischemia in the territory supported by that artery
b. Infarction in the territory supported by that artery
c. Normal response to dobutamine
d. Ischemia and viability in the territory supported by that artery
e. Indeterminate result
Answer d:
The “biphasic” response to dobutamine during a stress echocardiogram refers to the improvement of function in an area of resting regional akinesis (essentially no wall motion at rest) at low dose dobutamine, followed by deterioration of function or ischemia in that same region at a higher rate pressure product, inferring that that area, if revascularized, should avoid an ischemic event in the future. A region of akinesis that remains akinetic infers infarction. A region of akinesis that improves at high dose infers recruitment of what functioning fibers remain, but not ischemia.
a. Ischemia in the territory supported by that artery
b. Infarction in the territory supported by that artery
c. Normal response to dobutamine
d. Ischemia and viability in the territory supported by that artery
e. Indeterminate result
Answer d:
The “biphasic” response to dobutamine during a stress echocardiogram refers to the improvement of function in an area of resting regional akinesis (essentially no wall motion at rest) at low dose dobutamine, followed by deterioration of function or ischemia in that same region at a higher rate pressure product, inferring that that area, if revascularized, should avoid an ischemic event in the future. A region of akinesis that remains akinetic infers infarction. A region of akinesis that improves at high dose infers recruitment of what functioning fibers remain, but not ischemia.
Labels
Radiology