Functional assessment of ALCAPA syndrome by dobutamine stress thallium-201 SPECT and echocardiography.

Exercise 201TI SPECT has been used as a useful method for the assessment of patients with anomalous left coronary artery communicating to the pulmonary artery (ALCAPA syndrome). In this study, we described an adult patient with this anomaly who was evaluated by dobutamine stress testing in conjunction with simultaneous 201Tl SPECT and echocardiography before and after surgery. A large perfusion defect in the anterior wall, septum and apex was detected on the preoperative stress scan with partial reversibility on reinjection scan.

Evaluation by quantitative 99m-technetium MIBI SPECT and echocardiography of myocardial perfusion and wall motion abnormalities in patients with dobutamine-induced ST-segment elevation.

ST-segment elevation during exercise testing has been attributed to myocardial ischemia and wall motion abnormalities (WMA). However, the functional significance of ST-segment elevation during dobutamine stress testing (DST) has not been evaluated in patients referred for diagnostic evaluation of myocardial ischemia. DST (up to 40 micrograms/kg/min) with simultaneous echocardiography and technetium-99m sestamibi single-photon emission computed tomography (SPECT) was performed in 229 consecutive patients with suspected myocardial ischemia who were unable to perform an adequate exercise test; 127 (55%) had a previous acute myocardial infarction (AMI).

Potential and limitations of Tc-99m sestamibi scintigraphy for the diagnosis of myocardial viability.

Sestamibi is a Tc labeled radiotracer particularly suitable for myocardial perfusion studies, providing similar information as thallium scintigraphy for the diagnosis of coronary artery disease. In comparison with thallium, sestamibi has the advantage of improved imaging properties due to its higher gamma emission. This is particularly relevant when SPECT imaging is considered.